JP2003341036A - Inkjet recording method and recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce streaks at joints achieved in one path printing. <P>SOLUTION: The number of recording data (number of dots to be plotted) only near the joint is counted. When the number is larger than a specified dot number, a plurality of recordings by dividing the recording to a plurality of the number of times are carried out instead of normal recording of carrying out one recording scanning at a time. <P>COPYRIGHT: (C)2004,JPO

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 and a recording apparatus capable of obtaining a high quality image on a recording material.
The present invention relates to an inkjet recording method and a recording apparatus that perform printing by a pass or a plurality of passes.

The present invention can be applied to all devices using recording media such as paper, cloth, leather, non-woven fabric, OHP paper, and metal. Specific applicable equipment includes office equipment such as printers, copying machines, and facsimiles, and industrial production equipment.

[0003]

2. Description of the Related Art In recording on a recording medium by a recording device, there is an increasing need for users who want to print at high speed.

When performing printing with an emphasis on speeding up, it is effective to reduce the number of passes in multi-pass printing used for realizing high image quality. Here, the number of printing passes means the number of carriage scans required to complete one line.

This is because the number of ejection ports of the recording head is a constant value, so that the larger the number of passes is, the smaller the paper feed amount is, and conversely, the smaller the number of passes is, the paper feed is performed once. This is because the amount of can be increased. For example, if it is possible to print in one pass where printing is currently being performed in two passes, the speed can be simply doubled.

That is, the smaller the number of passes, the larger the paper feed amount per one time, and the fewer the number of times the carriage is scanned, the shorter the time required to print one sheet.

[0007]

However, since the recording head having a plurality of ejection ports for ejecting the recording liquid is operated in the direction perpendicular to the arrangement direction of the ejection ports to perform printing, there is one problem.
When printing is attempted in a pass, a band-shaped image area (band) as shown in FIG. 11 is formed by one scanning.

When printing is performed in one pass, one band is formed by one scan, so the duty of the recording ink ejected onto the recording medium at one time is a multi-image forming image by a plurality of scans. More than pass printing. For this reason, although the degree of difference varies depending on the recording medium and the properties of the recording liquid, black stripes due to bleeding of the recording liquid on the recording medium in a portion having a high print duty in one-pass printing are remarkable. Become.

This is a so-called side-by-side head in which recording heads for ejecting a plurality of different recording inks (cyan, magenta, yellow, etc.) are arranged in parallel in a direction orthogonal to the main scanning direction. In the configuration, the adverse effect is even greater. This is because the connecting position of each color occurs at the same place. A schematic view of the recording heads arranged side by side is shown in FIG.

Further, the band to be printed first (see FIG. 11, first)
If there is a delay between the band caused by scanning and the band to be printed next (the band caused by the second scanning in FIG. 11) due to, for example, a head temperature rise or a discharge smear, this 2 The time difference between scans is larger than the time difference in other parts. Due to the printing time difference thus generated, the black stripes at the boundary portion between the bands become stronger.

The black stripes that occur at the boundary between the bands as described above are also called "connecting stripes". If the "connecting stripes" occur, the print quality may be unacceptable for actual use. is there.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a recording apparatus capable of obtaining an image without a joining stripe in an ink jet recording apparatus. It is in.

[0013]

A recording apparatus that uses a recording head to eject recording ink onto a recording medium to perform printing, and can perform recording by one scan of the recording head.
Of the band data, the print data in the vicinity of the joint portion is divided into unit areas formed by a predetermined number of pixels, and an acquisition means for acquiring the number of data in each unit area and a predetermined threshold value. Setting means for setting a table, comparing means for comparing the value obtained by the acquiring means with the threshold value, control means for controlling the number of times of recording of each recording operation based on the result of the comparing means, Selection means for selecting a mask pattern to be used for printing according to the number of printings controlled by the control means.

The number of data per unit area acquired by the acquisition means may be set by dividing the sum of the data of each color by the number of pixels in the unit area and setting a threshold value for this. Or, from the number of data for each color, determine what hue the unit area of interest is,
Different thresholds may be set for each hue event.

According to the above arrangement, the number of print data (the number of dots to be drawn) near the connection is counted, and if the number of print data is larger than the specified number of dots (which is the threshold value), one print scan is performed once. Instead of the normal recording that is performed, a plurality of recordings that are recorded in multiple times are performed. As a result, in the high density portion, which is called so-called joining stripe, where image deterioration is likely to occur, the image is formed by scanning a plurality of times to reduce the occurrence of joining stripe, and in the low density portion where joining stripe hardly occurs, 1 High-speed printing is possible by printing by scanning once. In this way, it is possible to obtain a print result in which both print quality and speed are compatible depending on the image to be printed.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below by taking a serial printer having a plurality of recording heads as an example.

In one embodiment of the present invention, the vicinity of the joint portion of the data for one band is divided into unit areas, the number of dots of each color is counted for each area, and the sum is calculated for each unit area. The dot count value (or print duty) is set for each, and this count value is compared with a threshold value given in advance. As a result of the comparison, when it is determined that the dot count value is larger than the threshold value, the print mode is changed from 1 pass to 2 pass and printing is executed.

As described above, the number of print data in the vicinity of the connection (the number of dots to be drawn) is counted, and if the number of dots is larger than the specified number of dots (which is the threshold value), the print data is not printed at one time. If you record it in two steps,
An output result with less so-called connecting stripes can be obtained at higher speed depending on the image to be printed.

(Embodiment) An embodiment of the present invention will be described in detail below with reference to the drawings. In each drawing, elements indicated by the same reference numerals are the same or corresponding elements.

(First Embodiment) The first embodiment of the present invention relates to a recording system in which a plurality of recording heads print on a recording medium using recording ink to form an image.

FIG. 1 is a schematic perspective view showing the essential structure of an embodiment of an ink jet recording apparatus to which the present invention is applied.
In FIG. 1, a plurality of (four) head cartridges 1
A, 1B, 1C, and 1D are exchangeably mounted on the carriage 2. Each of the cartridges 1A to 1D is provided with a connector for receiving a signal for driving the recording head unit. In the following description, when all or any one of the recording units 1A to 1D is referred to, it is simply referred to as the recording unit (recording head or head cartridge) 1.

The plurality of cartridges 1 respectively record with different color inks, and the ink tanks thereof store different inks such as cyan, magenta and yellow. Each recording means 1 is mounted on a carriage 2 so as to be positioned and exchangeable, and a connector holder (electrical connection portion) for transmitting a drive signal or the like to each recording means 1 via the connector on the carriage 2. Is provided.

The carriage 2 is guided in the moving direction along the guide shaft 3 installed in the main body of the apparatus in the main scanning direction. The carriage 2 is driven by the main scanning motor 4 via the motor pulley 5, the driven pulley 6, and the timing belt 7, and its position and movement are controlled. The recording material 8 such as paper or plastic thin plate is 2
By the rotation of the pair of conveying rollers, the sheet is conveyed (paper feeding) through a position (recording unit) facing the ejection port surface of the recording head 1. The back surface of the recording material 8 is designated by a platen (not shown) so that a flat recording surface can be formed in the recording portion. In this case, each of the cartridges 1 mounted on the carriage 2 is held such that the ejection port surface thereof projects downward from the carriage 2 and becomes flat with the recording material 8 between the two pairs of the transport rollers. There is.

The recording head 1 is an ink jet recording means for ejecting ink by utilizing thermal energy,
It is provided with an electrothermal converter for generating heat energy. Further, the recording head 1 uses the pressure change caused by the growth and contraction of bubbles due to film boiling generated by the thermal energy applied by the electrothermal converter to eject ink from the ejection port for recording. .

FIG. 2 is a schematic perspective view partially showing the main structure of the ink ejection portion 13 of the recording head 1.
In FIG. 2, the recording material 8 and a predetermined gap (about 0.5 to 2
A plurality of ejection openings 22 are formed at a predetermined pitch on the ejection opening surface 21 facing each other with a space of about [mm]).
An electrothermal converter (heat-generating resistor, etc.) 25 is disposed along the wall surface of each flow path 24 that communicates 3 with each discharge port 22 to generate energy of the ink discharge amount. In this example, the recording head 1 is mounted on the carriage 2 in such a positional relationship that the ejection ports 22 are arranged in a direction intersecting the scanning direction of the carriage 2. In this way, recording is performed by driving (energizing) the corresponding electrothermal converter 25 based on the image signal or the ejection signal to cause the ink in the flow path 24 to film-boil and eject the ink from the ejection port 22 by the pressure generated at that time. The head 1 is configured.

FIG. 3 shows a block diagram of a schematic configuration example of a control circuit in the ink jet printing apparatus.

In FIG. 3, the controller 100 is a main control unit, for example, a CP in the form of a microcomputer.
It has a U 101, a ROM 103 storing fixed data such as programs and required tables, and a RAM 105 having an area for developing image data, an area for work, and the like. The host device 110 is a supply source of image data (a computer that performs creation and processing of data such as images related to printing, and may be a reader unit for image reading). Image data, other commands, status signals and the like are transmitted to and received from the controller 100 via the interface (I / F) 112.

The operation unit 120 is a switch group that receives an instruction input by an operator, and has a power switch 122, a switch 124 for instructing printing start, a recovery switch 126 for instructing activation of suction recovery, and the like.

The head driver 140 is a driver for driving the ejection heater 25 of the print head 1 according to print data and the like. The head driver 140 is
In addition to a shift register for aligning print data in correspondence with the position of the discharge heater 25, a latch circuit for latching print data at appropriate timing, a logic circuit element for operating the discharge heater in synchronization with a drive timing signal, and dot formation position adjustment. In order to do so, it has a timing setting unit or the like that appropriately sets the drive timing (ejection timing).

The print head 1 includes a sub heater 14
Two are provided. The sub-heater 142 adjusts the temperature for stabilizing the ink ejection characteristics, and is formed on the print head substrate at the same time as the ejection heater 25 and / or is attached to the print head main body or the head cartridge. Can be

The motor driver 150 is the main scanning motor 1
The sub-scanning motor 162 is a motor used to convey (sub-scan) the print medium 8, and the motor driver 160 is the driver.

FIG. 4 is a flow chart showing the processing from print data reception to printing.

First, in step 401, print data is received from the outside, and in step 402, print data for one band is prepared. With the print data of the prepared band, it is checked whether all the data are finished (step 403). If it is finished, step 40
The data prepared in step 2 (hereinafter, the data analyzed in step A is referred to as “data A”) is printed in one pass (step 404) and the sheet is ejected (step 417).

If it is determined in step 403 that the print data is to continue, the process proceeds to step 405.
Here, an area of 60 pixels (main scanning direction) * 16 pixels (sub scanning direction) at the bottom of the band of each color (the configuration diagram of the recording head used in this embodiment is shown in FIG. 12) (hereinafter referred to as unit area) A value obtained by counting the number of dots and dividing the sum by the size of the unit area (960 in this embodiment) (hereinafter referred to as “dot count value”).
Is written) and a threshold value set in advance. To supplement the dot count value, "the dot count value is 1" means that one dot exists in one pixel, and if it is 2, it means that two dots exist in one pixel. Is shown.

Here, FIG. 5 is shown in order to explain the unit area.

The drawing is for the case of a recording head having 256 nozzles in the sub-scanning direction. Main scanning direction 2880
Pixels (360 DPI * 8 inches) are divided into 48 blocks. The magnitude of the dot count value and the threshold value obtained by calculation from each of these blocks is determined (step 40).
5).

If the result of this determination is that none of the blocks exceed the threshold value, step 4
The process proceeds to 06, the data 402 is printed in one pass, and the paper feed for one band is performed (step 407), and step 402
Go to.

On the other hand, if it is determined in step 405 that one of the blocks has a dot count value exceeding the threshold value, the data 402 is stored in the upper 128 nozzles of the 256 nozzles using the 1-pass mask. All of the lower 128 nozzles are printed using a mask for two passes (step 408).

When printing is performed, 1/2 band (128
Paper feeding for pixels is performed (step 409), and data for one band corresponding to the print position is prepared (step 4).
10). The data 410 prepared here is the data 40
It overlaps with 2 by half a band.

In step 411, it is checked whether or not the data 410 has ended, and if it has ended, the data 410 is the data for the upper 128 nozzles in the mask of 2 passes 2 and the data for the lower 128 nozzles is 1 Printing is performed using a pass mask (step 412), and the paper is ejected (step 41).
7), and process.

If the print data still continues, dot count is performed as in step 405 (step 4
13) If the dot count value is smaller than the threshold value, the data 410 is printed using the data for the upper 128 nozzles using the mask for 2 passes and the mask for the lower 128 nozzles using the mask for 1 pass (step 415), and 1 is printed. / 2 band (128 nozzles) paper feed (step 416), and step 40
I will return to 2.

If the dot count value in step 413 exceeds the threshold value, the data 410 is incremented by 1.
The data for 28 nozzles is printed using the mask for 2 passes 2 and the data for the lower 128 nozzles is printed using the mask for 2 passes 1 (step 414), and the process proceeds to step 409.

Here, an example of the mask for one pass and the mask for two passes is shown in FIG.

The pattern shown in FIG. 6 is a part of it.
The size is cut out into two vertical pixels and two horizontal pixels.
This is a mask pattern used by multiplying this vertically 64 times and horizontally 64 times.

FIG. 6 (a) shows the mask for one pass, FIG. 6 (b) shows the mask for two pass 1, and FIG. 6 (c) shows the mask for two pass 2. . This mask shows that the data in the shaded areas of the mask is printed, and the blank pixels are not printed. Use both 2-pass 1 and 2-pass 2 masks. You can print all print data with.

In this embodiment, the mask is simplified to form a zigzag pattern, but the dot arrangement and the size of the mask are not particularly limited to this.

Here, one example will be considered more specifically.

FIG. 7 shows a diagram used for the explanation.

FIG. 6A shows a state of data to be analyzed. For simplicity, the unit area for dot counting is 5 blocks in the main scanning direction, and the dot count value of each unit area is shown. FIG. 6B is a diagram showing a printing state at that time. It should be noted that in each of the drawings, the even band and the odd band are laterally offset for easy viewing.

Further, (c) to (e) are shown to supplement the printing state of FIG.

The pattern shown in (c) indicates that printing is performed using a 1-pass 1 mask.
The pattern shown in (d) is a 2 pass 1 mask,
The pattern shown in (e) indicates that printing is performed using a 2-pass 2 mask.

First, in the first band, if the threshold value is set to 1.6, all dot count values are within the threshold value.
This band information is printed in one pass using the mask for one pass shown in FIG. 7 (c). In the next one band, that is, the band shown in FIG. 7A, since the dot count value in the third unit area from the left exceeds the threshold, the upper 128 nozzles (first band side nozzle, The data for the "upper nozzle" below is printed using the 1-pass mask, and the data for the lower 128 nozzles (hereinafter referred to as the "lower nozzle") is printed using the 2-pass mask 1 Paper feed for 2 bands (128 nozzles) is performed.

Then, the data of the next band (third band) is analyzed. At this time, the data partially overlapped with the second band is analyzed. 2 nozzles are used to print data
The pass 2 mask is used, and the lower nozzle has a dot count value larger than the threshold value. Therefore, the pass 2 mask is used.

Although it is the fourth band, similarly to the third band, data analysis is performed in a state where the third band, which is the immediately preceding band, overlaps by 128 nozzles of all nozzles. As a result, since there is no dot count value that exceeds the threshold value, the upper nozzle prints using a 2-pass 2 mask and the lower nozzle prints using a 1-pass mask, and paper feed for one band is executed.

Finally, the data analysis of the fifth band is performed. Since there is no subsequent data in the input data shown in FIG. 7, both the upper and lower nozzles are printed using the 1-pass mask, the paper is discharged, and the processing is ended.

As described above, since the pass mode can be changed by the data processing of the small area in the vicinity of the joint portion (that is, the nozzle end portion) of one band, the processing load is small and the speed is as high as one pass. Due to the importance placed on it, the processing can be sufficiently performed even when the time devoted to the processing is short.

According to the control method of the present embodiment, if there is more print data than the prescribed number of dots (which is the threshold value), the number of print data near the connection (the number of dots to be drawn) causes the print The data can be recorded in two scans instead of being recorded in one scan.

(Second Embodiment) The second embodiment of the present invention is, like the first embodiment, a recording method in which a plurality of recording heads print on a recording medium using recording ink to form an image. It is about.

The structure of the recording apparatus used in this embodiment is the same as that of the first embodiment described above.

FIG. 8 shows a flowchart of threshold value selection in this embodiment.

The nozzle structure of the head used in this embodiment is shown in FIG.

The reason why the black only is increased with respect to the nozzles of other colors is to increase the speed when printing only black. In the case of such a configuration,
When printing color data, all black nozzles are not used, and the upper 256 nozzles (nozzle K51
9-nozzle K264) only is used. The appearance of the band formed by using such a nozzle is shown in FIGS.

(C) shows the case of printing only black data, and (d) shows the state of printing black and color mixed data.

To use the black nozzle in this way,
This is because there are only 256 color nozzles, and in order to suppress bleeding between black colors, the upper portion 256 is used for the black nozzles so that images are not formed at the same printing position for black and color by simultaneous scanning. I will do it.

FIG. 9 is an example showing the dot count values of cyan, magenta, and yellow in the unit area.

Here, the dot count value is cyan,
The reason why only the three colors of magenta and yellow are used and the value of black is not used is that black has a small print position in the same scan as color, and therefore has little effect on the connecting stripes.

FIG. 10 is an example of a threshold table for each hue.

As the threshold value selection processing, in step 81, the number of dots for each color of the unit area is acquired, and then sorted in descending order of the number of dots (step 82), the second largest one and the second largest one. By subtracting the third, the primary color and secondary color components are known. For example, when there is an input as shown in FIG. 9, the primary color component is magenta and the secondary color component is red. The smallest one (Fig. 9
In, the cyan value is the tertiary color (UC: under color) (step 83).

The size of the calculated number of dots of the primary, secondary and tertiary colors is judged, and the hue showing the largest value is the hue of the unit area to be processed now (step 84).

After the hue of the unit area of interest is determined in this way, a threshold value given in advance as shown in FIG. 10 is selected for each obtained hue, and this and the determination of the dot count value are determined. Decide to do.

The threshold value judging means for judging the hue of each unit area and selecting the threshold value as described above is used in step 40 of the first embodiment.
5 and step 413, and the processing from print data reception to printing is the same as in the first embodiment.

In this embodiment, cyan, magenta, and yellow are used as the dot count values,
Although the black count value is not used, it is of course good to use it.

According to the control method of the present embodiment, a threshold value is set for each hue for the same imprinting (dot count value), as compared with the case of a constant threshold value designed to match the one that is most prone to streaks. Since it can be set, one pass can be selected depending on the hue, and the selection of one pass and two passes can be made more compatible with the data of the input image.

In the first and second embodiments, the size of the unit area is 60 pixels (main scanning direction) * 16 pixels (sub scanning direction), but it is necessary to pay particular attention to this size. There is no. It is desirable that the size of the unit area is determined by various factors such as the load of processing the data and the output resolution.

Further, regarding the portion for performing dot counting, in the first and second embodiments, for example, as shown in FIG. 7, only the lower end portion of the previous scan is targeted, but the present invention is not limited to this. . For example, for the joint,
The dot count value may be calculated at the upper end of the subsequent scanning and the processing may be performed based on this, or the processing may be performed based on the results of both.

The part for performing such dot counting is
Needless to say, it is desirable to perform processing by using a portion that seems to be optimal depending on the combination of the recording medium used and the recording ink.

In the threshold value judgment at the time of changing the pass mode, in the first embodiment, if any one of the blocks has a value larger than the threshold value, the pass mode is changed to 2 pass. However, this does not particularly need to be particular about this method, and the pass mode may be changed when, for example, two or more blocks exceeding the threshold value continue.

Further, since the connecting streak is caused by the bleeding of the recording ink on the recording medium, the bleeding degree of the recording ink becomes large and the connection becomes more severe (more conspicuous) in, for example, a hot and humid environment. Therefore, it is effective to have a plurality of thresholds for changing the path mode so that the thresholds can be changed according to the external environment used.

Although the recording inks used are cyan, magenta, yellow, and black in the configuration of the above-described embodiment, the present proposal should be used in a system using a so-called regular ink diluted photo ink. You can

When the amount of data to be printed exceeds a certain size as in the present invention, the pass mode is changed,
When the number of passes is increased to perform printing, the temperature of the head during printing is increased, and the recording medium is rubbed between the ejected recording medium and the recording medium on which printing is performed. It is also effective in avoiding stains on the paper and deterioration of print results (paper smear).

(Others) In particular, the present invention is provided with a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for ejecting ink, especially in the ink jet recording system. The present invention brings about excellent effects in a recording head and a recording apparatus of the type in which the state of ink is changed by the heat energy. This is because such a system can achieve high density recording and high definition recording.

Regarding the typical structure and principle thereof, see, for example, US Pat. Nos. 4,723,129 and 4740.
What is done using the basic principles disclosed in 796 is preferred.

This system 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 corresponds to a sheet or liquid path holding a liquid (ink). Heat energy is generated in the electrothermal converter by applying at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding each boiling to the electrothermal converters arranged in the same manner. Sir,
This is effective because film boiling is caused on the heat-acting surface of the recording head, and as a result bubbles can be formed in the liquid (ink) that correspond one-to-one to this drive signal. The liquid (ink) is ejected through the ejection openings by the growth and contraction of the bubbles to form at least one droplet. It is more preferable to make this drive signal into a pulse shape, because the bubble growth and contraction are immediately and appropriately performed, so that the ejection of the liquid (ink) with excellent responsiveness can be achieved. As the pulse-shaped drive signal, U.S. Pat. Nos. 4,463,359 and 4,434 are used.
Those as described in 5262 are suitable. If the conditions described in US Pat. No. 4,313,124 of the invention relating to the rate of temperature rise on the heat acting surface are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the discharge port and the liquid path electrothermal converter as described in the above-mentioned specifications (straight liquid flow path or right-angled liquid flow path). U.S. Pat. No. 4,558,333 and U.S. Pat. No. 44, which disclose a configuration in which a heat acting portion is arranged in a bending region.
The structure using the specification of No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy is discharged. The effect of the present invention is effective even if the configuration based on Japanese Patent Laid-Open No. 59-138461, which discloses the configuration corresponding to each section, is employed. That is, according to the present invention, recording can be surely and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full line type recording head having a length corresponding to the maximum width of a recording medium which can be recorded by the recording apparatus. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads or a configuration as one recording head integrally formed.

In addition, even in the case of the serial type as in the above example, the recording head fixed to the main body of the apparatus or the electrical connection to the main body of the apparatus and the ink from the main body of the apparatus by being attached to the main body of the apparatus. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is integrally provided in the recording head itself is used.

Further, as the constitution of the recording apparatus of the present invention, it is preferable to add the ejection recovery means of the recording head, the preliminary auxiliary means and the like because the effects of the present invention can be further stabilized. Specific examples thereof include preheating for heating the recording head by using a capping unit, a cleaning unit, a pressurizing or suctioning unit, an electrothermal converter or a heating element other than this, or a combination thereof. A preliminary ejection means for performing ejection different from the means and the recording can be used.

Regarding the type and number of recording heads to be mounted, for example, only one is provided corresponding to a single color ink, or a plurality of inks having different recording colors and densities are supported. A plurality of units may be provided. That is, for example, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but the recording head may be integrally configured or a plurality of recording heads may be used. The present invention is extremely effective for an apparatus provided with at least one of full-color recording modes by color mixing.

In addition, in the above-described embodiments of the present invention, the ink is described as a liquid, but an ink that solidifies at room temperature or higher and that softens or liquefies at room temperature may be used. Or, in the inkjet system, it is common to control the temperature of the ink itself within the range of 30 ° C. or higher and 70 ° C. or lower to control the temperature so that the viscosity of the ink is within the stable ejection range. Sometimes, a liquid ink may be used. In addition, the temperature rise due to thermal energy is positively prevented by using it as the energy of the state change of the ink from the solid state to the liquid state, or in order to prevent the evaporation of the ink, it is solidified and heated in the standing state. You may use the ink liquefied by. In any case, by applying thermal energy such as ink that is liquefied by applying thermal energy according to the recording signal and liquid ink is ejected, or that begins to solidify when it reaches the recording medium. The present invention is also applicable to the case where an ink having a property of being liquefied for the first time is used. In this case, the ink is disclosed in JP-A-54-56847 or JP-A-60.
As described in JP-A-71260, it may be configured to face the electrothermal converter in a state of being held as a liquid or a solid in the concave portion or the through hole of the porous sheet. 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, the ink jet system of the present invention is used as an image output terminal of information processing equipment such as a computer, a copying machine combined with a reader or the like, and a facsimile machine having a transmitting / receiving function. May be used.

[0091]

As described above, according to the present invention, printing is performed by selecting one pass or two passes of the print mode according to the amount of recording liquid ejected in the vicinity of the boundary between scans (bands). Since it can be performed, it is possible to suppress the decrease in the printing speed to the minimum and to alleviate the occurrence of the connection stripes.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing a schematic configuration of an inkjet recording apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view schematically showing a structure of a main part of the recording head shown in FIG.

FIG. 3 is a block diagram showing a schematic configuration of a control circuit in the ink jet printing apparatus according to the embodiment of the invention.

FIG. 4 is a flowchart showing a processing procedure in the first embodiment of the present invention.

FIG. 5 is a diagram illustrating dot count of print data according to the first embodiment of the present invention.

FIG. 6 is a schematic diagram illustrating a mask pattern in the first embodiment of the present invention.

FIG. 7 is an example of print data according to the second embodiment of the present invention.

FIG. 8 is a flowchart showing a processing procedure in a second embodiment of the present invention.

FIG. 9 is a schematic diagram showing an example of a dot count value in a unit area in the second embodiment of the present invention.

FIG. 10 is an example of a threshold value set for each hue in the second embodiment of the present invention.

FIG. 11 is a conceptual diagram for explaining bands and boundaries in the embodiment of the present invention.

FIG. 12 is a configuration diagram showing a conventional printed image.

[Explanation of symbols]

1, 1A, 1B, 1C, 1D head cartridge 2 carriage 3 Guide shaft 4 Main scanning motor 5 motors and pulleys 6 Driven pulley 7 Timing belt 8 Recording medium 9, 10, 11, 12 Conveyor rollers 13 Recording head section 21 Discharge port surface 22 Discharge port 23 Common liquid chamber 24 liquid channels 25 Electrothermal converter 100 controller 101 CPU 103 ROM 105 RAM 110 Host device 112 I / F 120 control panel 122 power switch 124 print switch 126 Recovery switch 140 head driver 142 Sub heater 150, 160 motor driver 123, 162 motor

Claims (9)

[Claims] 1. A recording apparatus for performing printing by ejecting recording ink onto a recording medium using a recording head, wherein a joint portion of one band of data that can be recorded by one scan of the recording head. Print data in the vicinity
An acquisition unit that divides the unit area formed by a predetermined number of pixels and acquires the number of data in each unit area, a setting unit that sets a predetermined threshold table, and a value obtained by the acquisition unit. A comparison means for comparing the threshold value given by the setting means, a control means for controlling the number of recording times of each recording operation based on the result of the comparison means, and a recording operation according to the number of recording operations controlled by the control means. And a selection means for selecting a mask pattern used for the recording apparatus. 2. The recording head for ejecting the recording ink is ejected by a different recording head for each color, and is arranged parallel to a direction orthogonal to the main scanning direction. Recording device. 3. The threshold value table set by the setting means is provided in plural according to at least the type of recording medium and recording environment, and can be used properly according to conditions. Recording device. 4. The printing operation controlled by the control means includes normal printing for performing one printing scan once and multiple printing for printing a plurality of times. The recording device according to item 3. 5. The comparison means compares the threshold value given by the setting means with the number of data pieces given by the acquisition means in order to obtain one band of data by the acquisition means in at least the main scanning direction and the sub-scanning direction. 5. The recording apparatus according to any one of 1 to 4, wherein any one of them is divided into a plurality of blocks to form a plurality of blocks, and the comparison is performed for each number of data given to each block. 6. The recording apparatus according to claim 1, wherein the number of data obtained by the obtaining means is the sum of the number of data obtained for each color. 7. The hue determining means for determining which hue the unit area of interest is in, from the number of data for each color acquired by the acquiring means, is provided. The recording device described. 8. The recording apparatus according to claim 7, wherein the threshold value table set by the setting means can set a threshold value for each hue that can be judged by the competition judging means. 9. The method according to claim 8, wherein the comparison unit selects a threshold value corresponding to the hue determined by the hue determination unit from the setting unit and compares the threshold value with the dot count value. Recording device.