Which product is utilized to equalize porosity and replace missing pigment?

Filler is the product specifically utilized to equalize porosity and replace missing pigment in the hair. When hair is subjected to chemical processes, such as bleaching or dyeing, it can become uneven in its porosity, meaning some areas may absorb color more than others. This can result in an uneven color application.

Using a filler helps to restore this balance by adding back some of the missing color and effectively filling in gaps in the hair structure, allowing for a more uniform color result. Fillers can come in different forms that either add warmth or cool tones, preparing the hair for subsequent color applications.

In contrast, intensifiers are designed to enhance or boost specific shades in hair color but do not function to address porosity issues. Metallic dyes contain metal salts and can create buildup and unpredictable results, so they don't serve the purpose of equalization. Permanent hair color provides lasting effects but assumes that the hair has been prepped adequately for even application, which would not address porosity imbalances on its own. Thus, the use of a filler is crucial in situations where the hair's porosity needs to be equalized for optimal color results.