Ukupakishwa okuguquguqukayoi-laminated ngamafilimu ahlukeneyo, injongo kukubonelela ngokukhuselwa kakuhle kwezinto ezingaphakathi kwimiphumo ye-oxidation, umswakama, ukukhanya, ukuvumba okanye ukudibanisa kwezi zinto.Ulwakhiwo lwezixhobo ezisetyenziswa ngokuqhelekileyo zohlulwe ngokwamaleko angaphandle, umaleko ophakathi, kunye nomaleko wangaphakathi, ii-inki kunye nezinto zokuncamathelisa.