How to use GDS Hair Dye Shampoo
Ten minutes in the shower.
Two or three washes.
Gloves on, Part 1 and Part 2 mixed in your palm, a visible layer over wet hair, ten minutes, then rinse and shampoo. Full coverage on heavy grey builds over two or three washes. Patch test 48 hours before every use — this is a permanent oxidative dye. No shade contains PPD; all three use PTD (toluene-2,5-diamine sulfate), which cross-reacts in many people allergic to PPD, with resorcinol.
The pack you'll receive.
The front of the pack is printed in Korean. We send the Korean-market product exactly as it leaves the factory, with no re-labelling and no repacking for export. All three shades ship as the renewed two-part set: no PPD, a 150ml colour shampoo and a 150ml developer.
BLACK
BROWN
DARK BROWN
Mix in your palm, then work it through wet hair. Part 1 (colour shampoo) and Part 2 (developer) in equal amounts, right before use. A visible layer over the grey — if you can see hair through it, add more. Roots, parting and temples first, then the lengths.
Wait ten minutes, rinse lukewarm, then shampoo. Ten minutes for every shade. Rinsing early is where most "lighter than I expected" comments come from.
Full coverage builds. Colour lands on the first wash. The second lands darker, and heavy or resistant grey usually needs a third. From there it's roots-only every two to four weeks.
Five things to have sorted before you mix.
Patch test, every time
A dab behind the ear, 48 hours, uncovered. Any redness or itch means stop. Repeat before each use, not only the first.
Gloves on first
A pair comes in the box. It stains skin and nails for days — the most repeated complaint in the reviews, almost always from bare hands.
An old towel
Tile and porcelain rinse clean with soap. Cotton keeps the colour.
Mix right before use
One bottle, two parts: Part 1, the colour shampoo, and Part 2, the developer, pumped together. Equal amounts — about 10g of each — mixed in a gloved palm. Mix only what you will use.
Scalp hair only
Not beards, not brows, not lashes. Facial skin reacts far more readily to the dye intermediates (PTD and its couplers, in every shade).
Wet hair, ten minutes, seven steps.
The whole thing happens in the shower. One bottle with two parts — the colour shampoo and the developer — pumped together and mixed in your palm right before use.
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01
Gloves on A pair comes in the box. Put them on before you open the bottle.
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02
Wet your hair, squeeze out the excess Damp, not dripping. Water running down your neck carries dye with it.
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03
Mix Part 1 and Part 2 in your palm Right before use, equal amounts of the colour shampoo and the developer — about 10g of each for a parting and temples, more for heavy grey. Mix only what you will use.
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04
Work a visible layer through like shampoo Start where the grey is — usually roots, parting and temples — then bring the lather through the lengths. If you can see hair through it, mix a little more.
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05
Wait ten minutes10 min Ten minutes for every shade and any amount of grey. Rinsing early is where most "lighter than I expected" comments come from.
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06
Rinse lukewarm, then shampoo Rinse until the water runs clear, wash with shampoo, then a last lukewarm rinse. Hot water opens the cuticle and lets colour escape.
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07
Skip the conditioner Six plant oils are in the colour shampoo: avocado, macadamia, jojoba, olive, grape seed, camellia. Dry as usual.
Wet hair for touch-ups, dry hair for heavy grey.
Wet hair · everyday
The gentler method. Lather in the shower, ten minutes, rinse. Use it for roots and touch-ups once the first full application is done.
Dry hair · first application on heavy grey
No water diluting the dye, so it takes more evenly and lands a shade deeper. Same gloves, same mix, same ten minutes. Rinse the same way.
Colour lands on the first wash. Full coverage builds.
Wash 1
Colour lands. How much grey it covers depends on how much grey there is. Scattered grey gets close; heavy white stays lighter.
Wash 2 · next day
Lands darker than the first because the pigment builds. This is where most people with 60 to 70 percent white land the result.
Wash 3
Full, even coverage on resistant hair. From here it is roots-only every two to four weeks as the line shows.
The result is permanent in the chemical sense: colour forms inside the hair shaft and does not rinse out. It leaves only as the hair grows. Roots-only use makes a bottle last four to six months; all-over on heavy grey runs closer to a bottle a month. Our bottle calculator walks through it.
Match the hair you have now, not the hair you want.
Black
Lands exactly as dark as it says and does not go warm. Also does not forgive a shade you did not want.
150ml + 150mlDark Brown
The safer brown. Pick this over Brown if you are more than half grey; it settles without turning brassy.
150ml + 150mlBrown
Sits on a warm base. Reads reddish when there is a lot of white under it or when rinsed early. Give it the full ten minutes.
150ml + 150mlAll three shades ship as the same two-part set — a 150ml colour shampoo and a 150ml developer, same label design; only the shade differs.
What produces most of the bad results.
No gloves. Stained hands for days — and a pair comes in the box.
Rinsing before ten minutes. Lighter, patchier; brown reads warm.
A film instead of a layer. If you can see hair through it, add more.
Brown on mostly white hair. Goes brassy. Dark Brown is the safer call.
Hot rinse. Pulls colour back out.
Beard or brows. Not what it is for, and not where you want an oxidative dye.
Skipping the patch test because last time was fine. That is exactly how sensitisation announces itself.
Patch test 48 hours ahead.
Every time, not just the first.
A small dab behind the ear or on the inner elbow, left uncovered for 48 hours. Any redness, itching or swelling means do not use it. No shade contains PPD; all three are built on PTD (toluene-2,5-diamine sulfate), a close relative that cross-reacts in many people allergic to PPD, with resorcinol and aminophenol couplers — sensitisation can appear after years of trouble-free use, which is why the test is repeated before each application.
No PPD, no ammonia, no parabens — and still a real permanent dye.
The colour comes from a primary intermediate — PTD (toluene-2,5-diamine sulfate) in all three shades, with no PPD — and resorcinol plus m- and p-aminophenol as couplers; Black adds 2,4-diaminophenoxyethanol HCl and Brown adds 4-amino-2-hydroxytoluene. The hydrogen peroxide in Part 2 develops it, and ethanolamine alkalises it instead of ammonia. That is what covers grey and what carries the allergen risk; there is no version that keeps one without the other. PTD cross-reacts in many people allergic to PPD, so we grade every ingredient and publish the list rather than let "PPD-free" stand on its own.
● high · ● mid · ● low — our screening's assessment, not a safety determination
The full declared lists for every shade, each ingredient graded, are on the ingredients page. How a dye shampoo does this chemically, and why "PPD-free" is not the safety badge it looks like, is in our piece on hair dye shampoos and the PPD question.
Quick answers.
Do I use GDS hair dye shampoo on wet or dry hair? +–
Mix Part 1 and Part 2 in your palm first. Wet hair, worked through like a shampoo, is the everyday method. Apply to dry hair for more intensity on white, wiry or heavy grey.
Do I have to mix GDS hair dye shampoo? +–
Yes. It is a two-part dye: a 150ml colour shampoo (Part 1) and a 150ml developer (Part 2). Right before use, mix equal amounts in a gloved palm — about 10g of each — and use it straight away. Mix only what you will use.
How long do I leave GDS hair dye shampoo on? +–
Ten minutes, for every shade and any amount of grey. Then rinse with lukewarm water, wash with shampoo and rinse again. Rinsing early is the usual reason for a lighter result.
Does GDS hair dye shampoo stain skin? +–
Yes. It stains skin and nails for a few days, which is the most repeated complaint in the reviews. Wear the gloves — a pair comes in the box. Surfaces rinse clean with soap and water.
Will one wash cover all my grey? +–
Plan on two or three washes for full coverage. Scattered grey gets there sooner than heavy or resistant white hair, and the second wash lands darker than the first because the pigment builds. The dry-hair method on the first application shortens the gap.
Do I need a conditioner after GDS hair dye shampoo? +–
No. The formula includes avocado, macadamia, jojoba, olive, grape seed and camellia oils. If your hair runs very dry you can add one — choose a colour-safe conditioner so it does not fight the next application.
How do I patch test GDS hair dye shampoo? +–
Apply a small dab behind the ear or on the inner elbow, leave it uncovered for 48 hours, and do not use the product if there is any redness, itching or swelling. Repeat the test before every application. No shade contains PPD, but all three contain PTD (toluene-2,5-diamine sulfate), a close relative that cross-reacts in many people allergic to PPD, plus resorcinol and aminophenol couplers.
Can I use GDS hair dye shampoo on my beard or eyebrows? +–
No. It is formulated and tested for scalp hair only. Facial skin is far more reactive to hair-dye intermediates like PTD, and the eyes are close by.
Where does it ship from, and how long does it take? +–
Made in Korea and dispatched from Seoul within one to three business days with a tracking number. After dispatch, typically seven to fourteen business days to the US, Canada and the UK, and five to twelve to Australia, Hong Kong and Singapore.
Black, Brown, Dark Brown.
Every ingredient graded on the product page.
Ships from Korea within one to three business days, tracked. Patch test 48 hours before every use.