Plastic coloring products are influenced by many factors will fade. Plastic coloring products fade and pigments, light fastness of dye, the oxygen resistance, heat resistance, acid-proof alkaline, and the properties of resin used. Should be used according to the plastic products processing conditions and requirements, at the required during the production of masterbatch pigments, dyes, surfactants, dispersants, the performance of carrier resin and anti aging agent can be used only after comprehensive assessment.
Color masterbatch for pigment first preprocessing, high tinting strength, dosage is lower and the quality is stable, transportation, storage, easy to use, greatly reduce the environmental pollution.
Dispersant on the surface of a pigment wetting, penetration to exclude air, scatter agglomerations, aggregate into tiny, stable and uniform particles, and are no longer together, in the machining process commonly used dispersant for low molecular weight polyethylene wax, for difficult to disperse organic pigments and carbon black by EVA wax or oxidized polyethylene wax, synthetic low molecular weight polyethylene and polyethylene wax cracking the legal system of low molecular weight polyethylene wax have very big difference.
Other additives with coupling agent, antioxidant and light stabilizer, antistatic agent, filler, etc., depending on the requirements and variety addition amount, known as multi-functional masterbatch, or join brightener, beneficial to molding products stripping and improving the products surface brightness.
Performance of the color masterbatch have off color, white, yellow, yellowing, thermal stability, oxygen index, melt flow rate, etc., of course the fineness of pigment, mobility, chemical resistance, toxicity is related to the performance of masterbatch, some indicators in the special use is very important, such as fiber masterbatch filter values (DF) fineness.
1. Light fastness and light fastness of the colorant directly affect the products fade, the glare of outdoor products, the light of colorants used (fast) level requirement is an important index, light level is poor, products in use will soon fade. Weather resistance of products to choose light shall be not less than 6 grade, had better choose 7, 8, interior products optional four, five. Carrier resin light resistance to change the color also has a great influence, its molecular structure before and after the resin caused by exposure to the sun's ultraviolet rays fade changes occur. Join in the masterbatch light stabilizer and so on ultraviolet absorbent, can improve the coloring and shading light resistance of plastic products.
2. The heat resistant pigments thermal stability refers to the processing temperature pigment thermal weightlessness, the degree of discoloration, faded. Inorganic pigment ingredients for metal oxides and salts, good thermal stability, high heat resistance. While organic compound paint under a certain temperature will occur the change of the molecular structure and a small amount of decomposition. Especially PP, PA, PET products, processing temperature above 280 ℃, when picking colorant to pay attention to the heat resistance of paint on one hand, on the one hand, want to consider the heat resistance of paint, usually require heat time is 4-10 rain... .
Of certain metal ions will promote the thermal decomposition of resin, pigments, copper, manganese, iron, cobalt pigments such as ageing effect for promoting the polyolefin, cadmium, calcium, potassium, sodium, such as paint. Same metal elements according to the order of the pure metal, metal oxides, metal salts.
3. The oxidation resistance of some organic pigments in the degradation of macromolecules in the aftermath of the oxidation or other changes, and gradually fade, the process is a process of high temperature oxidation, the second is of strong oxidizer (such as chromium Huang Zhong chromic acid radical) oxidation. Lake, after using azo pigment mixed with chrome yellow, red will gradually subside.
4. The acid and alkaline coloring plastics faded and chemical character of the colorant (acid and alkali resistance, reducing oxide). Such as chromium molybdenum red resistance to dilute acid, but sensitive to alkali, cadmium yellow don't acid, these two pigments and phenolic resin for some colorants have strong reducing effect, the serious influence of colorant heat resistance, weather resistance and fade.