In the plastic industry, especially in the plastic recycling industry, the whiteness of plastic products or recycled plastic products has always been an important factor affecting the value of the plastic products.After a long time extrusion, coupled with the sun, the appearance of the waste plastic always very dark, white plastic yellowing. Even recycled products look old, so to make the appearance of recycled plastic white, in addition to the selection of plastic raw materials, but also need to add recycled plastic fluorescent whitening agent.
The plastic raw material itself has a great influence on the whitening effect of recycled plastics. In addition, various plastic additives also play an important role.
(1)The colour of the plastic itself, many of which have different colours, such as the brown colour of the Phenol formaldehyde resin itself. The color of plastic itself is an important basis for the design of plastic coloring formula, only colorless plastic can be prepared in a variety of different colors.
(2) The transparency of plastics. Only transparent plastic can be made of transparent, translucent or opaque colored plastic.
(3) The colour of the plastic. In order to eliminate yellow light, blue colorant and fluorescent brightener such as ultramarine blue are often added to eliminate the influence of yellow light and improve the whiteness of plastic products.
(4) Light resistance of plastics. For plastics with better light resistance, the formula can be considered based on its original color. For plastics with poor light resistance, when considering the formula, the difference in light resistance must be considered to obtain good results.
(5) The influence of various additives in plastics. In order to obtain good material properties or unique functions, various plastic additives are often added, such as various filler masterbatches, special masterbatches, molding processing modifiers, optical brighteners, anti-wear agents, antioxidants, and anti-ultraviolet agents, Infrared absorbers, etc., these will also affect the coloring effect.
At present, among the chemical auxiliary plastic additives used in the recycled plastics industry, optical brighteners are indispensable. Generally, plastic manufacturers will choose optical brighteners with low price, good quality, good light resistance, high temperature resistance, and good migration resistance. Ogilvy Chemical provides fluorescent whitening agents OB OB-1 FP-127 KCB KSN KSB and blue pigments such as Ultramarine Blue, Phthalocyanine Blue for plastic whitening, factory direct sales, fast delivery, free samples, customized whitening solutions.