Cov khoom dawb feem ntau me ntsis nqus lub teeb xiav (450-480nm) hauv qhov pom kev pom (yav dav dav 400-800nm), ua rau cov xim xiav tsis txaus, ua rau nws daj me ntsis, thiab ua rau tib neeg muaj kev xav ntawm cov laus thiab tsis huv vim qhov cuam tshuam dawb.Txog rau qhov kawg no, tib neeg tau siv cov kev ntsuas sib txawv los ua kom cov khoom zoo nkauj thiab ci ntsa iab.
Muaj ob txoj hauv kev uas feem ntau siv, ib qho yog Garland whitening, uas yog, ntxiv ib qho me me ntawm cov xim xiav (xws li ultramarine) rau cov khoom ua ntej ci, npog cov xim daj ntawm cov substrate los ntawm kev ua kom qhov kev xav ntawm lub teeb xiav. , ua kom nws tshwm dawb.Txawm hais tias garland tuaj yeem whiten, ib qho yog txwv, thiab lwm qhov yog vim qhov txo qis ntawm tag nrho cov teeb pom kev zoo, qhov ci ntsa iab raug txo, thiab xim ntawm cov khoom yuav tsaus dua.Lwm txoj kev yog tshuaj bleaching, uas fades cov xim los ntawm redox cov tshuaj tiv thaiv nyob rau saum npoo ntawm cov khoom nrog pigment, yog li nws yuav inevitably ua puas lub cellulose, thiab cov khoom tom qab bleaching muaj lub taub hau daj, uas cuam tshuam rau kev pom kev.Fluorescent whitening agents pom nyob rau xyoo 1920s tau tsim los rau qhov tsis zoo ntawm cov txheej txheem saum toj no thiab pom qhov zoo sib xws.
Fluorescent whitening agent yog ib qho organic compound uas tuaj yeem nqus tau ultraviolet lub teeb thiab ua kom muaj xim xiav lossis xiav-violet fluorescence.Cov tshuaj nrog fluorescent whitening tus neeg sawv cev adsorbed tuaj yeem cuam tshuam lub teeb pom kev irradiated ntawm cov khoom, thiab tseem Lub teeb pom kev pom tsis pom ultraviolet (wavelength yog 300-400nm) hloov mus rau xiav lossis xiav-violet pom lub teeb thiab tawm, thiab xiav thiab daj yog cov xim ntxiv. rau ib leeg, yog li tshem tawm cov daj nyob rau hauv matrix ntawm tsab xov xwm, ua kom dawb thiab zoo nkauj.Ntawm qhov tod tes, qhov emissivity ntawm cov khoom mus rau lub teeb yog nce, thiab qhov kev siv ntawm lub teeb emitted tshaj qhov siv ntawm thawj pom lub teeb projected ntawm cov khoom yuav tsum tau ua.Yog li ntawd, qhov whiteness ntawm cov khoom pom los ntawm tib neeg lub qhov muag nce, yog li ua tiav lub hom phiaj ntawm whitening.
Fluorescent whitening agents yog ib chav kawm ntawm cov organic tebchaw nrog cov qauv tshwj xeeb uas muaj kev sib txuas ntawm ob daim ntawv cog lus thiab zoo planarity.Nyob rau hauv tshav ntuj, nws muaj peev xwm nqus tau ultraviolet rays uas tsis pom ntawm qhov muag liab qab (wavelength yog 300 ~ 400nm), excite molecules, thiab ces rov qab mus rau hauv av xeev, ib feem ntawm lub zog ultraviolet yuav ploj mus, thiab ces hloov mus rau hauv xiav-violet lub teeb. nrog qis zog (wavelength 420 ~ 480nm) tawm.Nyob rau hauv txoj kev no, qhov kev xav ntawm lub teeb xiav-violet ntawm lub substrate tuaj yeem nce ntxiv, yog li offsetting lub siab daj tshwm sim los ntawm qhov loj ntawm lub teeb daj los ntawm cov khoom qub, thiab pom qhov ua rau muaj xim dawb thiab dazzling.
Kev ua kom dawb ntawm fluorescent whitening tus neeg sawv cev tsuas yog kev ua kom pom tseeb thiab ua kom muaj xim ntxiv, thiab tsis tuaj yeem hloov cov tshuaj bleaching kom muab cov ntaub tiag tiag "dawb".Yog li ntawd, yog tias cov ntaub nrog cov xim tsaus yog kho nrog fluorescent whitening tus neeg sawv cev ib leeg yam tsis muaj tshuaj bleaching, qhov txaus siab dawb tsis tuaj yeem tau txais.Cov tshuaj bleaching dav dav yog cov muaj zog oxidant.Tom qab cov fiber ntau yog bleached, nws cov ntaub so ntswg yuav raug puas ntsoog rau ib tug tej yam, thaum lub whitening nyhuv ntawm fluorescent whitening tus neeg saib xyuas yog ib tug kho qhov muag nyhuv, yog li ntawd nws yuav tsis ua puas rau cov ntaub so ntswg fiber.Ntxiv mus, tus neeg sawv cev fluorescent whitening muaj xim mos thiab dazzling fluorescent xim nyob rau hauv tshav ntuj, thiab vim hais tias tsis muaj ultraviolet lub teeb nyob rau hauv lub teeb incandescent, nws tsis zoo li dawb thiab dazzling li nyob rau hauv tshav ntuj.Lub teeb nrawm ntawm fluorescent whitening agents txawv rau ntau yam sib txawv, vim hais tias nyob rau hauv qhov kev txiav txim ntawm ultraviolet lub teeb, cov molecules ntawm whitening agent yuav maj mam puas.Yog li ntawd, cov khoom kho nrog cov tshuaj fluorescent whitening cov neeg ua haujlwm yuav txo qis hauv cov xim dawb tom qab raug tshav ntuj ntev.Feem ntau hais lus, lub teeb nrawm ntawm polyester brightener yog qhov zoo dua, cov nylon thiab acrylic yog nruab nrab, thiab cov ntaub plaub thiab lo lo ntxhuav yog qis dua.
Lub teeb nrawm thiab cov nyhuv fluorescent nyob ntawm seb cov qauv molecular ntawm fluorescent whitening tus neeg sawv cev, nrog rau qhov xwm thiab txoj hauj lwm ntawm cov khoom hloov, xws li kev taw qhia ntawm N, O, thiab hydroxyl, amino, alkyl, thiab alkoxy pawg hauv heterocyclic compounds. , uas yuav pab tau.Nws yog siv los txhim kho cov nyhuv fluorescence, thaum pab pawg nitro thiab pab pawg azo txo lossis tshem tawm cov nyhuv fluorescence thiab txhim kho lub teeb nrawm.
Post lub sij hawm: Jan-14-2022