Non-metal tanning process using sulfonated triazine derivatives
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Solution Overview
Problem
Chrome-based tanning methods are environmentally unfriendly and require additional steps and precise control of enzyme activity, while existing alternatives do not offer effective non-metal tanning solutions that can omit pickling and provide high-quality leather.
Innovation Solution
A non-metal tanning process using a mixture of specific compounds, including sulfonic acid derivatives and alkyleneoxy radicals, in a tanning bath with a pH of 6 to 10, which acts as both a pre-tanning and main tanning agent, eliminating the need for pickling and providing high-quality leather.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If chrome-based tanning is used, then high shrinkage temperature and suppleness are achieved, but environmental friendliness deteriorates
Solution Approach 1:
The invention changes the chemical composition parameters by using non-metallic compounds (sulfonated triazine derivatives, cyanuric chloride derivatives, isocyanates, aldehydes) instead of metallic chromium compounds, while maintaining the crosslinking function to achieve high shrinkage temperature and leather quality without environmental harm
Solution Approach 2:
The invention uses organic compounds that can be applied and rinsed away without persistent environmental contamination, replacing chromium salts with biodegradable or easily removable organic tanning agents that achieve the desired leather properties temporarily during processing
2Reliability
If laccase enzymes are added to tanning bath, then tanning quality is improved, but process complexity increases
Solution Approach 1:
The invention extracts and eliminates the enzyme addition step from the tanning process, using direct chemical crosslinking with sulfonated triazine derivatives and other compounds that provide tanning quality improvement without requiring separate enzyme treatment stages
Solution Approach 2:
The invention uses sulfonated triazine derivatives and cyanuric chloride derivatives as intermediary crosslinking agents that directly bridge collagen molecules, replacing the enzymatic mediation of laccase with chemical mediation that achieves similar quality results through simpler direct reaction
3Strength
If pre-treatment with crosslinking compounds is applied, then resistance to deterioration is improved, but manufacturing complexity increases
Solution Approach 1:
The invention merges the pre-treatment crosslinking step with the main tanning operation by using the same sulfonated triazine derivative compounds for both purposes, achieving resistance to deterioration and complete tanning in a single integrated process rather than separate sequential steps
Solution Approach 2:
The invention makes the tanning agent universally functional by designing sulfonated triazine derivatives that simultaneously provide crosslinking for deterioration resistance, pH buffering, and complete tanning, allowing one compound to perform multiple functions that previously required separate treatment steps
4Loss of time
If pickling is omitted, then process time is reduced, but tanning effectiveness may deteriorate
Solution Approach 1:
The invention performs preliminary pH adjustment and collagen preparation through the bating process itself, which brings the hide to the appropriate pH range (3-6) and collagen state for direct crosslinking, eliminating the need for separate pickling while ensuring tanning effectiveness from the start
Solution Approach 2:
The invention enables the bating process to self-prepare the hide for tanning by naturally adjusting pH and collagen structure through bacterial action, so the hide is automatically ready for crosslinking without requiring additional pickling intervention
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The process achieves high-quality, metal-free tanned leather with improved shrinkage temperature, firmness, and resistance to moisture and perspiration, while reducing environmental impact and simplifying the tanning process by omitting pickling and minimizing water usage.
Implementation Method 1
J. H. Bowes and C. W. Cater in the article 'Crosslinking of Collagen' in J. Appl. Chem., 15, July, 1965, describe some crosslinking tests carried out on collagen of denatured animal tendon (kangaroo tail tendon, KTT) with various crosslinking compounds
Implementation Method 2
a non-metal tanning of outstanding quality can be achieved using the below defined tanning agents - in particular even as complete tanning materials - and tanning methods, which also allow to omit a pickling as conventionally carried out before chrome tanning or aldehyde tanning
Data Source
AI summary
Tanned leather, skin or pelt is produced by non-metal tanning, comprising the step of tanning a bated hide, skin or pelt with a tanning agent (A), the tanning agent (A) being at least a mixture of compounds of formula (I) and formula (II), wherein Hal signifies fluorine or chlorine, R1 signifies hydrogen, C1-8-alkyl or an alkyleneoxy radical of formula (III), - (- C2-3 alkylene - O -)q - H (III) R2 signifies a) phenyl, mono- or di-substituted with SO3M or COOM and optionally substituted also with hydroxyl or C1-4-alkyl or C1-4alkoxy, or b) naphthyl, mono- or di- or tri-substituted with SO3M and optionally substituted also with hydroxyl, or c) C1-8-alkylene, substituted with (S03M) or (COOM), or d) a radical of formula (IV), - (- C2-3 alkylene - O -)p - Y (IV) e) or a radical of formula (IVa), -(C2-3alkylene - O)p -C2-3 alkylene - SO2CH2 CH2O -Y (IVa) m signifies 1 or 2, P signifies 0 or 1, Y signifies hydrogen or -SO3M, q is of from 1 to 10, M signifies hydrogen or an alkali metal cation or an ammonium cation, the ammonium cation being a protonated tertiary amine or a quaternary ammonium cation, R3 signifies hydrogen or chlorine, in a tanning bath, the tanning bath having a pH of from 6 to 10 at the beginning of tanning step.