JPH11198358A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out the recovery operation for a printing head and inform on the recovery operation and the like at the proper timing in the case uneven density or defective jetting is generated as a result of the deterioration of the printing head to be used with time in a printer in which printing is carried out by using the printing head jetting inks of different density of same family colors. SOLUTION: Prior to the printing of printed data, an area to be printed continuously in high concentration ink is extracted from actual printing data (S1), and the area is printed in ink of respective density (S3), and a printed pattern is read (S5) to decide the jet state of the printing head (S7). Based on the decision-result, the recovery operation for the printing head (S9) and the jet state are displayed (S11).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a printing apparatus which performs printing by applying a plurality of printing agents having similar colors, such as densities such as density, to a printing medium. Specifically, for example, an image reading unit is provided, and the ejection state of the plurality of printing elements is determined based on the reading result,
It performs recovery processing, displays the ejection state, and the like.

[0002]

2. Description of the Related Art Conventionally, an ink jet printing apparatus which discharges ink onto a print medium with a simple apparatus configuration and on demand has been known, and has recently been rapidly spread due to various advantages.

[0003] Such a printing apparatus uses an ink-jet print head in which a plurality of ink discharge ports are integrated and arranged in order to improve the printing speed.
Further, a printer having a plurality of such print heads is widely used for color printing. However, in such an ink jet printing apparatus, it is relatively difficult to modulate the diameter of a dot formed by ink for the main purpose of gradation expression, and the gradation is mainly expressed by pseudo halftone processing. ing. In addition, in order to output a higher quality image when using the pseudo halftone processing, a so-called multi-droplet method in which ink is multi-shot at substantially the same position on a print medium to express a gradation, or a similar color system is used. There has been proposed a method of expressing gradation using inks having different densities.

When an image is printed by an ink jet print head having a plurality of ink discharge ports, unevenness in density occurs due to a variation in ink discharge amount between ink discharge ports inherent in the print head, and unevenness. There was a problem of lowering. In order to deal with such a problem, correction data for correcting image data to be printed is measured by measuring data relating to density unevenness of each print head at the time of manufacturing an inkjet print head, and by driving conditions of the print head and image processing. Is written in a ROM or the like and mounted on a product.
However, this method may not be sufficient for uneven density and poor discharge due to variations in ink discharge amount or skew due to aging of the ink jet print head. An exchange has been made.

[0005]

In recent years, printing apparatuses have been provided with a function of displaying various error states, such as running out of paper, running out of ink, and jamming of paper, to prevent troubles. It is difficult to predict the occurrence of density unevenness and ejection failure, and it may occur during printing. In such a case, the operator outputs the print result and cannot confirm the occurrence until the output result is visually observed. In particular, in the case of a printing apparatus connected via a network, it is often installed at a position distant from the operator, and there has been a strong demand for improvement.

[0006] Further, some printing apparatuses perform printing by storing data in a memory buffer in order to reduce a load on a host apparatus which is a supply source of an image to be formed. In such a case, once printing is completed, it is common to erase the contents of the memory regardless of the quality of the print result, and if there is a problem with the print result, it is necessary to send data again, There was also a strong demand for improvement in this regard.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve these problems, and therefore, the present invention provides a method for applying a plurality of printing agents having different color tones to a print medium. In a printing apparatus that performs image formation using printing means, a driving means for driving the plurality of printing means based on print data corresponding to the plurality of printing means, and a printing agent having a predetermined color tone based on the printing data. An area separating unit that separates an area to be continuously printed, and a print data portion for causing printing with the printing agent of the predetermined color included in the area, using the printing agent of the plurality of colors. Means for driving the plurality of printing means by means of the driving means; Reading means for reading the information printed by the reading means, and judging means for judging the state of the plurality of printing means based on the read data read by the reading means. I do.

Here, it is possible to further comprise a recovery means for performing a recovery operation for improving the printing agent application state of the printing means based on the determination of the state by the determination means.

In addition, it is possible to further comprise a notifying means for notifying the state of the printing means based on the judgment of the state by the judging means.

In the above, a plurality of printing means are provided corresponding to printing agents having different densities for similar colors, and the printing agent having the predetermined color tone can have the highest density.

In this embodiment, prior to printing the print data on the print medium, the area is separated, the print data portion is printed on a corresponding area on the print medium, the reading is performed, and the determination is performed. Means can be provided.

In the above, the storage means for expanding the print data, the means for erasing the stored contents after the end of the printing operation, and the control of the erasing operation based on the judgment of the state of the printing means. Means can be further provided.

When arranging a plurality of images on the print medium, such as when outputting a medical image, it is determined whether the state of the printing means is good or not in a background area of the plurality of arranged images. Means for forming a printed pattern for performing the printing.

In the above, the printing means has an ejection port for ejecting ink as a printing agent applied to the print medium, and means for generating energy used for ejecting the ink. It can be.

Here, the means for generating energy used for discharging the ink may include an electrothermal converter for generating thermal energy in response to energization. The ink can be ejected from the ejection port toward the print medium by utilizing the film boiling generated in the ink by the applied thermal energy.

Further, an image forming system according to the present invention includes any one of the printing apparatuses described above, and means for supplying print data to the apparatus.

In this specification, "print" and "recording" are used not only when meaningful information such as characters and figures are formed, but also when images, patterns and patterns are widely formed on a medium (printing). If you do. Also,
"Print media" is not limited to paper used in general recording devices, but also widely accepts ink, processing agents, and other printing agents ejected by the head, such as cloth, plastic films, and metal plates. Shall also say.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings.

(First Example) FIG. 1 is a processing block diagram best representing the features of the first embodiment of the present invention. here,
Reference numeral 2 denotes one or a plurality of print heads provided according to the form of the ink jet printing apparatus. This print head has a so-called multi-nozzle head form having a plurality of ink ejection ports. In this example, it is assumed that four inkjet print heads that eject inks of the same color (for example, black (K)) with different densities are used.

Reference numeral 22 denotes a unit for scanning the print medium with respect to the print medium 7, and reference numeral 23 denotes a unit for conveying the print medium 22, and conveys the print medium 7 with respect to the print position of the print head 2.

Reference numeral 24 denotes a unit for reading a predetermined print pattern (test image) used for determining density unevenness and ejection failure (including non-ejection). In this embodiment, the head scanning unit 22 scans together with the print head 2. Is done.
Here, it is assumed that the light source includes a light source including a halogen lamp for irradiating the print medium 7 with light, and a reading unit including a lens and a CCD sensor provided for reading the reflected light. Reference numeral 25 denotes density unevenness measuring means, which will be described later in detail.

Reference numeral 26 denotes recovery means for performing capping to prevent evaporation of each ink discharge port of the print head 2, suction of ink, and cleaning of the discharge port forming surface. Reference numeral 27 denotes display means for displaying the measurement results of the density unevenness measurement means and other necessary messages, and may be composed of a liquid crystal panel or the like. Numeral 28 denotes control means, which performs measurement of density unevenness, display of measurement results, drive of print head recovery means, change of print head drive conditions, and other control related to printing by a microcomputer (CPU) or the like.

The ink used in this example is CI D
First density ink (D1) using irect Black 19
Has a dye concentration of 0.5 wt% and a second concentration of ink (D
2) The dye concentration is 1.0 wt%, the third concentration ink (D3) has a dye concentration of 2.0 wt%, and the fourth concentration ink (D4) has a dye concentration of 4.0 wt%. Glycerin, ethylene glycol,
Urea was added in an amount of 3.0 wt% each, and the balance was adjusted to 100 wt% by adding ion-exchanged water.

FIG. 2 is a schematic top view showing a configuration example of the ink jet printing apparatus according to the present embodiment. As shown in the drawing, a print head 2 is loaded on a carriage 1 which is a component of the head scanning means 22 for each density of ink. Also, each print head 2 has a 6
It is assumed that there are four ink ejection ports. In the present embodiment, as described above, four print heads 2 are used, and the first density ink (D
1) A second concentration ink (D) having a dye concentration of 1.0 wt%
2), a third density ink (D
3) a fourth density ink (D
4) are respectively discharged. A drive signal and other control signals are transmitted to these print heads 2 via a wire bundle 4. In addition, the conductor bundle 4 includes a light source and C
It also supplies power to the CD and transmits image signals from the CCD.

The carriage 1 on which the above-described print head is mounted is slidably connected to the two guide rails 5, and the driving force of the carriage driving motor 8 is transmitted via the belt 6 in the drawing. A series of main scans in which scanning is performed in the X direction and in the opposite direction -X can be performed. Further, a paper feed motor (not shown) conveys a print medium 7 such as print paper in the Y direction in the figure and performs sub-scanning, whereby an image is printed on the print medium 7 by each ink ejected from each print head 2. Printing can be performed sequentially.

The print medium 7 is intermittently fed by the print width of the print head 2, and while the print medium 7 is stopped, the print head scans in the X direction or the -X direction and discharges ink in accordance with an image signal. I do.

A reading unit 29 is arranged in parallel with the print head 2 on the carriage 1, and scans in the X direction or the −X direction to read a test image printed on the print medium 7. The test image and its reading method will be described later in detail.

D1 ink, D2 ink, D3 ink and D4 ink are supplied to each print head 2 on the carriage 1 from an ink tank 3 mounted at another place via an ink supply pipe 11. At one end of the moving range of the carriage 1, a print head cleaning mechanism 10 as a recovery means is provided, which caps each ink ejection port of each print head 2 and, in this capped state, prints ink. In addition to performing the suction operation, a wiping operation for cleaning the ejection port forming surface of the print head by wiping with a blade is performed.

The print head may be in the form of a cartridge comprising an ink tank containing ink and a print head 201 for discharging ink. In this example, the head is provided with a total of four inks having different densities corresponding to the black ink, but the types of colors and densities (hereinafter referred to as “color tone”) are not limited to this. Of course, a plurality of required inks can be prepared.

The print head or the ink tank may be completely integrated so that the head cartridge can be replaced when the ink remaining in the ink tank is exhausted. Alternatively, the ink tank alone may be detached so that it can be replaced. Alternatively, in addition to integrating them, such as those described above, ink tanks may be provided separately in other portions of the apparatus, and ink may be supplied to the print head by communicating the two with a tube or the like. Good. Further, in this embodiment, if inks with different densities are desired, ink tanks containing the respective inks can be used as in this example.For example, only the ink tank itself that contains the dark ink is prepared. However, a means for appropriately thinning the dark ink in the ink supply path to the head for discharging the light ink may be added. In addition, instead of providing a head cartridge for each color tone of ink as in the illustrated example, it is also possible to use an integrated printing means having an ejection portion capable of ejecting inks of predetermined plural colors.

FIG. 3 is a schematic perspective view showing the structure of the print head and the reading unit in this embodiment.
It is shown upside down. As shown in this figure, the reading unit 29 is mounted on the carriage 1 together with the print head 2, and reads an image by sliding on a guide rail. The reading unit 29 includes a light source 30 for illuminating a test image, a lens 31 for forming a test image on a photoelectric conversion element such as a CCD, and the like.

Next, in this embodiment, print image data is generated based on an input image in accordance with an image processing sequence as shown in FIG.

For example, the input image data is an 8-bit digital value in which the brightest portion of the captured image indicated by the input image data is "255" and the darkest portion is "0". In the distribution process SQ1, the image data for D1 ink, the image data for D2 ink, the image data for D3 ink, and the image data for D4 ink are generated according to the input image data by using the allocation table as shown in FIG. You.
Note that the sorting table shown in FIG.
The densities of the inks 2, D3, and D4 on the print medium are measured, and values corrected based on the densities are stored as respective density data.

Each image data for ink generated by the sorting process SQ1 is binarized by a binarizing process SQ2 using a dither matrix or the like, and D1, D2, D3,
Each image data binarized for D4 is obtained. In this example, it is assumed that the ink is ejected when the signal obtained as a result of the binarization is “0”, and that the ejection is not performed when the signal is “1”.

Further, in the present embodiment, an area in which ink with the highest density is continuously printed is extracted in accordance with the image processing sequence shown in FIG. 6 to create test image data.

From the image data for the ink D4 having the highest density, the number of ejection ports of the print head is 64 in the width in the sub-scanning direction.
The ink is continuously ejected over a larger number of pixels, and the ink is continuously ejected over a width (100 pixels in this example, which will be described later) that can be read by the reading unit in the main scanning direction. Is extracted.

In this example, the image data for D4 as illustrated in FIG. 7 is copied to the test image memory (processing SQ11).
The X coordinate of the test image data obtained is set to 0 and the Y coordinate is set to 0
The number of consecutive “0” (ejection data) is counted while incrementing by one from +1. If the count value is smaller than 64, all the previous “0” s are replaced with “1” (non-ejection data). The same operation is performed for the image width while increasing the X coordinate by +1. Next, the Y coordinate is set to 0, and X
The number of consecutive "0" s is counted while increasing the coordinates by one from +1. If the count value is smaller than 100, all the previous “0” s are replaced with “1”.
The same operation is performed for the image width while increasing the Y coordinate by one. As a result of this processing (SQ12), test image data in which continuous regions are extracted as described above can be created.

Next, in this example, this data is converted into image data of 50% duty which can be easily processed by the reading unit (processing SQ13), and as shown in FIG.
A continuous area is divided into four as test data for D1 ink, test data for D2 ink, test data for D3 ink, and test data for D4 ink, and written into the test image memory for each ink (process SQ14).

The reading means in this embodiment will be described with reference to FIG. In FIG. 9, X is the scanning direction of the print head, and Y is the direction of the ejection openings of the print head, which is the arrangement direction of 64 ejection openings. As a printing method, printing is performed using all ejection ports. In the present embodiment, 20 pixels are used as an area for reading the test image using the reading unit, and a warm-up area for printing is provided on the left side of the area.

The method for measuring the density unevenness in this embodiment will be described with reference to FIG. First, the entire density distribution is fetched, and a threshold value for distinguishing between a printed portion and a non-printed portion is determined in advance.Next, the value of the differentiated printed portion is determined. The average is obtained, and the average value x 0.9 is set as a new threshold,
If there is a value equal to or less than the threshold value, it is determined that density unevenness or non-ejection has occurred.

FIG. 11 is a flowchart showing the flow of the processing of this embodiment.

When the printing process is started, the ejection data stored in the image memory is sent to each print head in synchronization with the main scanning, and the ink is ejected.
When printing for one line is completed, the print medium moves by the number of ejection ports in the sub-scanning direction, and the next main scanning is performed.

In the procedure of this embodiment, before performing the main scanning, it is determined whether or not the data is stored in the test image memory to determine whether or not the area is for printing the test image (step S).
1) If the determination is affirmative, first, ejection data is sent from the test image memory for each ink, the test image is printed (step S3), and the test image is read and the density unevenness is measured. (Step S5).

Here, when it is determined that the density unevenness or the ejection failure has occurred according to the criteria described with reference to FIG. 10 (step S7), the recovery operation is performed without performing the sub-scan (paper feed) to the next line. Is performed (step S9).

Thereafter, if there is an area on the current line where a test image can be formed (steps S13 to S3), the test image is printed again, and reading and measurement are repeated. If there is no area for printing the test image, the data from the image memory is printed (step S15), the sub-scan is performed after the test image is painted out (step S17), and the process can be repeated. (Step S19 to Step S1). Note that the test image is formed by distributing data for an area that should be formed using the ink with the highest density to ink with a low density, and in each case, the test image is painted by printing the original data. Therefore, at least the deterioration of the image quality due to the printing of the test image does not occur.

As described above, when density unevenness or ejection failure occurs, the sub-scan is fed after the recovery processing, and the printing of data from the image memory is continued. Also, when it is determined that there is no density unevenness or ejection failure,
Sub-scanning is performed, and printing of data from the image memory is continued similarly.

On the other hand, during execution of the printing process as described above, the number of times density unevenness or ejection failure is detected and the number of times a recovery operation is performed are displayed on the display means (step S11). Can also be notified of the display content to the host computer connected to.

If density unevenness or ejection failure is detected during printing and no improvement is found by the recovery operation (step S9), it is often desired to re-form the image. Therefore, even after the determination of the end of printing (step S19), the processing of step S23 is skipped so that each image memory is not erased (step S21), and the contents are retained.

FIG. 12 shows the configuration of a control system of the present example for performing abnormal processing and operation.

The input data is distributed to the data for each ink by the distribution circuit 20, and is binarized by the binarization circuit 34, and the output image data composed of the binarized data for each ink is obtained. Image memory 21-1 to 21
-4. A region where a test image can be printed is extracted by the region separation circuit 35 from the image data in the image memory 21-4 for D4 ink, and stored in the test image memory 32. Further, the test image data for each ink is generated from the contents of the test image memory by the area separating circuit 35 and stored in the test image memories 33-1 to 3-4 for each ink.

A signal from the CCD 37 is read by a reading circuit 38.
Is performed, and the measurement result is sent to the main controller 14.

The main controller 14 controls the entire apparatus, including the control of each circuit and the ejection timing. As the main controller 14, usually, a CP
U, a one-chip microprocessor including a program storage ROM, a work RAM, and the like can be used. The main controller is a CCD controller 3
The light source 30 and the CCD 37 are controlled via 6.

Further, at the time of printing (at the time of ink ejection), the main controller 14 outputs the output image data from the image memories 21-1 to 21-4 or the image memory 3 for each ink.
While transferring test image data from 3-1 to 4-4,
The ejection operation of each print head 2 is controlled via the driver controller 18 and the print head driver 19, whereby an image is printed on the print medium 7. In addition, the drive of the carriage drive motor 8 is controlled via the motor driver 15, and the drive of the paper feed motor 17 is controlled via the motor driver 16.

As described above, even if density unevenness and ejection failure occur as a result of the print head used changing with time, the recovery operation of the print head can be executed at an appropriate timing (during an actual printing operation). it can. Furthermore, if density unevenness or ejection failure occurs even after the print head recovery operation is performed, the operator is notified of the condition appropriately to notify the operator of the condition, and the memory is printed until the print head recovers. Keep storing without erasing data. As a result, the ink jet printing apparatus can be used more easily by the user, and the method of this embodiment is effective.

In this example, four types of black (K) dark and light inks are used. However, even when other color inks are used or substituted, or when the types of dark and light inks are other than four, The effect can be expected. Or,
If one color (for example, black) is filled with another color (for example, yellow) and the image quality does not deteriorate, an area to be formed in black is extracted, and this is distributed to another color and tested. An image can also be formed.

(Second Example) The second embodiment of the present invention uses a configuration similar to that of the first example shown in FIGS. 1 and 2, and different points will be described below.

This embodiment is suitable for application to an ink jet printing apparatus used in the field of medical technology.
In the field of medical technology, a plurality of images sent from various medical / diagnostic devices via a network are arranged in a predetermined unit (for example, one print medium) as shown in FIG. Or, it is often desired to output in a form that is easy for the examinee to recognize.

Therefore, in this example, print image data to be sent to the print head is generated based on the input image in accordance with the sequence of image processing as shown in FIG.

For example, the input image data is an 8-bit digital value in which the brightest part of the captured image indicated by the input image data is "255" and the darkest part is "0". Then, in order to arrange a plurality of sent medical images on one output image, the image processing apparatus performs enlargement or reduction to an image size that is easily arranged, and performs processing for appropriately arranging the images (SQ21). At this time, for example, several types of predetermined arrangement examples are stored in the inkjet printing apparatus, and the layout can be determined according to a request from the host computer.

Next, multi-level error diffusion processing is performed on the arranged image data (SQ22). For example, the image data is converted to a 64
It is multi-valued to gradation. In this example, multi-level error diffusion of 64 gradations was performed.

Next, a distribution process (SQ23) is performed.
By using a pre-stored sorting table, image data for D1 ink, image data for D2 ink, image data for D3 ink, and image data for D4 ink are respectively generated.

Further, in this example, an area in which ink with the highest density is continuously printed is extracted according to the image processing sequence shown in FIG. 14 to create test image data.

For example, as shown in FIG. 15, if the border portion serving as the background of the group of images to be arranged is printed with the ink having the highest density, the printing is performed with the width in the sub-scanning direction when performing the arrangement processing. The ink is continuously ejected over the number of pixels larger than the number of ejection ports 64 of the head, and
A region where ink is continuously ejected over a width (100 pixels in this example) that can be read by the reading means in the main scanning direction is extracted and separated (SQ31). Then, the same image data conversion processing (SQ32) and division processing for each ink (SQ33) as in the first example are performed to create test image data.

FIG. 16 shows an example of the configuration of the printing apparatus control system of the present embodiment. The control system of the first embodiment (FIG. 12) differs from the control system of FIG. (SQ21-SQ23) enlargement / reduction / placement circuit 37, multi-level error diffusion circuit 38 and distribution circuit 39
Is different. Then, by performing the same processing as that shown in FIG. 11 and the like using this control system, the same effect as in the above-described first embodiment can also be obtained in this example.

(Others) The present invention can be applied not only to the above-described ink-jet printing apparatus but also to various apparatuses as long as a plurality of types of printing agents of different colors for the same color are used. Also, in addition to ink as a printing agent, thinner,
As long as the reflection density of an image formed by using a fixing agent, a surface treatment agent, and the like can be modulated, it is needless to say that the selection of the ink dye density alone is not limited to obtain an appropriate reflection density. It is.

As such an ink jet recording (printing) apparatus, there are an electromechanical conversion system and other various apparatuses. However, a means for generating thermal energy (for example, electrothermal conversion) is used as energy used for ink ejection. Body, laser light, etc.), and provides an excellent effect in a recording head and a recording apparatus of a type in which a change in the state of ink is caused by the thermal energy. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method is a so-called on-demand type,
Although it can be applied to any type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding nucleate boiling, heat energy is generated in the electrothermal transducer, and film boiling occurs on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal on a one-to-one basis.
This is effective because air bubbles inside can be formed. The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. 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 a 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. Further, if the conditions described in US Pat. No. 4,313,124 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 electrothermal converter (linear liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, U.S. Pat. No. 4,558,333 and U.S. Pat. No. 44,558 which disclose a configuration in which a heat acting portion is arranged in a bending region.
A configuration using the specification of Japanese Patent No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Application Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an aperture for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration is based on JP-A-59-138461, which discloses a configuration corresponding to a discharge unit. That is, according to the present invention, recording can be reliably 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 on which a recording apparatus can record. 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 integrally formed recording head.

In addition, even in the case of the serial type as described above, a recording head fixed to the apparatus main body, or an electric connection with the apparatus main body or ink from the apparatus main body by being mounted on the apparatus main body. 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 provided integrally with the recording head itself is used.

Further, it is preferable to add ejection recovery means for the recording head, preliminary auxiliary means, and the like as the configuration of the recording apparatus of the present invention since the effects of the present invention can be further stabilized. If these are specifically mentioned, the recording head is heated using capping means, cleaning means, pressurizing or suction means, an electrothermal transducer, another heating element or a combination thereof. Pre-heating means for performing the pre-heating and pre-discharging means for performing the discharging other than the recording can be used.

The number of colors of the inks to be mounted is, for example, different from those provided with different densities in correspondence with the single color inks, and also corresponds to at least some colors of a plurality of inks having different recording colors. A plurality of types having different densities (the number of types may be changed depending on colors) may be provided.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens or liquefies at room temperature may be used. In general, the ink jet method generally controls the temperature of the ink itself 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. Sometimes, the ink may be in a liquid state. In addition, in order to positively prevent temperature rise due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or to prevent evaporation of the ink, the ink is solidified in a standing state and heated. May be used. In any case, the application of heat energy causes the ink to be liquefied by the application of the heat energy according to the recording signal and the liquid ink to be ejected, or to start solidifying when it reaches the recording medium. The present invention is also applicable to a case where an ink having a property of liquefying for the first time is used. In such a case, the ink
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent Publication No. 1260, it is also possible to adopt a form in which the sheet is opposed to the electrothermal converter in a state where it is held as a liquid or solid substance in the concave portion or 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 to the above, the image forming system to which the ink jet recording apparatus of the present invention is applied includes not only an information processing apparatus such as a computer having an image output terminal, but also a copying apparatus combined with a reader, etc. A facsimile apparatus having a function may be used.

[0075]

As is apparent from the above description, according to the present invention, even if the print head to be used changes with time and, as a result, density unevenness or ejection failure occurs, the print head can be used at an appropriate timing. A recovery operation can be performed.

Further, if the density unevenness or the ejection failure occurs even after the print head recovery operation is performed, the operator is notified of such a condition as to appropriately notify the operator of the state, and the recovery is performed until the print head recovers. Since the print data in the memory is kept stored without being erased, it is possible to provide an ink jet printing apparatus which is easy for the user to use.

[Brief description of the drawings]

FIG. 1 is a processing block diagram best representing the features of a first embodiment of the present invention.

FIG. 2 is a schematic top view illustrating a configuration example of an inkjet printing apparatus according to a first example of an embodiment of the present invention.

FIG. 3 is a schematic perspective view showing a configuration of a print head and a reading unit in FIG.

FIG. 4 is a flowchart illustrating a sequence example of image processing according to the first embodiment of the present invention.

FIG. 5 is a diagram for explaining the concept of a data distribution table regarding which concentration of ink to use in the first embodiment of the present invention in which four types of inks having different densities are used for similar colors. .

FIG. 6 is a flowchart illustrating an example of a sequence of area extraction according to the first embodiment of the present invention.

FIG. 7 is an explanatory diagram of region extraction according to the first embodiment of the present invention.

FIG. 8 is an explanatory diagram of image division according to the first embodiment of the present invention.

FIG. 9 is an explanatory diagram for explaining an operation of a reading unit according to the first embodiment of the present invention.

FIG. 10 is an explanatory diagram for explaining a density unevenness determination criterion according to the first embodiment of the present invention.

FIG. 11 is a flowchart illustrating an example of a print processing procedure according to the first embodiment of the present invention.

FIG. 12 is a block diagram illustrating a configuration example of a control system according to the first embodiment of the present invention.

FIG. 13 is a flowchart illustrating a sequence example of image processing according to the second embodiment of the present invention.

FIG. 14 is a flowchart showing a sequence example of region extraction according to the second embodiment of the present invention.

FIG. 15 is an explanatory diagram of a formed image (medical image) according to the second embodiment of the present invention.

FIG. 16 is a block diagram illustrating a configuration example of a control system according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Carriage 2 Multi-nozzle print head 3 Ink tank 4 Conductor bundle 5 Guide rail 6 Belt 7 Print medium 8 Carriage drive motor 10 Recovery system 11 Ink supply pipe 12 Image memory 13 Recovery system controller 14 Main controller 15 Motor driver 16 Motor driver 17 Paper Feed motor 18 Driver controller 19 Print head driver 20 Distribution circuit 21-1 to 21-4 Image memory 22 Head scanning means 23 Transport means 24 Reading means 25 Density unevenness measuring means 26 Recovery means 27 Display means 28 Control means 29 Reading unit 30 Light source REFERENCE SIGNS LIST 31 lens 32 test image memory 33-1 to 4 test image memory for each ink 34 binarization circuit 35 area separation circuit 36 CCD controller 37 CCD 38 Reading circuit 39 Display panel

Claims (11)

[Claims] 1. A printing apparatus for forming an image using a plurality of printing means for applying printing agents having different color tones to a print medium, wherein the plurality of printing means are provided based on print data corresponding to the plurality of printing means. A driving unit for driving the printing unit, an area separating unit that separates an area continuously printed with a printing agent of a predetermined color tone from the print data, and a printing agent of the predetermined color tone included in the region. Means for driving the plurality of printing means by means of the drive means, wherein the print data portion for causing printing is divided so that printing is performed with the plurality of color printing agents; Reading means for reading the information on which the reading has been performed; and reading means for reading the information read by the reading means. Based on the taken data, printing device, characterized in that it comprises a determination means for determining the acceptability of the state of the plurality of printing means. 2. The printing apparatus according to claim 1, further comprising a recovery unit that performs a recovery operation for improving a printing agent application state of the printing unit based on the determination of the state by the determination unit. apparatus. 3. The printing apparatus according to claim 1, further comprising a notifying unit for notifying the state of the printing unit based on the judgment of the state by the judging unit. 4. A printing apparatus according to claim 1, wherein a plurality of said printing means are provided corresponding to printing agents having different densities for similar colors, and the printing agent having the predetermined color tone has the highest density. 3. The printing apparatus according to any one of 3. 5. Prior to printing the print data on the print medium, separation of the area, printing of the print data portion in a corresponding area on the print medium, reading, and the determination are performed. 5. The printing apparatus according to claim 4, further comprising means. 6. A storage unit for expanding the print data, a unit for erasing the stored contents after a printing operation is completed, and a unit for controlling the erasing operation based on a determination of the state of the printing unit. The printing apparatus according to any one of claims 1 to 5, further comprising: 7. When arranging a plurality of images on the print medium, means for forming a print pattern for judging whether the state of the printing means is good or not in an area of a background portion of the plurality of arranged images. The printing apparatus according to any one of claims 1 to 6, further comprising: 8. The printing apparatus according to claim 1, wherein the printing unit includes an ejection port for ejecting ink as a printing agent applied to the print medium, and a unit for generating energy used for ejecting the ink. The printing apparatus according to claim 1, wherein 9. The method according to claim 8, wherein the means for generating energy used for discharging the ink includes an electrothermal converter for generating thermal energy in response to energization.
A printing device according to claim 1. 10. The method according to claim 9, wherein the ink is ejected from the ejection port toward a print medium by utilizing film boiling generated in the ink by thermal energy applied from the electrothermal transducer. Printing equipment. 11. An image forming system, comprising: the printing apparatus according to claim 1; and means for supplying print data to the printing apparatus.