ASTM_D_780_-_95_2003.pdf

Designation:D 780 95(Reapproved 2003)Technical Association of Pulp andPaper IndustryStandard Method T 462 Su 72An American National StandardStandard Test Method forPrinting Ink Permeation of Paper(Castor Oil Test)1This standard is issued under the fixed designation D 780;the number immediately following the designation 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(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the absor-bancy rate of paper for printing inks having an oil vehicle butis normally used only for easily permeable papers such asnews,book,and mimeograph.1.2 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 Documents2.1 ASTM Standards:2D 585 Practice for Sampling and Accepting a Single Lot ofPaper,Paperboard,Fiberboard,or Related ProductsD 685 Practice for Conditioning Paper and Paper Productsfor Testing3.Summary of Test Method3.1 This test method is performed by measuring the timerequired for a drop of USP castor oil to produce a uniformtranslucent spot on the under side of the test specimen bypermeation through the specimen.4.Significance and Use4.1 Acorrelation has been established between the results ofthis test and the printing of uncoated papers.5.Apparatus and Materials5.1 Viewing Box(Fig.1),having an open front;a top ofsmooth sheet material,with a 20-mm diameter hole forobserving the specimen;a ground-glass partition parallel withthe front of the box to prevent excessive heat from affecting thetest results;a 25-W electric bulb placed in back of the partitionfor illuminating the specimen;and an adjustable mirror nearthe bottom and centered on the observation hole in the top ofthe box.5.2 Separatory Funnel or Buret,with a tip of such diameterthat 25 drops of distilled water delivered at 21C will have avolume of 1 mL.The funnel or buret is suspended with the endof the tip approximately 45 mm above the test specimen.5.3 Small Bottle Cap,with black interior,having its diam-eter in excess of 20 mm.5.4 TimerStopwatch or electric timer.5.5 Castor Oil,USP,the temperature of which is maintainedat 23 6 1C.NOTE1The viscosity of USP castor oil has been found to varysomewhat.Accordingly,for particular tests,agreement should be reachedregarding the specific sample of oil to be used.6.Test Specimen6.1 Obtain a sample of the paper in accordance withPractice D 585.From each test unit of the sample cut at leastten square test specimens each about 50 mm on a side.Identifyfive of the specimens on the wire side,and the other five on thetop side.7.Conditioning7.1 Precondition,condition,and test the specimens in anatmosphere in accordance with Practice D 685.8.Procedure8.1 Place a specimen over the hole in the top of the box.Suspend the funnel with the end of the tip approximately 45mm above the test specimen.Place a little castor oil in thefunnel and slowly open the cock until a drop of castor oil fallsfrom the funnel or buret upon the specimen.Close the cock.Cover the oil drop with a cap having a black interior to providesharper determination of the end point.Observe the undersideof the paper in the mirror and measure the time interval fromthe instant of contact until the spot of oil reaches a uniform andmaximum translucency.(End point appearance will differdepending upon the amount of high refractive index pigmentpresent in the paper being tested.)8.2 Make five test determinations on each side of the paper.1This test method is under the jurisdiction of ASTM Committee D06 on Paperand Paper Products and is the direct responsibility of Subcommittee D06.92 on TestMethods.Current edition approved Jan.15,1995.Published March 1995.Originallypublished as D 780 44 T.Last previous edition D 780 87(1991).2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards 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.9.Report9.1 Report the following information:9.1.1 Maximum,minimum,and average time of penetrationfor the five tests for each side of the paper,to the nearestsecond,9.1.2 Average spot diameter at completion of the test,inmillimetres,for each side of the paper,and9.1.3 Specifics regarding the castor oil used(see 5.5).10.Precision and Bias10.1 PrecisionIt is not practicable to specify the precisionof this test method because the precision is known to be highlydependent upon the type of the paper,its formation,and otherfactors.Should users of this