I believe something about the material having hydroscopic properties; such
that the relative humidity before launch (Florida?) and then subsequent low
pressure in space causing vapor particles to get onto optics.

-----Original Message-----
From: Stephen R. Gregory [mailto:[log in to unmask]]
Sent: Wednesday, November 25, 1998 1:20 PM
To: [log in to unmask]
Subject: [TN] Subj: Re: [TN] SMT ZENER


In a message dated 11/25/98 1:08:58 PM Pacific Standard Time,
[log in to unmask] writes:

<< James and Gregory:
 The only problem with using SMD epoxy to hold the component in place
 during second reflow, is that you will need to qualify a material that
 meets the out-gassing requirements of TRW, and as James know they can be
 pretty stringent depending on the application.
  >>

Florencio,

     Seeing how you brought up something I wasn't aware of, do you know if
Loctite's 3611 (I mis-typed the formula before) meets that? It's a pretty
commonly used thermal cure epoxy for bottomside components...

-Steve Gregory-

P.S. Teach me something, what kinds of problems might be caused by
"outgassing" previously cured epoxy?

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