BS EN ISO 787-25-1994 General methods of test for pigments and extenders - Comparison of the colour in full-shade systems of white black and coloured pigments - Colorimetric method.pdf

1、BRITISH STANDARDBS EN ISO 787-25:2006 BS 3483-A7:2006Incorporating amendment no. 1 to BS 3483-A7:1994 (renumbers the BS as BS EN ISO 787-25:2006)paints ICS 87.060.10g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g

2、48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58Part A7: Colorimetric method for the comparison of the colours, in full-shade systems, of white, black and coloured pigmentsThe European Standard BS EN ISO 787-25:2006 has the status of a British StandardMethods forTesting pigments for

3、 Precast Concrete Federation Ltd.tish Railways BoardBS EN ISO 787-25:2006Committees responsible for this British StandardThTreaCoBrBriBriBritish BriCement and Concrete PThis British Standard, having been prepared under the direction of the Surface Treatments and Coatings Standards Policy Committee,

4、was published under the authority of the Standards Board and comes into effect on 15 March 1994 BSI 2007The following BSI references relate to the work on this standard:Committee reference STC/1Draft for comment 91/57132 DCISBN 0 580 22977 7igment Suppliers AssociationChina Clay AssociationOil and C

5、olour Chemists AssociationTitanium Pigment Manufacturers Technical CommitteeZinc Development AssociationAmendments issued since publicationAmd. No. Date Comments16828 31 January 2007 Renumbers BS 3483-A7:1994 as BS EN ISO 787-25:2006e preparation of this British Standard was entrusted by the Surface

6、 tments and Coatings Standards Policy Committee (STC/-) to Technical mmittee STC/1, upon which the following bodies were represented:itish Cement Associationtish Coatings Federation Ltd.tish Colour Makers AssociationBS EN ISO 787-25:2006 BSI 2007ContentsPageCommittees responsible Inside front coverN

7、ational foreword ii1Scope 12 Normative references 13 Definitions 14Principle 15 Materials 26 Apparatus 27Sampling 38 Procedure 39 Expression of results 510 Test report 5Figure 1 Black standard 3Table 1 Recommended quantities of white pigment and test medium 2Table 2 Recommended quantities of coloure

8、d and black pigments and test medium 2Table 3 Name of relative hue 5List of references Inside back coveriBS EN ISO 787-25:2006iiNational forewordThis British Standard was published by BSI. It is the UK implementation of EN ISO 787-25:2006. It is identical with ISO 787:1993.The UK participation in it

9、s preparation was entrusted to Technical Committee STI/1, Pigments.A list of organizations represented on this committee can be obtained on request to its secretaryCross-referencesInternational Standard Corresponding British StandardISO 787-9:1981 BS 3483 Methods for testing pigments for paintsPart

10、C4:1982 Determination of pH value of an aqueous suspension(Identical)ISO 842:1984 BS 4726:1986 Methods for sampling raw materials for paints and varnishes(Identical)ISO 3219:1993 BS 2782 Methods of testing plasticsPart 7 Rheological propertiesMethod 730B:1993 Determination of the viscosity of polyme

11、rs in the liquid, emulsified or dispersed state using a rotational viscometer working at a defined shear rate(Identical)BS 6782 Binders for paintsISO 3682:1983 Part 3:1987 Method for determination of acid value (titrimetric method)(Identical)ISO 4629:1978 Part 4:1987 Method for determination of hydr

12、oxyl value (titrimetric method)(Identical)BS 3900 Methods of test for paintsISO 7724-1:1984 Part D8: 1986 Determination of colour and colour difference: principles(Identical)ISO 7724-2:1984 Part D9:1986 Determination of colour and colour difference: measurement(Identical)ISO 7724-3:1984 Part D10:198

13、6 Determination of colour and colour difference: calculation(Identical)ISO 8780-6:1990 BS 3483 Methods for testing pigments for paintsPart D6:1991 Method of dispersion for assessment of dispersion characteristics using a triple-roll mill(Identical) BSI 2007 BSI 2007The Technical Committee has review

14、ed the provisions of ASTM D 16:1991, ASTM D 387:1986 and ASTM D 3022:1984, to which normative reference is made in the text, and has decided that they are acceptable for use in conjunction with this standard.This publication does not purport to include all the necessary provisions of a contract. Use

15、rs of British Standards are responsible for their correct application.Compliance with a British Standard cannot confer immunity from legal obligations.BS EN ISO 787-25:2006iiiivblankEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 787-25November 2006ICS 87.060.10English VersionGeneral methods o

16、f test for pigments and extenders - Part 25:Comparison of the colour, in full-shade systems, of white, blackand coloured pigments - Colorimetric method (ISO 787-25:1993)Mthodes gnrales dessai des pigments et matires decharge - Partie 25: Comparaison, dans les systmesmonopigmentaires, de la couleur d

17、es pigments blancs,noirs et colors - Mthode colorimtrique (ISO 787-25:1993)Allgmeine Prfverfahren fr Pigmente und Fllstoffe - Teil25: Vergleich der Farbe von Wei-, Schwarz- undBuntpigmenten in Purton-Systemen - FarbmetrischesVerfahren (ISO 787-25:1993)This European Standard was approved by CEN on 21

18、 October 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be o

19、btained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Sec

20、retariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Port

21、ugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2006 CEN All rights of exploitation in any form and by any means re

22、servedworldwide for CEN national Members.Ref. No. EN ISO 787-25:2006: EForeword The text of ISO 787-25:1993 has been prepared by Technical Committee ISO/TC 35 “Paints and varnishes” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 787-25:2006 by Technical

23、 Committee CEN/TC 298 “Pigments and extenders“, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by May 2007, and conflicting national standards shall be withd

24、rawn at the latest by May 2007. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ice

25、land, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of ISO 787-25:1993 has been approved by CEN as EN ISO 787-25:2006 without any modifications. EN I

26、SO 787-25:2006EN ISO 787-25:2006 1 ScopeThis part of ISO 787 specifies a general test method for comparing the colour, in full-shade systems, of white, black or coloured pigments with that of an agreed reference pigment, using a colorimetric procedure.NOTE 1 When the general method specified in this

27、 part of ISO 787 is applicable to a given pigment, only a cross-reference to ISO 787-25 needs to be included in the International Standard giving the specification for that pigment, indicating any detailed modification that may be needed in view of the special properties of the material in question.

28、 Only when the general method in this part of ISO 787 is not applicable to a particular material is a different photometric method for comparison of colour to be specified.ISO 787-1:1982, General methods of test for pigments and extenders Part 1: Comparison of colour of pigments, describes a general

29、 test method for visual comparison of the colour of pigments.2 Normative referencesThe following standards contain provisions which, through reference in this text, constitute provisions of this part of ISO 787. At the time of publication, the editions indicated were valid. All standards are subject

30、 to revision, and parties to agreements based on this part of ISO 787 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.ISO 787-9:1981, General meth

31、ods of test for pigments and extenders Part 9: Determination of pH value of an aqueous suspension. ISO 842:1984, Raw materials for paints and varnishes Sampling. ISO 3219:1993, Plastics Polymers/resins in the liquid state or as emulsions or dispersions Determination of viscosity using a rotational v

32、iscometer with defined shear rate. ISO 3682:1983, Binders for paints and varnishes Determination of acid value Titrimetric method. ISO 4629:1978, Paint media Determination of hydroxyl value Titrimetric method. ISO 7724-1:1984, Paints and varnishes Colorimetry Part 1: Principles. ISO 7724-2:1984, Pai

33、nts and varnishes Colorimetry Part 2: Colour measurement. ISO 7724-3:1984, Paints and varnishes Colorimetry Part 3: Calculation of colour differences. ASTM D 16-1991, Standard terminology relating to paint, varnish, lacquer and related products. ASTM D 387-1986, Standard test method for color and st

34、rength of color pigments with a mechanical muller. ASTM D 3022-1984, Standard test method for color and strength of color pigments by use of a miniature sandmill. 3 DefinitionsFor the purposes of this part of ISO 787, the following definitions apply.3.1 full-shade systema pigmented system that conta

35、ins one pigment only3.2 full-shade colourthe colour of a full-shade system that is applied in a hiding layer (optically infinite) (See also note 3.)NOTE 2 Hiding cannot be achieved with some coloured pigments of very high transparency.3.3 mass tonethe colour of a full-shade system that is not applie

36、d in a hiding layer, for example on a white test substrate (See also notes 3 and 4.)NOTE 3 The definitions given in 3.2 and 3.3 are in conflict with those in ASTM D 16 and with the usage of “mass color” in ASTM D 387 and ASTM D 3022.NOTE 4 With pigmented systems, it is possible to produce a number o

37、f different mass tones, depending on the thickness of the applied layer and the properties of the test substrate. Therefore, a mass tone is only clearly defined if the preparation, the composition, the application technique and the film thickness of the pigmented system as well as the substrate are

38、defined.4 PrincipleThe test pigment and an agreed reference pigment are dispersed in a particular test medium, consisting of a mixture of an alkyd resin and fumed silica, using an automatic muller. From the dispersions of the two pigments, specimens on suitable substrates are prepared. The tristimul

39、us values of the specimens are measured as described in ISO 7724-2 and from these the appropriate colour characteristics (relative hue and amount of chromaticity difference for black and white pigments; lightness, hue, chroma and total colour difference for coloured pigments) are calculated as descr

40、ibed in ISO 7724-3. BSI 2007 1ISO 8780-6:1990, Pigments and extenders Methods of dispersion for assessment of dispersion characteristics Part 6: Dispersion using a triple-roll mill. EN ISO 787-25:20065 Materials5.1 Alkyd resin (binder)The alkyd resin shall consist of 63 % (m/m) linseed oil, 23 % (m/

41、m) phthalic anhydride and 14 % (m/m) trimethylol propane, and shall comply with the following requirements: 5.2 Fumed silicaThe fumed silica shall comply with the following requirements: NOTE 5 Fumed silica is necessary to avoid flocculation and to control the flow properties of the pigmented system

42、.5.3 Preparation of the test mediumThe preferred test medium (see Table 1 and Table 2 for quantities) is prepared as follows:Mix well 97 parts by mass of alkyd resin (5.1) and 3 parts by mass of fumed silica (5.2). Take care that no silica is lost by evolution of dust. Disperse the mixture twice on

43、a triple-roll mill (see ISO 8780-6).Another test medium may be agreed between the interested parties. This shall be indicated in the test report. Table 1 Recommended quantities of white pigment and test medium Table 2 Recommended quantities of coloured and black pigments and test medium6 ApparatusOr

44、dinary laboratory apparatus and glassware, together with the following:6.1 Photometer6.1.1 For coloured and white pigmentsSpectrometer or tristimulus colorimeter as specified in ISO 7724-2.6.1.2 For black pigmentsSpectrometer or tristimulus colorimeter as specified in ISO 7724-2 and complying with t

45、he following requirements:a) AccuracyA spectrometer shall provide reflectance values to five decimal places; a tristimulus colorimeter shall provide tristimulus values to three decimal places.b) Calibration and zero adjustmentThe instrument should preferably be such that it can be adjusted by using

46、a suitable black standard so that the data for the tristimulus values are close to zero. If direct adjustment cannot be performed, the readings for the black standard shall be subtracted from the values for the reference and test specimens.The black standard used for the zero adjustment shall be a h

47、ighly efficient light trap as shown in Figure 1 and having the following dimensions:A W diameter of instrument sample port + 5 mmB W 80 mmC W 70 mmTest methodAcid value max. 15 mg ISO 3682KOH/gViscosity (of the product as delivered)7 Pas to 10 PasISO 3219Hydroxyl value 30 mg to 50 mg ISO 4629KOH/gTe

48、st methodSpecific surface area (BET)175 m2/g to 225 m2/gto be agreed between the interested partiespH value of a 4 % dispersion in water3,6 to 4,5 ISO 787-9Pigment (Density)g/mlMass of pigmentgVolume of test medium (5.3)mlTitanium dioxide ( = 4,0) 4,0 3,0Zinc sulfide ( = 4,0) 4,0 2,8Zinc oxide (Zinc

49、 white)( = 5,8)5,0 2,6Pigment group(see 8.1.2)Mass of pigmentgVolume of test medium (5.3)mlabc3,01,00,51,51,51,52 BSI 2007EN ISO 787-25:2006 The black standard shall have a non-gloss black interior and the bottom shall be covered with black velvet.c) Standard deviation of tristimulus valuesThe standard deviation rfor consecutive measurements of tristimulus values shall be 0,005. It shall be calculated from 20 measurements of tristimulus values without changing the position of a test specimen having a tristimul