4912 International Standard (ISO INTERNATIONAL ORGANIZATION FOR STANDARDIZATION MEXAYHAPOAHAR OPrAHW3AMR HO CTAHAAPTW3AUWM-ORGANISATION INTERNATIONALE DE NORMALISATION Textiles - Cotton fibres - Evaluation of maturity - Microscopic method Textiles -Fibres de coton -Evaluation de la maturite-Methode par microscopie First edition - 1981-06-01 UDC 677.21.017 Ref. No. 1SO 4912-1981 (E) SO4912-1981(E) Descriptors : textiles, cotton fibres, tests, estimation, maturation conditions, sampling, test specimen conditioning. Price based on 8 pages n for Standardization No reproduction or networking permitted without license from IHS Not for Resale Foreword iso (the International Organization for Standardization) is a worldwide federation of national standards institutes (Iso member bodies). The work of developing Inter- national Standards is carried out through Iso technical committees. Every member body interested in a subject for which a technical committee has been set up 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. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISo Council. International Standard ISO 4912 was developed by Technical Committee ISO/TC 38, Textiles, and was circulated to the member bodies in September 1979. Australia Germany,F.R. Romania Belgium Ghana South Africa, Rep. of Brazil Indonesia Spain Bulgaria Italy Sweden Canada Japan Switzerland China Korea,Rep.of Turkey Cyprus New Zealand United Kingdom Denmark Norway USA Egypt, Arab Rep. of Poland Venezuela Finland Portugal Yugoslavia The member bodies of the following countries expressed disapproval of the document on technical grounds : Czechoslovakia France India USSR @ International Organization for Standardization, 1981 Printed in Switzerland Copyright Internaltional Organization for Standardization No reproduction or networking permitted without license from IHS Not for Resale ISO 4912-1981 (E) INTERNATIONALSTANDARD Textiles - Cotton fibres - Evaluation of maturity Microscopic method O Introduction 2 References The term "cotton fibre maturity" is commonly used to signify ISo 139, Textiles - Standard atmospheres for conditioning the extent of fibre wall development. For cottons of similar and testing. length and perimeter, mature cottons (thick walled) generally give fewer neps, are usually more lustrous, and dye deeper in Iso 1130, Textile fibres -- Some methods of sampling for shade than immature (thin walled) cottons. testing. Immature fibres have the following characteristics : 1) they break easily during processing; 3Definitions 2):theyhave a tendencytoformneps; For the purpose of this International Standard, the following 3) they have a tendency for becoming entangled around leaf and trash particles, thus making cleaning more difficult definitionsapply and increasing the amount of fibre removed as waste; 3.1 In the case of option 1, maturity ratio 4) they have an adverse effect on yarn appearance; 5) they do not dye evenly in shade. 3.1.1 dead fibres : Fibres which, after swelling, have a wall thickness of one-fifth or less of the maximum fibre width. Since cotton fibres vary in both wail thickness and perimeter, fibre maturity is best characterized in terms of a ratio or average Dead fibres are present in various forms, from flat ribbons percentage of maturity representing the average degree of wall with no convolutions and little or no fibre wall (figure 2), to thickening, independent of perimeter. These values are derived highly convoluted forms with somewhat greater development fromvisual comparisonsofwallthicknesswithmaximumfibre (figure 1). width, after the fibres have been swollen in 18 % (m/m) sodium hydroxide solution. 3.1.2 normal fibres : Fibres which, after swelling, appear As measurement of the degree of wal