Cov ntaub ntawv tsis muaj cov pa roj carbon monoxide yog siv dav hauv ntau lub lag luam los tsim cov ntawv luam ntawm cov ntaub ntawv tsis siv cov ntawv carbon. Qhov nrov tshaj plaws ntawm lawv yog cov ntawv tsis muaj cov ntawv dawb, uas feem ntau siv hauv cov chaw ua haujlwm tsim cov ntawv theej, daim ntawv txais nyiaj, thiab lwm yam ntaub ntawv. Txawm li cas los xij, nyob rau xyoo tas los no, cov neeg siv tau pib pom qee yam tsis pom zoo txog cov ntaub ntawv no - lawv nquag daj.
Qhov tshwm sim ntawm cov ntawv dawb carbonless tig daj tau pom los ntawm ntau tus neeg siv. Qhov kev hloov pauv tsis zoo no los ntawm dawb mus rau daj yuav zoo li tsis tseem ceeb, tab sis nws tau ua rau ntau tus neeg nug txog qhov zoo thiab ua haujlwm ntev ntawm cov ntawv tsis muaj carbon. Ua ntej peb delve rau hauv cov laj thawj vim li cas cov ntawv tsis muaj cov ntawv dawb tig daj, nws yog ib qho tseem ceeb kom nkag siab tias cov ntawv tsis muaj cov ntawv carbonless yog dab tsi.
Cov ntaub ntawv tsis muaj cov pa roj carbon monoxide, tseem hu ua "tsis muaj cov pa roj carbon yuav tsum tau" cov ntaub ntawv, yog tsim los ntawm ob peb txheej ntawm cov tshuaj tshwj xeeb thiab txheej txheej. Thaum lub siab raug siv rau cov ntawv saum toj kawg nkaus, cov tshuaj tiv thaiv los tsim cov duab theej ntawm cov txheej hauv qab. Cov txheej txheem ntawm kev hloov cov duab hauv txoj kev no tshem tawm qhov xav tau ntawm cov ntawv carbon, yog li lub npe "tsis xav tau carbon".
Tam sim no peb nkag siab txog cov ntsiab lus ntawm cov ntawv tsis muaj carbonless cia peb mus rau vim li cas lawv tig daj. Qhov tshwm sim ntawm cov ntawv tsis muaj cov ntawv dawb tig daj tsis yog tshwj xeeb rau cov ntawv tsis muaj cov ntawv ib leeg. Tag nrho cov khoom siv ntawv, tsis hais qhov zoo lossis hom, muaj peev xwm tig daj thaum lub sijhawm. Txawm li cas los xij, cov ntaub ntawv tsis muaj cov pa roj carbon monoxide tshwj xeeb yog qhov ua rau yellowing vim lawv cov khoom sib txawv.
Lub hauv paus ua rau yellowing ntawm cov ntawv tsis muaj carbonless yog kev sib xyaw ntawm ib puag ncig thiab cov tshuaj siv hauv lawv cov kev tsim kho. Kev raug rau lub teeb, cua sov, thiab noo noo tuaj yeem ua rau cov ntaub ntawv daj, raws li tuaj yeem tiv nrog cov pa phem xws li pa luam yeeb lossis cua tsis zoo. Qhov no yog qhov uas cov tshuaj nyob rau hauv cov ntawv carbonless tsim los ua si.
Cov khoom xyaw nquag hauv cov ntawv tsis muaj cov pa roj carbon monoxide feem ntau yog cov dyes thiab cov xim tsim tawm uas ua rau muaj kev hloov pauv hauv siab. Sij hawm dhau mus, cov tshuaj no tuaj yeem tawg, ua rau muaj kev hloov pauv ntawm daim ntawv xim ntawm dawb mus rau daj. Cov ntawv daj ntawm cov ntawv tsis muaj carbon kuj tuaj yeem tshwm sim vim muaj cov kua qaub nyob hauv daim ntawv pulp lossis lwm yam khoom siv hauv kev tsim khoom.
Txawm hais tias qhov tshwm sim ntawm cov ntawv tsis muaj cov ntawv dawb tig daj, lawv tseem siv dav thiab tseem yog qhov kev xaiv nrov hauv ntau qhov kev lag luam. Cov neeg tsim khoom thiab cov chaw muag khoom ntawm cov ntawv tsis muaj cov pa roj carbon monoxide tau lees paub qhov teeb meem thiab tau ua cov kauj ruam los txhim kho cov ntawv zoo kom txo qis kev pheej hmoo ntawm yellowing.
Hauv kev xaus, cov ntawv dawb carbonless yog cov khoom tseem ceeb uas tau hloov txoj kev peb tsim cov ntawv luam. Txawm hais tias lawv yuav muaj yellowing dhau lub sij hawm, qhov no yog ib qho tshwm sim uas tshwm sim nyob rau hauv tag nrho cov khoom ntawv. Qhov zoo thiab ruaj khov ntawm cov ntaub ntawv tsis muaj cov pa roj carbon monoxide tseem zoo heev, thiab nrog kev saib xyuas zoo thiab kev khaws cia, cov ntaub ntawv tuaj yeem nyob tau ntau xyoo yam tsis muaj yellowing.