1、BRITISH STANDARD BS3761:1995 Specification for Solvent-based paint removerBS3761:1995 This British Standard, having been prepared under the directionof the Sector Board forMaterials and Chemicals, waspublished under the authorityof the Standards Boardand comes intoeffecton 15December1995 BSI07-1999
2、First published June1964 Second edition February1970 Third edition November1986 Fourth edition December1995 The following BSI references relate to the work on this standard: Committee reference STI/3 Draft for comment94/503824DC ISBN 0 580 24535 7 Committees responsible for this British Standard The
3、 preparation of this British Standard was entrusted to Technical Committee STI/3, Paints media and related products, upon which the followingbodies were represented: British Coatings Federation Ltd. European Resin Manufacturers Association FOSFA International Ministry of Defence Oil and Colour Chemi
4、sts Association Seed Crushers and Oil Processors Association Amendments issued since publication Amd. No. Date CommentsBS3761:1995 BSI 07-1999 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Normative references 1 3 Definitions 1 4 Sampling 1 5 Performance 1 6 Marki
5、ng 2 7 Packing 2 Annex A (normative) Determination of rate of evaporation 3 Annex B (normative) Assessment of consistency 3 Annex C (normative) Assessment of relative paint removing power 4 Annex D (normative) Determination of water rinsability 6 Annex E (normative) Determination of the effect on wo
6、od 7 Annex F (normative) Determination of acidity or alkalinity 7 Annex G (normative) Determination for corrosive effects 8 Annex H (normative) Test for flammability 8 Annex J (normative) Determination of phenols in paint and varnish remover 9 Figure C.1 Apparatus for water rinsability test 5 List o
7、f references Inside back coverBS3761:1995 ii BSI 07-1999 Foreword This British Standard has been prepared by Technical Committee STI/3. It supersedes BS3761:1986 which is withdrawn. This British Standard was first published in1964 as a composition specification, which was subsequently revised in1970
8、. The latter edition reduced the number of grades specified in the1964 edition to a general-purpose product of medium consistency, but the specification continued to rely on a composition requirement. Nevertheless, in the1970 edition it was recognized that, to allow for product improvement, the spec
9、ification had to be based on performance criteria, although at that time it had not proved practicable to define a suitable reference paint surface on which to carry out a test for paint-removing properties. This was overcome, and the1986 edition included a test for assessing the paint-removing prop
10、erty. It also covered dichloromethane 1) -containing paint removers conforming to this standard. Although paint removers manufactured in accordance with this standard can be considered non-flammable in their general use, the Technical Committee responsible for this standard decided in1986 that the t
11、erm “non-flammable” should be deleted from the title of the standard. It was believed that the term could lead to laxity and abuse by users, particularly as there were no means of ensuring that containers of these paint removers were closed against loss of dichloromethane. Attention is drawn to the
12、hazards associated with the chlorinated hydrocarbons in these paint removers, and to the precautions, including the need to avoid smoking and naked flames and the necessity for good ventilation that have to be taken during their use. The water rinsability test was modified in1986 and it is emphasize
13、d to users that, after application of paint removers conforming to this standard, it is essential to wash the surface thoroughly free from waxy and other residues. These residues comprise constituents of the paint remover, which will, if left on the surface, inhibit the drying of a subsequent paint
14、coating. Solvents other than water may be used to wash the surface, but the hazards associated with these solvents have to be considered before their use in confined areas. Paint removers conforming to this standard are not considered suitable for use on items where attack of metals, caused by react
15、ion between the metal and the paint remover, is regarded as critical (e.g.metallic surfaces of aircraft and electronic equipment). Furthermore, a number of plastics surfaces may also be seriously affected by constituents of these paint removers. After application to a painted surface, the paint remo
16、ver is allowed to remain undisturbed until the paint film has become softened, swollen or blistered overall. It is subsequently removed, together with the affected paint film, by scraping, followed by washing with water or a suitable solvent, such as white spirit, or a solvent compatible with the co
17、ating system to be applied. More than one application of the paint remover may be necessary. Certain types of coating, such as some stoving, cold-cured or polymeric materials, may not be readily acted upon by these paint removers. For the removal of such special coatings, or if the substrate is atta
18、cked by constituents of the paint removers, manufacturers should supply removers appropriate to the specific case, although these would not necessarily conform to this standard. In the drafting of this British Standard it has been assumed that the tests described in this standard will be used by tho
19、se who are appropriately qualified and experienced. 1) Dichlormethane is commonly known as methylene chloride.BS3761:1995 BSI 07-1999 iii WARNING NOTE. Paint removers conforming to this standard contain dichloromethane. Particular attention is drawn to the hazards associated with dichloromethane, wh
20、ich is classified as harmful by inhalation, by contact with the skin or if swallowed; it is also classified as a class3 carcinogen with the possible risk of irreversible effects. It is essential that products containing this material are packaged in accordance with current national regulations. A Br
21、itish 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. Summary of pages This document comprises a fr
22、ont cover, an inside front cover, pagesi toiv, pages1to10, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.iv blankBS3761:1995 BSI 07-1999 1 1
23、Scope This British Standard specifies requirements for solvent-based paint removers applied by brush. The paint removers are intended for general use on surfaces of painted, varnished or lacquered wood, plaster or metal. As supplied, paint removers conforming to this standard will be non-flammable a
24、nd will not be suitable for some substrates (seeforeword). 2 Normative references This British Standard incorporates, by dated or undated reference, provisions from other publications. These normative references are made at the appropriate places in the text and the cited publications are listed on
25、the inside back cover. For dated references, only the edition cited applies; any subsequent amendments to or revisions of the cited publication apply to this British Standard only when incorporated in the reference by amendment or revision. For undated references, the latest edition of the cited pub
26、lication applies, together with any amendments. 3 Definitions For the purposes of this British Standard, the definitions given in BS2015 apply together with the following. paint remover at a temperature of23 C 2 C, a homogeneous liquid based on dichloromethane, together with agents to give the requi
27、red consistency, to confer miscibility with water and to limit the rate of evaporation, used to remove paint NOTEPaint remover may also contain corrosion inhibitors. 4 Sampling Representative samples to give a test sample of not less than1000ml of the product shall be taken and stored in accordance
28、with BS EN21512. 5 Performance NOTEWhen carrying out the tests referred to in5.1 to5.8, the precautions given in the warning note in the introduction should be observed. 5.1 Rate of evaporation When tested in accordance withAnnex A, the product shall not lose more than2% (m/m) by evaporation. NOTEIt
29、 is advised that this test is carried out immediately after opening the container for the first time. 5.2 Consistency When tested in accordance withAnnex B, the product shall have a viscosity of not less than0.3Pas 2)and not more than0.5Pas. This shall be indicated by observing the rate of rise of t
30、he bubble seeB.4 b). NOTEFor products for special purposes, it may be necessary to specify other viscosities. These products do not conform to this standard. 5.3 Paint-removing power When tested in accordance withAnnex C, the product shall not be inferior to the reference paint remover (seeC.3.3) us
31、ing the following criteria: a) the average time taken for the paint, applied to either of the test panels, to wrinkle or lift shall not exceed that of the reference paint remover; b) after subjection to the washing procedure (seeC.5.5), the squares treated with the product under test shall retain no
32、 more of the applied reference paints than the squares treated with the reference paint remover. 5.4 Water rinsability When tested in accordance withAnnex D, any residue left on the panel by the product shall be not more than0.5% (calculated as a percentage of the mass of paint remover applied). The
33、 residue shall be easily and completely removed by brushing under water and, after drying, the panel shall be in a suitable condition to accept a coat of the reference primer. The treatment, by comparison with the reference panel, shall impair neither the surface-dry properties of the primer when te
34、sted in accordance with the method given in BS3900-C2, nor the appearance of the dried film. 5.5 Effect on wood When tested in accordance withAnnex E, staining of the substrate shall not exceed that shown on the reference panel. The substrate shall be in a suitable condition to accept a coat of the
35、reference primer and the treatment shall impair neither the surface-dry properties of the primer nor the appearance of the dried film as compared with the reference panel. 5.6 Acidity or alkalinity When tested in accordance withAnnex F, the product shall not: a) be acidic to the methyl orange indica
36、tor; b) contain more than0.08% (m/m) of alkalinity, calculated as sodium hydroxide. 2) Pas=1Ns/m 2 =10P.BS3761:1995 2 BSI 07-1999 5.7 Corrosive effects When tested in accordance withAnnex G, the product shall not cause visible rusting or corrosion of the steel test piece and the mass of the test pie
37、ce shall not be increased by more than1mg nor decreased by more than5mg. 5.8 Flammability NOTEAttention is drawn to the Highly Flammable Liquids and Liquefied Petroleum Gas Regulations19721. When tested in accordance withAnnex H, the product shall not burn over the whole surface of any of the test p
38、anels and shall not burn for more than2s after removal of the flame following any of the five applications. 5.9 Storage properties When stored at a temperature above3 C and not exceeding23 C in the sealed original containers, the product shall be in accordance with5.1 to5.8 for a period of not less
39、than24 months from the date of manufacture. When stored at a temperature above0 C and not exceeding32 C, the product shall be in accordance with5.1 to5.8 for a period of not less than12months from the date of manufacture. 5.10 Phenol content When tested in accordance withAnnex J, the product shall n
40、ot contain more than0.2% (m/m) of phenols expressed as C 6 H 5 OH. 6 Marking Containers in which the product is packed shall be legibly and indelibly marked with the following: a) the manufacturers name or trade mark; b) the number and date of this British Standard, i.e.BS3761:1995 3) ; c) general p
41、recautions, i.e.warning and first-aid advice; d) instructions for use; e) the batch number; f) the date of manufacture; g) any additional labelling required by national legislation for this type of product. 7 Packing The product shall be packed into sound, clean and dry containers which shall be sea
42、led with a screw cap. If glass bottles are used, these shall have a capacity not greater than250ml. NOTEIt is recommended that containers should be of sufficient strength to withstand any pressure likely to develop internally during storage under normal conditions. Ullage should be provided to avoid
43、 undue pressure developing inside the container when it is stored under normal conditions. 3) Marking BS3761:1995 on or in relation to a product represents a manufacturers declaration of conformity, i.e.a claim by or on behalf of the manufacturer that the product meets the requirements of the standa
44、rd. The accuracy of the claim is solely the claimants responsibility. Such a declaration is not to be confused with third party certification of conformity, which may also be desirable.BS3761:1995 BSI 07-1999 3 Annex A (normative) Determination of rate of evaporation A.1 Apparatus A.1.1 Ordinary lab
45、oratory apparatus A.1.2 Glass dish, of approximately75mm internal diameter and10mm wall height. NOTEThe lid of a Petri dish may be used. A.1.3 Hypodermic glass syringe, of10ml capacity, but without a needle. A.1.4 Balance, capable of weighing to an accuracy of1mg or less. A.2 Procedure A.2.1 Carry o
46、ut the procedure in a room controlled at a temperature of23 C 2 C. Place the sealed container containing the product under test in the room at least16h before testing. NOTEThis test should be carried out on a sample removed from a previously unopened container. A.2.2 Weigh the glass dish (A.1.2) to
47、the nearest1mg. A.2.3 With the top pointing away, carefully open the container to release any excess pressure. Immediately close the container and then gently invert it to ensure the homogeneity of the product under test. Cautiously re-open the container and quickly transfer a sample of approximatel
48、y50ml into a100ml squat beaker. Fill the syringe(A.1.3) with more than10ml of the sample in the beaker at a rate of about1ml/s, maintaining the syringe opening approximately5mm below the surface of the sample. Invert the syringe and expel the excess liquid until the volume of the product in the syri
49、nge is10ml. Take care to expel any bubbles. Wipe off any excess of sample from the outside of the syringe and weigh the filled syringe to the nearest1mg. A.2.4 Expel the contents of the syringe at a rate of about1ml/s into the centre of the glass dish(A.1.2) placed on a horizontal surface exposed to the air but protected from draughts. Reweigh the syringe. After30min1min, reweigh the dish and its contents to the nearest1mg. A.3 Calculation The loss in mass %m L(in%) is given by the equation: Annex B (normative) Assessment of consistency B.1 Princip
