TM_D_6688_
_20
Designation:D668820Standard Practice forRelative Resistance of Printed Matter to Liquid Chemicalsby a Sandwich Technique1This standard is issued under the fixed designation D6688;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()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice covers the evaluation of the relativeresistance of printed matter to liquid chemicals,as evidencedby lack of discoloration,bleeding,or loss of gloss.1.2 This practice utilizes a sandwich procedure similar inprinciple to ISO/TC 130 N 589.Spotting or immersionprocedures are covered in Test Methods D1308,D1647,andD2248.1.3 This practice is applicable to prints on any flat substrateincluding paper,paperboard,metallic foil,metal plate,andplastic films,and produced by any printing process includingletterpress,offset lithography,flexography,gravure,silk screen,and non-impact.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.For specific hazard statements,see Section 7.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D1308 Test Method for Effect of Household Chemicals onClear and Pigmented Organic FinishesD1647 Test Methods for Resistance of Dried Films ofVarnishes to Water and Alkali(Withdrawn 2004)3D2248 Practice for Detergent Resistance of Organic Finishes2.2 Other Standards:ISO/TC 130 N 589 Graphic Technology-Prints and PrintingInks-Assessment of Resistance to Various Agents43.Summary of Practice3.1 Prints of the test and reference printing inks are eachsandwiched between filter paper,which has been saturated withthe specified liquid.After the agreed upon contact times,theprints and filter paper are dried and then examined forobjectionable changes such as discoloration,bleeding,or lossin gloss.The test print is then rated as better,equal,or worsethan the reference print.4.Significance and Use4.1 Many types of printed matter,notably container labels,packaging materials,magazine and book covers,must beresistant to liquid materials that may contact them advertentlyor inadvertently.This practice permits an assessment of resis-tance of printed matter to several types of liquids.4.2 The requirement that a reference print be run at the sametime as the test print minimizes effects of atmospheric condi-tions(humidity and temperature)and other variations whichmay develop.4.3 This practice can be used to determine whether newformulations are suitable for the end-use purpose and forspecification acceptance between producer and user.5.Apparatus5.1 Glass Plates,60 by 90 mm,two for each printedspecimen(minimum four per test).5.2 Petri Dish,at least 100 mm in diameter.1This practice is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.56 on Printing Inks.Current edition approved June 1,2020.Published June 2020.Originallyapproved in 2001.Last previous edition approved in 2011 as D6688 11 which waswithdrawn January 2020 and reinstated in June 2020.DOI:10.1520/D6688-20.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.5.3 Weight,1 kg.5.4 Timer,calibrated in minutes up to 24 h.5.5 Oven,capable of maintaining 50C.6.Materials6.1 Reference Print,of known resistance to the specified testliquid,cut to 20 50 mm and marked with R.6.2 Filter Paper,white neutral for qualitative analysis,