1、Designation: D332 87 (Reapproved 2015)Standard Test Method forRelative Tinting Strength of White Pigments by VisualObservation1This standard is issued under the fixed designation D332; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, 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 describes the procedure for determin-ing the relative tinting strength of white pigment
3、s by visualassessment of blue tints.1.2 This test method is applicable only for comparing thetest pigment with a reference standard of the same type andgrade.NOTE 1Test Method D2745 describes a procedure for instrumentalevaluation of black tinted samples.1.3 The values stated in SI units are to be r
4、egarded as thestandard. The values given in parentheses are for informationonly.1.4 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 det
5、ermine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D262 Specification for Ultramarine Blue Pigment (With-drawn 2005)3D2745 Test Method for Relative Tinting Strength of WhitePigments by Reflectance Measurements3. Summary of Test Method3.1 Speci
6、fied amounts of white pigment and blue tintingpigment are dispersed together in oil using a glass hand mulleror an automatic muller. Both the test and standard pigments aretreated identically. The pastes are drawn-down together on apanel and visually assessed for tinting strength. To obtain anumeric
7、al rating of tinting strength, dispersions with thestandard white pigment and more or less of the tinting pigmentare made until the lightness of the test pigment paste ismatched. The weight of the tinting pigment is used to calculaterelative tinting strength.4. Significance and Use4.1 This test meth
8、od is used as a referee method and forquality control. The vehicle (oil) for preparing the dispersionsand the tinting pigment (ultramarine blue) are specified butother vehicles and tinting pigments can be used. Any suchchanges in the test method must be agreed upon between thepurchaser and the selle
9、r.4.2 The results obtained with a muller do not necessarilyagree with an industrial situation where different dispersingconditions exist. However, dispersing with a muller is a fastand relatively inexpensive way of testing tinting strength forroutine quality control.5. Apparatus5.1 Balance, laborato
10、ry-type, sensitive to 0.1 mg, equippedwith a counter-balanced watch glass.5.2 Buret, 1-mL capacity, stopcock controlled, graduated in0.1-mL divisions, or other suitable dispensing apparatus with adelivery accurate to 0.05 mL.5.3 Glass Hand MullerA weighted glass hand muller withbeveled edge having a
11、 total weight of 6.8 kg (15 lb) and agrinding face of from 70 to 75 mm (234 to 3 in.) in diameter.The face shall be free of blowholes and other imperfections andkept roughened by lightly grinding with No. 303 optical emery,or its equivalent, and turpentine.5.4 Rubbing SurfaceA ground glass plate, at
12、 least 355 by510 mm (14 by 20 in.), the surface of which is kept roughenedby lightly grinding with No. 303 optical emery, or itsequivalent, and turpentine.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct res
13、ponsibility ofSubcommittee D01.26 on Optical Properties.Current edition approved Dec. 1, 2015. Published December 2015. Originallyapproved in 1931. Last previous edition approved in 2011 as D332 87 (2011).DOI: 10.1520/D0332-87R15.2For referenced ASTM standards, visit the ASTM website, www.astm.org,
14、orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor D
15、rive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.5 Automatic Muller, automatic,4equipped with a weightthat exerts a permanent 50-lbf (220-N) force and an additionalweight exerting a 50-lbf making a total of 100-lbf (445-N). Thetwo glass plates shall be kept sharp by removing from
16、 themachine and grinding them face-to-face with No. 303 opticalemery or equivalent, and water.5.6 SpatulaA flexible spatula having a chromium-platedor plastic blade 75 to 150 mm (3 to 6 in.) long.5.7 Panels of bright tin, glass, or white-lacquered card-board.5.8 ScraperAFrench scraper or stiff scrap
17、ing knife havinga blade that is about 75 to 100 mm (3 or 4 in.) wide with astraight edge.6. Materials6.1 Tinting MaterialUltramarine blue conforming toSpecification D262 or a grade agreed upon by the purchaserand the seller.6.2 OilRefined linseed oil with an acid number of ap-proximately 4.6.3 Refer
18、ence StandardA standard white pigment of thesame type and grade as the pigment to be tested, as agreedupon between the purchaser and the seller.7. Procedure AGlass Hand Muller7.1 Weigh2gofthestandard white pigment and the amountof ultramarine blue listed in Table 1 to 62 mg. Transfer theweighed port
19、ions of white and blue pigments to the ground-glass plate. Add the amount of oil specified in Table 1 from theburet (Note). Be sure to allow the buret to drain to its true levelbecause variations in the amount of oil decrease the precisionof the test. Work the pigments and oil into a paste with thes
20、patula; then rub up the paste with the glass hand muller,spreading it over an area 75 to 100 mm (3 to 4 in.) wide andfrom 305 to 380 mm (12 to 15 in.) long. In counting the rubs,one stroke up and one stroke back is considered one rub.Allowthe muller to travel up one side and back the other side,twis
21、ting it slightly at the top and bottom of each stroke. Aftereach 25 rubs with the muller, “pick up” the paste with thespatula by scraping the face of the muller and gathering thepaste on the slab into a mound. Repeat until the paste has beengiven 100 rubs.NOTE 2Where the resulting paste is too fluid
22、 or too thick for mulling,adjust the quantity of oil to give a workable paste and prepare a new paste,mulling as before. Report the amount of oil used.7.2 Work2gofthetest pigment in exactly the same manneras prescribed in 7.1 for the standard, using the same amount oftinting material and oil.7.3 Spr
23、ead the paste of the standard and test pigments inparallel contiguous rectangular areas on the panel, each about25 mm (1 in.) wide and 50 mm (2 in.) long. Use the scraper tosmooth the surface of the pastes (here called “draw-downs”) bydrawing the scraper lightly over the pastes to give a straightand
24、 even line of contact between them. Keep the drawn-downssufficiently thick to obscure the panel.7.4 Immediately examine the draw-downs of the two pastes,on the top side only, for relative lightness of tint. If the sampleis lighter than the reference standard it has greater tintingstrength. If the sa
25、mple differs appreciably from the referencestandard in lightness of tint, and if a numerical rating is desired,prepare other pastes of the reference standard white pigmentusing different amounts of the tinting material. Make a draw-down of the sample paste with each standard as described in7.3. Sele
26、ct the draw-down in which the standard pigment pastemost closely matches the test pigment paste in lightness. Usethe weight of tinting material in this method to calculate thetinting strength of the test pigment.8. Procedure BAutomatic Muller8.1 In order to minimize the effect of the difference ingr
27、inding of the area near the center of the plates as comparedto the area near the periphery of the plates, draw two concentriccircles under the base plate of the muller in such a way thatthey show clearly through the plate. These circles can be drawneither on a paper inserted under the plate, or draw
28、n directly onthe bottom of the plate. The inner circle should be 63 mm (212in.) in diameter and the outer circle 115.3 mm (412 in.) indiameter.8.2 Carefully weigh the pigment as described in 7.1, trans-ferring the pigment to the base plate of the muller. Add the oiland work the pigment and oil into
29、a paste with the spatula.Distribute the paste within the area between the two concentriccircles on the plate, close the muller, and add a 23-kg (50-lb)weight (to make a total weight of 45 kg (100 lb) pressing theplates together. Carry out three mulling stages of 50 revolu-tions each, collecting the
30、paste from both plates with thespatula after each stage, spreading it around the path on thelower plate and wiping the spatula on the upper plate as before.8.3 Continue the treatment of the paste of the test andstandard pigments as described in 7.2, 7.3, and 7.4.9. Calculation9.1 Calculate the tinti
31、ng strength of the sample as follows:TS 5 B/A! 3T4The sole source of supply of the muller known to the committee at this time isHoover Color Corp., P. O. Box 218, Hiwassee, VA 24347. If you are aware ofalternative suppliers, please provide this information to ASTM InternationalHeadquarters. Your com
32、ments will receive careful consideration at a meeting of theresponsible technical committee,1which you may attend.TABLE 1 Quantities of Materials for Tinting Strength TestsPigment TypeWeight ofPigment,gWeight ofUltramarineBlue TintingPigment, gAmount ofOil, mLWhite Lead 2 0.2 0.5Zinc oxide 2 0.2 0.7
33、Zinc oxide, leaded 2 0.2 0.5Titanium dioxide(anatase) 2 0.4 1.0(rutile) 2 0.4 0.9D332 87 (2015)2where:TS = tinting strength of the test pigment, lbf (or N),A = weight of tinting material used with standard to giveequality of tint, g,B = weight of tinting material used with test sample, g, andT = arb
34、itrary tinting strength value given to the standard.10. Precision and Bias10.1 The precision and bias are to be determined.11. Keywords11.1 tinting strength; visual; white pigments; white pigmentstrengthASTM International takes no position respecting the validity of any patent rights asserted in con
35、nection 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 respon
36、sible 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
37、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 ASTM International, 1
38、00 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:/ 87 (2015)3
