1、Designation: D 4497 94 (Reapproved 2004)e1Standard Test Method forDetermining the Open Time of Hot Melt Adhesives (ManualMethod)1This standard is issued under the fixed designation D 4497; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revi
2、sion, the year 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.e1NOTEAn editorial change was made in 3.1 in September 2004.1. Scope1.1 This test method covers the manual dete
3、rmination of theopen-time range of hot-melt adhesives under the stated condi-tions.1.2 The values stated in SI units are to be regarded as thestandard. The inch-pound units in parentheses are provided forinformation only.1.3 This standard does not purport to address all of thesafety concerns, if any
4、, 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. Referenced Documents2.1 ASTM Standards:2D 907 Terminology of AdhesivesE 171 Specification f
5、or Standard Atmospheres for Condi-tioning and Testing Flexible Barrier MaterialsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 DefinitionsMany of the terms found in this testmethod are defined in Terminology D 907.3.2 Definitions of
6、 Terms Specific to This Standard:3.2.1 open time, nthe time available between applicationof the adhesive to the first substrate and the mating of thesecond substrate which still results in a minimum of 50 % fibertear when tested at ambient conditions.4. Summary of Test Method4.1 In this test method,
7、 open time is determined by bondingtogether with the adhesive, pieces of standard paper at intervalsof 5 s sequentially after the molten adhesive has been appliedusing a heated film applicator on one surface. The bondedspecimens are examined later to determine the longest timeperiod, between applica
8、tion of the adhesive to one surface andmating with a second surface, which allows substantial bond-ing.5. Significance and Use5.1 This test method allows comparing the open time ofseveral hot melt adhesives.5.2 This test method is not intended to provide the open-time observed for a specific adhesiv
9、e in a specific manufactur-ing operation. This test method can be used to compare theperformance of adhesives which are represented to be identicalor to rank the open-time of a group of hot melt adhesives.6. Apparatus6.1 Oven, which meets the precision required by the proce-dure, should be used to h
10、eat the adhesive sample and theapplicator.6.2 Film ApplicatorMultiple clearance 0.125 to 1.25 mm(5 to 50 mil) square P.G. and T. Number 2 Film Applicator3capable of providing an applied film of adhesive having anominal width of 50 mm (2 in.).6.3 Hand Thermometer, preferably metal, capable of mea-sur
11、ing the temperature of the hot-melt with an accuracy of61C (62F).6.4 Primary Standard Substrate, 200 by 280 mm (8 by 11in.), NBS Standard Reference Material 1810 (Liner Board).4Substrates are to be conditioned as described in SpecificationE 171.6.5 Secondary Standard Substrate, 125 mm (5 in.) length
12、 inthe material direction cut to 19 mm (0.75 in.) wide, NBSStandard Reference Material 1810 (Liner Board).36.6 Glass Beakers (600 mL), for melting the adhesive.6.7 Watchglass, to cover beaker.1This test method is under the jurisdiction of ASTM Committee D14 onAdhesives and is the direct responsibili
13、ty of Subcommittee D14.50 on Hot Melts,Pressure Sensitives, and Archival Adhesives.Current edition approved Sept. 1, 2004. Published September 2004. Originallyapproved in 1985. Last previous edition approved in 1999 as D 4497 94 (1999).2For referenced ASTM standards, visit the ASTM website, www.astm
14、.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.3Film Applicator No. 2 is available from Precision Gage and Tool Company, 28Volkenand Street, Dayton, OH 45410.4Available fro
15、m National Institute of Standards and Technology (NIST), 100Bureau Dr., Stop 3460, Gaithersburg, MD 20899-3460.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.8 Beakers, Tongs, and Protective gloves, for handling hotvessels and app
16、licators.6.9 Transparent Pressure Sensitive Tape.6.10 Stop Watch or Other Timer, graduated to at least 0.5 s.6.11 Weighted Rectangular Block, having at least onesmooth and flat wood face, 50 by 12.5 mm (2 by 0.5 in.)weighing 100 g (3.5 oz), the mass being uniformly distributed.6.12 Micrometer or Thi
17、ckness Gage, capable of measuringto the nearest 0.025 mm (1 mil).7. Sampling7.1 The test sample should be representative of the adhesivebeing tested.8. Procedure8.1 Add 300 6 10 g of the adhesive to the 600-mL glassbeaker and cover with a watch glass. Place the beakercontaining the adhesive into the
18、 oven and heat until at theapplication temperature recommended by the manufacturer.8.2 Concurrently heat the film applicator in the same ovento condition it to the sample temperature as in 8.1.8.3 Perform testing in a relatively draft-free room. While thesample is melting, prepare the substrates for
19、 testing as shownin Figs. 1 and 2.8.3.1 Tape the long sides of a piece of primary standardsubstrate (see 6.4), minimum sheet size 100 by 280 mm (4 by11 in.), to a flat smooth surface of low thermal conductivity,specifically to a larger piece of chipboard (such as from theback of a tablet). Then tape
20、 the chipboard to an underlyingsurface.8.3.2 Place the strips of the secondary standard substrate(see 6.5) across the width of the primary substrate, as shown inFig. 1, leaving approximately 6 mm (14 in.) between the strips.The top strip should be approximately 75 mm (3 in.) below thetop edge of the
21、 primary substrate. Using pressure sensitivetape, attach one end of the strips to the primary substrate. Foldthe unattached end of each strip back over the attached end sothat the primary substrate is exposed for application of theadhesive (see Fig. 2).8.4 Remove the sample from the oven, and by sti
22、rring withthe metal thermometer, quickly verify that the temperature iswithin 63C (65F) of the manufacturers recommendedapplication temperature.8.5 Quickly remove the adhesive applicator from the oven,and center it above the top strip of the secondary substrate. The0.5 mm (20 mil) gap should face do
23、wn and be near the top endof the primary substrate.8.6 Fill the applicator reservoir to approximately a14-in.level with conditioned hot adhesive.8.7 Move the applicator and the contained molten adhesivewith one smooth motion over the length of the paper takingapproximately2stocomplete the drawdown.N
24、OTE 1Approximately2sissatisfactory. The purpose is to standard-ize on a reasonable rate and eliminate an excessively fast or slowdrawdown which will affect the results.NOTE 2Trial applications should be made to determine the properapplicator gap to lay down a specified film thickness. Normally, a ga
25、p of0.50 mm (20 mil) will lay down a film of 0.25 mm (10 mil). Variations inapplied film thickness will occur because of differences in the hot flowproperties of the adhesive.8.8 Immediately after the film has been drawn down, startthe timer.8.9 At5sonthetimer, or a longer time if it is known thatan
26、 adhesive will have an open time longer than about 30 s, laythe top piece of secondary substrate across the cooling film,and continue sequentially at 5 s intervals. Use the weightedblock to apply immediately a momentary load of 5 s durationto press the strips onto the adhesive, moving the block tosu
27、ccessive strips as they are laid onto the adhesive. See Fig. 3.The wood face of the block faces the substrate. Repeat thisoperation until it is obvious the adhesive film has solidified andwill not bond to the secondary substrate.8.10 Allow the adhesive film to cool at ambient temperaturefor 30 to 60
28、 min before measuring.8.11 Measure the combined thickness of the adhesive filmand the two substrates. Subtract the thickness of the twosubstrates to determine the nominal adhesive thickness to thenearest 0.025 mm (1 mil).8.12 With a uniform motion, peel off each strip of secondarysubstrate at an ang
29、le of 90 to the surface. Take about 10 s topeel off each strip. If the paper tears near the initial edge, repeatthe peel from the opposite end of the strip. Record the percentarea of fiber tear for each strip and the time in seconds at whichthat strip was laid onto the cooling adhesive.FIG. 1 Second
30、ary Substrate Strips on Primary Substrate BeforeHot Melt ApplicationFIG. 2 Strips Drawn Back to Allow Hot Melt ApplicationD 4497 94 (2004)e128.13 Repeat the entire test procedure in 8.1-8.12 for a totalof three determinations.9. Report9.1 Report the mean open-time of the three replicate deter-minati
31、ons as the longest time, to the nearest 5 s, at which aminimum of 50 % fiber tear is obtained.9.2 Report the ambient temperature and relative humidity.9.3 Report nominal adhesive thickness, to the nearest 0.025mm (1 mil), as the mean of the three replicate determinations.9.4 Report the application t
32、emperature used (see 8.4).10. Precision and Bias10.1 The precision and bias of this test method is basedupon the testing of five typical hot melt adhesives by sixlaboratories. Statistical analysis of these data is tabulated inAppendix X1.10.2 The within-laboratory, single operator standard devia-tio
33、n of this test method for determining the open-time of a hotmelt adhesive is equal to or less than 2.6 s. This wasdetermined for typical hot melt adhesives having mean open-times by this test method of 20.8 s or less. The between-laboratory standard deviation including within- and between-laboratory
34、 variability is equal to or less than 8.4 s.11. Keywords11.1 application temperature; open timeAPPENDIX(Nonmandatory Information)X1. STATISTICAL ANALYSIS FOR TEST METHOD D 4497FIG. 3 Strips Successively Placed onto Hot MeltTABLE X1.1 Hot Melt Adhesive Open TimeBasic DataALaboratoryAdhesive TypePolyp
35、ropylene PolyamideEthylene-VinylPolyester PolyethyleneAcetate(1) (2) (3) (1) (2) (3) (1) (2) (3) (1) (2) (3) (1) (2) (3)1. Open Time,s 5 10 5 5 5 5 20 20 15 30 30 35 10 10 15Temperature, F 350 350 350 425 425 425 350 350 350 350 350 350 425 425 425Film Thickness, mil 10 10 10 12 12 12 10 10 10 12 11
36、 9 11 11 112. Open Time, s 5 5 5 40B40B40B15 15 15 20 20 20 20 20 20Temperature, F 349 348 352 420 422 425 352 351 352 321 326 324 420 421 420Film Thickness, mil 11 11.5 11 11 12 12.5 10 10.5 10 12.5 11 11 10 10 103. Open Time, s 10 10 10 5 5 5 20 20 20 30 30 30 20 20 25Temperature, F 350 350 350 42
37、5 425 425 350 350 350 325 325 325 425 425 425Film Thickness, mil 8 9 9 9 9 9 9 9 89999994. Open time, s 10 10 10 10 15 10 15 15 15 20 15 15 15 20 20Temperature, F 350 350 350 425 425 425 350 350 350 325 325 325 425 425 425Film Thickness, mil 10 10 10 1112 12 1112 910 10 1011 1011 1011 1011 1011 1011
38、 10115. Open Time, s 10 10 10 5 10 5 15 15 10 10 10 15 20 25 20Temperature, F 350 350 350 425 425 425 350 350 350 350 350 350 425 425 425Film Thickness, mil 6 5 7 8 8 9 4 3 53558876. Open Time, s 5 5 5 5 5 5 15 15 15 15 15 15 10 15 10Temperature, F 350 350 350 425 425 425 350 350 350 350 350 350 425
39、 425 425Film Thickness, mil 9 9 8 12 12 13 8 9 9 10 9 10 9 9 10AValues reported as 5 s are entered into the statistical analysis as 0.BOutlier values were eliminated from statistical analysis according to Practice E 691.D 4497 94 (2004)e13ASTM International takes no position respecting the validity
40、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 standard is subject t
41、o 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 International Headquarters.
42、 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 below.This standard is
43、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 serviceast
44、m.org (e-mail); or through the ASTM website(www.astm.org).TABLE X1.2 95 % Repeatability and Reproducibility IntervalsAdhesive Type95 % RepeatabilityIntervals WithinLaboratory, s95 % ReproducibilityIntervals BetweenLaboratories, sEthylene-Vinyl Acetate 3.3 7.6Polyester 7.5 12.7Polyethylene 4.7 8.2Pol
45、ypropylene 5.8 23.8Polyamide 7.5 14.7TABLE X1.3 95 % Confidence IntervalsAdhesive Type sEthylene-Vinyl Acetate 63.1Polyester 66.8Polyethylene 64.4Polypropylene 65.3Polyamide 66.9TABLE X1.4 Precision Estimates of Open Time of Hot MeltAdhesivesAdhesive TypeMean OpenTime,sSrSLVr,%VL,%SREthylene-Vinyl A
46、cetate 7.8 1.2 2.4 15 31 2.7Polyester 4.7 2.6 3.7 56 78 4.5Polyethylene 16.1 1.7 2.3 10 14 2.9Polypropylene 20.8 2.0 8.1 10 39 8.4Polyamide 17.5 2.6 4.4 15 25 5.2Average . . . 21 38 .where:Sr= estimated repeatability standard deviation within-laboratories for thatadhesive,SL= estimated between-labor
47、atory standard deviation for that adhesive,Vr= estimated standard deviation within-laboratories as a percent of themean open time,VL= estimated between-laboratories standard deviation as a percent of themean open time, andSR= between-laboratory estimate of standard deviation including within-and between-laboratory variability.D 4497 94 (2004)e14
