Enzymes for Leather
Enzymes for Leather
CHEMICAL DEGREASING
Chemical surfactants such
as nonyl phenol ethoxylate are usually used for both sheepskins and pigskins
but they are very detrimental to the environment.
Enzymatic Degreasing
Lipases are a type of enzyme that specifically degrades fat and
so cannot damage the leather itself. Lipases hydrolyse not just the fat on the
outside of the hides and skins, but also the fat inside the skin structure.
Once most of the natural fat has been removed, subsequent chemical treatments
such as tanning, re-tanning and dyeing have a better effect.
The main advantages of using lipases are a more uniform colour
and a cleaner appearance. Lipases also improve the production of hydrophobic
(waterproof) leather; makers of leather for car upholstery have commented that
'fogging' is reduced. This is the term for the build-up of a film of chemicals
on the inside of car windscreens
Lipases represent a more environmentally sound method of
removing fat. For bovine hides, lipases allow chemical fat removers called tensides
to be replaced completely. For sheepskins, which contain up to 40% fat, the use
of solvents is very common and these can also be replaced with lipases and
surfactants. Solvents tend to dry out the skin and give it a pale colour
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Palkodegrease
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Lipase for degreasing in neutral to alkaline pH conditions
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Palkodegrease AL
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Lipase for degreasing in acidic pH conditions
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TEXTILES
INDUSTRY
Many garments are subjected to a wash treatment to give them a
slightly worn look; example is the stonewashing
of denim jeans.
In the traditional stonewashing process, the blue denim was
faded by the abrasive action of pumice stones on the garment surface. Nowadays,
denim finishers are using a special cellulase.
Cellulase works by loosening the indigo dye on the denim in a
process know as 'Bio-Stonewashing'. A small dose of enzyme can replace several
kilograms of pumice stones.
The use of less pumice stones results in less damage to garment,
machine and less pumice dust in the laundry environment.
BioStonewashing has opened up
new possibilities in denim finishing by increasing the variety of finishes
available. For example, it is now possible to fade denim to a greater degree
without running the risk of damaging the garment. Productivity can also be
increased because laundry machines contain fewer stones or no stones and more
garments.
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Palkowash
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Cellulase for bio-stonewashing denims used in garment wet-processing
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Palkostone
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Cellulase for bio-stonewashing denims used in garment
wet-processing
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Palkocel
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Cellulase for bio-stonewashing denims used in garment
wet-processing
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