The yellowing of transparent silicone products is usually caused by issues with the raw material formula used in the production of silicone products. Some newly produced transparent silicone products may appear yellow and have changed color. Why do transparent silicone products turn yellow?
1. The reason for silicone vulcanizing agent
1. The performance of vulcanizing agents can be divided into ordinary type and yellow resistance Its application scope has the following two aspects:
2. Ordinary non yellowing vulcanizing agent, applied to some non exposed silicone products with darker colors or low color requirements
3. Anti yellowing vulcanizing agents are applied to products that require exposure, lighter and brighter colors, and higher color requirements
2. In terms of craftsmanship
The main problems that cause transparent silicone products to turn yellow after molding are:
1. Mold temperature too high
2. The vulcanization time is too long,
3. After secondary sulfur addition
3. The quality of the raw materials themselves is too poor
Sometimes we add anti yellowing vulcanizing agents to the rubber material, but the transparent silicone product still looks yellow after molding, which may be due to the poor anti yellowing ability of the raw material. For raw materials with poor anti yellowing ability, it is recommended to directly replace them.
Although silicone products have excellent weather resistance and aging resistance. But sometimes, freshly baked silicone products still appear yellow. To avoid this situation, it is necessary to choose vulcanizing agents according to requirements. In terms of process, the temperature of the mold and the vulcanization time of the product should be strictly controlled, and attention should be paid to the yellowing resistance of the raw materials.
Due to long-term use, oxygen in the air comes into contact with silicon, producing a pale yellow silica.