Answer to your questions about Permanent Hair Cream

Regarding your questions about Permanent Hair Cream:

1. Adjusting color to natural black and dark brown: The Permanent Hair Cream products available are color bases designed for mixing with a developer and other primary colors to achieve desired tones. However, specific formulas or instructions for adjusting the color base to achieve natural black or dark brown shades are complex and require specialized knowledge of hair colorants and formulation chemistry. This information is not available in the product descriptions.

2. Shelf life after mixing with Developer Solution 9%: The product descriptions for Permanent Hair Cream state the mixing ratio with a developer is 1:1.5. The instructions say to mix the color base with the developer, stir well, and apply immediately. This indicates that the mixture is intended for immediate use after preparation and should not be stored for a long time after mixing. The product descriptions provide storage information for the unmixed product (shelf life at least 2 years when stored properly), but they do not specify the shelf life of the cream after it has been mixed with the developer.

Therefore, it is recommended to mix the Permanent Hair Cream with the Developer Solution 9% just before you intend to use it, following the recommended ratio of 1:1.5.