Color & Pigment Selection for Bath Bombs & Soap, and Glycerin Base Inquiry

Question

I would like to inquire about the following: What type of color should be used in bath bombs? If I want to purchase it here, what is the product name? Which type of [url=https://www.myskinrecipes.com/shop/search?search_query=titanium+dioxide&orderby=position&orderway=desc:1w518xgu]Titanium Dioxide[/url:1w518xgu] should be used with oil soap? What is its name? I want the soap to be completely black. I have used black mica color before, but the result was not black. Can I use carbon powder instead? What is the name of the product that will not cause the soap texture to be grainy and will result in a deep black color? Do you sell clear and opaque [url=http://www.myskinrecipes.com/shop/%E0%B8%AA%E0%B9%88%E0%B8%A7%E0%B8%99%E0%B8%9B%E0%B8%A3%E0%B8%B0%E0%B8%81%E0%B8%AD%E0%B8%9A%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B8%AA%E0%B8%B3%E0%B8%AD%E0%B8%B2%E0%B8%87%E0%B8%84%E0%B9%8C/143-glycerin-%E0%B8%81%E0%B8%A5%E0%B8%B5%E0%B9%80%E0%B8%8B%E0%B8%AD%E0%B8%A3%E0%B8%B5%E0%B9%88%E0%B8%99.html:1w518xgu]glycerin[/url:1w518xgu] bases? I couldn't find them.

MySkinRecipes Expert · Accepted Answer

Answers to Your Formulation Questions

Here are the answers to your questions regarding colors for bath bombs, titanium dioxide for oil soap, achieving deep black color in soap, and glycerin soap bases:

1. Colors for Bath Bombs

For bath bombs, water-soluble colors are generally recommended as they disperse well in water and are less likely to stain the tub. Based on the available products, you can consider the EasyWash™ series of water-soluble colors. These are designed to be easily washed off and are resistant to fading. Examples include:

Brilliant Blue‎ (CI42090) EasyWash™
Acid Violet 17 EasyWash™
D&C Blue No.2 (Indigo Carmine) EasyWash™
Caramel Color EasyWash™
Black Color EasyWash™

These colors can be mixed into the water phase of your bath bomb formulation.

2. Titanium Dioxide for Oil-Based Soap

When using Titanium Dioxide in oil-based soap, you need a type that can disperse well in oil or silicone to avoid white speckling. Based on the product descriptions, the following types are suitable for dispersion in oil or silicone:

Titanium Dioxide Nanosil: This type is specifically mentioned as mixing well in silicone or oil.
SI01-2-TIO2 CR50: This is also described as being dispersible in oil.

These options should help you achieve an even white color or lighten other colors in your oil-based soap.

3. Achieving Deep Black Color in Soap

If mica black did not give you a deep black color, using Carbon Black is a viable alternative for achieving a true, deep black. To avoid speckling in your soap (especially oil-based soap), proper dispersion is key. You can use:

Carbon Black (Nano): This powder has a very small particle size (23-25nm) which helps with dispersion. The description recommends blending it into the formula's surfactant or emulsifier first until smooth before adding to the main recipe. It disperses well in emulsifiers with high HLB.
Iron Oxides Black (Triethoxycaprylylsilane Coated): This is an oil-dispersible black iron oxide powder coated with Triethoxycaprylylsilane, which helps it disperse easily in oil and silicone. This coating can help prevent clumping and speckling.

Choose the one that best fits your soap making process and ensure thorough dispersion before incorporating it into your main soap batch.

4. Glycerin Soap Bases

Based on the search results, clear and opaque glycerin soap bases were not found among the listed products. However, Glycerin (USP/Food Grade) is available. Glycerin itself is a humectant and emollient commonly used in cosmetics, including soap making, but it is not a pre-made soap base.