Improving Grey Hair Darkening Shampoo Color

Question

I am making a grey hair darkening shampoo with the following main ingredients: Coco Glucoside 15%, Coco Betaine 20%, SemiColor - Wood Black 0.5%, ColorFix 0.6%, Silicone Hi-Cond 2%. I am satisfied with the viscosity from Sugarthrick and foaming from Flora Foam. The issue is that after washing my hair 6 times, it doesn't seem dark enough. I would like to know if there are any ingredients I need to add to improve the color result.

MySkinRecipes Expert · Accepted Answer

Improving Grey Hair Darkening Shampoo Color

Based on the ingredients you are using for your grey hair darkening shampoo, specifically SemiColor - Wood Black and ColorFix, here is some information and suggestions to help improve the color result:

SemiColor - Wood Black is a semi-permanent hair color designed to gradually build color with repeated use. The product description highlights a few key points for optimal performance in a shampoo formula:

Surfactant Compatibility: SemiColor - Wood Black is cationic and works best with non-ionic or amphoteric surfactants. Your use of Coco Glucoside (non-ionic) and Coco Betaine (amphoteric) is appropriate and should not interfere with the color.
Importance of pH: The description strongly suggests that color adherence is improved in a more alkaline formula, recommending a pH of approximately 9. If your current shampoo pH is lower (typical shampoos are around pH 5.5-6.5), this could be a primary reason for the color not depositing effectively.
Salt/Electrolyte Sensitivity: High levels of salt or electrolytes in the formula can affect the longevity of the color. Ensure other ingredients added for viscosity or other properties are not introducing excessive salts.
ColorFix Usage: You are using ColorFix at the recommended rate of 0.6% for shampoo, which is correct for helping the color adhere.

Recommendations to Improve Color Darkening:

Adjust the pH: This is the most crucial step based on the product information. Check the pH of your final shampoo formulation. If it is below 8.0, gradually adjust it upwards towards pH 9 using an alkaline agent like Triethanolamine or a Sodium Hydroxide solution. Do not exceed pH 9, as the color can degrade. Adjusting the pH will help open the hair cuticle slightly, allowing the color molecules to penetrate and adhere better.
Consider SemiColor Concentration (with caution): You are currently using SemiColor - Wood Black at 0.5%. The product description recommends 0.2% to avoid staining, but the usage range is up to 1.0%. While increasing the concentration slightly (e.g., to 0.7% or 0.8%) might deposit more color, be aware that this increases the risk of staining your scalp, skin, or towels. Test a higher concentration on a small area first.
Ensure Proper Dissolution: The SemiColor - Wood Black powder should be mixed in water heated to 70-80°C to ensure it is fully dissolved before adding to the rest of your formulation.

By adjusting the pH of your shampoo to around 9, you should see a significant improvement in how well the SemiColor - Wood Black adheres to your hair, leading to a more noticeable darkening effect over multiple washes.