皮革化学.ppt

Leather
Art & Technology
QC Training
Shanghai November 9th-15th, 2009
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Introduction
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Introduction
Manufacture of leather is one of the oldest technological profession.
Historically leather production was made by skilled tanners in very small unit : it was a craftsmanship.
When Industrial Revolution started (1850), meat consumption increased and consequently source of hides increase tremendously.
munication and transport allowed to import foreign hides, then tanneries grew to un-precedent size.
Tannery e an “industry”.
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Introduction
From the first industrial tannery in Philipsburg
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Introduction
To a modern tannery
Bader Head-Quarter
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Leather Technology
Leather structure = Corium
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Leather Technology
As tanners we have the chance to work on a live material : Collagen
Protein containing both acid and basic amino acids groups, non polar amino acids and relatively high percentage of proline and hydroxyproline.
Production of leather can be looked upon three steps :
Removal of ponent (hair, fats,…)
React work with tanning material to get a stabilized fiber structure
Build onto the tanned fibers characteristic of fullness, softness, lubrication, color, then finish the fiber surface and produce a useful product
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Leather Technology
BEAMHOUSE
Soaking
Liming
Fleshing
De-liming
Bating
Pickling
Tanning
Remove dirtiness, blood, soluble proteic substances
Remove hair and epidermis
Remove excess of flesh
Remove excess of lime and reduce pH to 7-
Enzimatic proteolitic fiber relaxing
Reduction of pH to 2- and adding of salt (osmothic internal fiber pressure control) to prepare to tanning
Tanning by Chrome salt or by vegetable tannins
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Leather Technology
WET-END
Shaving
Soaking
Retan
Neutralize
Fatliquor
Dye
Operation to get needed uniform leather thickness
Washing and reduce pH to -
Using Chrome salt, syntan