11. *** Dab tsi yog opacity ntawm daim ntawv? ***
A: Opacity hais txog qhov uas daim ntawv tiv thaiv kev sib kis ntawm lub teeb, yog li tiv thaiv qhia tawm qhia tawm. Opacity ntawm daim ntawv nyob ntawm nws lub teeb scattering muaj peev xwm, piv txwv ntawm lub teeb nrig ntawm kev sib cuam tshuam ntawm cov kev cuam tshuam loj ntawm cov kev cuam tshuam no. A higher number of light scattering interfaces, along with a greater difference in refractive indices between scattering interfaces, enhances light scattering ability and increases paper opacity.
12. *** Ua li cas ua rau ua rau muaj kev cuam tshuam rau cov opacity ntawm daim ntawv? ***
A: Daim ntawv tsis tiav muaj cov fibers thiab huab cua. Cov huab cua nyob hauv lub qhov hws ntawm cov fibers, thiab vim muaj cov khoom siv hluav taws xob txawv ntawm cov pa roj av thaum lub nqaj ntaus cov ntawv. Qhov no scattering txhawb rau daim ntawv hloov (tsawg) opacity, uas nyob rau hauv kev luam ntawv ua manifests raws li yooj yim ntawm ink nkag. Ntxiv rau cov fillers nrog qhov ntsuas qhov siab dua li ntawm cov cellulose nce ntxiv tus naj npawb ntawm lub teeb tawg hauv daim ntawv. Tshwj xeeb, peb qhov sib cuam tshuam sib cuam tshuam tau tsim: fiber ntau-cua, muab tub lim-fiber, thiab muab tub lim-huab cua. Ntawm cov no, cov kev ntsuas hluav taws xob qhov sib txawv ntawm cov muab tub lim thiab huab cua yog qhov tseem ceeb, ua rau lub teeb ci ntsa iab ntawm cov tub lim-cua interface thiab yog li txhim kho daim ntawv opacity.
13. *** Npaum li cas ua tub lim txhim kho cov ntawv saum npoo smoothness? ***
A: Lub network tsim los ntawm interwoven fibers inherently muaj ntau qhov hws thiab ua kom pom cov ntxau. Ntxiv cov fittre fittrers txhim kho cov muag muag thiab cov yas ntawm daim ntawv, ua kom muaj kev kho kom zoo dua thiab yog li kev txhim kho lub smoothness ntawm daim ntawv tom qab calendering.
14. *** Dab tsi yog qhov ua tau zoo ntawm cov tub lim rau ntawm lub zog ntawm daim ntawv? ***
A: Daim ntawv cog lus ntawm cov fibers ua lub hauv paus ntawm daim ntawv muaj zog. Ntxiv cov fitters txo cov fiber ntau-sib koom ua ke, thiab yog li, ntxiv cov tub lim dej kom ntau diminishes ntawv zog. Tshwj xeeb, tense zog, folding endurance, thiab tawg tsis kam yog txo qis dua, thaum lub noob tiv taus kom tsawg dua. Yog li ntawd, tus nqi ntawm cov lim siv yuav tsum tau ua tib zoo tswj hwm.
15. *** Cas ua tub lim rau cov tuab ntawm daim ntawv? ***
A: Ntawv fibers muaj qhov ntom ntom ntawm kwv yees li 1 g / cm³, hos feem ntau fitters muaj qhov sib txawv ntawm 2.5 rau 3.0 g / cm³. Yog li, ntxiv cov fillers txo qhov tuab tuab ntawm daim ntawv. Txawm li cas los xij, thaum tus nqi ntawm cov muab tso quav yog qhov me me, cov tuab tuab yuav nce ntxiv nrog cov tub sau ua ke, tshwj xeeb rau cov ntaub ntawv luv.
16. *** Ua li cas ua rau cov tub lim rau kev tawv ntawm daim ntawv? ***
A: Daim ntawv txhav txhav yog qhov ua haujlwm ntawm ob qho nws tuab thiab elastic modulus. Txhawm rau ntsuas qhov cuam tshuam ntawm fillers ntawm txhav, ib qho yuav tsum xav txog lawv cov kev cuam tshuam ntawm cov tuab tuab thiab lub zog tensile. Thaum tus nqi muab tub lim me me, nws ntxiv tias tsis cuam tshuam ntau daim ntawv txhav txhav. Txawm li cas los xij, raws li cov tub lim cov ncauj lus nce ntxiv, txhav txo qis zuj zus.
17. *** Lub luag haujlwm ntawm cov xim hauv ntawv yog dab tsi? ***
A: Txawm tias Bleached purp fimit Pom daj lossis xim grey vim yog lub teeb liab ntawm 400 lub teeb liab ntawm 400-500 nm. Cov ntsiab lus lignin cov ntsiab lus tshwm sim hauv daim ntawv tsaus. Yuav kom ua tiav siab dua whiteness, xiav-liabple lossis liab-xiav dyes feem ntau ntxiv rau cov tshuaj dawb. Cov ntawv xim ntau lawm kuj yuav tsum tau zas.
18. *** Yuav ua li cas cov khoom xyaw ntawm cov xim? ***
A: Colorants suav nrog pigments thiab dyes siv rau zas thiab toning ntawv. Feem ntau cov pigments yog cov tshuaj yeeb dej caw thiab insoluble hauv dej. Dyes tuaj yeem yog ntuj lossis hluavtaws; Synthetic Dyes tau hloov ntau yam thiab yog feem ntau dej-soluble los yog ua li ntawd tom qab kho tshuaj lom neeg.
19. *** Lwm yam tshuaj lom neeg tshuaj lom zem hauv cov ntawv txuas ntxiv thiab lawv cov teebmeem? ***
A: Kom tau raws li cov cai tshwj xeeb rau qee daim ntawv thov, ntau cov tsis muaj cov tsis muaj roj fiber ntxiv ua ke rau hauv pulp lossis ntawv. Cov no tuaj yeem raug faib ua hauv qab no:
(1) SIZING cov neeg sawv cev: Ntxiv nrog xws li urea-formaldehyde resin thiab Phenolic Loodin txhim kho daim ntawv sizing.
(2) Cov tshuaj tiv thaiv qhuav qhuav: cov tshuaj zoo li Cationic Starch thiab Polyacrylamide txhim kho lub zog ua kom muaj zog.
(3) Retention aids: Compounds such as polyacrylamide, polyoxyethylene, and polyvinylimidazole reduce filler and fine fiber losses during papermaking.
(4) defoamers: Cov neeg sawv cev zoo li roj silicone, turpentine, tributyl phosphate, kev haus cawv, thiab octanol tshem npaus thaum papermaking.
(5) Cov neeg sawv cev dej: cov ntaub ntawv xws li paraffin siv quav ciab, xab npum, thiab cov txiv neej ua yeeb yam, thiab dimethylams ntau ntxiv hauv cov ntaub ntawv tshwj xeeb.
20. *** Yuav ua li cas thiaj li yuav ntawv tau yooj yim cais? ***
A: Daim ntawv yog feem ntau tau cais raws li nws siv rau hauv kev siv cov ntawv kab lis kev cai, ntawv tsev, thiab ntawv tshwj xeeb. Daim ntawv kab lis kev cai tuaj yeem muab faib ntxiv rau daim ntawv tsis muaj ntaub ntawv (piv txwv li ntawv, sau daim ntawv, daim ntawv qhia hnub nyoog, iav duab qhia iav).