1、BRITISH STANDARD BS 388:1972 Specification for Aluminium pigmentsBS388:1972 This British Standard, having been approved by the Pigments, Paints and Varnishes Industry Standards Committee, was published under the authority ofthe Executive Board on 16 May 1972 BSI 12-1999 First published August 1930 F
2、irst revision November 1938 Second revision December 1952 Third revision May 1964 Fourth revision May 1972 The following BSI references relate to the work on this standard: Committee reference PVC/1/19 Draft for approval 71/50728 ISBN 0 580 07361 0 Co-operating organizations The Pigments, Paints and
3、 Varnishes Industry Standards Committee, under whose supervision this British Standard was prepared, consists of representatives from the following Government departments and scientific and industrial organizations: British Colour Makers Association British Railways Board Chemical Industries Associa
4、tion Crown Agents for Oversea Governments and Administrations Department of the Environment Department of Trade and Industry Department of Trade and Industry, Laboratory of the Government Chemist Greater London Council London Transport Executive Ministry of Defence, Army Department* Ministry of Defe
5、nce, Navy Department National Federation of Builders and Plumbers Merchants Oil and Colour Chemists Association Paint Manufacturers and Allied Trades Association Paintmakers Association of Great Britain Ltd.* Post Office Research Association of British Paint, Colour and Varnish Manufacturers* Royal
6、Institute of British Architects Royal Institute of Public Health and Hygiene Society of Chemical Industry Titanium Pigment Manufacturers Technical Committee White Lead Manufacturers Association Zinc Development Association Zinc Pigment Development Association The Government department and scientific
7、 and industrial organizations marked with an asterisk in the above list, together with the following, were directly represented on the committee entrusted with the preparation of this British Standard: Aluminium Federation Amalgamated Society of Painters and Decorators Decorators of England and Wale
8、s National Federation of Master Painters Amendments issued since publication Amd. No. Date CommentsBS388:1972 BSI 12-1999 i Contents Page Co-operating organizations Inside front cover Foreword ii 1 Scope 1 2 Sampling 1 3 Agreed sample 1 4 Description 1 5 Classification 1 6 Required characteristics a
9、nd their tolerances 2 7 Packing 2 Appendix A Method for the determination of matter soluble in organic solvents 3 Appendix B Method for the comparison of appearance 4 Appendix C Method for the determination of residue on sieve 4 Appendix D Method for the determination of water-covering capacity 5 Ap
10、pendix E Method for the determination of leafing power 7 Appendix F Test for absence of leafing power 9 Appendix G Method for the determination of water content 9 Appendix H Methods for the determination of metallic impurities 10 Figure 1 Suitable sampling tubes 12 Figure 2 Trough for determination
11、of water-covering capacity 13 Figure 3 Examples of measurement of leafed area 14 Table 1 Classification of materials 1 Table 2 Required characteristics and their tolerances 2 Table 3 Test portions for leafing test 8BS388:1972 ii BSI 12-1999 Foreword This standard makes reference to the following Bri
12、tish Standards: BS 245, White spirit. BS 410, Test sieves. BS 1728, Methods for the analysis of aluminium and aluminium alloys Part 5: Determination of copper (absorptiometric method) Part 8: Determination of iron (absorptiometric 1:10 phenanthroline method) Part 10: Determination of manganese (abso
13、rptiometric method) Part 12 Silicon (absorptiometric molybdenum blue method) Part 18 Method for the determination of zinc (ion-exchange-volumetric EDTA or polarographic method). BS 1752, Laboratory sintered or fritted filters. BS 2511, Methods for the determination of water (Karl Fischer method). BS
14、 3483, Methods for testing pigments for paints. BS 3978, Water for laboratory use. BS 4726, Sampling raw materials for paints and varnishes. The British Standard for aluminium pigments was first issued in1930and was subsequently revised in1938,1952and1964. The present revision is technically identic
15、al with ISO/R1247, “Aluminium pigments”, except that in this standard there is an additional requirement that the leafing power of the leafing material shall be not less than90% of that of the agreed sample. NOTEThe use of chlorinated hydrocarbon solvents with aluminium powder or paste can be hazard
16、ous if heating is involved, since a rapid exothermic reaction may take place. Experience has shown, however, that chloroform presents no danger when used as described inAppendix G. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards a
17、re 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 front cover, an inside front cover, pages i and ii, pages1 to 14 and a back cover. This standard has been updated (se
18、e copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS388:1972 BSI 12-1999 1 1 Scope This British Standard specifies the requirements and the corresponding methods of test for aluminium pigments used in paints including
19、1) general purpose, decorative and protective paints, and 2) speciality finishing paints. NOTEThe titles of the British Standards referred to in this standard are listed on pageii. 2 Sampling For the purposes of testing a pigment in accordance with this standard, a sample representative of the bulk
20、material shall be taken by an appropriate procedure, as described in BS4726. The sample shall not be less than250g in mass. For both pastes and powders a sampling tube should be used that enables the whole depth of the container to be sampled (and preferably, the longest diagonal of the container).
21、For powders, which may be compacted, a sharply pointed sampling tube should be used, and the container should be rolled vigorously before sampling. Suitable designs of sampling tubes are illustrated inFigure 1. 3 Agreed sample Except where otherwise agreed between the purchaser and the vendor, the a
22、greed sample referred to in Table 2 shall comply in all respects with the requirements of this standard. The mass of the sample shall be not less than 250 g and shall be packed in the manner described in BS4726. 4 Description The material shall be composed essentially of finely divided aluminium met
23、al. The particles of aluminium metal shall be lamellar, which can be confirmed by microscopical examination. The material shall be in the form of a powder or a homogeneous paste. NOTEMica and other adulterants shall be absent. If when preparing a solution of the sample in hydrochloric acid inH.1.3.3
24、 a non-fatty residue is obtained, the residue should be examined further. 5 Classification 5.1 Types. This British Standard covers four types of aluminium pigments, as follows: Type 1. Aluminium powder, leafing Type 2. Aluminium paste, leafing Type 3. Aluminium powder, non-leafing Type 4. Aluminium
25、paste, non-leafing 5.2 Classes. Pigments of Types1 and2 are further classified by their water-covering capacity as shown inTable 1. Table 1 Classification of materials NOTEAttention is drawn to the reproducibility limits given inD.6.2. Type Class Water-covering capacity m 2 /g 1 a up to 0.8 b over 0
26、.8 up to 1.5 c over 1.5 up to 2.2 d over 2.2 p up to 1.7 2 q over 1.7 up to 2.4 r over 2.4BS388:1972 2 BSI 12-1999 6 Required characteristics and their tolerances The material shall have the characteristics given in the appropriate column ofTable 2. The liquid contained in paste pigment shall be whi
27、te spirit complying with the requirements of BS245, or other appropriate liquid as may be agreed between the purchaser and the vendor. 7 Packing The material shall be packed in air-tight containers. Table 2 Required characteristics and their tolerances Type Type 1 leafing powder Type 2 leafing paste
28、 Type 3 non-leafing powder Type 4 non-leafing paste Test method Matter volatile at105 C,% max. 1.0 35.0 a 1.0 35.0 a BS 3483 Matter soluble in organic solvents, % max. 6.0 4.0 1.5 6.0 Appendix A (Types1 and 2, Method 1; Types 3 and 4, Method 2) Appearance of paint prepared in an agreed vehicle To ma
29、tch closely the appearance of paint prepared similarly from the agreed sample Appendix B Residue on sieve b Nil on 250 4m Nil on 180 4m Nil on 2504m Nil on 1804m Appendix C Water-covering capacity m 2 /g Within the limits for the agreed class (see clause5) Appendix D leafing power 65 % min. andnot l
30、ess than 90 % of that of the agreed sample 65 % min. andnot less than 90 % of that of the agreed sample Nil Nil Appendix E (Types 1 and 2) Appendix F (Types3 and 4) Water content, %max. 0.2 0.15 0.2 0.15 Appendix G Metallic impurities, % max., on dry pigment 1.0 for Cu + Fe + Pb + Si + Zn. 0.03 for
31、Pb. Separate limits for metals other than lead may be agreed between the purchaser and the vendor. Limits to be agreed between the purchaser and the vendor. Appendix H a Alternative limits for volatile content of pastes may be agreed between the purchaser and the vendor. b Additional limits for resi
32、due on sieves of smaller apertures may be agreed between the purchaser and the vendor.BS388:1972 BSI 12-1999 3 Appendix A Method for the determination of matter soluble in organic solvents A.1 Method 1 (for use with leafing pigments, Types 1 and 2) A.1.1 Principle. The sample is treated with hydroch
33、loric acid to dissolve the metal and the residual oily and fatty matter is extracted with acetone and weighed. A.1.2 Reagents. The reagents used shall be of recognized analytical quality. Water that complies with the requirements of BS3978 shall be used. 1) Hydrochloric acid solution, approximately
34、6N. 2) Acetone. A.1.3 Procedure A.1.3.1 Test portion. Weigh, to the nearest milligram, about2g of the test sample into a400ml beaker. A.1.3.2 Determination. Add100ml of hot water to the test portion and cover the beaker,e.g.with a watch glass. Add the hydrochloric acid in small portions, heating gen
35、tly to complete the reaction after each addition until all the metal is dissolved. Not more than60ml of acid should be required. Cool the beaker and contents to room temperature and filter the contents through an acid-washed, grease-free filter paper. Thoroughly wash the beaker, the cover and the fi
36、lter paper with cold water. Allow the paper to drain and dry completely in the filter funnel, heating gently, if necessary, to a temperature not exceeding50 C. Remove as much water as possible from the beaker by shaking it. Place a weighed100ml beaker under the funnel. Wash the original beaker and c
37、over with warm acetone and transfer the washings to the filter paper. Wash the paper at least five times with warm acetone filling it about half full each time. Finally, rinse the tip of the funnel. Gently warm the beaker and its contents on a water-bath without using a free flame, until the acetone
38、 has been evaporated as completely as is possible. Continue the evaporation by heating the beaker at a temperature of105 2 C for1h, cool and weigh. A.1.4 Calculation. Calculate the matter soluble in organic solvents, as a percentage by mass, by means of the following formula: A.2 Method 2 (for use w
39、ith non-leafing pigments, Types 3 and 4) A.2.1 Principle. The sample is dispersed in solvent and the solvent extractable matter is filtered off, dried and weighed. A.2.2 Apparatus. Sintered glass filter crucible, of porosity Grade4 that complies with the requirements of BS1752. A.2.3 Reagents 1) Sol
40、vent mixture. Mix3 parts by volume of toluene with1part of diethyl ether, d =0.720. 2) Light petroleum, boiling range of from40to60 C. A.2.4 Procedure A.2.4.1 Test portion. Weigh, to the nearest milligram, about2g of the test sample into a250ml beaker and disperse it in20ml of the solvent mixture, w
41、ith frequent intermittent swirling of the contents of the beaker. A.2.4.2 Determination. When complete dispersion has been obtained add a further10ml of the solvent mixture, thoroughly agitate by swirling the beaker and then allow to stand for1h to enable the metallic flakes to settle. Decant the su
42、pernatant liquid into the sintered glass filter crucible and filter by suction into a clean flask. When all the liquid has been filtered, add a further30ml of the solvent mixture to the residue in the beaker and repeat the swirling so as to redisperse the aluminium pigment. Filter the dispersion thr
43、ough the sintered glass filter crucible, washing the beaker with the light petroleum spirit. where m = mass of test portion (g) m 1= mass of residue (g). 100 m 1 m -BS388:1972 4 BSI 12-1999 Transfer the filtrate from the flask to a250ml beaker and evaporate to minimum bulk (about50ml). Transfer the
44、concentrated filtrate to a tared 100ml beaker and wash the250ml beaker with the light petroleum, transferring the washings into the100ml beaker. Evaporate the contents of the100ml beaker just to dryness, heat in an oven at a temperature of105 2 C for1h, then cool and weigh. A.2.5 Calculation. Calcul
45、ate the matter soluble in organic solvents, as a percentage by mass, by means of the following formula: Appendix B Method for the comparison of appearance B.1 Procedure B.1.1 Test portion. Weigh an amount of test sample that has been agreed between the purchaser and the vendor. B.1.2 Assessment. Dis
46、perse the test portion in a paint vehicle to be agreed between the purchaser and the vendor (see Note) in the agreed proportions, by simple mixing without grinding. Store in a covered container for a period to be agreed between the purchaser and the vendor, e.g.24h at a temperature also to be agreed
47、, preferably20 C. After this period remove any surface skin, mix well by shaking or stirring, or both, and apply a coat of the mixture by a suitable method to a smooth, clean, non-absorbent panel, and allow to dry thoroughly in a clean atmosphere. Treat the agreed sample in a similar way on the same
48、 day. When dry, compare visually the two panels for colour, opacity, finish and brightness. NOTEFor leafing pigments, the vehicle should have an acid value less than7.5mg of KOH per gram and should not contain lead driers. Appendix C Method for the determination of residue on sieve C.1 Apparatus The
49、 following apparatus is required. 1) Containers, 3, of suitable size to accommodate the sieve. 2) Beaker, 400ml. 3) Test sieve of nominal aperture1804m (for pastes) or2504m (for powders) complying with BS410 (see Note toC.3.1). 4) Sintered glass filter, of porosity Grade4that complies with the requirements of BS1752. C.2 Reagents The following reagents are required. 1) White spirit, complying with the requirements of BS245. 2) Acetone, of recognized commercial quality. C.3 Procedure C.3.1 Test portion. Weigh10g o
