Offset Litho Printing
All PCL grades can be conventionally litho printed.
The following guidelines are given in good faith to assist the litho printer
unused to printing labels or synthetic materials.
Polyester grades
Use fully oxidising inks specifically formulated for polyester materials (standard paper grade oxidising inks are not suitable)
• Ensure all traces of oil based inks and varnishes are removed from the ink delivery system
• Run press as dry as possible as excessive damping will retard drying
• Check suitability of product for printed matter and process e.g. images achieved using 1 print station on paper may require 2 print stations for polyester grades
• Run 4 colour work in one pass. It is not advisable to run 4 colour work on polyesters using a single or 2 colour press
• Avoid excessive use of spray powder- use a LIGHT coating ONLY. Do NOT use dissolvable spray powder as this will affect the keying process
• If material is to be subsequently laser or copier printed ensure the correct laser compatible inks are used and the ink has completely cured (at least 7 days)
Paper grades
Use fully oxidising inks where necessary
• Use formulated (not reduced) extra low tack inks and a hard blanket for printing pre die cut labels in order to reduce the ‘suction’ effect.
• If materials are to be over printed by laser or copier ensure that the correct heat stable litho inks are used
• Always re-wrap in polythene bags and box any printed stock to be subsequently over printed by laser or copier
• Leave pre-litho printed stock for 4 - 5 days before laser/ copier printing
• Reduce the potential for static by loading polyesters sheet by sheet into the feed stack. This introduces a layer of air between each sheet and helps prevent static