Glycolic Acid Toner Formulation

Creating a toner with 10% Glycolic Acid and 90% Witch Hazel is possible, but there are important considerations for safety and effectiveness, especially for a leave-on product.

Here's a breakdown and suggestions:

Concentration and pH

A 10% concentration of Glycolic Acid is quite high for a leave-on toner for general consumer use. According to the product information for Glycopure™ (Glycolic Acid powder), the recommended maximum for consumers in leave-on products is 5% with a pH of 3.5 or higher. At 10%, the pH will be very low, which can cause significant irritation.

If you choose to proceed with 10% Glycolic Acid, it is highly recommended to:

• Adjust the pH of the final product to be between 3.5 and 4.0. This is crucial for both effectiveness and reducing irritation. You will need a pH meter and a neutralizing agent (like Sodium Hydroxide solution) to do this accurately.
• Consider using it as a wash-off treatment (apply for 10-15 minutes, then rinse off) rather than a leave-on toner, especially if you are new to AHAs or have sensitive skin.
• Start by using it infrequently (e.g., once or twice a week) and gradually increase frequency as your skin tolerates it.

Your proposed formula of 90% Witch Hazel and 10% Glycolic Acid powder adds up to 100%, leaving no room for other beneficial ingredients.

Adding Moisturizing and Soothing Ingredients

To help counteract the potential irritation from Glycolic Acid and provide hydration, it is highly beneficial to include moisturizing and soothing ingredients.

Based on the search results, good options include:

• Allantoin: Known for its soothing and anti-irritant properties, and it helps promote tissue regeneration. It was also suggested in the previous reply. A typical usage rate is 0.1-2.0%, but solubility in water at room temperature is limited (around 0.5%). You might need to heat the water phase slightly to dissolve it or use a small amount of a solubilizer like Glycerin.
• Glycerin: A humectant that attracts and retains moisture in the skin, helping to hydrate and reduce dryness that can be associated with AHA use. It can be used at various concentrations, typically 1-10% in toners. Glycerin also helps dissolve Allantoin.

Proposed Formulation Approach

Instead of a simple 90% Witch Hazel / 10% Glycolic Acid mix, consider a formula that includes soothing and moisturizing components and allows for pH adjustment.

Here is a conceptual example (percentages are illustrative and need to be adjusted based on desired feel and final pH):

• Witch Hazel (Distillate - Alcohol Free, Paraben Free): 75-85%
• Glycopure™ (Glycolic Acid 100% Powder): 10% (Note: Requires pH adjustment to 3.5-4.0 for leave-on use)
• Glycerin (USP/Food Grade): 3-5%
• Allantoin: 0.2-0.5% (Ensure it dissolves fully)
• Distilled Water: As needed (to dissolve Glycolic Acid and Allantoin, and bring total to 100%)
• pH Adjuster: Sodium Hydroxide solution (to raise pH to 3.5-4.0)

Alternatively, you could use Witch Hazel (Alcohol Free, Paraben Free) Plus Allantoin as your base, which already contains Witch Hazel and Allantoin, simplifying the process. Then you would add the Glycolic Acid powder and adjust the pH.

Steps:

1. Dissolve the Glycolic Acid powder in a small amount of distilled water.
2. Dissolve Allantoin in the water/Glycolic Acid solution (gentle heating may be needed, ensure it cools before adding Witch Hazel). Or, dissolve Allantoin in the Glycerin first, then add to the water phase.
3. Combine the Glycolic Acid/Allantoin/Water mixture with the Witch Hazel and Glycerin.
4. Mix thoroughly.
5. Measure the pH. It will likely be very low.
6. Slowly add a dilute Sodium Hydroxide solution, mixing well after each addition, until the pH is between 3.5 and 4.0.
7. Package the toner.

Remember to always perform a patch test before applying the product to your entire face.