EN ISO 17751-2:2023
(Main)Textiles - Quantitative analysis of cashmere, wool, other specialty animal fibres and their blends - Part 2: Scanning electron microscopy method (ISO 17751-2:2023)
Textiles - Quantitative analysis of cashmere, wool, other specialty animal fibres and their blends - Part 2: Scanning electron microscopy method (ISO 17751-2:2023)
This document specifies a method for the identification, qualitative, and quantitative analysis of cashmere, wool, other speciality animal fibres, and their blends using scanning electron microscopy (SEM).
It is applicable to loose fibres, intermediate products, and final products of cashmere, wool, other speciality animal fibres, and their blends.
Textilien - Quantitative Analyse von Kaschmir, Wolle, anderen speziellen tierischen Fasern und deren Mischungen - Teil2: Rasterelektronenmikroskopie-Verfahren (ISO 17751-2:2023)
Dieses Dokument legt ein Verfahren zur Identifizierung sowie qualitativen und quantitativen Analyse von Kaschmir, Wolle, anderen speziellen tierischen Fasern und deren Mischungen mit dem Rasterelektronenmikroskop (REM) fest.
Es ist anzuwenden für lose Fasern, Halbfertigerzeugnisse und Fertigerzeugnisse aus Kaschmir, Wolle, anderen speziellen tierischen Fasern und deren Mischungen.
Textiles - Analyse quantitative du cachemire, de la laine, d’autres fibres animales spéciales et de leurs mélanges - Partie 2: Méthode par microscopie électronique à balayage (ISO 17751-2:2023)
Le présent document spécifie une méthode pour l'identification et l'analyse, qualitative et quantitative, du cachemire, de la laine et d'autres fibres animales spéciales, ainsi que de leurs mélanges, au moyen de la microscopie électronique à balayage (MO).
Il s'applique aux fibres en vrac, aux produits intermédiaires et aux produits finaux de cachemire, de laine et d'autres fibres animales spéciales, ainsi que de leurs mélanges.
Tekstilije - Kvantitativna analiza kašmirskih, volnenih, drugih specialnih živalskih vlaken in njihovih mešanic - 2. del: Metoda štetja z elektronskim mikroskopom (ISO/FDIS 17751-2:2023)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
oSIST prEN ISO 17751-2:2022
01-oktober-2022
Tekstilije - Kvantitativna analiza kašmirskih, volnenih, drugih specialnih živalskih
vlaken in njihovih mešanic - 2. del: Metoda štetja z elektronskim mikroskopom
(ISO/DIS 17751-2:2022)
Textiles - Quantitative analysis of cashmere, wool, other specialty animal fibres and their
blends - Part 2: Scanning electron microscopy method (ISO/DIS 17751-2:2022)
Textilien - Quantitative Analyse von Kaschmir, Wolle, anderen speziellen tierischen
Fasern und deren Mischungen - Teil2: Rasterelektronenmikroskopie-Verfahren (ISO/DIS
17751-2:2022)
Textiles - Analyse quantitative du cachemire, de la laine, d’autres fibres animales
spéciales et de leurs mélanges - Partie 2: Méthode par microscopie électronique à
balayage (ISO/DIS 17751-2:2022)
Ta slovenski standard je istoveten z: prEN ISO 17751-2
ICS:
59.060.10 Naravna vlakna Natural fibres
oSIST prEN ISO 17751-2:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN ISO 17751-2:2022
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oSIST prEN ISO 17751-2:2022
DRAFT INTERNATIONAL STANDARD
ISO/DIS 17751-2
ISO/TC 38 Secretariat: SAC
Voting begins on: Voting terminates on:
2022-08-25 2022-11-17
Textiles — Quantitative analysis of cashmere, wool, other
specialty animal fibres and their blends —
Part 2:
Scanning electron microscopy method
Partie 2: Méthode par microscopie électronique à balayage
ICS: 59.060.10
This document is circulated as received from the committee secretariat.
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oSIST prEN ISO 17751-2:2022
ISO/DIS 17751-2:2022(E)
DRAFT INTERNATIONAL STANDARD
ISO/DIS 17751-2
ISO/TC 38 Secretariat: SAC
Voting begins on: Voting terminates on:
Textiles — Quantitative analysis of cashmere, wool, other
specialty animal fibres and their blends —
Part 2:
Scanning electron microscopy method
Partie 2: Méthode par microscopie électronique à balayage
ICS: 59.060.10
This document is circulated as received from the committee secretariat.
COPYRIGHT PROTECTED DOCUMENT
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© ISO 2022
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ii
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PROVIDE SUPPORTING DOCUMENTATION. © ISO 2022
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oSIST prEN ISO 17751-2:2022
ISO/DIS 17751-2:2022(E)
Contents Page
Foreword .iv
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Apparatus . 3
6 Reagents and materials . 3
7 Sampling . 3
8 Preparation of test specimen . 3
8.1 Number of test specimen . 3
8.2 Preparation method for test specimen . 3
8.2.1 Loose fibre. 3
8.2.2 Sliver . . 4
8.2.3 Yarn . 5
8.2.4 Woven fabrics . 5
8.2.5 Knitted fabrics . 5
8.3 Coating of the test specimen . 5
9 Test Procedure .5
9.1 General . 5
9.2 Preparation and test on test specimen stub . 5
9.3 Qualitative analysis (purity analysis). 6
9.4 Quantitative analysis . 6
10 Calculation and expression of test result . 6
10.1 Calculation of test result . 6
10.2 Expression of the test result . . 7
10.3 Test report . 7
Annex A (normative) Drawing of the lot sample and the laboratory sample .8
Annex B (informative) Surface morphology of common animal fibres . 9
Annex C (normative) Density of common animal fibres .50
Bibliography .51
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ISO/DIS 17751-2:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/
iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 38, Textiles.
This second edition cancels and replaces the first edition (ISO 17751-2:2016), which has been technically
revised.
The main changes are as follows:
— Clause 2 (Terms and definitions) has been added;
— in 3.1, a note to different types of specialty animal fibres has been added;
— the title of Subclause 7.2 has been changed from “Preparation method for test specimens of various
types of samples” to “Preparation method for test specimens”;
— in 7.2.4.1, missing information on marking of masses of warp and weft yarns and laboratory sample
have been supplemented;
— the title of Subclause 8.1 has been changed from “Test on each test specimen stub” to “Preparation
and test on test specimen stub”;
— the title of Subclause 8.2 and has been changed from “Qualitative analysis(Purity analysis) and
determination of fibre content” to “Qualitative analysis(Purity analysis)”;
— A new Subclause 8.3 and the title “Quantitative analysis” has been added;
— the title of Clause 9 has been changed from “Calculation of test result” to “Calculation and expression
of test result”;
— Subclause 9.1 and the title “Calculation of the test result” has been added;
— Subclause 9.2 and the title “Expression of the test result” and its contents has been added;
— Clause 10 (Test report) and its contents has been added;
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— the property of Annex A has been changed from informative to normative;
— in Annex C, density of some fibres has been modified and the density of coarse rabbit hair has been
added;
— in Annex C, a footnote has been added to both fine rabbit and coarse rabbit;
— two references have been added in the bibliography;
A list of all parts in the ISO 17751 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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ISO/DIS 17751-2:2022(E)
Introduction
Cashmere is a high value specialty animal fibre, but cashmere and other animal wool fibres such as
sheep’s wool, yak, camel etc., exhibit great similarities in their physical and chemical properties, so that
their blends are difficult to distinguish from each other by both mechanical and chemical methods. In
addition, these fibres show similar scale structures. It is very difficult to accurately determine the fibre
content of such fibre blends by current testing means.
Research on the accurate identification of cashmere fibres has been a long undertaking. At present, the
most widely used and reliable techniques include the light microscopy (LM) method and the scanning
electron microscopy (SEM) method. The SEM method shows complementary characteristics to those of
LM method.
— The advantage of LM method is that the internal medullation and pigmentation of fibres can be
observed; the disadvantage is that some subtle surface structures cannot be clearly displayed. A
decolouring process needs to be carried out on dark samples for testing, An improper decolouring
process can affect the judgment of fibre analyst.
— The SEM method shows complementary characteristics to those of LM method, so some types of
fibres need to be identified by scanning electron microscope.
The LM and SEM methods need be used together to identify some difficult-to-identify samples in order
to utilize the advantages of both methods.
It has been proven in practice that the accuracy of a fibre analysis is highly related to the ample
experience, full understanding, and extreme familiarity of the fibre analyst to the surface morphology
of various types of animal fibres. So besides the textual descriptions, several micrographs of different
types of animal fibres are given in Annex B.
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oSIST prEN ISO 17751-2:2022
DRAFT INTERNATIONAL STANDARD ISO/DIS 17751-2:2022(E)
Textiles — Quantitative analysis of cashmere, wool, other
specialty animal fibres and their blends —
Part 2:
Scanning electron microscopy method
1 Scope
This part of ISO 17751 specifies a method for the identification, qualitative, and quantitative analysis
of cashmere, wool, other specialty animal fibres, and their blends using scanning electron microscopy
(SEM).
This part of ISO 17751 is applicable to loose fibres, intermediate products, and final products of
cashmere, wool, other specialty animal fibres, and their blends.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
specialty animal fibre
any type of keratin fibre taken from specialty animals(hairs) other than sheep
Note 1 to entry: Specialty animal fibres include cashmere, camel hair, yak, mohair, angora or rabbit, alpaca, etc.
3.2
scanning electron microscope
intermediate type of microscopic morphology observation instrument between transmitted electron
microscope and light microscopewhich use a focused beam of high-energy electrons to generate a
variety of physical information signals
Note 1 to entry: The principle consists of scanning a primary focused electron beam over a whole area of interest
on the surface of solid test specimen, and the signal derived from which is then received, amplified and displayed
in images for full observation of surface area topography of the test specimen.
Note 2 to entry: The signals obtained by a scanning electron microscope are, e.g., secondary electrons, Auger
electrons, characteristic X-ray etc.
1
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3.3
secondary electron
low-energy extra-nuclear electron released from and by ionization of a metal atom in the 5 nm to 10 nm
scanned region of metal layer less than 10 nm thick nearest to the outermost meta-coated surface of a
test specimen under impact of the focused primary electron beam of energy in units of tens of keV
Note 1 to entry: Being surface sensitive because of the small mean free path of the electron to escape from deep
within the test specimen and, therefore the signal of which produces the highest-resolution morphological
images of the coated surface.
3.4
scale
cuticle covering the surface of animal fibres
3.5
scale frequency
number of scales along the fibre axis per unit length
3.6
scale height
height of the cuticle at the scale’s distal edge
3.7
fibre surface morphology
sum of the physical properties/attributes characterizing the fibre surface
EXAMPLE The fibre surface morphology includes scale frequency, scale height, patterns of scale edge, scale
surface smoothness, fibre evenness along its axis, transparency under light microscope etc.
3.8
lot sample
portion representative of the same type and same lot of material drawn according to the requirements
from which it is taken
3.9
laboratory sample
portion drawn from a lot sample according to the requirements to prepare test specimens
3.10
test specimen
portion taken from fibre snippets randomly cut from a laboratory sample for measurement purposes
4 Principle
A longitudinal view image of fibre snippets representative of a test specimen coated with a thin layer
of gold and/or other metals is produced by a scanning electron microscope through scanning the side
surface of the test specimen with a focused incident beam of high-energy electrons, detecting signals
of secondary electrons emitted by the gold atoms excited when hit by the incident electron beam,
and combining the beam position with the detected signals which contain information on surface
topography of the test specimen.
All fibre types found in the test specimen are identified by comparing them with known fibre surface
morphologies for different types of animal fibres.
For each fibre type, the number and diameter of fibre snippets are counted and measured. The mass
fraction is calculated from the data for the number of fibre snippets counted, mean value, and standard
deviation of the snippet diameter and the true density of each fibre type.
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5 Apparatus
5.1 Scanning electron microscope, comprised of a vacuum system, electronic optical system, signal
collecting and imaging system, display system, and measurement software.
5.2 Sputter coater with a gold and/or other metal cathode.
5.3 Microtome or double blades.
6 Reagents and materials
6.1 Glass tube, 10 mm to 15 mm in diameter.
6.2 Stainless-steel rod, approximately 1 mm in diameter.
6.3 Glass plate, measuring approximately 150 mm x 150 mm.
6.4 Double-sided adhesive tape.
6.5 Tweezers, scissors.
6.6 Test specimen stub, aluminium or brass, 13 mm in diameter.
6.7 Razor blade.
6.8 Acetone, analytical grade.
6.9 Ethyl acetone, analytical grade.
7 Sampling
Drawing the lot and laboratory samples in accordance with sampling method specified in Annex A.
8 Preparation of test specimen
8.1 Number of test specimen
Prepare a set of test specimen composed of 5 test specimen stubs. Fibre snippets on the test specimen
stubs shall be sufficient to ensure at least 1 000 fibres snippets are examined.
8.2 Preparation method for test specimen
8.2.1 Loose fibre
8.2.1.1 Place the laboratory sample flat on the test table, pick up approximately 500 mg of fibres
randomly on not less than 20 spots with tweezers from the top and bottom sides of the sample. Blend
them homogeneously, and divide them into 3 equal portions. Sort those drawn fibres into basically
parallel fibre bundles.
8.2.1.2 Cut each bundle in the middle with a microtome and razor blade or double blades to get
approximately 0,4 mm long fibre snippets. Cut only once in each of the fibre bundles.
3
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8.2.1.3 Collect all fibre snippets in the glass tube and suspend them in 1 ml to 2 ml acetone or ethyl
acetate by stirring the mixture with a stainless-steel rod. Pour the suspension onto a glass plate to
ensure that the fibre snippets are uniformly distributed on a spot of approximately 10 cm in diameter
on the glass plate, as shown in Figure 1.
8.2.1.4 Press the double-sided adhesive tape on the mounting stubs and use a razor blade to trim
the adhesive tape away from around the mounting stubs. After all the acetone or ethyl acetate in the
fibre snippets suspension has evaporated, press the mounting stubs with the adhesive tape end onto
the glass plate at the positions shown in Figure 2. Transfer the uniformly mixed fibre snippets to the
adhesive tape on the test specimen stub.
Key
1 glass plate
2 fibre snippets
Figure 1 — Fibre suspension on glass plate
Key
1 test specimen stub
Figure 2 — Positions of test specimen stubs
8.2.1.5 If the fibre snippets have aggregated after the evaporation of the acetone or ethyl acetate,
they shall be recollected by scraping them off the glass plate with a razor blade and repeat operation
procedures 8.2.1.3 and 8.2.1.4.
8.2.2 Sliver
8.2.2.1 Cut the laboratory sliver sample into three sections. Take out an appropriate amount of the
fibre bundle in the longitudinal direction from each sliver section.
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8.2.2.2 Cut in the middle of each fibre bundle to obtain approximately 0,4 mm long fibre snippets
with a microtome and razor blade. Cut only once in each fibre bundle.
8.2.2.3 Other operation procedures are the same as described in 8.2.1.3 to 8.2.1.5.
8.2.3 Yarn
8.2.3.1 Divide the laboratory sample into three equal portions.
8.2.3.2 Cut each portion in the middle with a microtome and razor blade to obtain approximately
0,4 mm long fibre snippets. Cut only once in each yarn portion.
8.2.3.3 Other operation procedures are the same as described in 8.2.1.3 to 8.2.1.5.
8.2.4 Woven fabrics
8.2.4.1 If the warp and weft yarn share the same composition, all the yarn segments unravelled from
a square sample of a complete pattern may be cut to obtain an appropriate test specimen. For those
fabric samples composed of different compositions of warp and weft yarns, unravel the warp and weft
yarns separately, weigh them and record their masses as M and Mw respectively. If the fabrics have
T
a definite repetition in the pattern, unravel at least the integral multiple of a complete pattern. The
unravelled warp and weft yarn bundles are kept as warp and weft yarn samples respectively as the
laboratory sample.
8.2.4.2 Cut once from the parallel yarn portion in the middle with a microtome or razor blade to
obtain approximately 0,4 mm long fibre snippets. Cut only once in each yarn segments.
8.2.4.3 Other operation procedures are the same as described in 8.2.1.3 to 8.2.1.5.
8.2.5 Knitted fabrics
8.2.5.1 Unravel at least 25 yarn segments from the laboratory sample for woollen knitted fabrics.
Unravel at least 50 yarn segments for worsted knitted fabrics. Cut each yarn portion in the middle to
obtain approximately 0,4 mm long fibre snippets. Cut only once in each yarn portion.
8.2.5.2 Other operation procedures are the same as described in 8.2.1.3 to 8.2.1.5.
8.3 Coating of the test specimen
Use the sputter coater to apply a thin layer of gold and/or other metals to the test specimen on test
specimen stub.
9 Test Procedure
9.1 General
When possible, it is recommended to carry out the analysis of the two test specimens independently by
two operators.
9.2 Preparation and test on test specimen stub
9.2.1 Place a stub with the test specimen into the test chamber of the SEM. First, view the selected
stub at a lower magnification (for example, at ×10). Then, selecting from an area near the upper left
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edge of the stub on the monitor, set the magnification to ×1000, scan the stub and observe the fibres.
Identify the fibre types according to characteristics of the fibre morphologies (see details in Annex B) of
cashmere, sheep’s wool and other animal fibres.
9.2.2 Return to the lower magnification after identifying all fibres in the selected area. Choose
another observation area along vertical or horizontal direction, repeat the above operations until
finished, scanning the entire stub before continuing on to analyse fibre snippets on another stub.
9.3 Qualitative analysis (purity analysis)
Examine 150 fibres on the first test specimen stub. The following three conditions may happen.
— Case 1: If only one fibre type is found, examine another 300 fibre snippets on a second stub. If no
fibre of a second type is found, the sample is declared as pure.
— Case 2: If two fibre types are found and the amount of one type is lower than 3% by number (less
than 5 fibres of the second type), it is considered as a minor component. Examine 300 further
snippets from the second stub and calculate the percentage by number of the two types of fibres.
— Case 3: if two or more fibre types are found andthe fibre mixture is considered to be a blend, perform
a quantitative analysis according to 8.3.
9.4 Quantitative analysis
If the sample is found to be a blend, examine 220 further fibres and measure the diameters of
the first 25 fibres of each component identified, (or all fibres of that component, if less than 25) on
each of the remaining four stubs. At least a total of 1 030 fibres shall be identified for a sample and
100 measurements of fibre diameter are made for each component. The mean fibre diameter of each
component is calculated according to diameters measured for the 100 fibres. If the total amount of each
component is less than 100, calculate the mean fibre diameter according to the actual number of that
fibre component.
This diameter is measured in vacuum condition and is not comparable to diameter measured by other
instruments. So the value shall only be used for calculation of fibre content of each component in
Clause 10.
10 Calculation and expression of test result
10.1 Calculation of test result
10.1.1 Calculate the mass fraction of each component with Formula (1). Density of various types of
animal fibres is specified in Annex C.
22
ND +S ρ
()
ii ii
w = ×100 (1)
i
22
∑+ND()S ρ
()
ii ii
where
w is the mass fraction of the component, %;
i
N is the number of fibres counted for the component;
i
S is the standard deviation of mean fibre diameter of the component, in micrometres (µm);
i
D is the mean fibre diameter of t
...
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