Diluting Cosmetic Color Powder for Storage

Regarding your questions about diluting cosmetic color powder (specifically Yellow Tartrazine CI19140) with water for later use in cosmetic formulations:

1. Using water boiled with Disodium EDTA: Disodium EDTA is primarily used to chelate metal ions in water, which can help improve water quality and formula stability in general. However, boiling water with Disodium EDTA is not a specific requirement for the process of simply diluting this type of color powder. The main concern for storing the diluted color is microbial contamination.

2. Adding Phenoxyethanol preservative: Yes, if you are preparing a diluted solution of the color powder, such as Yellow Tartrazine CI19140, and storing it for later use, it is necessary to add a preservative like Phenoxyethanol. This is crucial to prevent the growth of microorganisms over time, which could spoil the diluted color solution. The recommended usage rate for Phenoxyethanol in this context is typically 0.5-1.0% of the total dilution. If you were to use the diluted color immediately in a cosmetic formula that already contains an effective preservative system, adding preservative to the color dilution itself might not be strictly necessary, but for storage, it is highly recommended.

In summary, while Disodium EDTA is related to water quality, adding a preservative like Phenoxyethanol is essential for maintaining the stability and safety of a pre-diluted color stock solution stored for future use.