Not the day of the bleach. That is the first thing to say about this formula, because it is the one toner page built on 20 vol, and 20 vol on a scalp lightened a few hours ago burns. The pros who put liquid permanent toners on camera warn about it, and the ones who use them wait a day or two, on unwashed hair, with the scalp’s own oil back.
This is the tone-and-nudge: a 9 that cannot take another bleach and wants to be a lightest blonde anyway gets a permanent shade at level 10 on 20 vol, which cancels the pale yellow and lifts a little at the same time.
What 20 vol buys and what it costs
A toner does not lighten, and a demi at level 10 on a 9 breaks the rule every colorist repeats, tone at the level you reached or darker; it gives you a cool 9, the level 9 to 9 page. Ten vol or lower with a demi is a toner. Twenty vol with a permanent shade is color that lifts while it deposits, the T18 class, labeled for pale yellow hair only for that reason. Under a 10.2 (10V) or a 10.21 (10P) the developer lifts a little of the pale yellow while the violet covers the rest. Violet cancels yellow, and at this depth there is no orange for blue to work on, so the ash-heavy 10.1 stays in the drawer.
What it buys: half a level on healthy hair, close to a full level on hair lifted only once, and a tone that outlasts a demi’s. What it costs: the burn on a fresh scalp, breakage on ends that already stretch, a gray, dingy cast on hair lifted past pale yellow, and orange on any natural regrowth it touches. On very porous hair it buys nothing; there is no lift left to have.
Mix on a scale, 40 g and 40 g, the ounce to an ounce of the US pros, or the line’s own ratio if its directions say 1:1.5. I write the start level on masking tape on the bowl, because by minute 25 the temptation is to decide the hair was a 9.5 all along, and the tape settles it. The developer mix calculator does the grams.
Roots first, then the clock
Roots first, ends last, on dry unwashed hair, with enough product to saturate every section; more people under-saturate than over-process. The root is the least porous hair on the head and takes longest, and it sits on a warm scalp, so it is the section to watch at 25. The ends grab and finish early. Natural regrowth rules this formula out; 20 vol lifts new growth orange under a violet shade.
At 5 and 10 minutes nothing visible has happened. At 15, wipe a strand at the mid-length: paler, a shade cooler, a little yellow still under the violet. At 25 the root should read close to a 10, and around 30 the mid-lengths catch up. Thirty-five is the stop; after that the 20 vol is doing damage and the violet covers nothing new. It looks purple on the head the whole time, and that tells you nothing until it is rinsed and dried.
The ends go on last and get wiped first; on hair lifted more than twice they are done at 12 to 15 minutes and drift violet after.
Which road for which hair
| Hair condition | Route | What you get |
|---|---|---|
| Natural 9, or lifted once; a wet strand stretches and returns | One more careful bleach session, then 10.21 demi | A true, even 10 |
| Lifted twice, still elastic, ends a little dry | This formula, 30 to 35 min | A 10 at the root, a cool 9.5 below |
| Lifted three or more times; a wet strand pulls long and stays | 10.2 or 10.21 demi on 10 vol, 15 min | A cool 9, no lift |
| Uneven: 9 at the root, 8 through the mids | Bleach the mids only, then tone at 9 | A clean 9 now, the 10 next time |
| A 9 that wants to look lighter without more lift | Root shadow, 8N at the root, 9V or 9P through the lengths, 10 vol | Lengths that read lighter against the root |
Where it goes wrong
Too long, and it goes violet at the ends and then a flat gray-mauve. Wrong level, the common one, and you get a warm 8.5 with the yellow showing through. A swimmer’s chlorine green cast that only shows wet, which the 20 vol brings up under the violet as a dingy, greenish tinge that takes two clarifying washes and a 10.21 gloss. And damp application, which thins the mix and leaves the nudge at nothing.
After the rinse
The lift is permanent. The tone fades in five to seven weeks toward the pale yellow underneath, ends first, and a violet gloss on 10 vol puts it back without another gram of 20 vol. Purple shampoo every second or third wash keeps the violet topped up between glosses; it is maintenance, and it does not tone a head that has faded all the way back. The toner selector will say which violet if the level has moved.
Or shadow the root
There is a way to look lighter without lifting anything, and it is routine in any salon that does blondes. Leave the level where it is and put a darker demi at the root, an 8N (8.0), an inch or so down, blurred into a 9.2 (9V) or 9.21 (9P) demi through the lengths, all on 10 vol, towel-dried, fifteen minutes. The eye reads the lengths against the root, and a 9 next to an 8 shadow reads lighter than the same 9 toned flat. No 20 vol and nothing to burn. A root tap looks expensive, and it grows out softer than a nudged 9 against its natural root.
