Simple Facial Cleansing Gel Formula

Based on the formula you referenced and your goal to create a simple facial cleansing gel for home use, here are the answers to your questions:

1. Substituting Sulfate Free Shampoo Base

Yes, you can substitute the Sulfate Free Shampoo Base (pH 7, Clear, Foaming) with the Sulfate Free No-Tear Shampoo Base (pH 6, Clear, Foaming). Both are sulfate-free cleansing bases suitable for gentle formulations.

The main difference is that the Sulfate Free No-Tear Shampoo Base is specifically designed to be extra gentle and non-irritating to the eyes ("no-tear"). This characteristic is beneficial for a facial cleanser, as the skin on the face is more delicate than the scalp, and contact with eyes is common during washing.

The description for the Sulfate Free No-Tear Shampoo Base indicates its pH is in the range of 6.5-7.5, similar to the regular Sulfate Free Shampoo Base. While the "no-tear" version offers increased gentleness, its cleaning efficiency might be slightly lower compared to the regular version.

For a facial cleanser, the increased gentleness of the Sulfate Free No-Tear Shampoo Base is generally preferred.

2. Adding Citric Acid to Adjust pH

Yes, it is highly recommended to adjust the pH of the formula for use as a facial cleanser. The ideal pH for facial skin is slightly acidic, typically between 5.0 and 6.5. This range helps maintain the skin's natural barrier function.

Both the Sulfate Free Shampoo Base and the Sulfate Free No-Tear Shampoo Base have a pH range of 6.5-7.5, which is slightly higher than ideal for facial skin. Using Citric Acid is a common way to lower the pH in cosmetic formulations.

To adjust the pH, add Citric Acid gradually in very small amounts (e.g., start with 0.1% or less) to the formula after all other ingredients are mixed and dissolved. Stir well until the Citric Acid is completely dissolved, then measure the pH using a pH meter or pH strips. Repeat this process, adding tiny amounts and measuring, until the desired pH of 5.0-6.5 is achieved.

Do not add a large amount of Citric Acid at once, as it can lower the pH very quickly. The exact percentage needed will vary depending on the specific batch of ingredients and the final desired pH, but it will likely be a very small amount.

Revised Simple Facial Cleansing Gel Formula Example:

• Sulfate Free No-Tear Shampoo Base (pH 6, Clear, Foaming): 25%
• Mild Preserved Eco: 1%
• Citric Acid (Anhydrous, Natural): As needed to adjust pH to 5.0-6.5 (start with small amounts, test, and add more gradually)
• Water: Remaining percentage to make 100%

Mix the Sulfate Free No-Tear Shampoo Base and Water first. Add Mild Preserved Eco and stir. Finally, add Citric Acid in very small increments, stirring and measuring the pH until it is in the range of 5.0-6.5.