Qhov kev txiav txim siab los nqis peev hauv flexographic xovxwm tsis tshua muaj tsav los ntawm ib hom substrate. Cov tshuab luam ntawv hloov pauv uas ua rau cov lag luam ntim tau yooj yim paub tias lub xovxwm zaum tsis ua haujlwm vim tias nws tsis tuaj yeem tuav qhov kev txiav txim tuaj yog peev uas tsis tau txais nws khaws cia. Lo lus nug tsis yog seb lub tshuab puas tuaj yeem luam tawm ntawm ib qho khoom siv - nws puas tuaj yeem hloov pauv ntawm cov ntaub ntawv yam tsis muaj sijhawm poob ntau dhau, seem, lossis kev cuam tshuam zoo.
A Kev kub ceev rau xim Flexo tshuab luam ntawvzaum hauv nruab nrab ntawm cov khoom siv spectrum: muaj peev xwm ntau dua li plaub- xim nqaim- lub vev xaib tab sis tsawg dua tshwj xeeb tshaj li yim- lossis kaum-xim nruab nrab- impress (CI) nruas configuration tsim tshwj xeeb rau kev ua haujlwm siab - kawg zaj duab xis. Nkag siab tias lub tshuab no tuaj yeem ua haujlwm li cas- thiab qhov twg nws cov ciam teb nyob - yuav tsum tau saib ntawm kev sib cuam tshuam ntawm kev tsim kho tshuab, cov khoom siv, thiab cov txheej txheem tsis ua haujlwm.
Central Impression Architecture
Feem ntau siab -ceev rau - xim presses siv lub hauv paus impression (CI) lub tog raj kheej tsim. Hauv qhov kev teeb tsa no, tag nrho rau lub chaw luam ntawv tau teeb tsa radially nyob ib ncig ntawm - txoj kab uas hla ntau lub tog raj kheej. Lub vev xaib qhwv ib ncig ntawm lub tog raj kheej no thaum nws hla txhua qhov chaw nres tsheb, uas txhais tau hais tias lub substrate tau txais kev txhawb nqa los ntawm CI nruas ntawm txhua qhov chaw uas tus number case raug xa mus.
Qhov no architecture tseem ceeb heev rau substrate versatility. Ib pawg- hom xovxwm (qhov chaw nres tsheb sib tshooj ntsug saum toj ib leeg) cuam tshuam lub vev xaib kom nrawm nrawm thaum nws nce mus los ntawm ntau lub nips. Nyias films stretch. Cov ntawv me me wrinkle. Ib qho CI xovxwm, los ntawm qhov sib piv, ua rau lub vev xaib nyob rau hauv qhov kev sib zog ruaj khov vim tias txoj kev ntev ntawm cov chaw nres tsheb luv luv thiab CI lub tog raj kheej muab kev txhawb nqa txuas ntxiv.
Kev tshawb fawb luam tawm nyob rau hauv Polymer Engineering & Science tau tshuaj xyuas qhov web tension cwj pwm nyob rau hauv ntau - chaw nres tsheb yob- mus rau - yob tshuab, ua kom pom tias CI configurations qhia qis dua kev hloov pauv ntau dua li pawg lossis hauv - kab qauv tsim thaum khiav cov txheej txheem txuas ntxiv. Qhov no yog vim li cas CI nruas presses feem ntau suav hais tias yog qhov kev xaiv zoo tshaj plaws rau kev sib xyaw ua ke - substrate ntau lawm ib puag ncig.
Substrate tuav: Dab tsi mus rau hauv lub tshuab
Daim ntawv -Based Webs
Daim ntawv thiab daim ntawv sau npe sawv cev rau kev nkag - qib substrate qeb rau feem ntau cov haujlwm flexo. Cov ntawv xov xwm, kraft liner, corrugating nruab nrab, khoom bleached sulfate board, thiab coated folding boxboard tag nrho dhau los ntawm flexo presses txhua hnub.
Dab tsi ua rau daim ntawv tswj tau los ntawm cov khoom siv pom yog nws qhov kev ruaj ntseg. Daim ntawv tsis elongate ho nyob rau hauv ib txwm nruj nreem, yog li sau npe tswj nyob rau hauv rau xim yog mechanically straightforward. Qhov kev sib tw nyob rau lwm qhov - nyob rau hauv lub zog nto thiab absorbency. Tsawg-pab- cov ntaub ntawv hnyav tuaj yeem lint thaum lub sij hawm sib cuag nrog phaj, tso cov fibers rau ntawm phaj uas ua rau cov kev xav tom ntej. TAPPI T 499 (cov khoom siv khib nyiab pov tseg) thiab TAPPI T 456 (kev ntsuas qhov du) muab cov qauv txheej txheem los ntsuas seb cov ntawv qib twg yuav muaj sia nyob flexographic kev sib cuag tsis muaj degradation.
Board qib saum toj no kwv yees li 400 gsm qhia qhov tawv nqaij-txog teeb meem. Lub rooj tsavxwm tuab tsis ua raws li yooj yim rau qhov curvature ntawm CI lub tog raj kheej, uas tsim tsis sib xws nip siab thoob plaws lub vev xaib dav. Qee cov xovxwm suav nrog segmented impression lub tog raj kheej nrog cov khoom kho kom haum rau cov nyhuv no; lwm tus cia siab rau cov pam vov npog rau ntawm lub tog raj kheej lub tswv yim kom faib cov siab sib npaug ntawm cov txheej tuab tuab.
Polyolefin zaj duab xis
Biaxially oriented polypropylene (BOPP), low- ntom polyethylene (LDPE), linear low-density polyethylene (LLDPE), thiab cam khwb cia polypropylene (CPP) ua ke suav nrog rau feem ntau ntawm cov khoom ntim tau yooj yim ntim cov ntawv luam tawm thoob ntiaj teb.
Cov yeeb yaj kiab no nthuav tawm cov teeb meem sib txawv dua li ntawv. Lawv muaj lub zog qis dua, txhais tau tias tus number case yuav tsis ntub lawv tshwj tsis yog tias qhov chaw tau kho. Lawv kuj tseem kub dua -rhiab heev: BOPP zaj duab xis pib ntsws yog tias lub qhov ziab qhuav tshaj li ntawm 120-130℃, thiab PE zaj duab xis soften txawm tias qis dua.
Yog li kev kho saum npoo yog tsis yog -negotiable. Corona tso tawm units tau teeb tsa hauv kab ua ntej thawj qhov chaw luam ntawv ionize cov zaj duab xis saum npoo, tsim cov pawg polar uas nce lub zog saum npoo los ntawm ib ncig ntawm 30 dynes/cm mus rau 38-42 dynes/cm-qhov ntau ntawm cov dej-raws li lossis hnyav-raws li flexo inks ua tiav cov ntaub ntub dej txaus thiab adhesion. ASTM D2578 qhia txog dyne cwj mem xeem txoj kev siv los txheeb xyuas qib kev kho mob ua ntej luam ntawv tiav.
Rau cov converters uas khiav ob daim ntawv thiab zaj duab xis ntawm tib kab, ib tug High Speed Six Xim Flexo Printing Tshuab nruab nrog ib tug xaiv corona chaw nres tsheb uas yuav tsum tau koom los yog disengaged nyob ntawm seb lub substrate muaj kev ua hauj lwm yooj yooj yim. Yog tsis muaj lub peev xwm no, hloov ntawm cov ntawv tsis kho kraft (uas yuav tsum tsis muaj corona) thiab tsis kho BOPP (uas xav tau) yuav xav tau ua ntej - kho cov yeeb yaj kiab offline lossis lees txais cov txiaj ntsig tsis sib xws.
Polyester thiab Barrier Films
Polyethylene terephthalate (PET) thiab polyamide (PA, nylon) cov yeeb yaj kiab tuav qhov siab dua - kev ua tau zoo kawg ntawm kev lag luam ntim khoom lag luam. PET yog qhov ruaj khov, tiv taus kev ncab, thiab ua rau kom qhuav kub dua li polyolefins. Nws yog, nyob rau hauv ntau yam, yooj yim rau khiav ntawm kev kub ceev ntawm flexo xovxwm tshaj BOPP lossis PE.
Nylon films qhia hygroscopic rhiab heev. Nylon absorbs ambient noo noo, thiab qhov nqus tau hloov nws qhov ntev. Lub vev xaib nylon uas tau sau npe kom zoo thaum pib ntawm kev hloov pauv tuaj yeem tawm ntawm kev sau npe raws li cov av noo hloov mus rau hnub. Cov xovxwm tau teeb tsa rau cov khoom siv nylon tsis tu ncua feem ntau suav nrog kev tswj hwm ib puag ncig ib puag ncig ntawm lub vev xaib thiab tuaj yeem siv servo-tsav kev them nyiaj rau cov menyuam uas kho lub vev xaib ntev dynamically raws li cov lus pom zoo.
Barrier films uas muaj ethylene vinyl cawv (EVOH) los yog txhuas metallization txheej yuav tsum tau xyuam xim rau qhov tseeb hais tias lub barrier txheej nws tus kheej yuav raug puas los ntawm ntau nip siab los yog hnyav raug. Thaum lub tshuab luam ntawv tsis ncaj qha kuaj cov khoom thaiv tom qab luam ntawv, tus neeg teb xov tooj yuav tsum paub tias kev luam ntawv hnyav tuaj yeem cuam tshuam cov pa xa hluav taws xob ntsuas raws li ASTM F1927 tus qauv.
Aluminium Ntawv Nyiaj
Aluminium ntawv nyiaj-feem ntau yog 6 txog 15 microns tuab- yog khiav ntawm flexo presses feem ntau rau kev ntim tshuaj thiab khoom noj khoom haus zoo tshaj. Cov ntawv ci tsis yog - ntxeem tau, tsis yog - nqus, thiab qhov ntev. Ink dries tag nrho los ntawm evaporation es tsis yog nkag mus.
Qhov tseem ceeb ntawm kev ua haujlwm nrog cov ntawv ci yog kev huv. Kev tsim cov ntawv ci tawm cov kua nplaum uas seem thiab cov tshuaj tiv thaiv - zoo li qub rau ntawm qhov chaw. Yog tias cov kab mob no nyob twj ywm, lawv cuam tshuam nrog cov kua nplaum ntub dej. Inline corona los yog nplaim taws kho tam sim ntawd ua ntej thawj xim chaw nres tsheb yog cov qauv kev coj ua. Kev kho nplaim hluav taws yog qhov tshwj xeeb tshaj yog rau cov ntawv ci vim nws ib txhij ntxuav cov organic residues thiab oxidizes hlau nto.
Cov ntawv ci kuj yuav tsum tau ceev faj tuav hauv cov ntu thiab rov qab. Vim tias cov kua muag foil ntau dua li stretches, cov txheej txheem rov qab los ntawm lub vev xaib yuav tsum maj mam dua cov uas siv rau zaj duab xis. Ntau tus neeg tsav tsheb teeb tsa kev nrawm nrawm dua thiab txo qhov siab tshaj plaws kev txwv thaum hloov los ntawm zaj duab xis mus rau cov ntawv ci khiav ntawm tib lub tshuab.
Nonwoven Npuag
Spunbond thiab meltblown polypropylene nonwovens tau dhau los ua thaj chaw loj hlob rau flexo luam ntawv, tsav los ntawm kev thov rau cov khoom ntim tshuaj kho mob thiab cov hnab ntim khoom siv rov siv tau. Nonwovens coj txawv ntawm lwm yam flexo substrate. Lawv compressed nyob rau hauv nip siab, rov qab ib nrab tom qab dhau los ntawm lub tswv yim, thiab haus ntau npaum li tus number case ntau tshaj qhov sib npaug - cheeb tsam zaj duab xis los yog ntawv vim tus number case nkag mus rau hauv cov fiber ntau ntau dua li nyob rau saum npoo.
Sau npe tswj ntawm nonwovens yog qhov nyuaj heev. Kev tshawb fawb rau hauv web tuav ntawm cov ntaub ntawv uas tsis yog-woven hauv yob-rau- yob cov txheej txheem, sau tseg hauv cov txheej txheem txheej txheem ntawm TAPPI thiab AIMCAL cov koom haum, pom zoo kom nthuav dav cov kab ntawv luam tawm thiab cov ntsiab lus tsis txaus siab thaum luam tawm ntawm cov ntaub ntawv tsis yog piv rau cov yeeb yaj kiab lossis cov ntawv. Ib tug rau -xim flexo xovxwm khiav cov ntaub ntawv tsis-woven feem ntau ua haujlwm ntawm kev txo qis-feem ntau 40–60% ntawm qhov ntsuas siab tshaj plaws -kom tswj tau qhov kev tso npe raug.
Ink System Kev txiav txim siab thoob plaws substrates
Kev xaiv ntawm cov kuab tshuaj-raws li, dej-raws li, thiab UV- inks curable yog sib cais los ntawm cov lus nug hauv substrate.
Cov kuab tshuaj-raws li cov inks qhuav sai thiab zoo li ci ntsa iab ntawm qhov tsis yog - ntxeem tau zoo li zaj duab xis thiab ntawv ci. Tab sis lawv xav tau cov kuab tshuaj rov qab los yog tshem tawm cov txheej txheem hauv ntau qhov chaw vim yog VOC cov cai emission. Cov kev cai no suav nrog EPA's Clean Air Act thiab European Union's Industrial Emissions Directive (IED). Cov tshuab tuaj yeem yog cov khoom siv thermal oxidizers lossis carbon adsorption units. Yog li rau lub tshuab uas yuav tsum ua haujlwm ntawm ntau yam khoom sib txawv, cov kuab tshuaj hnyav tuaj yeem ua haujlwm ntawm yuav luag txhua yam ntawm lawv. Tab sis lawv kuj ntxiv ua haujlwm ntxiv kom ua raws li cov cai.
Dej-raws li inks yog qhov tseem ceeb, tshwj xeeb tshaj yog nyob rau hauv cheeb tsam uas nruj VOC cov cai. Lawv qhuav zoo rau ntawm qhov ntxeem tau substrate (daim ntawv, board) thiab txaus ntawm cov yeeb yaj kiab kho. Lawv qhov kev txwv yog ceev: cov dej evaporates qeeb dua li cov kuab tshuaj organic, uas tuaj yeem txwv kev tsim tawm ntawm cov khoom tsis yog- ntxeem tau substrates tshwj tsis yog ncua kev ziab qhov tob lossis siab dua- cua kub riam raug teeb tsa.
UV inks kho tam sim ntawd thaum raug ultraviolet teeb. Lawv tsis qhuav los ntawm evaporation tag nrho -lawv polymerize. Qhov no txhais tau tias UV inks zaum ntawm lub substrate nto raws nraim li tso, muab tshwj xeeb dot sharpness thiab tsis kam mus abrasion. Tsis yog txhua lub substrates txais UV inks sib npaug. Cov ntaub ntawv uas nqus tau siab heev tuaj yeem nqus tau qhov qis -viscosity UV number case lub tsheb ua ntej kev kho, ua rau cov kua nplaum tsis zoo. Qee cov yeeb yaj kiab yas muaj cov khoom siv ntxiv (UV stabilizers, cov neeg ua haujlwm plam) uas txav mus rau saum npoo thiab cuam tshuam nrog UV kho chemistry. ASTM F1942 muab kev taw qhia ntawm UV curable number case kev ntsuas kev ua tau zoo ntawm cov substrates hloov tau.
Anilox Roll Xaiv thiab Substrate Matching
Anilox rolls txiav txim siab npaum li cas tus number case kis mus rau lub phaj thiab thaum kawg mus rau substrate. Cell ntim (tshwj xeeb hauv billion cubic micrometers ib square inch, BCM) thiab kev txiav txim tshuaj ntsuam (kab ib nti, LPI) yog ob lub ntsiab lus tshwj xeeb.
Siab dua BCM anilox rolls hloov ntau tus cwj mem, ua kom hnyav dua qhov tsim nyog rau opaque dawb keeb kwm yav dhau los yog xim xim. Qis BCM rolls tsim cov yeeb yaj kiab thinner tsim nyog rau kev ua haujlwm zoo ib nrab thiab cov txheej txheem xim luam tawm. Kev sib raug zoo ntawm kev xaiv anilox thiab substrate yog ncaj qha: cov ntaub ntawv nqus tau tuaj yeem ua kom haum cov number case ntau dua vim qee tus number case nkag mus rau hauv daim ntawv. Cov yeeb yaj kiab yuav tsum tau nruj dua tus number case tswj vim tias cov kua dej ntau dhau ntawm qhov chaw thiab tsis kho lossis qhuav nyob rau lub sijhawm nyob hauv qhov av.
Thaum lub High Speed Six Colour Flexo Printing Tshuab tau teeb tsa rau lub substrate tshiab, anilox yob xaiv feem ntau yog thawj qhov ntsuas tom qab phaj mounting. Cov neeg ua haujlwm muaj peev xwm tswj hwm cov khoom lag luam anilox uas npog ntau yam ntawm LPI / BCM kev sib xyaw ua ke thiab sib xyaw ua ke rau hom substrate siv cov ntaub ntawv pov thawj pom tau los ntawm cov haujlwm dhau los. Tam sim no tsis muaj cov qauv kev kwv yees thoob ntiaj teb uas muaj kev ntseeg siab txuas rau anilox geometry los luam tawm cov txiaj ntsig thoob plaws txhua lub substrate- ink ua ke, txawm hais tias kev tshawb fawb luam tawm hauv Kev Txhim Kho hauv Organic Coatings tau dhau los theoretical moj khaum rau cov lej hloov tshuab hauv gravure thiab flexographic systems.
Qhuav qhov Configuration
Lub tshuab ziab khaub ncaws yog arguably ib qho tseem ceeb tshaj plaws subsystem rau kev txiav txim siab dab tsi substrates ib tug muab xovxwm tuaj yeem tswj tau ntawm kev lag luam nrawm.
Kub- cua qhuav qhov yog qhov kev teeb tsa hauv qab. Cov cua kub yog qhia rau hauv lub vev xaib tshiab uas luam tawm ntawm nozzle arrays nyob nruab nrab ntawm cov chaw luam ntawv. Huab cua kub, tshaj tawm, thiab cov av noo tswj sib txawv ntawm cov tshuab. Nkag mus- qib xovxwm tuaj yeem muab cov kev ruaj khov- nrawm nrawm thiab yooj yim tswj qhov kub thiab txias. Siab dua -cov tshuab tshwj xeeb tshwj xeeb muaj qhov sib txawv- zaus tsav ntawm lub tshuab cua tshuab, thaj chaw- tswj cov cua sov, thiab cov pa tawm ntawm cov av noo sensors uas hloov pauv huab cua los tiv thaiv condensation hauv lub qhov.
