Vicka,

I have cracked/split the cover coat like this when I used silicon rubber against the surface and laminated it with too high of pressure.   The rubber sticks to the Kapton and moves under high pressure which will split the surface.

That is the only time I have seen it. If you are having this after the board is bent, then the covercoat may have been thinned by such a lamination or the adhesive is for some reason not flexible.  I don't know if that helps

Mike Hill
Quality Manager
TTM Sterling Virginia

-----Original Message-----
From: IPC-600-6012 [mailto:[log in to unmask]] On Behalf Of Hammill, Vicka (EHCOE)
Sent: Wednesday, October 28, 2015 11:56 AM
To: [log in to unmask]
Subject: [IPC-600-6012] Flex quesstion

Has anyone ever seen this condition of cracking of the Kapton on a flexible part of a  rigid flex?   If so, do you the cause?   We have done crossections on this and it showed the kapton only cracking...the adhesive was not cracked and remained untouched.  So far, we have found no specific reason for the cause.
Any input would be appreciated.




Vicka Hammill
Staff Engineer/PB CAA

Honeywell
Lync Phone: 480-627-5547
FAX: 602-436-1005
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