JP3155831B2 - Ink jet recording method and ink jet recording apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording method.

[0002]

2. Description of the Related Art With the spread of information processing devices such as copying machines, word processors, computers, and communication devices, a recording head of an ink jet system is used as one of image forming (recording) devices of those devices. Those that perform digital image recording are rapidly becoming widespread. In such a printing apparatus, in order to improve the printing speed, a printing head in which a plurality of printing elements are integrated and arranged is used in which a plurality of ink ejection ports and liquid paths are integrated. Further, in recent years, a type having a plurality of the recording heads corresponding to color has been widely used.

In such a color printer, a color image is formed by forming mixed color dots by landing ink droplets of different colors, but if the ink absorption performance of the recording medium is inappropriate in the vertical and horizontal directions, The post-strike ink penetrates into the lower part of the pre-strike ink, and the landing diameter becomes larger on the paper.
FIG. 18 shows a state in which the trailing-printed Y protrudes outside the first-printed C in the green image. FIG. 1 shows a schematic view of a dot array observed from a printing surface of a recording medium and a cross-sectional view of one dot therein. Next, when the state of the G solid portion is set to a level visible to the naked eye, after all, as shown in FIG. 19, G (hatched portion) due to the mixture of C and Y is inside, and Y protrudes outside the outside. (Y that is not pure Y but also contains C, that is, becomes a yellow-rich green. Indicated as G (Y)). Since this example is a serial printer, after the carriage prints each line, the carriage performs a line feed operation in accordance with the print width and continues printing the next line. If G solids having an area over a plurality of lines are printed, each line corresponds to the G solid portion in FIG. That is,
G (Y) protrudes from the peripheral portion of each line printing portion. C and Y of the next line are printed on G (Y).
As described above, C and Y landed after yellow-rich G (Y) penetrate into the lower part of the previously-printed ink, resulting in a more yellowish color than G in FIG. 19 (this color is G (Y) ′). And). In other words, as shown in FIG.
Horizontal stripes of (Y) 'occur. As a whole, the stripes are whitish because they stand out linearly horizontally. This phenomenon is called a color mixing streak, and significantly degrades the image quality of the solid color mixed portion.

A method for preventing such a connecting streak is described in U.S. Pat.
SP 4,855,752 or JP-A-63-31
No. 5249. FIG. 1 shows this method.
This will be described with reference to FIGS.

A print head 101 is provided separately for each of the colors Y, M, C, and K, and is arranged on a carriage 102. The carriage 102 is in the main scanning direction (the horizontal direction in FIG. 14).
To perform the printing operation. The recording paper 103 is conveyed in a sub-scanning direction (upward in the figure) perpendicular to the main scanning direction to perform a line feed operation. In this example, the number of nozzles of the print head 101 is eight for simplicity. The number of nozzles is not limited to eight. Print head 101
Is printed on the same line in the order of K, C, M, and Y to form a color image. Next will be described the arrangement of the vertical print head (paper feed direction) in FIG. 14. Each color print head 101 is arranged so as to be shifted by D1 in the recording paper conveyance direction (downstream in the paper feed direction) from the adjacent head on the preceding side. Therefore, the vertical position of the first nozzle of each print head differs for each color. In other words, the print head of the post-strike ink is arranged on the downstream side in the paper feeding direction.

FIG. 15 shows an image forming state when a printing operation is performed with such a print head arrangement. The horizontal direction is the main scanning direction, and the upward direction is the recording paper transport direction. Also, the ink arrangement for each color is shown using a fill pattern corresponding to each color print head. Printing is performed for each scan of the carriage, and FIG. 7 shows a print portion from the first scan to the third scan. In the case of this embodiment, the line feed width between each scan is the entire nozzle width of the print head 101. The print head rows Y, M, C, and K are slightly shifted in the horizontal direction for each scan to indicate the print area for each ink for each scan. Therefore, the print start position does not always deviate for each scan. In addition, the arrangement of each color ink on the recording paper is such that the post-strike ink is written on the pre-strike ink, but this is simplified for expression in the drawing. As described in FIG. 18, the actual arrangement of the ink on the recording paper is such that the post-strike ink penetrates into the lower layer of the pre-strike ink.

Here, attention is paid to the connection portion of each color ink on the recording paper. Since the print head 101 is arranged so as to be shifted to the downstream side in the recording paper conveyance direction as compared with the post-strike ink, the line feed portion connection does not match for each color. FIG. 21 shows a connection portion for each color in the conventional example. In the case of the conventional printing method, the connection portion of the line feed is located at the same position for all the ink colors as indicated by the thick line portion. Therefore, as described above, a streaked stitch occurs. However, in the case of the present example shown in FIG. 15, since the connecting portion is different for each ink color, a mixed color connecting streak does not occur. FIG. 17 shows an example in which G is formed by mixing C and Y. First, the first ink C is ejected, and then the second ink Y is ejected. The Y of the post-strike ink penetrates into the lower layer of C, resulting in G. However, since C is shifted to the upstream side in the recording paper conveyance direction, the connecting portion of C becomes a single color of only C (Y There is no digging phenomenon due to). Then, the C and Y discharges are performed in the printing of the second scan. That is, G shown in FIG.
A portion different in hue from the overall dominant color G such as (Y) 'does not occur, and as a result, a stitch of a color mixture does not occur. Similarly, in the case of other mixed colors, since the connecting portion differs for each color, printing can be performed without a difference in hue from the overall dominant color at the connecting portion.

FIG. 16 shows a case where this printing method is viewed in pixel units. In this figure, two lines (two times the width of the entire nozzle of the print head) are printed, and in this case, the post-strike ink of each color is one pixel (one square) downstream in the recording paper transport direction. It is arranged with a gap. The numbers in the squares correspond to the nozzle numbers of the print heads, and indicate 1 to 8 from the top. The ink ejection order is K, C, M, and Y, and indicates the first to third scans. Also in the case of this example, the line feed width and the total nozzle width of each print head are the same. First, at the time of the first scan, the first-shot K head uses all nozzles (first
To 8). Since the next C is shifted by one pixel in the recording paper conveyance direction, printing for seven pixels from the second to eighth nozzles is performed during the first scan. Similarly, the next M is the third to
The printing is performed for six pixels of the eighth nozzle, and Y is printed for five pixels of the fourth to eighth nozzles. As described above, at the time of the first scanning, the upper portion of the print head is not printed by an amount corresponding to the shift of the post-printing head in the recording paper conveyance direction. After the line feed operation, the second scan is performed. Second
In scanning, the print heads of all colors are all nozzle widths (1st to 8th).
Nozzle) prints. However, C which is the after-hit head,
M and Y perform printing of the preceding line portion at the time of main scanning. In the third scan of the next final scan, printing by the K head is not performed, and printing is performed only on C, M, and Y where the print portion remains, and printing for two lines is completed. In this manner, at the time of the first and last scans, the post-printing head does not use all the nozzles, but shifts the data corresponding to the pixels for which the connecting portion has been shifted.

[0009]

The above is a conventional measure for preventing a streaky streaky streak, but this method cannot prevent image deterioration due to uneven printing of a print head. In the case where a gap is generated at the joint portion due to the variation in the accuracy of paper feed, as shown in FIG. 17, the space between C and C is opened, and the Y ink to be ejected later protrudes there, thereby preventing the occurrence of the streaks of mixed color. However, there is a disadvantage that the image quality is remarkably deteriorated.

[0010] The present invention has been made in view of the above points,
An object of the present invention is to provide an ink jet recording method capable of preventing occurrence of streaks of mixed colors and recording a high quality color image.

[0011]

In order to achieve the above object, according to the present invention, a recording means in which a plurality of recording element arrays for ejecting inks of different colors are arranged relatively to a recording material. An inkjet recording method for recording a color image on the recording material by ejecting a plurality of different color inks from the recording unit while performing main scanning in a direction different from the recording element row direction, The recording is performed by dividing the recording element row of each color into a plurality of blocks in the recording element row direction, and recording the thinned images in a complementary relationship to each other by using the divided different blocks in each of a plurality of main scans. A printing step of completing printing of a printing area extending in the main scanning direction on the material, and the printing unit and the printing unit corresponding to the length of the one divided block for each main scan. A sub-scanning step of performing sub-scanning in the printing element row direction, and a boundary extending in the main scanning direction of the printing area formed by main scanning of printing elements at both ends of each block of the printing element row of each color. The position of the section is different for each color in the sub-scanning direction. Further, the present invention, while performing a main scanning relative to a recording material in a direction different from the recording element row direction, a printing unit in which a plurality of printing element rows that eject inks of different colors are arranged, An ink jet recording apparatus that records a color image on the recording material by discharging a plurality of different color inks from a recording unit, wherein a recording element row of each color of the recording unit is divided into a plurality of blocks in the recording element row direction. Dividing and recording a thinned image having a complementary relationship with each other by using the divided different blocks in each of a plurality of main scans, thereby completing recording of a recording area extending in the main scanning direction on the recording material. Control means, and sub-scan means for sub-scanning the recording means and the recording material in the recording element row direction by an amount corresponding to the length of the divided one block for each main scan. The position of the boundary extending in the main scanning direction of the recording region formed by main scanning of the recording elements at both ends of each block of the recording element row of each color is different for each color in the sub-scanning direction. It is characterized by the following.

As described above, the recording area is shifted for each color (the position of the boundary extending in the main scanning direction of the recording area is changed), and the recording area is recorded by a plurality of main scans. The occurrence of connecting streaks is suppressed.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 8 is a perspective view of a color ink jet recording apparatus to which the present invention is applied. The print head 1 is a device that has a plurality of nozzle arrays, performs a state change in ink using thermal energy, and discharges ink droplets from discharge ports to perform image recording by forming dots on a recording medium. Different color inks are ejected from different print heads, and a color image is formed on a recording medium by mixing colors of these ink droplets. The print head rows 1K (black), 1C (cyan), 1M (magenta), and 1Y (yellow) are mounted on the carriage 201 so as to be shifted from each other in the sub-scanning direction as described later. Is discharged. For example, when making red (hereinafter R), first, magenta (hereinafter M) is landed on the recording medium, and then yellow (hereinafter Y) is landed on the dot of M so that it can be seen as a red dot. Similarly, in the case of green (hereinafter G), in the order of C and Y, in the case of blue (hereinafter B),
The color is formed by landing in the order of C and M, respectively. However, as in the case of FIG. 20, since the print heads are arranged at a constant interval (P1) in the main scanning direction, for example, when performing solid printing of G, after printing C, printing of Y is delayed by 2 * P1 minutes. Is performed. That is, the Y solid is printed on the C solid. The carriage 201 moves on a sliding shaft by transmitting power from a carriage drive motor 8 by belts 6 and 7. Printing in the digit direction is performed during the operation in the main scanning direction. The recovery unit 400 has a function of always maintaining the state of the print head in a good state, and in a non-print state, the cap row 420 closes the ejection surface of the print head to prevent drying or the like. For this reason, the position where the carriage 201 faces the recovery unit 400 is called a home position (hereinafter, HP). In the present example, the normal printing operation is performed from left to right in FIG. 8 since the carriage moves from this HP to perform printing. In the sub-scanning direction, the recording medium is fed by a paper feed motor (not shown). The direction C in the drawing is the paper feeding direction. The ink is supplied from the ink cassettes 10K and 10K.
C, 10M, and 10Y are supplied for each color from the supply tube row 9 to the print head on the carriage.

Unlike a monochrome printer that prints only characters, printing a color image image requires various elements such as color development, gradation, and uniformity. Regarding uniformity in particular, slight variations in the nozzle unit that occur during the print head manufacturing process affect the ejection amount and ejection direction of each nozzle when printing, and eventually result in uneven density of the printed image. This may cause deterioration of image quality.

Therefore, in this embodiment, each color print head row is divided into a plurality of blocks, and the thinned-out images having a complementary relationship with each other are recorded in order by a plurality of main scans using different blocks. After the scanning is completed, the image is recorded so that the sub-scanning of the block width is performed. Hereinafter, this fine recording method will be described.

A specific example of the density unevenness will be described with reference to FIGS. 10 and 11 using a single-color print head as an example for simplification. FIG.
In FIG. 9A, reference numeral 91 denotes a print head, which is composed of eight multi-nozzles for simplicity. 93
Is an ink droplet ejected by the multi-nozzle 92, and usually has a uniform ejection amount as shown in FIG.
Ideally, ink is ejected in a uniform direction. If such ejection is performed, dots of uniform size are landed on the paper surface as shown in FIG. 10B, and a uniform image without density unevenness is obtained as a whole. (FIG. 10
(C)) However, actually, as described above, the nozzle 1
Each one has a variation, and if printing is performed in the same manner as described above, the size and direction of the ink drops ejected from the respective nozzles vary as shown in FIG. And landed on the paper as shown in FIG. 11 (b). According to this figure,
Area factor 1 periodically in the head main scanning direction
A blank portion of less than 00% occurs, conversely dots overlap more than necessary, or a white streak as shown in the center of the figure occurs. The collection of dots landed in such a state has a density distribution shown in FIG. 11C with respect to the nozzle arrangement direction, and as a result, these phenomena usually show the density unevenness as seen by human eyes. Is sensed as In addition, streaks due to variations in the paper feed amount may be noticeable.

Therefore, as a countermeasure against the density unevenness and the connecting streaks, the following method is proposed in Japanese Patent Application Laid-Open No. 60-107975 in a monochrome ink jet recording apparatus. The method will be briefly described with reference to FIGS. According to this method, the print head 91 is scanned three times in order to complete the print area shown in FIGS. 10 and 11, but an area of half a pixel unit is completed in two passes. In this case, the eight nozzles of the print head are divided into groups of upper four nozzles and lower four nozzles, and the dots printed by one nozzle in one scan are defined image data according to a predetermined image data array. It has been thinned out by about half. Then, dots are embedded in the remaining image data at the time of the second scan, and printing of a 4-pixel unit area is completed. The above recording method is called a fine recording method. When this recording method is used, even if the print head shown in FIG. 11 is used, the influence on the print image specific to each nozzle is reduced.
As shown in FIG. 11B, the black streak and the white streak as shown in FIG. 11B become less noticeable. Therefore, the density unevenness also
As shown in FIG. 2 (c), it is considerably relaxed as compared with the case of FIG. When such recording is performed, in the first scan and the second scan, the image data is divided in such a manner that the image data is complemented with each other according to a certain arrangement. Usually, this image data arrangement (thinning pattern) is as shown in FIG. It is most common to use a staggered grid for each vertical and horizontal pixel. Therefore, the unit print area (here, in units of 4 pixels)
In this case, printing is completed by the first scan for printing a staggered grid and the second scan for printing an inverted staggered grid. FIGS. 13A, 13B, and 13C show how the recording of a certain area is completed when the staggered and inverted staggered patterns are used, as in FIGS.
This is described using a print head having nozzles. First, in the first scan, a staggered pattern is printed using the lower four nozzles (FIG. 13A). Next, in the second scan, the paper is fed for four pixels (1/2 of all the nozzles), and the inverted zigzag pattern is printed (FIG. 13B). Further, in the third scan, the paper is fed again by four pixels (1/2 of all the nozzles), and the staggered pattern is printed again (FIG. 13C). In this manner, by sequentially performing paper feed in units of four pixels and recording in a zigzag or inverted zigzag pattern, a recording region in units of four pixels is completed for each scan.

As described above, by completing printing in the same area with two different types of nozzles, it is possible to obtain a high-quality image without density unevenness.

In this embodiment, the print head arrays 1Y, 1Y
The arrangement of M, 1C, and 1K is shifted by an integral multiple of the recording density in the sub-scanning direction, so that the connecting portion of the recording area for each color is shifted.

Therefore, as for the management of the print data, not only the line to be printed but also the data of the previous print line is managed. FIG. 9 is a block diagram illustrating a control unit that performs data processing of the present example. In the figure, reference numeral 500 denotes a host computer that outputs print data, and a RECEIVE BUFF that receives print data sent from the host computer 500.
ER area, PRI for receiving data converted for recording
A RAM having an NT BUFFER area and a WORK area for temporarily storing operation results, etc., 502 is an MPU for controlling the processing of converting received print data into recording data and controlling the operation of various loads in the apparatus, 503 MPU50
A driver that operates various loads in response to signals from 2, 5
Reference numeral 04 denotes a print head (corresponding to 1 in FIG. 8), reference numeral 505 denotes a motor for performing suction recovery processing for removing thickened ink in nozzles of the print head via a cap when power is turned on or before recording is started, Reference numeral 506 denotes a motor for feeding paper,
Reference numeral 7 denotes a motor for reciprocating the carriage in the main scanning direction, reference numeral 508 denotes various sensors (not shown), reference numeral 509 denotes a lamp provided in an operation unit (not shown) for displaying a selected mode or the like, and reference numeral 510 denotes a lamp (not shown). A group of keys provided in the operation unit for setting various modes.

The print data from the host computer 500 is received by the receive buffer on the RAM 501. Next, according to the instruction from the MPU 502, the data is converted into a data array suitable for printing, and the print buffer is converted.
Sent to At this time, the print data is shifted by the amount of the pixel shift of the post-strike head. That is, the print data after the head of C is set from the second nozzle of the head. Similarly, M
Is set from the third nozzle, and Y is set from the fourth nozzle. The print data shifted in this way is the DR of HEAD 504.
Driven by the IVER 503, printing is performed on recording paper.

Next, a specific recording method in this embodiment will be described with reference to the drawings. FIG. 1 is a diagram for explaining a case where print data for two line widths is recorded. In the figure, the squares representing pixels are images on recording paper, and the numbers in the figures indicate the nozzle numbers of the print heads that print the pixels.
In this embodiment, the print head has first to eighth nozzles.

In the first scan, the K head, which is the first hit, performs staggered printing using the lower half (for four pixels) of the print head. At this time, printing by the trailing ink head is performed by shifting pixels by the amount shifted in the recording paper conveyance direction. In the case of C next to K, in this example, reverse staggered printing is performed using the sixth to eighth nozzles by shifting one pixel. Hereinafter, similarly, M is the seventh to eighth.
The staggered printing is performed by the nozzles, and the inverted staggered printing is performed by using only the eighth nozzle for Y. In the second scan, K is zigzag, C is zigzag, M is zigzag, and Y is zigzag. In this way, the printing is performed up to the sixth scan, and printing for all two lines is completed.
The K head does not print in the sixth scan.

FIG. 2 is a diagram showing an image forming state when the recording operation as shown in FIG. 1 is performed over a plurality of lines. The horizontal direction is the main scanning direction, and the upward direction is the recording paper transport direction. Also, the ink arrangement for each color is shown using a fill pattern corresponding to each color print head.
In the case of the present embodiment, the line feed width between the scans is half the nozzle width of the print head row. Print head row 1Y, 1M,
Reference numerals 1C and 1K denote a print area for each ink for each scan by slightly deviating in the horizontal direction for each scan. Therefore, the print start position does not always deviate for each scan. or,
The arrangement of each color ink on the recording paper is such that the post-strike ink is written on the pre-strike ink, but this is simplified for the sake of illustration. The actual arrangement of ink on the recording paper is shown in FIG.
As described above, the post-strike ink penetrates into the lower layer of the pre-strike ink.

According to this embodiment, as in the case of FIG. 15, since the connecting portion is different for each color, it is possible to prevent the generation of the mixed color connecting streak.

FIG. 4 shows a thinning method different from the above-described staggered reverse staggered method. Also in the case of this example, the print head is shifted one pixel at a time in K, C, M, and Y in the recording paper transport direction in the printing order. This thinning method is basically 2 × 2
A pixel is divided into two by a diagonal line, and an adjacent 2 × 2 pixel is arranged in an inverted manner. Also in this case, printing is performed for the width of two lines by printing from the first scan to the sixth scan in each ink color as in the case of FIG.

FIGS. 3 and 5 show how the mixed color portions G and B are formed in the case of the one-pixel shift described above. In the case of mixed color B printing, the hue of CM and the hue of MC occur alternately,
By using the fine recording method, it is possible to prevent color mixing and color unevenness, and to prevent the uneven color of the head, and to prevent a color-mixing streak by shifting the connecting portion with each color.

In the case of this embodiment in which the adjacent head is shifted by one pixel, the thinning pattern differs from that of the adjacent head. In the case of a mixed color shifted by two pixels, such as C and Y, the thinning pattern is the same. That is, if the number of shift nozzles is odd, the thinning pattern is different, and if the number of shift nozzles is odd, the pattern is the same. First,
Mixed color B of M starting with zigzag printing and C starting with reverse zigzag printing
In the case of (1), the printing order of M and C is alternately changed, and the pixels of C first hit and M second hit are continuously repeated periodically (CM continuous portion in FIG. 3). In the case of CM, the color of the first hit C is dominant, and in the case of MC, the first hit M shows a dominant hue. Such a periodic pattern has a relatively large spread on plain paper.
Since the inks on the pixels MC and MC are mixed with each other, there is relatively no problem visually, but on paper having a coat layer with little bleeding, this periodic change in hue may be confirmed as streaks or patterns. Connect. Looking at the generation of the mixed color G by C and Y shifted by two pixels (the mixed color G portion in FIGS. 3 and 5 shows a state in the middle of printing so that the fine recording method can be easily understood). Is always formed by C first strike and Y second strike G, and the hue does not change.

Therefore, in the case of the even nozzle pitch shift, this is a print head shift method that can be used regardless of the bleeding performance of the recording medium or ink. FIG. 6 shows a case of even-number shift (shift by two pixels). This figure shows a print image when the print heads K, C, M, and Y are shifted by two pixels, as in the case of FIG. In this case, 7 for printing all 2 lines
One scan is required. FIG. 7 shows a mixed color B printing state in the case of a two-pixel shift.

As described above, all the pixels have the same hue after the C-first strike and the M-last strike. As described above, the fine recording method using even-numbered shifts can prevent variations in paper feed, color unevenness, ejection distortion, and the like, and can also prevent color mixing streaks that do not depend on the bleeding performance of ink or recording paper.

In the above embodiment, the fine recording method is based on 1/2 printing of the head width and 1/2 paper feed. However, in other cases, the fine recording method may be 1/4, 1/8 or the like. Is also enough.

In this embodiment, among the ink jet recording systems, an ink jet recording apparatus which forms flying droplets by using thermal energy and performs recording is described as an example. Regarding the configuration and principle, it is preferable to use the basic principle disclosed in, for example, US Pat. Nos. 4,723,129 and 4,740,796. This method can be applied to both the so-called on-demand type and the continuous type. In particular, in the case of the on-demand type, it is arranged corresponding to the sheet or liquid path holding the liquid (ink). By applying at least one drive signal for giving a rapid temperature rise exceeding each boiling point in accordance with the recording information to the electric heat exchanger being used, heat energy is generated in the electric heat converter and the recording head is driven. This is effective because film boiling occurs on the heat acting surface, and as a result, bubbles in the liquid (ink) corresponding to this drive signal one-to-one can be formed. By discharging the liquid (ink) through the discharge opening by the growth and contraction of the bubble, at least one droplet is formed. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of the liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable.

As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. still,
If the conditions described in US Pat. No. 4,313,124 of the invention relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of the discharge port, the liquid path, and the electric heat exchanger (linear liquid flow path or right-angle liquid flow path) as disclosed in the above-mentioned respective specifications, A configuration using U.S. Pat. No. 4,558,333 or U.S. Pat. No. 4,459,600, which discloses a configuration in which a thermal action is bent, may be used.

In addition, JP-A-59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electric heat exchanger for a plurality of electric heat exchangers, and absorbs pressure waves of thermal energy. A configuration based on JP-A-59-138461, which discloses a configuration in which an opening corresponds to a discharge unit, may be adopted.

Further, as a full-line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording apparatus, a combination of a plurality of recording heads as disclosed in the above specification is used. Either a configuration that satisfies the length or a configuration as one integrally formed recording head may be used.

In addition, a replaceable chip-type recording head that can be electrically connected to the apparatus main body and supplied with ink from the apparatus main body by being mounted on the apparatus main body.
Alternatively, the present invention is also effective when a cartridge type recording head in which an ink tank is provided integrally with the recording head itself is used.

It is preferable to add recovery means for the recording head, preliminary auxiliary means, and the like, since the effects of the present invention can be further stabilized. If these are specifically mentioned, capping means for the recording head,
Cleaning means, pressurizing or suction means, an electric heat exchanger or a separate heating element, or a preheating means using a combination of these means, and a preliminary ejection mode in which ejection is performed separately from recording can be performed to achieve stable recording. Effective to do.

In the above-described embodiment, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens at room temperature or is a liquid, or the above-described ink jet ink is used. In general, the temperature of the ink itself is controlled within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. What is necessary is just liquid thing.

In addition, the temperature rise due to thermal energy can be positively prevented by using it as energy for changing the state of the ink from a solid state to a liquid state, or solidified in a standing state to prevent evaporation of the ink. In some cases, the ink is liquefied by application of thermal energy according to the recording signal, and in any case, the ink is liquefied and ejected as a liquid ink. Such an ink having a property of being liquefied for the first time by heat energy may be used. In such a case, the ink is held as a liquid or solid substance in the concave portion or through hole of the porous sheet as described in JP-A-54-56847 or JP-A-60-71260. It is good also as a form which opposes an electric heat exchanger in the state performed. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, as a form of the recording apparatus according to the present invention, an image output terminal of an information processing device such as a word processor or a computer as described above may be combined with a reader or the like in addition to a unit provided integrally or separately. And a facsimile machine having a transmission / reception function.

The present invention can be applied not only to the ink jet system using thermal energy but also to an ink jet system using a piezo element or the like.

[0044]

As described above, according to the present invention, the printing element array of each color is divided into a plurality of blocks, and the printing of a predetermined area on the printing material is mutually complemented by a plurality of main scans using different blocks. The recording is completed by recording a thinned image having the following relationship, and the connecting portion of a predetermined area continuous for each color is made different. It is possible to prevent the occurrence of connecting streaks and record a high-quality color image.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating printing of an embodiment using a staggered or inverted staggered thinning pattern according to the present invention.

FIG. 2 is a diagram illustrating printing according to the first embodiment of the present invention.

FIG. 3 is a diagram illustrating a printing state of a mixed color portion in the first embodiment.

FIG. 4 is a diagram illustrating a printing state of an embodiment using another thinning pattern.

FIG. 5 is a diagram illustrating a printing state of a mixed color portion by the printing shown in FIG. 4;

FIG. 6 is a diagram illustrating a printing state when adjacent print heads are shifted by an even number of pixels.

FIG. 7 is a view for explaining a printing state of a mixed color portion by the printing shown in FIG. 6;

FIG. 8 is a perspective view of a color inkjet recording apparatus to which the present invention can be applied.

FIG. 9 is a block diagram showing a control unit of the color inkjet recording apparatus shown in FIG.

FIG. 10 is a diagram illustrating an ideal printing state of the ink jet printer.

FIG. 11 is a diagram illustrating a printing state of an inkjet printer having uneven density.

FIG. 12 is a diagram illustrating fine recording.

FIG. 13 is a diagram illustrating a printing state by fine recording.

FIG. 14 is a diagram for explaining a conventional method for preventing a color mixing streak.

FIG. 15 is a view for explaining the print image of the conventional example shown in FIG.

FIG. 16 is a diagram showing an arrangement of pixel units in the conventional example shown in FIG.

FIG. 17 is a view for explaining a conventional method of preventing a color-mixing streak.

FIG. 18 is a view for explaining color mixing streak development.

FIG. 19 is a view for explaining color mixing and streak development.

FIG. 20 is a diagram for explaining color mixture streak development.

FIG. 21 is a diagram for explaining conventional printing.

[Explanation of symbols]

 1Y, 1M, 1C, 1K Print head row 6, 7 Belt 8 Carriage drive motor 9 Ink tube 10Y, 10M, 10C, 10K Ink cartridge 103 Recording paper 201 Carriage

Continued on the front page (72) Inventor Masaya Uetsuki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Fumihiro Goto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Atsushi Arai 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-3-224746 (JP, A) JP-A-1-208143 (JP, A (58) Fields surveyed (Int. Cl. ⁷ , DB name) B41J 2/21 B41J 2/13

Claims (10)

(57) [Claims] 1. A printing method in which a plurality of printing element arrays for ejecting inks of different colors are arranged in a main scanning direction relative to a printing material in a direction different from the printing element array direction. An ink jet recording method for recording a color image on the recording material by discharging a plurality of different color inks from a unit, wherein a recording element array of each color of the recording unit is divided into a plurality of blocks in the recording element array direction. A recording step of completing the recording of a recording area extending in the main scanning direction on the recording material by recording a thinned-out image having a complementary relationship with each other using the divided different blocks in each of a plurality of main scans. And a sub-scanning step of sub-scanning the recording unit and the recording material in the recording element row direction by an amount corresponding to the length of the divided one block for each main scan. The position of the boundary portion extending in the main scanning direction of the recording area formed by main scanning of the recording elements at both ends of each block of the recording element row of each color is different for each color in the sub-scanning direction. Characteristic ink jet recording method. 2. The ink jet recording method according to claim 1, wherein the recording element rows of the respective colors are arranged so as to be shifted by a predetermined amount in the recording element row direction. 3. The ink jet recording method according to claim 2, wherein the predetermined amount is an integral multiple of a recording density of the recording unit. 4. The ink jet recording method according to claim 3, wherein the integral multiple is an even multiple. 5. The ink-jet recording method according to claim 1, wherein the recording means discharges the ink by causing a state change in the ink by using thermal energy. 6. The printing method according to claim 1, wherein a printing unit having a plurality of printing element arrays for ejecting inks of different colors is main-scanned relative to a printing material in a direction different from the printing element array direction. An ink jet recording apparatus that records a color image on the recording material by discharging a plurality of different color inks from a unit, wherein a recording element array of each color of the recording unit is divided into a plurality of blocks in the recording element array direction. And recording control for completing recording of a recording area extending in the main scanning direction on the recording material by recording thinned-out images complementary to each other using the divided different blocks in each of a plurality of main scans. Means, and sub-scanning means for sub-scanning the recording material in the recording element row direction by an amount corresponding to the length of the divided one block for each main scan. The position of the boundary portion extending in the main scanning direction of the recording area formed by main scanning of the recording elements at both ends of each block of the recording element row of each color is different for each color in the sub-scanning direction. Characteristic inkjet recording device. 7. The ink jet recording apparatus according to claim 6, wherein the recording element rows of the respective colors are arranged to be shifted by a predetermined amount in the recording element row direction. 8. An ink jet recording apparatus according to claim 7, wherein said predetermined amount is an integral multiple of a recording density of said recording means. 9. The ink jet recording apparatus according to claim 8, wherein the integral multiple is an even multiple. 10. An ink jet recording apparatus according to claim 6, wherein said recording means discharges the ink by causing a state change in the ink by using thermal energy.