1、BSI Standards PublicationBS ISO 5631-1:2015Paper and board Determination of colour bydiffuse reflectancePart 1: Indoor daylight conditions (C/2)BS ISO 5631-1:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 5631-1:2015.It supersedes BS ISO 5631-1:2009 which
2、 is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee PAI/11, Methods of test for paper, board and pulps.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessary
3、provisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 86897 9ICS 85.060Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was publishe
4、d under the authority of theStandards Policy and Strategy Committee on 30 November 2015.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS ISO 5631-1:2015 ISO 2015Paper and board Determination of colour by diffuse reflectance Part 1: Indoor daylight conditions (C/2)Papier e
5、t carton Dtermination de la couleur par rflectance diffuse Partie 1: Conditions dclairage intrieur de jour (C/2)INTERNATIONAL STANDARDISO5631-1Second edition2015-11-01Reference numberISO 5631-1:2015(E)BS ISO 5631-1:2015ISO 5631-1:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO
6、 2015, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permissi
7、on. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 5631-1:2015ISO 5631-1:
8、2015(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Terms and definitions . 14 Principle 35 Apparatus . 35.1 Reflectometer . 36 Sampling and conditioning 47 Preparation of test pieces . 48 Procedure. 49 Calculation 49.1 CIE tristimulus values . 49.2 CIELAB coordinates 59.3 Dispersio
9、n of the results . 510 Expression of results 611 Precision . 612 Test report . 6Annex A (normative) Spectral characteristics of reflectometers for determining tristimulus values 7Bibliography .13 ISO 2015 All rights reserved iiiContents PageBS ISO 5631-1:2015ISO 5631-1:2015(E)ForewordISO (the Intern
10、ational 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 b
11、een 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 sta
12、ndardization.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 accord
13、ance 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
14、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 endors
15、ement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committee responsi
16、ble for this document is ISO/TC 6, Paper, board and pulps.This second edition cancels and replaces the first edition (ISO 5631-1:2009). The major change is to allow for calculations using ASTM E308 for instruments that have bandpass correction and still maintain the procedure for instruments without
17、 bandpass correction.ISO 5631 consists of the following parts, under the general title Paper and board Determination of colour by diffuse reflectance: Part 1: Indoor daylight conditions (C/2) Part 2: Outdoor daylight conditions (D65/10) Part 3: Indoor illumination conditions (D50/2)iv ISO 2015 All r
18、ights reservedBS ISO 5631-1:2015ISO 5631-1:2015(E)IntroductionThe colour of an object can be uniquely characterized by means of a triplet of colour coordinates such as the CIE tristimulus values or the CIELAB 1976 L*, a*, b* coordinates for a specified CIE illuminant and CIE standard observer.Apart
19、from the optical properties of the sample, the values of such coordinates depend upon the conditions of measurement, particularly the spectral and geometric characteristics of the instrument used. This part of ISO 5631 should therefore be read in conjunction with ISO 2469.This part of ISO 5631 descr
20、ibes the measurement and description of colour in terms of the CIE illuminant C and the CIE 1931 (2) standard observer. The other parts of this International Standard describe measurements and calculations carried out in an analogous manner using either the CIE standard illuminant D65 and the CIE 19
21、64 (10) standard observer or the CIE illuminant D50 and the CIE 1931 (2) standard observer.The choice of illuminant conditions is important when determining the colour coordinates of white papers containing a fluorescent whitening agent. In ISO 5631-2, the UV content of the illumination is much high
22、er, approximating UV levels encountered in outdoor viewing conditions.ISO 5631-3 describes the measurement and description of colour in terms of the CIE illuminant D50 and the CIE 1931 (2) standard observer. This method is especially applicable to graphic arts situations since these illuminant/obser
23、ver conditions are used within the graphic arts industry. ISO 2015 All rights reserved vBS ISO 5631-1:2015BS ISO 5631-1:2015Paper and board Determination of colour by diffuse reflectance Part 1: Indoor daylight conditions (C/2)1 ScopeThis part of ISO 5631 specifies a method for measuring the colour
24、of paper and board by the diffuse reflectance method with the elimination of specular gloss.This part of ISO 5631 is not applicable to coloured papers or boards which incorporate fluorescent dyes or pigments. It may be used to determine the colour of papers or boards which contain fluorescent whiten
25、ing agents provided the UV content of the illumination on the test piece has been adjusted to conform to that in the CIE illuminant C, using a fluorescent reference standard that fulfils the requirements for international fluorescent reference standards of level 3 (IR3) as prescribed by ISO 2469 wit
26、h an assigned ISO brightness value (C/2) provided by an authorized laboratory, as described in ISO 2470-1.2 Normative referencesThe following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the
27、 latest edition of the referenced document (including any amendments) applies.ISO 186, Paper and board Sampling to determine average qualityISO 2469, Paper, board and pulps Measurement of diffuse radiance factor (diffuse reflectance factor)ISO 2470-1, Paper, board and pulps Measurement of diffuse bl
28、ue reflectance factor Part 1: Indoor daylight conditions (ISO brightness)ASTM E308, Standard Practice for Computing the Colors of Objects by Using the CIE SystemCIE Publication 15:2004, Colorimetry, 3rd ed3 Terms and definitionsFor the purposes of this document, the following terms and definitions a
29、pply.3.1radiance factorratio of the radiance of a surface element of a body in the direction delimited by a given cone, with its apex at the surface element, to that of the perfect reflecting diffuser under the same conditions of illuminationNote 1 to entry: For fluorescent (luminescent) materials,
30、the total radiance factor, , is the sum of two portions, the reflected radiance factor, R, and the luminescent radiance factor, L, so that = R+ L.For non-fluorescent materials, the reflected radiance factor, R, is numerically equal to the reflectance factor, R.INTERNATIONAL STANDARD ISO 5631-1:2015(
31、E) ISO 2015 All rights reserved 1BS ISO 5631-1:2015ISO 5631-1:2015(E)3.2intrinsic radiance factorradiance factor of a layer or pad of material thick enough to be opaque, such that increasing the thickness of the pad by doubling the number of sheets results in no change in the measured radiance facto
32、rNote 1 to entry: The intrinsic radiance factor is often expressed as a percentage.3.3reflectance factorRratio of the radiation reflected by a surface element of a body in the direction delimited by a given cone, with its apex at the surface element to that of the perfect reflecting diffuser under t
33、he same conditions of illuminationNote 1 to entry: The ratio is often expressed as a percentage.Note 2 to entry: The reflectance factor is influenced by the backing if the body is translucent.3.4intrinsic reflectance factorRreflectance factor of a layer or pad of material thick enough to be opaque,
34、such that increasing the thickness of the pad by doubling the number of sheets results in no change in the measured reflectance factorNote 1 to entry: The reflectance factor of a non-opaque sheet is dependent on the background and is not a material property.3.5tristimulus valuesX, Y, Zamount of the
35、three reference colour stimuli, in a given chromatic system, required to match the stimulus consideredNote 1 to entry: In this part of ISO 5631, the CIE illuminant C and the CIE 1931 (2) standard observer are used to define the trichromatic system.Note 2 to entry: No subscript is applied to conform
36、to the CIE convention that tristimulus values have no subscript when the CIE 1931 (2) standard observer is used the subscript 10 is applied for tristimulus values that are obtained using the CIE 1964 (10) standard observer.3.6CIELAB colour spacethree-dimensional, approximately uniform colour space,
37、produced by plotting, in rectangular coordinates L*, a*, b*, quantities defined by the formulae given in Clause 9Note 1 to entry: The quantity, L*, is a measure of the lightness of the test piece, where L* = 0 corresponds to black and L* = 100 is defined by the perfect reflecting diffuser. Visually,
38、 the quantities a* and b* represent respectively the red-green and yellow-blue axes in colour space, such that+a* is a measure of the degree of redness of the test piece,a* is a measure of the degree of greenness of the test piece,+b* is a measure of the degree of yellowness of the test piece, andb*
39、 is a measure of the degree of blueness of the test piece.If both a* and b* are equal to zero, the test piece is achromatic.2 ISO 2015 All rights reservedBS ISO 5631-1:2015ISO 5631-1:2015(E)4 PrincipleThe light reflected from a sample under specified conditions is analysed either by a tristimulus-fi
40、lter colourimeter or by an abridged spectrophotometer, and the colour coordinates are then calculated for C/2 conditions.5 Apparatus5.1 Reflectometer5.1.1 Reflectometer, having the geometric, spectral and photometric characteristics described in ISO 2469, and calibrated in accordance with the provis
41、ions of ISO 2469.If materials containing fluorescent whitening agents are to be measured, the reflectometer shall be equipped with a radiation source having an adequate UV content control, adjusted to a UV condition corresponding to the C illuminant by the use of a reference standard, as described i
42、n ISO 2470-1.5.1.2 In the case of a filter reflectometer, a set of filters that, in conjunction with the optical characteristics of the basic instrument, give overall responses equivalent to the CIE tristimulus values X, Y and Z of the CIE 1931 standard colourimetric system of the test piece evaluat
43、ed for the CIE illuminant C.In the case of a filter reflectometer, the radiation falling upon the test piece shall have a UV content corresponding to that of the CIE illuminant C.5.1.3 In the case of an abridged spectrophotometer, a function that permits calculation of the CIE tristimulus values X,
44、Y and Z of the CIE 1931 standard colourimetric system of the test piece evaluated for the CIE illuminant C using the weighting functions given in Annex A where the Tables A.1 and A.2 are used for instruments without bandpass correction and Tables A.3 and A.4 are used for instruments with bandpass co
45、rrection.In the case of an abridged spectrophotometer, the instrument shall have an adjustable filter with a cut-off wavelength of 395 nm or some other equivalent system, and this filter shall be adjusted or the system shall be calibrated with the help of the fluorescent reference standard (5.2.2),
46、so that the UV content of the illumination falling upon the sample corresponds to that of the CIE illuminant C.5.2 Reference standards, for calibration of the instrument and the working standards and used frequently enough to ensure satisfactory calibration and UV adjustment.5.2.1 Non-fluorescent re
47、ference standard, for photometric calibration, issued by an authorized laboratory in accordance with the provisions of ISO 2469.5.2.2 Fluorescent reference standard, for use in adjusting the UV content of the radiation incident upon the sample, having an ISO brightness value assigned by an authorize
48、d laboratory, as prescribed in ISO 2470-1.5.3 Working standards, calibrated frequently enough to ensure that satisfactory calibration is maintained.5.3.1 Two plates of flat opal glass, made of ceramic or other suitable material, cleaned and calibrated as described in ISO 2469.NOTE In some instrument
49、s, the function of the primary working standard can be taken over by a built-in internal standard.5.3.2 A stable plastic or other tablet, incorporating a fluorescent whitening agent. ISO 2015 All rights reserved 3BS ISO 5631-1:2015ISO 5631-1:2015(E)5.4 Black cavity, having a reflectance factor which does not differ from its nominal value by more than 0,2 % at all wavelengths. The black cavity should be stored upside down in a dust-free environment or with a protective cover.NOTE 1 The reflectance level
