1、Designation: D 4708 99 (Reapproved 2004)Standard Practice forPreparation of Uniform Free Films of Organic Coatings1This standard is issued under the fixed designation D 4708; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、 of last revision. A number 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 practice covers the preparation of free films oforganic coatings for use in determining the physical propert
3、iesof the coatings. Procedures are given for preparing free filmson four alternative substrates. These substrates are dental foil,treated FEP (fluorinated ethylene-propylene) sheet, siliconecoated paper, and halo-silane coated glass plates.1.2 The values stated in SI units are to be regarded as thes
4、tandard. The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the appl
5、ica-bility of regulatory limitations prior to use. A specific hazardstatement is given in 6.1.2. Referenced Documents2.1 ASTM Standards:2D 823 Practices for Producing Films of Uniform Thicknessof Paint, Varnish, and Related Products on Test PanelsD 1005 Test Methods for Measurement of Dry-Film Thick
6、-ness of Organic Coatings Using MicrometersD 1653 Test Methods for Water Vapor Transmission ofOrganic Coating FilmsD 2370 Test Method for Tensile Properties of OrganicCoatings3. Summary of Test Method3.1 Free films are prepared by depositing a uniform wetcoating of the test material on a release sub
7、strate. The appliedfilms are dried or baked, cut into appropriate size for theintended physical property test, and then stripped from therelease substrate.4. Significance and Use4.1 Free films are required for conducting tests to evaluatephysical properties such as tensile and elongation (Test Metho
8、dD 2370), moisture vapor permeability (Test Methods D 1653),and other physical properties of organic coatings where thesubstrate may interfere with the determination.4.2 The tin foil/mercury amalgamation procedure should beused only in cases where other substrates may be affected byhigh-temperature
9、baking or may affect the test results.5. Apparatus and Materials5.1 Equipment, for applying films of uniform thickness asdescribed in Practices D 823.5.2 Micrometer Film Thickness Gage, as described in TestMethods D 1005.5.3 Alternative Release Substrates:5.3.1 Dental Tin Foil, preferably 25-m (1-mi
10、l) thick.5.3.2 Sheet of FEP(polyhexafluoropropylene),3prefer-ably 50-m (2-mils) thick, coated with a thin film of a drylubricant.45.3.3 Sheet of Silicone Coated Paper, preferably 125-m(5-mil) thick.55.3.4 Glass Plates, coated with halosilane compound.NOTE 1Other substrates that may be suitable are 2
11、50-m (10-mil)thick polyethylene, photographic paper, polished steel, and fluoropolymercoated metal panels.1This practice is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.23 on Physical Proper
12、ties of Applied Paint Films.Current edition approved June 1, 2004. Published June 2004. Originallyapproved in 1987. Last previous edition approved in 1999 as D 4708 99.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual
13、 Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Teflon FEP 2-mil film thickness (Card No. 03111, Item #29499) from E.I. duPont de Nemours film; halosilane coated glassplates; lacquer; organic coatings; paints and related coatings;polyhexafl
14、uoropylene (FEP) substrate; silicone-coated paper;substrates; surface preparation; tension (tensile) properties/tests; vapors; varnishes6The sole source of supply of the JDC Precision Sample Cutter, known to thecommittee at this time is the Thwing-Albert Instrument Co., 10960 Dutton Rd.,Philadelphia
15、, PA 19154. If you are aware of alternative suppliers, please provide thisinformation to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee,1whichyou may attend.D 4708 99 (2004)2ASTM International takes no position res
16、pecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This
17、standard is subject to revision at any time by the responsible technical committee and must be reviewed every five 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 Intern
18、ational Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown be
19、low.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 4708 99 (2004)3
