Coating kugadzira nzira

Coating-forming process inogona kukamurwa kuita melt coalescence kuti igadzire firimu rekunamira rinodzika matanho matatu.

Pane imwe tembiricha yakapihwa, kutonga kwakanyungudutswa coalescence mwero chinhu chinonyanya kukosha ndeyekunyunguduka kweresin, viscosity yekunyunguduka kwehupfu hwehupfu uye ukuru hwehupfu. Kuti zvive zvakanakisa coalescence yeyakanyungudutswa ichakurumidza sezvinobvira, kuitira kuti tive nenguva yakareba yekupedzisa leveling phase kuyerera mhedzisiro. Kushandiswa kwemushonga wekurapa kwakapfupikiswa kuwanikwa kuyerera uye kuenzana kwenguva inodiwa, uye nekudaro firimu rekunamira rinoumbwa neaya anonyanya kushanda poda rinowanzo ratidza peel yeorenji.

Izvo zvakakosha zvinokanganisa kuyerera kwekuvhara uye kuenzana ndeyekunyunguduka viscosity yeresin, kushushikana kwepamusoro kwehurongwa uye ukobvu hwefirimu. Zvakare, iyo yakanyunguduka viscosity, kunyanya zvinoenderana nekushisa kwekurapa, chiyero chekurapa uye mwero wekupisa.

Zvinhu zvakasiyana-siyana zvataurwa pamusoro apa, pamwe chete nekugovera saizi yechikamu uye ukobvu hwefirimu, kazhinji kunotemerwa neinodiwa firimu zvivakwa kuti zvipendiwe zvinhu uye hupfu hwekuvaka mamiriro akasarudzwa. Chipfeko chemafu kuyerera uye kuenzana kwesimba kubva kune tension yepasi peiyo system, iyi yekumberi yakataurwa zvakare. Simba rinoshandiswa pakukwezva pakati pemamorekuru mufirimu yekuputira pane zvinopesana, mhedzisiro, senge melt viscosity yakakwira, iyo yakanyanya kupikisa kuyerera uye kuenzana. Saka, kudzvinyirirwa kwepamusoro, uye saizi yemamorekuru yemusiyano pakati pesimba rinokwevera zvinhu zvinotaridza kuwanda kweiyo firimu yekuputira.

Nokuda kwekuputira nekuyerera kwakanaka, zviri pachena kuti kudzvinyirirwa kwepamusoro kwegadziriro kunofanira kunge kwakakwirira sezvinobvira, uye kunyunguduka kweviscosity kwakaderera sezvinobvira. Izvi zvinogona kuwanikwa kuburikidza nekuwedzera izvo zvinowedzera kune tension yepasi peiyo system inogona kuvandudzwa uye kushandiswa kwenzvimbo yakaderera yekunyungudika ye resin yepasi molecular uremu.

Coating-forming process

Coatings inogona kugadzirirwa maererano nepamusoro pemamiriro ezvinhu ane yakanakisa kuyerera zvivakwa, asi nekuda kweiyo yakakwira yepamusoro tension inokonzera shrinkage, nekuda kweiyo yakaderera melt viscosity inoburitsa sagging, uye makona Kusakwana coatability. Mune basa rinoshanda, kushushikana kwepamusoro uye kunyunguduka viscosity yehurongwa kunodzorwa mukati meiyo yakatarwa siyana, saka inokwanisa kuvharidzira kutaridzika kwepamusoro kunogona kuwanikwa.

Mhedzisiro yehutano hwepamusoro uye yakanyunguduka viscosity yekuyerera kwefirimu yekuputira inoratidzwa mumufananidzo 2. Sezvinogona kuonekwa mumufananidzo, kupindirana kwepamusoro kweyakanyanya kuderera kana kuti yakanyanya kunyunguduka viscosity ichadzivirira kuvhara kuyerera, zvichiita kuti a coating firimu urombo kuyerera, uye pamusoro tension yakanyanyisa firimu kuumba maitiro achaonekwa craters. Iko kugadzikana kwekuchengetedza kwemuviri kweiyo melt viscosity yakanyanya kuderera kuchaita kuti hupfu huve hwakaipa Husina kunaka hwekubatika kwekona yekuvaka, uye kuvakwa mune facade kudonha.

Muchidimbu, zviri pachena, iyo yekupedzisira pamusoro peiyo yakawanikwa yeupfu yekuputira firimu, kukanganisa uye kushomeka (seorenji peel, kushata kuyerera, craters, pinholes, nezvimwewo) zvakabatana zvakanyanya, uye zvakare mune deposition process inobatanidzwa mu kuchinja kwechikamu mu rheological force control. Iyo poda particle saizi yekugovera inokanganisawo kutaridzika kwepamusoro kweiyo firimu yekuputira. Izvo zviduku zviduku, zvimedu zvakakura zvepasi nekuda kwehutano hwayo hwekupisa, saka nguva yekunyunguduka ipfupi pane iyo yezvikamu zvakakura, coalescents zvakare nekukurumidza, uye zviri nani kutaridzika kwepamusoro pefirimu yekuputira inoumbwa. Huru hupfu hwehupfu nguva yekunyunguduka kupfuura kureba kwezvimedu zvidiki, iyo yekunamira firimu inoumbwa pairi inogona kugadzirwa iyo orenji peel athari. Electrostatic poda yekuvaka nzira (corona discharge kana friction discharge), asi zvakare inotungamira mukuumbwa kwechimwe chinhu muorenji peel.

Maitiro ekudzikisa kana kudzivirira iyo orenji peel athari kusimudzira kuyerera uye kuenzana kunogona kuderedza kana kudzivirira peel yeorenji. Iyo sisitimu inoshandisa yakaderera kunyungudika viscosity, kuyera yakawedzera nguva uye yakakwira kumusoro kushushikana mukurapa maitiro kunogona kuvandudzwa kuyerera uye kuenzana. Iwo akakosha maparamendi ekudzora epamusoro tension gradient akaderedzwa orenji peel, ukuwo kudzora kushushikana kwepamusoro peiyo yekuputira firimu repamusoro yunifomu, kuitira kuti uwane iyo diki nzvimbo.

Inoyerera-inosimudzira mumiriri kana mumiriri wekuenzanisa inowanzoshandiswa mubasa chairo kuvandudza kutaridzika kwejasi, kuitira kubvisa kuremara kwepamusoro senge orange peel, craters, pinholes. Kuita kwakanaka kweanoyerera-anosimudzira mumiriri anogona kuderedza kunyunguduka viscosity, nokudaro zvichibatsira mukunyunguduka kusanganiswa uye pigment kupararira, kunatsiridza kunyorova kwe substrate, kuyerera uye kuenzana kwejasi, kunobatsira kubvisa kuremara kwepamusoro zvakare. sekufambisa kusunungurwa kwemhepo.

Iyo inoyerera inogadzirisa dosage uye hukama hukama hunofanirwa kuongororwa. Huwandu husina kukwana hunokonzeresa shrinkage uye orenji peel, kunyanyisa kunwa kunotungamira mukurasikirwa kwegloss, haze, uye kuburitsa recoat adhesion matambudziko pamusoro. Kazhinji, iyo inoyerera inogadzirisa mune premix yakawedzerwa. Kana kuti yakagadzirwa neresin master batch (resin uye chiyero chekuwedzera che9/1 kusvika 8/2), kana inoshambadzirwa pane inorganic inotakura muhupfu. Huwandu hwezvinowedzera mupendi yehupfu ndeye 0.5 kusvika 1.5% (muBinders yakaverengerwa inobudirira polima), asi pakudzika kwakadzika kunogonawo kunaka.

Polyacrylate flow modifier resin inonyanya kushandiswa, senge polyacrylic acid butyl ester ("Acronal 4F"), acrylic acid ethyl - ethyl hexyl acrylate copolymer uye butyl acrylate - acrylic acid-hexyl acrylate copolymer, nezvimwewo. wide concentration range. Kazhinji polyacrylate diki mhedzisiro pakumanikidzana kwepamusoro, ivo vanogona kubatsira mukuputira kuumba inogara yakafanana yunifomu pamusoro. Kuenzaniswa neaya epamusoro tension ekudzikisa ekuwedzera (senge silicone kana zvimwewo), iwo haaderedze kushushikana kwepamusoro, uye nekudaro anogona kushandiswa kukurumidza kukwira. Deredza kusawirirana kwepamusoro kwezvinowedzera zvinosanganisira pamusoro peanoshanda maajenti, fluorinated alkyl esters, uye silicone. Vanojoinha mari iri very sensitive. Benzoin is degassing agent, inewo mhedzisiro yekudzikisa kushushikana kwepamusoro, inoshandiswa zvakanyanya kuvandudza kutaridzika kwepamusoro kweiyo bhaisikopo rehupfu.

Coating kugadzira nzira