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Bubbles on solder joint(after conformal coating curing)

Bubbles on solder joint(after conformal coating curing)

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Hi All, Recently we are working on the conformal coating ... - Nov 19, 2009 by TMS78

Since the bubbles: * Are only on the solder connection, we'... - Nov 19, 2009 by davef

Hi The bubble shows only around component body after ir re... - Nov 22, 2009 by Jeong Ju-young

Hi Ju Yong, The PCB are dry in an airseal cabinet(Staging... - Nov 22, 2009 by TMS78

Hi Davef, The bubbles occurs at the body also...there's a... - Nov 22, 2009 by TMS78

Search the fine SMTnet Archives [use => confo* and bubb*] to... - Nov 23, 2009 by davef

Hi Davef, Thanks...Saw 1 of your thread that you posted :... - Nov 24, 2009 by TMS78

Why in heavens name are you using a heat or air cure conform... - Nov 25, 2009 by sforman1

Hi sforman1, The chemical that i'm using is a solvent bas... - Nov 29, 2009 by TMS78

totally wrong. a. I do not reccomend Humiseal UV products. M... - Nov 30, 2009 by sforman1

Hi sforman1 Are you refering that the UV is able to cure ... - Nov 30, 2009 by TMS78

What solvent based material. Call me at 972-678-4950. I have... - Dec 01, 2009 by sforman1

UV40 for you info was developed in Humiseal EU and has been ... - Dec 02, 2009 by josh

Josh: This is your choice. It wouldn't be mine. Again, I hav... - Dec 02, 2009 by sforman1

As a large coating house we use 1B73 daily and we have very... - Dec 02, 2009 by Lou

Hi Lou, we are using a fluid dispensing machine. our cur... - Dec 02, 2009 by TMS78

dave, where I work they are having the same problems with 1B... - Dec 18, 2009 by tommyg_fla

Tom: Once again - why are you using solvent based conformal ... - Dec 18, 2009 by sforman1

@tommyg_fla According to the TDS the recommended coating ... - Dec 28, 2009 by kpm

TMS78

#60478

Bubbles on solder joint(after conformal coating curing) | 19 November, 2009

Hi All,

Recently we are working on the conformal coating process using Humiseal chemical 1B73 and thinner 521.

Bubbles on component body/joints are seen after gone through the IR Reflow Oven.

During the conformal coating, only tiny bubbles seen after coating.(the machine is fine,as able to dispense some chemical without bubbles using beam mode)

After staging, the tiny bubbles are gone. Very nioe finishing. But bubbles seen after the IR Curing Reflow Process.

Caused of bubble;;; Suspected 1 :- the tiny bubbles are entrapped into the components body gap which erupted after curing..

Anyone have any experenice in conformal coating process which is able to help advice :

1) is our suspected cause vaild ? - even we do 24hrs environment curing, the bubble still exist..

2) anyway to eliminate the bubbles issue ?

21 Dec 09-Update : Hi All,

We have managed to clear most of the bubbles issues on most of the components:- with the help and advice from everyone that contributed in this forum.. Really appreciate the advice.

The only isssue that we are seeing now is mainly along the IC Lead - i have attached a picture of the Chemical merging/form along the IC lead. Can anyone advice is the chemical merging along the IC lead acceptable. Is that consider as Bubbles (although it look like it is)?

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