1、Designation: F392/F392M 11 (Reapproved 2015)Standard Practice forConditioning Flexible Barrier Materials for Flex Durability1This standard is issued under the fixed designation F392/F392M; the number immediately following the designation indicates the yearof original adoption or, in the case of revi
2、sion, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers conditioning of flexible barriermaterials for the determination of flex resista
3、nce. Subsequenttesting can be performed to determine the effects of flexing onmaterial properties. These tests are beyond the scope of thispractice.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
4、equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues 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 us
5、er 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:2E171 Practice for Conditioning and Testing Flexible BarrierPackagingF2097 Guide for Design and Evaluation of Pr
6、imary FlexiblePackaging for Medical Products3. Terminology3.1 pinhole, na small opening of non-specific shape ordimension that passes completely through all layers of aflexible material.3.1.1 DiscussionThe use of the term “pin” provides therelative size reference as in a small hole made with or as i
7、f witha pin.4. Summary of Practice4.1 Specimens of flexible materials are flexed at standardatmospheric conditions defined in Specification E171, unlessotherwise specified. Flexing conditions and number and sever-ity of flexing strokes vary with the type of structure beingtested. The flexing action
8、consists of a twisting motionfollowed, in most cases, by a horizontal motion, thus, repeat-edly twisting and crushing the film. The frequency is at a rateof 45 cycles per minute (cpm.)4.2 Flex failure is determined by measuring the effect of theflex conditioning on the barrier and/or mechanical perf
9、ormanceof the structure. The property to be evaluated determines theappropriate conditioning level.4.3 The various flex conditioning levels are summarized asfollows:4.3.1 Condition AFull flex for 1 h (that is, 2700 cycles).4.3.2 Condition BFull flex for 20 min (that is, 900 cycles).4.3.3 Condition C
10、Full flex for 6 min (that is, 270 cycles).4.3.4 Condition DFull flex for 20 cycles.4.3.5 Condition EPartial flex only for 20 cycles.5. Significance and Use5.1 This practice is valuable in determining the resistance offlexible-packaging materials to flex-formed pinhole failures.Conditioning levels A,
11、 B, or C are typically used for thisevaluation.5.2 This practice is valuable for determining the effect offlexing on barrier properties such as gas and/or moisturetransmission rates. Conditioning levels D or E are typicallyused for this evaluation.5.3 This practice does not measure any abrasion comp
12、onentrelating to flex failure.5.4 Failures in the integrity of one or more of the plies of amulti-ply structure may require different testing than thedetection of holes completely through the structure. Perme-ation tests using gas or water vapor can be used in conjunctionwith the flex test to measur
13、e the loss of ply integrity. However,any permeation test requiring a pressure differential will notmeasure the permeation coefficient in the presence of pinholes.For a list of test methods refer to Guide F2097.5.4.1 The various conditions described in this procedure areto prevent testing a structure
14、 under conditions that either give1This practice is under the jurisdiction of ASTM Committee F02 on FlexibleBarrier Packaging and is the direct responsibility of Subcommittee F02.50 onPackage Design and Development.Current edition approved Oct. 1, 2015. Published October 2015. Originallyapproved in
15、1974. Last previous edition approved in 2011 as F392/F392M -11. DOI:10.1520F0392_F0392M-11R15.2For referenced ASTM standards, 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
16、 Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1too many holes to effectively count (normally greater than 50),or too few to be significant (normally less than five persample). Material structure, purp
17、ose for testing and a mutualagreement between parties involved are important points toconsider in the selection of conditioning level for testing.6. Apparatus6.1 Flex Tester,3designed so that it can be set up inaccordance with the specifications listed in Section 9. Thisapparatus shall consist essen
18、tially of a 90 6 1-mm 3.5-in.diameter stationary mandrel and a 90 6 1 mm diametermovable mandrel spaced at a distance of 180 6 2 mm 7 in.apart from face-to-face at the starting position (that is, maxi-mum distance) of the stroke. Mandrels shall contain vents toprevent pressurization of samples. The
19、specimen supportingshoulders on the mandrels shall be 13 6 1 mm 0.5 in. wide.The motion of the movable mandrel is controlled by a groovedshaft to which it is attached. For the full or maximum stroke thegroove is designed to give a twisting motion of 440 6 4 in thefirst 90 mm of the stroke of the mov
20、able mandrel, followed bya straight horizontal motion of 65 mm 2.5 in., so that at theclosed position the mandrels are 25 6 1 mm 1 in. apart. Themotion of the machine is reciprocal with a full cycle consistingof the forward and return strokes. The machine operates at 456 2 cpm.6.1.1 Fig. 1 shows the
21、 planar evolution of the helical groovein the driven shaft to give the required 440 (37 helix angle)twisting motion and the straight horizontal motion.6.1.2 For the partial flex used with Condition E the movablehead is set to travel only 80 mm 3.25 in. of the 180-mm7-in. spacing. Therefore, only app
22、roximately 90 % of thetwisting stroke is utilized giving a twisting motion of only400, and none of the horizontal stroke is utilized.6.2 Tape, flexible, double-sided, pressure-sensitive, notmore than 13 mm 0.5 in. wide.6.3 Template, for cutting 200 by 280 6 2-mm 8 by 11-in.samples.7. Test SpecimensA
23、ll Conditions7.1 Cut the samples into 200 by 280-mm 8 by 11-in. flatsheets with the 200-mm dimension in the direction to be tested.This will also be in the direction of the flex-tester axis.7.2 Flex condition four or more specimens in their machinedirection and an additional four or more in their tr
24、ansversedirection. In addition, collect an equal number of controlspecimens from adjacent locations to undergo the same testsfor pinholes and/or barrier properties.3The Gelbo Tester, which is capable of producing the prescribed flexing action,available from the United States Testing Co., Inc., 1415
25、Park Ave., Hoboken,NJ 07030, or its equivalent, has been found satisfactory for this practice.FIG. 1 Planar Evolution of Gelbo Shaft Helical Groove 30.70-mm 1.20-in. Diameter Shaft)F392/F392M 11 (2015)27.3 Do not seal or tape the short edges of the specimen (notin contact with the mandrels), but lea
26、ve them open. Usedouble-sided pressure-sensitive tape, not more than 13 mm (0.5in.) wide, to attach the long edges of the unsealed specimen inthe shape of a cylinder to the flex-tester mandrels.8. Environmental Conditioning8.1 If appropriate, condition the specimens for at least 24 hat 50 6 5 % rela
27、tive humidity and 23 6 2C, unless otherwisespecified in agreements.9. Procedure9.1 Flexing:9.1.1 Atmospheric ConditionsIf required, conduct flexingat the standard atmospheric conditions of 23 6 2C and 50 65 % relative humidity, unless otherwise specified.9.1.2 Flex Tester SetupSetup the flex tester
28、for maximumthrow and twisting action. This setup gives a twisting motionof 440 in the first 90 mm 3.5 in. of stroke, and is followedby a straight horizontal motion of 65 mm 2.5 in. at 45 cpm.With this setup, space the face of the moving mandrel at adistance of 180 mm 7 in. from the face of the stati
29、onarymandrel when the moving mandrel is at its starting position. Inthe closest position the moving mandrel is 25 mm 1 in. fromthe stationary mandrel. Attach the long edges of the flexiblebarrier specimen to the flex-tester mandrels, which have beenlined with double-sided pressure-sensitive tape. Ho
30、se clampsmay also be used to supplement the double-sided tape to securethe specimen to the mandrels.9.1.3 Condition ATurn the flex tester on, and allow thespecimen to flex for1hat45cpm(that is, 2700 cycles).9.1.4 Condition BTest conditions are the same as Condi-tion A, except that the flex period is
31、 20 min at 45 cpm (that is,900 cycles at full flex and twisting action).9.1.5 Condition CTest conditions are the same as Condi-tion A, except that the flex period is 6 min at 45 cpm (that is,270 cycles at full flex and twisting action).9.1.6 Condition DTest conditions are the same as Condi-tion A, e
32、xcept that the flex period is 20 cycles at 45 cpm (thatis, 20 cycles at full flex and twisting action).9.1.7 Condition ESet up the flex tester for the partial flexdescribed in 9.1.2 with the following exception: the movablehead is set to travel only 80 mm 3.25 in. of the 180-mm7-in. spacing (the dis
33、tance between the mandrels at theirmaximum separation or starting position). Therefore, onlyabout 90 % of the twisting stroke giving a twisting motion ofonly 400 is utilized and none of the horizontal stroke isutilized. When the mandrels are at their closest position theywill be 95 mm 3.75 in. apart
34、. The partial flex period underthis “short stroke” setup will be 20 cycles at 45 cpm.9.2 Determination of Results:9.2.1 Remove the flexible barrier specimen from the flextester and mark the 150 by 200-mm 6 by 8-in. center location.Samples for flex durability testing, for either pinholes or plyintegr
35、ity, should be taken from this region.9.2.2 Perform the test method to be used to measure theproperty required after conditioning for flex. Proceed withtesting material sample as directed by test method standard.10. Report10.1 The report shall include the following:10.1.1 Flex Conditioning level, in
36、cluding the number ofcycles and whether full or partial flex was used.10.1.2 Identification of the test method(s) used to determinepresence of pinholes or effect on barrier properties. Report dataas individual and average pinhole count per 300 cm248 in.2in machine direction and in transverse directi
37、on or with otherunits as appropriate for test method used.10.1.3 Report data on unflexed control in appropriate unitsfor method used to test.10.1.4 Sample conditioning and test conditions used, andwhere applicable, sample thickness and structure.10.1.5 Report any unusual failures such as tears.10.1.
38、6 Description of deviations from the indicated practice.11. Keywords11.1 barrier; barrier materials; flex crack; flex resistance;flexible; gas permeation; gas transmission rate; pinhole ; watervapor transmission rate; WVTRASTM International takes no position respecting the validity of any patent rig
39、hts 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 to revision at any
40、 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. Your comments wi
41、ll 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 copyrighted by AS
42、TM 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). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 11 (2015)3
