Why Porosity Changes Everything — and How to Avoid Over-Darkening
One of the most common causes of over-dark, uneven, or patchy brows is not the tint itself — it’s a misunderstanding of hair porosity.
Whether brows have been laminated or are in their natural state completely changes how they absorb pigment. Understanding this difference is essential for delivering consistent, high-quality results.
What Happens to Brow Hair During Lamination
A brow lamination is a controlled chemical restructuring process.
During treatment, alkaline solutions are used to:
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Open the cuticle
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Soften the hair
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Break and reform internal bonds
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Reshape the brow
Even when followed by professional fixing and conditioning steps, this process temporarily alters the structure of the hair.
After lamination, brow hairs become:
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More open
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More porous
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More absorbent
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More receptive to external molecules
In simple terms:
laminated brows act like a sponge.
Understanding Hair Porosity
Porosity refers to how easily hair absorbs and retains moisture and pigment.
Low Porosity (Typical of Natural Brows)
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Cuticle lies flat
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Slower absorption
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More resistant to colour
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Requires longer processing time
High Porosity (Common After Lamination)
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Cuticle is more open
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Rapid absorption
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Holds pigment quickly
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Prone to over-darkening
Lamination shifts brow hair from lower or medium porosity into a temporarily high-porosity state.
Read our blog post on porosity here.
The Science: Why Laminated Brows Absorb Tint Faster
Hair is made of keratin proteins protected by overlapping cuticle scales.
During lamination:
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Alkaline products lift the cuticle
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Internal bonds are reorganised
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The cortex becomes more accessible
Even after neutralising and nourishing, microscopic gaps remain in the cuticle structure.
These gaps allow:
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Dye molecules
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Oxidants
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Pigments
…to penetrate much faster than on untreated hair.
This is why tint behaves differently on processed brows.
Tinting Laminated Brows: Timing Is Everything
Because laminated brows are highly porous, pigment uptake happens rapidly.
In many cases:
A laminated brow can reach full colour depth in as little as 30 seconds to 2 minutes.
Some clients with very porous hair may achieve their desired result in under one minute.
This makes observation more important than timing.
When tinting laminated brows, professionals must:
✔️ Apply evenly
✔️ Start timing immediately
✔️ Check development constantly
✔️ Remove as soon as depth is reached
Leaving tint on “just in case” is one of the fastest ways to over-darken.
Shop our range of tints here.
The Risk of Over-Darkening on Processed Brows
When pigment enters porous hair too deeply:
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Colour becomes too intense
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Tones can appear flat or muddy
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Brows may look harsh
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Fading becomes uneven
Once over-deposited, this colour cannot be easily corrected.
Prevention is the only solution — and prevention comes from monitoring.
Tinting Natural, Unprocessed Brows
When brows are in their natural state, the cuticle remains compact and protective.
This means:
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Slower pigment penetration
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More controlled development
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Greater predictability
For most unprocessed brows, standard tint timing is:
Approximately 10–14 minutes
This allows enough time for pigment to gradually enter the cortex and develop evenly.
However, even with natural brows, individual variation matters.
Hair thickness, previous tint history, skin type, and lifestyle all influence results.
Why No Two Brows Behave the Same
Even within the same client, brows can differ.
Factors that affect tint uptake include:
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Previous laminations
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Sun exposure
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Skincare products
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Retinol use
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Oil production
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Hair thickness
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Ethnicity and genetics
This is why rigid timing rules don’t work.
Professional tinting is about assessment and adjustment — not following a clock blindly.
Best Practice: Tinting Based on Hair Condition
For Laminated Brows
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Use lighter or diluted shades when needed
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Apply thin, controlled layers
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Start checking at 30 seconds
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Remove as soon as tone is achieved
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Avoid maximum processing times
For Natural Brows
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Allow full development time
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Monitor every few minutes
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Adjust based on density and porosity
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Avoid rushing the process
The Takeaway
Processed and natural brows are not comparable surfaces.
After lamination, brows become temporarily high-porosity, highly absorbent, and extremely responsive to pigment.
This is why:
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Laminated brows may only need seconds to minutes
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Natural brows may need 10–14 minutes
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Monitoring is essential
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Over-darkening is preventable
Understanding this science is what transforms good artists into exceptional ones.
It protects your work, your reputation, and your clients’ confidence.
