Frames - It is critical that the mesh releases from the ink film immediately after the squeegee passes, so high tension stretching (> 20N/cm) onto a rigid metal frame is required. CPS Screen Adhesive will hold the high mesh tensions that are required and will not slip when exposed to CPS Ink Cleaning solvents.
Mesh - Always use the highest quality polyester mesh for Fototex printing, as even minor variations in weave quality can show up in the print. Select a 90 threads/cm monofilament PET mesh for Fototex UV printing and 100–150 threads/cm for Fototex N. The use of a finer mesh can give rise to variations in gloss levels as the matting agents in the Fototex lacquer are filtered out by the fine mesh. Conversely, if too coarse a mesh is used this will lead to a thick print that may not cure fully.
Printing – In order to get the best adhesion of the Fototex lacquer to Autoflex, the sheets must be printed within 48 hours (ideally within 24 hrs) after removing them from the original packaging. N.B Autoflex PC MUST be printed with Fototex within 24 hours. If Autoflex is left unwrapped, the surface will slowly react with air and light which reduces the adhesion between Fototex and the hard coat surface. Therefore, the Fototex texture must always be printed first, or second in the print sequence. Once correctly cured, the adhesion of the Fototex lacquer is permanent and will not deteriorate.
IMPORTANT: Only handle Fototex lacquer in a UV-free environment and it is critical to thoroughly stir Fototex for a minimum of 2 minutes prior to printing.
Print using a very high quality 70-90 shore Polyurethane squeegee, as even the smallest nick in the squeegee blade will show up in the print. It is also recommended to set both the squeegee and flood stroke start/stop positions at least 20cms beyond the image area to allow the lacquer to settle before reaching the critical print area.
The recommended texture thickness is 20–25µ for Fototex N and 30-40µ for Fototex UV products. Always use a micrometer to accurately measure the texture thickness.
Dust is impossible to remove from the cured Fototex print, therefore prevention is always better than contamination!
- A clean working environment is essential for printing quality textured finishes
- Remove any contamination from the dry screen prior to printing with a low tack roller
- If the print room is not a ‘clean room’, then create a cleaner environment around the press by curtaining. This will also enable you to increase the relative humidity (RH) to reduce static build up during printing. An extractor hood will be required for local exhaust
- The operators should wear clean room clothing
- Always clean the substrate prior to printing using a low tack roller or machine
- Try to restrict personnel movement in the area during printing
- Place tack mats around the press
- Cover the screen during stoppages or remove the lacquer
- Never return unused lacquer to the pot
Curing - Fototex UV can be cured on most conventional high intensity UV curing units. A curing dose of 500–1,000 mj/cm² is required.
Fototex N requires UV curing in a Nitrogen blanket such as the Linde system.
Ink cleaning On Press: If the screen needs to be cleaned during printing use CPS Screen Opener 511 or CPS Screen Cleaner K3x and allow the mesh to dry out completely before recommencing printing.
Ink cleaning Archiving: If the screen is to be archived for reuse, it can be cleaned with CPS Screen Opener 511 (Flash point 44°C), CPS Screen Cleaner K3x (Flash point 43°C) or CPS Screen Cleaner Vx (Flash point 63°C), paying particular attention not to damage the stencil.
Ink Cleaning Recirculation & Cleaning Machine: If using a recirculation unit or a cleaning machine, then CPS Screen Wash V3, CPS Screen Wash A6, CPS Aquawash 829, CPS Bio Plus Screen Wash G or CPS Screen Wash A7 shoudl be used.
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Name: William Shorter
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