1、Designation: D7271 06 (Reapproved 2012)Standard Test Method forViscoelastic Properties of Paste Ink Vehicle Using anOscillatory Rheometer1This standard is issued under the fixed designation D7271; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、 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. Scope1.1 This test method covers the procedure for determiningthe viscoelastic properties of printing
3、 ink vehicles by measur-ing the G, G”, and tan delta using a controlled strain cone andplate oscillatory rheometer.1.2 This test method provides the flexibility of using severaldifferent types of rheometers to determine viscoelastic proper-ties in ink vehicles.1.3 This test method is not intended fo
4、r systems that arevolatile at procedure temperatures as evaporation may occureffectively changing the percent solids before testing is finishedand significantly altering the rheology.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisst
5、andard.1.5 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 and health practices and determine the applica-bility of regulatory limitations prior to use.2. Refer
6、enced Documents2.1 ASTM Standards:2E691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 Definitions:33.1.1 frequency sweep test, nmost rheometers have pro-grams specific for their instrument.3.1.1.1 DiscussionThe user provides a specified
7、geometry,frequency range, strain % or oscillatory stress and temperatureof the test. This test will produce the data required for thismethod.3.1.2 G, nthe elastic (storage) modulus obtained from anoscillatory test represents the energy stored during each fre-quency cycle, where the stress is divided
8、 by the correspondinglinear elastic strain.3.1.3 G”, nthe viscous (loss) modulus obtained from anoscillatory test represents the amount of energy lost duringeach frequency cycle or the imaginary part of the complexmodulus (for shear).3.1.4 geometry, nthe cone used in the test.3.1.5 shear strain, nre
9、lative deformation in shear; termoften abbreviated to shear.3.1.6 shear stress, nthe component of stress parallel to(tangential to) the area considered.3.1.7 strain, nthe measurement of deformation relative toa reference configuration.3.1.8 tan delta(d), nthe ratio of G” (viscous modulus) toG (elast
10、ic modulus).3.1.9 viscoelasticity, nthe phenomena exhibited by a liq-uid when energy is applied and once the force is released, theliquid recovers towards its original state by means of storedenergy.4. Summary of Test Method4.1 Apply the ink vehicle to the plate of a rheometer.4.2 Select the geometr
11、y (cone) and set to the required gap tothe plate.4.3 Remove the excess vehicle with the ink spatula.4.4 Set the required temperature, strain or stress and fre-quency range for the frequency sweep. (Most rheometers havea test sequence that can be pre-prepared.)4.5 Allow five minutes for temperature c
12、alibration and thevehicle to relax to its lowest energy state.NOTE 1Do not run a pre-shear sequence as this may affect results.4.6 Start the frequency sweep test.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the dir
13、ect responsibility ofSubcommittee D01.37 on Ink VehiclesCurrent edition approved June 1, 2012. Published August 2012. Originallyapproved in 2006. Last previous edition approved in 2006 as D7271 06. DOI:10.1520/D7271-06R12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontac
14、t ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Many of the definitions came wholly or in part from “An Introduction toRheology,” H.A. Barnes, J.F. Hutton, and K. Walters, Elesevier, 198
15、9.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15. Significance and Use5.1 This test method has found acceptance in the litho-graphic ink industry in predicting rheological behavior of avehicle under press conditions caused by extru
16、sion, shear-thinning rollers and dot gain recovery.5.2 This test method is restricted within the torque limita-tions and strain resolution of the rheometer used.5.3 Results may not be reproducible if the vehicle is nothomogenous.6. Apparatus6.1 Oscillatory Rheometer, capable of over 400 Newtons offo
17、rce, running at the required frequency range, and controllingstrain in the 5 to 10 % range, as well as computer and softwarecapable of running this test.6.2 Cone, preferably two cm and 2 (if the viscosity of thevehicle is too high for this geometry, other geometries may beused by agreement between c
18、ustomer and supplier).6.3 Spatula, non-abrasive to administer vehicle to the in-strument.7. Reagents and Materials7.1 Cleaning solvent.7.2 Lint free rags or tissue.8. Calibration and Standardization8.1 Calibrate the instrument using the procedure recom-mended by the manufacturer.9. Conditioning9.1 S
19、ince paste ink vehicles are shear thinning, care isneeded to ensure the test sample has not been sheared bystirring or kneading prior to testing.9.2 Allow vehicle to sit a minimum of five minutes if thevehicle has experienced shear forces before testing.10. Procedure10.1 After the instrument has bee
20、n calibrated and cleaned,separate the geometry to administer approximately1gofvehicle (or sufficient amount to completely fill geometry gap)to the center of the bottom plate.NOTE 2Do not leave air bubbles in the vehicle. If air-bubbles exist orsample does not fill entire geometry gap, either re-admi
21、nister the sampleor carefully try to eliminate them with the spatula.10.2 Set the cone and plate to the required gap. Many of therheometers will do this automatically.10.3 Using the spatula, carefully trim around cone anyexcess vehicle that may have been pushed from under the cone.10.4 Allow the veh
22、icle to equilibrate to 25C (or requiredtemperature) for five minutes. (This is the test temperature thatshould be programmed into the instrument prior to starting.)NOTE 3This method suggests that no pre-shear sequence is run. Thischanges the rheology of the sample and though the pre-shear sequencema
23、y be reproducible, the resulting data is tampered by the pre-shear.10.5 Open the Frequency Sweep Test on the computerattached to the instrument.10.6 The frequency range should be 0.1 to 1.0 Hz inlogarithmic ramp mode. Set the number of readings to 20 in adecade.10.7 The strain should be 5 to 10 %. (
24、If this instrument is acontrolled-strain rheometer, set the strain at 5 %.)10.8 Start the test as per instructions for the operationprocedure of the rheometer.10.9 The results will be over the entire frequency rangetested. The only results of interest for this method will be at 1.0Hz.10.10 Record th
25、e G, G”, and tan delta at 1.0 Hz.10.11 Clean the instrument.11. Report11.1 Report test data along with temperature, geometry size,and frequency.12. Precision and Bias12.1 PrecisionAn interlaboratory study of the rheologicaldata of two varnishes, one resin solution and one lithographicprinting ink we
26、re run by 13 rheometers in eight laboratories.12.1.1 The precision estimates here are based on one analystin each laboratory performing duplicate determinations on eachof the samples.12.1.2 Practice E691 was used in developing these precisionstatements.12.2 Repeatability (Within-Laboratory)The 95 %
27、repeat-ability of each sample is recorded in Table 1. The averagedeviation from average is 2.76 %.12.3 Reproducibility (Multilaboratory)The 95 % repro-ducibility of each sample is recorded in Table 2. The averagedeviation from average is 4.66 %.12.4 BiasThe procedure in this test method has no biasb
28、ecause there is no standard calibration fluid for this testmethod.13. Keywords13.1 frequency sweep; G; G”; oscillatory rheometer; print-ing ink vehicles; rheology; tan delta; viscosityD7271 06 (2012)2ASTM International takes no position respecting the validity of any patent rights asserted in connec
29、tion 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 time by the responsib
30、le 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 will receive careful con
31、sideration 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 ASTM International, 100
32、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 web
33、site(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).TABLE 1 RepeatabilityAverage Repeatability % from AverageVarnish AG 6933.5 106.2 1.53G” 15548.5 326.0 2.10tan delta 2.2 0.0 0.0Varnish BG 11677.3 279.5 2.39G” 20191.5 3
34、47.1 1.72tan delta 1.7 0.0 0.0Resin SolutionG 2617.1 147.1 5.62G” 6541.6 285.2 4.36tan delta 2.5 0.2 8.0InkG 3215.0 93.9 2.92G” 5372.6 241.5 4.50tan delta 1.7 0.0 0.0TABLE 2 ReproducibilityAverage Reproducibility % from AverageVarnish AG 6933.5 372.4 5.37G” 15548.5 877.1 5.64tan delta 2.2 0.0 0.0Varnish BG 11677.3 581.1 4.98G” 20191.5 856.8 4.24tan delta 1.7 0.0 0.0Resin SolutionG 2617.1 233.5 8.92G” 6541.6 433.7 6.62tan delta 2.5 0.2 8.0InkG 3215.0 211.3 6.57G” 5372.6 300.1 5.59tan delta 1.7 0.0 0.0D7271 06 (2012)3
