Cov txheej txheem tsim cov ntawv kab lis kev cai feem ntau muaj ob theem tseem ceeb: pulping thiab papermaking. Thaum cov txheej txheem tshwj xeeb sib txawv nyob ntawm seb hom ntawv kab lis kev cai (xws li ntawv coated, ntawv tsis muaj ntoo, thiab ntawv xov xwm), tag nrho cov txheej txheem zoo ib yam.
Pulping txheej txheem
Pulping yog txheej txheem ntawm kev cais cov nroj tsuag fiber ntau raw cov ntaub ntawv (xws li ntoo, xyoob, straw, thiab cov ntawv pov tseg) rau hauv fibers haum rau papermaking. Nws feem ntau suav nrog cov txheej txheem hauv qab no:
Tshuaj Pulping: Siv cov tshuaj daws teeb meem (xws li cov txheej txheem sulfate) los ua cov khoom siv raw tshem tawm cov impurities xws li lignin, khaws cov fibers ntshiab. Txoj kev no ua rau cov tawv nqaij muaj zog thiab lub teeb xim, haum rau siab - cov ntaub ntawv kab lis kev cai zoo xws li cov ntawv tsis muaj ntoo thiab cov ntawv luam tawm offset.
Mechanical Pulping: Siv lub tshuab txiav ntoo los txiav cov ntoo ncaj qha rau hauv cov fibers. Txoj kev no muaj cov txiaj ntsig siab tab sis cov fibers luv dua, thiab daim ntawv yog nquag yellowing. Nws feem ntau yog siv rau cov ntawv xov xwm thiab lwm hom ntawv uas yuav tsum tau ua kom ntev tsis siab.
Semi-chemical/chemimechanical pulp: Kev sib xyaw tshuaj pretreatment thiab mechanical refining, balancing yield and quality, it is commonly used in mid-ntau yam kab lis kev cai cov khoom xws li molded paper.
Cov ntaub ntawv siv dua tshiab: Ua los ntawm cov ntawv pov tseg los ntawm deinking, ntxuav, thiab tshuaj xyuas cov txheej txheem, nws yog ib puag ncig tus phooj ywg thiab lub zog-txuag, thiab siv dav hauv kev tsim cov ntaub ntawv kab lis kev cai.
Papermaking txheej txheem
Papermaking yog txheej txheem ntawm kev sib cais ntawm cov ntaub so ntswg hauv dej thiab tom qab ntawd tsim cov ntawv tiav los ntawm cov kauj ruam xws li kev tsim, dewatering, nias, ziab, txheej, thiab calendering. Cov txheej txheem tseem ceeb yog raws li nram no:
Pulp Mixing and Preparation: Pulps from different sources are mixed in proportions, and fillers (xws li calcium carbonate thiab titanium dioxide), sizing agents (kom txhim kho dej tsis kam), dyes, thiab lwm yam additives yog ntxiv kom tau raws li qhov yuav tsum tau ua ntawm cov ntawv tshwj xeeb.
Paper forming (Forming): Tom qab dilution, lub pulp yog pub rau hauv seem hlau ntawm lub tshuab ntawv, qhov twg dej yog lim los ntawm ib tug siab - ceev hlau screen, thiab fibers yog uniformly tso rau hauv daim ntawv ntub daim ntawv. Qhov no yog ib kauj ruam tseem ceeb los txiav txim siab qhov sib xws thiab smoothness ntawm daim ntawv.
Nias thiab Dewatering: Daim ntawv ntub dej hla dhau los ntawm ntau lub siab chais kom ntxiv nyem tawm cov dej noo, txhim kho daim ntawv qhuav thiab lub zog.
Kev ziab: Cov ntawv ntawv nkag mus rau lub tog raj kheej kom qhuav, qhov chaw cua sov ua kom cov dej noo mus rau cov ntsiab lus noo noo (feem ntau qis dua 6%), ua kom cov ntawv ruaj khov thiab luam tawm.
Kev kho deg (nyob ntawm hom ntawv)
Txheej: Siv rau cov ntawv coated, lub teeb yuag coated ntawv, thiab lwm yam., qhov no yuav tsum txheej cov ntawv nto nrog kaolin, latex, los yog lwm yam coatings los txhim kho gloss, smoothness, thiab print clarity. Raws li tus nqi txheej, nws tuaj yeem raug cais raws li super, hwm, lossis cov ntawv coated tsis tu ncua.
Daim ntawv qhia hnub: Daim ntawv yog nias siv cov menyuam kub thiab txias los txhim kho qhov gloss thiab smoothness. Feem ntau siv rau woodfree ntawv, offset ntawv, thiab lwm yam.
Rolling thiab Slitting: Cov ntawv tiav yog dov rau hauv cov yob loj, tom qab ntawd txiav rau hauv cov ntawv los yog cov yob me me raws li kev lag luam xav tau, thiab ntim rau cov khoom xa tuaj.
