Thickening Sulfate Free Shampoo Base

Regarding your question about thickening the Sulfate Free Shampoo Base:

Yes, the "thickness" mentioned in the product description refers to viscosity.

The Sulfate Free Shampoo Base is designed to be easily thickened. You have a few options:

• Using Salt: You can use pure table salt (sodium chloride) at a concentration of approximately 0.5-1.5%. The base description notes that adding salt requires the formula to contain an amphoteric surfactant like Coco Betaine, and the thickening may take up to 24 hours after mixing.
• Using Alternative Thickeners: If salt doesn't provide sufficient thickness or is not preferred, other recommended thickeners include:
  • SugarThick™ (PEG-120 Methyl Glucose Dioleate): This is derived from sugar and is effective for thickening various detergents, including this shampoo base. It can also help reduce irritation from harsh surfactants. You found this works well in your testing.
  • EasyThick™ (POLYOXYETHYLENE GLYCERYL ISOSTEARATE): This is another easy-to-use liquid thickener specifically for shampoos and liquid soaps, providing a clear texture.
  • Hydroxypropyl Methylcellulose (HPMC): This forms a non-ionic gel and is suitable for formulas containing electrolytes. Various grades are available, offering different viscosity levels.

You observed that your initial formula did not thicken significantly, but replacing the fragrance with SugarThick did. While all ingredients can potentially affect viscosity, a fragrance at 1% is generally unlikely to cause a significant reduction in viscosity unless it contains specific components that interfere with the thickening mechanism of the base. The success you had with SugarThick confirms that the base can be thickened and that SugarThick is an effective option for your formula.

If the base does not thicken sufficiently on its own after 1-2 days as sometimes expected, adding one of the recommended thickeners is the correct approach to achieve your desired viscosity.