Hair Dyes: How to Choose and How to Apply Them
Tre Pi Profumerie offers hair dyes and colours from the leading brands, from permanent formulas to tone-on-tone, right through to fantasy colours. Free shipping over € 79,90, free samples with every order, returns within 14 days. Physical shop in Marcianise (CE) and phone support to help you choose the right shade.
Permanent, Tone-on-Tone or Temporary?
This is the first decision to make, even before the colour itself.
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Permanent colour — mixed with a developer, penetrates the hair fibre, covers grey hair 100% and can lighten by 1-3 tones. It doesn't wash out: it grows out with the hair, with regrowth visible after 3-4 weeks.
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Tone-on-tone — low-volume developer, doesn't lighten, partially covers grey hair. Fades after 20-25 washes, leaving less noticeable regrowth. The safest choice for a first change.
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Colour rinse — ammonia-free, adds shine and reflects. Partial grey coverage.
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Direct colour — pigments that deposit without any chemical reaction. Lasts just a few washes, with full results only on light or bleached hair. This is the fantasy colour family.
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Colour-depositing shampoo — deposits pigment on the surface, fades after 4-8 washes. Handy for trying out a shade without commitment.
How to Read the Number on the Box
A dye's code follows the pattern tone level . reflect.
The digit before the dot shows how light the colour is: 1 black, 4 brown, 6 dark blonde, 7 blonde, 9 very light blonde, 10 lightest blonde.
The digits after the dot indicate the reflect: .0 natural, .1 ash, .2 irisé, .3 golden, .4 copper, .5 mahogany, .6 red, .7 brown.
So a 7.1 is an ash blonde, a 6.3 a golden dark blonde. Coding can vary slightly between brands: always check the colour chart on the box.
What Colour Can You Really Achieve
This is where mistakes happen most often. A permanent dye lightens by a maximum of 2-3 tones from the starting base, and it won't lighten hair that's already dyed at all: artificial colour can't be removed with more colour.
So:
- Going from brown to light blonde in one step isn't possible with a dye. It requires bleaching, which is a salon service.
- On already coloured hair, you can go the same tone or darker, or refresh the reflect.
- Going from blonde to brown is simple, but requires pre-pigmentation if the hair is heavily bleached, otherwise the result can turn green or grey.
- The result depends on the starting base: the same shade on brown hair and on blonde hair gives two different colours.
Covering Grey Hair
Grey hair has no pigment and a more resistant structure. For full coverage you need permanent formulas from the natural series: pure fashion shades (golden, copper, ash) tone down grey rather than covering it completely.
If grey exceeds 50%, choose a shade with the natural digit (.0) or mix it with the fashion colour. Temples and the front area are usually the most resistant: apply there first and allow the full processing time.
Before Colouring: The Skin Test
Oxidative colours contain molecules that can potentially cause sensitisation. The test should be done 48 hours before every application, even if you've used the same product before: sensitisation can develop at any time.
Apply a small amount of the mixture to the crease of the elbow or behind the ear, let it dry and don't wash for 48 hours. If redness, itching or swelling occurs, do not proceed.
Do not colour irritated skin, wounds or areas with ongoing dermatitis, and never apply oxidative colours to eyebrows or eyelashes.
After Colouring
- Wait 48-72 hours before the first wash.
- Use shampoo and conditioner for coloured hair, with an acidic pH.
- Wash with lukewarm water: heat opens the cuticle and washes out pigment.
- On blondes, alternate with an anti-yellow shampoo to counteract warm reflects.
- In summer, protect the colour from UV rays, which oxidise the pigment.
- A weekly hair mask makes up for the dehydration caused by colouring.
Frequently Asked Questions
How Often Can You Redo the Dye?
Regrowth is touched up every 4-6 weeks, applying colour only to the new growth. Going over the full length every time overexposes the hair and makes it porous.
Can Dye Be Used During Pregnancy?
Guidance varies and the question should be put to your doctor. In general, it's suggested to prefer ammonia-free formulas, techniques that avoid contact with the scalp, and well-ventilated environments.
Why Does the Colour Turn Orange?
Because underneath the dark melanin there's warm pigment that emerges as soon as the hair lightens. Neutralising it requires an opposite reflect: ash or irisé on yellow tones, blue on orange tones. For major lightening, this is a job for the salon.
Are Ammonia-Free Dyes Less Damaging?
They're gentler on the scalp and free from a strong smell, but they use other alkalising agents and are still oxidative colours. They also have a lower lightening power.
Can I Lighten a Dye That's Too Dark?
No, not with another dye. You need colour stripping or bleaching, procedures that are best carried out in a salon to avoid damaging the hair fibre.
How Much Product Do You Need?
One box is enough for short hair or a regrowth touch-up. For long or very thick hair, you'll need two.
Want a Tailor-Made Result?
Major lightening, colour correction, bleaching and techniques such as balayage and highlights require an assessment of the starting base and professional products: these are salon services. If you're a professional, discover our professional colour range and activate the dedicated price list.
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For help choosing: 0823 838002, Monday to Friday 9am-6pm, or on WhatsApp.
