Author Topic: Will a standard Stouffer 21 Step Sensitivity Guide work for UV LED system?  (Read 6446 times)

Offline JonnyP

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Hi, I'm building a UV LED Exposure Unit, will be using Saati PHU emulsion (I think), and I am trying to calibrate the exposure and see if there are any hot spots on the glass. Wondering if there is any difference among the various exposure guides, and if it matters at all that I'm using UV LED instead of other light sources. Thanks.


Offline Colin

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Light transmission is light transmission.

Using the 21 step calculator will give you your best overall understanding of how solid your emulsion has gotten during your exposure.

You will definitely want to check multiple locations across your screen for proper exposure and "hot or cold" spots.

What is the light source you are getting?  Not all LED's are created equal.....
Been in the industry since 1996.  5+ years with QCM Inks.  Been a part of shops of all sizes and abilities both as a printer and as an Artist/separator.  I am now the Ink and Chemical Product Manager at Ryonet.

Offline Robert Clark

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Great advice Colin !  21 step guide should be in every shop to have a better understanding of what is going on with your exposure unit.
Robert Clark
One Stroke Inks
Senior Account Manager
rclark@osinks.com
(800)942-4447

Offline JonnyP

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Hi, thanks for the responses.
I'm using single point UV LED:   200W UV 395nm~405nm LED Emitter DC30V-36V 6A On Copper PCB, with appropriate driver.

Offline Colin

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You should be fine with that unit.  Its not in the "perfect" wavelength for LED, which is a hard 405nm but you will find success.

What you will find is the emulsion is just a touch "softer" or has more flex than a screen exposed on a hard 405nm or on a Metal Halide.
Been in the industry since 1996.  5+ years with QCM Inks.  Been a part of shops of all sizes and abilities both as a printer and as an Artist/separator.  I am now the Ink and Chemical Product Manager at Ryonet.