Liquid Oil Soap Formula for Dry Skin

It's great that you're exploring making liquid oil soap! It can be a wonderful option for dry skin. Let's look at your formula and questions.

Formula Adjustment

Your proposed formula uses 45% Oil Soap™ and 55% oils and glycerin. To achieve medium to relatively high cleansing, medium to high moisture, and avoid sliminess, while also ensuring stability, we can adjust the formula slightly.

Based on the guidance that a higher percentage of Oil Soap™ (around 60-65%) is recommended for stability when using diverse or heavy oils, and considering your desired cleansing level, a suggested adjusted formula is:

• Oil Soap™: 60%
• Fractionated Coconut Oil: 15%
• Extra Virgin Olive Oil: 7%
• Rice Bran Oil: 4%
• Sunflower Oil: 4%
• Castor Oil: 4%
• Glycerin: 6%

This adjustment increases the Oil Soap™ percentage for better cleansing and stability, while maintaining a significant portion of nourishing oils and glycerin to provide medium to high moisture without excessive sliminess.

Role of Oils in Oil Soap™ Formulas

Unlike traditional cold process bar soap where different oils significantly impact properties like hardness, cleansing, and foam, in a liquid oil soap made with Oil Soap™, the oils primarily function to condition and nourish the skin. They do not significantly affect the foam characteristics or cleansing power of the soap base itself.

Preservatives in Waterless Formulas

You are correct that a preservative is generally not needed in a formula that contains no water, as microorganisms require water to grow. However, if you are producing this soap for sale or using packaging where water could potentially be introduced (e.g., in a shower environment), it would be prudent to consider adding a small amount of preservative as a precautionary measure to ensure long-term stability and prevent microbial growth.

This adjusted formula should provide a good starting point for a moisturizing liquid oil soap suitable for dry to very dry skin with the cleansing properties you desire.