Exhaust and usually acidify the anionic main fatliquor before a cationic top. Do not pour them in together.
Sequence is the specification
Anionic main fatliquors exhaust onto the leather and leave a bath that is still not a safe home for a cationic product if they are combined early. The practical rule is to finish the anionic stage, then top with cationic or nonionic chemistry for surface handle.
The Esteem cationic paste is dilutable, stable to acids, salts, hard water, and chrome, and compatible with cationic and nonionic products. That compatibility list does not include a rich anionic float.
Suede main oil versus grain top
On chrome suede the same grade can be the main fatliquor. On grain it is described as a top. Those are different offers and different moments. A top percentage used as the only oil on a thick hide leaves the centre dry.
Lightfastness is a published reason to consider this grade on pale work, together with the nonionic handle modifier and the lightfast synthetic. Charge still decides when it can be added.
Failures
If spots appear, do not add more oil. Strip or wash back only with a plan, and change the sequence on the next pack.
Handle panels should be compared after staking. Wet slip is not the top-fatliquor result.
| Practice | Result | Correction |
|---|---|---|
| Cationic into anionic bath | Precipitate and spots | Separate stages |
| Top oil as the only oil | Dry centre | Main anionic first |
| No exhaustion before top | Greasy grain | Exhaust, then top |
| Nonionic wanted, cationic sent | Charge surprise | Name the ion |
Opposite charges are the point
Chrome leather after an anionic fatliquor and an anionic dye still has anionic character at the surface. A cationic fatliquor, typically a condensate that is cationic in the acid top bath, exhausts onto that surface. Because it exhausts quickly it does not travel far into the centre. The centre keeps the softness of the main oil. The surface gets the smooth, dry handle the top is for.
That mechanism only works if the cationic meets the leather rather than the leftover anionic chemicals in the liquor. A bath that has not exhausted, or a bath that still contains anionic syntan and dye, will complex the cationic product before it reaches the fibre. Dropping the float or running a short wash between stages is part of the chemistry, not a housekeeping step.
Handle without filling the centre
Top fatliquors are dosed low because the surface area of the grain, not the thickness of the hide, is the target. A high cationic offer feels good in the drum and then blocks finish wetting, darkens aniline shades, or leaves a waxy write on suede. The grades described as top fatliquors for grain, or as main fatliquors for chrome suede, are being asked to do different depths of penetration. The suede case is not a permission to raise the top offer on grain.
Electrolyte stability matters in this bath. Residual salt from the dye house can dull a cationic emulsion that was stable in fresh water. The high-electrolyte, high-lightfastness cationic grades are the ones the table points at when the top bath is not a clean float.
How to confirm the split worked
The liquor after the anionic stage should be largely exhausted before the cationic goes in. The leather after the top should feel smoother without a large change in cross-section softness. A cut that is suddenly softer all the way through means the cationic penetrated like a main oil, which usually means the offer was high or the leather was still very open.
If finish adhesion fell, the top is sitting as a release layer. Reduce it or move it earlier and exhaust it, rather than adding a harsher finish binder. State whether the top is for grain handle, suede, or a cationic dye shade. Those three uses are not one percentage.
How to Specify with Esteem
- Confirm the main fatliquor is anionic and exhausted.
- Add the cationic top in a fresh or exhausted float, not into a rich anionic bath.
- Use it for surface handle or for chrome suede as the table describes.
- Do not use it as the only oil on a heavy bovine upper unless that trial exists.
- Check for spots and grain grit after drying.
The cationic grade on fatliquors is compatible with cationic and nonionic products, and is described as a top fatliquor for grain and a main fatliquor for chrome suede.