ISO 18068:2014

INTERNATIONAL ISO
STANDARD 18068
First edition
2014-08-15
Cotton fibres — Test method for sugar
content — Spectrophotometry
Fibres de coton — Méthode d’essai pour la teneur en sucre —
Spectrophotométrie
Reference number
ISO 18068:2014(E)
©
ISO 2014

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ISO 18068:2014(E)

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ISO 18068:2014(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Apparatus . 1
6 Reagents . 2
7 Sampling . 3
8 Procedure. 3
8.1 Blank test . 3
8.2 Calibration curve preparation . 3
8.3 Determination of sugar content for test specimens . 4
9 Calculation and expression of the results . 4
10 Test report . 4
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ISO 18068:2014(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
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The committee responsible for this document is ISO/TC 38, Textiles, Subcommittee SC 23, Fibres and
yarns.
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ISO 18068:2014(E)

Introduction
Cotton fibre with normal sugar content might not affect the spinning process. If the sugar content is too
high, it might cause storage mildew and metamorphism. During the spinning process, it might also cause
twining and breakage, and lower yarn quality and production efficiency. Spectrophotometry is used as a
quantitative determination method to detect the total sugar content, and 3,5-dihydroxytoluene-sulfuric
acid solution is used as the colour developer. This International Standard supplies the basic information
for sugar content of cotton fibres.
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INTERNATIONAL STANDARD ISO 18068:2014(E)
Cotton fibres — Test method for sugar content —
Spectrophotometry
WARNING — The use of this International Standard might involve the use of hazardous materials,
operations, and equipment. This International Standard does not purport to address all the safety
risks associated with its use. It is the responsibility of the user of this International Standard
to establish appropriate safety and health practices and determine the applicability of local
regulatory limitations prior to use.
1 Scope
This International Standard specifies a test method to determine the total sugar content in cotton fibres.
Spectrophotometry is used as a quantitative determination method, and 3,5-dihydroxytoluene-sulfuric
acid solution is used as a colour developer. This International Standard is applicable to cotton fibres.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 139:2005, Textiles — Standard atmospheres for conditioning and testing
ISO 1130:1975, Textile fibres — Some methods of samp
...