To cater to anyone’s predilection or necessity, silicone rubber is offered in an array of colors from red to blue to black. There is even a translucent rubber sheet! Commercial manufacturers take advantage of the customizable capabilities of silicone rubber and produce colorful, eye-catching goods such as cell phone cases and baking utensils. Laboratory and food handling industries use white silicone rubber sheets to easily spot contaminants on the material’s surface. Whether it is purely aesthetic or strictly functional, the coloring of silicone is a handy feature of this elastomer.

In its uncured state, silicone rubber is a highly-adhesive gel or liquid. In order to convert to a solid, it must be cured, vulcanized, or catalyzed. This is normally carried out in a two-stage process at the point of manufacture into the desired shape, and then in a prolonged post-cure process.

A common way of coloring silicone is to apply a pigment paste when the silicone sheet is on a roll mill. At this point of the manufacturing process, the rubber has not yet been cured. The paste can be blended into the material fairly easily by simply applying the paste with a paint scraper or similar instrument. When using pigment paste, virtually any color of silicone can be produced.

Normally, pigment pastes are used for commercial products and not industrial parts. There is no justifiable use for a pink gasket! Yet it’s common to see parts such as gaskets and seals made from colored material like red silicone sheets. This is because there are certain additives that inherently color the elastomer. For example, heat stabilizer additives are especially known to affect the shade of silicone, often resulting in a red, black or white silicone rubber sheet.

As previously mentioned, translucent rubber sheet is easily achieved since it is generally produced in this form naturally. No other rubbers can achieve the same translucency as silicone. This stands out as one of silicone’s defining characteristics. This ability is an invaluable feature for medical devices that require the properties of rubber with a degree of visibility through the material. This is just one of many functions of a colored silicone sheet!