Negatives for Trident Photopolymer Plates
There are a number of different ways to make negatives for Photopolymer plate but we only recommend photographic negatives. This data sheet will explain the reasons why we only recommend these types of negatives.
Typical methods of making negatives:
1. Laser Negative.
2. Inkjet Negative.
3. Laser Foil Negative.
4. Photographic Negative.
4a. Image Setter
4b. Process Camera
1. Laser negatives are quite popular in craft rubber stamp making, but as the density of black toner is poor, the resulting stamps are not of the highest quality. There has been a tendency to use toner black solvents with heat to effectively enhance the black toner. This method did help but the laser printer manufacturers have changed the laser toner technology in recent years. They have added silicones and other similar materials to the toner to enhance the print image and change it from a matt print finish to a glossy print finish. This has made laser black chemicals ineffective, and in any case, this method was and still is not good enough to give you a guaranteed good quality Photopolymer plate at the end of it. Expensive laser negative printers like the Xante work to some extent but still not as good as film negatives.
2. Inkjet film negatives are primarily targeted at the silkscreen printing sector as the black density is not as critical because of the thickness of the light sensitive coating on the mesh is very thin and so will cure very quickly. You can use a RIP and produce a much better quality image and expensive inkjet printers will also work to some extent but again not as good as film negatives.
3. Laser foil negatives are a hybrid where you laser print onto a clear transparent film and using a very good quality heat and speed controllable laminator apply a special black foil onto the laser printed film and then peel off to leave behind a negative. This system can be used in a few different ways and can produce a good quality negative, but can be a little weak with fine and small point size text and graphics, and you could also have issues with very large solid areas.
4. Photographic negatives are by far the best way to make negatives. The negatives made using this method can be used multiple times over many years. If you have an image-setter, then on completion of your artwork, just image a negative and then develop. The next option would be to print your design and image onto a negative on a process camera and the develop (Dark Room Required). Both the above requires expensive equipment to make, so the third option is the one we recommend. This method was developed by our sister company Polydiam Industries Limited close to 40 years ago and is still the best system for making negatives in-house. All you need, is to use the machine you are going to use, to exposure your Photopolymer plates to make your negatives, i.e. a machine with UVA florescent lamps in them. Print artwork onto our artwork sheet then place a sheet or piece of negative film on top, and in vacuum or under pressure using foam, exposure to UV light for around 5 seconds and then dish develop with a diluted developer and then a diluted fixer and you are ready to make plates. The whole process of making a photographic negatives take 2 to 3 minutes with no darkroom required. Windows must be covered and you can work in normal subdued light, away from very bright light. We can supplied full instructions and guidance with regards to how to make the negatives, the type of equipment and or attachments you may require.
Sheet photopolymer plates require a high degree of crosslinking and the Photopolymer layer is substantially thicker than for example Offset/Litho Printing Plate, Silk screens. If your negative is not opaque enough you will be letting light seep through onto your non-image areas and hardening them.
We at uEmboss supply Laser Film, Inkjet Film, Laser Foil system and Contact Film and so are a one stop shop for all your negative materials. We are not a box shifter, we support all our products and provide our customers with instructions of use and technical support so you would be actually able to use the materials. We can also help you select the best system for you, based on the information you provide.