1、Designation: D7395 07 (Reapproved 2012)Standard Test Method forCone/Plate Viscosity at a 500 s-1Shear Rate1This standard is issued under the fixed designation D7395; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、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 determination of the viscos-ity of paints and related products using a cone/plate viscometerat
3、a shear rate of 500 s-1.1.2 Viscosity values obtained by this method may be used asan alternative to results from No. 4 Ford cup measurements.The values from this method do not replicate Ford cup results,but can be used for quality control, producer-user specifica-tions and viscosity reduction in th
4、e same manner that Ford cupsare used.1.3 If viscosity at a higher shear rate is needed, Test MethodD4287, which describes viscosity measurement at 10 000 to 12000 s-1may be used.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandar
5、d.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. Referenced
6、 Documents2.1 ASTM Standards:2D3925 Practice for Sampling Liquid Paints and RelatedPigmented CoatingsD4287 Test Method for High-Shear Viscosity Using aCone/Plate Viscometer3. Summary of Test Method3.1 The material to be tested is placed between the cone andplate of a cone/plate viscometer set at 25C
7、, a solvent trap islowered, and the specimen is subjected to a shear rate of 500 s-1while the viscosity is measured.4. Significance and Use4.1 This test has been used to measure viscosities ofautomotive topcoats in place of No. 4 Ford cup measurementsand has provided an equivalent ability to evaluat
8、e whether thepaint meets specifications and is sprayable.4.2 The method could be considered as an alternative to No.4 Ford cup and other efflux cup measurements for otherproducts as well.4.3 The type of viscometer described in this method givesbetter temperature control than Ford and other efflux cu
9、ps andis expected to give better precision.4.4 This test method is suitable for all paints and relatedmaterials whether they are Newtonian in behavior or not.5. Apparatus5.1 Cone/Plate Type Viscometer with cone/speed combina-tion producing a shear rate of 500 s-1and fitted with a solventtrap that co
10、vers the cone. For automotive topcoats, the viscom-eter must provide a viscosity measurement range that includes20 to 200 cP (= mPa.s) at the above-mentioned shear rate. ABrookfield CAP1000+ or CAP2000+ with a #10 cone at 100rpm shaft speed has worked well.6. Reagents and Materials6.1 Water or Solve
11、ntIf the viscometer allows manualzeroing, this should be done in accordance with the manufac-turers directions. Zeroing procedures that require liquids maybe satisfied with water or a low-viscosity solvent such asxylene or mineral spirits.6.2 Mineral OilsOne to three standard mineral oils withknown
12、viscosities (certified by an approved laboratory) lyingbetween 10 and 90 % full scale to be used for calibrating theinstrument. If a single oil is used, its viscosity should be similarto that of the materials being tested.NOTE 1Silicone oils should be avoided because of their tendency tocontaminate
13、instruments, containers and other equipment.7. Sampling7.1 Take a representative sample of the product to be testedin accordance with Practice D3925. If the sample has atendency to settle or separate on standing, then it must bestirred or shaken until homogeneous before a test specimen istaken from
14、it. However, it is appropriate to directly test a1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.24 on Physical Properties of Liquid Paints and Paint Materials.Current edit
15、ion approved Feb. 1, 2012. Published February 2012. Originallyapproved in 2007. Last previous edition approved in 2007 as D7395 - 07. DOI:10.1520/D7395-07R12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of A
16、STMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.sample that has been under constant circulation and shear in apaint system. The specimen
17、 must be free of any foreign matteror air bubbles, and its volume must be sufficient to cover theportion of the viscometer plate under the cone when the latteris brought into contact with the plate.8. Preparation of Apparatus8.1 The viscometer must be zeroed on a daily basis orotherwise before use,
18、in accordance with the operating manualfor the instrument. It may need to be re-zeroed at other timesin accordance with the manufacturers instructions.8.2 Verify the calibration of the apparatus by following theprocedure in Section 9, but using a standard refined mineral oilhaving Newtonian characte
19、ristics and a known viscosity. If theviscometer reads the correct viscosity (or within 5 % of thatvalue) with an oil whose viscosity is similar to that of thespecimens to be tested, then the viscometer readings may beused as is. If the viscometer does not give the correct viscosityfor the oil, then
20、the instrument should be returned to themanufacturer for adjustment. If necessary, a calibration curvemay be constructed by taking viscometer readings for three oilsand plotting measured viscosity versus specified (true) viscos-ity for the oils. Subsequent measurements are corrected to trueviscositi
21、es through use of the curve.8.3 Check the cones periodically for wear. Replace any conethat shows obvious wear. If there is any question of as towhether the cone has changed, verify the apparatus as in 8.2.8.4 The viscosity measurement must be done at a closelycontrolled temperature of 25 6 0.1C.8.5
22、 Make sure that the combination of cone and speed thatis selected for the measurements gives the shear rate of 500 s-1.9. Procedure9.1 Check that the cone is attached properly and the setscrew hand tightened to snug. Do not over tighten. With thecone in the down position (in contact with the plate),
23、 turn theinstrument on and allow it to warm up for at least 10 min. If theviscometer is a multi-temperature instrument, be sure that it isset at 25.0C. Confirm that readings will be in cP (mPa.s).9.2 Raise the cone to the up position. Transfer a suitableamount of the product to be tested to the cent
24、er or near thecenter of the plate with a pipette, syringe or other precisiontransfer device. If the viscometer manufacturer specifies atarget specimen volume, transfer this amount (60.005 ml).NOTE 2Dispensing of 0.190 6 0.005 ml with a precision pipette hasbeen found to work for a Brookfield CAP1000
25、+/2000+ using a #10 cone,and takes hold-up in the pipette tip into account. The actual target amountfor a #10 cone is 0.170 ml.Take care to avoid the inclusion of air bubbles. Lower thecone to the down position quickly to minimize solvent loss andconfirm that the specimen is pressed out slightly (at
26、 least 1mm) around the entire circumference of the cone. Lower thesolvent trap over the cone and onto the plate.NOTE 3If specimen material is not observed around the entirecircumference of the cone, Stop! Clean up, resample and deposit a newspecimen onto the plate to avoid producing a low viscosity
27、value. Verifythat the entire specimen is being dispensed from the pipette, syringe orother transfer device.9.3 Wait for 60 s to allow the specimen to reach 25.0C andequilibrate at that temperature. If the instrument has thecapability of setting times for specific procedures, set theHOLD time for 60
28、s or make certain that the specimen hasequilibrated at 25.0C. Set a hold time of at least 20 s.Whichever HOLD time approach is used, make certain that thespecimen actually is tested (RUN) at 25.0C. Set the RUN timefor 15 s (at 100 rpm; slower rotation speeds may require longerrun times, in accordanc
29、e with manufacturers recommenda-tion).9.4 Start the cone rotating (make sure that the solvent trap isnot touching the cone shaft) and record the reading after 15 s.9.5 Raise the solvent trap, followed by the cone.9.6 Clean both the cone (in-place) and the plate carefully,using a clean, lint-free sof
30、t cloth or tissue and a suitablesolvent. Take care to remove all the test material and cleaningsolvent, but minimize sideways pressure on the cone shaft toavoid bending it. Do not use cleaning utensils that may damagethe apparatus. Metal cleaning tools must never be used.10. Report10.1 Report the fo
31、llowing information:10.1.1 Reference to this test method and the viscometerused.10.1.2 Identification of the product under test.10.1.3 Cone used.10.1.4 Viscometer (rpm) speed used.10.1.5 Test result in cP (= mPa.s) to the nearest 0.1 cP.11. Precision and Bias11.1 PrecisionNo ASTM interlaboratory tes
32、ting has yetbeen carried out on this method, but estimates of precisionhave been made based on experience with the method.11.1.1 RepeatabilityTwo test results in the range 20 to200 cP obtained by the same operator should be consideredsuspect if they differ by more than 3 % relative.11.1.2 Reproducib
33、ilityTwo results in the range 20 to 200cP obtained by operators in different laboratories should beconsidered suspect if they differ by more than 10 % relative.11.2 BiasSince there is no accepted reference materialsuitable for determining the bias for the procedure in this testmethod, bias has not b
34、een determined.12. Keywords12.1 No. 4 Ford cup-alternative to; rheology-paints/relatedcoatings/materials; viscometer-cone/plate; viscosity-paints/related coatings/materialsD7395 07 (2012)2ASTM International takes no position respecting the validity of any patent rights asserted in connection with an
35、y 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 responsible technical
36、 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 consideration a
37、t 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 Barr Harbor
38、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 ASTM website (www.astm.org/COPYRIGHT/).D7395 07 (2012)3
