As we all know, the continuous progress of electronic equipment and circuit technology, the peak of engineering art in the design, development and manufacture of boto ea potoloho e hatisitsoeng (PCB) e pakiloe ke batho ho pota lefatše. Our planet is full of highly intelligent machines, automated robots and scientific marvels, and of course, there are plenty of PCBS in every corner of the planet, no matter what country or city it is. Leha ho le joalo, li-PCBS tsena li fapana ka ts’ebetso, ho rarahana, litšenyehelo tsa tlhahiso, boleng le ho ts’epahala. Sengoloa sena se shebile lintlha tse peli tsa ho qetela, boleng le ts’epahalo ea PCBS.

E, bareki bao e ka bang bareki ba lula ba batla lisebelisoa tsa boleng bo holimo, empa sena se theko e boima haholo ‘me se ka kenyelletsa lits’ebetso tse rarahaneng tsa tlhahiso. Ts’ebetsong e rarahaneng ea tlhahiso ea PCB, kopano le liteko, ho na le ts’ebetso ea bohlokoahali e bitsoang “conformal barging” ea PCB. Seaparo sena se lumellanang se bohlokoa haholo ho PCBS ho latela boleng le ho ts’epahala.

Seaparo se lumellanang ke eng le bohlokoa ba sona:

Conforming coating, an ultra-thin protective coating of polymer film, can be used in conjunction with assemblies mounted on assembly surfaces to protect assembly leads, solder joints, exposed wiring, and other metal points on the PCB surface from corrosion, dust, or chemicals due to various operating or environmental conditions.

Seaparo se lumellanang se ka ba tšesaane joalo ka li-microne tse 25 mme sa “ikamahanya” le sebopeho le sebopeho sa karolo ea boto ea potoloho. Joalokaha ho boletsoe kaholimo, lebaka la ho sebelisa seaparo se tšoanang holim’a metsi (holimo le tlase) ea PCB ke ho sireletsa PCB maemong a mabe a kantle ho tikoloho, ka tsela eo ho eketsa bophelo ba ts’ebeletso ea PCB le lisebelisoa tse amanang tsa elektroniki.

Joalo ka lithemparetjha tse phahameng tse fumanehang indastering, fekthering le motlakase o nang le matla a maholo, li-PCBS tsena tse nang le liaparo tse lumellanang li ka mamella maemo a phahameng a leholimo. Ka mokhoa o ts’oanang, lisebelisoa tsa elektroniki tse kentsoeng libakeng / libakeng tse haufi le leoatle kapa leoatleng li ka angoa ke mongobo o phahameng, joalo ka ho tsamaisa thepa ea sekepe ea elektroniki e ka angoa ke ts’enyeho / khoholeho ea metsi e ka lebisang ho ts’oaetso ea tšepe. Similarly, in microbiology laboratories and the medical industry, sensitive electronic equipment can be exposed to toxic chemicals, acidic and alkaline solvents that can accidentally spill onto a PCB, but the PCB’s “conformation coating” will protect the PCB and components from fatal injury.

U ka kenya kopo joang?

In fact, the method of applying “conformal paint” in the right way is so important that careful consideration must be given to how conformal paint is applied. It is as important to choose suitable conformal coating materials.

Lintlha tsa mantlha tse khethollang ts’ebeliso e nepahetseng ea liaparo tse lumellanang ke tsena:

1- Botenya ba pente

2- The level of coverage achieved

3- The degree of adhesion of paint to wood panels and their components.

There are five methods for applying conformal coatings:

1- Penta ka letsoho ka borashe

2- Ho roala sefofane

3- Atomizing spray gun coating

4- Automatic dip coating

5- Automatic selection of coating

Mokhoa o tloaelehileng oa ho folisa le ho omisa:

Conformal coatings themselves can be classified according to the drying and curing methods used after conformal coatings are completed. These methods are:

1- Heat/heat curing: Conformal coating is dried at high temperature. Drying rate is much faster than normal room temperature drying/curing.

Phekolo ea 2- condensation: Ho koaheloa ka mokhoa o tšoanang oa PCB ho omisitsoe ka mocheso o haufi, mongobo sepakapakeng o fokotsa ts’ebetso ea ho folisa kapa ho omisa.

3- ULTRAVIOLET (UV) curing: Here PCB with conformal coating is exposed to UV radiation. The uv energy determines the curing speed of PCB conformal coating

4- Pholiso ea ho tlola moea: Ka mokhoa ona, li-conformers tsa PCB li pepesetsoa tikoloho e bulehileng e nang le oksijene e ngata ea sepakapaka, e tla thusa ho omiseng / ho folisa li-conformers tse its’etlisang

5- Catalytic curing: This is the process of curing conformal coating in which two materials are fused together, one of which is conformal coating. Hang ha seaparo se kopantsoe le lisebelisoa tse ling tsa ts’ebetso, ts’ebetso ea ho folisa e ke ke ea emisoa ho fihlela e felletse.

Classification of conformal coatings:

There are five main conformal coatings used: acrylic resin, epoxy resin, silicone, polyurethane (PU) and polyparaxylene coating.

L Acrylic lehoakhoa (AAR):

Acrylics are ideal for (low-cost and high-volume) common electronics because AAR is inexpensive and can be easily applied to PCB surfaces by brush, dip, and manual or automatic spraying, reducing turnaround time and producing cost-effective products.

melemo e:

1 – theko e tlase

2- E bonolo bakeng sa lits’ebetso tsa li-robot kapa tse iketsang

3- Easy to rework

4- Tšireletso e ntle ea mongobo

5- Good surface elasticity, can withstand static voltage discharge, and does not react with the atmosphere, therefore helps cure through solvent evaporation

go tlhoka mesola:

1- Due to the use of atmospheric curing/drying methods for this material, proper ventilation systems need to be ensured

2- Tlhokomelo ea viscosity e tlase

3- Ho itšireletsa ka tlaase le ho hanyetsa lik’hemik’hale

L Epoxy conformal coating (ER) :

Ho roala ka tsela e lumellanang ho latela li-epoxy resin ho ka phetheloa ka borashe ea letsoho, ho fafatsa kapa ho roala. Ho nyanyatsoa ho khothaletsoa meqolo e meholo le bakeng sa li-PCBS tse nyane haholo.

melemo e:

1- High moisture resistance and good dielectric resistance

2- Excellent chemical resistance, abrasion resistance, moisture resistance and high temperatures up to 150 O C

go tlhoka mesola:

1-epoxy conformal paint is very hard and rigid and can damage PCB and its components if attempted peeling or removal. Tlosa seaparo ka ho sebelisa sesepa se kotsi

2- Ts’ebetso e tlase ea mocheso o tlase

3- Ho folisa shrinkage e phahameng

4- Ho thata ho li etsa bocha

L Silicone lehoakhoa (OSR) conformal barbotage:

The softest of the above two types of conformal coatings is silicone resin (OSR) conformal coatings. They are widely used in LED lamp PCBS without reducing light intensity or color change. Ideal for PCB installation at high humidity and exposure to air. Suitable for PCB with high operating temperature and high power

melemo e:

1- Ho hanyetsa lik’hemik’hale hantle, ho hanyetsa mongobo, ho fafatsa letsoai le lithemparetjha tse phahameng ho fihlela ho 200 OC

2- Good flexibility makes it resistant to vibration stress on PCB from external environment.

3- E loketse lits’ebetso tsa kantle tsa PCB tse nang le mongobo o phahameng

E mpe:

1- Se ke ua apara manganga ka lebaka la thepa ea rabara

2- E ka sebelisoa bocha, empa eseng ha bonolo, e hlokang li-solvent tse ikhethileng, linako tse telele tsa ho inela le ho sisinyeha joalo ka borashe kapa bate ea mahlaseli

3- Low mechanical strength, weak adhesion to PCB substrate

L Polyurethane (PU) liaparo tse lumellanang:

A loketse bakeng sa dikopo PCB ka likoloi, liindasteri, ditlabelwa le puisano. Haholo-holo sebakeng sa marulelo, mouoane oa mafura o lula o thulana le ‘mele o moholo oa lisebelisoa tsa elektroniki mme ka hona o phunyeletse kahare mme o ame boto ea PCB

melemo e:

1- High resistance to moisture, chemicals (acid and alkali) and wear

go tlhoka mesola:

1- Kamora nako e telele ea ts’ebetso e felletseng ea ho folisa, e tloaetse ho fetoha bosehla maemong a phahameng a leholimo ka lebaka la boleng ba eona bo phahameng ba VOC

2- Joaloka silicone, ha ho bonolo ho e tlosa ka botlalo

L polyparaxylene conformal coating:

This type of coating is suitable for avionics, microelectronics, sensors, high-frequency circuits, and densely populated PCB-based components. It is applied by means of vapor deposition.

melemo e:

1- Excellent dielectric strength

2- High resistance to moisture, solvents, extreme temperatures and acid corrosion

3- Can be applied evenly with very thin paint.

go tlhoka mesola:

1- Ho qhaqha / ho rework ho thata haholo

2- Litsenyehelo tse phahameng ke bothata bo boholo ka ho fetisisa.