ASTM D3790-79(2006)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:D3790–79(Reapproved2006)
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 Department of Defense.
1. Scope be oxidized. Both of these effects produce negative errors in
the moisture determination.
1.1 This test method covers the determination of volatile
4.4 The amount of volatile matter (moisture) released by a
matter (moisture) in all types of leather.
given leather varies with (a) degree of grinding of the sample,
1.2 This standard does not purport to address all of the
(b) weight of sample taken, (c) temperature and time of the
safety concerns, if any, associated with its use. It is the
oven drying, (d) shape of the weighing container, and (e) type
responsibility of the user of this standard to establish appro-
of oven (gravity versus mechanical convection) used.
priate safety and health practices and determine the applica-
4.5 Because of the above unknown errors, the result of this
bility of regulatory limitations prior to use.
test is a purely arbitrary value for the moisture content of the
2. Referenced Documents sample. It is, therefore, essential that the method be followed
exactly in order to obtain reproducible results among labora-
2.1 ASTM Standards:
tories.This is particularly true if other chemical analytical tests
D2813 Practice for Sampling Leather for Physical and
being performed on the same sample are reported on the
Chemical Tests
moisture-free basis.
E180 Practice for Determining the Precision of ASTM
Methods for Analysis and Testing of Industrial and Spe-
5. Apparatus
cialty Chemicals
5.1 Weighing Bottle , glass, low-form, cylindrical with a
3. Summary of Test Method
ground-glassstopperofstandardtaper.Thebottleshallhave70
6 5 mm inside diameter, and 33 6 3 mm overall height.
3.1 The ground leather specimen is heated in a mechanical-
5.2 Oven, mechanical-convection draft capable of setting at
convection oven for 16 h at 100°C, placed in a desiccator,
100°C, with a thermoregulator system capable of holding oven
cooled, and reweighed. The loss in weight represents the
temperature within 6 2°C of set point.Athermometer accurate
volatile matter.
to 60.2°C should be used to check and monitor the oven set
4. Significance and Use
point.
5.3 Balance, capable of weighing up to 100 g with an
4.1 Theresultobtainedbythistestisnormallyconsideredto
accuracy of 60.001 g.
be the moisture content of the leather sample. This result is
5.4 Desiccator, any convenient form or size, using any
used to correct all other chemical tests to a moisture-free basis.
normal desiccating agent such as calcium sulfate, calcium
4.2 Materials that are volatile under these conditions, other
chloride, or silica gel.
thanwater,maybepresentintheleather,althoughtheiramount
in any normal leather would be expected to be a very small
6. Sampling
percentage of the total volatile matter.
6.1 TheleathershallbesampledinaccordancewithPractice
4.3 Under the conditions of this test, certain materials in
D2813.
leather, such as protein fiber and chromium tanning salts, may
retain moisture. Other materials, such as tannins and oils, may
7. Procedure
7.1 Insert the empty weighing bottle inside the inverted
stopperedcapandplaceonashelfintheovenat100 62°Cfor
This test method is under the jurisdiction ofASTM Committee D31 on Leather
1 h or more. If the stopper has a handle then the stopper may
and is the direct responsibility of Subcommittee D31.06 on Chemical Analysis.
Current edition approved Oct. 1, 2006. Published November 2006. Originally be placed on the shelf in the oven near the empty weighing
approved in 1979. Last previous edition approved in 2001 as D3790 - 79(2001)
bottle.
DOI: 10.1520/D3790-79R06.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Weighing bottles that have been found to be satisfact
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