Color Fading in Water-Based Cream with Oil Phase
Question
I have formulated a water-based cream that also contains an oil phase. The cream has a pH of 5-5.5. I am facing an issue where the color of the cream fades when exposed to sunlight. What could be the cause, and how can I prevent this color fading?
Answer
Solution for Color Fading in Cream
It appears the color fading in your water-based cream with an oil phase, exposed to sunlight, is likely due to the colorant not being sufficiently stable to light or the formula's conditions (pH 5-5.5). Water-soluble dyes, while easy to use in water bases, can sometimes be prone to fading, especially when exposed to light or in formulas containing an oil phase where they may not be fully compatible or stable.
As suggested, the best approach to address this is to use pigments or colorants that are designed to be stable in formulations containing an oil phase. These types of colorants, such as color lakes dispersed in oil, offer better light stability and are more compatible with the oil components in your cream, leading to more consistent and long-lasting color.
Consider using oil-based color dispersions like ReadyMix™ FD&C Yellow No.5 Lake (Oil Based) or ReadyMix™ D&C Red No.7 Lake (Oil Based). These products are pigments pre-dispersed in an oil base, making them easy to incorporate into formulations containing an oil phase without needing extensive grinding or homogenization. They provide stable color that is less likely to fade upon light exposure compared to some water-soluble dyes.
By switching to an appropriate oil-soluble pigment or oil-dispersed colorant, you can significantly improve the color stability of your cream and prevent fading issues when the product is exposed to sunlight.
