Subject: | |
From: | |
Reply To: | |
Date: | Thu, 26 Jun 2008 07:29:58 -0500 |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
I somewhat agree with Graham. Nothing really likes to stick to silicones,
including other silicones. I often have to address the challenge of
conformal coating delaminating over a spot where RTV silicones had been
dripped and then wiped up.
I would suggest plasma etching, most likely oxygen and argon. A fairly
short duration is often effective at solving coating adhesion issues in
problem cases. Many of the mold release agents are either teflon or
silicone based, so will be fairly chemically resistant. That is why the
Ensolv may not be addressing it.
Where I disagree with Graham is the approach of having the component
manufacturer change their most release agent. If you are a Motorola or a
Nokia, and going through a few million components a day, you might have a
little leverage with the component manufacturer. Most of us just have to
take what we can get and don't have the leverage necessary to get changes
made.
Doug Pauls
Rockwell Collins
Graham Naisbitt <[log in to unmask]>
Sent by: TechNet <[log in to unmask]>
06/26/2008 06:05 AM
Please respond to
TechNet E-Mail Forum <[log in to unmask]>; Please respond to
Graham Naisbitt <[log in to unmask]>
To
[log in to unmask]
cc
Subject
Re: [TN] Solithane coating dewetting
Silicone not sticking to silicone - no surprise.
How to remove silicone? Not easy, maybe plasma etching or a really
aggressive solvent.
You need to get back to the component manufacturer and have them
change their mold release or at least control how much they use.
Graham Naisbitt
On 26 Jun 2008, at 07:33, Tan Geok Ang wrote:
> Hi All,
> Quite often, I encountered Solithane coating dewetting
issue
> over some IC moulding (rough or smooth, did not trace what moulding
> material is used) compounds across different suppliers, though the
> whole
> PCBAs are being cleaned with EnSolv. What is the cause of the issue?
> Is
> the cause due to the release agent used during the moulding compound
> process (but why cannot be clean away)?
> Thank in advance!
> Regards
> GA Tan
>
> ---------------------------------------------------
> Technet Mail List provided as a service by IPC using LISTSERV 15.0
> To unsubscribe, send a message to [log in to unmask] with following
> text in
> the BODY (NOT the subject field): SIGNOFF Technet
> To temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]
> : SET Technet NOMAIL or (MAIL)
> To receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]
> : SET Technet Digest
> Search the archives of previous posts at:
http://listserv.ipc.org/archives
> Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16
> for additional information, or contact Keach Sasamori at [log in to unmask]
> or 847-615-7100 ext.2815
> -----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
for additional information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
|
|
|