Would a Thermal Imagesetter produce quality negs for plates?

I have read a lot of different posts regarding producing film for photopolymer plate making, and a primary concern I have seen is the problem with chemical life… So I was wondering if a thermal imagesetter would be an acceptable alternative, as they do not use any chemicals…

I understand that the resolution is lower, but it has to be better than transparencies printed on a laser printer—right?

If you would like to review some “specs” that I saw, check here http://www.rti-rips.com/ImagesetterSystems.html and then click on a model.

What is the lowest resolution you have ever used to produce a negative?

Thank you in advance for your input. I appreciate it.

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resolution looks low, but I wonder about these types of devices. Saw one come up on wirebids last week:


If they are Computer-to-Plate (CTP), they probably don’t produce a negative at all. They image the plate directly either by laser or some other method. This is the standard method of producing offset plates nowadays. At my work, we use a machine that images directly to polyester film plate material via infrared laser. While the plate material is made in basically the same way as photographic film, it isn’t transparent and can’t be used to shoot photopolymer (or anything else). You’ll have to check and see if these machines can be used to make transparencies.

Michael Hurley
Titivilus Press
Memphis, TN

Thanks for the input so far… This is not a CTP system; but rather a Thermal Imagesetter—it produces output as film negatives; just like a standard imagesetter…

The primary differences I have noticed are a) they do not use chemicals to develop the negative and b) the resolution and line screen are lower.

I would request a piece of film from the manufacturer which has already been imaged by one of these machines. The image on the film should preferably have some thin lines, thin line (and other) reverses, solids, and type (they probably have a test pattern with this on it already, which also specifies what the width of the lines is supposed to be, etc.). In the unlikely event that you plan to print screen tints and halftones, then these should be on the test plate as well. When you get the imaged film, examine the lines, reverses, and edges of the images for smoothness. If you like the way the images look, then it might be OK for you.

One other thing you should do is to hold the film up to a fluorescent tube or incandescent light bulb on the ceiling and see if you can see light through the solid black areas of the film. If you can see light, then you may have trouble exposing photopolymer plates because the light which goes through the black areas may cause image to be created on the plate where you don’t want it to be.

I would be interested to hear what you find……please keep us posted.

Hope this helps.

If you are looking for a chemical free proces, there is an already established high quality method in the graphic arts industry: laser ablation film. This film as furnished, has an overall black layer. When put through an imagesetter designed to image it, an infra-red laser ablates (think “burns away”) the black layer in the image areas, creating a negative. If you put “laser ablation films” into your favorite search engine, you will get information about the films and the imagesetters designed for it.