Certain examples relate to mixing and/or supply cartridges for printing apparatus. One example implementation includes a reservoir to receive printing material from a printing apparatus and to return the received printing material to the printing apparatus. A storage medium stores a reservoir printing material level parameter indicative of the amount of printing material in the reservoir; a recirculation cycle counter indicative of the number of recirculation events experienced by the cartridge; a maximum recirculation cycle parameter indicative of the maximum number of recirculation events that may be experienced by the cartridge.

A system for detecting a filling level in a printing fluid waste container comprises a waste container that collects excess printing fluid in a reservoir, and an optical sensor unit that detects a filling level of the reservoir on a filling reference surface.

An inkjet recording apparatus includes: an inkjet head that has nozzles that discharge ink; a pressure applicator that applies an external force to the ink; a hardware processor; and a flow detector. The hardware processor controls a maintenance mode in which the pressure applicator applies the external force to the ink and forces the ink to be discharged from the nozzles. The flow detector detects flow of the ink discharged from the nozzles by the pressure applicator during the maintenance mode. The hardware processor then determines an ink discharge status at the nozzles based on a detection result by the flow detector.

An inkjet recording apparatus includes: an inkjet head that has nozzles that discharge ink; a pressure applicator that applies an external force to the ink; a hardware processor; and a flow detector. The hardware processor controls a maintenance mode in which the pressure applicator applies the external force to the ink and forces the ink to be discharged from the nozzles. The flow detector detects flow of the ink discharged from the nozzles by the pressure applicator during the maintenance mode. The hardware processor then determines an ink discharge status at the nozzles based on a detection result by the flow detector.

A method for operating a printhead of a continuous inkjet printer comprising: producing at least one ink jet in a cavity of the print head; electrostatically separating drops or sections of one or more of the jet intended for printing from drops or sections that do not serve for printing; exiting from the cavity drops or sections of ink intended for printing, through a slot open on the outside of the cavity; and circulating at least one flow of air along the outlet slot of the cavity in a direction essentially perpendicular to at least one jet of ink emitted by the printhead and intended for printing. The air having a water vapor pressure lower than the water vapor pressure defined by 100% relative humidity at the coldest temperature of the printer.

A method for operating a printhead of a continuous inkjet printer comprising: producing at least one ink jet in a cavity of the print head; electrostatically separating drops or sections of one or more of the jet intended for printing from drops or sections that do not serve for printing; exiting from the cavity drops or sections of ink intended for printing, through a slot open on the outside of the cavity; and circulating at least one flow of air along the outlet slot of the cavity in a direction essentially perpendicular to at least one jet of ink emitted by the printhead and intended for printing. The air having a water vapor pressure lower than the water vapor pressure defined by 100% relative humidity at the coldest temperature of the printer.

A transportation portion includes an apparatus body, a cover, first and second path formation portions, and a movement portion. The apparatus body has a transportation path including a downward path and an upward path having portions located at the same level in the Z direction. The cover covers and uncovers the transportation path. The first path formation portion is movable to a first position and to a second position. The second path formation portion defines the upward path and defines the downward path with the first path formation portion. The movement portion moves the first path formation portion in response to opening or closing of the cover. The first path formation portion is positioned in a movement area during a closed state. The movement portion moves the first path formation portion to the second position when the cover is opened and to the first position when the cover is closed.

A transportation portion includes an apparatus body, a cover, first and second path formation portions, and a movement portion. The apparatus body has a transportation path including a downward path and an upward path having portions located at the same level in the Z direction. The cover covers and uncovers the transportation path. The first path formation portion is movable to a first position and to a second position. The second path formation portion defines the upward path and defines the downward path with the first path formation portion. The movement portion moves the first path formation portion in response to opening or closing of the cover. The first path formation portion is positioned in a movement area during a closed state. The movement portion moves the first path formation portion to the second position when the cover is opened and to the first position when the cover is closed.

A liquid absorber includes a container that has an opening and that recovers liquid and a first absorbing unit that is constituted by an aggregate of porous absorbing body blocks and that is housed in the container such that a gap exists between the porous absorbing body blocks. The porous absorbing body blocks have a density of 0.05 [g/cm.sup.3] or more and 0.50 [g/cm.sup.3] or less.

A liquid absorber includes a container that has an opening and that recovers liquid and a first absorbing unit that is constituted by an aggregate of porous absorbing body blocks and that is housed in the container such that a gap exists between the porous absorbing body blocks. The porous absorbing body blocks have a density of 0.05 [g/cm.sup.3] or more and 0.50 [g/cm.sup.3] or less.