1、Designation: F 1445 00 (Reapproved 2004)Standard Test Method forDetermining Static Thermal Sensitivity of Direct ThermalMedia1This standard is issued under the fixed designation F 1445; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, 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.1. Scope1.1 This test method covers the static thermal response ofdirect thermal media (paper, film, and paper/fil
3、m laminates) todetermine temperatures required for activation, functional andsaturated densities. Static thermal response is a key test fordetermining heat stability characteristics of direct thermalmedia.1.2 The instrument described in this test method may beused to develop product specifications,
4、specification accep-tance, product development, or research applications.1.3 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are for informa-tion only.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with
5、 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 ANSI Standard:IT 2.17-1995 Density Measurements Geometric Condi-tions for Reflection
6、 Density23. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 functional temperaturetemperature which generatesan optical density of 1.00.3.1.2 static thermal responsethe generation of the thermalresponse of a thermal media within a given printing systemover a specific range of tem
7、perature levels.4. Summary of Test Method4.1 This test method is intended to determine the staticthermal response of direct thermal media. The temperatureversus density curve obtained is a characterization of a givencoating and media substrate. Curves can be used to determineuniformity within and be
8、tween direct thermal media lots. Thetest equipment and test procedures are not intended to simulatethermal response under actual end-use conditions in a directthermal printer. Although no specific manufacturers have beenidentified for this equipment, any temperature controller, tem-perature sensor,
9、and test fixture with equivalent signal outputcapabilities would be suitable.4.2 To determine the static thermal response of directthermal media, a sample is inserted into the test fixture with thecoated surface up towards the heated platens. When fullyinserted, a switch is tripped clamping the test
10、 media in contactwith the heated platens under a given pressure for a prescribedlength of time set with a timing mechanism.4.3 The temperature controllers allow the heated platens tobe adjusted to specific surface temperatures.4.4 The thermal response or density saturation curve can beobtained by ex
11、posing samples from given direct thermal mediato various temperatures for a specified time period.5. Significance and Use5.1 This test method enables static thermal response com-parisons between direct thermal media and facilitates processcontrol.5.2 Comparisons can be made between and within therma
12、lmedia production lots from the same manufacturer.5.3 Comparisons can be made between thermal mediaproduct grades from different manufacturers.5.4 This test method is useful in predicting heat stability forend-use applications.6. Interferences6.1 Wide variations in environmental conditions (especial
13、lyrelative humidity) will affect the resulting image density withthis test method.6.2 The length of elapsed time between sample exposure tothe heated plate and density readings may affect actual read-ings. For best results, density readings should be made within30 min of imaging.1This test method is
14、 under the jurisdiction ofASTM Committee F05 on BusinessImaging Products and is the direct responsibility of Subcommittee F05.06 onCarbonless Copy Paper.Current edition approved Dec. 1, 2004. Published December 2004. Originallyapproved in 1992. Last previous edition approved in 2000 as F 1445 00.2Av
15、ailable from American National Standards Institute, 25 W. 43rd St., 4thFloor, New York, NY 10036.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.3 Since direct thermal media are sensitive to light expo-sure, samples should be cover
16、ed or otherwise protected fromlight between tests. Excessive exposure to light can affect finaltest results.6.4 Variations in the length of time direct thermal mediacontact the heated platens will affect the resulting imagedensity.6.5 Very large differences in the basis weight of directthermal media
17、 samples and coating thickness may have asignificant affect on the results obtained.6.6 This test method is not useful for predicting perfor-mance in direct thermal printers.7. Apparatus and Materials7.1 Custom Built Thermal Response Fixture (see Fig. 1).7.2 DescriptionThe test unit has a 2-in. diam
18、eter pistonand a 48-in.2(309.7 cm2) footprint (12 heated blocks at 1 by 4in. (2.54 cm by 10.16 cm). At 40 psig, the gage pressurecalculates out to 2.62 lb/in.2(0.18 kg/cm2). The pressure is notcritical. Repeatable results can be achieved in the range from1.8 to 2.6 lb/in.2(0.12 to 0.18 kg/cm2). The
19、surface beneath theheated platen consists of a14-in. (0.64 cm) thick siliconizedrubber pad on a flat steel surface. Temperature controllers areOmega 4001AJF-T Digital Temperature Controller, or equiva-lent.7.3 Simpson Electric Company Temperature Adapter, (50to +150C) with Simpson 467 Digital Displa
20、y Multimeter, orequivalent equipment.7.4 Reflection Densitometer, with aperture smaller than theimage area to be measured and meeting the requirements ofANSI IT 2.17-1995, operating in visual density mode.8. Test Specimen8.1 The test specimen shall be from sheets or roll samples ofdirect thermal med
21、ia that has not been adulterated since it wasmanufactured.8.2 Cut samples into individual strips 5 by 18 in. (127 by457.2 mm) if the test instrument described in this test methodis used, or cut to a size that will fit the test instrument used.9. Calibration9.1 Calibrate the electronic thermal sensor
22、 head at theinterval prescribed by the equipment manufacturer. Use atemperature pyrometer like the Simpson Electric unit describedin 7.3 to perform calibrations. Measure temperature to within61C.9.2 Calibrate the densitometer in accordance with the manu-facturers instructions.10. Conditioning10.1 Al
23、though no special conditioning of thermal mediasamples is required, it would be prudent to compare only testsrun under the same environmental and aging conditions.10.2 Under ideal conditions, the test instrument should beoperated in a conditioned room.11. Procedure11.1 Switch the test instrument on
24、and set temperaturecontrollers to desired settings. Recommended temperaturesettings would start at 65C and increase in 4 increments to109C. To obtain above or below the recommended range, thetemperature controllers can be reset and additional tests con-ducted. Additional temperature settings will in
25、crease the testaccuracy in the critical region or where a small increase intemperature results in a significant increase in image density.11.2 Set the timer device on the unit for 5-s dwell.11.3 Set the platen pressure for 40 psig or 2.6 lb/in2(0.18kg/cm2).11.4 Insert the test sample horizontally in
26、to the test areawith the thermal coated side up. A micro switch will sense thesample presence and initiate the test.11.5 Remove the sample from the test instrument andmeasure the image density.11.6 Record three density readings for each temperature andrecord the average value. Plot the average of th
27、e three on graphpaper with temperature (C) on the x-axis and density on they-axis (see Fig. 2).12. Report12.1 Report the following information:12.1.1 Sample Identification:12.1.1.1 Coated roll batch or lot number,12.1.1.2 Manufacture and product code,12.1.1.3 Date or time, or both,12.1.1.4 Test cond
28、itions, dwell time and platen pressure,and12.1.1.5 Ambient temperature and relative humidity.12.1.2 Report the density data obtained in tabular form or ascurves such as those shown in Fig. 2.12.1.3 The density versus temperature curves generated bythe test samples may be compared for the rate at whi
29、ch theyreach saturation (maximum darkness), the maximum densityobtained and the temperature at which the density starts todecrease.13. Precision and Bias13.1 Repeatable measurements on the same media and sametest equipment should agree within 66 % of the averageoptical density. This precision and bi
30、as statement is based onthe equipment listed in Section 7.13.2 Measurements between laboratories may not be repro-ducible because of differences in samples, test equipment,FIG. 1 Thermal Response FixtureF 1445 00 (2004)2temperature/relative humidity, and testers. A laboratory corre-lation test may b
31、e used to minimize differences between testequipment and establish agreement between laboratories.14. Keywords14.1 direct thermal media (paper, film, and paper/film lami-nate); static thermal response; static thermal response curveASTM International takes no position respecting the validity of any p
32、atent 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 to revisi
33、on 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. Your co
34、mments 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 copyrigh
35、ted 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 serviceastm.org (e-mail); or through the ASTM website(www.astm.org).FIG. 2 Static Thermal Response CurveF 1445 00 (2004)3