Patent ID: 7121641
Filing Date: 2006-10-17
Classification: B41J,G06K

Abstract:
1. A color ink-jet recording apparatus using a black recording head that ejects black ink on the basis of black image data and a color recording head that ejects color ink on the basis of color image data, the color ink permeating through a recording medium at a higher speed than the black ink, said apparatus comprising: control means for controlling scanning of the black recording head and of the color recording head relative to the recording medium such as to complete a record image in a predetermined recording area including pixels on the recording medium by causing each of the black recording head and the color recording head to perform N (N being an integer equal to or greater than 2) recording scans in the same pixel; data generating means, which, for each of the recording heads, generates image data for each of the N recording scans corresponding to the predetermined recording area, by using N mask patterns, for black image data corresponding to the N recording scans and N mask patterns for color image data corresponding to the N recording scans, so that black image data corresponding to the predetermined recording area are allotted to each of the N recording scans, and color image data corresponding to the predetermined recording area are allotted to each of the N the recording scans; and ink ejecting means for ejecting the black ink and the color ink from the black recording head and the color recording head during each of the recording scans on the basis of the data allotted to each of the recording scans by said generating means, wherein total allotment rate of the N mask patterns for the black image data is 100% and total allotment rate of the N mask patterns for the color image data is 100%, and an allotment rate of the mask pattern for the black image data used in a given one of the N recording scans is smaller than 100% and is greater than a reference allotment rate, the reference allotment rate being (100/N)%, and an allotment rate of the mask pattern for the color image data used in that one recording scan is greater than 0% and is smaller than the reference allotment rate, and an allotment rate of the mask pattern for the black image data used in another recording scan is greater than 0% and is smaller than the reference allotment rate, and an allotment rate of the mask pattern for the color image data used in the latter recording scan is smaller than 100% and greater than the reference allotment rate.