1、Designation:D 237 57(Reapproved 1997)Standard Specification forOrange Shellac and Other Lacs1This standard is issued under the fixed designation D 237;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number
2、 in parentheses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers three types and four grades oforange shellac and other lac,as follows:1.1.1 Type I,orange shallac,grades A,B,C,and D,1
3、.1.2 Type II,button lac,and1.1.3 Type III,garnet lac.1.2 Stick-lac and seed-lac are not covered by this specifica-tion.2.Referenced Documents2.1 ASTM Standards:D 29 Test Methods for Sampling and Testing Lac Resins23.Physical Properties3.1 The material shall conform to the requirements pre-scribed in
4、 Table 1.NOTE1Type II customarily occurs in the form of circular disks about3 in.(76 mm)in diameter and18in.(3.2 mm)in thickness and is knownto the trade as pure button lac.Type III is dark garnet in color and isknown to the trade as pure garnet lac.Garnet lac also is manufactured inadmixture with r
5、osin and as a dewaxed lac,but these are not covered bythis specification.4.Test Methods4.1 The material shall be sampled and the properties enu-merated in this specification shall be determined in accordancewith Test Methods D 29.5.Keywords5.1 lac;orange shellac;shellac1This specification is under t
6、he jurisdiction of ASTM Committee D-1 on Paintand Related Coatings Materials and Applications and is the direct responsibility ofSubcommittee D01.33 on Polymers and Resins.Current edition approved Sept.30,1957.Published November 1957.Originallypublished as D237 26.Last previous edition D237 55.2Annu
7、al Book of ASTM Standards,Vol 06.03.1Copyright ASTM,100 Barr Harbor Drive,West Conshohocken,PA 19428-2959,United States.The American Society for Testing and Materials takes no position respecting the validity of any patent rights asserted in connectionwith any item mentioned in this standard.Users o
8、f this standard are expressly advised that determination of the validity of any suchpatent rights,and the risk of infringement of such rights,are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five
9、years andif not revised,either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM Headquarters.Your comments will receive careful consideration at a meeting of the responsibletechnical committee,which you
10、may attend.If you feel that your comments have not received a fair hearing you should make yourviews known to the ASTM Committee on Standards,at the address shown below.This standard is copyrighted byASTM,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA19428-2959,United States.Individual repri
11、nts(single or multiple copies)of this standard may be obtained by contacting ASTM at the above address or at610-832-9585(phone),610-832-9555(fax),or serviceastm.org(e-mail);or through the ASTM website(www.astm.org).TABLE 1 Requirements for Orange Shellac and Other LacsType IType IIType IIIGrade AGra
12、de BGrade CGrade D.Matter insoluble in specified hot solvents,max,%1.001.251.503.001.000.50Iodine number,max15.015.015.015.015.018.0Moisture,max,%2.02.02.02.02.02.0Wax,max,%5.55.55.55.55.53.5Orpiment,max,%0.030.030.030.20.030.03Matter soluble in water,max,%0.50.50.50.50.50.5Ash,max,%1.01.01.01.00.50
13、.5Rosinnonenonenonenonenone.Colorwhen specified,the color shall be no darker than that of a sample agreed upon between the seller and thepurchaserAAAttention is called to the fact that the seller and the purchaser must agree upon one of the two methods for determining color appearing in Test Methods D 29.D 2372
