1、BSI Standards PublicationBS EN ISO 6271:2015Clear liquids Estimation ofcolour by the platinum-cobaltcolour scaleBS EN ISO 6271:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 6271:2015. It supersedes BS EN ISO 6271-1:2004 and BS EN ISO 6271-2:2004 which
2、 are withdrawn.The UK participation in its preparation was entrusted to Technical Committee STI/3, Paints, media and related products.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provi
3、sions of a contract. Users are responsible for its correct application. The British Standards Institution 2016.Published by BSI Standards Limited 2016ISBN 978 0 580 83752 4 ICS 87.060.20 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was publis
4、hed under the authority of the Standards Policy and Strategy Committee on 31 January 2016.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 6271 December 2015 ICS 87.060.20 Supersedes EN ISO 6271-1:2004, EN ISO 6271-2:2
5、004English Version Clear liquids - Estimation of colour by the platinum-cobalt colour scale (ISO 6271:2015) Liquides clairs - valuation de la couleur au moyen de lchelle platine-cobalt (ISO 6271:2015) Klare Flssigkeiten - Bestimmung der Farbe nach der Platin-Cobalt-Farbskala (ISO 6271:2015) This Eur
6、opean Standard was approved by CEN on 1 November 2015. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
7、concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN membe
8、r into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, Fran
9、ce, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey andUnited Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOM
10、ITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 6271:2015 EBS EN ISO 6271:2015EN ISO 6271:2015 (E) 3 European foreword This document (EN ISO
11、6271:2015) has been prepared by Technical Committee ISO/TC 35 “Paints and varnishes“ in collaboration with Technical Committee CEN/TC 139 “Paints and varnishes” the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of
12、an identical text or by endorsement, at the latest by June 2016, and conflicting national standards shall be withdrawn at the latest by June 2016. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be hel
13、d responsible for identifying any or all such patent rights. This document supersedes EN ISO 6271-1:2004, EN ISO 6271-2:2004. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Bel
14、gium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switz
15、erland, Turkey and the United Kingdom. Endorsement notice The text of ISO 6271:2015 has been approved by CEN as EN ISO 6271:2015 without any modification. BS EN ISO 6271:2015ISO 6271:2015(E)Foreword iv1 Scope . 12 Normative references 13 Principle 14 Apparatus and materials 15 Sampling 26 Procedure.
16、 27 Expression of results 28 Precision . 28.1 General . 28.2 Repeatability limit, r 28.3 Reproducibility limit, R 28.4 Bias 39 Test report . 3Annex A (normative) Platinum-cobalt colour standards . 4Bibliography 6 ISO 2015 All rights reserved iiiContents PageBS EN ISO 6271:2015ISO 6271:2015(E)Forewor
17、dISO (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 which a technical
18、 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 elec
19、trotechnical standardization.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 d
20、rafted in accordance 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
21、rights. Details 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 cons
22、titute an endorsement.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 informationISO 62
23、71 was prepared by Technical Committee ISO/TC 35, Paints and varnishes, Subcommittee SC 10, Test methods for binders for paints and varnishes, in collaboration with ASTM D 01.34, Naval Stores. It has been harmonized with ASTM D 1209-05, Standard Test Method for Color of Clear Liquids (Platinum-Cobal
24、t Scale).This third edition of ISO 6271 cancels and replaces ISO 6271-1:2004 and ISO 6271-2:2004, which have been technically revised. The main changes are:a) both standards have been combined into one standard;b) the spectrophotometric method (formerly described in ISO 6271-2:2004) is the only ones
25、tandardized now;c) the original visual comparison of colours (formerly described in ISO 6271-1:2004) has been deleted,and the description of manufacture of the original platinum-cobalt colour standards has beenmoved to Annex A.iv ISO 2015 All rights reservedBS EN ISO 6271:2015INTERNATIONAL STANDARD
26、ISO 6271:2015(E)Clear liquids Estimation of colour by the platinum-cobalt colour scale1 ScopeThis International Standard specifies a spectrophotometric method for estimating the colour of clear liquids in terms of platinum-cobalt units (Pt-Co units). It is applicable to clear liquids having a colour
27、 characteristic similar to those of the platinum-cobalt colour scale specified in Annex A. For products with colours more intense than the Pt-Co stock solution the method specified in ISO 4630 applies.The spectrophotometric method provides a more precise way of measuring Pt-Co colour than a visual s
28、ample comparison by human eyes.NOTE The term “Pt-Co colour” used here is preferred over the terms “Hazen colour” and “APHA colour”.2 Normative referencesThe following referenced documents, in whole or in part, are normally referenced in this document and are indispensable for its application. For da
29、ted references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 3696, Water for analytical laboratory use Specification and test methodsISO 5725-2, Accuracy (trueness and precision) of measurement methods an
30、d results Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement methodISO 15528, Paints, varnishes and raw materials for paints and varnishes SamplingCIE Publication No. 15:2004, Colorimetry3 PrincipleThe colour of a liquid sample is measured using
31、 an instrument capable of measuring transmitted colour and reporting in Pt-Co colours or in a colour system that can be converted into Pt-Co colours.4 Apparatus and materials4.1 Colour-measuring instrument, spectrophotometer capable of measuring transmitted colour (0/180 geometry) and reporting the
32、results in the Pt-Co colour scale. If such an instrument is not available, one may be used which is capable of measuring transmitted colour and reporting in tristimulus values using standard illuminant C and the 2 observer, described in CIE Publication No. 15:2004.4.2 Absorption cells, 50 mm light p
33、ath length recommended, unless a different path length is specified by the instrument manufacturer or4.3 Glass tubes, 11 mm path length. Glass test tubes designed for a specific instrument may be used. Glass tubes might provide less accuracy in the very low colour range than 50 mm absorption cells a
34、nd should be used only when a decrease in accuracy is tested and considered acceptable. ISO 2015 All rights reserved 1BS EN ISO 6271:2015ISO 6271:2015(E)5 SamplingTake a representative sample of the product to be tested, as described in ISO 15528.6 ProcedureBaseline calibration of the instrument sha
35、ll be performed following the instrument manufacturers recommendations.If the material shows any visual haziness, remove the haze e.g. by filtration, centrifugation, heating, ultrasonic treatment or any other suitable means (see Note).If the haziness cannot be removed, the measured value will be unr
36、eliable.Then, using the same type of glass tube or absorption cell as used for the baseline calibration, fill the glass tube or absorption cell with the product. Take care not to touch the measurement area of the glass tube or absorption cell.Avoid creating air bubbles when filling the glass tube or
37、 absorption cell. If air bubbles are formed and remain trapped, remove them by heating, vacuum, ultrasonic treatment or any other suitable means (see Note).NOTE Some sample pre-treatments can change the colour.Insert the glass tube or absorption cell in the instrument and measure the Pt-Co colour, f
38、ollowing the instrument manufacturers recommended procedure.Regular checks as per the instrument manufacturers recommendations should be carried out. These will normally be in the form of checks with certified reference materials.7 Expression of resultsReport the colour in Pt-Co colour units as give
39、n by the instrument.8 Precision8.1 GeneralThe precision of the test method was determined by inter-laboratory testing in accordance with ISO 5725-2.Four different materials were tested by 143 laboratories.8.2 Repeatability limit, rThe repeatability limit r is the value below which the absolute diffe
40、rence between two single test results, each the mean of duplicates, obtained on identical material by one operator in one laboratory within a short interval of time using the standardized test method can be expected to lie with a probability of 95 %.The repeatability for three repeated measurements,
41、 made in accordance with this International Standard and expressed as the repeatability limit r, is 1,9 %, relative to the mean.8.3 Reproducibility limit, RThe reproducibility limit R is the value below which the absolute difference between two test results, each the mean of duplicates, obtained on
42、identical material by operators in different laboratories using the standardized test method can be expected to lie with a probability of 95 %.2 ISO 2015 All rights reservedBS EN ISO 6271:2015ISO 6271:2015(E)The reproducibility for three repeated measurements, made in accordance with this Internatio
43、nal Standard and expressed as the reproducibility limit R, is 4,8 %, relative to the mean.8.4 BiasSince there is no accepted reference material suitable for determining the bias of the procedure in this test method, bias has not been determined.9 Test reportThe test report shall contain at least the
44、 following information:a) all details necessary to identify the product examined;b) a reference to this International Standard (ISO 6271);c) any type of pretreatment of the test sample;d) the result of the test as indicated in Clause 7;e) any deviation from the test method specified;f) any unusual f
45、eatures (anomalies) observed during the test;g) the date of the test. ISO 2015 All rights reserved 3BS EN ISO 6271:2015ISO 6271:2015(E)Annex A (normative) Platinum-cobalt colour standardsA.1 ReagentsIn preparing these standards, use only reagents of recognized analytical grade and only water of at l
46、east grade 3 purity as defined in ISO 3696.A.1.1 Potassium hexachloroplatinate(IV), K2PtCl6.A.1.2 Cobalt(II) chloride hexahydrate, CoCl2 6H2O.A.1.3 Hydrochloric acid, 38 % (by mass), = 1,19 g/ml.A.2 Preparation of colour standardsA.2.1 Pt-Co stock solution, 500 Pt-Co unitsIntroduce 1,245 g of potass
47、ium hexachloroplatinate(IV) and 1,000 g of cobalt(II) chloride hexahydrate into a 400 ml beaker. Add 100 ml of water and 100 ml of hydrochloric acid and warm, if necessary, to obtain a clear solution. After cooling, transfer quantitatively to a 1 000 ml one-mark volumetric flask, dilute to the mark
48、with water and mix well.The stock solution prepared in this way shall have tristimulus values X, Y, Z which lie within the limits specified in Table A.1 when measured in accordance with 4.1 and 4.2 using cells of 50 mm optical path length in the spectrophotometer.Table A.1 Tristimulus tolerance limi
49、ts for 500 Pt-Co units stock solutionX Y Z79,5 0,3 81,4 0,5 29,7 1,2A.2.2 Pt-Co standard matching solutionPrepare a series of standard matching solutions covering the range required (see Table A.2). Place the indicated volumes of stock solution (A.2.1) into a series of 100 ml flask, dilute to the mark with water and mix well. Cap the flask, seal the caps with shellac or waterproof cement and mark the flask with the corresponding Pt-Co number.Table A.2 Pt-Co standard matching solutionsColourPt-Co unitsVolume of stock solution (A.2.1)
