1、BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06General methods of test for pigments and extendersPart 21: Comparison of heat stability of pigments using a stoving medium (ISO 787-21:1979)BS EN ISO 787-21:2017EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 7
2、87-21 October 2017 ICS 87.060.10 English Version General methods of test for pigments and extenders - Part 21: Comparison of heat stability of pigments using a stoving medium (ISO 787-21:1979) Mthodes gnrales dessai des pigments et matires de charge - Partie 21: Comparaison de la stabilit la chaleur
3、 des pigments en utilisant un liant au four (ISO 787-21:1979) Allgemeine Prfmethoden fr Pigmente und Fllstoffe -Teil 21: Vergleich der Hitzebestndigkeit von Pigmenten unter Verwendung eines Einbrennbindemittels (ISO 787-21:1979) This European Standard was approved by CEN on 21 September 2017. CEN me
4、mbers 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 concerning such national standards may be obtained on applica
5、tion 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 member into its own language and notified to the CEN-CENELEC Manag
6、ement 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia
7、, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenu
8、e Marnix 17, B-1000 Brussels 2017 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 787-21:2017 ENational forewordThis British Standard is the UK implementation of EN ISO 78721:2017. It is identical to ISO 78721:1979. It supersed
9、es BS 3483C8:1980, which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee STI/1, Pigments.A list of organizations represented on this committee can be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 provisio
10、ns of a contract. Users are responsible for its correct application. The British Standards Institution 2018 Published by BSI Standards Limited 2018ISBN 978 0 580 96832 7ICS 87.060.10Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published u
11、nder the authority of the Standards Policy and Strategy Committee on 31 January 2018.Amendments/corrigenda issued since publicationDate Text affected31 January 2018 This corrigendum renumbers BS 3483C8:1980 as BS EN ISO 78721:2017BRITISH STANDARDBS EN ISO 78721:2017EUROPEAN STANDARD NORME EUROPENNE
12、EUROPISCHE NORM EN ISO 787-21 October 2017 ICS 87.060.10 English Version General methods of test for pigments and extenders - Part 21: Comparison of heat stability of pigments using a stoving medium (ISO 787-21:1979) Mthodes gnrales dessai des pigments et matires de charge - Partie 21: Comparaison d
13、e la stabilit la chaleur des pigments en utilisant un liant au four (ISO 787-21:1979) Allgemeine Prfmethoden fr Pigmente und Fllstoffe -Teil 21: Vergleich der Hitzebestndigkeit von Pigmenten unter Verwendung eines Einbrennbindemittels (ISO 787-21:1979) This European Standard was approved by CEN on 2
14、1 September 2017. 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 concerning such national standards ma
15、y 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 member into its own language and notified
16、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, France, Germany, Greece, Hungary, Iceland
17、, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC
18、Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 787-21:2017 EBS EN ISO 78721:2017EN ISO 787-21:2017 (E) 3 European foreword The text of ISO 787-21:1979 has been prepared
19、 by Technical Committee ISO/TC 256 “Pigments, dyestuffs and extenders” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 787-21:2017 by Technical Committee CEN/TC 298 “Pigments and extenders” the secretariat of which is held by DIN. This European Standard
20、shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by April 2018, and conflicting national standards shall be withdrawn at the latest by April 2018. Attention is drawn to the possibility that some of the elements of this docu
21、ment may be the subject of patent rights. CEN shall not be held responsible for identifying any or all such patent rights. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgiu
22、m, 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, Serbia, Slovakia, Slovenia, Spain, Sweden,
23、Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 787-21:1979 has been approved by CEN as EN ISO 787-21:2017 without any modification. BS EN ISO 78721:2017Foreword IS0 (the international Organization for Standardization) is a worldwide federation of national standards in
24、stitutes (IS0 member bodies). The work of developing Interna- tional Standards is carried out through IS0 technical committees. Every member body interested in a subject for which a technical committee has been set up has the right to be represented on that committee. International organizations, go
25、vernmental and non- governmental, in liaison with ISO, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the IS0 Council. International Standard IS0 787/
26、21 was developed by Technical Committee ISO/TC 35, Paints and varnishes, and was circulated to the member bodies in March 1978. It has been approved by the member bodies of the following countries : The member body tech nical gro #unds Australia Israel Bulgaria Italy Canada Kenya Egypt, Arab Rep. of
27、 Korea, Rep. of Germany, F. R. Netherlands India New Zealand Iran Norway Ireland Poland of the following country expressed disapproval of the document on Romania South Africa, Rep. of Sweden Switzerland Turkey United Kingdom Yugoslavia France International Organization for Standardization, 1979 Prin
28、ted in Switzerland ii BS EN ISO 78721:2017The purpose of this International Standard is to establish a series of general test methods for pigments and extenders which are suitable for all or many of the individual pigments and extenders for which specifications might be required. In such cases, a cr
29、oss-reference to the general method should be included in the International Standard relating to that pigment or extender, with a note of any detailed modifications which might be needed in view of the special properties of the product in question. Technical Committee lSO/TC 35 decided that all the
30、general methods should be published as they become available, as parts of a single International Standard, in order to emphasize the relationship of each to the whole series. The Technical Committee also decided that, where two or more procedures were widely used for determining the same or a simila
31、r characteristic of a pigment or ex- tender, there would be no objection to including more than one of them in the IS0 series. In such cases it will, however, be essential to state clearly in a specification which method is to be used and, in the test report, which method has been used. Parts of the
32、 series already published are as follows : Part 1 : Comparison of colour Part 2 : Determination of matter volatile at 105 OC Part 3 : Determination of matter soluble in water - Hot extraction method Part 4 : Determination of acidity or alkalinity of the aqueous extract Part 5 : Determination of oil
33、absorption value Part 6 : Determination of residue on sieve - Oil method Part 7 : Determination of residue on sieve - Water method Part 8 : Determination of matter soluble in water - Cold extraction method Part 9 : Determination of pH value of an aqueous suspension Part 10 : Determination of density
34、 - Pyknometer method Part 11 : Determination of tamped volume and apparent density after tamping Part 12 : Visual comparison of hue of powdered white pigment (Hollow cone method)l) Part 13 : Determination of water-soluble sulphates, chlorides and nitrates Part 14 : Determination of resistivity of aq
35、ueous extract Part 15 : Comparison of resistance of coloured pigments of similar types to light from a specified light source Part 16 : Comparison of relative tinting strength (or equivalent colouring value) and colour on reduction in linseed stand oil using the automatic muller Part 17 : Comparison
36、 of lightening power of white pigments Part 18 : Determination of residue on sieve by a mechanical flushing procedure Part 19 : Determination of water-soluble nitrates - Salicylic acid method Part 20 : Comparison of ease of dispersion - Oscillatory shaking method Part 21 : Comparison of heat stabili
37、ty of pigments using a stoving medium Part 22 : Comparison of resistance to bleeding of pigments Part 23 : Determination of density (using a centrifuge to remove entrained air) 1) This part will be withdrawn as the specified method is no longer in use. BS EN ISO 78721:2017INTERNATIONALSTANDARD IS0 7
38、87/21-1979 (E) General methods of test for pigments and extenders - Part 21 : Comparison of heat stability of pigments using a stoving medium 0 Introduction This document is a part of IS0 787, Genera/methods of test for pigments and extenders. Although the method as written is intended for comparing
39、 the heat stability of pigments by specifying the temperatures of heating and the time of heating, it may also be used for deter- mining the heat resistance of a pigment. 1 Scope and field of application This part of IS0 787 specifies a general method of test for com- paring the heat stability of th
40、e pigment under test against that of an agreed sample. NOTE - When this general method is applicable to a given pigment, only a cross-reference to it should be included in the International Standard relating to that pigment, with a note of any detailed modifica- tion which may be needed in view of t
41、he special properties of the pig- ment in question. Only when this general method is not applicable to a particular pigment should a special method for comparison of heat stability be specified. 2 References IS0 842, Raw materials for paints and varnishes - Sampling. IS0 3668, Paints and varnishes -
42、 Visual comparison of the co/our of paints. 3 Apparatus and materials 3.1 Panels Any suitable light-gauge metal panels, for example of bright tinplate or aluminium, conveniently 150 mm x 100 mm, the surfaces ofwhich have been cleaned and lightly abraded, or other suitable panels as agreed between th
43、e interested parties. 3.2 Agreed stoving medium. 3.3 Oven, well ventilated and capable of being maintained at the agreed temperature. 4 Sampling Take a representative sample of the pigment to be tested as described in IS0 842. / 5 Procedure Prepare a dispersion of the pigment under test (alone or re
44、- duced to an agreed colour) in the agreed stoving medium by a suitable method to be agreed between the interested parties, including dilution of the dispersion to an appropriate consist- ency by further addition of the agreed medium or solvent. Prepare a dispersion of the agreed sample in the same
45、manner in the same medium. Apply the dispersion of the pigment under test by an agreed method over the whole surface of a test panel, to give a wet film thickness of 75 to 120 pm. Apply the dispersion of the agreed sample in the same manner to the whole surface of another panel. Allow the coated pan
46、els to remain at 23 + 2 OC and (50 k 5W r I t o e a rve humidity for 30 min and then cut each panel into a suitable number of strips, each not less than 30 mm wide, to carry out the required tests, labelling each strip. Stove one strip of each panel for an adequate period at the lowest temperature t
47、hat will ensure full curing of the film. NOTE - These panels are the standards against which other panels will be compared. Stove other strip(s) of the panels coated with the test sample and agreed sample respectively at the temperature(s) and for the time(s) agreed between the interested parties. A
48、llow the panels to cool to room temperature. By the procedure described in IS0 3668, compare in diffuse daylight the panels stoved at the higher temperature(s) of both the test sample and the agreed sample with the corresponding standard panels stoved at the minimum temperature. If daylight is not a
49、vailable, make the comparison in artificial daylight. If required, the comparison shall be repeated after 48 h. 1 BS EN ISO 78721:2017IS0 787121-1979 Note the degree of co El Dur change of the pigment under test as being less than, equal to, or greater than the colour change of the agreed sample, stating for how long and at what temperature the particular panels were stoved. NOTE - If required and agreed, a suitable calorimeter may be used for measuring the colour differences, in which case ensure that the panel is sufficiently large to p
