Hauv kev tshawb fawb txog xim thiab kev lag luam, qhov laj thawj yog vim li cas dyes thiab pigments tuaj yeem muab cov xim zoo nkauj rau ntau cov ntaub ntawv nyob hauv lawv cov txheej txheem physicochemical tshwj xeeb.Txawm hais tias ob qho tib si tsom rau "xim kev loj hlob," lawv cia siab rau txoj hauv kev sib txawv los tsim cov xim sib txawv.
Lub solubility ntawm dyes txiav txim siab tias lawv cov txheej txheem ntawm kev ua yog nyob rau hauv molecular - theem kev sib cuam tshuam. Dye molecules muaj chromophores xws li conjugated ob daim ntawv cog lus thiab cov nplhaib uas muaj ntxhiab, uas tuaj yeem nqus cov wavelengths tshwj xeeb ntawm lub teeb pom kev thiab cuam tshuam lwm cov wavelengths, yog li nthuav tawm xim. Thaum cov dyes tuaj rau hauv kev sib cuag nrog lub wettable matrix (xws li paj rwb fibers, txhob lo lo ntxhuav, los yog ntawv), nrog kev pab los ntawm dej los yog lwm yam kuab tshuaj, cov molecules diffuse mus rau hauv lub matrix thiab khi rau lub matrix nto pawg los ntawm covalent bonds, ionic bonds, los yog hydrogen bonds, ua tiav fixation ruaj khov. Piv txwv li, reactive dyes tsim covalent bonds nrog cellulose fibers nyob rau hauv alkaline tej yam kev mob; acidic dyes khi rau cov protein fibers los ntawm electrostatic attraction. Cov txheej txheem ntawm kev nkag mus rau molecular thiab kev sib txuas ua ke muab cov xim pleev xim zoo nkauj thiab sib xws, tab sis kuj tseem muaj qhov xav tau siab ntawm qhov sib xws ntawm qhov nruab nrab thiab cov txheej txheem. Lub insolubility ntawm pigments dictates tias lawv cov xim kev loj hlob nyob rau hauv lub cev kev sib cuam tshuam ntawm hais nrog lub teeb. Pigments yog dispersed nyob rau hauv resin, hnyav, los yog polymer matrices raws li cov khoom zoo heev. Thaum lub teeb ci rau lawv, tawg thiab xaiv qhov nqus tau tshwm sim rau ntawm qhov chaw; lub teeb unabsorbed yog perceived li xim los ntawm tib neeg lub qhov muag. Vim tias cov pigments tsuas yog nyob rau saum npoo ntawm matrix thiab tsis nkag mus rau sab hauv, lawv muaj qhov zoo tshaj plaws zais lub zog thiab kev tsiv teb tsaws chaw, ua rau lawv tsim nyog rau cov ntawv thov uas yuav tsum tau ua siab ntev rau kev sib txhuam, lub teeb raug, thiab huab cua. Inorganic pigments feem ntau cia siab rau cov qauv siv lead ua ruaj khov thiab cov tshuaj lom neeg tsis muaj zog kom ua tiav ntev; organic pigments ua tiav cov xim spectral ceev los ntawm cov chromophores conjugated heev, tab sis feem ntau xav tau kev kho saum npoo los txhim kho kev sib cais thiab huab cua tsis kam.
Feem ntau, cov xim kev loj hlob ntawm dyes yog los ntawm molecular - theem soluble binding thiab lub teeb haum, thaum cov xim kev loj hlob ntawm pigments yog dominated los ntawm lub teeb tawg thiab nqus ntawm insoluble hais. Kev nkag siab txog qhov sib txawv ntawm lawv cov hauv paus ntsiab lus pab hauv kev tshawb fawb ntawm cov ntaub ntawv thiab kev ua kom zoo ntawm cov txheej txheem hauv cov ntawv thov sib txawv, yog li ua tiav cov xim zoo nkauj thiab ruaj khov thiab tso lub hauv paus theoretical rau kev txhim kho ntsuab thiab xim xim technologies.