Overview
SIST EN ISO 4098:2018 specifies internationally recognized chemical test methods for the determination of water-soluble matter, water-soluble inorganic matter, and water-soluble organic matter in leather. This standard is applicable to all types of leather and is used in both research and industrial settings to assess and compare leather quality. Developed by IULTCS and standardized throughout Europe, this method is critical for accurately characterizing leather's chemical properties, supporting product quality, safety, and regulatory compliance in the leather industry.
Key Topics
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Scope and Applicability
- Suitable for all leather products, including finished goods.
- The procedure's results are influenced by sample preparation, extraction temperature and period, and leather-to-water ratio.
- Standardization is crucial for comparability; precise adherence to the test method is required for consistent results.
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Testing Procedure
- Involves extraction of ground leather using controlled conditions.
- Quantification of water-soluble matter via drying and weighing.
- Further classification of water-soluble matter into inorganic (ash) and organic fractions by ashing at a specified temperature.
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Specific Considerations
- Ammonium salts present in the extract are counted as water-soluble matter and, upon ignition, are accounted for in the organic matter total unless separately quantified.
- Recommendations are provided for sample weight, extraction volumes, and adjustment in case of low inorganic content.
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Reporting
- Requires clear documentation of the methodology, conditions, and any deviations.
- Results should be reported to one decimal place and indicate if calculated on a dry-substance basis.
Applications
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Quality Control
- Determines the chemical purity and processing quality of leather materials.
- Enables manufacturers and suppliers to ensure compliance with industry standards and buyer specifications.
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Regulatory Compliance
- Used for meeting regional and global regulatory requirements regarding leather composition.
- Supports traceability and transparency in supply chains, particularly for industries that mandate chemical testing of materials.
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Research and Development
- Assists in the development of new leather treatments, processes, or products by providing detailed insights into water-soluble fractions.
- Allows comparison of different tanning and finishing methods for their impact on leather chemistry.
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Consumer Assurance
- Provides measurable indicators of leather cleanliness and resistance to chemical degradation, supporting claims of durability and safety.
Related Standards
- ISO 2418 - Leather - Chemical, physical and mechanical and fastness tests - Sampling location.
- ISO 3696 - Water for analytical laboratory use - Specification and test methods.
- ISO 4044 - Leather - Chemical tests - Preparation of chemical test samples.
- ISO 4048 - Leather - Chemical tests - Determination of matter soluble in dichloromethane and free fatty acid content.
- ISO 4684 - Leather - Chemical tests - Determination of volatile matter.
These standards are referenced within SIST EN ISO 4098:2018 for guidance on sample collection, preparation, and related chemical analyses, ensuring harmonized testing procedures across laboratories and manufacturers.
Keywords: leather chemical testing, water-soluble matter in leather, ISO 4098:2018, leather quality control, water-soluble inorganic matter, water-soluble organic matter, IULTCS, EN ISO 4098, chemical analysis of leather, leather standards.
