BS EN ISO 16862-2003 Paints and varnishes - Evaluation of sag resistance《涂料和清漆 抗下垂性评估》.pdf

1、16862:2006)g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58The European Standard EN ISO 16862:2006 has the status of a British StandardICS 87.040Pai

2、nts and varnishes Evaluation of sag resistanceBRITISH STANDARDBS EN ISO 16862:2006Incorporating amendment no. 1 (renumbers BS ISO 16862:2003 as BS EN ISO BS EN ISO 16862:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 26 November 2003 BSI

3、 2007ISBN 0 580 42971 7Compliance with a British Standard cannot confer immunity from Amendments issued since publicationAmd. No. Date Comments16867 28 February 2007 Renumbers BS ISO 16862:2003 as BS EN ISO 16862:2006legal obligations.National forewordThis British Standard was published by BSI. It i

4、s the UK implementation of EN ISO 16862:2006. It is identical with ISO 16862:2003.The UK participation in its preparation was entrusted to Technical Committee STI/10, Test methods for paints.A list of organizations represented on STI/10 can be obtained on request to its secretary.This publication do

5、es not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 16862May 2006ICS 87.040English VersionPaints and varnishes - Evaluation of sag resistance (ISO16862:2003)Peintures et vernis -

6、 Evaluation de la rsistance laformation de festons (ISO 16862:2003)Beschichtungsstoffe - Bewertung der Widerstandsfhigkeitgegen Ablaufen (ISO 16862:2003)This European Standard was approved by CEN on 27 April 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipula

7、te 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 obtained on application to the Central Secretariat or to any CEN member.This European Standard exists

8、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 Secretariat has the same status as the officialversions.CEN members are the national standards bodies of

9、 Austria, Belgium, 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 United Kingdom.EUROPEAN COMMITTEE FO

10、R 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 reservedworldwide for CEN national Members.Ref. No. EN ISO 16862:2006: EForeword The text of ISO 16862:

11、2003 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 16862:2006 by Technical Committee CEN/TC 139 “Paints and varnishes“, the secretariat of which is held by DIN. This European Sta

12、ndard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 2006, and conflicting national standards shall be withdrawn at the latest by November 2006. According to the CEN/CENELEC Internal Regulations, the national

13、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, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portuga

14、l, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of ISO 16862:2003 has been approved by CEN as EN ISO 16862:2006 without any modifications. EN ISO 16862:2006INTERNATIONALSTANDARDISO16862First edition2003-11-15Reference numberISO 16862:2003(E)

15、Paints and varnishes Evaluation of sag resistancePeintures et vernis valuation de la rsistance la formation de festonsEN ISO 16862:2006ii iiiContents Page1 Scope 12 Normative references 13 Terms and definitions 24 Apparatus . 25 Sampling . 26 Test panels . 27 Procedure . 28 Expression of results 59

16、Precision . 610 Test report 6Annex A (normative) Sag index applicator blades 7Bibliography . 9EN ISO 16862:2006iv ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies(ISO member bodies). The work of preparing International Standards

17、is normally carried out through ISOtechnical committees. Each member body interested in a subject for which a technical committee has beenestablished has the right to be represented on that committee. International organizations, governmental andnon-governmental, in liaison with ISO, also take part

18、in the work. ISO collaborates closely with the InternationalElectrotechnical Commission (IEC) on all matters of electrotechnical standardization.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.The main task of technical committees is to prepar

19、e International Standards. Draft International Standardsadopted by the technical committees are circulated to the member bodies for voting. Publication as anInternational Standard requires approval by at least 75 % of the member bodies casting a vote.Attention is drawn to the possibility that some o

20、f the elements of this document may be the subject of patentrights. ISO shall not be held responsible for identifying any or all such patent rights.ISO 16862 was prepared by Technical Committee ISO/TC 35, Paints and varnishes, Subcommittee SC 9,General test methods for paints and varnishes.EN ISO 16

21、862:2006vIntroductionWhen a wet coat of paint is applied to an inclined surface, the coat will flow down the surface under its ownweight with cohesive forces opposing this flow. The balance of rheological and gravitational forces will allow acertain wet-film thickness to be applied without this unwa

22、nted flow becoming objectionable. Flow down aninclined surface is normally unstable, particularly if the coat is of uneven thickness, and it is this instability thatleads to unsightly sags and tears. For a vertical surface, the gravitational force per unit area of surface, i.e. thestress, is given b

23、y , where is the film thickness in micrometres, is the density of the coat of paintin kilograms per cubic metre and is the gravitational constant in metres per second squared. The cohesiveforce per unit area of the surface is given by , where is the Newtonian viscosity in pascal secondsand is the sh

24、ear rate in reciprocal seconds. This International Standard describes two methods fordetermining the maximum wet-film thickness of a coating which can be applied to a vertical surface withoutgiving rise to sagging or similar phenomena. The first method is carried out on a small scale using sag index

25、applicators and the second is a larger-scale, practical test.hdgh dgV d/dlVd/dlEN ISO 16862:2006blank1Paints and varnishes Evaluation of sag resistance1ScopeThis International Standard describes test methods for evaluating the sag resistance (resistance to sagging) ofpaints, varnishes and similar co

26、ating materials (coatings) when applied to a substrate and held in a verticalposition.Evaluation of the sag resistance can be carried out after the coating has been applied as follows:a) using a sag index applicator on a horizontally placed test panel which is afterwards put into a verticalposition,

27、orb) using a spray gun for application on a substrate in a vertical position.NOTE Brush or roller application can also be used provided that an even coating is applied.This International Standard is applicable to liquid coatings only.2 Normative referencesThe following referenced documents are indis

28、pensable for the application of this document. For datedreferences, only the edition cited applies. For undated references, the latest edition of the referenced document(including any amendments) applies.ISO 1513, Paints and varnishes Examination and preparation of samples for testingISO 1514, Paint

29、s and varnishes Standard panels for testingISO 1517, Paints and varnishes Surface-drying test Ballotini methodISO 2808, Paints and varnishes Determination of film thicknessISO 2884-1, Paints and varnishes Determination of viscosity using rotary viscometers Part 1: Cone-and-plate viscometer operated

30、at a high rate of shearISO 2884-2, Paints and varnishes Determination of viscosity using rotary viscometers Part 2: Disc or ballviscometer operated at a specified speedISO 3270, Paints and varnishes and their raw materials Temperatures and humidities for conditioning andtestingISO 15528, Paints, var

31、nishes and raw materials for paints and varnishes SamplingEN ISO 16862:20062 3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1 sag resistancegreatest wet-film thickness, in micrometres, of a coating, under specified conditions of application, for

32、 aspecified substrate and under specified environmental conditions, for which the coating will not have a tendencyto flow during the drying process when placed in an inclined positionNOTE 1 This flow is known as sagging.NOTE 2 Surface appearances typical of sagging are generally characterized by run

33、s, tear drops, curtains or sags.4 Apparatus4.1 Sag index applicator, with gaps of defined clearance as given in Annex A, for applying film stripes ofappropriate thickness. Examples of sag index applicators are given in Annex A.4.2 Spraying device, airless or air-assisted, for applying the coating.4.

34、3 Wet-film thickness gauge, with an appropriate range.4.4 Stirrer.5 SamplingTake a representative sample of the product to be tested, as described in ISO 15528, and prepare the samplefor testing, as described in ISO 1513.6 Test panelsUse standard panels prepared in accordance with ISO 1514.NOTE For

35、the sag index applicator method, glass panels should preferably be used to provide a flat surface over which theapplicator will lay down stripes of coating of even thickness. A sag index applicator will not run consistently over a curvedsubstrate.7 Procedure7.1 Test conditionsUnless otherwise stipul

36、ated or agreed, carry out the test under standard conditions, i.e. a temperature ofand a relative humidity of in accordance with ISO 3270.The film thickness of a coating material at which sag does not occur when applied in accordance with 7.2.3 and7.3.3 might differ. The values obtained by these met

37、hods are dependent on shear-rate at application, and thetemperature. Moisture-cure and water-thinnable coating materials are particularly influenced by the relativehumidity. The sagging tendency of two-component coatings is additionally influenced by the period betweenmixing the components and appli

38、cation.(23 2)C (50 5) %EN ISO 16862:200637.2 Using a sag index applicator7.2.1 PrincipleTwo test panels are coated with the material under test and the sag index applicator is drawn across the panels.The panels are placed vertically and the thickest stripe which shows no sign of sagging is noted on

39、each panel.The actual wet-film thickness of each stripe is measured on a third panel.7.2.2 GeneralA pre-shear programme is essential for a drawdown sag test to duplicate the breakdown in structure that occurswhen thixotropic paints are applied by brush or another practical application method. The pr

40、ocedure thereforeincludes the pre-shearing of paints just prior to application. The rate of rotation and time of stirring shall beagreed between interested parties.NOTE 1 Examples of procedures for pre-shearing are given in ASTM D 4400, which is an equivalent method using anapplicator blade.The wet-

41、film thickness obtained through application is, depending on viscosity, rheology and application speed,smaller than the gap depth of the applicator. For this reason, it is necessary to determine the actual wet-filmthickness applied and record this along with the largest gap size which does not produ

42、ces sagging.NOTE 2 If the test is being carried out for quality control purposes as a pass/fail test, then measurement of actual wet-filmthickness may not be necessary.Select a sag index applicator which will lay down a range of wet-film thicknesses which includes that specifiedfor the product being

43、 tested. It may be necessary to determine which range is most suitable by experiment.NOTE 3 For example, for a thixotropic thick film material with a sag resistance of approximately of wet film, a bladewith a maximum gap depth should be used. In the case of a polyurethane finishing paint with a flow

44、 time ofapproximately through a cup with a orifice, in accordance with ISO 2431, and a sag resistance of , a bladewith a maximum depth of will suffice.Ensure that the test panels are clean and dry. If necessary, clean with a suitable solvent and wipe dry with cleantissue or lint-free cloth.7.2.3 App

45、licationLay one test panel horizontally and secure it over a sheet of tissue paper on a firm surface.Place the sag index applicator on one end of the horizontal test panel with the clearance gaps facingdownwards.Carry out the agreed pre-shear programme (see 7.2.2) and immediately pour sufficient coa

46、ting material againstthe applicator near the edge with the clearance gaps, avoiding bubble formation. Ensure that there is sufficientpaint to enable properly formed stripes to be drawn down over a length of at least , with excess paintbeing carried to the end of the panel and on to the tissue undern

47、eath.Using a guide as necessary, immediately draw the applicator through the wet paint at a constant speed and withfirm downward pressure so that separate stripes of wet paint are cleanly formed. If stripes which are not straightor which do not have clearly defined edges are formed, discard the test

48、 panel and repeat the application on afresh panel.NOTE Examples of methods for the automated application of paint films are described in ASTM D 823.Immediately place the test panel in a vertical position with the stripes horizontal and with the smallest filmthickness at the top.Repeat the applicatio

49、n procedure on a second panel.60 m450 m60 s 4 mm 60 m150 m100 mmEN ISO 16862:20064 Using a third panel, repeat the application procedure, keeping the force and application speed constant, and,with the panel still horizontal, immediately measure the wet-film thickness at the centre of each stripe inaccordance with ISO 2808.Allow air-drying coatings to achieve the surface-dry condition in accordance with ISO 1517 under the conditionsgiven in 7.1.In the case of stoving enamels, allow the coating to flash off in accordance with th