2.3 Ink Metering & Anilox rolls Flashcards
ink metering refers to
applying correct ink film thickness to plate
too think ink film can cause
low density, weak colour
too thick ink film can cause
high density, dark colour
slow drying
blocking
poor ink trap in overprint areas
ink metering is controlled by
the ink
anilox roll
metering method
What must have the same surface speed
Plate - substrate
Anilox roll - plate
What are the three ink metering methods
Fountain roll doctoring (two roll method)
Reverse angle doctor blade
Chambered doctor blade
Describe Fountain roll doctoring
Hard rubber roller transfer ink from pan to plate
Roll may turn at same speed or slower to provide wiping action
Describe Reverse angle doctor blade
Metering roll doesn’t touch anilox
Metering roll only floods anilox with ink
Describe Chambered doctor blade
Consists of backing plate blade and reverse doctor blade
Metering is done by the reverse angle blade
When mechanically engraved anilox rolls are coated with ceramic, max lpi is
220 lpi
All mechanically engraved anilox rolls have a _______ degree angle
45
Max lpi for laser engraved anilox roll are
1200-1500lpi
Anilox cell angle for newspaper printing is _______ and for coating applications it’s __________.
45
30
Lower the cell volume =
Larger the area will be covered by ink
Cell volume to low….anilox roll should be repaired …..T or F?
True
