Crust leather
Crust leather
Crustleder ist Leder, das nach der Gerbung getrocknet, aber noch nicht gefärbt ist. Bei chromgegerbten Ledern spricht man dann von "Chrom-Crust" oder bei pflanzlich gegerbten Ledern von "Pflanzen-Crust". Ein weiterer Begriff für "Crustleder" ist "Borke" oder "Borkeleder".
Crustleder wird nur selten weiterverarbeitet. Meist werden die Leder vor der Verarbeitung noch gefärbt und zugerichtet.
"Pflanzencrust" - "Chromcrust"
Pflanzliche Crustleder verarbeitet.
Unusual. Chrom-Crust weiterverarbeitet. Die Färbung ist so nicht ansprechend. Daher eher eine "Billig-Lösung".
Crusting
Crusting is part of the tannery working steps for leather produciton. The parts of working steps in the leather production process are called, preparatory stages, tanning, crusting and surface coating.
Crusting is when the hide is thinned, retanned and regreased. Often a dye process is included in the crusting. Also part of the crusting is the drying and softening.
Crusting may include the following working steps depending on the type of leather:
- Splitting: The leather is split into one or more horizontal layers.
- neutralisation: The pH of the leather is adjusted.
- Retanning: Additional tanning imparts properties.
- Dying: The leather is coloured in the drum.
- Fixation: Unbound chemicals are chemically bonded or removed from the fibres.
- Whitening: The colour of the leather is lightened.
- Fatliquoring and Stuffing: Fats, oils and waxes are added between the fibres to soften the leather.
- Shaving: The leather is thinned using a machine which cuts leather fibres off the flesh side.
- Wetting and Conditioning: Leather has to be rehydrated depending on the following working steps.
- Sammying: Water is squeezed out the leather.
- Drying: The leather is dried to different moisture levels.
- Filling: Dense chemicals are added to make the leather harder and heavier.
- Stripping: Superficially fixed tannins are removed.
- Softening: Physical softening of the leather by by tumbling and stacking.
- Buffing: Abrasion of the surfaces of the leather to reduce nap or grain defects.
Additional information