1、A Referencenumbe r ISO12636:1998 (E) INTERNATIONAL STANDARD ISO 12636 Firstedition 19980715 GraphictechnologyBlanketsforoffset printing TechnologiegraphiqueBlanchetspourimpressionoffsetISO12636:1998(E) ISO1998 Allrightsreserved.Unlessotherwisespecified,nopartofthispublicationmaybereproduced orutiliz
2、edinanyformorbyanymeans,electronicormechanical,includingphotocopyingand microfilm,withoutpermissioninwritingfromthepublisher. InternationalOrganizationforStandardization Casepostale56 CH1211Genve20 Switzerland Internet isoiso.ch PrintedinSwitzerland ii Contents Page 1 Scope 1 2 Termsanddefinitions .
3、 1 3 Requirements 2 4 Testmethods . 4 AnnexA (informative):EquivalenceofSIvaluestoFPSvalues 8ISO ISO12636:1998(E) iii Foreword ISO(theInternationalOrganizationforStandardization)isaworldwide federationofnationalstandardsbodies(ISOmemberbodies).Theworkof preparingInternationalStandardsisnormallycarri
4、edoutthroughISO technicalcommittees.Eachmemberbodyinterestedinasubjectforwhich atechnicalcommitteehasbeenestablishedhastherighttoberepresented onthatcommittee.Internationalorganizations,governmentalandnon governmental,inliaisonwithISO,alsotakepartinthework.ISO collaboratescloselywiththeInternational
5、ElectrotechnicalCommission (IEC)onallmattersofelectrotechnicalstandardization. DraftInternationalStandardsadoptedbythetechnicalcommitteesare circulatedtothememberbodiesforvoting.PublicationasanInternational Standardrequiresapprovalbyatleast75%ofthememberbodiescasting avote. InternationalStandardISO1
6、2636waspreparedbyTechnicalCommittee ISO/TC130, Graphictechnology . AnnexAofthisInternationalStandardisforinformationonly.ISO12636:1998(E) ISO iv Introduction Theblanketisanessentialpartofeveryoffsetprintingpress.Itsproperties exertaprofoundinfluenceonthemechanicalconditionswithinthepress andthevisua
7、lcharacteristicsoftheprintsproduced.Itisthereforeusefulto providetestmethods,unifieddata,andtolerancesforsomeessential propertiesoftheblankets.Thispermitsthesupplierstostatepropertiesof blankettypesinaunifiedandwellknownmanner.Italsohelpstheprinter toselecttheappropriateblankettypeforaparticularpres
8、stypeorpress condition.Afurtherbenefitisthatthedesignofprintingpressescanbe basedonblanketdataresultingfromunifiedtestmethods.INTERNATIONALSTANDARD ISO ISO12636:1998(E) 1 GraphictechnologyBlanketsforoffsetprinting 1Scope ThisInternationalStandarddefinesvocabulary,specifiestestmethods,characteristics
9、,orderingandlabeling informationforblanketsforoffsetprinting.ThisInternationalStandarddoesnotapplytountensionedorunclamped blanketsforoffsetprinting,noroffsetprintingsleevesusedwithgaplesspresses. 2 Termsanddefinitions ForthepurposesofthisInternationalStandard,thefollowingtermsanddefinitionsapply. 2
10、.1 acrossdirection directionofthesideoftheblanketasintendedtobeappliedperpendiculartothedirectionofrotation 2.2 aroundthecylinderdirection directionofthesideoftheblanketasintendedtobeappliedinthedirectionoftherotation 2.3 averagethicknes meanoffourmeasurementsonacutblanketwherethemeasurementshavebee
11、nmadeonthepointsindicatedin figure1,namelyon2diagonallyopposedcornersandoneeachatthemiddleofthetwosidesthatare perpendiculartoeachotherwithinarighttriangle Figure1Thicknessmeasurementpoints 2.4 blanket compositebody,consistingofcoatedcarriermaterial,e.g.fabric,usedfortransferoftheprintinginkfromthef
12、orme ontomaterialtobeprintedon,e.g.foroffsetprintingISO12636:1998(E) ISO 2 2.5 compressibilitydeflection averagethicknessreductionofablanketmeasuredunderaspecificpressure,expressedinmillimetres 2.6 compressibilityindentation averagedepthofimpression, I,inablanketmeasuredunderaspecificpressure,expres
13、sedinmillimetresoras percentageindentation I p 2.7 elongation increaseofthedimensioninthearoundthecylinderdirectionofablanketunderlongitudinalstress,expressedin percentofthelengthataspecifiedforceperwidth 2.8 packing underlaymaterialplacedundertheblankettoadjusttheeffectivethicknessoftheblanketonpre
14、ss 2.9 printingsurface sideoftheblanketthatisusedforthetransferofprintingink 2.10 shrinkage decreaseinthicknessduetoexposureoftheblanketprintingsurfacetoaliquid,expressedasapercentageofthe originalblanketthickness,orasanabsolutethicknessdecreaseinmillimetres 2.11 sizes dimensions(thickness,widthandl
15、ength)ofacutreadytouseblanket 2.12 swelling increaseinthicknessduetoexposureoftheblanketprintingsurfacetoaliquid,expressedasapercentageofthe originalblanketthickness,orasanabsolutethicknessincreaseinmillimetres 2.13 tensilestrength forceperunitwidthrequiredforbreakingablanketunderlongitudinalstressi
16、nthearoundthecylinderdirection 2.14 thicknessvariation differencebetweenthegreatestandthesmallestthicknessvalueinmillimetres 3Requirements 3.1Dimensions 3.1.1Thickness Thetestmethodaccordingto4.1shallbeused.Forapplicationswithpackingthenominalthicknessshallbe 1,68mmor1,95mm.Forapplicationswithoutpac
17、kingthenominalthicknessshouldbeagreeduponbetweenthe supplierandtheuseroftheproduct. NOTE Thenominalthicknessshouldbestatedintechnicaldescriptionsandwhenordering. Thethicknessvariationsofblanketswithanareanotinexcessof1,5m 2 shallbelessthan0,02mm,thoseof greatersizesshallbelessthan0,03mm.Noindividual
18、thicknessmeasurementshallyieldavaluewhichdeviates morethan0,05mmfromtheorderedthickness.ISO ISO12636:1998(E) 3 3.1.2 Accuracyofwidthandlength Ifoneofthesidesis1morless,thetoleranceshallbe3mm,otherwiseitshallbe4mm. 3.1.3Plan view Thesidesoftheblanketshallformrightangles.Thedifferencebetweenthelengtho
19、fthediagonalsandthelength ofanytwoparallelsidesshallnotexceed0,5%. 3.2 Materialsandsurfacefinish Nospecificationsaregiven.Thematerialformulationandsurfacefinisharethechoiceofthemanufacturerandmay bestatedintechnicaldescriptionsbythesupplier.Thesurfacefinishmayvary,e.g.cast(molded)orground (buffed).
20、3.3Elongation Theelongation Eshallbelessthan1,5%.Thetestmethodaccordingto4.2shallbeusedoranyothermethod whereresultscanbecorrelatedtothoseofthetestmethod. 3.4Tensile strength Forallblanketsofthickness1,68mmormore,thetensilestrengthshallbegreaterthan40N/mm.Thetestmethod accordingto4.3shallbeusedorany
21、othermethodwhereresultscanbecorrelatedtothoseofthetestmethod.For blanketsoflowerthicknessnospecificationisgiven. 3.5Compressibility Nospecificationisgiven.Eithertestmethodaccordingto4.4or4.5shallbeused. NOTE Theuseofcompressibilitydeflectionorcompressibilityindentationmethodisthechoiceofthemanufactu
22、rerand maybestatedbythesupplier. 3.6 Thicknesschange 3.6.1 Swellingorshrinkageduetoprintinginkingredients Thethicknesschange D Tduetoexposuretoprintinginkingredientsshallnotexceed4%maximumswellingor2% maximumshrinkage.Thetestmethodaccordingto4.6foreachpropertyshallbeused. 3.6.2 Swellingand/orshrinka
23、geduetoblanketwashes Whentestingblanketwashesfortheircompatibilitytoanoffsetprintingblanket,itistheoptionoftheblanket manufacturertoreporttestresultsusingthetestmethodaccordingto4.6foreachproperty. Whenchoosingablanketcleaningmaterialforcomposition,itshouldbetestedforcompatibilitywiththeblanket. NOT
24、E Thechoiceofaproperwashisadifficultdecisionduetotheneedtobalanceeffectivenessversussafetyand environmentalneeds. 3.7Hardness TheoverallhardnessandthemicrohardnessarenotspecifiedinthisInternationalStandard.Theyarethechoiceof themanufacturer. 3.8 Cutblanketmarkings Onthenonprintingsideofthecuttosizeb
25、lanketthefollowingshouldbereported: a)Blanketdimensions(averageactualthickness,widthandlength),indicatingwhichdimensionisthe aroundthecylinderdirection.Iftherecordedthicknessisnominalthisshallbestated.ISO12636:1998(E) ISO 4 b) Thebatchcontrolnumber. c) Thenameofthemanufacturerorthesupplierandtheblan
26、ketbrandortradename. 4Test methods 4.1Thickness Placetheblanketbetweentwoparallelflatcirculardisksof100mm 2 to200mm 2 area.Loadthediskswithaforce thatproducesapressureof(605)kPa.Measurethegapbetweenthedisksinm illimetres.Othermethods,e.g. continuousones,maybeusedinsteadiftheresultscanbecorrelatedtot
27、hoseofthemethodspecified. 4.2Elongation Cuta50mmby350mm(minimum)samplefromtheblanketwiththelongdirectionparalleltothearoundthe cylinderdirection.Applytothesampletwobenchmarks250mmapart.Clamptheshortersidesofthesampleina tensiletestingapparatuswithajawseparationof300mm(minimum),andapplyastaticlinefor
28、ceof10N/mm. After10mindwelltime,determinethedistance Lbetweenthebenchmarksunderload.Calculatethepercentage elongationfrom E L L L = 100 % - 0 0 whereL 0 =250mmbenchmarksand L isthelengthafter10minunderload. 4.3Tensile strength Cuta50mmby300mm(minimum)samplefromtheblanketwiththelongdirectionparallelt
29、othearound thecylinderdirection.Clamptheshortersidesofthesampleintoatensilestrengthtestingapparatuswitha minimumjawseparationof200mm.Applytheloadwithajawseparationspeedof50mm/min.Increasetheloadtill thebreakoccurs,readtheforceatbreak.ThetensilestrengthisexpressedinN/mm. 4.4 CompressibilityDeflection
30、 Key 1 Upperfaceofcompressionapparatus 2 Circularsample700mm 2 3 Lowerface d Distance10mm(minimum) Figure2CompressibilityDeflection (nottoscale)ISO ISO12636:1998(E) 5 a) Indicationofblanketcompressibilityisexpressedasanabsolutedeflectionatapredeterminedpressureof 2000kPa. b) Apparatus:Continuousload
31、ingapparatus(tensometer). c) Useacompressionloadcellwithparallelflatsurfacesoracompressioncage(maximumdiameter100mm). d) Samplesize(70010)mm. e) Headspeed:1mm/min. f) Zeropoint:(605)kPa. g) Compressthesampleuntilaloadof2060kPaisreached,recordingthedeflectionatthe1stand5thcyclesat 1060kPaand2060kPa.
32、h) Reportthe5thcycledeflectionvaluesat1060kPaand2060kPafromanaverageof4samples. NOTE Duetomachinedeflectioninherentinalltestequipment,careshouldbetakentocompensateforthisdeflection whenreportingresults.Thisdeflectionmaybeinthefixtures(pressioncage)aswellastheloadcell.Atestwitha flat noncompressiblec
33、irculardisk(70010)mm 2 isruntodeterminedeflectionofthetestingsystematdifferentloads.Thisdisk shouldbeofminimumthicknesssuchthatallforceisbornebythediskduringthetest.Suggestedmaterialforthisdiskisbr ass orsteel.Thestressstraincurveisusedtocorrectforthisintrumentdeflectioninordertoindicatecorrectblank
34、et compressibility. 4.5 CompressibilityIndentation Key 1 Upperfaceofcompressionapparatus 2 Circularloaddiskof100mm 2 3 Sample 4 Lowerface d Distance9mm(minimum) Figure3CompressibilityIndentation (nottoscale) a) Indicationofblanketcompressibilityisexpressedasanabsoluteindentationatapredeterminedpress
35、ureof 1000kPa. b) Apparatus:Continuousloadingapparatus(tensometer)utilizingparallelflatsurfacesandacircularloaddiskof 100mm 2 . c) Samplesize(70010)mm 2 . d) Zeropoint:(605)kPa.ISO12636:1998(E) ISO 6 e) Recordthedistancebetweentheloaddiskandthelowerfaceinmillimetresatthepreloadof(605)kPa.The recorde
36、dvalueistheinitialpreloadthickness D 0 . f) Headspeed:1mm/min. g) Compressthesampleuntilaloadof1060kPaisreachedrecordingthedistancebetweentheloaddiskandthe lowerfaceinmillimetres.Therecordedvalueistheindentedthickness D 1 . h) Repeattheloadingthreetimes,thendeloadto60kParecordingthedistancebetweenth
37、eloaddiskandthe lowerfaceinmillimetres.Therecordedvalueisthefifthcyclepreloadthickness D 04 . i) Compressthesampleafifthtimeuntilaloadof1060kPaisreachedandrecordthedistancebetweentheload diskandthelowerfaceinmillimetres.Therecordedvalueistheindentedthickness D 5 (seefigure4). j) Reportvaluesfromanav
38、erageof4samples. Key a)Thickness b) Numberofloadcycles c)Unloaded thickness d)Loaded thickness Figure4TestprocedureforCompressibilityIndentation Reportthefollowing: Theinitialpreloadthickness D 0 . Theabsoluteindentation( l 1 )atthefirstloading, D 0 D 1 . Theabsoluteindentation( l 5 )atthefifthloadi
39、ng, D 04 D 5 . Alternativelythepercentageindentation I p canbereported;thenthepercentageindentationatthefirstloading is p1 01 0 100 I = DD D - % Thepercentageindentationatthefifthloadingis p % 5 04 5 04 100 I = DD D - NOTE Duetomachinedeflectioninherentinalltestequipment,careshouldbetakentocompensat
40、eforthisdeflection whenreportingresults.Thisdeflectionmaybeinthefixtures(pressioncage)aswellastheloadcell.Atestwithth e 100mm 2 circularloaddiskbetweentheparallelflatfacesisruntodeterminedeflectionofthetestingsystematdifferentloads. Thestressstraincurveisusedtocorrectthisinstrumentdeflectioninordert
41、oindicatecorrectblanketindentation.ISO ISO12636:1998(E) 7 4.6Thickness change 4.6.1 Swellingorshrinkageafterexposuretoatestliquid Cuta50mmdiameteror50mmsquaresamplefromablanket.Measuretheinitialthickness T o oftheblanket usingthetestmethodaccordingto4.1.Clampthesampleintoatestfixturewhichprotectsthe
42、edgeand nonprintingsurfacefromcontactwiththetestliquid(seefigure5).Thetestliquidshallbeatleast3mmdeep. Exposetheprintingsurfacetothetestliquidforaperiod tatatemperature J (4.6.3forinksand4.6.4forwashes). Removethesamplefromthetestfixture,cleanoffexcessliquidandmeasurethethickness T 1 usingthemethodas specifiedin4.1.Calculatethepercentagethicknesschangefrom: D = 1 10 0 100 T TT T - % where D T 1 isthepercentagechangeaftertime t. T 1 is
