FAQ of optical brighteners

Reasons for yellowing of PVC panel board and the solution!

What is a PVC panel board?

PVC panel board is a common decoration material, often used in kitchens and bathrooms, and other places. PVC panel board has a good moisture resistance. It will not absorb excess moisture in the air and produce mold and corrosion even if used in a humid environment. PVC panel board is more economical and easy to installation than stainless steel sheet and aluminum panel board.

PVC panel boards

With the popularity of PVC panel boards in the market, consumers demand a higher quality board. However, many manufacturers often encounter the situation of yellowing of the PVC panel board, today we will learn about the reasons for yellowing and the solution.

01 Production reasons

In the process of production, PVC resin needs to be heated and screw and barrel shear action. If the barrel temperature is too high, the host machine speed is fast, which will lead to the yellow of the PVC resins.

Solution

1, The temperature of the barrel can be reduced appropriately to solve the yellowing situation.

2, Reduce the host machine speed, improve the feeding ratio. Make sure the materials are mixed evenly to avoid yellowing.

3, Restart the machine. Improper start usually leads to yellowing products.

02 Resin reason

PVC resin is very sensitive to heat, and PVC resin is the main raw material of PVC panel board. When the heating temperature reaches above 90℃, a slight thermal decomposition reaction will occur. And when the temperature rises to 120 ℃ decomposition reaction will intensify. At about 150 ℃, after 10 minutes, the PVC resin will gradually change from white to yellow-red-brown-black.

03 The additives reason

This situation is mostly due to the replacement of additives.

Solutions

1、Increase the content of the stabilizer.

2、Adjust the balance of internal and external lubricants.

3、Add the fluorescent whitening agent to solve the yellowing.

4、Add UV absorbers to increase the anti-aging effect.

Shandong Grand Chemical Co., Ltd. is a manufacturer specializing in fluorescent whitening agents, the company has developed a special fluorescent whitening agent product for PVC panel boards, the dosage is only about two to 100-300gram per ton. If you have any problems in whitening for PVC panel board, please do not hesitate to contact us any time!