Say if the dye is patchy or too light. A leveling oil that also lightens the shade is the wrong tool when the customer already approved depth.
Level first, fix second
A dye fixer on an unlevel dyeing makes a fast unlevel dyeing. Leveling belongs to the syntan and the dyeing oil. Fixing belongs to the dye-fixing agent once the shade is even.
The dispersing fatliquor also claims stability to electrolytes and a dispersing effect on anionic dyes and pigment preparations. That is a dye-bath tool, including titanium dioxide dispersions for white work, not only a softness oil.
How much lightening is acceptable
Some leveling agents work by slowing dye strike and the shade looks weaker. Esteem’s dispersing grade specifically notes leveling without excessive lightening. If your current oil strips the shade, say so, because the replacement target is levelness at the same depth.
Powder syntans fill and can change the surface the dye sees. A fuller leather often looks deeper or flatter. Judge depth on a finished thickness, not on a wet swatch.
Which lever
Semi-chrome and combination leathers are where this dispersing grade’s combining capacity is called out. Chrome shoe upper with a different dye class still needs the dye named.
Temperature and float change strike more than a tenth of a percent of auxiliary. Log them.
| Problem | First lever | Second lever |
|---|---|---|
| Patchy anionic dye | Dispersing dyeing oil or syntan | Fixer only after |
| Weak shade | Less leveling, more dye | Not more dispersant |
| White pigment spots | Dispersing grade for pigment | A softness top oil |
| Unlevel and empty | Powder syntan | Then oil |
Dye strike is an exhaustion race
Anionic dyes exhaust onto cationic chrome leather quickly, especially at low float and falling pH. The grain takes dye first. The centre stays pale. A dispersing fatliquor that is only weakly anionic wets the interior and slightly retards the surface strike so more dye is still in the liquor when the centre is ready to take it. That is levelling by distribution, not by bleaching.
A strong anionic main fatliquor can compete so hard that the shade stays light, or it can break and deposit dye-oil complexes on the grain. The dyeing-oil grade on the fatliquor table is the one described for levelness. The softness oil is a different line and should stay constant while levelness is being fixed.
Syntans change the sites
Phenolic and other syntans add anionic character and fill. They can level dye too, because they occupy or modify sites, and they always change fullness and often the hue. If the brief is a fuller leather with a different break, a syntan is the right conversation. If the brief is the same hand with a more even shade, a syntan is a second variable you did not ask for.
Auxiliaries such as dye dispersants sit in the same argument. Stacking a syntan, a dispersing oil, and a dye auxiliary in one bath makes a pale, over-retarded shade that no one can assign. Add one leveller at a time.
What an even cut looks like
Cut the leather after dyeing and before fatliquor topping. The cross-section should approach the surface shade. A dark ring and a pale centre is a penetration failure. A pale leather throughout is over-retardation or an exhausted bath that was too short of dye. These are opposite corrections.
Name the dye class, the float, the pH profile, and whether fullness may change. The dispersing fatliquor is then a levelness tool with a known effect on softness, not a mystery second retan.
How to Specify with Esteem
- State anionic dye and the fibre: chrome, semi-chrome, or veg.
- Say patchy, bronzed, or too weak.
- Trial a dispersing dyeing oil and a powder syntan separately.
- Keep fatliquor softness offers out of the dye ladder.
- Approve shade under the customer light after drying.
Read the dispersing-fatliquor note on fatliquors and powder syntans.