1、Designation: D685 12D685 17 An American National StandardTechnical Association of Pulp andPaper Industry Standard Method T 402Standard Practice forConditioning Paper and Paper Products for Testing1This standard is issued under the fixed designation D685; the number immediately following the designat
2、ion indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope Scope*1.1 This practice defines the s
3、tandard atmospheres for normal preconditioning, conditioning, and testing of paper and paperproducts, paperboard, fiberboard, and containers made from them. It also specifies procedures for handling these materials in orderthat they may reach equilibrium with the respective atmosphere.1.2 This pract
4、ice does not include special conditioning and testing atmospheres, such as those that attempt to simulate tropicalor arctic environments.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to
5、establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Developme
6、nt of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D585 Practice for Sampling and Accepting a Single Lot of Paper, Paperboard, Fiberboard, and Related Product (Withdraw
7、n2010)3D4332 Practice for Conditioning Containers, Packages, or Packaging Components for TestingE171/E171M Practice for Conditioning and Testing Flexible Barrier Packaging2.1 ISO Standards:2ISO 187 Paper, board and pulps - Standard atmosphere for conditioning and testing and procedure for monitoring
8、 theatmosphere and conditioning of samplesBoard and PulpsStandardAtmosphere for Conditioning and Testing and Procedurefor Monitoring the Atmosphere and Conditioning of Samples2.2 TAPPI Standard:3TAPPI T400 Sampling and Acceptance of a Single Lot of Paper, Paperboard, Containerboard or Related Produc
9、tTAPPITAPPI/ANSI T402 sp-03 Standard Conditioning and TestingAtmosphere for Paper, Board, Pulp Handsheets and RelatedProducts3. Significance and Use3.1 The preconditioning requirement is important because physical properties of a sample at 50 % relative humidity dependupon whether the sample is brou
10、ght to 50 % from a higher or lower relative humidity. A detailed discussion of the importance ofpreconditioning may be found in Annex A1.3.2 The conditioning and testing atmospheres are important because both temperature and relative humidity have significanteffects on the physical properties of pap
11、er and board. A more detailed discussion of the importance may be found in Annex A2.1 This practice is under the jurisdiction of ASTM Committee D10 on Packaging and is the direct responsibility of Subcommittee D10.21 on Shipping Containers andSystems - Application of Performance Test Methods.Current
12、 edition approved Nov. 1, 2012April 1, 2017. Published December 2012June 2017. Originally approved in 1942. Last previous edition approved in 20072012 asD685-93(2007)D685 12., which was withdrawn May 2010 and reinstated in November 2012. DOI: 10.1520/D0685-12. DOI: 10.1520/D0685-17.2 Available from
13、American National Standards Institute (ANSI), 25 W. 43rd St., W43rd St, 4th Floor, New York, NY New York 10036, http:/www.ansi.org.http:/www.ansi.org.3 Available from Technical Association of the Pulp and Paper Industry (TAPPI),(TAPPI) 15 Technology Parkway South, Norcross,Norcross GA 30092, http:/w
14、ww.tappi.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users cons
15、ult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,
16、 PA 19428-2959. United States13.3 This standard is technically identical to TAPPI T-402.4. Standard Atmospheres4.1 Preconditioning Atmosphere10 to 35 % relative humidity and 22 to 40C (see Annex A1 and Annex A2).4.2 Conditioning Atmosphere50.0 6 2.0 % relative humidity and 23.0 6 1.0C.4.3 Testing At
17、mosphereSame as 4.2.NOTE 1It is important to distinguish between the overall limits of the temperatures within which conditioning and testing may be carried out andthe limits within which the temperature must be maintained in order to maintain the specified relative humidity limits; that is, the clo
18、se temperaturetolerance of 61C required in Average values must fall within these limits. Momentary fluctuations 4.2and 4.3 will not in itself ensure the close relativehumidity requirement of 62 % relative humidity, as a sudden change of 1C when at 23C and 50 % relative humidity will change the relat
19、ive humidityabout 5 to 6 %. measurement limitations may cause individual measurements to vary up to +2C (+3.6F) and +5 % relative humidity without significantimpairment of test precision.5. Apparatus5.1 Preconditioning ChamberA room or cabinet in which sample sheets or specimens may be individually
20、exposed tocirculating air at the preconditioning relative humidity and temperature.NOTE 2For smaller sheets or specimens, the required preconditioning may be achieved easily with a simple cabinet, if no other means are available.If this cabinet is operated in a room maintained at 50 % relative humid
21、ity and 23C and so designed that room air is drawn through it, and if the airentering and in the cabinet is heated to a temperature of 39 6 1C, the relative humidity in the cabinet will be in the required range (that is, 20 6 3 %relative humidity). Commercially available forced-ventilation “ovens” s
22、hould prove satisfactory. Input air to the oven should be drawn from the standardroom, output should be vented outside of the standard room.5.1.1 For many papers and boards, approximately the same preconditioning moisture content obtained by the above proceduremay be achieved by using a sealed cabin
23、et operated in a room maintained at 23 6 1C and using a saturated solution of lithiumchloride (LiCl) to obtain a relative humidity of about 12 to 13 %.5.1.2 For larger rooms needed for preconditioning sealed containers and large sheets, the required low relative humidity maybe achieved by drawing ai
24、r over a refrigerator expansion coil operating at a few degrees above freezing temperature.5.2 Conditioning and Testing ChamberOne or more rooms or cabinets in which sample sheets or specimens may beindividually exposed to circulating air at the conditioning relative humidity and temperature, and th
25、en tested under the sameconditions.NOTE 3The required relative humidity (50.0 6 2.0 %) and temperature (23.0 6 1.0C) are difficult to achieve and therefore careful attention mustbe given to the design, evaluation, and maintenance of the “standard room.”5.3 HygrometerAny instrument that can indicate
26、directly or indirectly the relative humidity of the air with a calibratedaccuracy of 60.5 % relative humidity.5.4 ThermometerEither the dry bulb of a psychrometer (that is, a hygrometer of the wet- and dry-bulb type) or a separatethermometer of any convenient design. If a separate thermometer, it sh
27、ould be graduated to 0.2C or closer with scale errors notexceeding these values. (Psychrometer thermometers must be graduated and correct to 0.1C or closer and carefully matched toeach other to give the required accuracy and repeatability in the measurement of relative humidity.)6. Procedure6.1 Obta
28、in and preserve the sample in accordance with PracticeTAPPI D585.T400. In particular, avoid exposure of the sampleto direct sunlight, to extremes of temperature, and, to relative humidities above 58 % (see Annex A1). If the sample is to be heldfor some time before testing, preserve it at a temperatu
29、re below 25C and relative humidity below 58 %, but not below 10 % asthe paper may curl or cockle and change in other respects.NOTE 4It has been reported that low-temperature storage below 10C slows aging effects. Samples should be protected against condensation.6.2 Cut the specimens from a sample wh
30、ere critical dimensions are involved only after conditioning the sample. Where thereare no critical dimensions, the specimens may be cut before preconditioning or conditioning.6.3 If shipping containers are to be sealed with aqueous adhesives, make the seal prior to preconditioning.6.4 Expose the sa
31、mple sheets or specimens to the preconditioning atmosphere so that both surfaces of single sheets and exteriorsurfaces of laminated products or sealed containers are freely exposed. This is best achieved by suspending them from overheador supporting them on a wire grid or rack.6.5 Precondition the s
32、ample sheets or specimens by exposing them as specified in 6.4 to the preconditioning atmosphere.Precondition for a minimum of 24 h, unless a lesser time has been found to give satisfactory results.NOTE 5For preconditioning apparatus of ample capacity and air circulation, the following preconditioni
33、ng times have usually been found satisfactory:single sheets of paper, less than 1 h; liners corrugating medium, chip board, box board, 1 to 2 h; corrugated and solid fiber board in sheet form, 5 to 10h; sealed boxes and shipping containers, 12 to 16 h; specially treated water vapor resistant papers
34、and boards, 24 h and more.D685 172NOTE 6If the sample is to be stored for some time after preconditioning, store at a temperature below 25C and a relative humidity below 40 % butnot below 10 %.6.6 Condition the sample sheets or specimens by exposing them as specified in 6.4 to the standard condition
35、ing atmosphere fora sufficient time for them to come into equilibrium with the atmosphere. Determine that equilibrium has been obtained by weighingthe sheets or specimens at time intervals which increase roughly geometrically. Plot the weight against log time (that is, onsemilogarithmic paper); the
36、desired equilibrium exists when the plotted curve becomes essentially parallel to the time axis.NOTE 7With good air circulation and ample capacity, a conditioning period of 4 h is usually sufficient for paper of ordinary weight and composition.A minimum time of exposure of 5 to 8 h will be required
37、for boards, and unsealed boxes, with a minimum time of 16 h or more for sealed fiberboardboxes, and much longer periods for boards of heavy substances and specially treated water-vapor resistant papers (for example, a minimum of 72 h forwax treated containers).6.7 Handle the preconditioned and condi
38、tioned sheets or specimens as little as possible; especially avoid touching or breathingon test areas.6.8 Test the specimens in the standard testing atmosphere.7. Report7.1 The report shall include the following:7.1.1 Temperature, relative humidity, and total time of:7.1.1.1 Preconditioning,7.1.1.2
39、Conditioning before testing,7.1.2 Minimum and maximum temperature and relative humidity during testing, and7.1.3 Any variations in procedure from this practice.8. Precision and Bias8.1 No statement is made about either the precision or the bias of the practice since it merely states the environmenta
40、l conditionsunder which paper tests are to be carried out. They could affect the precision and bias of the test methods, but such effects arereflected in the precision and bias statement appearing in the individual test method.9. Keywords9.1 conditioning; paper; paper products; reconditioning; stand
41、ard atmosphereANNEXES(Mandatory Information)A1. IMPORTANCE OF PRECONDITIONINGA1.1 The physical properties of a sample at 50 % relative humidity depend on whether the sample was brought to 50 % fromhigher or lower relative humidities. This “humidity hysteresis effect” is 5 to 25 % of the test value f
42、or many physical properties.For example, a hysteresis effect of 1.5 % moisture content (or 25 % of the test value of 6 % moisture content) is typical.Preconditioning on the dry side within the range specified will avoid most of the hysteresis effect and result in the moisture contentof a given sampl
43、e being established within 0.15 % when the sample is later conditioned to 50 % relative humidity and 23 C.Conditioning downto 50 % gives most papers a moisture content very nearly the same as conditioningupto 60 %.A1.2 For the sake of obtaining close interlaboratory agreement, especially on physical
44、 properties, a specified preconditioningprocedure is necessary but not always sufficient. While preconditioning practically eliminates the hysteresis effect, it has littleinfluence on strain relaxation effects. The latter depend on the entire previous moisture history of the sample, especially on th
45、econditions of initial drying and tension, and on the duration and degrees of subsequent excursions to high humidities (that is, aboveabout 58 % relative humidity). Consequently, for very close interlaboratory agreement a standardized procedure for handling thesample from manufacture to testing is r
46、equired.A1.3 For mill control and similar intra-laboratory purposes, the preconditioning step may often be eliminated. For some propertiesand materials, preconditioning may not be necessary, either because of the smallness of the humidity hysteresis effect or becauseof lower test accuracy requiremen
47、ts.D685 173A2. IMPORTANCE OF TEMPERATUREA2.1 A tolerance of 1.0C has been adopted in a number of countries. It is recommended along with 62 % relative humidity bythe technical committee, ISO/TC 125 on Enclosures and Conditions forTesting, whenever close tolerances are required, as in paperand board
48、testing. Both temperature and relative humidity have significant effects on the physical properties of paper and board.For some properties of paper and board (for example, MD tensile and CD stretch) a change of 1C may have nearly as much effectas a change of 2 % relative humidity. For synthetic fibe
49、rs and plastic laminates the temperature effect may be greater than therelative humidity effect.SUMMARY OF CHANGESCommittee D10 has identified the location of selected changes to this standard since the last issue (D685 12)that may impact the use of this standard. (Approved April 1, 2017.)(1) Removed previous Subsection 2.1 and renumbered subsequent subsections accordingly.(2) Revised Subsections 2.1 and 2.2.(3) Added new Subsection 3.3.(4) Revised Note 1.(5) Revised 6.1.ASTM International takes no position respecting the validity of any pate
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