ffhhhhhhhfgd

[textilegfg]

CHAIN MERCERIZING RANGE

In this machine the mercerizing lye causes fabric shrinkage, it is necessary to arrange the machine compliments in such a manner that the finished fabric satisfies the dimensional requirements in all respects.

a. Fabric entrance section: The fabric is taken off from its plighted condition through a set of automatic cloth guiders, guide rollers and tension bars.

b. Impregnation section: In the case of the chain type mercerizing machines, impregnation with the mercerizing lye is carried out in suitably dimensioned padding mangles.  The mercerizing lye having an optimum concentration of caustic soda is continuously fed to the trough of the padding mangle. The Single Web of fabric gets a dip in the lye and is then passed through the padding mangle, where the excess lye is squeezed out from the impregnated cloth. Small machines have one padder whenever more mercerizing production is required, but the passage through one padder is not sufficient to make up the lye action time. A second impregnation is, therefore introduced in the system.  Usually, two lye pads give the required production, but, first still higher production speeds, a third impregnation padder is necessary.  It is necessary to decide on the expected production before the installation of the mercerising range.

c. Width stretching and stabilizing section: The last in with due to shrink the by light action is to be recovered by stretching the impregnated cloth in at the stenter the length of the stenter difference on the production needed and is to be decided upon beforehand. A weak lye is sprayed on the fabric, while it is being stretched in the stenter frame.  The letter was from of the cloth in the stenter may be sprayed with a still weaker lye.

d. Steam recuperation zone: After squeezing the fabric at the end of the stenter through the squeezing mangle, the fabric is introduced into the lye recuperation section, where steam heated water, near boil, in the recuperation washing compartment with top and bottom rollers, recovers the major quantity of lye.

e. The washing section: The remaining portion of the lye is washed out of the cloth in the washing section having the requisite number of washing compartments.

Read About: Fabric Shrinkage http://textilecentre.blogspot.in/2016/09/types-of-shrinkage-in-fabric-fabric.html 

[textilegfg]

New Textile Finish with Antiviral and Antibacterial Effect

As part of an AiF research project, scientists from the Hohenstein Institute in Boennigheim are said to have for the first time developed a textile finish with both an antiviral and an antibacterial function. The  technology has been developed to be used for products in nurseries, child day care centres and hospitals to interrupt chains of infection.

Respiratory problems

Most infection-induced respiratory problems are caused by viruses, the researchers say. For example, the respiratory syncytial virus, a pathogen belonging to the family of paramyxoviruses, can cause infections of the upper respiratory tract in the form of colds, coughs, acute bronchitis or even pneumonia, particularly in small children.

To avoid droplet and smear infections as far as possible, hygienic hands, textiles and surfaces are of paramount importance, the Institute reports.

Risk of infection

Textiles can play a part in spreading pathogens. Viruses do not have their own metabolism and can therefore only survive for a limited time outside a host, and unlike bacteria, do not multiply there.

However, studies have shown that textiles that are in regular contact with hands can contribute to the spread of viruses. The test design included cleaning cloths in which, for the first time, antiviral and antibacterial effectiveness were combined with each other in one functional textile finishing.

“Over the long term, we are interested in finding out whether the risk of infection, that is to say the spread of germs from person to person, can be reduced by using biofunctional textiles in the future,” explained Prof Höfer, Head of the Hygiene, Environment and Medicine Department.

Antiviral finish

Various organic and inorganic colloidal or nanoparticle copper compounds and copper complexes were first applied in a sol-gel process. The effectiveness of the textile microfibre substrate was optimised using various application techniques such as foulard or spray methods.

A second alternative antiviral finish of microfibre cloths was achieved by finishing with copper pigments in a high-temperature exhaust process. In a similar way to dyeing with dispersion dyes, the dispersed copper pigments were incorporated in the fibres in a slightly acid environment. In a second step, fixing was carried out using a polymer binding agent in a cold padding process to protect the copper particles against mechanical abrasion.

Reducing virus concentration

The effectiveness tests were carried out on different surfaces, such as glass, stainless steel or wood, which were contaminated with viruses and wiped with the finished cleaning cloths. The bacterial virus MS2, a non-pathogenic surrogate virus, which is comparable to clinically relevant viruses such as novovirus, poliovirus, hepatitis A or enteroviruses, was used as the test virus.

The finished microfibre cloths absorbed 91% of the applied viruses, the Institute reports. At the same time, the virus concentration in the cloth was reduced by approximately 90 %.

In future, this new functionalisation could be of interest in the domestic environment, in hospitals, old people's homes, care homes and in communal facilities (e.g. canteens) and in protective clothing for the fire brigade, emergency services and military.F

www.hohenstein.de

[textilegfg]

Pressure Relieving cushion using Knitted Spacer Fabric

Technical warp knits specialist Baltex has launched Airospring,  a range of lightweight and breathable pressure relieving cushions made from high-tech 3D knitted spacer fabrics. The product is said to be the  result of many years of research by Quality of Life - QOL Design with the University of Bolton and Baltex Technical Textiles in the UK.

Using the latest three dimensional fabric technology new products have been developed to push the boundaries of comfort for cushions, Baltex reports.

Partnership

The University of Bolton is a leading institution in the development of technical textiles and medical textiles and with Bryan McArdle of Quality of Life and Baltex, it has  been working closely on this project for the past four years.

Baltex is a leading producer of 3 dimensional spacer fabrics and has been working closely with the University for the past ten years on a range of projects. With a wide range of equipment and knowhow Baltex is an innovative knitter and won the Innovation prize for Technical Textiles at the centenary world conference of the Textile Institute in Manchester in 2010.

Baltex uses CAD/CAM technology to develop the latest high performance fabrics that lie at the heart of Airospring and support has been provided by Medilink the healthcare I-Net based in the East Midlands, UK.

Comfortable and stimulating

The cushions are said to distribute weight and allow maximum airflow, which provides benefits to the skin and retains a healthy skin tone and can help blood flow generally for people sitting in one position for long periods of time.

Airospring cushions specifically target wheelchair users, people sitting in front of the computer all day long  and taxi drivers. They can also be used for concerts, outdoors or just those uncomfortable seats we have to endure from time to time.

Designed with the focus on health and comfort, the range is said to be non-allergenic and provide contamination resistance and odour control. New products are also under development and will be brought to market in the next 12 months.

AS 100 and AS 200

Airospring AS 100 and AS 200 cushions  are said to distribute pressure evenly, dissipate heat and help skin tone through hydration.

These are suitable for anyone who sits in the same position for long periods of time. Some of their characteristics include:

At 520gms weight it is approximately half the weight of many cushions on the market

Airospring is machine washable at 40C

It is totally breathable

The cushion promotes the movement of Air as you move so keeping you cool and comfortable

Pressure mapped, Airospring provides uniform support from all parts of the cushion

Conforms to BS EN ISO 1021 parts 1 & 2

[textilegfg]

Protective Clothing Standards

Protective clothing for industry has numerous standards. This listing includes those standards applicable to chemical protective clothing and hot work, protection from cuts, and molten metal as well as other types of hazards. They provide guidance for selection, use, proper care, and maintenance. There are so many standards for protective clothing, they can't all be listed here. Specialized standards for protective clothing in agriculture, violent situations, medical use, and standards for protective clothing manufacturers are not listed here.

Use the search by document number or keyword to find other standards particular to your needs. DIN, ON, BSI and others may have standards similar to the ones shown here that may apply to your situation.

ASTM F1001-99a (2006)

Standard Guide for Selection of Chemicals to Evaluate Protective Clothing Materials

The purpose of this guide is to provide a recommended list of both liquid and gaseous chemicals for evaluating protective clothing materials in testing programs

ASTM F1002-06

Standard Performance Specification for Protective Clothing for Use by Workers Exposed to Specific Molten Substances and Related Thermal Hazards

This performance specification covers textile materials to be used for protective clothing. Materials used for both primary protection and for secondary protection are covered. Protective properties relate to contact with molten substances and hot surfaces, and exposure to open flame and radiant heat. This performance specification covers clothing design characteristics that relate to the unique protective requirements of working with molten substances. This performance specification describes the properties of specific textile materials in their fabric or garment composite form as tested by laboratory methods and is not intended to be used to appraise the thermal hazard or fire risk under actual conditions.

ASTM F1296-08

Standard Guide for Evaluating Chemical Protective Clothing This guide is intended to aid in the application of standards for the development, specification, and selection of chemical protective clothing with the ultimate goal of maintaining the safety and health of workers who come into contact with hazardous chemicals. This guide provides a short description of each referenced standard and then makes specific recommendations for the use of these standards. The referenced standards are organized under the following headings: Material Chemical Resistance, Material Physical Properties, Seam and Closure Performance, and Overall Clothing Performance.

ASTM F1461-07

Standard Practice for Chemical Protective Clothing Program This practice is intended to promote the proper selection, use, maintenance, and understanding of the limitations of chemical protective clothing (CPC) by users, employers, employees, and other persons involved in programs requiring CPC, thereby limiting potentially harmful and unnecessary skin exposures.

ASTM F1731-96(2008)

Standard Practice for Body Measurements and Sizing of Fire and Rescue Services Uniforms and Other Thermal Hazard Protective Clothing.

This practice is intended to assist in size selection of work uniforms for fire and rescue services personnel and workers who may be exposed to thermal hazards. Work uniform ensembles consist of a shirt and trouser apparel combination. This practice is applicable to uniforms for both male and female personnel.This practice provides a standard means for measuring human body dimensions for the selection and ordering shirts and trousers. This practice provides a means for evaluating the fit of selected uniform sizes. This practice provides a standard list of textile and apparel terminology specific to the clothing industry which is used in determining size and fit of garments. This vocabulary will be useful in communications between buyers and sellers.

ASTM F2061-08

Standard Practice for Chemical Protective Clothing: Wearing, Care, and Maintenance Instructions.

This practice describes the recommended minimum information to be conveyed by the sellers to end users for the wearing, care, and maintenance of chemical protective clothing. This practice does not cover specific instructions for when to use protective clothing or design requirements.This practice does not apply to protective clothing that is solely for protection against flame and thermal hazards.

BS EN ISO 20349:2010

Personal protective equipment. Footwear protecting and thermal risks and molten splashes as found in foundries and welding. Requirements and test method (British Standard).

ISO 20349:2010 specifies requirements and test methods for footwear protecting users against thermal risks and molten iron or aluminium metal splashes such as those encountered in foundries, welding and allied process. Footwear complying with this International Standard also offers other protection as defined in ISO 20345.

BS 7184:2001

Selection, use and maintenance of chemical protective clothing. Guidance

JIS T 8031:2010

Clothing for protection against liquid chemicals -- Determination of the resistance of protective clothing materials to penetration by liquids under pressure (Foreign Standard)

JIS T 8061:2010

Clothing for protection against contact with blood and body fluids -- Determination of resistance of protective clothing materials to penetration by blood-borne pathogens -- Test method using Phi-X174 bacteriophage (Foreign Standard)

JIS T 8124-1:2010

Protective clothing for use against solid particulates -- Part 1: Performance requirements for chemical protective clothing providing protection to the full body against airborne solid particulates (type 5 clothing) (Foreign Standard)

ANSI/ISEA 103-2010 erratum sheet

Eratum sheet for Classification and Performance Requirements for Chemical Protective Clothing

Establishes minimum performance classification and labeling requirements for protective clothing designed to provide protection against chemical hazards. Protective clothing items covered by this standard include, but may not be limited to, totally encapsulating suits, splash suits, coveralls, jackets, pants, aprons, smocks, hoods, sleeves, and shoe and boot covers.

ANSI/ISEA 107-2010

American National Standard for High Visibility Safety Apparel and Headwear Devices

This standard specifies performance requirements for high visibility safety apparel and headwear PPE. For the purpose of this standard, the term "garment" shall be used to mean apparel and headwear PPE. These garments are intended to provide conspicuity to the user in hazardous situations under any light conditions by day and under illumination by vehicle headlights in the dark. Performance requirements are included for color, retro reflection, and minimum areas, as well as the recommended configuration of the materials. Performance, requirements are also provided for the physical properties of background materials used in the construction of high-visibility safety apparel and headwear. Test methods are provided in the standard to help ensure that a minimum level of visibility is maintained when garments are subjected to ongoing care procedures.

CSA Z96.1-08

Guideline on Selection, Use, and Care of High-Visibility Safety Apparel

This is the first edition of CSA Z96.1, Guideline on selection, use, and care of high-visibility safety apparel. It is to be used in conjunction with CAN/CSA-Z96, High-visibility safety apparel.

CSA Z96-09

High-visibility safety apparel

This Standard specifies requirements for occupational apparel that is (a) capable of signalling the user's presence visually; and (b) intended to provide the user with conspicuity in hazardous situations under any light conditions and under illumination by vehicle headlights.

ASTM F1494-03(2011) Standard Terminology Relating to Protective Clothing

Standard Terminology Relating to Protective Clothing

This standard defines the specialized terms used in standards developed by Committee F23 on Protective Clothing

ISO/TR 11610:2004

Protective clothing - Vocabulary

ISO/TR 11610:2004 contains a list of terms which are frequently used in the standardization of protective clothing and protective equipment worn on the body, including hand and arm protection and lifejackets, and definitions of these terms. The definitions are intended to support an unambiguous use of the terms listed.

ISO/TR 2801:2007

Clothing for protection against heat and flame - General recommendations for selection, care and use of protective clothing

ISO/TR 2801:2007 sets out guidance for the selection, use, care and maintenance of clothing designed to provide protection against heat and flame.

NFPA 1992-2000

NFPA 1992: Standard on Liquid Splash-Protective Clothing for Hazardous Materials Emergencies, 2000 Edition

Covers design criteria, performance criteria, and test methods for Liquid Splash-Protective Suits designed to protect emergency response personnel against exposure to specified chemicals in liquid-splash environments during hazardous chemical emergencies.

NFPA 1992-2005

NFPA 1992: Standard on Liquid Splash-Protective Clothing for Hazardous Materials Emergencies, 2005 Edition

 This standard defines the specialized terms used in standards developed by Committee F23 on Protective Clothing.

ASTM F1301-90(2011)e1

Standard Practice for Labeling Chemical Protective Clothing

This practice covers the informational content of labels in or on chemical protective clothing. This practice details the recommended format and minimal content of the information to be included on the labels used for chemical protective clothing.

ASTM F1494-03(2011)

Standard Terminology Relating to Protective Clothing

This standard defines the specialized terms used in standards developed by Committee F23 on Protective Clothing.

ONORM EN ISO 13982-1:2011

Protective clothing for use against solid particulates - Part 1

Performance requirements for chemical protective clothing providing protection to the full body against airborne solid particulates (type 5 clothing)

BS EN 14605:2005+A1:2009

Protective clothing against liquid chemicals.

Performance requirements for clothing with liquid-tight (Type 3) or spray-tight (Type 4) connections, including items providing protection to parts of the body only (Types PB [3] and PB [4])

ISO 13688:1998

Protective clothing - General requirements

This International Standard specifies general requirements and recommendations for ergonomics, ageing, sizing and marking of protective clothing, and for information supplied by the manufacturer.

IEC 61482-1-1 Ed. 1.0 b:2009

Live working - Protective clothing against the thermal hazards of an electric arc - Part 1-1: Test methods - Method 1: Determination of the arc rating (ATPV or EBT50) of flame resistant materials for clothing

IEC 61482-1-1:2009 specifies test methods to measure the arc thermal performance value of materials intended for use in heat - and flame-resistant clothing for workers exposed to the thermal effects of electric arcs and the function of garments using these materials.

IEC 61482-1-2 Ed. 1.0 b:2007

Live working - Protective clothing against the thermal hazards of an electric arc - Part 1-2: Test methods - Method 2: Determination of arc protection class of material and clothing by using a constrained and directed arc (box test)

This part of IEC 61482 specifies methods to test material and garments intended for use in heat- and flame-resistant clothing for workers exposed to electric arcs. In contrast to the test methods in IEC 61482-1-1 a directed and constrained electric arc in a low voltage circuit is used to classify material and clothing in defined arc protection classes.

IEC 61482-2 Ed. 1.0 b:2009

Live working - Protective clothing against the thermal hazards of an electric arc - Part 2: Requirements

IEC 61482-2:2009 is applicable to protective clothing used in work if there is an electric arc hazard. Specifies requirements and test methods applicable to materials and garments for protective clothing for electrical workers against the thermal hazards of an electric arc

ISO 11611:2007

Protective clothing for use in welding and allied processes

ISO 11611:2007 specifies minimum basic safety requirements and test methods for protective clothing including hoods, aprons, sleeves and gaiters that are designed to protect the wearer's body including head (hoods) and feet (gaiters) and that are to be worn during welding and allied processes with comparable risks. For the protection of the wearer's head and feet, ISO 11611:2007 is only applicable to hoods and gaiters. ISO 11611:2007 does not cover requirements for hand protection.

ISO 11612:2008

Protective clothing - Clothing to protect against heat and flame

ISO 11612:2008 specifies performance requirements for garments made from flexible materials, which are designed to protect the wearer's body, except the hands, from heat and/or flame. For protection of the wearer's head and feet, the only items of protective clothing falling within the scope of this International Standard are gaiters, hoods and over boots. However, concerning hoods, requirements for visors and respiratory equipment are not given.

ISO 13982-1/Amd1: 2010

Protective clothing for use against solid particulates - Part 1

Performance requirements for chemical protective clothing providing protection to the full body against airborne solid particulates (type 5 clothing) - Amendment 1

ISO 13982-1:2004

Protective clothing for use against solid particulates - Part 1: Performance requirements for chemical protective clothing providing protection to the full body against airborne solid particulates (type 5 clothing)

ISO 13982-1:2004 specifies the minimum requirements for chemical protective clothing resistant to penetration by airborne solid particles (Type 5). These garments are full-body protective clothing, i.e. covering trunk, arms and legs, such as one-piece coveralls or two piece suits, with or without hood or visors, with or without foot protection.

ISO 14116:2008

Protective clothing - Protection against heat and flame - Limited flame spread materials, material assemblies and clothing

ISO 14116:2008 specifies the performance requirements for the limited flame spread properties of materials, material assemblies and protective clothing in order to reduce the possibility of the clothing burning and thereby itself constituting a hazard. Additional requirements for clothing are also specified.

ISO 14877:2002

Protective clothing for abrasive blasting operations using granular abrasives

Minimum requirements and test methods for protective clothing for abrasive blasting operations and for hand protection, for the treatment of surfaces with granular abrasives propelled by compressed air or by mechanical means. The protection against substances that develop during the blasting operation as well as connections between the protective clothing and the respiratory protective device are also covered.

ISO 16602:2007

Protective clothing for protection against chemicals - Classification, labeling and performance requirements

ISO 16602:2007 establishes minimum performance classification and labelling requirements for protective clothing designed to provide protection against chemicals. Protective clothing items covered by ISO 16602:2007 include, but may not be limited to, totally encapsulating suits, liquid-tight or spray-tight suits, coveralls, jackets, trousers, aprons, smocks, hoods, sleeves, and shoe and boot covers.

ISO/TR 11610:2004

Protective clothing - Vocabulary

ISO/TR 11610:2004 contains a list of terms which are frequently used in the standardization of protective clothing and protective equipment worn on the body, including hand and arm protection and life jackets, and definitions of these terms.

ISO/TR 2801:2007

Clothing for protection against heat and flame - General recommendations for selection, care and use of protective clothing

ISO/TR 2801:2007 sets out guidance for the selection, use, care and maintenance of clothing designed to provide protection against heat and flame.

[textilegfg]

Indian Textile Ministry to Promote Jute Fabrics for Rural Roads

The Union Ministry of Textile is planning to promote use of jute geo textiles for construction of rural roads across India.

Geo textiles are permeable fabrics used as an agent to strengthen the road foundations and prevent soil erosion along the banks. Jute geo textiles are said to be about 25% cheaper than other fabrics. However, this bio-degradable material is low on longevity and is best used in rural or arterial roads, which do not attract heavy traffic.

Road construction

According to a National Jute Board (NJB) official, jute-based textiles are currently in use in constructing 35 ongoing rural roads, under the Pradhan Mantri Gram Sadak Yojana, across the country.

While majority of the projects are in Karnataka, in South West India, the practice is gaining popularity in at least three other states, including Odisha, Madhya Pradesh and West Bengal.

Subrata Gupta, Jute Commissioner, said that the use of jute geo textiles is likely to move up substantially in the next two years. According to Gupta, project reports for nine roads spread across five states such as Chhattisgarh, Madhya Pradesh, Odisha, Assam and West Bengal have also been prepared.

Jute geo textiles production

Rough estimates available with NJB suggest that consumption of the fabric increased by about 10% a year since 2010.

In 2010, approximately 60 lakh square metres of jute geo textile were used in road development, a top official of the cell added. Out of the 80 odd jute mills operating across the country, 13 mills manufacture jute geo textile.

Despite efforts to promote the natural fibre, absence of a regulation for mandatory use of jute instead of synthetic textiles and lack of support from local administration pose challenges before the industry, it has been reported.

Challenges

“It is an uphill task to convince various agencies and engineers the benefits of jute geo textile unless there is a mandate,” the top official said.

According to him, it will also be difficult to involve more jute mill owners in production of the fibre until the demand situation improves.

Read the original story

[textilegfg]

Cylinder Dial and Rib with V Bed

[textilegfg]

Actions of Sinker

[textilegfg]

Knit Tuck Float Stitch

[textilegfg]

Needle Action

[textilegfg]

Socks Knitting- Animation

[textilegfg]

M FACTOR AND C FACTOR : Developments in Cleaning Ranges at Blowroom

M FACTOR AND C FACTOR

New cleaning ranges have been introduced as compared to those using nipped beating points. Today’s modern ranges of machines have drastically reduced such beating points. Modern harvesting (m/c picked) and ginning (broken seeds) has made cleaning in the preliminary stages much more difficult, even when the trash, by weight itself, is much less. As against this, the demands for today’s cleaning are increasing. Presently, therefore, the modern machines are designed to carry the work of three to four cleaning machines working in tandem of yester years.  Cleaning performance of the machine can’t be judged objectively as the cleaning does not merely depend upon the machines alone; but on cotton and its varying properties. In fact influence of the latter is as great as that of former.

In designing modern cleaners, the methods have been developed to differentiate between the various influences and to classify them by numerical values. With these, it has now been possible to give a specific value – Factor M to a machine’s performance i.e. the cleaning effect of that machine. 

Cleaning Factors: The quality of cotton factor C is of equal importance to the cleaning effect. It indicates whether a cotton is easy or difficult to clean. Another important factor is the trash content (T). Under the identical mill conditions, the degree of cleaning by a machine is higher, when cotton is dirty than when it is clean. This is factor T & it represents % of trash.

With a low trash content (say 5%), the degree of cleaning (Rg) may be roughly calculated by using the following equation:

Rg = M. C. T

For higher trash content, a more accurate figure can be derived as:

The factor M for different machines has been determined by comparing their performance with present Trutzschler Cleaner RN with nose beater & grid eliminator – M = 1. Likewise, the value for C were found by cleaning tests on standard cleaning machines and comparing the results with mean standard for cotton, valid for some 5 years ago - - C = 1. The factor ‘T’ was directly determined with Shirley Analyzer.                    

On the basis of these factors, machine influence as well as cotton influence may now be separately determined accurately. This helps in solving specific cleaning problems and developing expedient machines.

The correlation between the various factors is illustrated by the different graphs:

The cotton (with C=1) was passed through at 350 kg/h and degree of cleaning was plotted on Y-axis. This graph shows that for a trash content of 3% (in the material fed to the machine), a cleaning degree of 30% was obtained. Whereas the same machine reaches only 10% cleaning when the trash content is 1%, other conditions being the same. The machine’s rating is then derived as M = 1.The higher the cleaning effect of the machine, the steeper is the characteristic line.

As per this graph, M1 = 1; M2 = 1.5 & M3 = 2.

In this case factor C, when cottons are tested, is 1. Here, the machine factor M = 1 and is kept constant by using one and the same machine. The C factors are found to vary from 0.5 to 2.0 Thus, a value of 0.5 reflects that the cotton is difficult to clean; whereas a value of 2.0 shows that the cotton is easy to clean. Steeper curve means that the cotton is easy to clean.

The values of C obtained under the mill conditions on Saw-Tooth Cleaner RSK for different cottons. The line on the right hand-most characterizes a cotton where C = 0.6. Another line next to it stands for C = 1. Another line to the extreme left is for C = 2.0.This factor C have become worse over last few years and now a days, the value of C = 0.2 (very difficult to clean) is frequently found. The values of C obtained under the mill conditions on Saw-Tooth Cleaner RSK for different cottons. The line on the right hand-most characterizes a cotton where C = 0.6. Another line next to it stands for C = 1. Another line to the extreme left is for C = 2.0. This factor C have become worse over last few years and now a days, the value of C = 0.2 (very difficult to clean) is frequently found.

The cotton with C = 1 contains coarse, little damaged leaf and stem-remainders, all of which are loosely attached to the top surface of the tuft during opening process. Therefore, this cotton is easy to clean, as some of these impurities readily fall-out even when the opening is carried out by hand. The cotton with C = 0.2 contains trash which is crushed into extremely fine fragments. These fragments disperse like wadding-like cotton. The tiny fragments are surrounded by the fibres, thus holding them tenaciously. They very rarely fall-out even when opened by hand. It can be understood that the cleaning effect of a machine can’t be correctly assessed, simply giving a figure for the ‘Degree of Cleaning’. For this, the cotton characteristics & method of preparation need to be taken into account. Factor C depends to a high degree on cotton’s provenance (place of origin), maturity level & its preparation. This (C) factor is also liable to change during the process, especially with different cleaners used in blow room line. These factors will have to be taken into account to arrive at a suitable value of C.

Let the following equation be again looked at.

Rg = 10. M. C. T

With   M = 0.5, 1.0, 1.5   &   C = 0.5, 1.0, 1.5 

Only in extreme cases, C was found to have as low value as 0.2 and as high value of 3.0. The machine factors –M were ranging between 0.5 & 1.0 this shows that the influence of cotton characteristics on its getting cleaned has been far more than machine factor. Using the above equation, cleaning curve for specific cleaning range is plotted. Calculated & measured curves tally reasonably well. The cleaners R1 to R3 are in series. Along with card K, they achieve a degree of cleaning indicated by respective columns. The line indicates a cumulative degree of cleaning obtained at every cleaning stage.

Moisture content and production rate have decided influence also.

All the above discussion is based on production rate of 350 kg/h for cleaners in BR & 40 kg/h for card. Even then, the present methods are suitable for delineating (describe or portray) the cleaning potential and their range.

Comparisons of different Cleaning Machines:

The RN cleaner, with nose beating, achieves cleaning degree of 10% at 1% trash content. Consequently, its machine factor M = 1. The saw tooth cleaner RSK achieves 15% cleaning at 1% trash content; hence its machine factor M = 1.5

Action of RST Cleaner:

This machine is saw-tooth cleaner. It show 33% cleaning with trash content in the cotton as 1%. Evidently, its machine factor M = 3.3. It is obvious that RST is distinctly more efficient than a machine with say, M-factor = 1.65. The total cleaning effect of the two cleaners, working in a series has to be determined. It is usually found that this effect is always lower than the sum of the two machines taken separately. The same applies to the machine factor – M. It follows that the cleaner RST with M = 3.3 is plainly twice as effective as RSK with M = 1.5.

RST is the second highly effective machine further to the development of established RSK. It doesn’t require transporting the material through ducts, intermediate storage bins etc. The adjoining graph gives the behavior of the beater in cleaning the cotton. As mentioned earlier, with 1% trash, the cleaning level reached is around 33%

In ingenuity of the action of RST is that for the cylinder, two mote knives are fitted. They are further followed by a carding plate. Up to this the cleaning effect is the same as that of RSK. RST, however has the continuous suction system. This prohibits any possibility of trash and dust back into the material.

Another difference is that there is doffer which transfers the material from cylinder and subsequently; the stripper, which rotates at high speed and which again is equipped with mote knife and suction hood eliminates further trash. The interplay between feed rollers (the lower one has saw-tooth clothing), cylinder, doffer & stripper follows the laws of gentle carding technology. In RST, the mechanics of trash extraction consists of centrifugal force combined with suction in the region of mote knives. This achieved through careful and well-designed stages by determining peripheral speeds& type of clothing. This induces terrific cleaning effect at the last stripper. The width of the aperture in front of mote knife is yet another factor with RST.

With all these arrangements, it is possible to tune RST to different cotton qualities & cleaning requirements by exchanging the covers between knives and cylinder. This is rarely done because it is troublesome.. The latest RST now has lever controlled mote knives wherein the turning is either manual or through servo-motor and this can be done during machine running. With servo-motor, the mechanism is computer controlled. The data for cotton varieties for this setting can be stored (& can be recalled) or integrated through microprocessor, which also controls the speeds & extraction condition in the areas of waste removal & material transfer  RST distinguishes itself from other conventional cleaners, not only by its high cleaning effect, but it also extracts only a small amount of useable fibres. It is known that in the beginning of any cleaning range, the waste extracted contains a small proportion of good fibre waste. However, in the last stages, especially with saw-tooth technology, good fibre loss in the waste continuously increases. This is also true for card. The new m/c – RST – giving a high degree of cleaning, gives only 20-25% fibre content which is no longer useable, & therefore, to be eliminated , anyhow.  With RST, there is appreciable reduction of waste at card as well, thus improving the yield at that stage. It was thus confirmed that opening & cleaning must be taken as a whole and the various stages need to carefully balance. The first step in opening & cleaning should be removal of coarser impurities. The successive stages should aim at reducing the cotton tufts progressively finer. With properly balanced steps, only a few machines in the range suffice the purpose. People are always apprehensive about the machines with saw-teeth, as they think that it will either damage the fibres or lead to more nep generation. However, this apprehension stems from faulty choice of saw clothing and wrong technology within the machine. (Wrong speeds or not adopting progressive fineness of saw teeth or faulty management of air currents.) Mill tests have shown that like other machine, RST also produces (more) neps. But except carding & combing, the neps do increase in Blow Room. The tensile strength of the yarn & other useful characteristics have remained unchanged. It is necessary to install metal detectors and extractors in the range for protecting saw teeth. Also, it is necessary to replace the clothing, once in two years. The clothing on the main cylinder is very robust to protect from damage & eliminates coarser impurities. 

Card as a Cleaning Machine: Apart from individualization, being the main object, the card is also a cleaning machine. There are considerable improvements at the card. The small particles and dust, separated by mote knives and carding segments, are immediately removed by suction. One may be tempted to use two saw tooth cleaners for better results. If the first cleaner is (say) Axi-Flow or RN, both having lower cleaning effect, the new RST still justifies its position, This is because, it easily removes coarse impurities, without crushing them. The smallest and varying particles of trash are of more concern than the total weight of impurities. This is because, the mere weight of impurities does not give correct idea of judging and improving cleaning operations.

There has been constant improvement in the cleaning range used in the blow room line. The graphs shows four cleaners of equal specifications. The degree of cleaning in each successive stage diminished as the material flowed. Beaters being same in the nature, it made extraction of the trash at succeeding stage more difficult. Therefore the total cleaning effect before reaching to card was around 35%. As is known, whatever, blow room leaves, the card tries to complete (at what cost is the question). Therefore, the card showed drastic improvement. This was in 1962.

In 1984, saw-tooth cleaner RSK was introduced. The typical line shown in the earlier curve disappears. In this case, using only three cleaners gave 53% cleaning (+18%), what the earlier four cleaners could not give. In the third graph, using only one cleaner RN, there was second cleaner RST. The graph speaks for itself. It is clear from this graph that RST has almost taken over the function of the card.

 Integration of RST into Cleaning Range:

The fig. below, shows the integration of RST into a cleaning range. In this line, the principle of successive opening & cleaning is rigorously followed.

After Blendomat (BD T 019), there is Blending Hopper (BOBS). The material from this is emptied by inclined spike lattice, follows a light beating against the grid and gets fed to RN Cleaner.

Through exhaust condenser cage, the material enters four-chamber blending machine. The material, in quite opened condition, produces a feed, in which, blending size of the tuft, composition & uniformity are indeed ideal. The uniform lap sheet then enters RST. The material from RST meets all the pre-requisites for uniform feeding to the card. The suction from RST is connected to dust extractor DX. Finally, the material is led into chute feed to the card.

CONCLUSIONS A. With RST, ideal conditions are obtained, apart from thorough cleaning of the trash and dust, to feed the card. B. The suction fan provided around RST, allows no lingering of extracted waste. C. The reduction in the tuft size augments much improved functioning of card. D. The flow of the material within any cleaning range has a considerable influence on cleaning performance of the range of machines used in Blow Room. E. The use of microprocessors to constant and continuous flow of the material is very essential for intensive and yet gentle treatment. This means that all the cleaners operate without stopping and adjust themselves by infinitely variable drive to the required feeding rate.

[textilegfg]

Textile in Sports

1. Introduction to Textile in Sports

Textile materials are used in virtually every sports. Today’s sports demand high performance equipment and apparel. The light weight and safety features of sporttech have become important in their substitution for other materials. These high-functional and textiles are increasingly adding value to the sports and leisure industry by combing utilitarian functions with wearing comfort that leads to achieving high level of performance. Textile manufactures today are giving themselves an edge in the increasingly competitive sports and recreation market. Use of textile structural composites in sporting goods is increasing. This is due to their high strength and durability.

Textile materials are used in all sports as sportswear, and in many games as sports equipment and sports footwear. The examples of sportswear are: aerobic clothing, athletic clothing, football clothing, cricket clothing, games shorts, gloves, jackets, pants, shirts, shorts, socks, sweat shirts, swimwear and tennis clothing. The examples of sport equipment are: sails, trampoline, camping gear, leisure bags, bikes, and rackets. The examples of sports footwear are: athletic shoes, football boots, gym shoes, tennis shoes and walking boots.

2. Requirements for Sports Textile Materials [1]

The main requirement of material which is used for sports materials should be comfort to the players.

The main technical consideration for coated or laminated protective sportswear in addition to basic fabric properties such as colour fastness, aesthetics and design are:

Handle /flexibility

Tear & tensile strength(or bruiting strength)

Abrasion resistance (to cold water and washing)

Flame resistances

Resistance to delaminating (good coating)

Waterproof-ness

Breath-ability

Spay rating

low weight

General durability/ flexing

Easy care

 3. Physiological Comfort of Sportswear [3, 9, 10]

Comforts is the most important factor in clothing and especially for sportswear, producers who are able to convince the end use of their product’s comfort benefits, in particular directly at the point of sale, have an advantage.

3.1. Comfort

Many attempts have been made to define comfort, but a satisfactory definition is yet to be obtained. Comfort has been defined by many researches in different ways.

Comfort is influenced by the physiological reaction of the wearer.

Comfort is temperature regulation of the body.

Comfort is the absence of unpleasantness or discomfort.

Comfort is a state of pleasant psychological, physiological and physical harmony between a human being and the environment. All these aspects are equally important. If people feel that uncomfortable then there is absents of any one of them.

There are four basic elements of clothing comfort

Thermo – physiological aspect

Transmission of heat, air and moisture (liquid and vapour)

Sensorial (or) tactile aspect

Mechanical contact of the fabric with skin

Physiological aspect

Aesthetic properties of fabric (i.e.) drape, luster, colour, crease, pilling, staining, etc..,

Fitting comfort

Size and fit of clothing

4. Fibres Used For Sport Textiles [5]

Three-dimensional bands in polyester used for sports footwear

Bands in Kevlar, carbon, fibreglass, and aramid fibres used as inserts in sports accessories

Carbon ribbons used for sports articles or components

Carbon ribbons used as reinforcements for sports helmets

Carbon inserts for racing footwear

Polypropylene, polyester, rubber, cotton and rafia netting

5. Textile Materials used in Different Sports [1]

5.1. Baseball

Baseball, though an extremely traditional sport, has not escaped the invasion of high technology. The technology in baseball involves the ever-important baseball bat. Engineers have worked to develop composite baseball bats of two types.

5.1.1. Graphite composite bat

The graphite composite bat is made on automated filament winding machines. These machines precisely position strong graphite and glass fibres that are subsequently bonded together with epoxy resin to create a hollow bat structure.

5.1.1. Wood composite bat

The wood composite bat is made up of a high strength inner core fabricated from resin impregnated synthetic fibres and yarns, integrated with an ash wood outer surface.

5.2. Tennis

Todays, tennis rackets are going through some remarkable changes in design of racket. The first composite tennis racket is made of fiberglass composite. Since then there has been tremendous growth in the use of many different textile composite in racket design. The manufactures combined fiberglass with other fibres graphite and ceramics in an attempt to increase the strength and durability of the rackets.

Graphite is current top choice material that combines both lightweight and durability increasing both power and control of the racket. These are 5 times stronger than aluminium once. Other space aged fibres such as Twaron, boron and Kevlar are combined with high performance carbon producing an excellent racket. These are six times stiffer than steel and five times stronger than aluminium.

Tennis balls are made of woven and needled tennis felts. Slit film fabrics are used for wind break screening for outdoor courts. Tennis net is made of very durable polyethylene monofilament fibres.

5.3. Football

There is problem in the traditional ball during cold weather.

The design of football was revolutionized with the use of textile composites. The bladder of the football was made of a multi-layer arrangement of polyurethane. This increased the strength and durability. This lining is made of especially high performance spun polyester. The seams of football are made of Kevlar. The polyurethane does not deform like the conventional butyl rubber bladder.

5.4. Golf and Hockey Equipment

Golfer discovered high performance clubs made of graphite composites. With this improvement in the use of graphite, the flexibility has been greatly increased. Some prominent clubs consist of a mixture of boron and graphite shafts with a high modulus of elasticity. The high modulus and high strength make for a lighter, stiffer shaft. These are very desirable qualities which composites offer to improve the sport of golf. Hockey sticks are made of textile structural composites.

5.5. Bikes

Bicycling enthusiasts believe that the bike frames should be as rigid as possible to prevent the loss of energy and unstable steering. The flexible frame allows for the absorption of the shocks of a mountain bike. The elastic properties of the composite enable the frame to elongate and shorten, while the coil spring compresses and extends. The glass fibre composite attached to the frame of the bicycle acts as a spring to the frame elongation and energy storage. High performance composite materials which have both flexural strength and fatigue resistance increase the durability of bikes. These composites are now used widely in mountain bikes and racing bikes.

5.6. Marine Products [14]

Textile materials are used in various marine products for function and fashion purpose including mooring covers, boat tops, shading, sail covers. The requirements for these textiles include low stretch, high strength failure along with good resistance to weather aging and chemicals, and material must be waterproof.

Woven polyester fabric- has low stretch achieved with elimination of crimp; high tenacity and high initial modulus yarns are used with a plain weave. Woven nylon fabric- main properties are lightweight, limited porosity, good breaking and tear resistance using a plane weave and can be coated to control porosity. Laminates with oriented polyester film. Exotics such a carbon fibre and layered composites.

Spectra and carbon fibres are used in high performance sailboats such as the stars and stripes.

5.7. Field Cover [13]

 Textile field covers are used to protect the playing surface from rain, snow, blistering sunshine and freezing winds. Fabric weight is critical for field covers. The cover must be light enough to move around but heavy enough to withstand severe weather condition. Polyvinyl chloride is widely used as a coating and laminate. PVC provides waterproof-ness mildew resistance and protects the fabric from ultraviolet rays. Polyester and nylon are most popular common materials as supporting fabrics in cover. Polyester offers good dimensional stability at different temperatures and good UV resistance. Nylon is considered to be more suitable for field cover than the polyester but it is prone to shrinkage.

6. Waterproof Breathable Active Sportswear Fabrics [2,4]

Waterproof breath fabrics are designed for use in garments that provide protection from the environment factors like wind, rain and loss of body heat. Waterproof fabric completely prevents the penetration and absorption of liquid water. Fabrics that can convey water vapour from body perspiration out through the material while remaining impervious to external liquids such as rainwater are widely used in sportswear and similar applications.

Water-resistant and moisture-permeable materials may be divided into three main categories - high-density fabrics, resin-coated materials and film-laminated materials - which are selected by manufacturers according to the finished garment requirements in casual, athletics, ski or outdoor apparel.

6.1. Densely Woven Water Breathable Fabrics

The densely woven waterproof breathable fabrics consist of cotton or synthetic microfilament yarns with compacted weave structure. One of the famous waterproof breathable fabrics known as VENTILE was manufactured by using long staple cotton with minimum of spaces between the fibres1. Usually combed yarns are weaved parallel to each other with no pores for water to penetrate. Usually oxford weave is used. When fabric surface is wetted by water the cotton fibres swell transversely reducing the size of pores in the fabric and requiring very high pressure to cause penetration. Therefore waterproof is provided without the application of any water repellent finishing treatment. Densely woven fabrics can also be produced from micro-denier synthetic filament yarns.

The individual filaments in these yarns are of less than 10 micron in diameter, so that fabrics with very small pores can be engineered.

6.2. Laminated Waterproof Breathable Fabrics

Laminated waterproof breathable fabrics made by application of membranes into textile product. These are thin membrane made from polymeric materials. They offer high resistance to water penetration but allow water vapour at the same time. The maximum thickness of the membrane is 10 micron. They are of two types:

1)    Micro porous membranes

2)    Hydrophilic membranes

6.3. Coated Waterproof Breathable Fabrics

Coated fabrics with waterproof breathable fabrics consist of polymeric material applied to one surface of fabric. Polyurethane is used as the coating material. The coatings are of two types:

1) Micro porous membranes

2) Hydrophilic membranes.

6.4. Performance of waterproof breathable fabrics

Many research has been compared the performance characteristics of different types of waterproof breathable fabrics. After the general conclusions are

Breathable materials are very much better than fabrics coated with conventional waterproof materials.

Breathable fabrics have higher resistances to vapour transport than ordinary woven and knitted apparel fabrics.

Some waterproof breathable fabrics have a lower vapour resistance than some ordinary apparel fabrics.

7. Sportswear for Active Adults goes Hi-tech as Vital Eco-wear redefines Fit-for-purpose Design [7]

Vital eco-wear is developing innovative fabrics incorporating state-of-the-art, bio-functional fibres to produce garments that introduce a new level of fit-for-purpose sportswear. Employing techniques based on Nano-technology, computerized body mapping, and the textile industry's latest equipment for seamless manufacture, vital eco-wear sportswear is designed to meet the particular needs of the type of sport. Each garment incorporates different combinations of fibres and knits to respond to the varying needs of different parts of the body. "Whether the particular body area needs extra support, enhanced stretch, or extra ventilation, the garment will be designed to seamlessly match every need."

Each of Vital eco-wear's 4 product lines

Yoga & More,

Workout & Fitness,

Outdoor Action,

Winter Sports

Yoga & More garments are made from ecologically-friendly fabric eco-DEOSOFT - a super-soft fabric containing natural bamboo fibres with anti-bacterial properties that keep the garment naturally fresh and deodorized, while the fibres micro-gaps let the skin breath.

The new Workout & Fitness fabric, Eco-COMFORMANCE, consists of bamboo, micro-polypropylene and elastin, offering high performance with enhanced comfort. In addition to the natural fibres anti-bacterial properties and micro-gaps that let the skin breathe, extra elastin gives these garments the needed elasticity for stretch and control.

Outdoor Action garments are made from Eco-AERODRY - an eco-friendly fabric based on recycled materials, using activated carbon from coconut shells. This gives the fabric high performance properties including wicking, or drawing moisture away from the skin for quick evaporation on the fabric's surface, odor absorption, and even natural UV protection. Eco-AERODRY is designed to keep the wearer cool, dry and fresh.

To meet the needs of Winter Sports, geared toward a more extreme form of outdoor sports, vital eco-wear developed Eco-THERMAL, a fabric consisting of BeCool™ polyamide, polypropylene and elastin. In addition to its advanced temperature regulating properties keeping the body dry and warm, Winter Sports garments include seamlessly built-in areas of extra protection and 3D stretch.

8. High-tech Sports Clothing with a High Comfort of Use Made from Multi-layer Composite Materials [6]

 Textiles designed for sports cloth­ing should perform several very different, and even mutually ex­cluding, functions. On the one hand, they must protect their users against heat loss, overheating or soaking, and on the other hand they must meet high requirements in respect of product durability, as well as many other properties contributing to the comfort of use. First of all, such characteristics include:

Protective properties against variable atmospheric conditions existing dur­ing the clothes’ use, as well as protection against physical damage, A high resistance to external influences, including tear strength, resistance to abrasion, shape stability, colour fast­ness, making-up quality, constancy of protective functions, and other features contributing to the service life of such materials, Comfort-providing properties, generally described as wellness, including first of all physiological comfort. This includes protection against over-warm­ing or -cooling, owing to high water vapour permeability, i.e. carrying off perspiration, good warmth retention and adequate air permeability. Moreo­ver, the user’s feeling is positively af­fected by soft handle and good shape assumption by the fabric and cloth cut that does not limit the user’s ease of movement, as well as the cloth’s aes­thetic appeal and practical constancy of protective and aesthetic functions throughout the period of use.

It is rather difficult to make all the men­tioned features compatible, and opti­mised solutions can be found only by us­ing composite materials, i.e. multi-layer systems with appropriately selected types and characteristics of the component ma­terials used to manufacture clothing of that type.

8.1. The multi-layer model system [11]

The model systems consist of three layers: an external or top layer, a middle layer that functions as a barrier, and a back lay­er. Usually described as the lining. These layers are joined together, either by the technique of point laminating or while making up the clothing, to form a spe­cific multi-layer composite material.

The top layer must show good physical and mechanical properties to provide durable protection of the user against all external, mechanical and atmospheric effects, as well as great aesthetic ap­peal and as high a constancy as possible throughout the whole period of use. This layer, depending on its structure and raw materials, can also fulfil barrier functions, including resistance to wetting and water penetration inside the composite material, as well as windproof capability. A typical example of such a material may be woven fabric made from multi-filament polyes­ter yarns, principally micro-fibres, with a high structure cover factor and high strength, sometimes with an additional waterproof finish or soil-release finish.

The middle layer, with barrier proper­ties, can be of two basic types:

a) A water- and windproof layer consist­ing usually of polymeric membranes or coats on a carrier such as polyester knitted fabric, with high water vapour permeability and low air permeability. Mostly, these are water- and wind­proof and simultaneously ‘breath­ing’ micro-porous hydrophobic polyurethane coats/membranes with a high water vapour permeability or hydrophilic coats/membranes with a compact structure and a generally lower water vapour permeability, but higher water-tightness. Both types of materials are made by the technique of reversible coating and transferred onto light, usually knitted textile carriers.

b) A thermo-insulating layer with a high warmth retention, used in sports cloth­ing to be used under lower temperature conditions (e.g. in the spring/autumn or winter periods). This layer mostly consists of fluffy polyester non-woven fabric or raised knitted fabric of the Polar type. These knitted fabrics have single-sided or two-sided developed piles, usually from polyester micro-fibres. Their fluffiness provides particularly high warmth retention.

The back layer of the system, fulfilling the role of lining, may for example be a thin polyamide woven/knitted fabric, but Polar knitted fabric or fur fabric is also possible.  

9. Development in Textile Materials for Sportswear [8]

9.1. Fibre Developments

The evolution of fibre developments have gone through the phases of conventional fibres, high functional fibres and high-performance fibres. Polyester is the single most common fibre used for sportswear and active wear. Other fibres suitable for active wear are polyamide, polypropylene, acrylics and elastanes. Fibres from renewable resource based polymers such as corn-based polylactide (INEGO) and polytrimethylene terepthalate (SONARA) as well as wood-fibre based Lyocell are also finding markets in the sport and leisurewear market sectors. Wool and cotton fibres are still finding applications in leisurewear. Synthetic fibres can either be modified during manufacture, e.g., by producing hollow fibres and fibres with irregular cross-section or optimally blended with natural fibres to improve their thermo-physiological and sensory properties. Synthetic fibres with improved UV resistance and having anti-microbial properties are also commercially available for use in sportswear.

9.2. Yarn Developments

Improved fibre spinning techniques in melt spinning, wet spinning, dry spinning as well as new techniques such as gel spinning, bi-component spinning, micro-fibre spinning have all made it possible to produce fibres, yarns and fabrics with unique performance characteristics very suitable for use in sportswear and sport goods. New technologies for producing micro-fibres have also contributed towards production of high-tech sportswear. By using the conjugate spinning technique, many different types of sophisticated fibres with various functions have been commercially produced which has resulted in fabrics having improved mechanical, physical, chemical and biological functions. The technique of producing sheath/core melt spun conjugate fibres has been commercially exploited for producing added value fibres.

9.3. Fabric developments

There has been a strong growth in development and use of high functional materials used in sportswear and outdoor leisure clothing. The performance requirements of many such products demand the balance of widely different properties of drape, thermal insulation, barrier to liquids, antistatic, stretch, physiological comfort etc. The research in this field over the past decade has led to the commercial development of a variety of new products for high functional end-uses. By designing new processes for fabric preparation and finishing, and as a result of advances in technologies for production and application of suitable polymeric membranes and surface finishes, it is now possible to successfully combine the consumer requirements of aesthetics, design and function in sportswear for different end-use applications. Many smart double-knitted or double-woven fabrics have been developed for sportswear in such a way that their face closer to human skin has optimal moisture wicking and sensory properties whereas the outer face of the fabric has optimal moisture dissipation behaviour.

In addition to the innovations in highly functional manmade fibre based fabrics, advances have also been made in cotton and wool fabrics for sportswear.

The light-weight breathable high functional fabric has been developed world wide. Today there are two main technologies for achieving waterproof breathable fabrics; microporous coating or laminates and hydrophilic, non-porous moisture –drawing coating or laminates. High functional fabrics are generally characterized as being waterproof/moisture permeable, sweat absorbing and with high thermal insulation at low thickness values. These fabrics are now extensively used in making sportswear and sports shoes. The hydrophilic polyester membrane is vacuum vaporised with aluminium to achieve a high level of body heat reflection in the garment. In these types of laminated fabric, multi-functionality in one and same material is obtained as characterized by thermal insulation, breathability, perspiration transport, absorption and quick dry properties.

Laminated fabrics made from monolithic breathable membranes which react to build up of heat and moisture If the micro-climate temperature rises, the openings between the polymer molecular segments expand thereby increase the moisture permeability of the laminated fabric. As the temperature then drop, the pores in the fabric close thereby trapping heat in the micro-climate surrounding a person.

9.3.1 Stretch Fabrics

Today’s garments with high stretch and recovery for sportswear play an important role in optimizing an athlete’s performance by providing freedom of movement, maximizing comfort, minimizing the risk of muscle fatigue and reducing friction or drag.

Fabric stretch can be achieved by a number of different methods. These include

Fibre elongation characteristics derived from its molecular chain geometry as in the case of synthetic elastomers known as elastane,

Bi-component polymer spinning which can create fibres with a helical crimp,

Yarn crimping such as texturing,

Fabric structures such as circular knits and

Finishing such as stretch silicone treatment or application of stretch laminates.

Recovery of a fabric after stretching is as important as stretching.

For many applications in sportswear there is need for less comfort stretch as compared with elastane fibre such as Lycra, but more comfort stretch than obtained using standard mechanically textured yarns. Today some stretch yarns are available which have been manufactured by using the bicomponent spinning technology. The two polymers in either side-by-side or sheath-core configuration in such bicomponent fibres, have inherently different rates of shrinkage. When such yarns are subjected to steam or high temperatures, they undergo self-crimping and long-lasting stretch and recovery properties.

The PTT (Polytrimethylene terephthalate which is aromatic polyester made by the polycondensation of 1, 3-propranediol (PDO) and terephthalic acid. PTT fibres show a significantly higher level of elastic recovery compared with PP and PET fibres. With the advent of new types of stretch fabrics having a range of stretch and recovery from low to very high, it is now possible to engineer seamless and stitchless casual and performance sportswear with variable stretch/power dependant on their applications.

10. Conclusion

The sportswear industry and its material suppliers are the foremost leaders of innovative product development within the textile and clothing sector and has been a launching pad for many new ideas and concepts in material and product design. The casual and performance sportswear of today have become truly engineered products designed to fulfil the consumer’s requirements of multi-functionality within the spectrum of comfort, lightweight, soft, injury–preventive, thermoregulatory, elastic, antimicrobial, durable and aesthetic.

11. References

Wellington series handbook of industrial textiles by Sabit Adanur published by technomic publishing company pg.no. 475 - 490

Handbook of technical textile by A.R.Hookcocks and S, C, Anand published by woodhead publishing limited pg.no. 282 - 314

Science in clothing by Apurba Das and R.Alaginusamy

www.sarmira.org/sportwear.pdf

www.comez.com/pdf/presentazione_2009_tt_en.pdf

www.fibtex.lodz.pl/52_21_90.pdf

www.pr_inside.com/sportswear-for-active-adults-goes-hi-tech-r98077.htm

www.jbfi.org/admin/issue/TBIS%202008_2008930152502_paper.pdf

Indian journal of fibre and textile research, vol.34 march 2009

Textile progress vol.9 number.41977, comfort properties by K.Slaten

Textile-polymeric multi-layer composites prepared by the techniques of coating and lamination designed for sports clothing with a high comfort of use, Part I, 4. 2004, pp. 15-17, Part II, 5. 2004, pp. 16-17, Part III 6.2004, pp. 18-19, Part IV, 1.2005, pp 13-15, by S.Brzeziński, G.Malinowska , K.Roba-czyńska

The textile institute, textile terms and definitions, tenth edition, textile institute, Manchester, 1994

The big ball field cover – up, industrial fabric products review, November 1986

Low – strength fabrics for sail making and other applications, IFAI second international high per–formance fabrics, conference, November 1992.

[textilegfg]

SPRAY-ON FABRIC - New INNOVATION

Spanish fashion designer Manel Torres invented the world's first clothes-spray, which after application to the body can be removed, washed and worn again.

Ref: The Textile Excellence, August 1-15, 2013.

[textilegfg]

Nanotechnology in Textiles

INTRODUCTION

 Surface structure and behavior of fibers are of the utmost importance for the properties of fibers and textiles in processing and use, since friction, abrasion, wetting, adhesion, adsorption, and penetration phenomena are involved. In order to obtain textile materials with the desired performance, the fiber surface is often modified with polymer layers before use. However, further advances in industrial textiles impose requirements for the modification that frequently are in conflict: a given textile material, depending on the conditions under which it is utilized, has to be hydrophobic or hydrophilic, acidic or basic, conductive or nonconductive, deliver or adsorb some species, change color etc. Our idea is to create “intelligent” hybrid polymeric coating for fibers and textiles, which could demonstrate a number of specific functions. An effective means to build the covering is to combine in one coating several “smart” polymer systems. Then, every component of the nanostructured hybrid layer will play its specific role and support versatile behavior of the textile material. It is clear that fine tuning of the properties of a particular fiber or textile material to its anticipated use requires the ability to regulate the morphology of the hybrid nanolayer. Indeed, several immiscible polymers constituting the sub-micron heterogeneous film can be organized in different manner on the fiber surface, and, consequently, the structure and properties of the hybrid coating made of the same components may be altered in a wide range. It is an important task to stabilize the morphology once the required properties of the hybrid nanolayer are reached. Thus, the elements of the coating have to be firmly attached to the surface and the layer has to have only some definite degree of freedom to perform the required tasks.

Grafting Technique for Synthesis of Polymer Films

Chemical grafting approach for the generation of the hybrid nanolayers have chosen. The grafting allows easy and controllable introduction of new polymer chains with a high surface density, precise localization of the chains at the surface, and long stability of the grafted layers, since covalent attachment can prevent delamination of the grafted layer in a liquid media. For successful building of the hybrid polymer layers, at least part of the coating has to be grafted to the fiber surface, namely a primary grafted layer has to be created. It is necessary to stress that a primary grafted polymer layer consisting of several polymers can itself serve as a hybrid responsive/adaptive coating. In other strategies, it can be a decisive part of the heterogeneous nanolayer. Basically, this ultrathin grafted film will direct the formation of the very first monolayer of coating, which is in contact with the surface and be a guide for further coating organization.

There are two main duties of the primary grafted film:

(a) Ensure strong adhesion between the fiber surface and components of the hybrid coating;

(b) Control the morphology of the multicomponent covering.

Generally, if we know how to regulate the morphology and properties of the primary layer, we can create adaptive materials straight away or have the ability to direct the other coating components to the right position on the fiber surface. Therefore, the first stage of the investigation was devoted to synthesis of the primary grafted polymer layer on the surface of the fibers.

The second stage of the project concentrated on the deposition and self-organization of the polymer hybrid layer on the model and fiber surfaces. Model and stimuli-sensitive polymers were used at this stage. First of all, we targeted the generation of the hybrid coverings with different levels of heterogeneity.

At the third stage of the present study we were focusing on the characterization of the hybrid nanolayers produced from the stimuli-sensitive polymer systems. Binary and ternary hybrid nanolayers of different morphologies were produced on the model and fiber surface. The morphology and level of heterogeneity of the covering was correlated with the ability of the different components to perform their functions.

PGMA as Universal Anchoring Interlayer.

We studied the permanent grafting of polymer nanolayers onto a polymeric substrate surface. The grafted layers were built in two steps. Poly (glycidylmethacrylate) (PGMA) was used for initial surface modification. We have chosen PGMA with epoxy functionality, since the epoxy groups are quite universal. They can react with different functional groups (carboxy, hydroxy, amino and anhydride) that are often present or can be created on the surface of various fiber and textile materials. The epoxy groups of the polymer chemically anchor PGMA to the fiber surface. The glycidylmethacrylate units located in the “loops” and “tails” sections of the attached macromolecules are not connected to the fiber surface. 

These free groups serve as reactive sites for the subsequent attachment of polymerization initiators and/or polymer with functional groups, which exhibit an affinity for the epoxy modified surface. We studied attachment of PGMA to various surfaces and found that the epoxy containing polymer layer could be permanently deposited on polymeric (PET, polyethylene, silicon resin, nylon) and inorganic (silicon, glass, titanium, alumina, gold, silver) surfaces by adsorption or dip-coating.

Synthesis of Layers Various with Thickness and Grafting Density Gradients

A novel approach was developed for the synthesis of tethered polymer layers with thickness and grafting density gradients. Poly (glycidyl methacrylate) (PGMA) was employed as a primary anchoring layer to attach the polymer chains to the surface of a silicon wafer. A linear temperature gradient heated stage was used for the generation of a gradual variation in the thickness of the anchoring PGMA film along the substrate. The obtained gradient was translated into the polymerization initiator gradient via the reaction between the epoxy groups of PGMA and the carboxyl functionality of 2-bromo-2-methylpropionic acid (BPA). The attachment of BPA to the surface modified with the monolayer of PGMA was confirmed by X-ray photoelectron spectroscopy experiments. To complete the experimental procedures, surface-initiated atom transfer radical polymerization was performed to synthesize the grafted polymer layers with thickness and surface densities that were varied along the substrate. The grafting density of the samples created in this three-step process ranged from 0.75 ± 0.05 to 1.5 ± 0.25 chains/nm2. It was estimated, from a comparison of the surface densities of the initiator and the attached polymer that the efficiency of the initiation from the surface was on the order of 5−10% and was dependent upon the surface concentration of the initiator and the time of polymerization.

“Grafting From” Technique

In the grafting from technique the polymerization is intiated from the substrate surface by attached intiating groups.it is employed when high density grafting needed. Polymer brushes grown by this method possess high density of attached chain. Fine tuning of polymer layer is possible. 

The technique employed for the synthesis of the grafted layers using the PGMA approach was polymerization initiated from the substrate surface by attached initiating groups. In this grafting process monomer molecules penetrate through the already grafted polymer layer easily and significant grafted amounts can be reached. This technique has been used for the preparation of thick grafted layers of high grafting density on the surface. We used the PGMA layer to attach an initiator for Atom Transfer Radical Polymerization (ATRP) and conducted grafting of polymers initiated from the surface to synthesize layers possessing a high grafting density. Bromoacetic acid (BAA) was used as an initiator of the ATRP polymerization. BAA was attached to the PGMA layer from gas phase through the reaction between carboxylic and epoxy functionalities. The deposition was performed at different temperatures (300C – 1100C). In one of the grafting experiments, the surface of PET film was modified with PGMA/BAA layer and ATRP of styrene initiated from the PET surface was carried out. As a result of the polymerization, a PS layer was firmly grafted to the PET surface. Figure 3 shows SPM images and values of water contact angles for virgin PET surface, PET surface covered with PGMA/BAA combination, and grafted PS layer. One can see that the surface morphology and wettability of the PET film was changed after the polymerization. The obtained result suggested applicability of the developed synthetic approach to surface modification of fibers and textile materials.

“Grafting To” Technique

In grafting to technique, end functionalized polymer molecules react with complementary functional groups located on the surface to form tethered chains.the density of the brush obtained by the grafting to method can be increased if the macromolecule attachment is conducted from a solution or from melt. Melt method has advantage over solution method.

An additional increase in grafting density can be achieved from PGMA anchoring layer. Polymers possessing different functional groups: carboxy, anhydride, amino and hydroxy were grafted to the surface modified with PGMA anchoring layer from melt. Hydrophobic and hydrophilic homopolymers, statistical and block copolymers were firmly attached to the surface. For instance, hydrophilic (poly (ethylene glycol, PEG)) and hydrophobic (polystyrene, PS) polymers were attached to PET, polyethylene and polysiloxane surfaces. Figures 1a and 1b show morphology and wettability of PET surface modified with PS and PEG grafted layers. The scanning probe microscopy images revealed that the polymeric surface was completely covered with the grafted layers and the polymer grafted dictated the surface properties of the polymer film. PEG and PS were also successfully grafted to PET fiber and textile materials utilizing the proposed approach.

 The thickness of the grafted layers ranged from 1.5 nm to 20 nm. The thickness of the PGMA film had no decisive influence on the grafting amount for polymers that are immiscible with PGMA. We attached the same grafted layers to relatively thin (1.0 nm) and thick (10 nm) PGMA films. If polymers to be grafted are miscible with PGMA, the grafted amount is strongly dependent on the anchoring layer thickness.

Synthesis and Characterization of Switchable Coatings.

The key characteristic of the “smart” materials is the ability to switch and/or tune the properties by applying external stimuli. An example of this type of smart material is a binary (hybrid) polymer grafted layer composed of two immiscible polymers, grafted to a substrate. Due to the phase segregation the morphology of the mixed polymer nanolayers is sensitive to the surrounding medium. Hybrid layers can be switched between different surface energetic states upon exposure to different temperatures, selective solvents, or other physical stimuli. For instance, the interaction of the binary polymer layer with a selective solvent will cause a change of the surface properties of the polymer film, since one of the two polymers preferentially occupies the surface layer. We report here on the surface morphologies and wettability of polymer coatings prepared from hybrid polymer layers of varying composition of grafted chains of polystyrene (PS) and poly(2-vinylpyridine) (PVP). The layers were synthesized by grafting of the polymers to epoxy modified surface. The wettability measurements clearly showed that a top layer of the binary brush switched from hydrophobic to a hydrophilic energetic state, upon exposure to selective solvents toluene and ethanol, respectively. When we exposed the sample to toluene, PS preferentially occupied the top of the layer, while after ethanol treatment the surface properties were dominated by PVP .Scanning Probe Microscopy also confirmed the switching effect. The morphology of the surface differs upon exposure to different solvents.

We also synthesized switchable nanolayers by combination of the grafting of end-functionalized polymers (“grafting to”) and polymerization initiated from the surface (“grafting from”). The combination allows synthesis of responsive nanolayers consisting of polymers that can only be attached by the certain grafting method. The synthesis was conducted according to the following procedure. Halogen carboxylic acid (HCA), bromoacetic acid (BAA) was used as an initiator of ATRP polymerization. Attachment of the BAA molecules to the surface covered with the PGMA film was conducted from gaseous phase. The reaction between the epoxy groups and carboxyl functionalities of the halogen acid led to 2-bromoisobutyric esters derivatives of the PGMA (ATRP initiator). Next, the synthesis of the poly (t-butyl acrylate) brush was carried out by the “grafting to” method. The PTBA melt grafting buried the ATRP initiator under the polymer brush with a significant thickness of 12-20 nm. To complete the fabrication of the mixed brush, ATRP of styrene initiated by the PGMA/BAA macroinitiator was carried out. As a result of the developed process, the mixed polymer brushes with when the hybrid layer was exposed to the different environments. PTBA brush thickness 12-20 nm and PS layer 1-100 nm were obtained. Hydrolysis of PTBA to polyacrylic acid (PAA) was utilized to synthesize polymer layers possessing hydrophobic/hydrophilic properties. The brushes changed their surface morphology, when they were exposed to solvent with different polarity (Figure 6). For the best samples contact angle was changed by 400

We have developed several approaches to fabrication of the stimuli-sensitive fibers by “one-pot” techniques, where all components of the smart nanolayers are simultaneously deposited on the surface and attached in one single step. For example, we studied the one-step synthesis of PS-PVP hybrid nanolayers. The end-functionalized PS and PVP were deposited onto the surface (modified with PGMA) simultaneously from joint solution. An initial study of the effect of depositing varying amounts of polymers indicated a preferential grafting of PVP at higher deposited amounts of polymer blend. However, the composition of the grafted nanolayer could be regulated by the ratio of the polymers in solution. Rinsing the mixed PS/PVP polymer brush in selective solvents allowed observation of the change in water contact angle as a function of the nanolayer composition.

Using toluene and ethanol as the selective solvents the hydrophilic/hydrophobic nature of the brush-air interface changes was probed. In toluene PS dominates the interface with larger contact angle values. Conversely, ethanol results in a PVP dominated surface and lower contact angle values. We also observed (by scanning probe microscopy) changes in the roughness and structure of the nanolayer surface corresponding to the solvent treatment and the layer composition. The phase imagery indicated a degree of segregation between the PS and PVP rich phases.

Switchable Unary Polymer Brush

 It was shown above that the epoxy groups located in the loops/tails of the adsorbed PGMA macromolecule are accessible to the functional groups of an end-functionalized polymer. The mobility of the loops/tails of PGMA could be also effectively used to develop a novel system, which is robust, and possess wettability on demand. The proposed unary polymer brush (UPB) system benefited from the mobility of the PGMA loops effectively to switch surface properties. UPB can be described as a binary system consisting of an end-functionalized polymer grafted to a macromolecular anchoring layer. The developed UPB system consists of end grafted PS and PGMA anchoring layer. It was anticipated that the mobile loops/trains of the macromolecule can be effectively used to tailor surface properties Using PGMA as an anchoring interlayer we have synthesized a switchable polymer nanolayer on the surface of PET textile material. The PET fabric changed the surface properties after being treated with different solvents (Figure 13). When the fabric was exposed to toluene, it became hydrophobic and water did not penetrate through the material. Conversely, water penetrated between favorable state of PS (non-polar) and favorable state for PGMA (relatively more-polar). It is evident from Figure 11 that a surface saturated with PS chains will not switch. The requirement for the UPB system to be effective is to control the grafting density of PS. In the current study the amount of PS grafted was controlled by regulating the amount of PS initially dip coated.

SPM analysis of the substrates covered with UPB after solvent treatment (Figure 12) showed a well-defined change in morphology for higher molecular weight PS. The surface changed from “smooth” (toluene) to “ripple” (MEK) after treatment with selective solvents. The phase segregation can be explained in terms of mobility of the free end of PS and restricted mobility of the “loops” due to the anchored “train” segments. The higher mobility of the PS chains indeed resulted in perpendicular segregation with one of the species enriched at the surface. This layered segregation resulted in the “smooth” morphology after toluene treatment. While after MEK treatment, the restricted mobility of “loops” prevented layer segregation of PGMA at the surface. This resulted in the two species to self-assemble laterally into well-defined two dimensional structures corresponding to the “ripple” morphology. Contact angle measurements after solvent treatments indicated that the highest molecular weight PS (Mn= 672,000 g/mol) showed maximum switching (approx. 200). Throughout the textile materials, if it was exposed to MEK. The wettability changes were reversible. 

The PGMA platform was also used to attach an initiator for ATRP to the specific areas on the surface and conducted grafting of polymers initiated from the substrate. The nanolayers possessing high grafting density while only covering a fraction of the surface were synthesized. The developed process has been utilized for the synthesis of the hybrid nanolayers with phase segregation at different levels. Fig demonstrates nanolayers-precursors synthesized by ATRP for the formation of dense hybrid films possessing dispersed and co-continuous morphology

               Conclusion

Grafting techniques that allow attachment of different polymers to the surface of fibers and fabrics were developed using the PGMA platform. Switchable polymer coatings were fabricated on model substrate by attachment of two immiscible polymers to the substrate surface. Then, an adaptive nanolayer was synthesized on the surface of PET textile material using the developed grafting approach. The surface properties of the PET fabric changed after being treated with different solvents. The properties of the brushes can be controlled by polymer nature, structural and morphological factors. 

[textilegfg]

CARDING THEORIES

CARDING THEORIES

By

Miss Vijeyata Lolge and Miss Rashmi Shrivas

CARDING ACTION

The carding action is basically a separation process of fibre tufts between two interacting wire covered surfaces.  The necessary condition for carding is

1.  .   There should be two wire covered surfaces facing each other

2.    Distance between the interacting surfaces at their closest approach should be around 0.3 mm

3.    Wires of both the interacting surface should be inclined & their direction should be opposite to each other

4.    Surface should move either in same or opposite direction, if they move in they move in the same direction the surface charged with material should move at the faster speed.

The fibre can only move downwards along the wire point provided towards the base which is the product of tension acting on fibre tuft being pulled by two wire points& the coefficient of friction between wire point & fibre.

THEORIES OF CARDING

Classical theory

According to this theory, a fibre can be carded between two oppositely inclined wire points covered surfaces moving with a high relative speed, provided the wire are so inclined that the sliding component of tension acting in the fibre is strong enough to move the fibre down the wire towards its base. This is fulfilled only when

cot α>µ

Where,

α= inclination of wire point

µ= coefficient of friction between the fibre & wire.

The classical theory does not take into account the centrifugal force & presence of air current due to rotating elements and it is argued that the carding force which slides fibre down the wire is so small in comparison to compression & centrifugal force that it has practically no effect on the filling of the clothing.

Strangs theory

This theory is based on Prandtls Boundarylayer theory. In a card, cylinder may be considered to be enclosed from all sides by flats, back & front plates, licker in, doffer and undercasing, rotates in medium of still air. According to boundary layer theory, a series of concentric layers of air of infinitesimal thickness surround the cylinder. As a, these layers also rotate along with the cylinder with different velocities. The velocity of the layer in contact with the cylinder surface will be equal to the cylinder. The velocities of each successive layers become less & less as its distance from the cylinder surface increases until a layer close to the base of flat wires is reached where the velocity is low. The presence of surrounding air current has been confirmed by Kamogawa, Kanda & Imami, Krylov. Because air has such a different velocities, within the space between flats & cylinder. When a tuft is introduced in this boundary layer, it is subjected to terrific force caused by the shearing action of air. The air shear force on a tuft can be given by following equation.

F = RVA/d

Where,

R= coefficient of viscosity of air at given temperature (poise)

V= velocity of air current (m/s)

A= projected area of tuft in the

d= depth of air boundary layer (m)

The depth of boundary layer appears to be the distance between of wire on cylinder & flats. The force therefore increases as the setting between flats & cylinder reduced. It is this shear force that separate the fibre tufts into individual fibres. The reason of fibre transfer from licker in to cylinder has been assigned to the boundary layer of licker in & cylinder. The air stream around cylinder having higher velocity removes fibre from licker in around which air stream revolves at lower velocity. A theory explaining carding action solely by boundary layer and shearing force of air current is unrealistic since carding has found to occur even at very speeds. However, air current which is definitely present due to rotating cylindrical element may have some role in carding.

Kaufmans Theory

Tufts held on cylindrical surface approach to cylinder flat zone at very high speed and are introduced into the narrow gap between the flats &cylinder wire points, which is generally much lesser in dimension than size of tufts. The resulting compression force, the fibres into the wire clothing of both flats & cylinder since the flats are practically stationary as compared to fast moving cylinder surface, the loading factor of compression force against the flat is greater than that against cylinder which is due its movement present larger surface area for the same compression force. According to Kaufman’s calculation, the compression force against cylinder acts on 6 time larger surface as compared to flat surface. The penetration of teeth into the tuft immediately followed by shearing action on tuft due to great difference in speed between flat & cylinder. As a result, the tuft is pulled apart into pieces. The process repeats itself when a part of tuft is held by cylinder approach the subsequent flats and this goes on. As a result, the size of tuft diminishes progressively. Generally, the opening and separation processis over by the time, the tuft goes to 5th& 6th flat location. As a result of carding action, the flat gets loaded with fibre & the cylinder is evenly covered by separated fibres. The drawing apart of fibre between the two surfaces may also be considered as the process of interaction of friction field created between the fibres and wire points of cylinder & between fibre and wire points of flat place one above the other. 

[textilegfg]

Knitting Machine

A machine used to make knitted fabrics or garments. A knitting machine forms loops of yarn and connects them into various knits.

Knitting machines differ in purpose, design, and type of knitting needles. All knitting machines may be classified according to the number of knitting needles per unit length of the needle cylinder. The most widely accepted system uses the English inch (1 inch = 25.4 mm) to measure the length of the needle cylinder. Machines produced in the USSR range in gauge from 3 to 36. The higher the gauge, the finer the fabric produced. For example, 34-gauge machines are used for knitting fine stockings; here, the gauge corresponds to the spacing of the needles 0.75 mm apart in the needle cylinder.

The principal working parts of a knitting machine are the looper, the yarn feed motion, and the take-up motion. The looper contains the needle cylinder with the needles, sinkers, a presser (for spring needles), yarn guides, and other elements. The sinkers, blades with complex shapes, bend the yarn into loops and move the yarn along the shaft of the needle (if the needles are stationary) or hold it (if the needles are moving); one sinker is usually positioned in each space between the needles. The presser, in the form of a wedge, plate, or disk, presses on the needle hook and prevents the loops from falling into the hook.

When the yarn is laid on the needles, the yarn feed motion maintains a specific and constant tension, with the aid of the yarn guides, brakes, take-up motions, and other attachments. In some yarn feed motions, the length of yarn is measured off for each loop row. The yarn may be fed in individual strands (in weft-type machines) or in groups (in warp-type machines). The take-up motion draws the finished knitwear off the needle cylinders while maintaining a constant tension. The material may be drawn off by means of tension created by the weight of the take-up motion or a separate weight, or it may be accomplished by means of rollers.

The knitting processes are automated by mechanisms that control the consistency of feed and yarn tension and the proper working order of the needles; they also rectify any defects that may appear, such as running loops. In full-fashioned machines, various special mechanisms transfer the loops when the width of the cloth is altered, form separate loop rows, introduce reinforcing yarn, alter the density of the knit, and form complex, three-dimensional shapes in such articles as hosiery and gloves. Electronic control devices have been developed for selecting or introducing the needles in knitting patterned and open-work weaves. In knitting artificial fur, circular knitting machines are used that have miniature carding devices in each loop-forming system; these devices knit the tufts of long fibers into loops to form a nap.

The productivity of knitting machines, in million loops per min, ranges to 3.74 for warp-type machines, 5.94 for circular knitting machines, and 1.44 for automatic circular hosiery knitting machines. Knitting machines manufactured in the Federal Republic of Germany, the USA, Great Britain, Czechoslovakia, and the German Democratic Republic are widely used. The further development of knitting machines is aimed at increasing the gauges available, increasing the number of loop-forming systems, and automating the knitting process.

In addition to industrial knitting machines, home hand-knitting machines and devices are also produced. The primary assemblies in hand machines are the loop-forming elements (latch needles and sinkers), carriage, and row counter. The carriage controls the action of the needles and the sinkers; it is moved by hand along guide tracks. The knitting devices have pull-out hooks, a rack with pins, on which the loops are manually hung, and straightedges, by which the hooks are moved and the tightness of the knit is adjusted.

[textilegfg]

Survey of Blow Room Practices by Pierce-Kelly & Coleman

Survey of Blow Room Practices by Pierce-Kelly & Coleman

Abstracts

Trials were taken in 40 mills; where 100 lbs of cotton passed through Blow Room & Carding.Waste collected separately at every machine & fractionated as – Lint, Chaff (The scales or bracts borne on the receptacle among the small individual flowers of many plants), Dirt & Dust. Survey covers comprehensively different combinations of Blow Room and types of cottons. An assessment of Blow Room is based on (1) Cleaning Efficiency and (2) Good Lint in waste.

Survey of Blow Room Practices

Cleanliness was judged by comparing trash content of the product with that of stock fed. Also, these ratios for different stages were expressed in “Logarithmic Form”.The cleanliness of the stock was measured by the logarithms of trash content at that stage (Trash being calculated by fractionation at subsequent stages in the operation).This quantity is expressed as ‘G’ (Weight Grade) and is found to bear close relationship with American grades.The drop of the value of G between any stages is taken as a measure of ‘cleanliness’ achieved during the ‘operation. This drop in the value is denoted as ‘g’ and helps in assessing the performance of individual machine. In the same manner, Wastage of good lint incurred, in the same manner, is expressed in logarithmic value – Lint Deficiency – ‘D’. This was calculated from the yield of ‘good lint’, obtained from the stock fed at each stage. Thus, ‘G’ represents the actual cleanliness and ‘D’ the actual wastage at any particular stage; whereas the values ‘g’ (change in G) and ‘ℓ’ (change in D) show the successive changes. In conclusion, it was shown that, when values of ‘g’ and ‘ℓ’ are roughly equal, the action of the machine (or process) may be considered “Normal”.  On the scales adopted, the equality of ‘g’ & ‘ℓ’ means, in fact, that the relative elimination of trash effected by the machine is relative to 100 times the relative loss of lint. By plotting the value of ‘g’ against ‘ℓ’, it is possible to detect any abnormal behavior. Such graphs demonstrate that flocked cotton is responsible for a disproportionate lint loss and that sandy cotton gives abnormal values of ‘g’. Sometimes a low value of ‘g’ is associated with still a lower value of ‘ℓ’. This suggests that air currents are ‘unusually’ strong; however, they favor the recovery of ‘good lint’.

Introduction & Summary

In this general survey, there was found to be random and incalculable variation in the action of the machines. It was also found that the droppings contained both useful lint and unwanted trash.

Cleaning Action & Lint Loss:

The actual weight of the trash in the droppings can’t be taken as measure of its cleaning power. This is because, it obviously depends upon the trash content in the ‘fed’ material (& also on the positioning of the machine in the sequence). That is why a ratio of trash ‘eliminated’ to that ‘fed’, being a better measure, was taken in the study.However, if this were merely taken as the cleaning power of the machine, then again, it would be highly misleading. This is because, then mere removal of the stock in the form of trash would indicate as ‘Cleaning’. Comparing therefore, the trash in delivered material to that fed would be far more ‘sound’. Again, this ratio can’t be taken as ‘Quantitative’ measure of the cleaning action because; the trash content in the feed material (stock-fed) is not proportional to the ratio itself.

The two cleaning actions may reasonably be regarded as equal, if they lower the ‘trash content’ in equal ratio. If the two cleaning actions occur in ‘succession’, it is expected the combined action would lower the trash content by the ‘square’ of the ratio of single action. In such a case, the measure of action being ‘twice’ that of single action, the Logarithms are taken for this purpose. Direct measurement of the trash was not taken; instead, the droppings collected plus the waste in sliver (or lap) was assumed to be the ‘Total Waste %’ in cotton. (Possibly no Shirley m/c available then)

The dust concentration shows a strong correlation with the original trash content in sliver.‘Cleanliness’ of the stock is measured by the log of trash content in the material. The drop in the value of this ‘G’ between any two points is taken as measure of cleaning action of the intermediate process (as mentioned – this value is ‘g’).The yield of Lint in the stock from 100 lbs of bale cotton is also expressed by logarithm. But, to avoid negative values and decimals, this is slightly changed and called as ‘Lint Deficiency’ – “D”. Waste of Lint (Lint Loss ‘ℓ’) is measured by increase in the value of ‘D’. ‘D’ is the ratio of Wt. of cotton processed to Wt of the clean lint present. Lint being lost in the waste, proportion of lint in the stock delivered reduces; hence value of ‘D’ increases

Description of the Test & their Results:

40 tests each of 100 lbs are employed and proceed up to card. The droppings at every machine were separately collected & weighed. They were fractionated into – lint, seeds, chaff, dirt & dust. Fractions are considerable (in large quantity) and only their weights are amenable (responsible) to general statistical survey.

Description of the Test & their Results:

However, the weights do not fully describe the fractions.  Hence, some supplementary tests like ‘lint loss’, microscopic examination of trash fraction and dust count of card room air were taken. ‘Stapled tests’ (diagram of lint in the droppings) modify the elimination of ‘waste-fullness’ and they reveal that there is more short fibres in the droppings than in the stock.This excess is more marked in licker-in fly. The trash is all useless and harmful. The fractions of trash are – very easily eliminated smooth seeds and mineral dust. The tenacious part consists – bearded motes & light dust, the chaffs of broken leaves and stalk and all these make-up the bulk of the trash.

The trash remaining in the sliver is very small for accurate fractionation. The trash content in the sliver is roughly constant fraction (about 1/10) of that of card strip.In the whole paper, the quantities are expressed as ‘parts’ per 10,000 parts of bale cotton 

Analysis of Action of Opening Machines:

The total cleaning action, involving blow room and licker-in action, till the material reaches the card cylinder varies from g = 303 to g  = 951, with mean value of 557 The degree of cleaning (g) or the proportion of original trash is independent of original weigh grade (G0) or grade of bale cotton. Normally Lint Loss, as measured by ‘ℓ’ is roughly equal numerically to the ‘cleaning’ (as measured by ‘g’). In proportional scale, the proportional loss of ‘trash’, is 100 times that of lint.

Cleaning Power

The number & the power of machine also vary, but it is not associated with variation in cleaning. Thus, an easily cleaned cotton is given milder treatment and vice-versa.

On average g = ℓ = 557

Licker-in is twice as long as ‘Crighten’; five times as 3 B.B. and 22 times Exhaust Opener. (Comparatively)

In this case, both ‘g’ and ‘ℓ’ are taken as the measure of opening treatment that the cotton receives in the machines. However, ‘g’ is to be preferred (reasons given later).The treatment given to the cotton in the previous machine is very important in judging the action of any machine.Thus, Porcupine opener fed by the lattice (practically unopened stock) shows more powerful action than the one placed in Scutcher where cotton is far more open. Though the causes for the difference in the power can’t be determined with certainty, the speeds of the beater and the weight of the feed appear to be influential. Flocked cotton is responsible for abnormally high lint loss & sandy cottons for high cleaning.

In some cases, it was found that with low ‘ℓ’ and low ‘g’, strong air currents helped some selective recovery of lint owing to buoyancy. The most striking conclusion was that the present machinery failed generally and consistently to perform such an action of detachment of trash; and the trash, in turn, was carried forward. Thus, there was some definite carry-over of loose trash-&-lint to the subsequent machine (“Re-combination of Lint & Trash”). The action of Dust Trunk following Crighten is an example. The great bulk of trash is vegetable originated and remains substantially constant throughout the process.Sand drops early in the process; seeds are selectively eliminated by scutcher; leaf fragments and bearded motes persist preferentially through all the openers while little dirt enters the ‘dirt boxes’.

No direct relation could be established between ‘lint loss’ and measurable characters of cotton fibres, the influence of the latter being overshadowed by complex variations with varying effects. The variations in the readings of trash and lint for the same machine in different mills are due to variation in setting, load (feeding) and air currents of the machines & their adaptation to cotton; the great difference of the kind & behavior of trash - which may be sand or fuzzy motes – and in the product – which may be fluffy or partially rolled into flocks or strings.

Staple Length of Lint Fraction:

It appears that there is little change in the staple from bale cotton to sliver, if any; there is slight decrease in the length. This is because, all the waste in the lint is much shorter in staple. Therefore, the fibres either carried away in air exhaust or included in trash fraction are predominantly short. It is also evident that if there is fibre breakage, it is probably in the card. The lint in the flat strip is much longer than the one from scutcher droppings. Similarly, lint in scutcher dropping is longer than that in crighten dropping, though the difference is not large & all these are useful in waste spinning.

Staple of Lint & Invisible Loss

Licker-in fly is of different nature and has little spinning value on the whole, the lint fraction may be taken as loss of some useful cotton. This results in loss of sliver quantity, though its quality remains almost unchanged.

Invisible Loss:

Out of 10,000 parts 9379 parts are recovered as ‘finisher lap’; whereas 428 parts are collected as ‘droppings’, thus leaving 193 parts as unaccounted ‘Invisible Loss’.This consists of moisture, lint and dust, all of which escape through air exhaust. A small insignificant amount is lost in handling & collection. 

Scale of Cleanliness

The diminution in the trash content decides the cleaning action of the machine. However, the reduction from 10% to 9% can’t be regarded the same as the one from 2% to 1%Therefore, the ratio is the way of comparing. Thus, the reduction from 10% to 5% would be the same as the one from 2% to 1%. The data of lint & trash recovered from 100 lbs of bale cotton are converted into two quantities better suited to general comparison and analysis.The trash content is multiplied by 100 and its logarithm is taken. The value is then multiplied by 1000 to express ‘G’. This is done to avoid negative values and decimals.

Similarly, the ratio of weight of the bale cotton to weight of the lint present is initially found out. It is expressed in logarithm. It is then multiplied by 100,000 to expressed ‘D’As the value of ‘G’ defines the dirtiness of the stock, higher value would indicate dirtier cotton. Further, a given decrease in this value would also indicate, by the same proportion, drop in the trash content. The value of ‘D’ (waste incurred) increases as the pure lint decreases, thus meaning that the Lint Deficiency or extent to which the lint falls short of the full weight of the bale cotton. During the progress of a test, the value of ‘G’ drops, as the trash content of the product is successive stages reduces; whereas the value of ‘D’ rises. Change in ‘D’ is Lint Loss.

The decrease of ‘G’ on passing through a machine is the measure of cleaning done and is denoted by ‘g’.The value of ‘D’ increases (as yield of pure lint from the stock at subsequent stages in comparison to full weight of the bale cotton fed decreases). This is because the material is lost in the form of waste and the proportion of lint in the stock delivered, therefore reduces.‘D is the ratio of ---- (Weight of Bale cotton processed) divided by ---- (Weight of clean lint present).As the denominator is reduced (lint is lost through waste extracion), the ratio (‘D’) increases.

American Grades of Cotton

MF1, SGM2, GM3, SM3, SM4, M5, SLM6, LM7, SGO8 & GO9

Relation between ‘G’ and grades is as follows:

N + 1 = 8 [G/1000 - 2)

With G = 3000, then N = 7 (As per above LM – Low Middling)

Analysis – Cleaning action & Lint Loss

Total action of Blow Room & Licker-in:

The total cleaning varies from G = 303 to 951. In this case the average value is G = 557. The lowest and the highest values of the cotton occur on the same and average grade. Thus, there is no correlation between cleaning & trash content (R = 0.177).The total cleaning may therefore, be regarded as ‘high’ or ‘low’ by comparing it with the value 557, irrespective of the grade of cotton. It shows that the normal practice doesn’t compensate for low grade by extra cleaning i.e. by removing extra proportion of trash

Effect of Grade on Lint Loss:

There is a marked correlation with grade. The dirtier cotton, on the average, loses more lint [R between ‘G0’ & ‘ℓ’ = 0.607].  Independently of the grade, there is also marked tendency for Intense Cleaning associated with ‘High Lint Loss’. (R between ‘g’ & ‘ℓ’ = 0.451]. The correlation of Lint Loss with the grade arises mainly from a group of large lint values, in tests; where two major Openers were used – Willow & Crighten, Two Crighten or Crighten & Buckley (Horizontal) Opener.

Such treatment is given for hard-pressed (difficult to open) cotton.

Analysis – Cleaning action & Lint Loss

This is because, the harder bales and the harder treatment, when they go together, have a tendency to flock the cotton. However, this must be distinguished from a systematic tendency for high trash content to cause extra lint loss.

Cleaning & Lint Loss:

If the flocked cottons are kept aside as abnormal, the grade seems to cease, to be of importance in determining the normal ‘Lint Loss’. Then it (grade) evidently shows closer relation with the cleaning. The majority of the cases show a ‘total cleaning loss’ within 100 units. The larger excesses are due to heavy losses in Licker-in region.The small lint losses may be explained by conservative cleaning of trash which is removed easily.Amount of Treatment: The lowest (g = 303) and the highest (g = 951), both follow the relation g = ℓ, reasonably well. They occur in the same weight grade of cotton. The cleaning and the lint loss, to be normally expected in a Blow Room, depend on the ‘combination’ of the machines actually used.Ratio of lint loss (‘ℓ’) to Cleaning (‘g’) in Machines): The average ratio of g / ℓ is 1.33 and remains more or less the same in Blow Room & Card (Licker-in).If the cotton contains much heavy mineral dirt, a large proportion of this is likely to fall out at the first opportunity without corresponding lint loss. The normal value of g / ℓ is independent of machines or its position in the sequence.

Normal Behavior:

The ratio of g / ℓ is calculated for all the opening machines, except Hopper, Dust Trunk and Exhaust Opener. Licker-in however is included. The large majority of the test show this value is as less than 1.35; medium value is 1.1 and lower one is 0.8. Though the Licker-in has 24 times the action of Exhaust Opener, it does not sieve or select the particles.These beaters only detach these particles under their beating & opening treatment according to own power of adhesion of these particles. The ‘normal’ relation as g = ℓ means that the average probability of a trash particle detaching itself from the stock processed, during an opening process, is 100 times that of ‘Lint’.

Measurement of Action of Machine - (Choice of ‘g’):

Considering the nature of action, essentially these machines are openers; they beat the cotton into small tufts and from the opened part or surface of separation, the dirt or loose lint may fall through the grid into dirt box. This may only occur at the opened part.It is conceivable therefore, that dirt and lint can’t be separated from the center-unopened lumps of cotton.Hence, the cleaning action is essentially the result of opening action & both, the amount of cleaning ’and‘ lint losses may be regarded as a measure of it. On this view and in the light of the results of the above sections, ‘g’ and ‘ℓ’ are equivalent measures of cleaning and opening action of the machine. Also, they are satisfactory measures as they are independent of grade of cotton fed. Both ‘g’ & ‘ℓ’ are subject to rather length-based error.

The former (g) may be exaggerated by the presence of sand or latter (ℓ) by the flocked cotton, both of which again fall-out with abnormal cases. The detached particles of the lint may be selectively recovered by an upward air currents (as in scutcher). If this principle is deliberately exploited and stabilized, the value of ‘ℓ’ would cease to be a valid measure of opening treatment. As the exaggeration of ‘g’ by sand is almost limited to first opener, and if serious, may be discounted. Thus, this quantity (‘g’) may be taken as the most valid measure of opening & cleaning treatment presently available.

M/c                 g            ℓ               M/c                 g             ℓ

Licker-in            225        303            P.B.                 40           23

Crighten            113        133            P.F.                 66           61

Buckley             100        127            Murray O.        55          37

Willow                75         179            Ex. O.              10           14

3 B.B.                 45          58            Dust Trunk       24           34

2 B.B.                 42          81            Hopper F/O       5           12

                   K.B.                    31           61

[Higher ‘g’ → Higher Cleaning; Higher ‘ℓ’ → Higher Lint Loss]

Action affected by Previous Treatment of Cotton:

This depends upon the value of ‘G’ of the stock fed. Thus, a Porcupine Opener may be much effective in the beginning than the porcupine at the scutcher. Similarly, Buckley at the beginning is much more effective than one that follows Crighten.

Action according to Type of Machine:

The standard of judging the action is to determine the average value of cleaning and lint loss.In Blow Room, the Crighten shows the highest value of ‘g’ (113). Buckley has subnormal efficiency. Kirschner Beater is rather less efficient than other beaters. The large lint loss (‘ℓ’) in K.B. and 2 B.B. is due to flocked cotton (possibly due sheet feed) present at the earlier stage.Thus, both K.B. and 2 B.B. are not responsible for this loss. The low lint loss in P.B. is common to other machines.Though P. Feeder shows higher ‘g’ value, this must be discounted by its position, being at scutcher.Murray Opener has similar effect, considering its position after Crighten.

The small beater at the beginning of Exhaust Opener, which merely acts without nipping a grip is seen to be very ineffective. Its dirt box acts rather as an extension of dust trunk. The dust trunks themselves appear to be effective; but it is not due to their own action. It is merely because they allow dropping of trash and freely drawing the lint through the previous opener by strong draught that is necessitated by the trunk themselves. Hoppers have little action. At the beginning of combination, the droppings are light unless they include lumps. However, the hopper following the opener gives more droppings, which are particles detached but not dropped in the previous machine.

Action of Individual Machine:

To seek the cause of variation, the account must be taken of the position of the machine. The P.O. of the lattice feeder is usually in the beginning and its action is greatly affected by the character of cotton and trash. By the time the scutcher are reached, the variation in the type of trash is much reduced. The scutcher is particularly suited for generation and control of air currents, nicely adjusted to carry the lint while allowing the deposition of trash. This requires effective adjustments of fan speeds, beater speeds, grid bar settings, rate of feed and character of cotton.Mere increase of air currents is likely to carry away both the cotton and the trash through ongoing stream.

When considering the action of any machine followed by a Cage, where cleaning is also done, the credit must be given to the action of the beater preceding it. For, a Cage can only extract particles that have already been detached. The cleaning action of the Crighten is very sensitive to the cotton processed. Here the heavy lint loss is mainly due to flocked cotton; even then sometimes the adjustments of the surrounding bars might prove to be economical. Buckley has normal cleaning power.Dust trunks vary in their action. They offer a further opportunity for the deposition of particles liberated by the beater and carried forward by the air currents. The droppings greatly vary due to bends in the pipes & strength of air currents.

The beater at the beginning of exhaust opener attempts to hit the loose cotton, not held in the nip, nor restrained in any way; but seems merely to spread it on its way.In the sequence of P.O. → C.O. → Dust Trunk → Ex.O, the cotton goes continuously without re-condensation and much loose trash and lint can accompany the cotton in the strong air currents.The droppings are also affected by the efficiency of collection – by the grids, dust box, air currents and by the carry-over from the preceding machine.

Average % of Trash (composition)

M/c                 Seed             Chaff              Dirt            Dust

P.O.                  21                 54                  21               3

C.O.                  20                 57                 18                5

Dust Trunk        21                 53                 19                7

Ex. O.                21                 54                 19                6

3 B.B.                30                 52                 15                3

2 B.B.                24                 60                 14                2

Bale                  18                  59                 13              10

Taker-in            12                  69                 15               4

Cotton Character:

A short coarse hair should cling less and should fall more readily. It is evidently seen that short fly in the droppings was abundant. A high value of lint loss is from short coarse cotton, which also happens to belong to low grade. But high lint loss is definitely due to hard tufts of cotton produced by – mechanical action, balling or flocking.Flocks can’t be regarded as the effect of – either the cotton character or its grade. The association is accidental & due to commercial cause. Coarse cotton is cheap and great care in ensuring itsCleanliness is not justified. It also commonly packed very densely. To reduce the transport cost. This obviously requires drastic treatment in its opening - & hence flocking.Therefore, the drastic opening will flock or string fine cottons of low or high grade. The fact appears to be that, the difference, either in clinging power or floatability between the coarse and fine lint, is small compared with difference between either kinds of lint and trash or densely tufts of cotton (Principle used in Air Stream Cleaner)