Significance Of Optical Brighteners In The Paper Industry
Optical brighteners are additives that paper manufacturers use to help make paper appear "whiter." They are also referred to as Optical Brightening Agents (OBA). To make paper appear brighter, it is a common practice for paper manufacturers to add various chemicals to it. These chemicals can take invisible UV light and re-emit in the blue spectrum at a point that is just barely visible to the naked eye. While our eyes see this as a brighter, blue-ish white, it is only with the help of light measuring instruments that you can discern whether it is a different shade of blue. This is the reason why printer profiles made with paper that uses a good amount of optical brighteners prints out yellow tint images. The profile tries to rectify for what it sees as too much blue in the paper.
Finding Presence Of OBA In Paper
The most effective way to see the presence of OBA in paper is to shine a black light on it. A black light lamp will cause the OBA to glow. This effect can be seen with white clothing under a black light. Paper (or clothes) without artificial brighteners will not react to the black light at all. The very popular invisible ink pen probably works because it it equipped with a black light lamp that illuminates the OBA in the invisible ink.
Consider this blog and hire a color consultant to get assistance in color integration, dye and OBA selection and best color practices development.