Process Engineer,
The best method for checking dimensional stability is to check the process
and not each individual phototool. Although you may want to check a few
films in process, time is better spent checking a 'checkplot' film at
regular intervals. Suggested intervals may be morning, noon, and night or
Monday, Wednesday, Friday or whatever gives you a high confidence level. It
is important to chart the results of the measurements to identify any trends
or patterns. The checkplot can have numerous targets to check the accuracy
over a small area as well as over a large area. Your checkplot should also
have features to measure line widths, density, and to indicate possible
pinhole problems.
Many succesful companies have moved to a zero touch up environment.
Although each film is inspected for pinholes or scratches, if any are found
the cause is identified and eliminated and a new film is imaged. This
eliminates the time and labor of touch up, reduces the amount of film
handling, and forces the artwork production team to focus on the process of
proper procedures, maintenance, etc.
Assuming the environment temperature and humidity is controlled and the film
processor and photoplotter are properly maintained, you can begin to rely on
the overall system to produce consistent phototools.
I would recommend against pre-punching the film. This simply adds an
additional step and could introduce unwanted variables into the process.
George Murray
Gerber Systems
[log in to unmask]
----------
From: TechNet-request
To: TechNet
Subject: Phototool dimensional stability
Date: Tuesday, January 07, 1997 3:47AM
Hello:
What have you found to be the best way to check dimensional stability in the
silver halide artwork phototools?
I'm working in a large volume production facility. The artwork design is
sent from a CAM system to the drum laser plotter where it is imaged onto
silver halide film which has been stabilized for at least four hours. Then
it is sent to a developer unit. The plotter and developer system is in a
class 1000 cleanroom.
The next step in the process is to AOI the film for "copper splashes" and
"pinholes." Then the film is touched up.
My major concern is that the film retains its size and shape so that it will
be accurate for imaging manufacturing. Is it best to put targets in the
artwork design around the peripheral of the image and then measure these
targets at various times? Or, is it better to punch holes in the film
around
the edges after equalization and prior to laser exposure to measure the
development process?
I don't want to overdo it putting too many targets on the artwork or in
collecting insufficient data. We do have measuring equipment which is
located within the adjacent film inspection area, which is a class 10,000
cleanroom.
I haven't seen much discussion on the artwork or its creation processes in
this forum. I hope this sparks some discussion. If this has already been
discussed previously, my apologies.
Thank you in advance.
Sincerely,
Process Engineer
***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To unsubscribe from this list at any time, send a message to: *
* [log in to unmask] with <subject: unsubscribe> and no text. *
***************************************************************************
* If you are having a problem with the IPC TechNet forum please contact *
* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] *
***************************************************************************
***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To unsubscribe from this list at any time, send a message to: *
* [log in to unmask] with <subject: unsubscribe> and no text. *
***************************************************************************
* If you are having a problem with the IPC TechNet forum please contact *
* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] *
***************************************************************************
|
