D&C Red 27 Color Changing Pigment Usage Tips

Regarding your questions about D&C Red 27 Color Changing Pigment not dissolving in water and not changing color immediately when applied from a water mixture, here is some information:

1. Solubility: This pigment is designed to be soluble in oils, not water. The product description recommends using it in anhydrous (water-free) formulations, such as anhydrous gels. This is why you observed that it did not dissolve in water.

2. Color Change Mechanism: The color change of D&C Red 27 is triggered by a change in pH. When the pigment, properly incorporated into a suitable base (like an oil-based or anhydrous formula), comes into contact with the slightly acidic pH of the skin, it undergoes a chemical reaction that causes the color to change, typically to pink.

3. Why it didn't change color immediately from water: Since the pigment does not dissolve or disperse well in water, it cannot effectively react with the skin's pH when applied in a water mixture. The pigment particles are likely just suspended, preventing the necessary contact and reaction for an immediate color change.

Recommendations for Use:

• To use this pigment correctly, dissolve it in a suitable oil or incorporate it into an anhydrous formulation (without water).
• An anhydrous gel base is specifically recommended in the product information.
• The recommended usage rate is typically 0.1-3%, depending on the desired color intensity.

By using an oil-based or anhydrous system, the pigment can properly interact with the skin's pH upon application, allowing the color change to occur as intended.