Cream Formulation with Urea and Preservative

Yes, both Urea and a preservative are necessary for a cream formulation. Urea is an excellent ingredient for moisturizing and can also provide exfoliating benefits at higher concentrations. A preservative is crucial in any water-based product to prevent microbial growth and ensure product safety and longevity.

Ingredient Recommendations:

• Urea (High Purity, Cosmetics, Powder): Provides intense hydration and helps with exfoliation. It is recommended to use it at 3-20% for moisturizing (5% for very dry skin) or 10-20% for exfoliating and moisturizing. Note that Urea can cause the pH of the formula to rise over time, especially at temperatures above 35°C. It is highly recommended to stabilize Urea by using Gluconolactone at approximately 15% of the Urea amount to help control the pH in the range of 4-5.5.
• Mild Preserved™ COS: A broad-spectrum, odorless preservative effective in a wide pH range (2-8), suitable for most cosmetic formulations containing water.
• CreamMaker EG™: An easy-to-use emulsifier to create a stable cream.
• Carbomer U21: A thickener that helps create the cream texture and provides stability. It is easy to disperse and works in a wide pH range.
• Glycerin: A humectant that helps draw moisture into the skin.
• LipidSoft™ B: An emollient that provides a pleasant skin feel.
• Triethanolamine 99%: Used to neutralize Carbomer and adjust the final pH of the cream.

Sample Cream Formula (100g):

Phase 1 (Water Phase)

• Water: 67.5 g
• Glycerin: 5 g
• Urea (High Purity, Cosmetics, Powder): 10 g
• Gluconolactone: 1.5 g

Phase 2 (Oil Phase)

• LipidSoft™ B: 5 g
• CreamMaker EG™: 4 g

Phase 3 (Thickening & Preservation)

• Carbomer U21: 0.5 g
• Water: 5 g
• Triethanolamine 99%: 0.5 g (Adjust as needed to reach desired pH)
• Mild Preserved™ COS: 1 g

Instructions:

1. Disperse Carbomer U21 in the 5g of water (Phase 3 water) and let it hydrate completely.
2. Combine ingredients in Phase 1 and heat gently if necessary to dissolve Urea. Stir until clear.
3. Combine ingredients in Phase 2 and heat gently to melt CreamMaker EG™. Stir until clear.
4. Slowly add Phase 2 to Phase 1 while stirring continuously with a mixer until a stable emulsion forms.
5. Add the hydrated Carbomer dispersion (Phase 3 Carbomer + water) to the emulsion and stir well.
6. Add Triethanolamine 99% drop by drop while stirring until the cream thickens and the desired consistency is reached. Check and adjust the pH to be in the range of 4-6.
7. Add Mild Preserved™ COS and stir to ensure it is fully incorporated.
8. Package the cream. It is highly recommended to perform a challenge test on the final product to confirm the effectiveness of the preservative system.