According to data and practice, there are many factors […]
According to data and practice, there are many factors that affect the fading of plastic products. The fading of plastic colored products is related to the light resistance, oxygen resistance, heat resistance, acid and alkali resistance, and the characteristics of the resin used. In the production of color masterbatch, the required pigments, dyes, surfactants, dispersants, carrier resins and anti-aging additives can be selected after comprehensive evaluation of the above properties. The following are the conventional reasons for product discoloration and logistics performance , For your reference.
The light fastness of the colorant directly affects the fading of the product. For outdoor products exposed to strong light, the light fastness (light fastness) level requirement of the colorant used is an important indicator. The light fastness level is poor, and the product will fade quickly during use. So this is why, for example, anti-glare boards on highways, water horses, etc., after a few years of use, the color will become lighter after exposure to the sun, but generally when blow molding, a certain amount of anti-UV ingredients are added to ensure Persistence of product color retention time.
2. Heat resistance
The thermal stability of a pigment refers to the degree of thermal weight loss, discoloration, and fading of the pigment at the processing temperature. Inorganic pigments are composed of metal oxides and salts, with good thermal stability and high heat resistance. The pigments of organic compounds will undergo molecular structure changes and a small amount of decomposition at a certain temperature. In fact, we need in the production process. If it is a plastic product that requires high temperature heating, we need to choose a pigment with more heat resistance to ensure the color change and fade, and the overall appearance of the product.
Some organic pigments undergo macromolecular degradation or other changes after oxidation and gradually fade. This process is high temperature oxidation during processing, and oxidation when encountering strong oxidants (such as chromate in chrome yellow). After the lake, azo pigment and chrome yellow are used in combination, the red color will gradually fade.
4. Acid and alkali resistance
The fading of colored plastic products is related to the chemical resistance of the colorant (acid and alkali resistance, oxidation-reduction resistance). For example, molybdenum chrome red is resistant to dilute acid, but is sensitive to alkalis, and cadmium yellow is not acid resistant. These two pigments and phenolic resins have a strong reducing effect on certain colorants, which seriously affect the heat resistance and weather resistance of the colorants and cause fading.More about:rattan storage box