ASTM D3790-17

Standard Test Method for Volatile Matter (Moisture) of Leather by Oven Drying

SIGNIFICANCE AND USE
4.1 The result obtained by this test is normally considered to be the moisture content of the leather sample. This result is used to correct all other chemical tests to a moisture-free basis.  
4.2 Materials that are volatile under these conditions, other than water, may be present in the leather, although their amount in any normal leather would be expected to be a very small percentage of the total volatile matter.  
4.3 Under the conditions of this test, certain materials in leather, such as protein fiber and chromium tanning salts, may retain moisture. Other materials, such as tannins and oils, may be oxidized. Both of these effects produce negative errors in the moisture determination.  
4.4 The amount of volatile matter (moisture) released by a given leather varies with (a) degree of grinding of the sample, (b) weight of sample taken, (c) temperature and time of the oven drying, (d) shape of the weighing container, and (e) type of oven (gravity versus mechanical convection) used.  
4.5 Because of the above unknown errors, the result of this test is a purely arbitrary value for the moisture content of the sample. It is, therefore, essential that the method be followed exactly in order to obtain reproducible results among laboratories. This is particularly true if other chemical analytical tests being performed on the same sample are reported on the moisture-free basis.
SCOPE
1.1 This test method covers the determination of volatile matter (moisture) in all types of leather.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Mar-2017
• ICS: 59.140.30 - Leather and furs
• Technical Committee: D31 - Leather
• Drafting Committee: D31.06 - Chemical Analysis

Relations

• Replaces: ASTM D3790-79(2012) - Standard Test Method for Volatile Matter (Moisture) of Leather by Oven Drying
• Effective Date: 01-Apr-2017
• Refers: ASTM D2813-03(2008) - Standard Practice for Sampling Leather for Physical and Chemical Tests
• Effective Date: 01-Sep-2008
• Refers: ASTM D2813-03 - Standard Practice for Sampling Leather for Physical and Chemical Tests
• Effective Date: 01-Oct-2003
• Refers: ASTM D2813-97 - Standard Practice for Sampling Leather for Physical and Chemical Tests
• Effective Date: 10-Apr-1997
• Referred By: ASTM D6016-17(2023) - Standard Test Method for Determination of Nitrogen, Water Extractable in Leather
• Effective Date: 01-Apr-2017
• Referred By: ASTM D6017-97(2020)e1 - Standard Test Method for Determination of Magnesium Sulfate (Epsom Salt) in Leather
• Effective Date: 01-Apr-2017
• Referred By: ASTM D3495-10(2023) - Standard Test Method for Hexane Extraction of Leather
• Effective Date: 01-Apr-2017
• Referred By: ASTM D6401-99(2020) - Standard Test Method for Determining Non-Tannins and Tannin in Extracts of Vegetable Tanning Materials
• Effective Date: 01-Apr-2017
• Referred By: ASTM D2807-17a - Standard Test Method for Chromic Oxide in Leather (Perchloric Acid Oxidation)
• Effective Date: 01-Apr-2017

Overview

ASTM D3790-17 is the internationally recognized standard test method for determining the volatile matter (moisture) content in leather by oven drying. Published by ASTM International, this method is widely adopted in the leather industry for quality control and laboratory analysis. The test enables users to obtain an estimate of moisture content in various types of leather, using a consistent oven drying process. Moisture content influences both the chemical properties and performance characteristics of finished leather products, making the results of this method crucial for further chemical analyses reported on a moisture-free basis.

Key Topics

• Moisture Determination: The standard details a method to accurately estimate the volatile matter-primarily water-that can be driven off from leather using controlled heating in a mechanical-convection oven.
• Sample Preparation: Emphasizes strict sample preparation conditions, including grinding, sample weight, oven type, and container design for reliable results.
• Measurement Procedure: Involves heating a ground leather specimen in a mechanical-convection oven at a specified temperature for a set duration, cooling in a desiccator, and performing precise weighings to determine weight loss due to volatile matter.
• Potential Sources of Error: Acknowledges the possible retention of water by some constituents (e.g., protein fiber, chromium tanning salts) and the potential oxidation of others (e.g., tannins, oils), which can introduce negative errors in moisture readings.
• Reproducibility: Stresses the importance of strict adherence to the method to enable reproducibility across laboratories, given the arbitrary nature of the result.
• Limitations: Results are considered arbitrary and are most useful as a basis for correcting other analytical results to a moisture-free basis.

Applications

The ASTM D3790-17 test method is integral to multiple areas within the leather industry and analytical laboratories, such as:

• Quality Control: Leather manufacturers rely on accurate moisture data to ensure consistent product quality and process control, as excessive or insufficient moisture can affect leather durability, finish, and performance.
• Chemical Analysis Support: Moisture results from this test are frequently used to adjust or correct chemical analyses of leather samples, ensuring that results are expressed on a consistent moisture-free basis.
• Research and Development: Laboratories conducting research on new leather treatments, tanning processes, or formulations utilize this method for precise moisture content determination as part of their material assessments.
• Regulatory and Compliance Testing: Meeting international and customer-specific specifications for leather products often requires documentation of moisture content as determined by this ASTM standard.
• Inter-laboratory Comparison: Because the method is highly standardized, it provides a basis for comparing results between different laboratories and for supporting quality assurance programs.

Related Standards

Professionals using ASTM D3790-17 may also reference the following standards for complementary information or additional procedures related to leather testing:

• ASTM D2813 - Practice for Sampling Leather for Physical and Chemical Tests: Provides guidance for obtaining representative leather samples for analysis.
• ISO Leather Moisture Standards: Various ISO standards address leather moisture content and similar analysis methods.
• ASTM Standards for Leather Physical Testing: Explore additional ASTM methods for testing leather properties such as tensile strength, tear resistance, and thickness.

Practical Value

Adhering to ASTM D3790-17 ensures globally recognized, repeatable, and reliable determination of leather moisture content, which is essential for:

• Adjusting chemical composition tests to improve data comparability
• Meeting quality specifications in international trade and manufacturing
• Supporting R&D and material performance evaluations
• Achieving compliance with industry and regulatory standards

By following the outlined procedures, laboratories and manufacturers can minimize variability and uphold the quality and reputation of leather products worldwide.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D3790 − 17
Standard Test Method for
Volatile Matter (Moisture) of Leather by Oven Drying
This standard is issued under the fixed designation D3790; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope 4.2 Materials that are volatile under these conditions, other
thanwater,maybepresentintheleather,althoughtheiramount
1.1 This test method covers the determination of volatile
in any normal leather would be expected to be a very small
matter (moisture) in all types of leather.
percentage of the total volatile matter.
1.2 The values stated in SI units are to be regarded as
4.3 Under the conditions of this test, certain materials in
standard. No other units of measurement are included in this
leather, such as protein fiber and chromium tanning salts, may
standard.
retain moisture. Other materials, such as tannins and oils, may
1.3 This standard does not purport to address all of the
be oxidized. Both of these effects produce negative errors in
safety concerns, if any, associated with its use. It is the
the moisture determination.
responsibility of the user of this standard to establish appro-
4.4 The amount of volatile matter (moisture) released by a
priate safety and health practices and determine the applica-
given leather varies with (a) degree of grinding of the sample,
bility of regulatory limitations prior to use.
(b) weight of sample taken, (c) temperature and time of the
1.4 This international standard was developed in accor-
oven drying, (d) shape of the weighing container, and (e) type
dance with internationally recognized principles on standard-
of oven (gravity versus mechanical convection) used.
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
4.5 Because of the above unknown errors, the result of this
mendations issued by the World Trade Organization Technical
test is a purely arbitrary value for the moisture content of the
Barriers to Trade (TBT) Committee.
sample. It is, therefore, essential that the method be followed
exactly in order to obtain reproducible results among labora-
2. Referenced Documents
tories.This is particularly true if other chemical analytical tests
2.1 ASTM Standards: being performed on the same sample are reported on the
moisture-free basis.
D2813 Practice for Sampling Leather for Physical and
Chemical Tests
5. Apparatus
3. Summary of Test Method
5.1 Weighing Bottle , glass, low-form, cylindrical with a
3.1 The ground leather specimen is heated in a mechanical-
ground-glassstopperofstandardtaper.Thebottleshallhave70
convection oven for 16 h at 100°C, placed in a desiccator,
6 5 mm inside diameter, and 33 6 3 mm overall height.
cooled, and reweighed. The loss in weight represents the
5.2 Oven, mechanical-convection draft capable of setting at
volatile matter.
100°C,withathermoregulatorsystemcapableofholdingoven
temperature within 62 °C of set point.Athermometer accurate
4. Significance and Use
to 60.2 °C should be used to check and monitor the oven set
4.1 Theresultobtainedbythistestisnormallyconsideredto
point.
be the moisture content of the leather sample. This result is
5.3 Balance, capable of weighing up to 100 g with an
used to correct all other chemical tests to a moisture-free basis.
accuracy of 60.001 g.
5.4 Desiccator, any convenient form or size, using any
This test method is under the jurisdiction ofASTM Committee D31 on Leather
normal desiccating agent such as calcium sulfate, calcium
and is the direct responsibility of Subcommittee D31.06 on Chemical Analysis.
Current edition approved April 1, 2017. Published May 2017. Originally
chloride, or silica gel.
approved in 1979. Last previous edition approved in 2012 as D3790 - 79(2012).
DOI: 10.1520/D3790-17.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Weighing bottles that have been found to be satisfactory are the Kimble Glass
Standards volume information, refer to the standard’s Document Summary page on Co. No. 15165 with 71/15 standard-taper caps and are available from most
the ASTM websit
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D3790 − 79 (Reapproved 2012) D3790 − 17
Standard Test Method for
Volatile Matter (Moisture) of Leather by Oven Drying
This standard is issued under the fixed designation D3790; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope
1.1 This test method covers the determination of volatile matter (moisture) in all types of leather.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D2813 Practice for Sampling Leather for Physical and Chemical Tests
E180 Practice for Determining the Precision of ASTM Methods for Analysis and Testing of Industrial and Specialty Chemicals
(Withdrawn 2009)
3. Summary of Test Method
3.1 The ground leather specimen is heated in a mechanical-convection oven for 16 h at 100°C, placed in a desiccator, cooled,
and reweighed. The loss in weight represents the volatile matter.
4. Significance and Use
4.1 The result obtained by this test is normally considered to be the moisture content of the leather sample. This result is used
to correct all other chemical tests to a moisture-free basis.
4.2 Materials that are volatile under these conditions, other than water, may be present in the leather, although their amount in
any normal leather would be expected to be a very small percentage of the total volatile matter.
4.3 Under the conditions of this test, certain materials in leather, such as protein fiber and chromium tanning salts, may retain
moisture. Other materials, such as tannins and oils, may be oxidized. Both of these effects produce negative errors in the moisture
determination.
4.4 The amount of volatile matter (moisture) released by a given leather varies with (a) degree of grinding of the sample, (b)
weight of sample taken, (c) temperature and time of the oven drying, (d) shape of the weighing container, and (e) type of oven
(gravity versus mechanical convection) used.
4.5 Because of the above unknown errors, the result of this test is a purely arbitrary value for the moisture content of the sample.
It is, therefore, essential that the method be followed exactly in order to obtain reproducible results among laboratories. This is
particularly true if other chemical analytical tests being performed on the same sample are reported on the moisture-free basis.
This test method is under the jurisdiction of ASTM Committee D31 on Leather and is the direct responsibility of Subcommittee D31.06 on Chemical Analysis.
Current edition approved April 1, 2012April 1, 2017. Published April 2012May 2017. Originally approved in 1979. Last previous edition approved in 20062012 as
ε1
D3790 - 79(2006)(2012). . DOI: 10.1520/D3790-79R12.10.1520/D3790-17.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D3790 − 17
5. Apparatus
5.1 Weighing Bottle , glass, low-form, cylindrical with a ground-glass stopper of standard taper. The bottle shall have 70 6 5
mm inside diameter, and 33 6 3 mm overall height.
5.2 Oven, mechanical-convection draft capable of setting at 100°C, 100 °C, with a thermoregulator system capable of holding
oven temperature within 6 2°C62 °C of set point. A thermometer accurate to 60.2°C 60.2 °C should be used to check and
monitor the oven set point.
5.3 Balance, capable of weighing up to 100 g with an accuracy of 60.001 g.
5.4 Desiccator, any convenient form or size, using any n
...