DIN EN ISO 4628-6-2011 Paints and varnishes - Evaluation of degradation of coatings - Designation of quantity and size of defects and of intensity of uniform changes in appearance .pdf

1、December 2011 Translation by DIN-Sprachendienst.English price group 8No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).IC

2、S 87.040!$xNS“1854348www.din.deDDIN EN ISO 4628-6Paints and varnishes Evaluation of degradation of coatings Designation of quantity and size of defects, and of intensity of uniformchanges in appearance Part 6: Assessment of degree of chalking bytape method (ISO 4628-6:2011)English translation of DIN

3、 EN ISO 4628-6:2011-12Beschichtungsstoffe Beurteilung von Beschichtungsschden Bewertung der Menge und der Gre von Schden und der Intensitt von gleichmigenVernderungen im Aussehen Teil 6: Bewertung des Kreidungsgrades nach demKlebebandverfahren (ISO 4628-6:2011)Englische bersetzung von DIN EN ISO 462

4、8-6:2011-12Peintures et vernis valuation de la dgradation des revtements Dsignation de la quantit et de la dimension des dfauts, et de lintensit deschangements uniformes daspect Partie 6: valuation du degr de farinage par lamthode du ruban adhsif (ISO 4628-6:2011)Traduction anglaise de DIN EN ISO 46

5、28-6:2011-12SupersedesDIN EN ISO 4628-6:2007-11www.beuth.deIn case of doubt, the German-language original shall be considered authoritative.Document comprises 0 pages11.111DIN EN ISO 4628-6:2011-12 A comma is used as the decimal marker. National foreword This standard has been prepared by Technical

6、Committee ISO/TC 35 “Paints and varnishes”, Subcommittee SC 9 “General test methods for paints and varnishes” (Secretariat: BSI, United Kingdom) in collaboration with Technical Committee CEN/TC 139 “Paints and varnishes” (Secretariat: DIN, Germany). The responsible German body involved in its prepar

7、ation was the Normenausschuss Beschichtungsstoffe und Beschichtungen (Coatings and Coating Materials Standards Committee), Working Committee NA 002-00-07 AA Allgemeine Prfverfahren fr Beschichtungsstoffe und Beschichtungen. The tape method using a colourless, transparent tape is suitable for both wh

8、ite and coloured coatings. It must be noted that “chalking” is not to be confused with “efflorescence”, in which dissolved pigment crystallizes on the surface of the coating without the binder being destroyed. Efflorescence is not dealt with in this standard. Where dirt adheres to the surface of coa

9、tings exposed to natural weathering, the appearance of the tape may seem to indicate chalking when in fact it is only the layer of dirt that has been lifted off the coating surface. By careful examination of the tape it is relatively easy to distinguish between dirt and chalking pigment. When storin

10、g white-chalked tape on a background with a free adhesive surface a piece of tape of the same type and quality can be placed next to it. However the tape can also be placed on a glossy surface (such as cling film) and put back on the background (see Subclause 4.2) at any time. Pieces of tape with co

11、loured pigment are best stored on white card. The DIN Standard corresponding to the International Standard referred to in the EN is as follows: ISO 4628-1 DIN EN ISO 4628-1 Amendments This standard differs from DIN EN ISO 4628-6:2007-11 as follows: a) the pictorial standards (photographic pictures)

12、used in the first edition (ISO 4628:6:1990, identical with DIN EN ISO 4628-6:2002-02) have been re-inserted because the computer-generated chalking scale used in the second edition (ISO 4628-6:2007, identical with DIN EN ISO 4628-6:2007-11) did not always give the same rating as that given by the sc

13、ale used in the first edition (for more details, see Introduction); b) a limiting value of the transmittance of the tape below which chalking is considered to have taken place has been added (see 5.2). Previous editions DIN 53223: 1973-12 DIN EN ISO 4628-6: 2002-02, 2007-11 National Annex NA (inform

14、ative) Bibliography DIN EN ISO 4628-1, Paints and varnishes Evaluation of degradation of coatings Designation of quantity and size of defects, and of intensity of uniform changes in appearance Part 1: General introduction and designation system 2 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN

15、ISO 4628-6 September 2011 ICS 87.040 Supersedes EN ISO 4628-6:2007English Version Paints and varnishes - Evaluation of degradation of coatings - Designation of quantity and size of defects, and of intensity of uniform changes in appearance - Part 6: Assessment of degree of chalking by tape method (I

16、SO 4628-6:2011) Peintures et vernis - valuation de la dgradation des revtements - Dsignation de la quantit et de la dimension des dfauts, et de lintensit des changements uniformes daspect - Partie 6: valuation du degr de farinage par la mthode du ruban adhsif (ISO 4628-6:2011) Beschichtungsstoffe -

17、Beurteilung von Beschichtungsschden - Bewertung der Menge und der Gre von Schden und der Intensitt von gleichmigen Vernderungen im Aussehen - Teil 6: Bewertung des Kreidungsgrades nach dem Klebebandverfahren This European Standard was approved by CEN on 31 August 2011. CEN members are bound to compl

18、y 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 application to the CEN-CENELEC

19、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 Management Centre has the sam

20、e status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Po

21、rtugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. 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 4628-6:2011: E(ISO 4628-6:2011) EUROP

22、EAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Foreword This document (EN ISO 4628-6:2011) has been prepared by Technical Committee ISO/TC 35 Paints and varnishes” in collaboration with Technical Committee CEN/TC 139 “Paints and varnishes” the secreta

23、riat 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 March 2012, and conflicting national standards shall be withdrawn at the latest by March 2012. Attention is drawn to t

24、he possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 4628-6:2007. According to the CEN/CENELEC Internal Regulations, the national

25、standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norw

26、ay, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 4628-6:2011 has been approved by CEN as a EN ISO 4628-6:2011 without any modification. 2DIN EN ISO 4628-6:2011-12 EN ISO 4628-6:2011 (E) Introduction ISO 4628-1 de

27、fines the system for designating the quantity and size of defects and the intensity of uniform changes of coatings and outlines the general principles of the system. This system is intended to be used, in particular, for defects caused by ageing and weathering, and for uniform changes such as colour

28、 changes, for example yellowing. The other parts of ISO 4628 provide pictorial standards or other means for evaluating particular types of defect. As far as possible, already existing evaluation schemes have been used as the basis. The chalking scale used in the first (1990) edition and in this thir

29、d edition of ISO 4628-6 consists of photographic pictures of adhesive tapes with different amounts of pigment particles adhering to them. The pigment particles are not evenly distributed over each tape. The lower ratings in particular (i.e. 1 to 3) give the impression of cloudiness. All five ratings

30、 in the scale used in the first (1990) edition and in this edition are sufficiently different for visual-assessment purposes, however. The scale used in the second (2007) edition was computer-generated. Thus the white dots representing the pigment particles were distributed very evenly over the tape

31、, with the result that not all the ratings differed sufficiently well from each other for visual assessment to be carried out. While ratings 0,5 to 3,0 on the black background on the 2007 scale could be differentiated sufficiently well from each other, it was hardly possible to differentiate visuall

32、y between ratings above 3,0, especially ratings 4 and 5. On the white background, the difference between ratings 0,5, 1,0 and 1,5 was not easy to discern. The differences between ratings 1,5 to 5,0 were more evident, however. Comparing the 1990 scale with the 2007 scale, it would appear that rating

33、1 on the 1990 scale corresponded to 0,5 on the 2007 scale, and rating 2 on the 1990 scale corresponded to 1 on the 2007 scale. It was therefore decided that the 2007 scale was unsuitable for use in the visual assessment of the degree of chalking of paints over the whole rating scale from 0,5 to 5,0.

34、 3DIN EN ISO 4628-6:2011-12 EN ISO 4628-6:2011 (E) IMPORTANT For the assessment of the degree of chalking by the tape method, it is necessary to use the pictorial reference standards contained in this part of ISO 4628. Owing to the fact that electronic copies of these standards are subject to change

35、 when viewed on screen or printed, it is recommended that only the pictorial standards contained in printed copies of this part of ISO 4628 purchased from ISO member bodies or their distributors be used when comparing test results. 1 Scope This part of ISO 4628 provides pictorial reference standards

36、 for designating the degree of chalking of paint coatings. It also describes a method by which the degree of chalking is rated. In using this method, it is essential that care be taken to distinguish between true degradation products and adhering dirt, particularly when chalking is slight. 2 Terms a

37、nd definitions For the purposes of this document, the following terms and definitions apply. 2.1 chalking appearance of a loosely adherent fine powder on the surface of a paint coating, arising from the degradation of one or more of its constituents 3 Principle The chalking is removed from the coati

38、ng under test using an adhesive tape. The chalking adhering to the tape is examined against a contrasting background (either black or white, whichever gives the greater contrast) and the degree of chalking is assessed with reference to a rating scale. 4 Materials 4.1 Self-adhesive transparent tape,

39、of width at least 15 mm. Commercially available flexible tapes, transparent and without perceptible colour, have been found to be satisfactory. However, the quality of the tape affects the rating obtained. The type of tape shall therefore be agreed on between the interested parties and shall be stat

40、ed in the test report. 4.2 Background, black or white, with matt finish, for example card or velvet having a short pile without a tendency to be crushed. 4DIN EN ISO 4628-6:2011-12 EN ISO 4628-6:2011 (E) 5 Procedure 5.1 Allow the surface to dry at room temperature before carrying out the test. Place

41、 a piece of the adhesive tape (4.1) on the dry coating by applying firm pressure and rubbing with a finger. The length of the tape should be at least 40 mm. Remove the tape perpendicularly to the surface and lay it on a background (4.2) of the appropriate colour to give the greater contrast, with th

42、e adhesive in contact with the background. Assess light-coloured coatings on the black background and dark-coloured coatings on the white background. Under consistent illumination, immediately assess (see 5.5) the degree of chalking by comparing the amount of chalk on the tape with the pictorial ref

43、erence standards in Figure 1. The more background that is visible, the lower the rating. Report the illumination in the test report. 5.2 The degree of chalking may also be determined quantitatively using a suitable photoelectric instrument to compare the transmittance of the chalked tape with that o

44、f unused tape. In this procedure, the adhesive tape shall not be placed on a background (4.2) but on a clean glass slide or open support, which is placed in the optical beam of the instrument2,3. A transmittance of less than 70 % of that of the unused tape indicates chalking. This instrumental metho

45、d shall only be used if the pattern of chalking residues on the tape is homogeneous. 5.3 The degree of chalking can vary over a given area. On large areas with a uniform surface (no texture), the determination should preferably be made at several locations and the mean and range reported. Apply the

46、tape to an area of the panel that has not been used for previous measurements to avoid false readings. 5.4 Ratings obtained with coatings exposed to natural weathering shall be treated with caution as dirt deposited on the surface from the atmosphere can give false values of chalking. 5.5 After remo

47、ving the chalking from the coating under test, the assessment of each piece of adhesive tape shall be carried out without delay because the appearance of the chalking residues on the adhesive tape and the transmittance of the tape might change with time. 5.6 When testing low-gloss paint coatings, a

48、certain amount of loosely adherent material might be observed, even with unweathered panels. A blank test, carried out on an unweathered panel, is therefore recommended for such coatings. 6 Rating Rate the degree of chalking by reference to the pictorial standards shown in Figure 1. NOTE The numeric

49、al values given correspond to those in ISO 4628-1. For textured surfaces, the rating shall be based on the observations of the most intensively chalked parts of the tape. 5DIN EN ISO 4628-6:2011-12 EN ISO 4628-6:2011 (E) 7 Test report The test report shall contain at least the following information: a) all information necessary for the identification of the sample tested; b) a reference to this part of ISO 4628 (ISO 4628-6:2011); c) details of the method used, including: 1) the type of weathering (artificial or