ASTM D2968-95(2001)

Standard Test Method for Med and Kemp Fibers in Wool and Other Animal Fibers by Microprojection

SCOPE
1.1 This test method covers the determination by microprojection of the percentage of medullated fibers (med and kemp fibers) in wool or other animal fibers such as mohair, cashmere, alpaca, or camel's hair in their various forms.
1.2 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.

General Information

• Status: Historical
• Publication Date: 31-Dec-2000
• ICS: 59.060.10 - Natural fibres
• Technical Committee: D13 - Textiles
• Drafting Committee: D13.13 - Wool and Felt

Relations

• Replaces: ASTM D2968-95 - Standard Test Method for Med and Kemp Fibers in Wool and Other Animal Fibers by Microprojection
• Effective Date: 01-Jan-2001
• Replaced By: ASTM D2968-95(2008) - Standard Test Method for Med and Kemp Fibers in Wool and Other Animal Fibers by Microprojection
• Effective Date: 01-Aug-2008
• Referred By: ASTM D2130-22 - Standard Test Method for Diameter of Wool and Other Animal Fibers by Microprojection
• Effective Date: 01-Jan-2001
• Referred By: ASTM D4845-10(2018) - Standard Terminology Relating to Wool
• Effective Date: 01-Jan-2001

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D 2968 – 95 (Reapproved 2001)
Standard Test Method for
Med and Kemp Fibers in Wool and Other Animal Fibers by
Microprojection
This standard is issued under the fixed designation D 2968; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope as either med fibers or kemp fibers. The observed numbers of
med and kemp fibers are expressed as percentages of the total
1.1 This test method covers the determination by micro-
number of fiber images examined.
projection of the percentage of medullated fibers (med and
kemp fibers) in wool or other animal fibers such as mohair,
5. Significance and Use
cashmere, alpaca, or camel’s hair in their various forms.
5.1 Test Method D 2968 for the determination of med and
1.2 This standard does not purport to address all of the
kempfibersbymicroprojectionmaybeusedfortheacceptance
safety concerns, if any, associated with its use. It is the
testing of commercial shipments of wool and other animal
responsibility of the user of this standard to establish appro-
fibers, but caution is advised since only a few types of animal
priate safety and health practices and determine the applica-
fibers have been subjected to interlaboratory tests to ascertain
bility of regulatory limitations prior to use.
the precision of tests for med and kemp fibers by this test
2. Referenced Documents method. Comparative tests as directed in 5.1.1 may be advis-
able.
2.1 ASTM Standards:
5.1.1 In case of a dispute arising from differences in
D 123 Terminology Relating to Textile Materials
reported test results when using Test Method D 2968 for
D 2130 Test Method for Diameter of Wool and Other
acceptance testing of commercial shipments, the purchaser and
Animal Fibers by Microprojection
the supplier should conduct comparative tests to determine if
3. Terminology
there is a statistical bias between their laboratories. Competent
statistical assistance is recommended for the investigation of
3.1 Definitions—For definitions of other textile terms used
bias.As a minimum, the two parties should take a group of test
in this test method, refer to Terminology D 123.
specimens which are as homogeneous as possible and which
3.2 Definitions of Terms Specific to This Standard:
are from a lot of material of the type in question. The test
3.2.1 kemp fiber, n—a medullated animal fiber in which the
specimens should then be randomly assigned in equal numbers
diameterofthemedullais60 %,ormore,ofthediameterofthe
to each laboratory for testing.The average results from the two
fiber.
laboratories should be compared using Student’s t-test for
3.2.2 med fiber, n—a medullated animal fiber in which the
unpaireddataandanacceptableprobabilitylevelchosenbythe
diameter of the medulla is less than 60% of the diameter of the
two parties before testing is begun. If a bias is found, either its
fiber.
cause must be found and corrected, or the purchaser and the
3.2.3 medulla, n—in mammalian hair fibers, the more or
suppliermustagreetointerpretfuturetestresultsinviewofthe
less continuous cellular marrow inside the cortical layer in
known bias.
most medium and coarse fibers.
5.2 Knowledge of the incidence of med fibers and kemp
3.2.4 medullated fiber, n—an animal fiber that in its original
fibers in wool and other animal fibers is of importance to
state includes a medulla.
manufacturers of woven or knitted fabrics because of the
3.2.5 wool, n—the fibrous covering of the sheep, ovis
apparent dye resistance and light reflectance qualities of these
species.
fibers. This is not to imply that all kemp fibers will resist dye
4. Summary of Test Method
and all med fibers will accept dye normally. In practice, a
proportion of kemp fibers will appear normal after dyeing and
4.1 Themagnifiedimagesofaspecimenoftheanimalfibers
a proportion of med fibers will appear chalky white after
are examined. All medullated fibers are measured and classed
dyeing. From the perspective of visual and aesthetic problems,
medullated fibers having an abnormally large diameter and a
This test method is under the jurisdiction ofASTM Committee D13 onTextiles
high degree of medullation are probably the worst kind.
and is the direct responsibility of Subcommittee D13.13 on Wool and Wool Felt.
Current edition approved Sept. 10, 1995. Published December 1995. Originally
published as D 2968 – 71 T. Last previous edition D 2968 – 89.
Annual Book of ASTM Standards, Vol 07.01.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D 2968
NOTE 1—The contrast between the solid and the hollow portions of the medullated fibers is significantly reduced when the medulla becomes filled with
mounting medium.
FIG. 1 Types of Medulla in Wool and Mohair Fibers
6. Apparatus and Material
m = number of med fibers observed,
k = number of kemp fibers observed, and
6.1 The apparatus and material required in this test method
n = total number of animal fibers observed.
are identical to those specified in Test Method D 2130.
10. Report
7. Sampling
10.1 State that the specimens were tested as directed in Test
7.1 Adequate sampling procedures for loose fibers (grease,
Method D 2968. Describe the material or product sampled and
pulled, and scoured), sliver, top, yarn, and fabric are described
the method used.
in Test Method D 2130.
10.2 Report the following information:
8. Procedure
10.2.1 The med fibers content,
10.2.2 The kemp fibers content, and
8.1 Prepare the test specimens, calibrate the microprojector,
10.2.3 The total number of animal fibers observed.
condition the specimens, and prepare the slides by use of the
heavy-duty cross-section device as directed in Test Method
11. Precision and Bias
D 2130. Have two operators independently prepare at least one
11.1 Interlaboratory Test Data —An interlaboratory test
slide for each test specimen.
wasconductedin1970inwhichthreerandomlydrawnsamples
8.2 Have each of the two operators make observations using
from one lot of mohair top were tested in each of five
the procedure specified in Test Method D 2130, except that
laboratories. Two operators in each laboratory each examined
only medullated fibers need be measured. For such fibers,
500 fibers per sample. The test results for med fibers and kemp
measure the diameter of both th
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