ISO INTERNATIONAL STANDARD 105-A02 Fourth edition 1993-09-01 Textiles - Tests for colour fastness Part A02: Grey scale for assessing change in colour Textiles - Essais de solidité des teintures - Partie Ao2: Echelle de gris pour I'évaluation des dégradations ISO KX Reference number ISO 105-A02:1993(E) IS0 105-A02:1993(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 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. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International a vote. ISO/TC 38, Textiles, Sub-Committee SC 1, Tests for coloured textiles and colorants. Thisfourthedition and replaces third edition cancels the (ISO 105-A02:1987), of which it constitutes a minor revision. IS0 105 was previously published in thirteen "parts", each designated by Each part contained a series of "sections", each designated by the re spective part letter and by a two-digit serial number (e.g. "Section A01"). These sections are now being republished as separate documents, them- nations. A complete list of these parts is given in ISO 105-A01. ISO1993 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without per- mission in writing from the publisher. International Organization for Standardization Case Postale 56 · CH-1211 Geneve 20 · Switzerland Printed in Switzerland ii INTERNATIONAL STANDARD ISO 105-A02:1993(E) Textiles -- Tests for colour fastness Part A02: Grey scale for assessing change in colour Scope 2.4 The second member of each pair shall be such 1 that the colour difference between it and the adjacent first member is as follows: This part of ISO 105 describes the grey scale for de- termining changes in colour of textiles in colour fast- ness tests, and its use. A precise colorimetric Fastness CIELAB differ- Tolerance specification of the scale is given as a permanent ence grade record against which newly prepared working stan- 5 0 0,2 dards and standards that may have changed can be (4-5) 0,8 ± 0,2 compared. 1,7 4 ± 0,3 2,5 (3-4) ± 0,35 3 3,4 Principle ± 0,4 2 4,8 (2-3) ± 0,5 2 6,8 ± 0,6 2.1 The essential, or 5-step, scale consists of five (1-2) 9,6 ± 0.7 pairs of non-glossy grey colour chips (or swatches of 13,6 ± 1,0 grey cloth), which' illustrate the perceived colour dif. ferences corresponding to fastness ratings 5, 4, 3, 2 (Bracketed values apply only to the 9-step scale.) and 1. This essential scale may be augmented by the provision of similar chips or swatches illustrating the perceived colour differences corresponding to the half-step fastness ratings 4-5, 3-4, 2-3 and i-2, such 2.5 Use of the scale. Place a piece of the original scales being termed 9-step scales. The first member textile and the tested specimen of it side by side in of each pair is neutral grey in colour and the second the same plane and oriented in the same direction. member of the pair illustrating fastness rating 5 is Place the grey scale nearby in the same plane. The identical with the first member. The second members surrounding field should be neutral grey colour ap- of the remaining pairs are increasingly lighter in colour proximately midway between that illustrating grade 1 so that each pair illustrates increasing contrasts or and that illustrating grade 2 of the grey scale for as- perceived colour differences which are defined sessing change in colour (this is approximately co