Tips for Using Laminating Machine
There are two types of laminating machines: instant-coating laminating machines and pre-coating laminating machines. The instant-coating laminating machine has a wide application range, stable and reliable processing performance, and is a widely used laminating machine. Pre-coating type laminating machine, no gluing and drying part, small size, low cost, flexible and convenient operation, not only suitable for laminating processing of large quantities of printed matter, but also suitable for laminating processing of small batches and scattered printed matter such as automated desktop office systems . At present, an advanced pre-coating type laminating machine controlled by a computer has been produced in China.
Pre-coating type laminating machine
The pre-coating type laminating machine has broad application prospects and popularization value, which is the development direction of the laminating machine. However, limited by some conditions such as pre-coated plastic film, the domestic use is still very few.
Instant-coating type laminating machine
The instant-coating laminating machine is a special equipment that coats a roll of plastic film with an adhesive and then dries it. The pressurized composite part is combined with the printed product. There are two types of instant-coating laminating machines: fully automatic and semi-automatic. All types of models are unique in terms of structure and laminating process, but their basic structure and working principle are the same. They are mainly composed of five parts: unwinding, gluing and coating, drying, laminating, and winding, and mechanical transmission. , It is composed of auxiliary devices such as automatic tension control and automatic deviation adjustment for unwinding.
1.Unwinding partThe unwinding operation of plastic film requires that the film always maintain a constant tension. If the tension is too high, it is easy to produce longitudinal wrinkles. On the contrary, it is easy to produce horizontal wrinkles, which is not conducive to the coating of the adhesive and the composite with the printed matter. In order to maintain a proper tension, the unwinding part is generally equipped with a tension control device, such as mechanical friction disc clutch, AC short motor, magnetic powder clutch and so on.
2. Glue coating partAfter unwinding, the film passes through the coating roller and enters the gluing part. Coating forms include: roller reversal type, concave type, direct gluing without scraper, and direct gluing with scraper, etc.
(1) Roller reverse gluingIt belongs to indirect gluing, which is the most used one in each model. The rubber supply roller brings out the glue liquid from the glue storage tank, and the scraper roller and the rubber scraper can scrape the excess glue liquid back to the glue storage tank. The film counter-pressure roller presses the film to be coated onto the surface of the glue roller after homogenization, and maintains a certain contact area. Under the action of pressure and adhesion, the glue is continuously coated on the surface of the film. The amount of glue applied can be changed by adjusting the distance between the squeegee roller and the squeegee roller, and the squeegee roller and the rubber plate.
(2) Recessed gluingIt consists of a metal coating roller with anilox engraved on the surface and a group of film partition rollers. The glue roller is directly immersed in the glue liquid, and the glue liquid is taken out from the glue storage tank with the rotation of the roller, and the excess glue liquid on the surface of the roller is scraped off by the scraper. Under the action of the laminating roller, the glue in the groove of the roller is driven by the directional movement of the film to be coated and spreads evenly on the surface of the film. The amount of glue applied can be controlled by adjusting the grid texture of the surface of the coating roller, the characteristic value of the adhesive, and the pressure value of the laminating roller.
The advantage of gravure coating is that it can more accurately control the amount of glue applied, and the coating is even; but the anilox roll is difficult to process and easy to damage, and needs to be cleaned frequently. In addition, there is a higher requirement for the adhesive when coating.
(3) No-squeegee roller squeeze glue coatingThe glue roller is directly immersed in the glue liquid. During coating, the glue liquid is brought out by the glue roller and the glue is homogenized by the glue roller. The glue is applied by the squeezing force between the film roller and the glue roller. During extrusion, pressure, adhesive performance indicators and coating speed determine the thickness of the glue layer. The amount of glue applied is achieved by adjusting the squeezing force between the glue roller and the glue roller, and the glue roller and the film roller. Therefore, there are higher requirements for the surface accuracy, cylindricity and radial runout tolerance of each roller.
(4) Glue directly with a scraperThe gluing roller is directly immersed in the glue liquid and continuously rotated to drive the glue liquid from the glue tank. After the excess glue liquid is removed by the scraper, it contacts with the surface of the film to complete the glue application.
There is a direct gluing method with a scraper. The design requires the scraper to scrape the glue on the surface of the rubber roller, that is, the straightness of the scraper blade and the surface accuracy of the rubber roller are quite high. The squeegee is generally made of stainless steel belt with high flatness, smoothness and elasticity.
The adhesive coating applied on the surface of the plastic film contains a large amount of solvent and has a certain degree of fluidity. It must be dried before being compounded. The drying part is mostly tunnel type, and the length of the drying tunnel is between 1.5 and 5.5m depending on the model. According to the solvent volatilization mechanism.
Wuxi Coreco has a professional team of highly skilled engineers and mature technology in the design and manufacture of high-performance carbon fiber rollers. Its products are widely used in non-woven fabrics, lithium batteries, conversion, printing and polymer film industries. If you have any demand, welcome your contact.