* Color Theory: Brown is made up of primary colors, including red and yellow. If you put brown over pink, the red in the pink will likely influence the brown, leading to a muddy, reddish-brown result. The pink might also show through, depending on how dark the brown is and how intense the pink is.
* Pre-Lightening (Bleaching): Pink hair dye often requires pre-lightening your hair to a light blonde or pale base. If your hair is pre-lightened, putting a dark color directly over it can lead to unpredictable results. The underlying lightness can make the dark color fade faster or look less true to tone.
What to Do Instead:
1. Color Correction/Neutralization:
* Green: Green is opposite red on the color wheel. Pink hair contains red pigment. Using a green-toned color depositing mask or a professional color corrector with green undertones can help neutralize the pink before applying brown. *Be cautious:* Overdoing it can turn your hair muddy.
* Ashy Toner: An ashy (cool-toned) toner can also help to neutralize some of the pink tones.
2. Fill the Hair:
* Orange/Red Filler: Because you're going from a light (pink) to a darker (brown) shade, you'll need to "fill" the hair with the underlying pigments that are missing to ensure the brown adheres properly and doesn't fade to a muddy color. Using an orange or reddish-orange filler will replace the warm tones that were lifted during bleaching/lightening.
3. Choose the Right Brown:
* Cool-Toned Brown: Select a cool-toned brown dye (ash brown, for example) to help counteract any remaining pink or red tones in your hair. Avoid warm-toned browns (golden brown, auburn brown) as they will likely enhance any reddishness.
* Darker Brown: Going for a darker brown will increase the chances of covering the pink, but it might not be necessary if you've properly neutralized and filled.
4. Strand Test: *Always* do a strand test before applying the dye to your entire head. This will give you a preview of the final color and allow you to adjust the process if necessary.
5. Professional Help: If you're unsure or dealing with a complex color situation, it's always best to consult a professional hairstylist. They can assess your hair and recommend the best course of action to achieve the desired brown color without damaging your hair.
In summary, you'll likely need to neutralize the pink and fill your hair with underlying pigments before applying a cool-toned brown for the best and most predictable results.