Dishwashing Liquid Color Fading in Sunlight: Seeking UV-Resistant, Body-Safe Colorants

For your dishwashing liquid, we understand the challenge of color fading when exposed to sunlight, especially since you are currently using food-grade colorants. We recommend considering synthetic cosmetic-grade colorants, which often offer better light stability while still being safe for products that come into contact with skin.

For a lemon yellow color with good UV resistance, we suggest:

• D&C Yellow No.10 (CI47005) (Water-Soluble): This colorant is specifically noted for its good UV resistance and does not fade easily when exposed to light. It is a highly concentrated primary color, safe and licensed for use in cosmetics under USA (FD&C) and Europe (E-Code Cosmetic Color) standards.

For an apple green color, you can consider:

• FD&C Green 3 (Fast Green FCF, CI 42053): This is a synthetic dye approved for use in cosmetics and food, offering a bright green or turquoise hue. It is regulated by the FDA and EU Cosmetics Regulation, ensuring its safety for cosmetic applications.
• D&C Green No.5 (CI 61570) EasyWash™: This is a water-soluble green colorant that is resistant to fading.

To further enhance the color stability of your dishwashing liquid, especially when displayed in open, sun-exposed areas, we highly recommend incorporating a UV filter into your formulation. Products like ActiveProtec™ UV can help protect the color from UV light, which is a primary cause of fading.

While natural colorants like Turmeric Extract Curcumin Yellow Color are available and safe for food, they generally do not offer the same level of light stability as synthetic dyes, which aligns with the fading issue you are currently experiencing.

You can find links to all mentioned products below this answer.