Filled With Ink; Ink Near-Empty/Ink Empty; Ink Cartridge Features; 4 ] Ink Cartridges - Brother DCP6690CW Service Manual

[ 4 ] Ink cartridges

Ink near-empty/Ink empty

Filled with ink

Disc valve S
Sensor actuator
Air
Ink empty sensor
Ink
(3_06)
Disc valve D

Ink cartridge features

This machine uses four ink cartridges: a black one and three color ones with a slightly lower
capacity. It features horizontal insertion in the ink refill base over plastic needles.
Each cartridge has two ports: one supplying the ink for printing and another intaking air to
replace that ink. Both ports have a disc valve preventing ink leakage. When a cartridge is
mounted over the plastic needles in the ink refill base, these valves are opened to secure flow
paths for both the ink and the air.
These ink cartridges are single-use affairs. There is no provision for refilling them. The design
reduces environment load by using only burnable materials yielding no toxic substances.
Inks
"Removing air"
An earlier page explained how too much air in the ink risks air bubbles degrading ink-jet
performance. The manufacturing process prevents such air bubbles with a step, deaeration, that
removes air from the ink before injection into the cartridge. Vacuum packaging then prevents
air contamination during shipping and storage.
"Pigment-based ink"
This machine uses dye-based inks for colors and pigment-based ink for black. Using the
pigment-based black ink reduces fuzziness from print character outlines, boosts resolution for
black dots, and produces clearer images on plain paper.
For the pigment-based black ink and its dye-based color counterparts, this machine provides
separate head caps and individual vent unit drive mechanisms. Such special design measures
are necessary because any mixing of the two types triggers a chemical reaction producing
residue clogging head nozzles, filters, maintenance unit piping, and other components,
degrading print performance.
(Refer to Section 3.2.2.2, [ 6 ] for the ink cartridge capacities and the number of printable pages
per ink cartridge.)
3-20
Confidential