1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 7783:2011Paints and varnishes Determination of water-vapourtransmission properties Cupmethod (ISO 7783:2011)BS EN ISO 7783:2011 BRITISH STANDARDNational forewordThis Br
2、itish Standard is the UK implementation of EN ISO 7783:2011.It supersedes BS EN ISO 7783-1:2000 and BS EN ISO 7783-2:1999which are withdrawnThe UK participation in its preparation was entrusted to TechnicalCommittee STI/10, Test methods for paints.A list of organizations represented on this committe
3、e can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 64430 6ICS 87.040Compliance with a British Standard cannot confer immunity fromlegal obligatio
4、ns.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 November 2011.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 7783 November 2011 ICS 87.040 Supersedes EN ISO 7783-1:1999, EN I
5、SO 7783-2:1999English Version Paints and varnishes - Determination of water-vapour transmission properties - Cup method (ISO 7783:2011) Peintures et vernis - Dtermination des proprits de transmission de la vapeur deau - Mthode de la coupelle (ISO 7783:2011) Beschichtungsstoffe - Bestimmung der Wasse
6、rdampfdurchlssigkeit - Schalenverfahren (ISO 7783:2011) This European Standard was approved by CEN on 21 November 2011. 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
7、 any alteration. Up-to-date lists and bibliographical references 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 lan
8、guage made by translation under the responsibility of a CEN member 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, Denma
9、rk, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISAT
10、ION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 7783:2011: EBS EN ISO 7783:2011EN ISO 7783:2011 (E) 3 Foreword This document (EN ISO 7
11、783:2011) 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 a
12、n identical text or by endorsement, at the latest by May 2012, and conflicting national standards shall be withdrawn at the latest by May 2012. 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 held r
13、esponsible for identifying any or all such patent rights. This document supersedes EN ISO 7783-1:1999, EN ISO 7783-2:1999. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgiu
14、m, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement
15、 notice The text of ISO 7783:2011 has been approved by CEN as a EN ISO 7783:2011 without any modification. BS EN ISO 7783:2011ISO 7783:2011(E) ISO 2011 All rights reserved iiiContents PageForeword ivIntroduction . v1 Scope 12 Normative references .13 Terms and definitions .14 Principle .35 Apparatus
16、 and materials .35.1 Substrate for non-self-supporting coatings .35.2 Test cup 35.3 Ammonium dihydrogen phosphate (NH4H2PO4) solution for wet-cup method .35.4 Desiccant for dry-cup method .35.5 Sealing material .45.6 Test enclosure 45.7 Balance .46 Preparation for the test 46.1 Sampling of coating m
17、aterial .46.2 Preparation of test pieces .46.3 Determination of the thickness of the coating 56.4 Preparation of the test assemblies .67 Procedure 68 Expression of results .78.1 Water-vapour transmission rate, null, of self-supporting coatings .78.2 Water-vapour transmission rate, null, of non-self-
18、supporting coatings .78.3 Water-vapour diffusion-equivalent air layer thickness, nulld98.4 Water-vapour resistance factor, null .99 Precision 109.1 Repeatability, (null) .109.2 Reproducibility, (null) 1010 Test report .10Annex A (informative) Derivation of Equation (8) in Subclause 8.3 for the calcu
19、lation of the water-vapour diffusion-equivalent air layer thickness, nulld.12Annex B (normative) Use of molten wax for sealing the test assembly 14Bibliography .18BS EN ISO 7783:2011ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodie
20、s (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 been established has the right to be represented on that committee. International organizations,
21、 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.International Standards are drafted in accordance with the rules given in the ISO/
22、IEC Directives, Part 2.The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the mem
23、ber bodies casting a vote.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.ISO 7783 was prepared by Technical Committee ISO/TC 35, Paints and varnishes
24、, Subcommittee SC 9, General test methods for paints and varnishes.This first edition of ISO 7783 cancels and replaces ISO 7783-1:1996 and ISO 7783-2:1999, which have been merged and technically revised. It also incorporates the Technical Corrigendum ISO 7783-1:1996/Cor.1:1998.ISO 7783:2011(E)iv ISO
25、 2011 All rights reservedBS EN ISO 7783:2011IntroductionISO 7783 is one of a series of standards dealing with the sampling and testing of paints, varnishes and related products. It describes a method for determining the water-vapour transmission rate of self-supporting and non-self-supporting coatin
26、gs.The water-vapour transmission rate is not necessarily a linear function of film thickness, temperature or relative-humidity difference. A determination carried out under one set of conditions will not necessarily be comparable with one carried out under other conditions. Therefore, it is essentia
27、l that the conditions of test are chosen to be as close as possible to the conditions of use.Water-vapour transmission is of greatest interest under conditions of high humidity. For this reason, the wet-cup method has been adopted as the reference method. By agreement, other procedures and condition
28、s, like the dry-cup method, may be used.ISO 7783:2011(E) ISO 2011 All rights reserved vBS EN ISO 7783:2011BS EN ISO 7783:2011INTERNATIONAL STANDARD ISO 7783:2011(E)Paints and varnishes Determination of water-vapour transmission properties Cup method1 ScopeThis International Standard specifies a meth
29、od for determining the water-vapour transmission properties of coatings of paints, varnishes and related products.It supplements ISO 12572. As far as possible, the procedure, the definitions and the calculations have been taken over from ISO 12572. It is recommended that ISO 12572 be consulted, if n
30、ecessary, to obtain a better understanding of the procedure specified in this International Standard.Water-vapour transmission rates of more than 680 g/(m2nulld) (i.e. water-vapour diffusion-equivalent air layer thicknesses, nulld, of less than 0,03 m) will not be accurately quantified by the test m
31、ethod described in this International Standard.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 latest edition of the referenced document (including any a
32、mendments) applies.ISO 1513, Paints and varnishes Examination and preparation of test samples ISO 2808, Paints and varnishes Determination of film thicknessISO 3233, Paints and varnishes Determination of percentage volume of non-volatile matter by measuring the density of a dried coatingISO 3696, Wa
33、ter for analytical laboratory use Specification and test methodsISO 15528, Paints, varnishes and raw materials for paints and varnishes Sampling3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1water-vapour transmission ratenullmass of water vapou
34、r that is transmitted over a given period through a given surface area of a test piece under specified constant conditions of relative humidity at each face of the test pieceNOTE 1 It is measured in grams per square metre per day g/(m2nulld).NOTE 2 A water-vapour transmission rate measured at atmosp
35、heric pressure, null, can be converted to the equivalent value at standard atmospheric pressure, null0, by multiplying by null/null0. This allows a linear correlation with the water-vapour diffusion-equivalent air layer thickness (nulld) value (see 3.3) by the factor 20,4.NOTE 3 The term “water-vapo
36、ur transmission” is often incorrectly used for water-vapour transmission rate. ISO 2011 All rights reserved 1BS EN ISO 7783:20113.2rate of flow of water vapour through the test piecenullmass of water vapour that is transmitted over a given period through a test piece under specified constant conditi
37、ons of relative humidity at each face of the test pieceNOTE It is measured in grams per hour.3.3water-vapour diffusion-equivalent air layer thicknessnulldthickness of a static air layer that has, under the same conditions of measurement, the same water-vapour transmission rate as the coating testedN
38、OTE It is measured in metres.3.4water-vapour resistance factornullfactor that indicates how many times greater the water-vapour resistance of a material is compared with a layer of static air of the same thickness at the same temperature and pressureNOTE 1 It is dimensionless.NOTE 2 The calculation
39、and use of a water-vapour resistance factor is meaningful only if the water-vapour transmission rate of a particular material is a constant, i.e. independent of the thickness, which, however, is normally not the case for coatings.3.5test piecenullnon-self-supporting coatingsnull supporting substrate
40、 with the coating applied to it or nullself-supporting coatingsnull the coating alone3.6wet-cup methodmethod of measuring water-vapour permeability in which the test piece is sealed to the rim of a cup containing a saturated aqueous solution of ammonium dihydrogen phosphateNOTE This is the most conv
41、enient manner of carrying out determinations of water-vapour permeability under conditions of high relative humidity (between 93 % and 50 %).3.7dry-cup methodmethod of measuring water-vapour permeability in which the test piece is sealed to the rim of a cup containing a desiccantNOTE This is the mos
42、t convenient manner of carrying out determinations of water-vapour permeability under conditions of low relative humidity (between 50 % and 3 %).3.8test assemblyassembly consisting of a test piece sealed to the rim of a test cup containing saturated ammonium dihydrogen phosphate solution in contact
43、with undissolved ammonium dihydrogen phosphate crystals (wet-cup method) or containing desiccant (dry-cup method)3.9test areaarea of the face of the test piece through which the water vapour flows during the testNOTE It is measured in square metres.ISO 7783:2011(E)2 ISO 2011 All rights reservedBS EN
44、 ISO 7783:20114 PrincipleA test assembly consisting of a self-supporting coating, or a non-self-supporting coating on porous substrate, sealed to the rim of a cup is placed in a test enclosure kept at a specified temperature (e.g. 23 C) and relative humidity (e.g. 50 %). The relative humidity in the
45、 cup is maintained at a constant level either at 93 % by means of a saturated salt solution (wet-cup method) or at 3 % by means of a desiccant (dry-cup method). Because of the difference between the partial pressure of the water vapour inside the test cup and the partial pressure of the water vapour
46、 in the test enclosure, water vapour diffuses through the coating under test. By weighing the test assembly at suitable time intervals, the change in mass of the test assembly is followed. From the change in mass and the test area, the water-vapour transmission rate and the water-vapour diffusion-eq
47、uivalent air layer thickness are calculated.5 Apparatus and materials5.1 Substrate for non-self-supporting coatingsAny homogenous, porous material which has a water-vapour transmission rate above 240 g/(m2nulld) is suitable for use as the substrate for non-self-supporting coatings, for instance poly
48、ethylene frits, cellular-concrete discs, glass frits, unglazed ceramic tiles.When using cellular-concrete substrates, the coating shall be applied on the smooth side.If the coating system under test does not include a primer and it is necessary to use one before applying the coating system under tes
49、t, do so, but the transmission rate of the primed substrate will have to be determined separately.5.2 Test cupTest cups are made of glass, plastic or metal. The test cup used shall be resistant to corrosion under the conditions of the test.NOTE For aluminium test cups, a wall thickness of 1 mm has been found to be satisfactory.The exact surface area of the test piece exposed is defined by the design of the cup. The area of the exposed surface shall be at least 50 cm2for non-self-supporting coatings and at least 10 cm2for self-supporting
