发布者：唐山天物彩板有限 发布时间：2019-09-27 08:40
If the color coatings are used for too long or not for a long time, they may be aged. Why do we say that long-term construction or storage will be exposed to the sun? It is inevitable that aging will occur through the long-term illumination of light, but we can usually prevent and reduce the speed of aging earlier, so what should we do?
The first necessary condition for the aging or photochemical reaction of the coated plate is that the external components of the coated plate can absorb radiation energy; secondly, when the radiation energy absorbed by molecules is greater than that absorbed by molecular bonds, the coated plate can degrade. Because the shorter the wavelength of light, the higher the energy it contains.
According to the above theory, the aging of coated sheets in atmospheric environment is that the coated molecules absorb the energy of ultraviolet light band higher than their molecular bond energy in sunlight, which leads to the degradation of coated molecules. With the aging of the coating, the substrate body gradually loses, and the coating surface gradually becomes rough and glossy. This loss of the base material eventually leaves relatively stable pigment particles, which remain on the surface of the coating in the form of unbonded powders, a process known as pulverization.
In conclusion, the aging resistance of polyester color coated sheets with different coating thickness is quite different. The aging resistance of thin coated color coated sheets is poor, and that of normal coated sheets is relatively good. Therefore, relying on thinning coating to reduce the production cost of color coated sheet is not feasible, which will inevitably bring serious quality problems. Together, it proves the necessity of clearly specifying the thickness of coating in the order contract of foreign importers of color coated sheet.