It’s frustrating when you color your hair with a semi permanent dye expecting rich, vibrant color all over, only to find that the color barely shows up on your regrowth and roots. There are a few key reasons this happens.
Semi permanent dye only deposits color
Semi permanent hair dye is designed to deposit color onto the hair strand. It does not have the ability to penetrate into the hair cortex and lift or lighten your natural underlying pigment. When you apply semi permanent color to regrowth, it simply coats the strand but can’t get through to the core to cover that underlying pigment.
For gray or white roots in particular, semi permanent dye lacks the peroxide necessary to open up the cuticle and alter the natural pigment. So it ends up depositing only a hint of color rather than complete coverage.
Roots have a tighter, less porous cuticle
Your roots and new growth have a tightly closed, less porous cuticle because this hair has not been subjected to the damage of coloring processes, heat styling, environmental exposure etc. The cuticle near the scalp is at its thickest and healthiest state.
Semi permanent dye works by depositing color molecules into the hair strand. For this to work, the cuticle must be open enough to let the molecules in. If your roots have a tightly shut cuticle, the dye molecules can’t penetrate into the cortex and you get little to no color result.
Previously colored hair is more porous
Hair that has been previously colored, bleached, straightened or subjected to heat styling has a more opened, porous cuticle. The semi permanent dye molecules are able to penetrate into these areas much more easily and deposit rich, vibrant color.
That’s why you often see poor results on the roots but good color uptake through the mid-lengths and ends of hair. The ends will grab the color easily thanks to previous damage making the cuticle more porous.
How to help semi permanent color take to roots
If you want to get better semi permanent color results on regrowth and roots, here are some tips:
- Use 10 volume peroxide as a pre-treatment before coloring. Don’t use higher volumes as this will lift your natural pigment. Peroxide helps swell the cuticle so dye can penetrate better.
- Roughen up your roots slightly with a clarifying shampoo to open the cuticle.
- Apply petroleum jelly/coconut oil to your previously colored mid-lengths and ends. This prevents oversaturation so more dye is forced into the roots instead.
- Leave the color on roots for the maximum processing time.
- Use heat when applying the semi permanent color by putting a warm towel over your head. Heat helps open the cuticle for better dye uptake.
Permanent color for root coverage
While the tips above can help, you’ll generally get the best root coverage with permanent color rather than semi permanent. Permanent hair dye contains peroxide developer which lifts your natural pigment and allows deeper penetration and staining of the cortex.
If you want reliable root coverage every time, switch to an permanent root touch up product matched to your base color. Be aware permanent color involves a higher level of commitment as your roots will need touching up frequently as your hair grows out.
Go darker for better root coverage
If you want to stick with semi permanent dyes only, choose a shade slightly darker than your natural level. While semi permanent color can’t lighten or lift, it can overlay darkness on top better. Just keep in mind this will darken your other previously colored hair too.
Going just a shade darker can help disguise and blend any patchiness at the roots much better. You may not achieve full gray coverage but it will look less obvious.
For example if you have light brown hair, choose a medium brown semi permanent shade. For medium blonde hair, go for a dark blonde. The darker shade has an easier time showing up on resistant grays and regrowth.
Consider permanent root smudge products
There are also some “permanent root smudge” type products available from professional brands like Goldwell, Wella and Schwarzkopf. These are designed to blend and disguise regrowth between permanent root touch ups.
They deposit a sheer veil of permanent color that lightly stains and tones down the roots. While they don’t achieve full coverage, they can help make regrowth less obvious before your next salon visit.
Conclusion
Semi permanent hair dye works best at refreshing your previously colored lengths and ends. For maximum root color and gray coverage, switch to permanent color formulations.
You can also prep your roots properly, choose darker semi permanent shades or utilize permanent root blending products. While you may not achieve perfect root color, these tips can help disguise and minimize the regrowth between permanent root touch ups.
With the right techniques, you can still use semi permanent shades as your main color and tone down roots in between. Just adjust your expectations and accept you may need to blend and disguise regrowth rather than completely cover it until your next permanent salon visit.
| Reason | Explanation |
|---|---|
| Only deposits color | Can’t penetrate and lift natural pigment like permanent color |
| Roots have tight cuticle | Dye can’t pass through into the cortex easily |
| Previously colored hair is porous | Dye uptakes better into damaged, porous areas |
| Tip | How It Helps |
|---|---|
| 10 vol peroxide pre-treatment | Swells cuticle so dye can enter |
| Clarifying shampoo | Roughs up cuticle so it opens |
| Petroleum jelly on lengths | Forces dye into roots instead of lengths |
| Max processing time | Gives more time for dye to penetrate |
| Heat from towel | Helps open cuticle |
