Hi Marco,

you are right to pre-stabilise film but it must be removed from the pack to
let the air circulate freely around each sheet. The longer you can give it
the better but 8 hours is sufficient. There is no need to stabilise at such
a high RH. Pick the conditions that match the environment in which the film
will be used.

As long as the film is stabilised and used in the same environmental
conditions it will not move. This applies to silver halide as well as diazo
film. Make sure you only use 0.007" base film as this is more stable than
0.004".

Paul Gould
Teknacron Circuits Ltd


-----Original Message-----
From: Marco Biagtan <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Date: 06 August 1998 08:16
Subject: [TN] Film Stabilization


>Hi everyone!
>
>I'm currently involved in the production of artwork for pcb manufacturing
>and one major problem that we have is film stability.  To my knowledge, raw
>films have to be pre-stabilized before use and again stabilized after
>processing at constant RH and temp (usually 55% and 23C) for 2 to 4 hours.
>If RH or temp increases, the dimension increase and vice versa.  But what
>if raw films are pre-stabilized at a lower RH (say 45%) and after
>processing these are stabilized also at the same RH.  Will the film still
>experience shrinkage even if it was stabilized at constant RH? (Same
>question also for Temp)
>
>If anyone can help me with this one, I'd appreciate it.  Thanks!
>
>Marco Biagtan
>Artwork Process
>NEC Components Philippines Inc.
>[log in to unmask]

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