Abstract: It is an object of the present invention to provide an ink jet printing apparatus which sufficiently heats a head even in a low-temperature environment, which enables a proper image to be printed by stably ejecting ink, and which can be inexpensively and simply constructed. According to the present invention, if the detected temperature of a printhead is lower than a first heating threshold temperature higher than the first heating threshold, a heating mode in which the printhead can be heated is set before a printing operation. Further, when the heating mode is set and the detected temperature of the printhead is lower than the heating threshold temperature, a heating unit heats the printhead. Consequently, even in a low-temperature environment, the heating operation keeps ink good and suitable for printing.

Abstract: Deterioration in image quality is caused by deviation in dot forming positions between rasters in the case of carrying out printing of adjoining two rasters. The rasters are printed by two columns of ejection openings array disposed on an ink-jet head. To suppress image quailty deterioration, the two columns of ejection openings are shifted from each other by a half of a pitch at which the ejection openings are arranged in the column. When allocating input image data quantized into multi-valued levels to 2×2 dot array as pseudo half-tone processing before printing, the mutually different plural dot arrangements are applied concerning each level of the input image data, and the plural dot arrangements are cyclically changed in the main scanning direction according to predetermined rules, and also equalization processing for equalizing the number of said adjoining the two raster dots is properly performed in the one cycle.

Abstract: The present invention provides a method of printing a high quality color image with no color variations at high speed. For this purpose, this invention arranges in a main scan direction a plurality of print heads that eject different color inks, and reciprocally moves each of the print heads to perform a multipass printing in which a print operation is executed in both the forward and backward passes. During the multipass printing, the print duties of the print heads are set by mask patterns. Each of the mask patterns divides the print duty setting area for each nozzle group of each head into subdivided areas, sets the print duties of the subdivided areas to values different from each other and sets the print duties of the print heads to different values.

Abstract: To make it possible to print a smooth image without color irregularity at a high speed by a printing apparatus using a color ink-jet head provided with plural arrays of ink ejection openings side by side in the direction of the main scanning corresponding to different color inks, moving this head to scan reciprocally, and also adopting a multi-pass printing method for divided printing on a certain area by scanning at plural times with the color ink-jet head. In the multi-pass printing using the color ink-jet head, an ink firstly landed on a certain area determines a prioritized color influential on the color tone. Moreover, a printing medium is largely covered by a first two-pass printings. Namely, if it is possible to suppress the color irregularity in the first two passes, a harmful influence on a whole image by the color irregularity can remarkably reduced, therefore, the first pass data printing ratio to the area is set smaller than that of the second pass and thereafter.

Abstract: The present invention reduce the granularity of the dots for the entire density range by optimally setting formation amounts of a low-density dot and of a high-density dot per unit area. For this purpose, the formation amounts of the low-density dot and of the high-density dot in accordance with the density level are decided in such a way that as the density level rises, the formation amount of the low-density dot is gradually increased up to a first peak amount (200%) and, after reaching the first peak, gradually decreased, and in a range of density levels higher than a predetermined density level at which the low-density dot is formed to a specified amount (200%), as the density level rises, the formation amount of the high-density dot is gradually increased up to a second peak amount (100%) smaller than the first peak amount.

Abstract: A leather coloring process for carrying out coloring on a natural leather, or a natural leather which has been subjected to degreasing. The coloring process is accomplished by ink-jet coloring on at least a partial area of the natural leather.

Abstract: A color ink-jet head, having plural arrays of nozzles side by side in a main scan direction corresponding to different color inks, is moved to scan reciprocally. In a multi-pass recording for divided recording on an area by scanning at plural times with the head, an ink firstly landed on recording of the area determines a prioritized color influential on the color tone. Moreover, a printing medium is largely covered by the recording of first two passes. A harmful influence on a whole image by the color irregularity can reduced by suppressing the color irregularity in the two passes, therefore, the data recording ratio of the first pass to the area is set smaller than that of the second pass and thereafter. Further, for such the control, a pseudo periodical masking data arranging record prohibiting pixels and record permitting pixels in a visually agreeable state is introduced.

Abstract: The present invention is designed to make uniform frequencies with which individual recording elements of an multihead are used in a recording apparatus for performing gray scale recording by controlling a number of dots recorded in a unit area. A gray scale pattern used to display gray scale is a pattern in which a plurality of blocks each comprising a dot concentration type gray scale pattern having a size smaller than that of the gray scale pattern is dispersed. The maximum difference between numbers of times the recording elements in the range of the gray scale pattern are used can be restricted within twice, and individual nozzles can be used uniformly. Consequently, imbalance of changes in the recording elements with time, caused by the differences between the frequencies with which the recording elements are used, can be restricted, thus restricting irregularities on an image.

Abstract: The present invention provides a printing apparatus and method that can prevent the image grade from lowering. A print head is provided with a plurality of printing elements to print dots on N adjacent rasters and dots on M adjacent columns under different conditions by causing the print heads perform a plurality of (P) main-scanning operations in a main-scanning direction and transporting a printing medium at least once in a sub-scanning direction. A plurality of dot arrangement patterns used for the same level of image data are periodically changed. The plurality of dot arrangement patterns are such that within each period when the patterns are repeatedly used, the number of dots formed in each of said N rasters are equalized, whereas the number of dots formed in each of said M columns are equalized.

Abstract: This invention relates to an ink-jet printer equipped with an ink-jet printhead and a control method and apparatus for the ink-jet printer. The printhead incorporates an EEPROM storing head information including the ink discharge amount characteristics of the printhead. The head information stored in this EEPROM is transmitted from the ink-jet printer having the printhead to the printer driver of a host computer. The printer driver then selects a gamma correction table in accordance with the head information. In this case, a gamma correction table is selected from a plurality of gamma correction tables in which pieces of correction information which make print densities uniform are stored in correspondence with ink discharge amounts. This table also includes correction data for correcting an increase in ink discharge amount to prevent beading due to an increase in ink discharge amount with a rise in the temperature of the printhead.

Abstract: An ink-jet printing apparatus for printing an image based on image information on a printing medium by relatively moving an ink-jet printhead and the printing apparatus detects the temperature of the ink-jet printhead by using a head temperature detection unit and outputs it to a driving frequency determination unit. The driving frequency determination unit acquires temperature information in units of pages of image information or predetermined image areas. If the acquired temperature is equal to or higher than a predetermined temperature, the driving frequency of the ink-jet printhead is decreased when a predetermined unit of the image information is printed.

Abstract: By performing printing by a reduced number of main scanning times and by a bind pitch of a period which is imperceptible to human vision, a printing apparatus and a printing method for forming an image of visually imperceptible banding artifacts is provided. For this purpose, in a printing apparatus wherein a printing head is scanned for a plurality of times in a main scanning direction and at each scanning the printing head is divided into a plurality of blocks and printing is made to a region corresponding to each of the blocks by multi-scanning printing, the region is formed by printing one divided region in each of the plurality of scans in a transporting direction.

Abstract: A liquid container for a liquid jet recording apparatus comprises a first chamber containing negative pressure producing material and having a liquid outlet connectable to a liquid jet head to supply liquid from the container to the liquid jet head and an air vent for allowing ambient air into the container, wherein the liquid outlet is provided in a bottom portion of the first chamber. A second chamber communicates with the first chamber by a communication path and is substantially hermetically sealed. A wall extends upwardly from the communication path of the first chamber. An ambient air introducing path is provided for between the wall and the negative pressure producing material extending from a point partly up the wall toward the communication path for introducing ambient air into the second chamber.

Abstract: An ink-jet printing process using an ink containing a dye having an ionicity. The process includes the steps of: providing a cloth containing (a) a substance having an ionicity opposite to the ionicity of the dye and a molecular weight of from 100 to 700, or a nonionic surfactant having a molecular weight of from 100 to 700 and an H.L.B. of from 7 to 15, and (b) a polymeric substance having an ionicity opposite to the ionicity of the dye and a molecular weight of from 2,000 to 200,000; printing on the cloth with the ink; washing the cloth after printing; and drying the cloth.

Abstract: When an image is sensed by a digital camera, image additional information as the image sensing conditions is stored together with the sensed image information. Also, information unique to that digital camera is stored together with the image additional information. The digital camera is connected to a printer by, e.g., an IEEE1394 I/F. The printer stores printing control information as various combinations of unique information such as its printing method, the types of ink, paper, and the like, print quality and print speed, and processing technique such as masking. In response to a print instruction, the printer reads the image information ad image additional information from the digital camera, and selects the printing control information in accordance with the read information and the set printing mode. The printer prints an image using the selected printing control information.

Abstract: When an image is sensed by a digital camera, image additional information as image sensing conditions is stored together with the sensed image information. Also, information unique to that digital camera is stored together with the image additional information. The digital camera is connected to a printer by, e.g., an IEEE1394 I/F. The printer stores printing control information as various combinations of unique information such as its printing method, the types of ink, the paper, and the like, the print quality and the print speed, and the processing technique, such as masking. In response to a print instruction, the printer reads the image information and image additional information from the digital camera, and selects the printing control information in accordance with the read information and the set printing mode. The printer prints an image using the selected printing control information.

Abstract: Disclosed herein is an ink-jet printing cloth suitable for use in printing with inks each containing a dye having an ionicity, wherein a substance not having the same ionicity as that of the dye and having a molecular weight lower than 1,000, and a polymeric substance having an ionicity opposite to that of the dye and a molecular weight higher than 2,000 are applied to the cloth.

Abstract: Per every one printing scan of a head, a printing data to be printed by the corresponding scan is divided into L in a scanning direction (lateral direction) and N in a paper feeding direction (longitudinal direction. Concerning each counting blocks identified by l and number of driving rln is counted. Then, with respect to each l, rln are sequentially summed from n=1 to obtain Sl. At every time of summing for deriving Sl, judgment is made whether Sl is greater than a predetermined value R determined in association with a power source capacity. When judgment is made that Sl is greater than R, printing of a printing data corresponding to the counting blocks of 1 to (n−1) with respect to n−1 which is one smaller value that the value n of the counting block upon judgment that Sl is greater than R, is performed, and then paper feeding is performed for the corresponding counting blocks. Thus, lowering of throughput can be restricted with optimally using the power source capacity of the apparatus.

Abstract: Ink which contains surfactant in the amount of not exceeding the critical micelle concentration in the ink but exceeding the critical micelle concentration in purified water, is filled into a cartridge, comprising a first chamber which encloses a negative pressure producing material, and a second chamber in communication with said first chamber only through a narrow passage Then, said ink is supplied to ink jet head and printed.

Abstract: In the present invention, upon printing of an image on a printing medium by ejecting an ink for a treatment liquid ejected on the printing medium, by scanning the printing medium, a number of scan for the same region of the printing medium is judged, and ejection from a printing head is performed by variably setting the ejection amount of the treatment liquid in one scan by varying ratio of dots to be ejected versus all dots on the printing medium. Thus, deposition of mist or rebounded droplets on an ejection surface of an ink ejecting portion of the printing head can be avoided. By the present invention, pollution of the ejection surface of the printing head is avoided and thus reliability of ejection of the printing head is maintained.