C6C CARTRIDGE FORMULATION
TEXT BLACK PIGMENT PGI-220BK C1128P
CYAN CLI-221C PC226-C
MAGENTA CLI-221M PC226-M
YELLOW CLI-221Y PC226-Y
PHOTOBLACK CLI-221BK PC226-BK
GRAY CLI-221GY PC226-GY
PGI-220BK ink is text black pigment used solely when printing on plain or copy paper. The PG at the start of the cartridge model number is shortform for PiGment. Text black pigment ink is preferred for sharper text printing, has less bleed on papers, is waterproof and will not fade. Text black pigment ink is slightly slightly costlier than dye ink.

All other CLI-221 colors used in this printer are dye inks.  The photoblack black  ink is used when printing photos on glossy paper.

If the printer has a duplex mode or two sided printing feature, photoblack dye is used on one side and text black pigment on the other.

Because of the way an inkjet printer works, a small quantity of color ink is still used during maintenance functions even if you print mainly text.
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