Munzira yose yekugadzirwa kwemazuva ano PCB, ingi yave imwe yezvinhu zvakakosha zvekubatsira muPCB kugadzira maitiro emafekitori ePCB. Iyo inobata chinzvimbo chakakosha muPCB process zvinhu. Kubudirira kana kukundikana kweinki kushandiswa kunokanganisa zvakananga zvese zvinodiwa zvehunyanzvi uye zviratidzo zvemhando yekutakura kwePCB. Nechikonzero ichi, PCB vagadziri vanoisa kukosha kukuru pakuita kweingi. Kuwedzera kune inozivikanwa inki viscosity, iyo thixotropy seinki inowanzoregererwa nevanhu. Asi inoita basa rakakosha mukuita kwekudhinda skrini.

Pazasi isu tinoongorora uye kuongorora pesvedzero yethixotropy muPCB system pane inki kuita:

1. Screen

Sirika sikirini ndechimwe chezvinhu zvakakosha muchirongwa chekudhinda skrini. Pasina chidzitiro, haikwanise kunzi kudhinda skrini. Kudhinda skrini ndiwo mweya weiyo skrini yekudhinda tekinoroji. Masikirini anenge ese machira esirika (zvechokwadi kunewo machira asiri-sirika).

MuPCB indasitiri, inonyanya kushandiswa ndeye t-mhando mambure. s uye hd mhando network haawanzo shandiswa kunze kwezvido zvemunhu.

2. Ingi

Inoreva gelatinous ine ruvara inoshandiswa pamapuranga akadhindwa. Inowanzo kuumbwa nesynthetic resins, volatile solvents, mafuta uye mafirita, desiccants, pigments uye diluents. Kazhinji inonzi ink.

Tatu. Zvinoverengeka zvakakosha zvehunyanzvi zvePCB inki

Kunyangwe kunaka kwePCB inki kwakanakisa, pamusimboti, hazvibviri kuputsa kubva mukubatanidzwa kwepamusoro pezvikamu zvikuru. Hunhu hwakanakisa hweinki kuratidzwa kwakazara kwesainzi, kufambira mberi uye kuchengetedza kwezvakatipoteredza kweformula. Inoratidzwa mu:

(1) Viscosity: pfupi kune dynamic viscosity. Kazhinji inoratidzwa ne viscosity, ndiko kuti, shear stress yekuyerera kwemvura yakakamurwa nevelocity gradient munzira yekuyerera layer, iyo international unit iPa/sec (pa.s) kana milliPascal/sec (mpa.s). Mukugadzirwa kwePCB, inoreva kuyerera kweinki inogadzirwa nemasimba ekunze.

(2) Plasticity: Mushure mekunge ingi yakanganiswa nesimba rekunze, inoramba ichichengetedza zvinhu zvayo isati yasvibiswa. Iyo yepurasitiki yeinki inobatsira pakuvandudza kurongeka kwekudhinda;

(3) Thixotropic: (thixotropic) Ingi inobwinya kana yasiiwa yakamira, uye kuona kunoshanduka kana ikabatwa. Inonziwo thixotropic uye sag resistance;

(4) Fluidity: (leveling) iyo iyo inki inopararira pasi pekuita kwesimba rekunze. Fluidity ndiyo inodzokororwa ye viscosity, uye fluidity inoenderana nepurasitiki uye thixotropy yeinki. Iyo plastiki uye thixotropy yakakura, iyo fluidity yakakura; iyo fluidity yakakura, iyo imprint iri nyore kuwedzera. Nekuderera kwemvura, kunowanzoita kuumbwa kwetiweki, zvichiita kuti inki igadzire, iyo inonziwo reticulation;

(5) Viscoelasticity: inoreva kugona kweinki inogerwa nekutyoka mushure mekunge ingi yakweshwa nemusviniro kuti idzoke nekukurumidza. Zvinodiwa kuti inki deformation kumhanya nokukurumidza uye ingi rebounds nokukurumidza kuti kubatsira kudhinda;

(6) Kuoma: kunonoka kuomeswa kweinki pachiratidziro, zviri nani, uye nekukurumidza zviri nani mushure mekunge ingi yaendeswa kune substrate;

(7) Fineness: saizi yepigment uye yakasimba zvinhu zvimedu, PCB inki kazhinji isingasviki 10μm, uye saizi yehunyoro hunofanira kunge isingasviki chikamu chimwe muzvitatu chekuvhura mesh;

(8) Kusimba: Kana ingi ikanhongwa nefoshoro yeinki, mwero uyo ingi yakaita sesirika isingatyoki kana yakatambanudzwa inonzi tambo. Ingi filament yakareba, uye kune mafilaments akawanda pamusoro peinki uye nzvimbo yekudhinda, zvichiita kuti substrate uye ndiro yekudhinda zvisvibe, kana kusakwanisa kudhinda;

(9) Transparency uye kuvanza simba reinki: For PCB ingi, siyana zvinodiwa vanoiswa pamberi pachena uye kuvanza simba ingi maererano siyana kushandiswa uye zvinodiwa. Kazhinji kutaura, ingi dzedunhu, ingi dzinoitisa uye ingi dzehunhu zvese zvinoda simba rekuhwanda rakakwirira. The solder resist is more flexible.

(10) Kemikari inopikisa inki: PCB inki ine mitemo yakasimba yeasidhi, alkali, munyu uye solvent maererano nezvinangwa zvakasiyana;

(11) Kuramba kwemuviri kweinki: PCB inki inofanira kusangana nekunze kwekuramba, kupisa kwekutya kupikisa, mechanical peel resistance, uye kusangana nezvinodiwa zvakasiyana-siyana zvekushanda kwemagetsi;

(12) Kuchengeteka uye kuchengetedzwa kwezvakatipoteredza kweinki: PCB inki inodiwa kuve yakaderera-chepfu, isina kunhuhwirira, yakachengeteka uye ine hushamwari.

Pamusoro takapfupikisa zvimiro zvemainki gumi nemaviri ePCB. Pakati pavo, mukushanda kwechokwadi kwekudhinda kwekrini, dambudziko re viscosity rine hukama hwepedyo nemushandi. Iyo viscosity yakakosha kune kutsetseka kwesiriki skrini. Naizvozvo, muPCB ingi magwaro ehunyanzvi uye qc mishumo, iyo viscosity yakanyorwa zvakajeka, ichiratidza pasi pemamiriro api uye ndeupi rudzi rwekushandisa viscosity yekuedza chiridzwa. Muchiito chekudhinda, kana inki viscosity yakanyanyisa, zvichange zvakaoma kudhinda kunze, uye micheto yemifananidzo ichave yakanyanyisa. Kuti uvandudze maitiro ekudhinda, mutete achawedzerwa kuita kuti viscosity isangane nezvinodiwa. Asi hazvina kuoma kuwana kuti muzviitiko zvakawanda, kuti uwane iyo yakanaka resolution (resolution), zvisinei kuti unoshandisa viscosity ipi, hazvigoneke kuita. Sei? Mushure mekutsvakurudza kwakadzama, ndakaona kuti inki viscosity chinhu chakakosha, asi kwete chete. Pane chimwe chinhu chakakosha zvikuru: thixotropy. Iri kukanganisawo kururama kwekudhinda.

Four. Thixotropy

Viscosity uye thixotropy maitiro maviri akasiyana emuviri. Zvinogona kunzwisiswa kuti thixotropy chiratidzo chekuchinja kweinki viscosity.

Kana iyo ingi iri pane imwe nguva tembiricha, tichifunga kuti zvinonyungudutsa muinki hazviputsi nekukurumidza, viscosity yeinki haizochinji panguva ino. Iyo viscosity haina chekuita nenguva. Iyo viscosity haisi shanduko, asi inogara iripo.

Kana iyo inki inoiswa pasi pesimba rekunze (kukurudzira), iyo viscosity inoshanduka. Sezvo simba richienderera mberi, iyo viscosity icharamba ichiderera, asi haizodonhe nekusingaperi, uye inomira kana yasvika kune imwe muganhu. Apo simba rekunze rinonyangarika, mushure meimwe nguva yekumira, ingi inogona kudzokera zvishoma nezvishoma kune yekutanga. Isu tinodaidza rudzi urwu rwekudzoreredzwa kwemuviri pfuma iyo iyo inki viscosity inoderera nekuwedzera kwenguva pasi pechiito chekunze kwesimba, asi mushure mekunge simba rekunze ranyangarika, rinogona kudzokera kune yekutanga viscosity sethixotropy. Thixotropy inguva inoenderana nenguva pasi pekuita kwesimba rekunze.

Pasi pekuita kwesimba rekunze, kupfupika kwenguva yesimba, uye kuderera kuri pachena kweviscosity, tinodaidza iyi inki iyo thixotropy yakakura; pane zvinopesana, kana iyo viscosity inoderera isiri pachena, zvinonzi thixotropy idiki.

5. Reaction mechanism uye kutonga kweinki thixotropy

Chii chaizvo chinonzi thixotropy? Sei viscosity yeinki yakaderedzwa pasi pechiito chekunze kwesimba, asi simba rekunze rinonyangarika, mushure meimwe nguva yenguva, viscosity yepakutanga inogona kudzorerwa?

Kuti uone kana inki ine mamiriro anodiwa ethixotropy, kutanga iresin ine viscosity, uyezve inozadzwa neimwe vhoriyamu reshiyo yekuzadza uye pigment particles. Mushure mokunge resin, mafirita, pigments, additives, nezvimwewo zvakagadzika uye zvakagadziriswa, zvakanyatsosanganiswa pamwe chete. Iwo musanganiswa. Mukusavapo kwekupisa kwekunze kana ultraviolet chiedza simba, ivo varipo seboka reion risingaenzaniswi. Mumamiriro ezvinhu akajairika, anorongedzerwa nenzira yakarongeka nekuda kwekukwezvana, kuratidza chimiro chepamusoro viscosity, asi hapana makemikari anoita. Uye kana ichinge yaiswa pasi pesimba rekunze remagetsi, iyo yekutanga kurongeka kurongeka kunokanganiswa, iyo mutual yekukwezva ketani inogurwa, uye inova isina kurongeka mamiriro, inoratidza kuti viscosity inova yakaderera. Ichi ndicho chiitiko chatinowanzoona inki kubva kugobvu kusvika kutete. Tinogona kushandisa inotevera yakavharwa loop reversible process diagraph kuratidza zvakajeka maitiro ese ethixotropy.

Hazvina kuoma kuwana kuti chiyero chezvimedu muinki uye chimiro uye ukuru hwezvimedu zvinogadzirisa zvinhu zvethixotropic zveinki. Ehe, hapana thixotropy yezvinwiwa izvo zvagara zvakaderera zvakanyanya mu viscosity. Zvisinei, kuitira kuti iite inki yethixotropic, zvinokwanisika kuwedzera mubatsiri wekubatsira kuchinja uye kuwedzera viscosity yeinki, zvichiita kuti thixotropic. Ichi chinowedzera chinonzi thixotropic agent. Naizvozvo, iyo thixotropy yeinki inodzoreka.

Nhanhatu. Kushanda kushandiswa kwethixotropy

Mukushanda kwekushandisa, hakusi kuti mukuru wethixotropy, ari nani, kana kuti muduku ari nani. Zvakangokwana. Nekuda kweiyo thixotropic zvivakwa, iyo inki yakakodzera kwazvo maitiro ekudhinda skrini. Inoita kuti chidzitiro chekudhinda chiite nyore uye chemahara. Munguva yeingi sikirini kudhindwa, iyo ingi pamambure inosundirwa neiyo squeegee, kukunguruka uye kusvinwa kunoitika, uye viscosity yeinki inova yakaderera, izvo zvinoita kuti ingi ipinde. Mushure mekunge ingi yadhindwa paPCB substrate, nekuti viscosity haigone kudzoserwa nekukurumidza, pane nzvimbo yakakodzera yekuenzanisa kuti ingi ifambe zvishoma nezvishoma, uye kana chiyero chadzoserwa, kumicheto yekrini yakadhindwa magirafu achawana inogutsa. flatness.