Kòm nou tout konnen, pwogrè nan kontinyèl nan ekipman elektwonik ak sikwi teknoloji, pikwa nan jeni atizay nan konsepsyon, devlopman ak fabrike nan an lèt detache sikwi tablo (PCB) te temwen pa moun atravè mond lan. 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. Sepandan, PCBS sa yo diferan nan fonctionnalités, konpleksite, pri fabrikasyon, kalite ak fyab. Atik sa a konsantre sou de dènye pwen yo, bon jan kalite a ak fyab nan PCBS.

Wi, kliyan potansyèl toujou vle elektwonik kalite siperyè, men sa a trè chè epi yo ka enplike pwosesis fabrikasyon konplèks. Nan pwosesis konplèks fabrikasyon PCB, asanble ak tès, gen yon pwosesis trè enpòtan ki rele “kouch konfòm” PCB. Sa a kouch konfòme trè enpòtan nan PCBS an tèm de bon jan kalite ak disponiblite.

Ki sa ki kouch konfòm ak enpòtans li yo:

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.

Kouch la konfòm ka mens tankou 25 mikron ak “konfòme” nan fòm nan ak eleman Layout nan tablo a sikwi. Kòm mansyone pi wo a, rezon ki fè yo pou aplike pou yon kouch konfòm sou sifas la (anwo ak anba) nan yon PCB se pwoteje PCB la soti nan kondisyon negatif anviwònman ekstèn, kidonk ogmante lavi sa a ki sèvis nan PCB la ak ekipman ki asosye elektwonik.

Tankou tanperati ki wo yo te jwenn nan endistriyèl, faktori, ak gwo pouvwa elektwonik, PCBS sa yo ak penti konfòmèl ka kenbe tèt ak tanperati ekstrèm. Menm jan an tou, ekipman elektwonik enstale nan zòn / zòn tou pre lanmè a oswa lanmè ka afekte pa imidite segondè, tankou navigasyon ekipman elektwonik naval ka sijè a korozyon / ewozyon ki ka mennen nan oksidasyon metal. 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.

Kouman pou aplike pou kouch konfòm

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.

Faktè prensipal yo ki detèmine aplikasyon an apwopriye nan penti konfòmèl yo se:

1- Epesè nan penti abazde

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- Penti alamen ak yon bwòs

2- kouch Aerosol

3- Atomizing spray gun coating

4- Automatic dip coating

5- Automatic selection of coating

Kouch konfòm geri / siye metòd:

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.

2- Kondansasyon geri: Se kouch nan konfòm nan PCB cheche nan tanperati anbyen, imidite nan atmosfè a ralanti pwosesis la geri oswa siye.

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- Oksidasyon geri: Nan metòd sa a, konfòmè PCB yo ekspoze a yon anviwònman lè ouvè ak gwo kantite oksijèn atmosferik, ki pral ede nan siye / geri nan konfòm ki baze sou sòlvan.

5- Catalytic curing: This is the process of curing conformal coating in which two materials are fused together, one of which is conformal coating. Yon fwa kouch la fusion ak lòt materyèl katalis, pwosesis geri a pa ka sispann jiskaske li fini.

Classification of conformal coatings:

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

L Acrylic résine (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.

Benefis:

1 – pri ki ba

2- Fasil pou aplikasyon pou robo manyèl oswa otomatik

3- Easy to rework

4- Ekselan pwoteksyon imidite

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

Dezavantaj:

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

2- Low antretyen viskozite

3- Low rezistans mete ak rezistans chimik

L Epoxy conformal coating (ER) :

Penti konfòm ki baze sou rezin epoksidik ka ranpli nan men bwòs, espre oswa kouch plonje. Flite rekòmande pou pi gwo komèsan ak pou pi piti volim oswa pwototip PCBS.

Benefis:

1- High moisture resistance and good dielectric resistance

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

Dezavantaj:

1-epoxy conformal paint is very hard and rigid and can damage PCB and its components if attempted peeling or removal. Retire kouch la lè l sèvi avèk yon sòlvan danjere

2- Pòv pèfòmans tanperati ki ba

3- Segondè kontraksyon geri

4- Yo difisil pou refè

L silikon résine (OSR) kouch konfòm:

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

Benefis:

1- Bon rezistans chimik, rezistans imidite, sèl espre ak tanperati ki wo jiska 200 OC

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

3- Apwopriye pou aplikasyon pou PCB deyò ak imidite segondè

Move a:

1- Pa mete rezistan akòz pwopriyete kawotchou

2- Èske yo ka retravay, men pa fasil, ki egzije Solvang espesyal, tan tranpe long ak vibran tankou yon bwòs oswa beny ultrasons

3- Low mechanical strength, weak adhesion to PCB substrate

L an poliyiretàn (PU) kouch konfòm:

Apwopriye pou aplikasyon PCB nan otomobil, endistriyèl, instrumentation ak telekominikasyon yo. Nan aerospace, an patikilye, vapè gaz toujou ap fè kolizyon ak kò prensipal la nan ekipman elektwonik e konsa rantre nan enteryè a ak afekte tablo PCB la.

Benefis:

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

Dezavantaj:

1- Apre yon bon bout tan nan pwosesis geri konplè, li gen tandans vire jòn nan tanperati ki wo akòz kontni segondè VOC li yo

2- Tankou Silisyòm, li pa fasil pou retire nèt

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.

Benefis:

1- Excellent dielectric strength

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

3- Can be applied evenly with very thin paint.

Dezavantaj:

1- Demantèlman / rivork trè difisil

2- Pri segondè se dezavantaj nan pi gwo.