1、Designation: D 3928 00a (Reapproved 2005)Standard Test Method forEvaluation of Gloss or Sheen Uniformity1This standard is issued under the fixed designation D 3928; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last r
2、evision. 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 test method covers the determination of the unifor-mity of gloss or sheen of a paint applied by brush to a test panels
3、imulating an interior wall section. Variations in gloss or sheenthat may be caused by short wet edge time, poor leveling, andpigment orientation or flotation during and after application areevaluated visually.1.2 Because both the application and the panel evaluationare very subjective, this test met
4、hod should be used only forcomparative testing within one laboratory as the ratings as-signed by different laboratories do not usually agree (see 8.1).1.3 The values given in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.4 This standard does no
5、t 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 applica-bility of regulatory limitations prior to use.2. Summary of Test Method2.1 Paint is br
6、ush applied to a test panel using proceduresand conditions that are most likely to cause nonuniformity ofgloss or sheen. The dry film is then viewed under conditionsthat accentuate variations in gloss or sheen and the overallappearance is evaluated.3. Significance and Use3.1 When coatings are applie
7、d to large flat surfaces such aswalls, the film thickness may vary or there may be small areasmissed entirely (holidays) when the color of the fresh materialand the previous film are very similar. It is much less costly ifthese areas can be touched up instead of having to repaint theentire surface.3
8、2 Thickness is also affected in the locations where an areacoated a short time before is joined with the area currentlybeing coated (laps). An application technique that may affectthe final appearance of the film is brushing or rolling thematerial in different directions in adjacent areas.3.3 Both
9、buyers and sellers are interested in determiningwhether a coating can be applied without exhibiting areas thatdiffer in appearance because of laps and brush or roller marks,and whether it can be readily touched up to provide a uniformappearance in regard to gloss or sheen and all other aspects.4. Ap
10、paratus4.1 Paint Brush2, 50 mm (2 in.) wide with polyesterfilaments 70 mm (234 in.) long, chisel tip 15 mm (916 in.) thick.Previously used brushes are preferred.4.2 Paint Brush, 25 mm (1 in.) wide with polyester fila-ments 57 mm (214 in.) long, chisel tip 10 mm (716 in. ) thick.Previously used brush
11、es are preferred.5. Reagents and Materials5.1 Laminated Fiber Board, 610 by 300 mm (24 by 12 in. )with at least one smooth side.5.2 Latex-Base Primer.35.3 Control Paint (optional)Since there are no standardpanels, photographs, or paints for this test method, an agreed-upon paint of known uniformity
12、of appearance should beincluded with the test paints as a control, unless the paints areonly ranked.6. Procedure6.1 Apply the latex primer by spray to the entire face of asmooth side of the test panel so as to coat it uniformly at aspreading rate of about 11 m2/gal/L (450 ft2).6.2 Air dry at least 1
13、8 h under standard conditions of 23 62C (73.5 6 3.5F) and 50 6 5 % relative humidity andexamine the panel for uniformity of primer application. If thisappears satisfactory, divide the coated area into sections A andB as shown in Fig. 1.6.3 Mount the panel vertically and position it as shown inFig. 1
14、 with Section A to the right and Section B to the left ofthe operator. Before painting, wet the brush with water if latexpaints are to be tested or VM sheen uniformity; touch-upASTM International takes no position respecting the validity of any patent rights asserted in connection with any item ment
15、ionedin 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 standard is subject to revision at any time by the responsible technical committee
16、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 International Headquarters. Your comments will receive careful consideration at a meeting
17、 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 below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO B
18、ox 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 3928 00a (2005)3
