Triethanolamine 99% is primarily used in cosmetic and personal care formulations as a pH adjuster, neutralizing agent and formulation aid. The amount required will depend on its purpose in the formulation, the ingredients being neutralized and the desired final pH.
Suggested Usage: 0.1–2%
Higher or lower amounts may be appropriate depending on the formulation. When used specifically for pH adjustment or Carbomer neutralization, Triethanolamine should generally be added q.s. (quantity sufficient) to achieve the desired final pH and viscosity.
Using with Carbomers
Triethanolamine is commonly used to neutralize Carbomer-based thickeners. Carbomers are acidic polymers that generally develop their full thickening ability after neutralization.
First, fully disperse and hydrate the Carbomer in the water phase according to the recommendations for the specific Carbomer grade. Once hydrated, add Triethanolamine gradually with gentle mixing. As the pH increases, the Carbomer structure expands and the formulation will begin to thicken.
As a general formulation guideline, approximately 0.1–1% Triethanolamine may be used depending on the amount and grade of Carbomer present. Rather than adding a predetermined amount all at once, add gradually while monitoring both pH and viscosity, stopping once the desired results have been achieved.
Using with Stearic Acid
Triethanolamine can be used with Stearic Acid in traditional creams, lotions, shaving products and similar emulsions. The two ingredients react to form triethanolamine stearate, which can provide emulsifying properties while contributing body, consistency and cleansing characteristics to the finished product.
For complete neutralization, approximately 0.42 parts Triethanolamine 99% may be required for every 1 part Stearic Acid. In many cosmetic formulations, however, only a portion of the Stearic Acid is neutralized.
For formulations containing approximately 2–5% Stearic Acid, 0.5–2% Triethanolamine is a useful general starting range. The exact amount should be adjusted according to the desired formulation characteristics and final pH.
Using for pH Adjustment
Triethanolamine can also be used to increase the pH of water-based formulations. Add slowly in small increments with good mixing and check the pH between additions. For greater control, particularly in small batches, Triethanolamine can be pre-diluted with distilled or deionized water before being incorporated.
Solubility: Soluble in water
Typical Usage: 0.1–2%
Add To: Water phase or during final pH adjustment
Common Applications: Creams, lotions, gels, serums, cleansers, shampoos, shaving products and other water-based formulations
Formulation Tip: When using Triethanolamine as a neutralizer, always add it gradually rather than adding the full calculated amount at once. The amount required can vary considerably depending on the formulation. Over-neutralization can raise the pH beyond the desired range and, with some Carbomers, may also reduce viscosity. Always check the final pH of the finished formulation.
