Tsis yog Yas Coated Ntawv

Nyob rau niaj hnub no cov ntsiab lus ntawm kev paub txog ib puag ncig, cov ntawv yas tsis muaj coated, raws li hom tshiab ntawm cov khoom siv ib puag ncig, tau maj mam nyiam kev lag luam thiab nyiam. Lub hauv paus ntsiab lus tseem ceeb ntawm cov ntawv yas tsis muaj coated yog tias nws tsis siv cov txheej txheem yas, tab sis siv cov khoom siv ntuj tsim los yog cov txheej txheem ib puag ncig los xyuas kom meej tias daim ntawv tuaj yeem ua tiav cov khoom degradable thiab rov ua dua tshiab thaum tswj kev ua haujlwm zoo.