Final answer:
The technique using demi-permanent or semi-permanent hair color to refresh and add shine is called hair glossing. Unlike permanent hair color which chemically alters the structure of the hair, hair glossing adds color and shine without lightening the hair and is less damaging.
Step-by-step explanation:
The technique that uses demi-permanent or semi-permanent hair color to refresh color and/or add shine is known as hair glossing. This process involves applying a colored gloss or glaze that enriches the hair's existing color or imparts a new shade, while also delivering a reflective shine. The usage of hair colors is diverse, ranging from covering grey hair, adopting a trendy color, or restoring the natural hair color that has faded due to hairdressing activities or sun exposure.
Semi-permanent color, which washes out after several weeks, is often used in hair glossing, providing a way to experiment with color with less commitment than permanent hair dye. It's important to note that semi-permanent hair color cannot lighten the hair, and it might not cover grey or white hair completely. In contrast, a permanent hair color changes the hair's structure chemically and lasts until the colored hair is cut off, even though the color can fade over time due to washing.
Another hair treatment often confused with coloring techniques is perming, which refers to chemically altering the hair to create curls or waves, resulting in a style that can last several months. Perms are not used to alter the color of hair, but rather to change its texture and shape.