ASTM D1577-07(2018)

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: D1577 − 07 (Reapproved 2018)
Standard Test Methods for
Linear Density of Textile Fibers
This standard is issued under the fixed designation D1577; 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 priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
1.1 These test methods cover the measurement of mass per
1.6 This international standard was developed in accor-
unit length (linear density) of textile fibers and filaments.
dance with internationally recognized principles on standard-
Direct weighing and vibroscope procedures with modifications
ization established in the Decision on Principles for the
for crimped and uncrimped fibers are included. The options
Development of International Standards, Guides and Recom-
and sections are listed below.
mendations issued by the World Trade Organization Technical
Option Sections
Barriers to Trade (TBT) Committee.
A—Fiber Bundle Weighing 7–15
B—Single-Fiber Weighing 16–23
2. Referenced Documents
C—Vibroscope, General 24–30
2.1 ASTM Standards:
35 and 36
C1—Uncrimped Fibers 31 and 32
D123 Terminology Relating to Textiles
C2—Crimped Fibers 33 and 34
D629 Test Methods for Quantitative Analysis of Textiles
Precision and Bias 37 and 38
D1059 Test Method for Yarn Number Based on Short-
NOTE 1—For linear density of short lengths of yarn, refer to Test
Length Specimens
Method D1059. For cotton linear density, refer to Test Methods D1769
D1282 Test Method for Resistance to Airflow as an Indica-
and D2480. For measurement of wool diameter, refer to Test Methods
tion ofAverage Fiber Diameter of Wool Top, Card Sliver,
D1282, D2130, and D3510.
and Scoured Wool
1.2 The crimp, taper, and cross-sectional shape of the fiber
D1769 Test Method for Linear Density of Cotton Fibers
may influence the linear density measured by single-fiber
(Array Sample) (Withdrawn 1988)
weighing and vibroscope.
D1776/D1776M Practice for Conditioning and Testing Tex-
1.3 These test methods measure the linear density of fibers
tiles
with moisture in equilibrium with the standard atmosphere for
D1907/D1907M Test Method for Linear Density of Yarn
testingtextiles.Thefibermoistureundertheseconditionsisnot
(Yarn Number) by the Skein Method
necessarily the same as the commercial moisture regain for the
D2130 Test Method for Diameter ofWool and OtherAnimal
fibers.
Fibers by Microprojection
D2257 Test Method for Extractable Matter in Textiles
1.4 The values stated in either SI units or inch-pound units
D2258/D2258M Practice for Sampling Yarn for Testing
are to be regarded separately as standard. The values stated in
D2480 Test Method for Maturity Index and Linear Density
each system are not exact equivalents; therefore, each system
of Cotton Fibers by the Causticaire Method (Withdrawn
shall be used independently of the other. Combining values
1992)
from the two systems may result in nonconformance with the
D2904 Practice for Interlaboratory Testing of a Textile Test
specification.
Method that Produces Normally Distributed Data (With-
1.5 This standard does not purport to address all of the
drawn 2008)
safety concerns, if any, associated with its use. It is the
D3333 Practice for Sampling Manufactured Staple Fibers,
responsibility of the user of this standard to establish appro-
Sliver, or Tow for Testing
1 2
These test methods are under the jurisdiction of ASTM Committee D13 on For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Textiles and are the direct responsibility of Subcommittee D13.58 on Yarns and contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Fibers. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved July 1, 2018. Published July 2018. Originally approved the ASTM website.
in 1958. Last previous edition approved in 2012 as D1577 – 07 (2012). DOI: The last approved version of this historical standard is referenced on
10.1520/D1577-07R18. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D1577 − 07 (2018)
D3510 Test Method for Diameter ofWool and OtherAnimal 4.4.1 The accuracy of weighing can be controlled by the
Fibers by Image Analyzer (Withdrawn 1986) number of fibers composing the bundle. However, with short
D4849 Terminology Related to Yarns and Fibers fiber of low linear density the number of fibers to be counted
D5103 Test Method for Length and Length Distribution of becomes prohibitive unless the bundle mass is kept low.
Manufactured Staple Fibers (Single-Fiber Test)
4.5 OptionsAand B are fundamental procedures which are
2.2 ASTM Adjuncts:
used to standardize the vibroscope equipment used in Options
TEX-PAC
C1 and C2.
4.6 Test Method Options B and C are most useful for the
3. Terminology
measurement of linear density of single fibers when further
3.1 For all terminology relating to D13.58, Yarns and
tests upon the same test specimen are required, for example,
Fibers, refer to Terminology D4849.
tension tests and adjustment of the data obtained for the linear
3.1.1 The following terms are relevant to this standard:
density of the test specimen. These options offer advantages in
effective fiber length, fundamental resonant frequency, linear
accuracy and ease of operations over calculation from specific
density for fiber and yarn, tex.
gravity and microscopically measured cross-sectional area.
3.2 For all other terminology related to textiles, refer to
4.7 AdditionalinformationspecifictoOptionCisinSection
Terminology D123.
26.
4. Significance and Use
5. Sampling
4.1 OptionAfor bundle weighing of Test Method D1577 is
5.1 Lot Sampling—As a lot sample for acceptance testing,
used in the trade for acceptance testing of commercial ship-
take at random the number of shipping containers directed in
ments.OptionBforsingle-fiberweighingandOptionCforthe
the applicable material specification or other agreement be-
vibroscope may be used for acceptance testing (see Section
tween the purchaser and supplier, such as an agreement to use
37); however, caution is advised when using Option B or
Practice D3333 or Practice D2258/D2258M, as applicable.
Option C because between-laboratory precision information is
Consider shipping containers to be the primary sampling units.
incomplete. Comparative tests as directed in 4.1.1 may be
NOTE 3—An adequate specification or other agreement between the
advisable.
purchaser or supplier requires taking into account the variability between
4.1.1 In case of dispute arising from differences in reported
shipping units, between packages, ends or other laboratory sampling unit
test results when using Test Method D1577 for acceptance
within a shipping unit if applicable, and within specimens from a single
testing of commercial shipments, the purchaser and the sup-
package, end or other laboratory sampling unit to provide a sampling plan
with a meaningful producer’s risk, consumer’s risk, acceptable quality
plier should conduct comparative tests to determine if there is
level, and limiting quantity level.
a statistical bias between their laboratories. Competent statis-
5.2 Laboratory Sample—As a laboratory sample for accep-
tical assistance is recommended for the investigation of bias.
As a minimum, the two parties should take a group of samples tance testing, take at random from each shipping container in
the lot sample the number of laboratory sampling units as
that are as homogeneous as possible and that are from a lot of
material of the type in question. These samples should then be directed in an applicable material specification or other agree-
ment between purchaser and supplier such as an agreement to
randomly assigned in equal numbers to each laboratory for
testing.Theaverageresultsfromthetwolaboratoriesshouldbe use Practice D3333 or Practice D2258/D2258M, as applicable.
Preferably, the same number of laboratory sampling units are
compared using the appropriate statistical analysis and a
probability level chosen by the two parties before testing is taken from each shipping container in the lot sample. If
differing numbers of laboratory sampling units are to be taken
begun. If a bias is found, either the cause must be found and
corrected or the purchaser and the supplier must agree to from shipping containers in the lot sample, determine at
random which shipping containers are to have each number of
interpret future test results for that material with consideration
laboratory units drawn.
to the known bias.
5.2.1 For Staple Fiber—Take 50-g samples from laboratory
4.2 OptionAfor bundle weighing is generally considered to
sampling units.
be the referee procedure for acceptance testing.
5.2.2 For Sliver (or Top) or Tow—Take a metre (yard) from
4.3 OptionAisnotrecommendedformeasurementoflinear
the leading end which has a clean, uniform appearance.
density of blends of production fibers having different nominal
5.2.3 ForYarns—Prepareatleasta50-m(50-yd)skeinfrom
linear densities.
each package.
4.4 The accuracy of the linear density values obtained by
6. Conditioning
Options A and B is dependent upon the accuracy with which
6.1 Condition the laboratory samples as directed in Practice
the fibers can be cut and weighed.
D1776/D1776M.
NOTE 2—On short staple fiber, an accuracy in cutting of 1.0 % is
difficult to obtain. This problem is further complicated if crimp is present
OPTION A—FIBER BUNDLE WEIGHING
in the fibers.
7. Scope
1 7.1 This test method option covers the measurement of the
PC Programs on floppy disk are available through ASTM. For a 3 ⁄2 in disk
request PCN: 12-429040-18. average linear density of textile fibers by cutting and weighing.
D1577 − 07 (2018)
7.2 This international standard was developed in accor- were taken is more than a value agreed upon between the
dance with internationally recognized principles on standard- purchaser and supplier, continue testing in groups of five
ization established in the Decision on Principles for the specimens from the same laboratory sampling units in the
Development of International Standards, Guides and Recom- container until the standard deviation for all specimens tested
mendations issued by the World Trade Organization Technical for the container is not more than the agreed-to value or stop
Barriers to Trade (TBT) Committee. with a specified number testing by agreement.
11.2 Select tufts or bundles of fibers containing a sufficient
8. Summary of Test Method
number of fibers to weigh between 0.5 and 7.5 mg when cut to
8.1 Average linear density, in tex or denier units, of single
the specified length. If fibers from yarns are to be tested,
fibers in a bundle is calculated from mass and length measure-
carefully remove twist before taking specimens.
ments on the bundle and the number of single fibers in the
NOTE 4—Atuft of fibers less than 50 mm in length and below 1 tex (9
bundle.
denier) in nominal linear density will contain 500 to 1000 fibers. The
numberoflongerorcoarserfibersrequiredinatuftwillbeproportionately
9. Apparatus
fewer.
9.1 Balance, having a capacity of 15 mg and sensitivity of
12. Preparation of Specimens
at least 0.005 mg.
9.2 Metal Template, Die, or Mechanical Cutting Device, 12.1 If linear density of finish-free fiber is requested,
remove the finish after cutting the specimen and before
having a precision of 61 % and designed to permit cutting
fibers of a specified length while under tension sufficient to weighing. Refer to Test Method D1907/D1907M, Test Method
D2257, or the Non-fibrous Material Section of Test Methods
remove crimp.
9.2.1 For fibers less than 50 mm in length, a template or die D629 for procedures on the removal of finish.
25 mm in width for measurements in tex units (22.5 mm in
NOTE 5—Hot-water or hot solvent may cause considerable shrinkage
width for measurements in denier units) has been found
and consequent changes in linear density, and should not be used.
satisfactory.
12.2 The specimens chosen from staple fiber may require
9.2.2 For fibers more than 50 mm in length, a mechanical
combing to align the fibers and remove short ends. Because
cutting device, for example, a cutting board having two clamps
fibers are easily stretched, combing must be done with extra
at a greater distance apart than the selected length and having
care. Comb the specimen as follows:
two central clamps for fixing specimens to the board during
12.2.1 Grip the specimen at one end in suitable clamp or
cutting, each with a side adjacent to the path of one of a pair of
tweezers. Ease the specimen onto the stationary coarse comb
traversing blades positioned the selected length apart. Tem-
needles 3 to 5 mm on the clamp side of the center of the tuft.
plates or dies of the type described in 9.2.1 can be made with
Draw the specimen gently toward the center.
appropriate widths for use on longer fibers.
12.2.2 Lift the specimen off the comb. Replace the speci-
9.3 Weights, for preloading crimped fibers.
men on the needles 3 to 5 mm closer to the clamp than the last
position. Draw the specimen gently to the center as before.
9.4 Forceps or Clamps, having gripping surfaces padded
12.2.3 Continue to comb the specimen as directed in 12.2.2
with fiber board, cork, or rubber, and wide enough to hold a
until the clamp is reached and all unclamped fibers are drawn
bundle of fibers firmly.
to the center.
9.5 Stationary Coarse Comb, approximately 63 mm in
12.2.4 Reverse the specimen. Clamp it in the combed
width and having needles approximately 12.5 mm in length
segment approximately 3 to 5 mm from the uncombed
and spaced 19 needles to the centimetre.
segment, near the center. Comb the other end of the specimen,
9.6 Cathetometer.
progressingfromtiptocenterin3to5mmincrements.Discard
the combings.
10. Verification of Equipment Parameters
12.3 Arrange fibers from filament yarn or tows in parallel
10.1 Determine that the length defined by the templates or
alignment.
the cutting edges of dies and mechanical cutting devices is
correct within 1 % by accurate measurement of these devices
13. Procedure
with a cathetometer.
13.1 Test the specimens in the standard atmosphere for
10.2 Determine that the balance and pretension weights are
testing textiles, which is 21 6 1°C (70 6 2°F) and 65 62%
correct within 60.5 % by comparison with standard weights.
relative humidity.
13.2 Place the bundle of fibers prepared as directed in 12.2
11. Test Specimens
or 12.3 in a cutting device or on a flat cutting surface. Make
11.1 Fromeachlaboratorysamplingunitinacontainer,take
certain the fibers are in parallel alignment.
five specimens at random. If the standard deviation determined
13.3 If crimp is present, remove it by pretensioning the
for the container from which the laboratory sampling units
specimen under a tension determined as directed in X1.1 of the
Appendix.
Combs meeting these requirements may be obtained from theAlfred Suter Co.,
Prell Plaza, Orangeburg, NY 10962. NOTE 6—Upon visual examination, if crimp does not appear to be
D1577 − 07 (2018)
completely removed even at greater pretensioning than the minimum
17. Summary of Test Method Option
determined, note this in the report.
17.1 The length of a single fiber, is measured and the fiber
13.4 Cut the specimen to the selected length using template,
is weighed. The linear density of the fiber is then calculated in
die, or cutting device.
dtex or denier units.
13.5 Weigh the specimen to the nearest 0.005 mg.
18. Apparatus
13.6 Count the number of fibers in the bundle.
18.1 Balance, having a sensitivity of at least 0.0001 mg.
NOTE 7—Counting of fine fibers is facilitated by using some magnifi- 18.2 Forceps.
cation and shuffling the specimen on a short pile surface of contrasting
18.3 Specimen Board, of contrasting-color, and with short
color to separate the fibers.
pile for use in measuring fiber lengths and storing specimens.
14. Calculation
18.4 MeasuringScale,withdivisionsin0.5mmincrements.
14.1 Calculate the average fiber linear density for each
19. Test Specimens
specimentothenearest0.1dtex(0.01denier),usingEq1orEq
19.1 From each laboratory sampling unit, take ten speci-
2:
mens at random. If the standard deviation determined for the
T 5 10000W/~L 3N! (1)
d ten specimens is more than a value agreed upon between the
D 5 9000W/ L 3N (2) purchaser and supplier, continue testing in groups of ten
~ !
specimens from the same laboratory sampling unit until the
where:
standard deviation for all specimens tested is not more than the
T = average fiber linear density, dtex,
agreed-to value or stop testing with a specified number by
D = average fiber linear density, denier,
agreement.
W = mass of bundle specimen, mg,
19.2 If fibers from yarns are to be tested, carefully remove
L = length of bundle specimen, mm, and
twist before taking specimens. Using forceps and grasping the
N = number of fibers in the bundle specimen.
specimens at the ends, gently remove the required number of
14.2 Calculate the mean of the average linear density for
specimens from the laboratory sampling units for testing. In
each laboratory sampling unit and for the lot sample.
some cases, it may be advisable to place the specimens on an
identified short-pile of plush surface for storage until ready to
14.3 If requested, calculate the standard deviation, coeffi-
test. Take care to guard against the tendency to select the more
cient of variation or both.
readily visible, hence coarser, fibers as well as the tendency to
compensate for this by selecting finer fibers.Avoid fibers with
15. Report
sharp bends or apparent damage.
15.1 State that the specimens were tested as directed in Test
Methods D1577, Option A, for linear density by fiber bundle 20. Preparation of Test Specimens
weighing. Describe the material(s) or product(s) sampled,
20.1 If linear density of finish-free fiber is requested,
whether the fibers were crimped or uncrimped, and the method
remove the finish as directed inTest MethodsD1907/D1907M,
of sampling.
D2257, or the Nonfibrous Materials Section of Test Methods
D629. See Note 5.
15.2 Report the following information:
15.2.1 Average linear density of each specimen,
21. Procedure
15.2.2 Average fiber linear density values for each labora-
21.1 Test the specimens in the standard atmosphere for
tory sampling unit and the lot.
testing textiles, that is 21 6 1°C (70 6 2°F) and 65 6 2%
15.2.3 The standard deviation, coefficient of variation, or
relative humidity.
both, if calculated, and
21.2 Cut any filaments to measurable lengths. Measure the
15.2.4 Tension to remove crimp, if used.
length of each fiber to the nearest estimated 0.1 mm using Test
OPTION B—SINGLE-FIBER WEIGHING Method D5103. Record the length.
21.3 Weigh each fiber to the nearest 0.0001 mg. Record the
16. Scope
mass.
16.1 This test method option covers the measurement of the
22. Calculation
linear density of single fibers. This option is not recommended
22.1 Calculate the linear density of each fiber to the nearest
for fibers shorter than 30 mm.
0.1 dtex (0.01 denier), using Eq 1 or Eq 2 with N =1.
16.2 This international standard was developed in accor-
22.2 Calculatetheaveragelineardensityforeachlaboratory
dance with internationally recognized principles on standard-
sampling unit and for the lot sample.
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom- 22.3 If requested, calculate the standard deviation, coeffi-
mendations issued by the World Trade Organization Technical cient of variation, or both, for each laboratory sampling unit
Barriers to Trade (TBT) Committee. and for the lot.
D1577 − 07 (2018)
23. Report 26.2 Test instruments arranged to provide data that satisfy
the requirements of Eq 3 and 4 in the manner described in
23.1 State that the specimens were tested as directed in
26.2.1 and 26.2.2 have been found satisfactory in use.
Option B of this test method, for linear density by single-fiber
26.2.1 Type 1—A fiber of known length under known
weighing. Describe the material(s) or product(s) sampled, and
tension is driven at varying frequency until the fundamental
the method of sampling.
resonant frequency of vibration is attained (3, 4, 5, 6).
23.2 Report the following information:
26.2.2 Type 2—A fiber of fixed length is driven at fixed
23.2.1 The linear density of each specimen,
frequency while tension is varied until the fundamental reso-
23.2.2 The average linear density for each laboratory sam-
nant frequency of vibration is attained (7, 8, 9). Instruments of
pling unit and for the lot sample, and
this type have not been marketed commercially.
23.2.3 The standard deviation, the coefficient of variation,
or both, if calculated. 27. Apparatus
27.1 Vibroscope, consisting of the following components:
OPTION C—VIBROSCOPE
27.1.1 A source of sinusoidally alternating energy with
provision for its application to the fiber to cause the fiber to
24. Scope
vibrate transversely.
24.1 These test methods options cover procedures for mea-
27.1.2 Means for applying tension in the range of 3.0 to
suring the linear density of single fibers using the vibroscope.
5.0 mN⁄tex (0.03 to 0.05 g⁄fpden) to the fiber, with an accu-
These options are particularly applicable to staple fibers with
racy of 60.5 %, for example, clips, tabs (with cement), or a
linear density below 10 dtex (9 denier). Option C-1 is for
chain-loading device.
uncrimped fibers and Option C-2 is for crimped fibers.
27.1.3 Means for fixing or defining the test length of the
24.2 This international standard was developed in accor-
fiber to the nearest 0.5 %.
dance with internationally recognized principles on standard- 27.1.4 Means for determining or controlling the fundamen-
ization established in the Decision on Principles for the
tal resonant frequency of vibration developed by the fiber.
Development of International Standards, Guides and Recom- 27.1.5 Means for viewing or otherwise detecting the vibra-
mendations issued by the World Trade Organization Technical
tion of the fiber at its fundamental resonant frequency.
Barriers to Trade (TBT) Committee.
27.2 Cathetometer.
27.3 TabsandAdhesiveCement,formountingspecimenson
25. Summary of Test Method Options
vibroscope, if needed.
25.1 These te
...