BEFORE OFFSET PRINTING

• No solid area where toner will be applied.
  Background printing or colour washing should have a maximum halftone value of 15%. Full ink coverage on the reverse can also cause bad toner adhesion.
• Under colour removal (UCR).
  High ink density may cause offsetting and increases ink drying time.
• A4 fibre orientation - long grain.
  The best runnability for laser printing can only be guaranteed for A4 long grain.
  This is also recommended by all office machinery suppliers.
• For layouts with small printed areas and low ink consumption add outside the layout at the edge additional printed bars/solid areas.
  Low ink consumption affects the ink-water-balance, strong emulgation of the ink, this is affecting drying process of the ink and reduces printing quality.
• Paper acclimatisation at 18-24°C and 30-55% RH
  Cold paper will pick-up moisture immediately after unwrapping from a humid environment, causing waviness at the paper edges and leading to a low flatness with curls and jams.
• Unwrap the required amount of paper shortly before use.
  Pre-Print papers have 30-35% relative humidity which is lower compared to the offset papers (40-45%). Ream wrapper and plastic cover protect the pre-print paper from moisture pick-up.

DURING OFFSET PRINTING

• Use special laser printing inks
  Using special inks avoids bad odours after fusing in laser printing.
  If non-specialised offset inks are used, ink set-off may appear on transport rollers and belts within the office machinery.
• Minimum fountain solution 4,5 - 5,5pH
  Too much dampening during offset printing causes waviness.
  A too low pH-value (too acid) increases the ink drying time.
• No anti-set-off powder required
  Anti-set-off powder can melt at toner fusing temperature and causes contamination of the fixation unit, dusting in the office machinery and jams.
• Moisture protection required after printing prior to cutting
  To avoid moisture pick-up and waviness especially in the summer time and if drying process takes place in the night, protect the stack with the wrapped plastic.

AFTER OFFSET PRINTING

• Use sharp blades to cut the paper to final size.
  Clean cut edges will avoid blocking of sheets and feeding problems. Cutting dust and debris will contaminate the office machinery.
• Avoid moisture pick-up prior to laser printing.
  Protect and store printed products (letterheads) in moisture-poof wrapping material.
• Protect remaining paper on bulk pallet until it is next required.
  Protect remaining paper with moisture-proof material like plastic.