I-Waterborne (WB) UV chemistry ibonise ukukhula okukhulu ezimakethe zezinkuni zezimboni zangaphakathi ngoba ubuchwepheshe buhlinzeka ngokusebenza okuhle kakhulu, ukukhishwa okuphansi kwe-solvent kanye nokusebenza kahle kokukhiqiza okwandisiwe. Izinhlelo zokumboza i-UV zinikeza umsebenzisi wokugcina izinzuzo zokumelana okuvelele kwamakhemikhali nokuklwebheka, ukumelana okuhle kakhulu kwamabhulokhi, ama-VOC aphansi kakhulu kanye nendawo encane yokugcina imishini enesikhala esincane sokugcina esidingekayo. Lezi zinhlelo zinezakhiwo eziqhathaniswa kahle nezinhlelo ze-urethane ezinezingxenye ezimbili ngaphandle kwezinkinga ze-crosslinkers eziyingozi kanye nezinkinga zokuphila ebhodweni. Uhlelo lulonke lubiza kahle ngenxa yesivinini sokukhiqiza esengeziwe kanye nezindleko zamandla eziphansi. Lezi zinzuzo ezifanayo zingaba wusizo ezinhlelweni zangaphandle ezisetshenziswa efektri kufaka phakathi amafreyimu amafasitela neminyango, i-siding kanye neminye imisebenzi yokugaya. Lezi zingxenye zemakethe zivame ukusebenzisa ama-emulsion e-acrylic kanye ne-polyurethane dispersions ngoba anokukhanya okuhle kakhulu nokugcinwa kombala, futhi abonisa ukuqina okuphezulu. Kulesi sifundo, ama-resin e-polyurethane-acrylic anokusebenza kwe-UV ahlolwe ngokwezincazelo zemboni kokubili izinhlelo zezinkuni zezimboni zangaphakathi nangaphandle.
Izinhlobo ezintathu zezingubo ezisekelwe ku-solvent zivame ukusetshenziswa ezisetshenziswa ezinkunini zezimboni. I-Nitrocellulose lacquer ngokuvamile iyinhlanganisela ye-nitrocellulose namafutha noma ama-alkyd asekelwe ku-oyela. Lezi zingubo zoma ngokushesha futhi zinamandla okucwebezela aphezulu. Ngokuvamile zisetshenziswa ezisetshenziswa efenisha yokuhlala. Zinobunzima bokuphuzi ngokuhamba kwesikhathi futhi zingaqhekeka. Futhi zinokumelana okungekuhle kwamakhemikhali. Ama-lacquer e-Nitrocellulose anama-VOC aphezulu kakhulu, ngokuvamile angama-500 g/L noma ngaphezulu. Ama-lacquer ase-pre-catalyzed ayizingxube ze-nitrocellulose, amafutha noma ama-alkyd asekelwe ku-oyela, ama-plasticizer kanye ne-urea-formaldehyde. Asebenzisa i-catalyst ebuthakathaka njenge-butyl acid phosphate. Lezi zingubo zihlala cishe izinyanga ezine. Zisetshenziswa efenisha yasehhovisi, yesikhungo kanye neyendawo yokuhlala. Ama-lacquer ase-pre-catalyzed anokumelana okungcono kwamakhemikhali kune-nitrocellulose lacquer. Futhi anama-VOC aphezulu kakhulu. Ama-varnish okuguqulwa ayizingxube ze-alkyd asekelwe ku-oyela, i-urea formaldehyde kanye ne-melamine. Basebenzisa i-catalyst enamandla ye-asidi njenge-p-toluene sulfonic acid. Banokuphila kwebhodwe amahora angama-24 kuya kwangu-48. Basetshenziswa emakhabetheni asekhishini, ifenisha yehhovisi kanye nezicelo zefenisha yokuhlala. Ama-varnish okuguqula anezici ezinhle kakhulu zezinhlobo ezintathu zezingubo ezisekelwe ku-solvent ezivame ukusetshenziswa ngokhuni lwezimboni. Bane-VOC ephezulu kakhulu kanye nokukhishwa kwe-formaldehyde.
Ama-emulsion e-acrylic asekelwe emanzini ahlanganisa ngokwawo kanye nokuhlakazeka kwe-polyurethane kungaba izindlela ezinhle kakhulu zokusebenzisa imikhiqizo esekelwe kwi-solvent yokusetshenziswa kwezinkuni zezimboni. Ama-emulsion e-Acrylic anikeza ukumelana okuhle kakhulu kwamakhemikhali namabhulokhi, amanani obulukhuni obuphezulu, ukuqina okuvelele kanye nokubekezelela isimo sezulu, kanye nokunamathela okuthuthukisiwe ezindaweni ezingenazo izimbobo. Anezikhathi zokomisa ezisheshayo, okwenza ikhabhinethi, ifenisha noma umenzi wemikhiqizo yokwakha akwazi ukuphatha izingxenye ngokushesha ngemva kokusetshenziswa. Ama-PUD anikeza ukumelana okuhle kokuguguleka, ukuguquguquka, kanye nokumelana nokuklwebheka kanye nokonakala. Angabalingani abahle bokuxubana nama-emulsion e-acrylic ukuthuthukisa izakhiwo zemishini. Kokubili ama-emulsion e-acrylic kanye nama-PUD angasabela ngamakhemikhali ahlanganisayo njenge-polyisocyanates, i-polyaziridine noma i-carbodiimides ukuze akhe izembozo ze-2K ezinezakhiwo ezithuthukisiwe.
Izembozo ze-UV eziphathwa ngamanzi ziye zaba yizinketho ezidumile zokusetshenziswa kwezinkuni zezimboni. Abakhiqizi bamakhabethe asekhishini kanye nefenisha bakhetha lezi zembozo ngoba zinokumelana okuhle kakhulu kanye nezakhiwo zemishini, izakhiwo ezinhle kakhulu zokusetshenziswa kanye nokukhishwa kwe-solvent okuphansi kakhulu. Izembozo ze-UV ze-WB zinokumelana okuhle kakhulu kwe-block ngokushesha ngemva kokulungiswa, okuvumela izingxenye ezimboziwe ukuthi zibekwe ndawonye, zipakishwe futhi zithunyelwe ngqo emgqeni wokukhiqiza ngaphandle kwesikhathi sokuhlala isikhathi sokuthuthukiswa kokuqina. Ukuthuthukiswa kokuqina kwezembozo ze-UV ze-WB kuyamangalisa futhi kwenzeka ngemizuzwana. Ukumelana kwamakhemikhali kanye namabala kwezembozo ze-UV ze-WB kuphakeme kunokwe-varnish yokuguqulwa esekelwe ku-solvent.
Izembozo ze-WB UV zinezinzuzo eziningi ezingokwemvelo. Ngenkathi ama-oligomer e-UV aqinile angu-100% evame ukuba phezulu ku-viscosity futhi kumele ancishiswe nge-reactive diluents, ama-WB UV PUD aphansi ku-viscosity, futhi i-viscosity ingalungiswa nge-WB rheology modifiers yendabuko. Ama-WB UV PUD anesisindo esikhulu sama-molecule ekuqaleni futhi awakhi isisindo sama-molecule njengoba elapha kakhulu njengezembozo ze-UV eziqinile ezingu-100%. Ngenxa yokuthi anokuncipha okuncane noma awanciphi nhlobo njengoba elapha, ama-WB UV PUD anokunamathela okuhle kakhulu kuma-substrate amaningi. Ukukhanya kwalezi zembozo kulawulwa kalula ngama-matting agents endabuko. Lawa ma-polymer angaba nzima kakhulu kodwa futhi aguquguquke kakhulu, okwenza abe ngabantu abafanelekile bezembozo zokhuni zangaphandle.
Isikhathi sokuthunyelwe: Mashi-07-2024
