Colorants for Stable Colors in CP Soap

When making Cold Process (CP) soap, the high alkaline environment can cause some colorants to change or shift color. This is especially true for some synthetic dyes like Acid Dyes or FD&C Dyes, which are often not stable at high pH.

Colorants that are generally stable in the high alkaline conditions of CP soap and maintain their color well are typically Mineral Pigments. These include:

• Iron Oxides: Very stable in alkali. Available in various shades like Red Iron Oxide, Yellow Iron Oxide, Black Iron Oxide. Mixing them can create brown shades.
• Ultramarines: Provide blue, pink, and purple colors and are also alkali stable.
• Chromium Oxide Green: Gives a green color and is alkali stable.
• Micas: Pearlescent powders available in many colors. Some are stable in CP soap, but it's important to check the stability information for each specific mica color before use.

For the orange and red colors you are looking for, we recommend using Red Iron Oxide and Yellow Iron Oxide. Mixing them will give you orange, and using Red Iron Oxide alone will give you red. These colors are highly stable in CP soap.

It is always recommended to test the colorant in a small batch before using it in your main CP soap recipe to ensure it performs as expected and the color remains stable.