Healthline says that if your hair has high porosity, it doesn't hold onto moisture easily, so it has trouble absorbing dyes or other coloring treatments as well. To ensure maximum absorption, use products designed for porous hair before coloring to help the dye penetrate more deeply and stick to each strand.
The Science Behind Hair Color Absorption
If it's too closed or damaged, dye can't penetrate well. Healthy hair with an open cuticle layer will soak up color better, giving you that vibrant look. The pH level and the porosity of your hair also affect how well it takes color.
There are a few reasons the dye isn't taking; 1) It could be that your hair is naturally resistant to bleach 2) the developer may not be strong enough 3) you may not be leaving the dye in long enough. 4) direct dyes usually require hair to be lifted to a level 10 blonde or higher for best results.
pH Levels: The pH level of your hair can influence color absorption. If your hair is too alkaline or too acidic, it may resist color. Hair Health: If your hair is overly damaged or has buildup from products, it may not take color well.
If you have medium or high porous hair, your hair has trouble keeping moisture which, in turn, causes hair color to fade faster. It can't lock-in the dye. If your hair always feels dry, it may be because it's porous. Try adding more hair oils, creams, and conditioning treatments to your hair care routine.
Final answer: Hair that is resistant to color and has a tight cuticle is characterized as having low porosity. Porosity defines the hair's ability to absorb and hold moisture, with low porosity hair being more resistant to chemical treatments.
Gray hair tends to be resistant and typically takes longer to grab hold of the hair. Since there is no pigment, there is no need to lift. You just need to open the cuticle enough to deposit the color. If you feel you can get full coverage using a 10 or 15 volume then by all means use a lower volume.
Our favorite color-depositing conditioner is the dpHue Gloss+ thanks to its wide range of shades, easy application, and ability to soften and hydrate hair. For a clear gloss that adds shine to any hair color, we recommend the Pureology Color Fanatic Top Coat + Sheer.
If you had a bad coloring job your best bet is to visit a reputable beauty salon and have a trained professional perform corrective coloring that will rid you of the unnatural color and give your hair a second chance.
Similar to the orangey issue above, when your regrowth ends up a shade lighter than the rest of your hair, it is typically because virgin hair reacts differently to dye than previously colored strands. The latter is more porous than regrowth and thus quicker to absorb color molecules.
It Can Make Semi-Permanent Hair Dye More Vibrant
Since semi-permanent hair color (and demi-permanent hair color) isn't formulated with peroxide, it can be beneficial to use it on wet hair. This will open up the cuticles of the hair shaft and allow the color to absorb better into wet strands.
The reason people mix hair dye with conditioner is to get a natural-looking, subtle color effect than solid, opaque pigment. It doesn't allow the color to grab your hair too fast and too strongly, as it deposits on the hair shaft without altering hair structure.
Low porosity hair doesn't absorb product
Because the cuticles are so tight, products including creams, oils and water-based formulas, tend to sit on top of the hair instead of being absorbed.
Always dye dry hair - if your hair's saturated with water, it won't absorb the dye as well. Don't mix shades to create a 'custom' colour - just pick a shade you like, and follow the pack's instructions carefully.
If you're using semi-permanent or demi-permanent hair color, you'll need a developer with a lower volume, between 3 and 20 Vol. If you're using a permanent hair color, you'll need a developer with a higher volume. This is usually between 20 and 30 Vol.
If you want more vibrancy blow dry and apply. If you are doing pieces and not the whole head it's easier to apply to dry or towel dried hair. If doing the whole head, it's easier to apply on wet or towel dried hair. If just enhancing your color or don't want it too bright shampoo, apply in shower on wet hair and rinse.
If you're only depositing color on to the strand, there won't be much damage. Depositing color is about the same as depositing any styling product on your hair. It may be moisturizing, or it could be drying, but it probably won't permanently damage your hair.
Neutral shades like soft blonde, mushroom brown, light copper, and caramel blonde balayage are the easiest to blend gray into (and maintain over time without wanting to shave your hair off).
Because it's drier and more porous than more color-rich shades, grey hair can be more resistant to dye. Plus, as we age, our scalp produces less oil, making our hair coarser and less accepting of color.
your hair is over processed and damaged. when the cuticle is blown open, your hair can't grab color. your best bet would be to go to a professional. they will treat it properly with a proteine filler.
Both protein (keratin) and moisture are essential components of healthy hair—if they're missing, your hair color could fade quickly. If hair is in poor condition (we're looking at you split ends), a protein or moisturizing treatment may be needed before you color.
Red hair is notoriously difficult when it comes to upkeep. While it's the hardest color to fully strip from your hair, it's also the first to fade, often lightening drastically within the first few washes. So unless you're wanting to touch-up your own color at home, it would be wise to skip the scarlet shades.