ISO INTERNATIONAL STANDARD 105-A05 First edition 1996-04-01 Textiles - Tests for colour fastness - Part A05: Instrumental assessment of change in colour for determination of grey scale rating Textiles - Essais de solidité des teintures Partie A05: Evaluation instrumentale de la degradation pour la détermination du degre de I'échelle de gris ISO Reference number ISO 105-A05:1996(E) IS0105-A05:1996(E) Foreword ISo (the International Organization for Standardization) is a worldwide 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. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International a vote. International Standard isO105-A05waspreparedbyTechnical Committee ISO/TC38,Textiles,SubcommitteeC1,Testsforcolouredtextilesand colorants. Is0 105was previously published in thirteen"parts",each designated by These sections arenowbeingrepublished as separatedocuments,them- nations. A complete list of these parts is given in ISO 105-A01. ISO 1996 or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. International Organization for Standardization Casc Postale 56·CH-1211Gcncvc20·Switzcrland Printed in Switzerland i INTERNATIONALSTANDARDISO ISO 105-A05:1996(E) Textiles - Tests for colour fastness Part A05: Instrumental assessment of change in colour for determination of grey scale rating 1 Scope This part of iso 105 specifies an instrumental method for assessing the change in colour of a test specimen in comparison to an identical untreated reference, and the calculations undertaken to convert the instrumental measurements into a grey scale rating. This method is intended as an alternative to the many national methods for visual evaluation of the effect of a colour fastness test on any textile material. NOTE1 There may be a difference between instrumental and visual assessments of specimens due to fluorescence, and/or other factors. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this part of IsO 105. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this part of iso 105 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. IsO105-J03:1995.Textiles-Tests for colour fastness-Part J03:Calculation of colourdifferences. CIE Publication No.5.2, Colorimetry, 2nd ed., 1986.1) 3 Principle The colour of the specimen which has been subjected to the colour fastness test and the colour of an identical hab are determined for both specimens, and the CIELAB differences AL', ACab and Hab are calculated and con- 1) Available from the CIE Central Bureau, Kegelgasse 27, A-1030 Vienna, Austria.