1、Designation: D1640/D1640M 14 (Reapproved 2018)Standard Test Methods forDrying, Curing, or Film Formation of Organic Coatings1This standard is issued under the fixed designation D1640/D1640M; the number immediately following the designation indicates theyear of original adoption or, in the case of re
2、vision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 These test m
3、ethods cover the determination of thevarious stages and rates of film formation in the drying orcuring of organic coatings under laboratory controlled condi-tions of air temperature, (low, ambient and/or elevated) and/orhumidity. Procedures for assessing drying under prevailingconditions of temperat
4、ure and humidity in the shop and fieldare also described.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalue
5、s from the two systems may result in non-conformancewith the standard.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, health, and environmental practices a
6、nd deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom
7、-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D823 Practices for Producing Films of Uniform Thicknessof Paint, Coatings and Related Products on Test PanelsD4414 Practice for Measurement of Wet Film Thickness b
8、yNotch Gages2.2 ISO Standards:3ISO 91174 Paints and varnishes Determination of drying Part 4: Method using a mechanical recorder3. Significance and Use3.1 These test methods can be used to determine the variousstages and rates of drying, curing, and film formation oforganic coatings for comparing ty
9、pes of coatings, assessing theimpact of compositional changes on drying time, or forassessing drying/curing time in the shop or field. Low tem-perature can significantly slow the drying rate of coatings solow temperature curing agents, catalysts and/or accelerators areoften available to aid drying a
10、nd film formation under coolertemperatures. Method B is designed to evaluate these compo-nents and/or to determine the effect of cooler temperatures ondrying rates. Conversely, the drying/curing rate of certaincoatings can be accelerated under elevated temperature/humidity conditions, while others m
11、ay be adversely impactedby elevated humidity. Method C is designed to evaluate theeffects of elevated temperature and relative humidity condi-tions on drying, curing, and film formation of paints andcoatings. The terms dry or drying, cure or curing, and filmformation are used interchangeably through
12、out this standard.3.2 Test Methods A, B and C are limited to a comparison ofpaints/coatings applied to smooth, non-absorbent substratesand do not reflect the effect of absorption of the paint vehicleinto the substrate material.4. Substrate, Coating Application Method and FilmThicknesses4.1 Obtain ag
13、reement between the contracting parties as tothe substrate, wet film thickness (WFT), and applicationmethod for testing the specific coating involved. The product istested as manufactured (without reducer, unless otherwiseagreed upon by contracting parties). Unless otherwise agreed,the thickness of
14、the cast film shall conform to the coatingmanufacturers product data sheet. If the wet film thickness isnot stated on the manufacturers product data sheet, it can be1These test methods are under the jurisdiction of ASTM Committee D01 onPaint and Related Coatings, Materials, and Applications and are
15、the directresponsibility of Subcommittee D01.23 on Physical Properties of Applied PaintFilms.Current edition approved Sept. 1, 2018. Published September 2018. Originallyapproved in 1959. Last previous edition approved in 2014 as D1640 14. DOI:10.1520/D1640_D1640M-14R18.2For referenced ASTM standards
16、, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New
17、 York, NY 10036, http:/www.ansi.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Pr
18、inciples for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1calculated using the formula in 4.1.1 based on the manufac-turers recommended dry film thickness (DFT) and percentnon-volatile by vol
19、ume (% solids by volume). If this informa-tion is not provided, contact the coating manufacturer to obtainthe recommended wet film thickness for testing.4.1.1 WFT5 DFT % Solids by Volume !5. Test Conditions5.1 Method A (Laboratory ProcedureNormal DryingConditions):5.1.1 Conduct all drying tests in a
20、 well-ventilated room orchamber, free from direct drafts, dust, products of combustion,laboratory fumes and under diffused light (see 5.1.4). Make allmeasurements at an air temperature of 23 6 2C and 50 6 5%relative humidity with the coated panels in a horizontalposition while drying.5.1.2 Apply the
21、 wet film according to the coating manufac-turers instructions. In the absence of any specific materialspecification or product data sheets, instructions for casting thefilm should be agreed upon between contracting parties.5.1.3 Films to be tested should have practical thicknessescommensurate with
22、the coating manufacturers recommenda-tions.All testing should be performed within an area at least 15mm 12 in. from any film edge.5.1.4 Illumination of the films during the entire drying testperiod must be from low, non-radiant energy light sources,such as normal laboratory or sky sources, never fro
23、m directsunlight.5.2 Method B (Laboratory ProcedureLow Air Tempera-ture Drying Conditions):5.2.1 Conduct all drying tests in a ventilated temperatureand humidity-controlled chamber. Allow the temperature andrelative humidity to stabilize within the chamber prior to use.5.2.2 Condition the substrate
24、material, the coating to betested, and the application device for a minimum of1hinthetemperature/humidity-controlled chamber prior to casting thewet film.5.2.3 Make all measurements at a temperature and relativehumidity as agreed upon between contracting parties. Recordthe actual temperature and rel
25、ative humidity employed fortesting. All dry time measurements are made with the coatedpanels in a horizontal position while drying.5.2.4 Apply the wet film according to the coating manufac-turers instructions. In the absence of any specific materialspecification or product data sheets, instructions
26、for casting thefilm should be agreed upon between contracting parties.5.2.5 Films to be tested should have practical thicknessescommensurate with the coating manufacturers recommenda-tions.All testing should be performed within an area at least 15mm 12 in. from any film edge.5.2.6 Minimize opening a
27、nd closing of the temperature andhumidity-controlled chamber to prevent fluctuations in condi-tions.5.3 Method C (Laboratory ProcedureElevated Air Tem-perature and Humidity Drying Conditions):5.3.1 Conduct all drying tests in a ventilated temperatureand humidity-controlled chamber. Allow the tempera
28、ture andrelative humidity to stabilize within the chamber prior to use.If elevated temperature without consideration for humidity isdesired, a convection oven can be used.4,55.3.2 Condition the substrate material, the coating to betested, and the application device for a minimum of1hinthetemperature
29、/humidity-controlled chamber prior to casting thewet film.5.3.3 Make all measurements at a temperature and relativehumidity as agreed upon between contracting parties. Recordthe actual temperature and relative humidity employed fortesting. All dry time measurements are made with the coatedpanels in
30、a horizontal position while drying.5.3.4 Apply the wet film according to the coating manufac-turers instructions. In the absence of any specific materialspecification or product data sheets, instructions for casting thefilm should be agreed upon between contracting parties.5.3.5 Films to be tested s
31、hould have practical thicknessescommensurate with the coating manufacturers recommenda-tions.All testing should be performed within an area at least 15mm 12 in. from any film edge.5.3.6 Minimize opening and closing of the temperature andhumidity-controlled chamber to prevent fluctuation of condi-tio
32、ns.5.4 Method D (Shop/Field Procedure):5.4.1 Measure and record air and surface temperature, andrelative humidity immediately prior to coating application.5.4.2 Apply the wet film according to the coating manufac-turers instructions. In the absence of any specific materialspecification or product da
33、ta sheets, instructions for applyingthe film should be agreed upon between contracting parties.5.4.3 Apply the wet film to the same substrate and surfacetexture using the same application equipment and parametersas are intended to be used in the shop/filed during production.5.4.4 Films to be tested
34、should have practical thicknessescommensurate with the coating manufacturers recommenda-tions.6. Preparation of Test Specimens6.1 Carry out all tests as described in 6.1.1 6.1.5, unlessotherwise noted.6.1.1 All test specimens (test surfaces for Method D) shallbe prepared and tested by one operator p
35、roficient in themethods to be used. Apply the coating material to the agreedupon substrate in duplicate at a time arranged so that evaluationintervals will fall within the normal working hours of theoperator.6.1.2 If the coating to be tested requires an induction time,cast/apply the wet film after t
36、he induction period.6.1.3 For Methods A, B and C, apply the materials to betested on clean glass panels, smooth cold-rolled steel panels orother specific substrate of suitable dimensions agreed uponbetween contracting parties. Ground-glass plates are moresuitable for certain types of coatings that t
37、end to crawl, such aslow-viscosity drying oils. Suitable plates can be prepared by4Consider potential safety hazards associated with the flash point of any organicsolvents included in the paint/coating vehicle.5A hot plate may be used to generate different air and surface temperature, ifrequired.D16
38、40/D1640M 14 (2018)2roughening the surface of polished glass by grinding a paste ofsilicon carbide (grit 1F) and water between two glass plates.6.1.4 For Methods A, B and C cast the coating materials tothe substrate with a wet film applicator having a clearancesufficient to yield the recommended wet
39、 and resulting dry filmthickness. Other methods to produce a film of uniform thick-ness such as those described in Practices D823 may be used asagreed upon between contracting parties.6.1.5 Measure the wet film thickness in accordance withPractice D4414.7. Procedure7.1 When test methods or end point
40、s other than those listedin 7.2 7.8 are used, there shall be a prior agreement betweenthe contracting parties.7.2 Set-To-Touch TimeLightly touch the test film with thetip of a finger (clean and free of grease) and immediately placethe fingertip against a piece of clean, clear glass. Observe if anyof
41、 the coating is transferred to the glass. For the purpose of thistest, the pressure of the fingertip against the coating shall not begreater than that required to transfer a spot of the coating from3to5mm18 to316 in. in cross section. The film isset-to-touch when it still shows a tacky condition, bu
42、t none ofit adheres to the finger. Remove any coating from the fingertipimmediately. The use of a glove, finger cots or the presence offreshly-applied cosmetic products/hand creams may interferewith the test results.7.3 Dust-Free Times (Applicable to Methods A, B, and Conly):7.3.1 Cotton Fiber Test
43、MethodSeparate a number ofindividual fibers from a mass of absorbent cotton with the aidof tweezers. At regular drying intervals, drop several of thecotton fibers from a height of 25 mm 1 in. onto a markedsection of the film. The film is considered to have dried dustfree when the cotton fibers can b
44、e removed by blowing lightlyover the surface of the film.7.4 Tack-Free Times (Applicable to Method A only):7.4.1 Mechanical Test Method (Tack Tester6)The tacktester is comprised of a base or surface-contacting portion25-mm 1-in. square and a counter-balancing portion 25 by 50mm 1 by 2 in. in area. B
45、oth portions are made up from acontinuous metal strip 0.41 to 0.46 mm 0.016 to 0.018 in. inthickness. To prepare the apparatus for use (see 7.4.1.1), fit thebase with several thicknesses of masking tape and paper stripsto provide a means of attaching the aluminum foil and so adjustthe angle of the 1
46、 by 2-in. counter-balancing strip so that aweight of 5 g placed in the geometric center of the base portionis just sufficient to overcome the unbalanced force.7.4.1.1 The tester is prepared by following steps in se-quence:(1) Wrap the metal base with three thicknesses of maskingtape, sticky side out
47、,(2) Cover the outer layer with a good grade of paper, exceptfor two exposed strips, equally spaced, about 6.4 by 25 mm 14by 1 in. in area on the top of the tester, and(3) Cover the paper on the contact side of the base with onethickness of pressure-sensitive cellulose tape previously fixedto the me
48、tal base of the tester. The cellulose tape serves twopurposes: (1) to pull the layers of masking tape firmly againstthe front of the metal base, and (2) to provide a smooth surfacefor the foil.(4) Attach the aluminum foil to the base of the tester bypressing gently but firmly a 25 by 50-mm 1 by 2-in
49、. piece offoil, 13 m 0.0005 in. in thickness against one of the 6.4 by25-mm 14 by 1-in. exposed strips of masking tape on the topsurface of the base. Wrap the foil tightly and smoothly aroundthe base, exposing the shiny side, and finally press the outerend gently against the remaining exposed strip of maskingtape. When it finally becomes necessary to replace wrinkled orsoiled aluminum foil, the ends are easily removed from themasking tape by exerting a slow, even, upward pull sufficient toovercome the tack of the tape wi
