Why are transparent silicone rubber products yellow?
Transparent silicone rubber products do not yellowing for a few years, but sometimes in production, some newly baked transparent silicone rubber products look yellow, as if they have changed color. Why do transparent silicone rubber products turn yellow?
I. Vulcanizing agents
1. The properties of vulcanizates can be divided into two types: common type and yellowing resistance.
2. Common type non-yellowing vulcanizate is applied to some non-exposed silica gel products which can be used for darker or less demanding colours.
3. Anti-yellowing vulcanizates are used in products which need to be exposed, light and bright, and require high color requirements.

II. Technological aspects
When transparent silicone rubber products are moulded, the color of transparent silica gel products turns yellow after moulding. The main problems are as follows:
1. Die temperature is too high
2. The curing time is too long.
3. After secondary sulfur addition
3. The quality of raw materials themselves is too poor.

III.Sometimes we add anti-yellowing curing agent to the rubber, but the transparent silica gel products still look yellow after forming. It may be that the anti-yellowing ability of raw materials is too poor. For raw materials with poor anti-yellowing ability, the suggestion is to change the materials directly.
Summary:
Although silicone rubber products have excellent weatherability and aging resistance. But sometimes there are yellow silicone products just out of the oven. In order to avoid this situation, the vulcanizing agent should be selected according to the requirements, the temperature of the mould and the vulcanizing time of the product should be strictly controlled in the process, and the yellowing resistance of the raw materials should be paid attention to in the raw materials.