I-arhente yokususa igesi yiarhente encedisayo ekhupha izinto eziguquguqukayo ezifana nomoya, ukufuma, kunye neekhompawundi ezincinci zemolekyuli eziveliswa ngexesha lokudibana kunye nokuqina kweengubo zomgubo xa zinyibilika kwaye zenze ifilimu. Ikwalungisa iimbobo zemibhobho yeekhompawundi ezincinci zemolekyuli ezikhutshiweyo ngexesha elifanelekileyo, ithintela ukwenzeka kwemingxunya emincinci okanye iimbobo kwifilimu yokugcoba. Olu hlobo lokongeza lolunye lwezongezo eziqhelekileyo kwiingubo zomgubo, kwaye ludla ngokufakwa kwiifomyula zokugcoba umgubo.
I-arhente yokususa igesi esetyenziswa kakhulu kwiingubo zomgubo yi-benzoin. I-Benzoin yikristale emhlophe okanye etyheli ekhanyayo engenavumba eneqondo lokunyibilika le-133-137 ℃ kunye neqondo lokubila le-344 ℃. Inyibilika kancinci emanzini nakwi-ether, kwaye inyibilika kwi-acetone eshushu kunye ne-ethanol; Ingxaki yayo kukuba inokubangela ukutyheli kwengubo ngokulula xa kushushu. Ukuze koyiswe iingxaki ze-benzoin,ii-arhente zokususa igesi eziguqulweyo ze-benzoin kunye ne-waxziye zaphuhliswa ezingakwaziyo ukuba tyheli phantsi kweemeko zokubhaka nokuphola.
Iziphumo zovavanyo kunye neendlela zokuvelisa zibonisa ukuba ngexesha lenkqubo yokudibanisa kunye nokunyanga ii-powder coating, iintlobo zokugquma ezivelisa ii-molecule ezincinci zifuna ukongezwa kwee-degassing agents. Kusengqiqweni ukongeza i-degassing agent kwi-epoxy, epoxy polyester, polyester, kunye ne-polyurethane powder coatings kuba ii-powder coatings zineengxaki ezifana nokufunxwa lula komswakama ngexesha lokuveliswa nokusetyenziswa. Kwi-epoxy matte kunye ne-matte powder coatings, akulula ukuvelisa ii-pinholes kunye nezinye iziphene ngaphandle kokongeza ii-defoamers ezifana ne-benzoin. Isizathu asinakuchazwa ngokucacileyo okwangoku, kwaye kusenokwenzeka ukuba umphezulu we-coating awugudi kwaye ucwebezela njenge-gloss ephezulu, kwaye ezinye iziphene zokugquma azibonakali, nto leyo ebangela imvakalelo.
Okwangoku, i-benzoin iseyiarhente yokususa igesi esetyenziswa kakhulu, inomlinganiselo omalunga ne-0.5% yezinto ezibumba ifilimu kwiingubo zomgubo, onokulungiswa ngokufanelekileyo ngaphakathi koluhlu oluthile ngokweentlobo ngeentlobo kunye nokwakheka kweengubo zomgubo. Kwiingubo zomgubo ze-polyester-HAA (hydroxyalkylamide), xa kujongwa impembelelo ye-benzoin ekutyhelini kwefilimu yokugquma, umthamo wayo kufuneka ulawulwe malunga ne-0.3% yenani lilonke lezinto ezibumba ifilimu, kwaye ukusetyenziswa kufuneka kuncitshiswe kangangoko kunokwenzeka.Ukongeza, izinto zokuthambisa nezokukhupha igesi ezisekelwe kwi-wax yokwenziwa nazo zingasetyenziswa, kunye nomthamo omalunga ne-1% yefomyula iyonke yokugquma umgubo.
Kwimixube yokugquma ngomgubo, ii-defoamers zongezwa kwisinyithi esityhidiweyo, kwi-aluminium etyhidiweyo, kwiipleyiti zentsimbi ezigqunyiweyo ezishushu, nakwiipleyiti zentsimbi eziqengqelekayo ezishushu ezinemingxuma yesanti okanye imingxuma ephezu kwento egqunyiweyo (into yokusebenza) ngexesha lokugquma ngomgubo ukuthintela ukwakheka kwamasuntswana okanye imingxunya yentaba-mlilo kwifilimu yokugquma. Zizongezo ezongeziweyo ukuthintela ukwakheka kwamaqamza kwifilimu yokugquma.
Xa kufakwa i-powder coating kwiindawo zesinyithi eziphosiweyo, kwiindawo ze-aluminium eziphosiweyo, kwiindawo ezifakwe i-hot-dip galvanized okanye kwiipleyiti zentsimbi ezigoqwe ngobushushu ezineemingxuma zesanti okanye iimingxuma ze-pinholes, ngexesha lenkqubo yokubhaka nokunyanga, i-powder coating iyanyibilika kwaye ithambe ngelixa ivala imingxuma yesanti kunye neemingxuma ze-pinholes kumphezulu wento ephosiweyo. Njengoko ubushushu bezinto eziphosiweyo busanda, umoya kwimingxuma yesanti kunye neemingxuma zezixhobo eziphosiweyo uyanda, kwaye uxinzelelo lwangaphakathi nalo luyanda rhoqo. Xa uxinzelelo lwangaphakathi lukhulu kancinci kunamandla e-plastic coating enyibilikisiweyo, umoya wangaphakathi uya kuqhushumba i-coating kwaye wenze amaqamza amancinci ukuze aphume. Ngenxa yempendulo yokuqina kwe-powder coating ngexesha lenkqubo yokwenza ifilimu, i-viscosity yokunyibilika kwe-coating iyanda rhoqo kwaye ekugqibeleni iba yi-solid coating film. Ke ngoko, xa uxinzelelo lwangaphakathi kwi-bubbles ezincinci lungafikeleli kumandla afunekayo ukuze kuqhushumbe ifilimu ephosiweyo, la maqamza amancinci enza amasuntswana okanye ii-granules eziphuma kumphezulu wefilimu ephosiweyo. Xa uxinzelelo lwangaphakathi kwi-bubble encinci lwanele ukuqhuma i-coating, i-bubble encinci iya kuqhawuka kwaye umoya ongaphakathi uya kuphuma uye emoyeni. Ukuba uphahla ngeli xesha lulahlekelwe ngamandla alo okulinganisa kwaye alukwazi ukuvala imingxunya yomoya emincinci evumela umoya ukuba uphume, kuya kubakho amasuntswana okanye iigranules eziqhelekileyo ze-volcanic crater, zibe yingxaki enkulu.
Ukuba ii-defoamers zongezwa kwiingubo zomgubo, zinokunciphisa ukunyibilika kwengubo yomgubo kwaye zinciphise uxinzelelo lomphezulu wengubo. Oku kuvumela umoya kwimingxunya yesanti kunye nemingxuma kumphezulu wento egqunyiweyo, echaphazeleka bubushushu bokubhaka kunye noxinzelelo, ukuba iqhume ngokulula kwaye ithambe ifilimu yogquma engavuthwanga iye emoyeni. Kwangaxeshanye, izikhewu kwifilimu yogquma apho amaqamza aphuma khona nazo zinokuvala ngokulula ukulingana, zithintele ukwakheka kwamaqhekeza kunye namaqhekeza kwifilimu yogquma, okanye amaqhekeza aneemigodi zentaba-mlilo.
Ngenxa yokuba iindlela zokuxovula i-powder ezisetyenziswa emanzini nakwizinto ezinyibilikayo zahlukile ngokupheleleyo kwezo ze-powder coating, ii-defoamers ezisetyenziswa kwi-water-based kunye nezo zinyibilikayo azinakusetyenziswa ngokuthe ngqo kwi-powder coating. Ngenxa yobuchule bee-powder coating, azikho iintlobo ezininzi zee-defoamers ezisetyenziswa kwi-powder coating njengakwi-water-based coating kunye nezinto ezinyibilikayo.
Ixesha leposi: Agasti-15-2025