* Varying Pigment Levels: Dark brown hair has more pigment (melanin) than light brown hair.
* Bleach Impact: Bleach works by breaking down and dissolving the melanin in your hair.
* Uneven Lift: The bleach will lift the light brown hair faster than the dark brown hair because there is less pigment to break down. This means the light brown sections will become lighter shades of blonde or yellow more quickly, while the dark brown sections might still be orange or reddish.
Expected Outcome:
* Light Brown Sections: Likely to lift to lighter shades of blonde/yellow, possibly even reaching pale yellow if processed long enough.
* Dark Brown Sections: Likely to lift to orange, reddish-orange, or reddish-brown shades. It will likely take multiple bleaching sessions to lift to a blonde shade.
* Overall: A patchy, uneven result with different tones and colors throughout your hair. You'll likely see bands of color and variations in shade.
Important Considerations:
* Hair Damage: Bleaching is damaging to hair. Uneven bleaching can lead to uneven porosity, which makes hair more susceptible to breakage and dryness.
* Toning: After bleaching, you'll likely need to tone your hair to neutralize unwanted warm tones (orange, yellow). However, toning unevenly bleached hair can be tricky and may not completely fix the patchiness.
* Professional Advice: If you have hair with multiple shades, it's best to consult a professional colorist. They can assess your hair's condition, formulate a plan to achieve your desired color while minimizing damage, and use techniques like color correction to even out the tone.
* Strand Test: Before bleaching all of your hair, always do a strand test. This will give you an idea of how your hair will react to the bleach and how long you'll need to process it.
In summary, bleaching hair with varying shades of brown will likely result in an uneven, patchy color. It's best to consult a professional or proceed with caution and be prepared to address the unevenness.