网板印刷技术.ppt

網板印刷技術教育訓練ScreenPrintingTechnology,網板印刷圖解說明,刮刀以一定的方向推動油墨使其通過網目乳劑確定圖騰的界限及襯墊影響出墨的是網目、網徑及乳劑,基板(承印物)Substrate,刮刀Squeegee,油墨Ink,網目(網孔)ScreenMesh,乳劑Emulsion,細網目FineMesh,粗網目CoarseMesh,網印術語,網目MeshCountNumberofwiresperlinearinch/cminascreenmesh網目角度MeshAngleOrientationor“bias”ofwiremeshrelativetothescreenframe網版張力MeshTensionLeveloftightnessinscreenorresistancetodeflection(牛頓/公分)感光乳劑EmulsionPolymercoatinginthemeshthatdefinesandgasketsprint刮刀SqueegeePolymerbladeusedtomoveinkacrossandthroughmesh刮刀硬度DurometerHardnessorflexibilityofsqueegeeoremulsion(ShoreAunits)刮刀壓力SqueegeePressureAmountofeffective,downwardforceappliedbythesqueegee刮刀行程SqueegeeTravelMechanicallimittohorizontalsqueegeetravelacrossscreen刮刀下刀量DownstopMechanicallimittoverticalsqueegeetraveltothesubstrate,攻角AttackAngleForwardprintingangleofsqueegee(affectshydraulicforces)離板SnapOffDistancebetweenundersideofscreenandsubstratesurface回墨FloodCoatsmeshsurfacewithfreshinkinpreparationfornextprint一次性印刷Print/FloodPrintinginonedirectionwithafloodcoatintheoppositedirection同向印刷二次Print/PrintPrintingsubstratew/twopassesofink,oneineachdirection異向印刷二次Print/AlternatePrintingsubstratew/onepassofink,inalternatingdirections刮清網版油墨ScavengingSqueegeeedgescrapessomeinkfrommeshopeningsaftertransfer黏度ViscosityInternalresistanceofafluidrelativetomotionunderexternalshear流變RheologyCharacterizationofviscousflowrelativetoshearforcesand/ortime,網印術語,網版結構說明,可再使用的網框Re-usableFrame,網布+底層乳劑ScreenMesh+BaseCoatEmulsion,乳劑遮蔽區EmulsionBuildup,線路/圖案開口印刷區PatternOpening,網板感光乳劑,聚合物與感光劑BasePolymer1/2曝光速度，改善防溶劑，90天的耐儲時間雙固化型“Dual-Cure”較寬的曝光範圍提供最佳線的解析度，可用於許多特殊種類,未感光網版使用(For“Pre-Sensitized”screens),網版印刷的製版工藝ApplicationMethods直接塗佈LiquidDirect使用最廣，但圖文輪廓邊緣易出現鋸齒現象，線條不太光滑但耐磨損直接製版法DirectCapillaryFilm首先在繃緊的網上塗佈感光膠。陽片上的空白區域經光照射后在網版上形成感光固化膜陽片上圖文區域阻擋光線，網版上的膠膜未感光用水顯影后，呈現出通透的網孔，可提供較不粗糙的圖文間接製版法IndirectFilm類似直接法，間接法的感光膠不是塗佈在網版上，而是預先塗佈在薄片基上對細網絲處理較困難，製版成本較高，耐印力低直接/間接製版法Direct/Direct(Indirect)先在薄片基上塗佈感光膠，把感光膠膜貼到繃緊的網上在網框內再塗佈感光膠，使感光膜同絲網粘合，吹乾後揭去薄片基感光膠膜完全附著在網版上。,網板感光乳劑,LiquidDirect,網板感光乳劑,網版Screen,感光乳劑Emulsion,塗佈,乳劑塗佈,1.繃好的網版最少存放24小時再使用2.全面脫脂：使用軟刷且具有一定壓力的水進行清洗3.在低於40的溫度下烘乾4.提前12小時將感光膠配好5.塗膠的面積至少要比網框內徑小106.烘乾網版時，應將印刷面朝下擺放,底片對位AlignArtwork,底片藥膜對網版藥膜,網版,底片(藥膜面),1.保持曝光機的玻璃真空橡皮布的清潔2.檢查底片是否正確3.藥膜面是否貼合網版4.黑度是否達到要求，擺放是否正確5.曝光機有足夠的抽真空時間6.已曝光的網版遠離光源,UV-網版曝光,網版Screen,底片,感光乳劑,曝光不足：1.感光膠層減薄太多容易出現針孔2.圖紋或導線的邊沿容易産生鋸齒3.網版的耐印次數下降4.網版回收難，在脫過膜的絲網上易出現圖紋陰影曝光過頭：1.圖紋會失真，細線條會更細，低調網點擴大，高光網點縮小2.沖顯困難，漏空部分出現殘膠從而使油墨不過網孔3.模版變脆。,顯影parallelismmustbeaccurate對印刷設定非常敏感，斜刮提供最大的適應性(印刷壓力、印刷下刀角度，等)Muchmoresensitivetoprintersettings(pressure,angleofattack,etc.)使用更精確的印刷應用(印刷區小、纖細網徑/間隔)Usedformorepreciseprintingapplications(smallarea,finelines/spaces),長方形直角刮刀Rectangularor“Flexible”較少敏感對刮刀平行及基板平整的變動Lesssensitivetovariationsinparallelismandsubstrateflatness較少敏感對印刷設定(少控制在膜厚方面)Lesssensitivetochangesinprintersettings(lesscontroloverthickness)主要使用在大印刷面積，高速印刷設備Usedmainlyforlargeareagraphics,high-speedprintingequipment,雙層或三層刮刀DualorTriple“Composite”Durometer堅固或高硬度支持降低刮刀彈性Rigidorhighdurometerbackingreducesoverallsqueegeeflexibility允許柔軟硬度材料在正邊緣做大部份工作Allowssofterdurometermaterialattheveryedgetodomostofthework對印刷設定非常敏感Sensitivetochangesinprintersettings使用導電油墨印刷在大面積要更精確Usedtoprintlargeareaelectronicinkswithmoreprecision,刮刀通常是由聚氨酯製成,絲網印刷技能,優勢Advantages:在不同基板添加電路製程Additiveprocessforelectroniccircuitryonvarioussubstratetypes厚的油墨少穿過VS.噴墨或凹版印刷Thickerinkdepositsinfarfewerpassesversusinkjetorflexo/gravure製造基礎與製程知識；成熟工業Broadbaseofmanufacturersandprocessknowledge;matureindustry對新的及現有應用持續更新技術ContinuallyupdatedtechnologyfornewandcurrentapplicationsExamples:改善油墨技術(細微分散counteredbysomemeshdeflection,壓擠“Compression”,30mil,5mil,10mil,SqueegeeFace,Pressure:1.4kg/cm,在高壓下劇烈壓擠，減少全面的出墨量Severecompressionofscreenunderhighpressure,reducingoveralldeposit,成像寬度200mil以上ImageWidth5.08mmUp,總厚=紗厚膜厚只有邊緣效應及擋墨作用,總厚=紗厚+膜厚*50%,刮刀Squeegee,油墨(Ink),成像寬度1050milImageWidth0.2541.27mm,成像寬度50200milImageWidth1.255.08mm,基板Substrate,紗厚形成之印刷厚度InkDepositedbyScreen,膜厚形成之印刷厚度InkDepositedbyStencil,總厚=紗厚+膜厚,網版參數對印刷膜厚的影響,高速低壓,正確速度及印壓,慢速高壓,墨量正常,墨量過多(溢墨),刮印刀Squeegee,墨量不足,油墨Ink,網布Screen,網版膜厚Stencil,基板Substrate,S,M,P,線路(Pattern),膜厚(Stencil),網布(Mesh),W=M+S+P,L,W+P,基板(Substrate),版膜厚度效應,當線路或膜厚或網布厚度增加時會使印刷區與成像邊緣距離(W)加大,所以在選定網布時應盡量於達成所需印刷厚度之原則下,相關厚度(M,S,P)愈小愈好.,線路(Pattern),膜厚(Stencil),網布(Mesh),基板(Substrate),無法控制的流膜區(AreasofUncontrolledInkFlow),印刷時膜厚處需與基板緊密接觸才不致使油墨失控產生溢出現象.,溢墨效應,Thickness(microns),刮刀壓力SqueegeePressure(lbs/linearinch),45,35,25,20,15,.25,.50,2,4,6,8,10,40,30,刮刀壓力、膜厚與網徑Pressurevs.Thicknessvs.Linewidth,網徑Linewidth51030,Scavenging,Extruding,LowAttackAngle,Compression,(60DurometerSqueegee),膜厚,T,Mo,切變速率:,切變速率(ShearRate)R=2T*V/Mo(1/sec=sec)V:刮印刀速度.,F,切變應力:,切變應力(ShearStress)S=F/A(dyne/cm),網布Mesh,V,面積“A”Area,網布中的墨流(InkFlowWithinTheMesh),黏度V(Viscosity)液體抗拒流動的表現V=S/R(Poise)1P(Poise)=100CP(Centi-Poise),黏度與切變應力及切變速率之關係,油墨特性與印刷之關係,牛頓黏度曲線(NewtonianCurve),假性可塑曲線(PsuedoplasticCurve),牛頓流體:係指流動中能保持“切變應力/切變速率”(黏度)之比率不變者假性可塑流體:係指物質會在切變應力或切變速率增加時使黏度降低進而導致流速增加,Downstop刮刀下刀量Flood回墨ScreenReleasePeel上刀抬版SqueegeeTravel網印刮刀行程,抗垂流性(Thixotropy)又稱凝立性.在切速率不變的情況下(再限度內)凝立劑可使黏度降低,並需要一段時間以恢復到原來的黏度,此特性對高黏度油墨很重要,因為關係到印刷後油墨繼續流出時間的長短.,“假塑性”物質在切速率不變的情況下將保持相同的黏度且當應力消失的瞬間,此流質又會恢復原黏度值.,油墨與基板間各自具有“表面自由能”(Freesurfaceenergy),通常是指油墨的表面張力(SurfaceTension)及基板的臨界表面張力(CriticalSurfaceTension).其單位為:達因/公分(dyne/cm)若要使油墨能順利與基板緊密結合,油墨的表面張力需小於基板的臨界表面張力,差距愈大附著愈好(即油墨表面張力愈小),但由於油墨散佈性增加印刷之邊緣準直性較不易控制,容易產生鋸齒現象印刷物表面清潔與否關係印刷成敗致巨,必須慎重,水滴,低張力表面,高張力表面,影響印刷膜厚EffectsonThickness,Ink,刮刀硬度Durometer,刮刀角度設定AttackAngleSetting,印刷速度PrintSpeed,刮刀口角度AttackAngleatEdge,印刷壓力Pressure,刮除殘墨“Scavenging”,感光乳膠厚度EmulsionThickness,網目MeshCount,網徑WireDiameter,離版高度(網距)Snap-Off,刮刀銳利SqueegeeSharpness,網版張力MeshTension,膠黏度Viscosity,抬版ScreenPeel,最佳的實踐BestPractices(1),使用網目控制膜厚Usethescreenmeshcountastheprimarythicknesscontrol用最少感光乳劑遮蔽印刷Usetheminimumamountofemulsionbuilduptogaskettheprint選用一種刮刀硬度、形狀、角度Selectonesqueegeedurometer,shape,andangleofattack刮刀磨利及平行對基板是重要Squeegeesharpnessandparallelismtothesubstratearecritical切割適當刮刀長度及適當基板伸展Cutsqueegeetoproperlengthandoverhangofsubstrate監督網版張力的使用範圍Monitorscreentensionregularlytokeepwithinausablerange當更換網版及離版高度要監督有效印刷壓力Monitoreffectiveprintpressurewhenchangingscreensandsnap-off依據網目規格設定離版高度管制上限Setanupperlimitonsnap-offaccordingtomeshspecs維持印刷及回墨速度在嚴謹範圍Maintainprintandfloodspeedwithinatightrange(+/-2.5cm/sec),最佳的實踐BestPractices(2),絕對不使用下刀量改變印刷膜厚Neverusedownstoptocontrolorchangeprintthickness保有印刷頭的保護罩減少空氣亂流Keepaprotectivecoverovertheprintheadandreduceairturbulence監控溫濕度避免油墨問題Monitortemperatureandhumidityintheroomtopreventinkproblems執行預防維護，檢查網框及工作台Dopreventativemaintenance;checklevelofframecleanlinessisessential油墨保持瓶蓋清潔無掉落乾的油墨Keepjarmouthandlidscleanandfreeofdriedinkthatmayfallin,介電層膜厚量測DielectricThicknessMeasurement,P/D/F1,P/D/F2,R,R,M,M,1)Zero&LevelonConductor基準導電層,2)Measurewithoutincluding“humps”不含隆起,導電層ConductorPad,Microns,0,ProfilometertakesmeasurementsinthisareaonlyTotalfiredthickness=45microns,電阻層膜厚量測ResistorThick