Canon Kabushiki Kaisha

Chikanobu Ikeda

Yasushi Miura

Makoto Aoki

Shigeru Watanabe

Hiroyuki Kuriyama

Masashi Shimizu

Toshiaki Mabuchi

Tokihide Ebata

Katsuhiro Watanabe

Yoshiko Miyashita

Takeshi Irizawa

Tomoyuki Kawana

Hiroyuki Miyake

A printing apparatus and an ink-discharge status detection method which perform appropriate print control by detecting discharge failure with a simple construction, without reducing the printing speed. The apparatus, to which the method is applied, performs test ink discharge from a part of nozzles of a printhead while scanning the printhead, and detects ink discharge statuses of the nozzles of the printhead by using a photosensor in an area between the home position of the printhead and a position outside of an effective printing area. In next detection, nozzles different from those used in the previous test ink discharge are used for performing test ink discharge, and discharge statuses are detected. Discharge statuses of all the nozzles are detected in forward and backward scannings or a plurality of scannings.

Printing apparatus and ink-discharge status detection method

A printing apparatus and a print control method which detect a defective printing element in operation failure status while reciprocate-scanning a printhead, and perform appropriate print control such as complementary printing on an unprinted portion by the defective printing element, without reducing the printing speed. An apparatus, to which the method is applied, has a photosensor to detect ink discharge statuses of a plurality of nozzles of a printhead which is provided between a home position of the printhead and the outside of an effective printing area where image printing is to be made. While the printhead is scanned, test ink discharge is performed at the position of the photosensor and the ink discharge statuses of the nozzles are detected by the photosensor A corrector analyzes the operation statuses of the nozzles of the printhead based on the results of detection in a real time manner. A CPU performs print control based on the results of analysis.

Printing apparatus and print method

In an ink-jet printing apparatus, upon turning on the power source of the printing apparatus, a stirring operation of ink in the main tank is performed for a given period of time, and during subsequent printing operation, the stirring operation in the main tank is performed for the given period at every predetermined elapsed time period. By this, the printing operation for a long period can be performed employing ink having a water insoluble dye without causing a problem of admixing of bubble or so forth caused by stirring of the ink in the main tank.

Ink-jet printing apparatus

An ink-jet printing apparatus restricts fluctuation of the printing density due to coagulation and settling of a coloring agent in a water based ink, in which a water insoluble coloring agent or a coloring agent having low water solubility is dispersed. By this, movement of the ink caused due to difference of specific gravity caused by coagulation of the coloring agent or so forth in an upper passage to a lower passage can be restricted to successfully prevent increasing of difference of ink density.

In an ink-jet printing apparatus, upon turning on the power source of the printing apparatus, a stirring operation of ink in the main tank is performed for a given period of time, and during sequent printing operation, the stirring operation in the main tank is performed for the give period at every predetermined elapsed time. By this, the printing operation for a long period can be performed employing ink having a water insoluble dye without causing a problem of admixing of bubble or so forth caused by stirring of the ink in the main tank.

An ink-jet printing apparatus restricts fluctuation of the printing density due to coagulation and settle out coloring agent employing a water based ink, in which a water insoluble coloring agent or the coloring agent having low water solubility is dispersed. By this, movement of the ink caused due to difference of specific gravity caused by coagulation of the coloring agent or so forth in an upper passage, to a lower passage can be restricted to successfully prevent increasing of difference of ink density.

Growing community of inventors

Tokyo, Japan

Chikanobu Ikeda