1、BRITISH STANDARD BS EN ISO 8781-2:1995 Incorporating Amendment No.1 Pigments and extenders Methodsofassessment of dispersion characteristics Part2: Assessment from the change in fineness of grind The European Standard EN ISO8781-2:1995 has the status of a British StandardBSENISO8781-2:1995 This Brit
2、ish Standard, having been prepared under the directionof the Pigments, Paintsand Varnishes StandardsPolicy Committee, waspublished under the authorityof the Standards Boardand comes into effect on 30 April1991 BSI 04-2000 The following BSI references relate to the work on this standard: Committee re
3、ference PVC/1 Draft for comment 86/52359 DC ISBN 0 580 19541 4 Committees responsible for this BritishStandard The preparation of this BritishStandard was entrusted by the Pigments, Paints and Varnishes Standards Policy Committee(PVC/-) to Technical Committee PVC/1, upon which the following bodies w
4、ere represented: Aluminium Powder and Paste Association British Cement Association British Railways Board Chemical Industries Association Oil and Colour Chemists Association Paintmakers Association of Great Britain Ltd. Titanium Pigment Manufacturers Technical Committee Zinc Development Association
5、Amendments issued since publication Amd. No. Date Comments 8530 August 1995 Indicated by a sideline in the marginBSENISO8781-2:1995 BSI 04-2000 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 Text of EN ISO8781-2 3 Publication(s) referred to Inside back cove
6、rBSENISO8781-2:1995 ii BSI 04-2000 National foreword This Part of BS3483 has been prepared under the direction of the Pigments, Paints and Varnishes Standards Policy Committee. It is identical with ISO8781-2:1990 “Pigments and extenders Methods of assessment of dispersion characteristics Part2: Asse
7、ssment from the change in fineness of grind”, published by the International Organization for Standardization (ISO). In1994 the European Committee for Standardization(CEN) accepted ISO8781-2:1990 as European Standard EN ISO8781-2:1995. As a consequence of implementing the European Standard this Brit
8、ishStandard is renumbered as BS EN ISO8781-2 and any reference to BS3483-E2 should be read as a reference to BS EN ISO8781-2. An introduction is included in ISO8781-2:1990 which reads as follows. The change of fineness of grind of a pigment in a dispersion is dependent on the amount of work done in
9、the preparation of the dispersion of the pigment in a binder system. The ease with which ultimate fineness of grind is achieved may therefore be used to assess the dispersion characterisitics of that pigment. Thus, if the ultimate fineness of grind can be attained easily, the pigment is considered t
10、o be readily dispersible. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-reference
11、s International Standard Corresponding BritishStandard ISO1524:1983 BS3900 Methods of test for paints Part C6:1983 Determination of fineness of grind (Identical) BS3483 Methods for testing pigments for paints ISO8780-1:1990 Part D1:1991 Methods of dispersion for assessment of dispersion characterist
12、ics (Introduction) (Identical) ISO8780-2:1990 Part D2:1991 Method of dispersion for assessment of dispersion characteristics using an oscillatory shaking machine (Identical) ISO8780-3:1990 Part D3:1991 Method of dispersion for assessment of dispersion characteristics using a high-speed impeller mill
13、 (Identical) ISO8780-4:1990 Part D4:1991 Method of dispersion for assessment characteristics using a bead mill (Identical) ISO8780-5:1990 Part D5:1991 Method of dispersion for assessment of dispersion characteristics using an automatic muller (Identical) ISO8780-6:1990 Part D6:1991 Method of dispers
14、ion for assessment of dispersion characteristics using a triple-roll mill (Identical) Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN ISOtitle page, pages2 to6, an inside back cover and a back cover. This standard has been updated (see copyright d
15、ate) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO8781-2 March1995 ICS 87.060.10 Descriptors: Paints, pigments, extenders, tests, determination, dispersibility English version
16、 Pigments and extenders Methods of assessment of dispersion characteristics Part2: Assessment from the change in fineness of grind (ISO8781-2:1990) Pigments et matires de charge Mthodes dvaluation de la dispersibilit Partie2: Evaluation partir de la variation de la finesse de broyage (ISO8781-2:1990
17、) Pigmente und Fllstoffe Verfahren zur Beurteilung des Dispergierverhaltens Teil2: Bestimmung der nderung der Mahlfeinheit (Krnigkeit) (ISO8781-2:1990) This European Standard was approved by CEN on1994-10-17. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate t
18、he conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists i
19、n three official versions(English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies o
20、f Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretari
21、at: rue de Stassart 36, B-1050 Brussels 1995 All rights of reproduction and communication in any form and by any means reserved in all countries to CEN and its members Ref. No. EN ISO8781-2:1995 EENISO8781-2:1995 BSI 04-2000 2 Foreword This European Standard has been taken over by the Technical Comm
22、ittee CEN/TC298, Pigments and extenders, from the work of ISO/TC35, Paints and varnishes, of the International Organization for Standardization(ISO). 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 b
23、y September1995, and conflicting national standards shall be withdrawn at the latest by September1995. According to the CEN/CENELEC Internal Regulations, the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Irela
24、nd, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. NOTENormative references to international publications are given in Annex ZA (normative). Contents Page Foreword 2 1 Scope 3 2 Normative references 3 3 Principle 3 4 Required supplementary informatio
25、n 3 5 Apparatus 3 6 Procedure 3 6.1 Dispersion 3 6.2 Determination of fineness of grind 4 7 Expression of results 4 8 Test report 4 Annex A (normative) Required supplementary information 5 Annex ZA (normative) Normative references to international publications with their relevant European publicatio
26、ns 6ENISO8781-2:1995 BSI 04-2000 3 1 Scope This part of ISO8781 specifies a method for assessing, on the basis of fineness of grind, the dispersion characteristics of pigments which have been dispersed by one of the methods of dispersion described in ISO8780. It should be read in conjunction with IS
27、O8780-1. The method is of general use for comparing similar pigments, for example a test pigment against an agreed reference pigment. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this part of ISO8781. At the time of
28、 publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this part of ISO8781 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registe
29、rs of currently valid International Standards. ISO1524:1983, Paints and varnishes Determination of fineness of grind. ISO8780-1:1990, Pigments and extenders Methods of dispersion for assessment of dispersion characteristics Part1: Introduction. ISO8780-2:1990, Pigments and extenders Methods of dispe
30、rsion for assessment of dispersion characteristics Part2: Dispersion using an oscillatory shaking machine. ISO8780-3:1990, Pigments and extenders Methods of dispersion for assessment of dispersion characteristics Part3: Dispersion using a high-speed impeller mill. ISO8780-4:1990, Pigments and extend
31、ers Methods of dispersion for assessment of dispersion characteristics Part4: Dispersion using a bead mill. ISO8780-5:1990, Pigments and extenders Methods of dispersion for assessment of dispersion characteristics Part5: Dispersion using an automatic muller. ISO8780-6:1990, Pigments and extenders Me
32、thods of dispersion for assessment of dispersion characteristics Part6: Dispersion using a triple-roll mill. 3 Principle The pigment under test and, if provided, the agreed reference pigment are each dispersed in stages under specified conditions in an agreed binder system. After each incremental di
33、spersion stage, a portion of the mill base is taken and its fineness of grind is determined as described in ISO1524. The fineness-of-grind values are plotted graphically as a function of the dispersion work done (expressed as time, number of revolutions, etc.). From the graph, the work necessary to
34、obtain an agreed fineness of grind is determined. 4 Required supplementary information For any particular application, the test method specified in this part of ISO8781 needs to be completed by supplementary information. The items of supplementary information are given in Annex A. 5 Apparatus Ordina
35、ry laboratory apparatus and glassware, together with the following: 5.1 Fineness-of-grind gauge, complying with the requirements of ISO1524 maximum depth of groove(s)504m or1004m, depending on the pigment or extender and the resulting fineness of grind, but preferably504m. 5.2 Spatula 6 Procedure 6.
36、1 Dispersion Disperse each pigment sample in the agreed binder system at the agreed concentration using one of the methods described in ISO8780. Carry out the dispersion of the mill base in at least four stages and select the intermediate stages such that they are approximately in geometric progress
37、ion. The final stage should be selected so that the fineness of grind of the pigment sample is better than or equal to that agreed. The intermediate stages should correspond to successive halving of the period required to attain the final stage.ENISO8781-2:1995 4 BSI 04-2000 If the ease of dispersio
38、n of the pigment to be tested under the given conditions is not known and thus the maximum dispersion effort to be used cannot be defined, then it should be determined in initial exploratory tests. For this, it is recommended that the fineness of grind of the pigment for at least two dispersion stag
39、es is determined. These fineness-of-grind values are plotted using logarithmic scales for both axes and the line joining these plotted values is extrapolated to a suitable target level of dispersion. Suitable intermediate dispersion levels are then selected. NOTE 1A fineness of grind of54m may be fo
40、und to be a suitable target dispersion level, although for less easily dispersed pigments104m to204m may be acceptable. 6.2 Determination of fineness of grind Using the spatula(5.2), take small samples from the mill base after each of the specified dispersion stages, and determine the fineness of gr
41、ind in each case using the method described in ISO1524. If the fineness of grind agreed as a target level is not attained after the last of the specified dispersion stages, proceed as instructed in7.2. 7 Expression of results 7.1 Plot the fineness-of-grind readings, in micrometres, obtained in6.2 as
42、 a function of the incremental dispersion stages (which may be expressed as time, number of revolutions, etc.), using a logarithmic scale for both axes. Connect the points with a smooth curve. NOTE 2Generally, nearly linear curves are obtained in this way, thus aiding interpolation. Determine the wo
43、rk necessary to attain the target fineness of grind, by interpolation, from the graph, expressing the result as milling time, number of revolutions of an automatic muller, etc. 7.2 In cases where the agreed fineness of grind cannot be attained, report the fineness measured after the final dispersion
44、 stage as the highest practically attainable fineness of grind. 8 Test report The test report shall contain at least the following information: a) all details necessary to identify the product tested; b) a reference to this part of ISO8781 and the relevant part of ISO8780; c) the items of supplement
45、ary information referred to in Annex A; d) the dispersion work done(see7.1) and the corresponding target level of fineness of grind or, if the agreed target level was not achieved, the highest practically attainable fineness of grind together with the work required to reach it (see7.2); e) the graph
46、 representing the development of fineness of grind(see7.1); f) any deviation from the procedure specified; g) the date(s) of the test.ENISO8781-2:1995 BSI 04-2000 5 Annex A (normative) Required supplementary information The items of supplementary information listed in this annex shall be supplied as
47、 appropriate to enable the method to be carried out. The information required should preferably be agreed between the interested parties and may be derived, in part or totally, from an international or national standard or other document related to the product under lest. a) Method of dispersion(see
48、ISO8780). b) Type and designation of the binder. c) A particular fineness of grind as a target level. d) Reference pigment(if any).ENISO8781-2:1995 6 BSI 04-2000 Annex ZA (normative) Normative references to international publications with their relevant European publications This European Standard i
49、ncorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies(including amendments). Publication Year Title EN Year ISO1524 1983 Paints varnishes
