JP2005254518A - Inkjet recording apparatus and inkjet recording method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recording apparatus which can suppress the generation of boundary bleeding while the generation of density irregularities of a recording region such as a meshed part (uniform half tone region) recorded by black ink where a change rate of a recording duty is relatively small is reduced, and also which can record high-quality black characters and the like, and to provide an inkjet recording method. <P>SOLUTION: A region where color dots are to be formed and a recording region adjacent to the region are detected by a detection process E1013 for a color adjacent matrix. The recording region where the change rate of the recording duty of black dots is relatively small is detected by a detection process E1001 for a black uniform half tone matrix. Data for applying the color dots is generated on the basis of the detection information D1018 and D1009. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an ink jet recording apparatus and an ink jet recording method for performing recording using a recording head capable of discharging black ink and at least one color ink.

  Conventionally, an ink jet recording apparatus that performs recording on various recording media is capable of high-density and high-speed recording operations, and thus is widely applied as a printer as an output medium of various apparatuses, a portable printer, and the like. And it is commercialized.

  A general serial scan type ink jet recording apparatus includes a carriage on which a recording head and an ink tank as recording means are mounted, a conveying means for conveying a recording medium, and a control means for controlling them. . Then, an operation of serially scanning a recording head capable of ejecting ink droplets from a plurality of ejection openings in a direction (main scanning direction) orthogonal to the conveyance direction (sub-scanning direction) of the recording medium, and setting the recording medium to a recording width By repeating the operation of conveying the same amount, an image is recorded in the recording area of the recording medium. Such a recording method performs recording by ejecting ink onto a recording medium based on a recording signal, and is widely used as a quiet recording method at a low running cost. In recent years, a number of products using a plurality of colors of ink and applied to a color image recording apparatus have been put into practical use.

  Since the black ink used in such a color ink jet recording apparatus is frequently used for recording characters and the like, it is required to realize sharpness and high recording density of a recorded image. Therefore, a technique is known in which the penetrability of the black ink with respect to the recording medium is lowered to prevent the coloring material in the black ink from penetrating into the recording medium.

  On the other hand, the color inks other than the black ink are mixed with each other at the boundary portion of the ink application portion when two different color inks are applied adjacently on the recording medium, There is a possibility that a phenomenon (boundary bleeding) that deteriorates the recording quality of a color image may occur. In order to prevent this, a technique for increasing the permeability of the color ink to the recording medium and preventing the color inks from mixing on the surface of the recording medium is known (see, for example, Patent Document 1).

  However, when such a low permeability black ink and a high permeability color ink are used, the following two problems occur.

  First, although the color ink has high permeability, the fixing time is fast, whereas the black ink has low permeability, and thus the dry fixing time is long. Therefore, when continuous recording is performed on a plurality of pages of recording paper as a recording medium, after the previously recorded page is discharged, the next recorded page is superimposed on the page. When the paper is ejected, the black ink applied to the previous page is not completely dry, so the recording surface of the previous page and the back surface of the recording paper of the next page may become dirty and dirty. Such contamination on the recording surface and the back surface of the recording paper is referred to as “smear”. Such a problem becomes conspicuous as the recording speed increases.

  Second, since black ink has low permeability, bleeding (boundary bleeding) may occur in the boundary region between the black ink and the color ink application portion on the recording medium. This significantly reduces the recording quality of the color image.

  Conventionally, the following first to third measures have been taken as solutions for these two problems.

  The first countermeasure is a method using an ink fixing means such as a heat fixing device. By this method, it is possible to fix smear and boundary bleeding on the recording medium at high speed (see, for example, Patent Document 1). However, in this first measure, since the fixing means is provided, the apparatus is inevitably increased in size and cost. Further, in the serial printer, since the recording medium feeding operation is intermittent, there is a possibility that uneven feeding occurs when the recording medium is passed through the fixing device.

Next, the second countermeasure is a method of performing discharge waiting control of a recording sheet as a recording medium. This method pauses the start of recording on the second recording paper or records the image on the second recording paper until the ink is sufficiently dried after the image is recorded on the first recording paper. After that, the recording paper discharge operation is temporarily stopped. By this method, it is possible to suppress the occurrence of smear. However, this second countermeasure causes the throughput to be lowered because the recording medium is waiting to be discharged.
A third countermeasure is a method of applying color ink having high penetrability so as to overlap the black ink application region. By applying the black ink onto the paper surface to which the color ink has been applied, the black ink is easily fixed on the paper surface, and smear can be suppressed. Furthermore, boundary bleeding can be suppressed by using an ink set of a type in which black ink and color ink react and aggregate (see, for example, Patent Document 2). According to the countermeasure described in Patent Document 2, it is possible to suppress smear and boundary bleeding without causing an increase in the size of the apparatus and a decrease in throughput.

JP 7-47762 A Japanese Patent Laid-Open No. 2003-159827

  However, in the method described in Patent Document 2 described above, there is a possibility that a problem as shown in FIG. 28 may occur.

  That is, in Patent Document 2, as shown in FIG. 28, an area on a recording medium is divided into predetermined small detection areas, the dot density of black ink in each small detection area is detected, and the dot density is predetermined. Color ink is applied to the small detection area exceeding the threshold. More specifically, as shown in FIG. 28, when an image including a character portion, a shaded portion, and a solid portion recorded with black ink is recorded on a recording medium, the size of the small detection area is recorded. The detection matrix 1000 corresponding to is set as the matrices M1 to M5, and the dot density of the black ink in each matrix is detected. The character portion is a region where black dots are formed based on the character data 1001, the shaded portion is a uniform halftone region where black dots are formed based on the shaded data 1002, and the solid portion is solid data of Bk ink. This is an area where black dots are formed with high duty based on (Bk solid data) 1003. Since the dot density of the black ink is relatively low, the region including the matrices M1 to M3 is a region where no color dots are applied, that is, a non-overlapping region 1004 of color dots. In addition, since the dot density of the black ink is relatively high, the area including the matrices M4 and M5 is an area to which color dots are applied, that is, an overstrike area 1005 of color dots.

  As for the shaded portion, a region A1 (region including the matrix M3) where color dots are not overprinted and a region A2 (region including the matrix M4) where color dots are overprinted are mixed. Therefore, density unevenness may occur in the shaded portion. In particular, since the dot density of the black ink for recording the shaded portion is relatively low, the density and color tend to change depending on whether or not the color dots are overprinted, and density unevenness is likely to occur.

  Such density unevenness caused by the presence or absence of overprinting of color dots is not a problem that occurs only when the above-described configuration in which color dots are overprinted in the black high duty region is employed. For example, in order to suppress the boundary bleeding between black and color, a problem arises similarly in a configuration in which color dots are overprinted on black dots in a high duty area of the color.

  The present invention has been made in view of the above situation, and the density unevenness of a recording area where the degree of change in recording duty is relatively small, such as a shaded portion (uniform halftone area) recorded by black ink. An object of the present invention is to provide an ink jet recording apparatus and an ink jet recording method capable of suppressing the occurrence of black / color boundary bleeding while reducing the generation.

  The inkjet recording apparatus of the present invention uses a recording head capable of discharging black ink and at least one color ink, and based on black data for discharging the black ink and color data for discharging the color ink, In an inkjet recording apparatus for recording an image by forming black dots by the black ink and color dots by the color ink on a recording medium, color dots in a unit recording area on the recording medium based on the color data A first detection means for detecting a recording area in which the number of formations is equal to or greater than a first threshold and a recording area adjacent thereto as a first recording area, and black between adjacent unit recording areas based on the black data Second recording in which the difference in the number of dots formed is less than the second threshold value In the first recording area and the second recording area based on the black data corresponding to the first recording area and the black data corresponding to the second recording area. An application data generation unit that generates application data for applying the color dots to the image data; a recording color data generation unit that generates the recording color data by reflecting the application data in the color data; and the black data. And control means for performing recording by controlling the recording head based on the recording color data.

  The inkjet recording apparatus of the present invention uses a recording head capable of discharging black ink and at least one color ink, and based on black data for discharging the black ink and color data for discharging the color ink, In an ink jet recording apparatus for recording an image by forming black dots by the black ink and color dots by the color ink on a recording medium, information on the amount of color dots formed in a unit recording area is obtained based on the color data. And acquiring information relating to a relative difference in black dot formation amounts between adjacent unit recording areas based on the black data, and a first detection means for detecting a first recording area based on the information relating to the formation amount. , Information on the relative difference in the amount of formation And the second detection means for detecting the second recording area, the black data corresponding to the first recording area and the black data corresponding to the second recording area, An application data generation unit that generates application data for applying the color dots in the second recording area, and a recording color data generation unit that generates the recording color data by reflecting the application data in the color data. And control means for performing recording by controlling the recording head based on the black data and the recording color data.

  The inkjet recording method of the present invention uses a recording head capable of ejecting black ink and at least one color ink, and based on black data for ejecting the black ink and color data for ejecting the color ink, In an inkjet recording method for recording an image by forming black dots by the black ink and color dots by the color ink on a recording medium, and a recording area in which the color dots are formed and adjacent thereto based on the color data A recording area to be detected is detected as a first recording area, a second recording area having a relatively small change rate of the recording duty of the black dots is detected based on the black data, and the black corresponding to the first recording area is detected. Corresponding to the data and the second recording area Based on the rack data, generation data for applying the color dots in the first recording area and the second recording area is generated, and the color data is recorded by reflecting the application data in the color data. And recording is performed by controlling the recording head based on the black data and the recording color data.

  According to the present invention, boundary bleeding is performed by assigning color dots to a region where color dots are formed and a recording region adjacent to the region, and a region where the change degree of the recording duty of black dots is relatively small. In addition to preventing or reducing the occurrence of, and preventing or reducing the density unevenness of an image (for example, a shaded pattern) where a relatively large density unevenness is likely to occur between the portion to which the color dot is applied and the portion to which the color dot is not applied, Recording quality can be improved. In addition, a sharp black image can be recorded without adding color dots to a recording region such as a black character.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following embodiment is an application example for an ink jet recording type recording apparatus.
[First embodiment]
FIGS. 25 to 27 are diagrams for explaining a configuration example of an ink jet recording apparatus to which the present invention is applicable, and FIGS. 1 to 9 are diagrams for explaining a first embodiment of the present invention.

(Configuration example of recording device)
FIG. 25 is a schematic perspective view showing a configuration example of a color inkjet recording apparatus to which the present invention can be applied.
In this figure, 202 is four ink cartridges. These include an ink tank in which four colors of ink (black (Bk), cyan (C), magenta (M), and yellow (Y)) are respectively placed, and a recording head 201 that can discharge these inks. It is configured. The configuration of the recording head 201 will be described later. Reference numeral 103 denotes a paper feed roller, which rotates in the direction of the arrow in the figure while suppressing the recording paper 107 as a recording medium together with the auxiliary roller 104, and feeds the recording paper 107 in the arrow B direction (sub-scanning direction). Do. Similar to these rollers 103 and 104, the roller 105 also serves to hold down the recording paper 107. A carriage 106 has four ink cartridges 202 mounted thereon and moves in the main scanning direction indicated by an arrow A together with the ink cartridges 202. The carriage 106 is controlled to stand by at the position (home position) h of the dotted line in the figure when the recording apparatus is not recording or when the recovery operation of the recording head is performed.

  Before the start of recording, the carriage 106 is positioned at the home position h. In response to the recording start command, the recording element provided in the recording head 201 is driven to eject ink while moving the carriage 106 in the main scanning direction indicated by the arrow A, thereby recording corresponding to the recording width of the recording head 201. Recording is performed in an area on the sheet 107. When the recording scan to the end of the recording area on the recording paper 107 is completed along the main scanning direction of the carriage 106, the carriage 106 returns to the original home position h and performs the recording scanning in the main scanning direction again. After the previous recording scan is completed and before the next recording scan is started, the paper feed roller 103 rotates in the direction of the arrow to feed the recording paper 107 in the backward scanning direction by the required width. By repeating such recording scanning and paper feeding, recording on the recording paper 107 is completed. A recording operation for ejecting ink from the recording head 201 is performed based on control from a recording control unit (not shown).

  Further, in order to increase the recording speed, the recording is not performed only when the carriage 106 is scanned in the forward direction, but the recording is performed even when the carriage 106 moves in the backward direction to return to the home position h, that is, bidirectional recording. May be possible.

  Further, the ink cartridge 202 may constitute an ink jet cartridge in which an ink tank that stores recording ink and a recording head 201 that discharges ink toward the recording paper 107 are integrated. Further, the ink tank and the recording head 201 may be detachably held by the carriage 106. Furthermore, a recording head 201 configured to be capable of discharging a plurality of colors of ink from one recording head may be used.

  Further, at the position where the recovery operation described above is performed, a capping unit (not shown) that caps the front surface (formation surface of the ink discharge port) of the recording head 201, and a thickening in the recording head 201 in the capped state by the capping unit A recovery unit (not shown) that performs a head recovery operation such as removing ink and bubbles is provided. A cleaning blade (not shown) or the like is supported on the side of the capping unit so as to protrude toward the recording head 201, and the cleaning blade and the front surface of the recording head can be slidably contacted. . After the recovery operation, the cleaning blade protrudes into the moving path of the recording head, and the recording head is moved, so that unnecessary ink droplets and dirt adhered to the front surface of the recording head as the recording head moves. Wipe away.

(Configuration example of recording head)
FIG. 26 is a perspective view of a main part for explaining a configuration example of the recording head 201.
In the recording head 201 of this example, a plurality of discharge ports 300 are formed at a predetermined pitch, and the common liquid chamber 301 and each discharge port 300 are connected by each liquid path 302. A recording element 303 for generating ink discharge energy is disposed along the wall surface of each liquid path 302. The recording element of this example is a heater (electrothermal converter) for generating thermal energy. The recording element 303 and its drive circuit are made on silicon using semiconductor manufacturing technology. A temperature sensor (not shown) and a sub-heater (not shown) are also collectively formed on the same silicon by the same process as the semiconductor manufacturing process. The silicon plate 308 on which these electrical wirings are made is bonded to a heat radiating aluminum base plate 307. Further, the circuit connecting portion 311 on the silicon plate 308 and the printed board 309 are connected by an extra fine wire 310, and a signal from the recording apparatus main body is input through the signal circuit 312.

  The liquid path 302 and the common liquid chamber 301 are formed by an injection-molded plastic cover 306. The common liquid chamber 301 is connected to the above-described ink tank (see FIG. 25) via the joint pipe 304 and the ink filter 305, and ink is supplied from the ink tank to the common liquid chamber 301. The ink supplied from the ink tank to the common liquid chamber 301 and temporarily stored enters the liquid path 302 by capillary action, forms a meniscus at the discharge port 300, and fills the liquid path 302. Then, a heater as the recording element 303 is energized through an electrode (not shown), and when the heater generates heat, the ink on the recording element 303 is rapidly heated and bubbles are generated in the liquid path 302. . Due to the expansion of the bubbles, the ink droplet 313 is ejected from the ejection port 300.

(Ink characteristics)
The black (K) ink applied in this embodiment has a predetermined permeability, and the cyan (C), magenta (M), and yellow (Y) color inks have a permeability higher than the predetermined permeability. ing. According to this ink characteristic, the low penetrability black ink applied to the same region as the high penetrability color ink has an improved penetration speed, and the black ink penetrates quickly into the recording medium. Smear is suppressed.

  However, when the penetrability of the black ink is improved, not only the solvent component of the black ink but also the color material component penetrates into the inside of the recording medium at a high speed and in a large amount, and the density of the black image tends to be lowered. Therefore, in this embodiment, in order to reduce the decrease in the density of the black image, a component that aggregates the color material of the black ink is included in the cyan (C) ink. According to this ink configuration, the color material of the black ink is instantaneously aggregated, and a large amount of the aggregate can be left on the surface of the recording medium, so that it is not necessary to reduce the density of the black image.

As described above, in the present embodiment, low penetrability black ink and high penetrability cyan, magenta, and yellow color ink are used, and the cyan ink further includes a component that aggregates the color material of the black ink. Therefore, the black image can be fixed at high speed without causing a decrease in the density of the black image, and as a result, smear can be effectively suppressed.
The level of permeability is acetylenol (acetylene is a trade name of Kawaken Fine Chemicals; ethylene oxide added to acetylene glycol, ethylene oxide-2,4,7,9-tetramethyl-5-decyne- Adjust by changing the content of surfactants such as 4,7-diol (expressed by ethylene oxide-2,4,7,9-tetramethyl-5-decyne-4,7-diol) Is possible. By increasing the surfactant content, the permeability can be increased. Accordingly, in this example, the content of the surfactant is higher in the color ink than in the black ink.

  A polyvalent metal salt is preferably used as a component for aggregating the color material of the black ink. The polyvalent metal salt is composed of a divalent or higher polyvalent metal ion and an anion that binds to the polyvalent metal ion. Specific examples of the polyvalent metal ions include divalent metal ions such as Ca 2+, Cu 2+, Ni 2+, Mg 2+, and Zn 2+, and trivalent metal ions such as Fe 3+ and Al 3+. Examples of the anion include Cl-, NO3-, SO42-, and the like.

(Configuration example of control system in recording apparatus)
FIG. 27 is a block diagram for explaining a configuration example of a control system in the recording apparatus.
Reference numeral 400 denotes an interface for inputting a recording signal, 401 denotes an MPU, and 402 denotes a program ROM for storing a control program executed by the MPU 401. The MPU 401 executes data processing as will be described later. Reference numeral 403 denotes a dynamic RAM (DRAM) that stores various data (recording signals, recording data supplied to the recording head 201, and the like). The number of recording dots, the number of replacements of the ink tank and the recording head 201, etc. Can also be memorized. Reference numeral 404 denotes a gate array that controls supply of print data to the print head 201, and also controls data transfer among the interface 400, MPU 401, and DRAM 403. Reference numeral 400 is connected to a host computer (host device) (not shown). Image data to be recorded by the recording device can be input from the host computer. Reference numeral 405 denotes a carrier motor (CR motor) for conveying the recording head 201, and reference numeral 406 denotes a conveyance motor (LF motor) as a conveyance drive source for the recording paper 107. Reference numerals 407 and 408 denote motor drivers for driving the transport motor 405 and the carrier motor 406, respectively. Reference numeral 409 denotes a head driver for driving the recording head 201.

(Configuration example of data processing system)
FIG. 1 is a block diagram for explaining color adjacency matrix detection processing E1013, black uniform halftone matrix detection processing E1001, color dot application data generation processing E1, and recording color data generation processing E2 described later. It is.

  In FIG. 1, original Bk data D1000 is binary data obtained by performing binarization processing on multi-value data input from a host computer or binary data input directly from a host computer. The data is “1” and “0” corresponding to whether or not black (Bk) ink is ejected from the corresponding recording head 201, that is, whether or not black ink dots are formed. In the case of this example, the original Bk data D1000 becomes Bk data D1004 used for actual recording as it is. Hereinafter, these Bk data D1000 and D1004 are also referred to as black dot data. Further, the original C, M, and Y data D1001, D1002, and D1003 are multi-value data of a 2-bit index format as will be described later, and are developed in accordance with the resolution of the recording head 201 during recording. Hereinafter, these C, M, and Y data D1001 to D1003, D1005 to D1007 are also referred to as color dot data.

(Color adjacency matrix detection processing E1013)
FIG. 2 is a flowchart for explaining color adjacent matrix detection processing E1013 (see FIG. 1) for preventing boundary bleeding. Here, information (information such as the number of dots and duty) regarding the amount of color dots formed in the unit recording area is acquired based on the color data, and the color adjacent area which is the first recording area is detected based on the information.

  First, the number of color dots to be formed in the 64 × 32 matrix of interest is counted (step S401). That is, as shown in FIG. 1, based on the original C data D1001, the original M data D1002, and the original Y data D1003, the number of dots of C, M, Y ink formed in the target matrix is added up. Then, it is determined whether or not the total number of color dots in the target matrix is 410 dots or more (step S402). When the number of color dots in the target matrix is 410 or more, the color corresponding to the target matrix and the adjacent 64 × 32 matrix (adjacent matrices 1, 2, 3, 4 in FIG. 3A). The bit of the adjacency matrix information D1018 (see FIG. 1) is set to “1” (step S403). If the number of color dots in the target matrix is less than 410, the bit of the color adjacent matrix information D1018 corresponding to the target matrix is set to “0” (step S404). Subsequently, the position of the matrix of interest is shifted (step S405). Then, it is determined whether or not the color adjacent matrix detection processing E1013 for all the matrices has been completed (step S406). If the processing is completed, the processing is completed (step S407). If the processing is not completed, the process returns to step S402. The color adjacency matrix detection process E1013 is repeated.

  The threshold value for the number of color dots is not limited to 410, and can be set to an optimum value according to the characteristics of the ink and the characteristics of the printing apparatus. Also, the original C data D1001, M data D1002, and Y data D1003 do not necessarily have to be binarized data, and as a result may be data associated with whether or not to form ink dots. That's fine. In addition, when the number of C, M, and Y ink dots formed in the matrix of interest is added, weighting may be performed according to ink characteristics for each ink type.

  3A, 3B, and 3C are specific explanatory diagrams of the color adjacency matrix detection processing E1013.

  FIG. 3A shows a 64 × 32 matrix of interest and four adjacent matrices adjacent thereto. In this embodiment, the upper, lower, left, and right matrices adjacent to the matrix of interest are used as the adjacent matrix. This is to prevent boundary bleeding from occurring when black dots and color dots are adjacent to each other in the boundary region between the matrix of interest and the adjacent matrix. For the four matrices located at the diagonal of the matrix of interest, that is, the matrix located at the upper right, lower right, upper left, and lower left of the matrix of interest, the boundary area with the matrix of interest exists only as a point. It is not treated as an adjacency matrix. The size of the matrix and which of the eight matrixes adjacent to the target matrix is treated as the target matrix is appropriately set according to the characteristics of the ink system and the printing apparatus.

  FIG. 3B is an explanatory diagram of the total number of dots of color ink (cyan, magenta, and yellow ink) in each matrix. Matrix portions whose total number is 410 or more are hatched. FIG. 3C is an explanatory diagram of the color adjacency matrix information D1018 obtained as a result of performing the color adjacency matrix detection processing E1013. As described above, while shifting the position of the target matrix in the horizontal direction and the vertical direction, “1” is assigned to the target matrix having the count value of the number of color dots of 410 or more and the bit corresponding to the adjacent matrix adjacent to the target matrix. And “0” is set to the bits corresponding to the target matrix of less than 410. Therefore, the color adjacency matrix information D1018 is bitmap information as shown in FIG.

(Black uniform halftone matrix detection process E1001)
FIG. 4 is a flowchart for explaining the black uniform halftone trick detection process E1001. This detection process E1001 is a process for detecting an area (uniform halftone area) in which the degree of change in the recording duty of black dots is relatively small, such as shading (uniform halftone) recorded by black ink. Specifically, based on the black data, information on the relative difference in black dot formation amounts between adjacent unit recording areas (information on the number of dots and the difference in duty) is acquired, and the second recording area is based on the information. Detect a uniform halftone area. As will be described later, by applying color dots to the uniform halftone area detected by the detection processing E1001, the occurrence of color unevenness in the uniform halftone area can be reduced.

  FIGS. 5A and 5B are diagrams showing the target matrix A and four proximity matrices B, C, D, and E positioned on the upper, lower, left, and right sides of the target matrix A. FIG.

  First, the absolute value of the difference between the count value DA of black dots to be formed in the target matrix A and the count values DB, DC, DD and DE of black dots to be formed in the proximity matrices B, C, D and E That is, | DA-DB |, | DA-DC |, | DA-DD |, | DA-DE | are calculated (step S201). Next, the smallest value among the absolute values of these differences is acquired as the minimum difference dot number (step S202).

  For example, when DA = 100 dots, DB = 0 dots, DC = 50 dots, DD = 70 dots, DE = 100 dots, the minimum difference dot number is expressed by the following equation.

Minimum difference dot number = MIN {ABS (DA-DB), ABS (DA-DC), ABS (DA-DD), ABS (DA-DE)}
= MIN {ABS (100-0), ABS (100-50), ABS (100-70), ABS (100-100)}
= MIN {100, 50, 30, 0}
= 0
Here, ABS is defined as an absolute value, and MIN is defined as a function for calculating a minimum value.

  Next, the minimum difference dot number is compared with the threshold A, and it is determined whether or not it is smaller than the threshold A (step S203). For example, if the threshold A = 1, and the minimum difference dot number is 0 as described above, the bit of the black uniform halftone information corresponding to the matrix of interest A is set to “1” (step S204). On the other hand, when the minimum difference dot number is greater than or equal to the threshold A, the bit of the black uniform halftone information corresponding to the target matrix A is set to “0” (step S205). Subsequently, the position of the target matrix in the original Bk data D1000 is shifted (step S206). If the detection process E1001 for all the target matrices has not been completed, the process returns to the previous step S201, and if it has been completed, the detection process E1001 is terminated (S207).

  6A, 6B, and 6C are specific explanatory diagrams of the black uniform halftone matrix detection process E1001.

  FIG. 6A shows a target matrix composed of 64 pixels × 32 pixels. FIG. 6B shows the count number of black dots in each matrix (64 × 32 pixels) of the Bk data D1000. The black uniform halftone matrix detection process E1001 is executed while shifting the matrix of interest to the left in the figure. When the processing for the matrix for one line is completed, the processing is performed for the matrix for the next line. As a result of finishing the processing for all the matrices, black uniform halftone matrix information (D1009) as shown in FIG. 6C can be obtained. In FIG. 6C, the threshold A is set to 1.

(Color dot giving data generation process E1)
7A to 7D are explanatory diagrams of the color dot provision data generation process E1.
In this generation processing E1, first, as shown in FIG. 1, the arithmetic processing unit E1003 takes the logical sum of the color adjacency matrix information D1018 and the black uniform halftone matrix information D1009 to obtain the first color addition matrix information D1010. Is generated. Then, the arithmetic processing unit E1020 generates the second color addition matrix information D1020 by taking the logical product of the color addition matrix information D1010 and the original Bk data D1000. The second color provision matrix information D1020 corresponds to the Bk data D1000 in the 64 × 32 matrix in which the first color provision matrix information D1010 is set to “1”.

  In the generation process E1, cyan ink dot application data (C application data) D1011, magenta ink dot application data (M application data) D1012, and yellow based on the second color application matrix information D1020. Ink dot application data (Y application data) D1013 is generated. The C application data (D1011), the M application data (D1012), and the Y application data (D1013) are collectively referred to as color dot application data.

  The C giving data (D1011) includes the second color giving matrix information D1020 (the Bk data D1000 in the matrix in which the first color giving matrix information D1010 is set to “1”), as shown in FIG. 7B. It is generated by taking a logical product with a cyan mask (C mask) having a size of 10 (pixels) × 10 (pixels) (AND processing E1007 with the C mask in FIG. 7A). Similarly, the M provision data (D1012) includes the second color provision matrix information D1020 and a magenta mask (M mask) having a size of 10 (pixels) × 10 (pixels) as illustrated in FIG. It is generated by taking a logical product (AND processing E1008 with the M mask in FIG. 7A). Similarly, the Y addition data (D1013) includes the second color addition matrix information D1020 and a yellow mask (Y mask) having a size of 10 (pixels) × 10 (pixels) as shown in FIG. It is generated by taking a logical product (AND processing E1009 with the Y mask in FIG. 7A). Since the C, M, and Y masks have a size of 10 × 10, they are used repeatedly in the vertical and horizontal directions within the 64 × 32 size matrix so that the second color imparting matrix D1020 can be used. Logical AND.

  In this example, as shown in FIGS. 7B, 7C, and 7D, the C, M, and Y mask duties are 18%, 6%, and 5%, respectively. These duty factors are cyan ink dots, magenta ink dots, and yellow inks for improving image quality with respect to the matrix (64 × 32) in which the first color addition matrix information D1010 is set to “1”. This corresponds to the application amount when applying dots. The application amount of each color ink dot and the size of the mask are set according to the characteristics of the ink and the configuration of the printing apparatus. Further, the dots in the mask may be arranged with regularity, or may be arranged pseudo-randomly.

(Recording C, M, Y data (color data) generation process E2)
In the generation process E2, as shown in FIG. 1, the C, M, and Y original data D1001, D1002, and D1003 and the C, M, and Y addition data D1011 and D1012 are obtained in each of the arithmetic processing units E1010, E1011, and E1012. , D1013, and C, M, Y data D1005, D1006, D1007 for recording are generated.

  The color data (C, M, Y data) D1001, D1002, D1003, D1005, D1006, and D1007 in this example are multi-valued data in a 2-bit index format. Be expanded. As shown in FIG. 8A, corresponding development patterns are set in the 2-bit index data (00, 01, 10, 11).

  FIG. 8B shows logical processing in the arithmetic processing units E1010, E1011 and E1012, that is, 2-bit original color data D1001, D1002, D1003 and 1-bit color addition data (C, M, Y addition data) D1011. It is explanatory drawing of a calculation process with D1012 and D1013. When the 1-bit color imparting data is “1”, the calculated recording color data is converted to “01” only when the original color data is “00”. In the case of other original color data, the original color data is used as recording color data as it is.

(Recording operation based on recording C, M, Y, Bk data)
Based on the recording C, M, Y, and Bk data D1004 to D1007, the corresponding recording head 201 ejects C, M, Y, and Bk inks to record a color image on the recording paper 107. At that time, the recording color data D1005, D1006, and D1007 are developed in accordance with the resolution of the recording head 201.

  FIG. 9 shows a case where the present embodiment is applied to recording an image including a character portion and a shaded portion recorded with Bk ink and a solid portion recorded with color ink on a recording sheet. It is the figure which represented typically the processing result of.

  The character portion recorded with Bk ink is a region where black dots are formed based on the character data 2001. The shaded portion recorded with Bk ink is a uniform halftone region where black dots are formed based on the shaded data 2002. The solid portion recorded by the color ink is an area where color dots are formed with high duty based on the solid data (color solid data) 2003 of the color ink. Using the detection matrix 2000 as a target matrix, the color adjacent matrix detection process E1013 and the black uniform halftone trix detection process E1001 were performed while shifting the target matrix as the matrices M1 to M5.

  As a result, the character portion is not detected as a black high duty region by the detection processing E1000, and is not detected as a color adjacent region by the detection processing E1013. For this reason, the character portion is a region to which no color dot is applied, that is, a non-overlapping region 2004 of color dots. On the other hand, the region including the shaded portion is detected as a uniform halftone region by the detection processing E1001, and the region including the solid portion is detected as a color adjacent region by the detection processing E1013. For this reason, the areas of the matrixes M3 to M5 including the shaded portion and the solid portion are areas to which color dots are applied, that is, color dot overlapping areas 2005. Therefore, the non-overlapping region 2004 and the overstriking region 2005 of color dots are not mixed in the shaded portion, and it is possible to prevent image density unevenness that occurs when they are mixed.

  In general, the number of dots formed in a matrix unit varies in a character portion, and when a predetermined pattern is repeatedly recorded as in a shaded portion, the number of dots formed in a matrix unit is substantially constant. Therefore, as described above, character data and shaded data are discriminated by detecting an area where the difference in the number of formed dots from an adjacent matrix is small, and color dot addition data is generated only for the shaded data. It becomes possible.

  In this way, the occurrence of bleeding (boundary bleeding) in the boundary region between the black ink and the color ink application portion can be prevented by overprinting the color dots on the black ink application region adjacent to the color ink application region. Can do. In that case, blurring can be prevented by generating color dot application data so that color dots are overprinted on a black uniform halftone region such as a shaded portion. Further, the quality can be maintained by not generating the color dot giving data so that the color dots are not overprinted on the character portion. In particular, with respect to a black uniform halftone region such as a shaded portion, it is possible to prevent density unevenness and color unevenness due to a mixture of color dot overprinting regions and non-overprinting regions.

[Modification]
In the above-described black uniform halftone trick detection process E1001, a matrix having the same size as the matrix used in the color adjacent matrix detection process E1013 is used, but the matrix sizes may be different from each other.

[Second Embodiment]
In the present embodiment, the determination accuracy of the character portion and the shaded portion of the image is further improved, and deterioration of character quality and occurrence of color unevenness due to overstrike of color dots are prevented.

  FIG. 10 is a block diagram for explaining a configuration example of the data processing system of the present embodiment. In this example, an isolated region removal process E1002 and a bold process E1004 are added to the data processing system (see FIG. 1) in the first embodiment described above. Other processes are the same as those in the first embodiment. FIG. 11 is a flowchart for explaining the isolated region removal processing E1002, and FIG. 12 is a matrix configuration diagram for explaining the isolated region removal processing E1002.

  First, regarding the target matrix A and the eight proximity matrices B, C, D, E, F, G, H, and I, the number of matrices whose black uniform halftone matrix information (bit information) D1009 is “1” is acquired. (Step S301). In those nine matrices, it is determined whether or not the number of matrices whose matrix information D1009 is “1” exceeds a predetermined threshold B (step S302). Here, the threshold value B = 6. When the number of matrices in which the matrix information D1009 is “1” exceeds the threshold B, the matrix information D1009 corresponding to the target matrix A is set to “1” (step S303), and it does not exceed the threshold B In step S304, the matrix information D1009 corresponding to the target matrix A is set to “0”. Next, the focused matrix A is shifted (step S305), and it is determined whether or not the processing of all the matrices has been completed (step S306). If all the matrices have not been processed, the process returns to the previous step S301.

  As described above, the isolated region removal processing E1002 changes the black uniform halftone matrix information D1009 of the matrix A of interest from the relationship with the eight proximity matrices B, C, D, E, F, G, H, and I. The changed matrix information becomes the processing target information of the bold processing E1004 as the isolated region removal matrix information D1014.

  FIG. 13 is an explanatory diagram of the bold processing E1004. When the color provision matrix information D1010 of the target matrix is “1”, the color provision matrix upper D1010 of the four adjacent matrices on the top, bottom, left, and right is also set to “1”. The matrix information after such bold processing is input to the arithmetic processing unit E1003 as post-bold color provision matrix information D1030. The arithmetic processing unit E1003 calculates the logical sum of the matrix information D1030 and the color adjacency matrix information D1018 to generate first color provision matrix information D1010.

  FIG. 14 is a specific explanatory diagram of processing contents of the isolated region removal processing E1002 and the bold processing E1004 in the present embodiment.

  FIGS. 14A, 14B, and 14C are the same as FIGS. 6A, 6B, and 6C. That is, FIG. 14A represents a matrix of interest of 64 × 32 pixels. FIG. 14B shows the count number of black dots in each matrix (64 × 32 pixels) of the Bk data D1000. The black uniform halftone matrix detection process E1001 is executed while shifting the matrix of interest to the left in the figure. When the processing for the matrix for one line is completed, the processing is performed for the matrix for the next line. As a result of finishing the processing for all the matrices, black uniform halftone matrix information D1009 as shown in FIG. 14C can be obtained. In FIG. 14C, the threshold A is set to 1 as in FIG. 6C described above.

  FIG. 14D shows the result of performing the isolated region removal processing E1002 on the black uniform halftone matrix information D1009 of FIG. In the isolated region removal processing E1002, as described above, the number of matrices in which the matrix information D1009 is “1” in nine matrices including the target matrix and the eight proximity matrices exceeds the threshold B (= 6). If the matrix information D1014 of the matrix of interest is “1”, the matrix information D1014 of the matrix of interest is “0” when it does not exceed the threshold B (= 6). For example, in the matrix M11 and nine matrices including eight neighboring matrices, the number of matrices in which the matrix information D1009 is “1” is four below the threshold B (= 6). The matrix information D1014 is set to “0”. The same applies to the matrices M15, M41, and M45. Further, in the matrix M27 and the nine matrices including the eight neighboring matrices, the number of the matrices whose matrix information D1009 is “1” is two below the threshold value B (= 6). The matrix information D1014 is set to “0”. The same applies to the matrix M37. The matrix information of other matrices remains “0” or “1”.

  In the matrix in which the matrix information D1009 is “1”, the matrices M27 and M37 are isolated regions (isolated regions), and the matrices M11, M15, M41, and M45 are regions located at the corners of the halftone region. At this stage, both of these areas are excluded from the target area for color dot overlaying. The latter region is included in the target region for overprinting of color dots by the subsequent bold processing E1004. Thus, in the isolated region removal processing E1002, the matrix information D1014 of the isolated region is set to “0”. As a result, it is possible to discriminate the halftone area recorded by the black ink from the recording area such as a character deviating from the halftone area, and avoid overprinting of the color dots on the recording area such as the character.

  FIG. 14E shows post-bold color provision matrix information D1030 as a result of the bold process E1004. Here, it is assumed that the black high duty matrix information D1008 is all “0”, and the first color assignment generated as the logical sum of the matrix information D1008 and the isolated region removal matrix information D1014 of FIG. Bold processing was performed on the matrix information D1010. As described above, the bold processing is processing for setting the matrix information of the matrix located at the top, bottom, left, and right of the matrix whose matrix information is “1” to “1”. As a result, the matrixes M11, M15, M41, and M45 that have been removed from the target region for color dot overlay by the previous isolated region removal processing E1002 are included as target regions for color dot overlay. Dot assignment is guaranteed.

  As described above, in the present embodiment, by including the isolated region removal processing E1002 and the bold processing E1004, regions (for example, the solid portion and the shaded portion in FIG. 9) that need to be provided with color dots, the color It is possible to accurately determine and deal with a region that does not require dot application (for example, a character portion in FIG. 9).

[Third embodiment]
In the present embodiment, even when characters in a table, graph, etc. are shaded, deterioration of character quality and occurrence of color unevenness due to overstrike of color dots are prevented.

  FIG. 15 is an explanatory diagram of an example of recording an image including a character portion and shaded character portion recorded with Bk ink and a solid portion recorded with color ink. In the shaded character portion, the characters are shaded.

  In FIG. 15, the character part is an area where black dots are formed based on the character data 2001, the shaded character part is an area where black dots are formed based on the shaded character data 2002, and the solid part is color ink. This is an area where color dots are formed with a high duty based on solid solid data (color solid data) 2003. Using the detection matrix 2000 as a target matrix and shifting the target matrix as in the matrixes M1 to M5, an area where color dots are not applied (non-overprint area) 2004 and an area where color dots are applied (overprint area) 2005 are displayed. Set. In the matrices M3 and M4 corresponding to the shaded character portions, there are characters in the matrix M3, and there are no characters in the matrix M4. If the non-overlapping area 2004 is set so that no color dot is added to the character, as shown in FIG. 15, the area A1 where the color dot is not overprinted is overlaid on the shaded character part, and this is overprinted. The area A2 is mixed and color unevenness may occur. In the present embodiment, in order to prevent the occurrence of such color unevenness, even when there are characters in the shaded portion, the entire shaded portion is configured to be a color dot overlapping strike region.

  FIG. 16 is a block diagram for explaining a configuration example of the data processing system of this embodiment. In the case of this example, a vertical propagation process E1005 and a horizontal propagation process E1006 are added to the subsequent stage of the bold process E1004 of FIG. 10 in the second embodiment described above.

  FIG. 17 is an explanatory diagram of the propagation process E1005 in the vertical (downward) direction. Ma to Me are matrices arranged in the vertical direction (corresponding to the vertical direction of the image).

  FIG. 17A shows color addition matrix information (bitmap information) D1030 of the matrixes Ma to Me after the bold processing E1004. In this example, the upper matrix Ma is “1”, and lower than that. The matrixes Mb to Me on the side are “0”. FIG. 17B shows the count value C of the number of black dots in the matrixes Ma to Me. In this example, the count value C is 100 dots, 50 dots, 30 dots, 10 dots, 0 dots. It has become. In the propagation process E1005, by setting the matrix information D1030 of the matrix below the matrix information D1030 as “1” as a reference under the predetermined conditions, the matrix information D1030 is sequentially set to “1”. ) To generate color provision matrix information D1040 after the first propagation process. That is, the count value C of the matrix below the matrix Ma is sequentially examined, and the matrix information of the matrix before the count value C becomes “0” is set to “1”. In this example, since the count value C of the matrix Me is “0”, the matrix information of the matrices Mb to Md before that is set to “1”.

  FIG. 18 is an explanatory diagram of the propagation process E1006 in the horizontal (left / right) direction. Ma-1 to Ma-5 are matrices arranged in the horizontal direction (corresponding to the left-right direction of the image).

  FIG. 18A shows the matrix information D1040 after the propagation process E1005 as described above. In this example, the central matrix Ma-3 is “1”, and the other matrices are “0”. Yes. FIG. 18B shows the count value C of the number of black dots in the matrices Ma-1 to Ma-5. In this example, the count value C is 0 dot, 10 dots, 100 dots, 50 dots. , 0 dot. In the propagation process E1006, the matrix information D1040 of the left side and the right side of the matrix information D1040 is sequentially set to “1” under a predetermined condition with reference to the matrix having the matrix information D1040 of “1”. Color imparting matrix information D1050 after the second propagation processing as in c) is generated. That is, the count values C of the matrix on the left side and the right side of the matrix Ma-3 are sequentially checked, and the matrix information of the matrix before the count value C becomes “0” is set to “1”. In this example, since the count values C of the matrices Ma-1 and Ma-5 are “0”, the matrix information of the matrices Ma-2 to Ma-4 before that is set to “1”.

  FIG. 19 is an explanatory diagram when the image data of FIG. 15 is processed by the configuration of the present embodiment. As shown in the figure, by applying the processing of the present embodiment, the entire shaded area becomes a color dot overprinting area 2005. Therefore, density unevenness due to the mixture of the non-overlapping region and the overstrike region can be eliminated with respect to the shaded portion.

[Fourth Embodiment]
FIG. 20 is an explanatory diagram of an example of recording an image including a character portion, a shaded portion, and a solid portion recorded with Bk ink. The shaded part and the solid part are adjacent.

  In FIG. 20, the character portion is a region where black dots are formed based on the character data 1001, the shaded portion is a region where black dots are formed based on the shaded data 1002, and the solid portion is black ink solid. This is an area where black dots are formed with high duty based on data (Bk solid data) 1003. An area (non-overlapping area) 1004 to which color dots are not applied and an area (overlapping area) 1005 to which color dots are applied are shifted while the detection matrix 1000 is shifted as the matrices M1 to M5. Set. As shown in FIG. 20, if a shaded area includes a region A1 where color dots are not overprinted and a region A2 where the color dots are overprinted, color unevenness may occur. Therefore, in the present embodiment, the following configuration is adopted in order to prevent such color unevenness.

  FIG. 21 is a block diagram for explaining a configuration example of a data processing system in the present embodiment. In this example, a black high duty matrix detection process E1000 is added to the data processing system (see FIG. 16) of the third embodiment described above. The black high duty matrix is detected as a region to which color dots are applied in order to prevent smear. The black high duty matrix information D1008 detected by the detection processing E1000 is ORed with the isolated region removal matrix information D1014 after the isolated region removal processing E1002, and the information after the calculation is bold processing E1004. By performing the propagation process E1005 and the horizontal propagation process E1006, the color addition matrix information D1050 after the second propagation process is generated. The matrix information D1050 and the color adjacency matrix information D1018 are subjected to a logical OR operation E1003 to generate first color addition matrix information D1010.

(Black high duty matrix detection processing E1000)
FIG. 22 is a flowchart for explaining a black high duty matrix detection process E1000 for detecting a black high duty matrix as a region to which color dots are applied in order to prevent or reduce smear. Here, based on the black data, information on the amount of black dots formed in the unit recording area (information such as the number of dots and duty) is acquired, and the black high duty area is detected based on the information.

  First, paying attention to a matrix of 64 (pixels) × 32 (pixels), the number of black ink dots (hereinafter also referred to as “black dots”) to be formed in the focused matrix is counted (step S101). That is, based on the original Bk data D1000 (see FIG. 21), the number of black dots formed in the target matrix is counted.

  Subsequently, it is determined whether or not the black dot count value is 758 or more, that is, whether or not the recording duty is about 37% (= 758 / (64 × 32)) or more (step S102). When the number of black dots is 758 or more, the black high duty matrix information (bit information) D1008 (see FIG. 21) corresponding to the target matrix is set to “1” (step S103). When the count value of the number of black dots is less than 758, the black high duty matrix information D1008 corresponding to the target matrix is set to “0” (step S104). Subsequently, the position of the target matrix in the original Bk data D1000 (see FIG. 21) is shifted (step S105), and it is determined whether or not the processing for all the target matrices has been completed (step S106). If the detection process E1000 for all the target matrices in the original Bk data D1000 is not completed, the process returns to the previous step S102, and if it is completed, the detection process E1000 is terminated (step S107).

  The threshold value of the number of black dots is not limited to only 758, and can be set to an optimum value in accordance with the ink characteristics and the printing apparatus characteristics.

  23A, 23B, and 23C are specific explanatory diagrams of the black high duty matrix detection process E1000.

  FIG. 23 (a) shows a target matrix composed of 64 pixels × 32 pixels. In an image in which a solid portion to which ink is applied and a blank portion to which ink is not applied are clear like black characters, if the matrix size is too small, “1” and “0” of the black high duty matrix information D1008 The response of whether or not to add color dots in response to “is too good. For this reason, even a small character may be provided with color dots and the character sharpness may not be maintained. On the other hand, if the matrix size is too large, the responsiveness of whether or not to add color dots deteriorates, and the desired color dots cannot be applied, which may cause smear. Therefore, the matrix of interest is set to an appropriate size according to the characteristics of the ink system and the printing apparatus.

  FIG. 23B is an explanatory diagram of the count value of the number of black dots in each target matrix of the Bk data D1000 (see FIG. 21), and the matrix portion having the count value of 758 or more is hatched. . FIG. 23C is an explanatory diagram of the black high duty matrix information D1008 obtained as a result of the black high duty matrix detection processing E1000. As described above, while shifting the position of the target matrix in the horizontal direction and the vertical direction, the bit corresponding to the target matrix whose black dot count value is 758 or more is set to “1”, and the matrix corresponding to less than 758 is supported. Set “0” to the bit to be set. Therefore, the black high duty matrix information D1008 is bitmap information as shown in FIG.

  FIG. 24 is an explanatory diagram when the image data of FIG. 20 is processed by the configuration of the present embodiment. As shown in the figure, by applying the processing of the present embodiment, the entire shaded portion adjacent to the black image becomes a color dot overlapping region 2001. Therefore, density unevenness due to the mixture of the non-overlapping region and the overstrike region can be eliminated with respect to the shaded portion.

[Other Embodiments]
The present invention is not limited to the serial scan type recording apparatus as described above, but also for a full line type recording head using a recording head extending over the entire width direction of the recording area on the recording medium. Even can be applied.

  Further, in each of the above-described embodiments, a mode is described in which all color inks (cyan, magenta, and yellow) used for recording are applied as color inks that are applied over black ink in order to suppress boundary bleeding. However, the present invention is not limited to this. The ink applied over the black ink may be at least one of all the color inks used for recording.

  In the above-described embodiment, cyan, magenta, and yellow ink are used as the color ink types. However, the present invention is not limited to this, and light cyan having a lower color material density than cyan ink. At least one ink selected from the group of light magenta ink having a lower color material density than ink and magenta ink, and dark yellow, red ink, green ink and blue ink having a lightness lower than that of yellow ink is further used in combination. May be. In the form using light cyan ink and light magenta ink, it is preferable to apply light cyan ink and light magenta ink as ink to be applied over black ink, without applying cyan ink and magenta ink. . This is because the light cyan ink and the light magenta ink have a low density, so that the color of black is hardly changed even when superimposed on black.

  Furthermore, in each of the above-described embodiments, only the cyan ink among the color inks includes a component that aggregates the color material of the black ink, but the present invention is not limited to this. For example, in addition to cyan ink, the above components may be included in magenta ink and / or yellow ink, or the above components may be included only in magenta ink or yellow ink instead of cyan ink. In any case, it is preferable to apply the color ink containing the above components to a region where black is formed.

  In the above-described embodiment, the color ink containing a component that aggregates the color material of the black ink is used, but the present invention is not limited to this. From the viewpoint of smear suppression, it is not essential to aggregate the black ink coloring material. Therefore, it is not necessary to use a color ink containing the above components.

It is a block diagram for demonstrating the flow of the data processing in the 1st Embodiment of this invention. 3 is a flowchart for explaining color adjacency matrix processing in FIG. 1. (A) is an explanatory view of the relationship between the matrix of interest and the adjacent matrix in the color adjacent matrix detection process of FIG. 1, (b) is an explanatory view of the count value of the number of color dots in the matrix, and (c) is a color display. It is explanatory drawing of adjacency matrix information. 2 is a flowchart for explaining black uniform halftone matrix detection processing in FIG. 1. (A) is explanatory drawing of the attention matrix in the detection process of the black uniform halftone matrix of FIG. 1, (b) is explanatory drawing of the relationship between the attention matrix and proximity | contact matrix. (A) is an explanatory diagram of a matrix of interest in the detection process of the black uniform halftone matrix of FIG. 1, (b) is an explanatory diagram of the count value of the number of black dots in the matrix, and (c) is a black uniform halftone. It is explanatory drawing of matrix detection information. (A) is explanatory drawing of the production | generation process of the color dot provision data in FIG. 1, (b), (c) and (d) are explanatory drawings of C mask, M mask, and Y mask in (a). It is. (A) is explanatory drawing of the color original data in FIG. 1, and its expansion | deployment pattern, (b) is explanatory drawing of the arithmetic processing with respect to color original data. It is explanatory drawing of the example of recording by the 1st Embodiment of this invention. It is a block diagram for demonstrating the flow of the data processing in the 2nd Embodiment of this invention. It is a flowchart for demonstrating the isolated area | region removal process in FIG. (A) is explanatory drawing of the attention matrix in the detection process of the black uniform halftone matrix of FIG. 10, (b) is explanatory drawing of the relationship between the attention matrix and proximity | contact matrix. It is explanatory drawing of the relationship between the attention matrix and proximity | contact matrix in the isolated area | region removal process of FIG. (A) is an explanatory diagram of a matrix of interest in the data processing of FIG. 10, (b) is an explanatory diagram of a count value of the number of black dots in each matrix of Bk data, and (c) is a black uniform half in FIG. FIG. 10D is an explanatory diagram of tone matrix information, FIG. 10D is an explanatory diagram of isolated region removal matrix information in FIG. 10, and FIG. 10E is an explanatory diagram of color provision matrix information after holding in FIG. It is explanatory drawing of the example of a recording of the image containing a character, a shaded character, and a color solid. It is a block diagram for demonstrating the flow of the data processing in the 3rd Embodiment of this invention. (A), (b), (c) is explanatory drawing of the propagation process to the orthogonal | vertical direction in FIG. (A), (b), (c) is explanatory drawing of the propagation process to the horizontal direction in FIG. It is explanatory drawing of the example of recording by the 3rd Embodiment of this invention. It is explanatory drawing of the example of a recording of the image containing a character, a shaded character, and Bk solid. It is a block diagram for demonstrating the flow of the data processing in the 4th Embodiment of this invention. It is a flowchart for demonstrating the detection process of the black high duty matrix in FIG. (A) is an explanatory diagram of a matrix of interest in the black high duty matrix detection processing of FIG. 22, (b) is an explanatory diagram of a count value of the number of black dots in the matrix, and (c) is a black high duty matrix detection. It is explanatory drawing of information. It is explanatory drawing of the example of recording by the 4th Embodiment of this invention. 1 is a schematic perspective view of a recording apparatus according to a first embodiment of the present invention. FIG. 26 is a perspective view of a main part of the recording head in FIG. 25. FIG. 26 is a block configuration diagram of a control system in the recording apparatus of FIG. 25. It is explanatory drawing of the example of a recording by a prior art.

Explanation of symbols

106 Carriage 107 Recording paper (recording medium)
201 Recording Head 500 Recording Control Unit D1000 Original Bk Data D1001 Original C Data D1002 Original M Data D1003 Original Y Data D1004 Recording Bk Data D1005 Recording C Data D1006 Recording M Data D1007 Recording Y Data D1008 Black High Duty Matrix Information D1009 Black uniform halftone matrix information D1018 Color adjacent matrix information E1000 Black high duty matrix detection processing E1001 Black uniform halftone matrix detection processing E1013 Color adjacent matrix detection processing E1 Color dot application data generation processing

Claims (19)

Using a recording head capable of ejecting black ink and at least one color ink, the black ink on the recording medium based on black data for ejecting the black ink and color data for ejecting the color ink In an ink jet recording apparatus for recording an image by forming black dots by the color ink and color dots by the color ink,
First detection means for detecting, as a first recording area, a recording area in which the number of color dots formed in the unit recording area on the recording medium is equal to or greater than a first threshold and a recording area adjacent thereto based on the color data When,
Second detection means for detecting a second recording area in which the number of black dots formed between adjacent unit recording areas is less than a second threshold based on the black data;
Application for applying the color dots in the first recording area and the second recording area based on the black data corresponding to the first recording area and the black data corresponding to the second recording area Grant data generation means for generating data;
Recording color data generating means for generating the recording color data by reflecting the assigned data in the color data;
Control means for performing recording by controlling the recording head based on the black data and the recording color data;
An ink jet recording apparatus comprising:   The first detection means counts the number of black dots formed in a unit recording area of L pixels × M pixels (L and M are natural numbers of 1 or more) based on the color data, and the count number The inkjet recording apparatus according to claim 1, wherein the unit recording area equal to or greater than the first threshold and the unit recording area adjacent thereto are detected as the first recording area.   The second detection means counts the number of black dots formed in a unit recording area of L pixels × M pixels (L and M are natural numbers of 1 or more) based on the black data, and at least one 3. The inkjet recording apparatus according to claim 1, wherein a unit recording area in which a difference in the number of dots from an adjacent unit recording area is less than the second threshold is the second recording area. For each of the plurality of second recording areas detected for each unit recording area by the second detection means, whether or not the number of the second recording areas existing in the peripheral area is smaller than a third threshold value. An area removing unit that judges and removes the second recording area determined to be less than the third threshold from the plurality of second recording areas;
Area expanding means for expanding the third recording area obtained by removing the area by the area removing means to the fourth recording area;
With
The application data generation unit generates application data for applying the color dots in the fourth area based on the black data corresponding to the fourth recording area. 4. The ink jet recording apparatus according to any one of 3 above. The second detection means detects whether or not the second recording area for each predetermined unit recording area,
The area removing means is configured such that the number of the second recording areas within the range of A × B (A and B are natural numbers of 1 or more) of the unit recording area including the focused second recording area is the third threshold value. 5. The inkjet recording apparatus according to claim 4, wherein the second recording area of interest is removed from the second recording area detected by the second detection unit when the value is less than the second recording area. The second detection means detects whether or not the second recording area for each predetermined unit recording area,
6. The area expanding means expands the third recording area by at least one unit recording area in at least one of up, down, left and right directions to form the fourth recording area. 2. An ink jet recording apparatus according to 1. Propagation processing means for expanding the fourth recording area in at least one of the vertical direction and the horizontal direction to form a fifth recording area according to the number of black dots formed in the recording area outside the fourth recording area. The inkjet recording apparatus according to claim 6, comprising: Third detection means for detecting a sixth recording area in which the black dots are formed with a relatively high duty based on the black data;
The grant data generation means generates the grant data based on the black data corresponding to each of the first recording area, the second recording area, and the sixth recording area. Item 8. The ink jet recording apparatus according to any one of Items 1 to 7.   The third detection unit counts the number of black dots formed in a unit recording area of L pixels × M pixels (L and M are natural numbers of 1 or more) based on the color data, and the count number The inkjet recording apparatus according to claim 8, wherein the unit recording area having a threshold value equal to or greater than a fourth threshold is detected as the sixth recording area.   The application data generation means generates the application data by taking a logical product of the black data corresponding to the first recording area and the second recording area and a mask for applying color dots. An ink jet recording apparatus according to claim 1.   The inkjet recording apparatus according to claim 10, wherein the color ink is a plurality of inks of different colors, and the mask is provided corresponding to each ink color of the plurality of color inks.   12. The ink jet recording according to claim 1, wherein the recording color data generating unit generates the recording color data by calculating a logical sum of the color data and the added data. apparatus.   The inkjet recording apparatus according to claim 1, wherein the color ink includes yellow, magenta, and cyan inks.   The first detection unit is configured to output the yellow ink, the magenta based on yellow data for ejecting the yellow ink, magenta data for ejecting the magenta ink, and cyan data for ejecting the cyan ink. 14. The ink jet recording apparatus according to claim 1, wherein a recording area in which dots are formed by ink and the cyan ink and a recording area adjacent thereto are detected as a first recording area.   The inkjet recording apparatus according to claim 1, wherein the black ink is an ink having a relatively low permeability, and the color ink is an ink having a relatively high permeability.   16. The ink jet recording apparatus according to claim 1, wherein at least one of the color inks includes a component that aggregates the color material of the black ink.   The ink jet recording apparatus according to claim 16, wherein the color ink containing the component is a cyan ink. Using a recording head capable of ejecting black ink and at least one color ink, the black ink on the recording medium based on black data for ejecting the black ink and color data for ejecting the color ink In an ink jet recording apparatus for recording an image by forming black dots by the color ink and color dots by the color ink,
First detection means for acquiring information on the formation amount of the color dots in the unit recording area based on the color data and detecting the first recording area based on the information on the formation amount;
Second detection means for acquiring information on a relative difference in the formation amount of black dots between adjacent unit recording regions based on the black data, and detecting a second recording region based on the information on the relative difference in the formation amount; ,
Application for applying the color dots in the first recording area and the second recording area based on the black data corresponding to the first recording area and the black data corresponding to the second recording area Grant data generation means for generating data;
Recording color data generating means for generating the recording color data by reflecting the assigned data in the color data;
Control means for performing recording by controlling the recording head based on the black data and the recording color data;
An ink jet recording apparatus comprising: Using a recording head capable of ejecting black ink and at least one color ink, the black ink on the recording medium based on black data for ejecting the black ink and color data for ejecting the color ink In an inkjet recording method for recording an image by forming black dots by the color ink and color dots by the color ink,
Based on the color data, a recording area in which the color dots are formed and a recording area adjacent thereto are detected as a first recording area,
Based on the black data, a second recording area in which the change rate of the recording duty of the black dots is relatively small,
Application for applying the color dots in the first recording area and the second recording area based on the black data corresponding to the first recording area and the black data corresponding to the second recording area Generate data,
A color data for recording is generated by reflecting the assigned data in the color data,
An ink jet recording method, wherein recording is performed by controlling the recording head based on the black data and the recording color data.