Abstract: Provided are an inkjet printing apparatus and inkjet printing method that can, regardless of an ejection frequency of a print head, stabilize density of an image expressed on a print medium. For this purpose, an ink concentration integrated value is obtained according to the ejection history of each nozzle so as to be increased by data indicating non-ejection of the nozzle or decreased by data indicating ejection. Then, image data on the target pixel is corrected such that density of the target pixel is further reduced as the pixel is subjected to printing by a nozzle having a higher ink concentration integrated value.

Abstract: Adequate correction processing is performed on image data based on the degree of ink concentration that occurs even. An image processing apparatus having: acquisition unit for acquiring multi-value image data and a first parameter related to the degree of concentration of ink; first generation unit for generating corrected data by correcting the multi-value data that is to be printed for the first pixel based on the multi-value data that is to printed in the first pixel and a first parameter; and second generation unit for generating the first parameter and a second parameter that indicates the degree of ink concentration of the plurality of nozzles when printing a second pixel that is printed by the nozzles next to the first pixel.

Abstract: A printing device using a print head ejecting ink from a plurality of nozzles to print ink dots of a plurality of dot diameters, includes a print-characteristic acquisition unit obtaining print characteristic information on dot diameters of ink dots to be printed per each predetermined portion of the plurality of nozzles, a distribution ratio determination unit determining a distribution ratio for distributing image data to the predetermined portions of the plurality of nozzles based on the information, a dot print position determination unit quantizing the image data to determine a dot print position based on the image data and sizes and an array of thresholds; and a plurality of masks based on dot distribution order determined according to the distribution ratio, distributing printing of each of the ink dots of the plurality of dot diameters to the dot print position determined by the dot print position determination unit.

Abstract: A large and small dot distribution pattern is generated, for each chip, according to a large and small dot distribution ratio and ejection failure nozzle information. In doing so, a bias of large and small dot distribution ratio at a nozzle position including an ejection failure nozzle is set to be smaller than that at a nozzle position that does not including an ejection failure nozzle. Then, dot data to be printed by the ejection failure nozzle is equally distributed to large dot nozzles that can eject normally and small dot nozzles. By such a configuration, even if a plurality of printing chips have different printing characteristics, ejection failure compensation processing is performed to minimize image degradation caused by an unexpected ejection failure and an average ejection volume of each of the chips converge on a fixed target ejection volume, which leads to reduction of density unevenness among the chips.

Abstract: An ink jet printing apparatus comprises a distributing unit configured to distribute print data for printing dot into data used for printing by first printing elements provided in a print head and data used for printing by second printing elements provided in the same print head, and a determining unit configured to, for the data used for printing by the respective parts of the printing element arrays of each of first and second print heads which have the overlapped print regions, determine a ratio between amount of the data used for printing by a combination of the first and second printing element arrays in the first print head and a combination of the first and second printing element arrays in the second print head.

Abstract: A low toxicity, corrosion and scale inhibiting composition for use in recirculating aqueous systems, e.g. in heat exchangers, comprises from about 3-1,000 parts by weight of molybdate, from about 0.5-1,000 parts by weight of an organic cationic or non-ionic surfactant, from about 0.3-1,000 parts by weight of a water soluble polyphosphate and from about 0.05-500 parts by weight of an azole, for example tolyltriazole. The composition is water soluble or water dispersible, and is effective in very small amounts (3-3,500 ppm) for corrosion control of metals such as carbon steel, copper and aluminum exposed to circulating water.