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 papa kaapuni i paʻi ʻia (PCB) ua ʻike maka ʻia e ka poʻe a puni ka honua. 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. Eia nō naʻe, ʻokoʻa kēia PCBS i ka hana, ka paʻakikī, ka uku o ka hana ʻana, ka maikaʻi a me ka hilinaʻi. Kuhi kēia ʻatikala i nā helu hope ʻelua, ka maikaʻi a me ka hilinaʻi o PCBS.

ʻAe, makemake mau nā mea kūʻai aku i nā uila uila kiʻekiʻe, akā pipiʻi loa kēia a hiki ke hoʻopili i nā kaʻina hana paʻakikī. I ke kaʻina paʻakikī o ka hana ʻana a PCB, ka ʻākoakoa ʻana a me ka hoʻāʻo ʻana, aia kahi hana nui i kapa ʻia ʻo “conformal coating” o PCB. He mea nui kēia uhi kūlike i PCBS e pili ana i ka maikaʻi a me ka hilinaʻi.

He aha ka uhi conformal a me kāna mea nui:

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.

Hiki ke lahilahi ke uhi kūlike me 25 microns a “kūlike” i ke ʻano a me ka hoʻonohonoho o ka papa kaapuni. E like me ka mea i ʻōlelo ʻia ma luna, ʻo ke kumu o ka hoʻopili ʻana i ka uhi kūlike i ka ʻilikai (luna a me lalo) o kahi PCB e pale aku i ka PCB mai nā kūlana kūwaho kūwaho kūwaho, a laila e hoʻonui ai i ke ola lawelawe o ka PCB a me nā pono uila e pili pū ana.

E like me nā mahana wela i ʻike ʻia ma nā ʻoihana, nā hale hana, a me nā uila uila kiʻekiʻe, hiki i kēia PCBS me nā uhi kūlike ke kū i nā mahana wela. Pēlā nō, hoʻopili ʻia nā pono uila i hoʻonohonoho ʻia i nā wahi / nā wahi kokoke i ke kai a i ʻole ke kai e ke kiʻekiʻe o ka wai, e like me ka hoʻokele ʻana o nā lako kaua uila uila i ka ʻaʻai / ʻaʻai e hiki ai i ka hoʻoheheʻe hao. 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.

Pehea e hoʻopili ai i ka uhi kūlike?

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.

ʻO nā kumu nui e hoʻoholo ana i ka noi pono o nā pale conformal:

1- Mānoanoa o ka pena

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- Pena me ka lima me ka palaki

2- Ka uhi Aerosol

3- Atomizing spray gun coating

4- Automatic dip coating

5- Automatic selection of coating

Conformal ka penaʻana hoʻōla / hoʻomaloʻo hana:

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- Hoʻōla condensation: Hoʻomaloʻo ʻia ka uhi conformal o PCB i ka mahana o ka mahana, hoʻomoʻomaʻu ka lewa i ka lewa i ka hana hoʻōla a hoʻomaloʻo paha.

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 – Hoʻola lāʻau: Ma kēia hana, hōʻike ʻia nā mea pili PCB i kahi lewa ākea me ka nui o ka oxygen lewa, e kōkua ai i ka hoʻomaloʻo / hoʻōla ʻana i nā mea hoʻoliʻiliʻi hoʻokumu

5- Catalytic curing: This is the process of curing conformal coating in which two materials are fused together, one of which is conformal coating. I ka manawa e hoʻopili ʻia ka uhi me nā mea catalyst ʻē aʻe, ʻaʻole hiki ke hoʻōki ʻia ke kaʻina hana hoʻōla a hiki i ka pau ʻana.

Classification of conformal coatings:

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

L Acrylic kēpau (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.

maika:

1 – kumu kūʻai haʻahaʻa

2- Maʻalahi no nā polokalamu lopako a manuahi paha

3- Easy to rework

4- Ka palekana o ka wai maikaʻi

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

keakea:

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

2- Mālama haʻahaʻa i ka viscosity

3- Ke kūpaʻa o ke kapa haʻahaʻa a me ke kūpaʻa kūlohelohe

L Epoxy conformal coating (ER) :

Hiki ke hoʻopau ʻia nā pale Conformal e pili ana i nā epoxy resins e ka palaki lima, ka ʻehu a i ʻole ke ʻū iho i ka uhi. Paipai ʻia ka pīpī no nā puke nui a no ka liʻiliʻi liʻiliʻi a i ʻole prototype PCBS.

maika:

1- High moisture resistance and good dielectric resistance

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

keakea:

1-epoxy conformal paint is very hard and rigid and can damage PCB and its components if attempted peeling or removal. Wehe i ka uhi ʻana me ka hoʻohana ʻana i kahi mea hoʻoheheʻe hoʻoweliweli

2- Hana maikaʻi haʻahaʻa haʻahaʻa

3 – Hoʻohaʻahaʻa kiʻekiʻe

4- Paʻa lākou i ka hana hou

L Silikone kēpau (OSR) kūlike ka pena ʻana:

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

maika:

1- Kūpaʻa kūpilikiʻi maikaʻi, kūpaʻa kūpale, ʻehu paʻakai a me nā mahana kiʻekiʻe a hiki i 200 OC

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

3- Kūpono no nā noi waho PCB me ka wela kiʻekiʻe

ʻO ka meaʻino:

1- ʻAʻole e ʻaʻa i ke kūpale ma muli o nā waiwai o ke kāpili

2- Hiki ke hana hou ʻia, akā ʻaʻole maʻalahi, e koi ana i nā mea hoʻoheheʻe kūikawā, nā manawa pulu lōʻihi a hoʻouluulu e like me ka palaki a me ka ʻauʻau ultrasonic.

3- Low mechanical strength, weak adhesion to PCB substrate

L Polyurethane (PU) hoʻopili kūlike:

Kūpono no nā noi PCB i ka kaʻa, ʻoihana, nā pono hana a me nā kelekila. I ka aerospace, i ke kikoʻī, e kuʻikuʻi mau nā mahu wahie me ka kino nui o nā pono uila a no laila komo i loko a pili i ka papa PCB

maika:

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

keakea:

1- Ma hope o ka manawa lōʻihi o ke kaʻina hana hoʻōla piha, huli ia i melemele i nā mahana kiʻekiʻe ma muli o ka nui o ka ʻike VOC

2- E like me ke silikone, ʻaʻole maʻalahi e hemo loa

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.

maika:

1- Excellent dielectric strength

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

3- Can be applied evenly with very thin paint.

keakea:

1- paʻakikī loa ka disass Assembly / rework

2- ʻO ke kumukūʻai kiʻekiʻe ka drawback nui loa.