JP3015234B2 - Color inkjet recording method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color ink-jet recording method capable of recording a color image at a clear and high density, and more particularly, to a color ink using a color ink such as yellow, magenta or cyan and a black ink. The present invention relates to an inkjet recording method.

[0002] The present invention relates to paper, cloth, nonwoven fabric, and OHP.
The present invention can be applied to all devices using a recording medium such as paper, and specific devices include office equipment such as printers, copiers and facsimiles, and mass production equipment.

[0003]

2. Description of the Related Art Ink jet recording methods are used in printers, copier facsimile machines, and the like because of their low noise, low running cost, easy downsizing of their apparatuses, and easy colorization.

When an ink jet recording method is applied to a color recording apparatus, it is necessary to use "special paper" having an absorption layer in order to obtain a high-color image without bleeding of ink. In recent years, inks having improved printability on “plain paper” by improving ink have been put to practical use. However, at present, the print quality on “plain paper” is still at an insufficient level.
The biggest factors are the bleeding of the ink between the colors and the black recording quality (especially black character recording quality).
It is compatible.

[0005]

Generally, when a color image is obtained on plain paper by an ink jet recording method, a quick-drying ink having a high penetration rate into plain paper is used. For this reason, the color image portion becomes a high-quality image with no ink bleeding between colors, but the black image portion has a low density, and so-called feathering, in which ink bleeds along the paper fibers, occurs.

For example, in the case where a black image is present in the background of a color image portion, the above-mentioned problem of the black image portion is relatively inconspicuous and does not significantly lower the quality. If it exists independently of the image part, the quality will be degraded. Further, when the black image is a character, the character becomes indistinct because the image is unclear and lacks sharpness.

In order to obtain a high-quality image in which the density of the black image portion is high and feathering does not occur, it is necessary to eject ink having a relatively low penetration rate into plain paper to some extent. However, in this case, bleeding of the black ink and the color ink occurs at the adjacent boundary between the black image portion and the color image portion, and the quality is significantly deteriorated.

Although the problem relating to ink bleeding can be improved to some extent by the so-called fine mode in which an image is formed by dividing the image into a plurality of main scans, the problem of the black image quality has not been essentially solved. is the current situation.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art. When at least a black image portion exists independently of a color image portion, the density of the black image portion is reduced. Provided is a color ink jet recording method which is high in quality and does not cause feathering, and can obtain a clear image without ink bleeding at an adjacent boundary portion between a color image portion and a black image portion. The purpose is to:

[0010]

In order to achieve the above object, a color ink jet recording method according to the present invention comprises a yellow ink, a magenta ink, a cyan ink and a first black ink which have a relatively high penetration rate into a recording medium. It is determined whether or not a black image is adjacent to a color image by using ink and a second black ink whose penetration speed into a recording medium is relatively slower than that of the first black ink. And determining whether to form the black image with the first black ink or with the second black ink.

When the black image is adjacent to the color image, the black image mainly uses the first black ink, and when the black image is not adjacent to the color image, the black image is the second black ink. It is characterized in that only black ink is used.

When a black image is adjacent to a color image, the black image is formed by using the first black ink and at least one of yellow, magenta, and cyan inks in a predetermined ratio. It is characterized by.

Further, when the black image is adjacent to the color image, the black image is formed by using the first black ink and the second black ink at a predetermined ratio. .

[0014]

According to the above construction, even when different colors are adjacent to each other when forming a color image, color bleeding does not occur, and the second image used for forming a non-adjacent black image on a color image is formed.
With black ink, a high-quality image having high density and free from feathering can be obtained.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. First, the premise of each embodiment will be described.

FIG. 7 is an example showing an image in which a black image and a color image are mixed. The image portion A is composed of black enlarged characters of X, Y, and Z and an underline, and is bit image data. Image portion B is code data of black characters. An image portion C is an image having a black graph on a yellow background portion, and is bit image data. Image portion D is an image having black character code data on a cyan background portion.
The image portion E shows a case where a magenta image is present in a part of the background of the black bit image data.

According to the first aspect of the present invention, there is provided a method wherein
And a second black ink having a lower permeation speed than the first black ink is used to determine whether or not a color image exists adjacent to the black image. It is determined whether to form with black ink or mainly with the first black ink.

Accordingly, in the image shown in FIG. 7, the image portions C, D, and E are the target portions of the present invention. However, when the present invention is applied to an actual printer or the like, the present invention is applied to all the black image portions. Whether to apply the present invention or to apply the present invention only to, for example, code data of black characters may be determined as appropriate from the viewpoint of processing speed, cost image quality, and the like.

The ink used in the present invention, which has a high penetration rate into a recording medium, does not cause color bleeding even if different colors are adjacent to each other when forming a color image, and black ink which is not adjacent to the color image. With the second black ink used when forming an image, it is possible to obtain a high-quality image having a high density and free from feathering.

FIG. 1 is a perspective view of an ink jet printer to which the present invention can be applied.

The carriage 101 has recording heads 102a and 102b and a cartridge guide 103 mounted thereon, and can scan on a guide shaft 104 and a guide shaft 105.

The recording paper 106 is fed into the main body by a paper feed roller 107, is sandwiched by a paper feed roller 108 and a pinch roller (not shown), and is fed to the entire surface of the paper feed roller 108 by a paper pressing plate 109 to be printed. You. The ink cartridge is yellow, which has a high penetration rate into recording paper,
A color ink cartridge 110 containing four colors of magenta, cyan, and first black ink, and a black ink cartridge 111 containing second black ink are separately inserted into the cartridge 103, and are separately inserted into the recording head 102a and the recording head 102a. Communicates with 102b.

The yellow, magenta, cyan and second black inks contained in the color ink cartridge 110 have a high penetration rate into the recording paper, so that when forming a color image, the ink bleeds at the color boundaries. Does not occur. On the other hand, the second black ink accommodated in the black ink cartridge 111 has a high density of a black image and high quality with little ink bleeding.

The components of the ink used in this embodiment are as follows.

1. Yellow C.I. I. Direct Yellow 86 3 parts Diethylene glycol 10 parts Isopropyl alcohol 2 parts Urea 5 parts Acetylenol EH (Kawaken Chemical) 1 part Water balance

2. Magenta C. I Acid Red 289 3 parts Diethylene glycol 10 parts Isopropyl alcohol 2 parts Urea 5 parts Acetylenol EH (Kawaken Chemical) 1 part Water balance

3. Cyan C.I. I Direct Bull-199 3 parts Diethylene glycol 10 parts Isopropyl alcohol 2 parts Urea 5 parts Acetyleneol EH (Kawaken Chemical) 1 part Water balance

4. First black C.I. I Direct Black 154 3 parts Diethylene glycol 10 parts Isopropyl alcohol 2 parts Urea 5 parts Acetyleneol EH (Kawaken Chemical) 1 part Water balance

5. Second black C.I. I Direct Black 154 3 parts Diethylene glycol 10 parts Isopropyl alcohol 2 parts Urea 5 parts Water balance

As described above, cyan, magenta, yellow and the first black are different from the second black in the acetylenol E
By adding 1% of H, the permeability is improved. Other additives include other surfactants and alcohols.

Next, the recording heads 102a and 102b
Will be described in detail with reference to FIG.

FIG. 2A is a schematic perspective view of the recording head 102a, and ejection port groups for yellow, magenta, cyan, and black inks are arranged in a straight line on the front surface. Each group has 24 discharge ports for yellow, magenta, cyan, and black, and the interval between colors is equal to or greater than the nozzle pitch. In this embodiment, a space for eight nozzles is provided.

Each of these discharge ports is provided with an ink liquid path communicating with the discharge port, and a common liquid for supplying ink to these liquid paths is provided behind the portion where the ink liquid path is provided. A room is provided. An ink liquid path corresponding to each of the discharge ports is provided with an electrothermal converter that generates thermal energy used for discharging ink droplets from these discharge ports and an electrode wiring for supplying power thereto. ing. These electrothermal transducers and electrode wires are formed by a film forming technique on a 201 substrate made of silicon or the like. Further, the discharge port, the ink liquid path, and the common liquid chamber are formed by laminating a partition wall, a top plate, and the like made of resin or glass material on the substrate. Further behind, a drive circuit for driving the electrothermal transducer based on a recording signal is provided in the form of a printed circuit board.

Silicon substrate 201 and printed circuit board 202
The aluminum plate 203 is configured to be parallel to each other, and pipes 204 to 207 protrude from a plastic member 208 called a distributor extending in a direction perpendicular to the silicon substrate. These pipes communicate with a flow path, which communicates with a common liquid chamber.

There are four flow paths in the distributor, one for yellow, one for magenta, one for cyan, and one for black, which connect the respective common liquid chambers and pipes.

The ejection ports for yellow, magenta, cyan, and black provided in the recording head 102a
0 ng of ink is ejected.

On the other hand, FIG. 2B is a schematic view of the recording head 102b, and the same members as those of the recording head 102a are denoted by the same reference numerals as in FIG. 2A. Recording head 1
The second black ink ejection port 128 is provided on the front surface of the second 02b.
Each of the discharge ports is provided with an ink liquid path communicating with the discharge port, similarly to the recording head 102a. Is provided with a common liquid chamber.
Since the recording head 102b discharges only the second black ink, only one pipe protrudes from the distributor 208.

Approximately 80 ng of ink is ejected from a black ejection port provided in the recording head 102b.

In this ink jet printer, a recording head for forming a color image and a recording head for forming a high-quality black image are separately provided.
In particular, when printing only a black image, or when an image in which a black image and a color image are mixed, the black image is continuous in the recording paper feed direction as shown in image portions A and B in FIG. High-speed printing can be performed using all 128 nozzles of the head 102b.

FIG. 3 is an electric control block diagram of the color ink jet printer described above.

Reference numeral 301 denotes a system controller for controlling the entire apparatus, and a storage element (RO) containing a microprocessor and a control program therein.
M), a storage element (RAM) used when the microprocessor performs processing, and the like are arranged. 302, a driver for driving the print head in the main scanning direction;
Similarly, reference numeral 303 denotes a driver for moving in the sub-scanning direction. Reference numerals 304 and 305 denote motors corresponding to the driver, which operate by receiving information such as speed and moving distance from the driver.

Reference numeral 306 denotes a host computer, which transfers information to be printed to the printing apparatus of the present invention. Reference numeral 307 denotes a reception buffer for temporarily storing data from the host computer 306, and accumulates data until data is read from the system controller 301. A frame memory 308 expands data to be printed into image data, and has a memory size necessary for printing. In this embodiment, a frame memory capable of storing one print sheet will be described, but the present invention is not limited to the size of the frame memory.

Reference numeral 309 denotes a storage element for temporarily storing data to be printed, and the storage capacity varies depending on the number of nozzles of the print head. Reference numeral 310 denotes a print control unit for appropriately controlling the print head according to a command from the system controller, and for controlling the ejection speed, the number of print data, and the like. Reference numeral 311 denotes a nozzle (head) 312Y for discharging yellow ink, a nozzle (head) 312M for discharging magenta ink, and a nozzle (head) 312 for discharging cyan ink.
C, a driver for driving a nozzle (head) 312Bk for discharging the first black ink and a nozzle (head) 313 for discharging the second black ink. Is controlled by this signal.

(Embodiment 1) FIG. 4 is an operation flow in Embodiment 1 of the present invention.

STEP 1 is the first step in which data is transferred from the host computer 306 in FIG. 3 and the data stored in the reception buffer 307 is processed by the system controller 301, and the stored data is read out. . In STEP 2, it is determined whether the read data includes black data or data other than black data. If black data is included, go to STEP3; otherwise, go to STEP7.

In STEP 3, it is determined whether the target black image recording area is character code data or bit image data.
If the image data is bit image data, the process proceeds to STEP5.
At STEP 4, attention is paid to the black data, and it is determined whether or not there is color recording data at a pixel adjacent to the periphery of the black image recording area. If a color image exists at a position adjacent to the black image, the process proceeds to STEP5; otherwise, the process proceeds to STEP6.

In STEP 5, black image information which is character code data and a color image is present at an adjacent position and black image information which is bit image data are first data.
In the black ink recording buffer 309Bk1. In STEP 6, the black image information is developed in the second black ink recording buffer 309Bk2.

In STEP 7, the color data of each of the Y, M, and C colors that have not been expanded are stored in the buffer 309 for each color.
Y, 309M, and 309C.

In STEP 8, data is read from the reception buffer, and it is determined whether or not there is data to be printed and whether or not data of one page has been received. As a result of the determination, if there is no print data, or if there is print data but one page of data has already been received, STEP 9
Proceed to. In other cases, the process returns to STEP1. In STEP 9, the printing operation is performed by the recording head 102.

FIG. 5 shows a process of forming a color image including a black image as shown in FIG. 5 (f) in accordance with the operation flow of the printing apparatus described above. FIG. 5 (f)
Is composed of a black character "K" from the left side in the figure, a black character "B" in a yellow background, a magenta character "M", and a cyan character "C". These characters are character code characters.

First, as shown in FIG. 5A, black characters are printed using the recording head 102a and the recording head 102b. At this time, the black character "K" is printed by the recording head 102b because it is not adjacent to the color image, and the black character "B" is printed by the recording head 102a because the yellow image exists on the background. After the upper half of each black character is printed, the recording paper is fed for 24 nozzles.

Subsequently, as shown in FIG. 5B, the lower half of each black character is printed, and printing of the black character ends at this stage. At the same time, the cyan character "C"
Is printed by the recording head 102a.

Further, the recording paper is fed by 24 nozzles, and FIG.
As shown in (c), a part of the cyan character "C" and a part of the magenta character "M" are printed.

Further, the recording paper is fed by 24 nozzles, and FIG.
As shown in (d), the remaining portion of the cyan character "C" and a portion of the magenta character "M" are printed.

Further, the recording paper is fed by 24 nozzles, and FIG.
As shown in (e), the remaining half of the magenta character "M" and the upper half of the yellow image in the background of the black character "B" are printed.

Further, the recording paper is fed by 24 nozzles, and FIG.
As shown in (f), the lower half of the yellow image is printed,
All image formation ends.

The resulting image is particularly black
K "is high density, no feathering, and black letter" B "
Was of high quality with no ink bleeding at the boundary with the background yellow image.

As described above, in this embodiment, it is determined whether or not a black character of a character code is adjacent to a color image, and if so, a black character is printed with the color image in order to print the black character with the recording head 102a. A clear image with no ink bleeding at the boundary, while a non-adjacent black character can be printed by the recording head 102b, so that an image with high quality black characters can be obtained.

(Embodiment 2) Embodiment 2 is an improvement of Embodiment 1, in which the quality of black characters adjacent to a color image is improved.

That is, when printing black characters adjacent to a color image, the second black ink from the recording head 102b is used in addition to the first black ink from the recording head 102a.

FIG. 6 shows the method of driving at that time. Pixels painted out in black have the recording head 102b.
The second black ink is applied to the three pixels hatched by the recording head 102a.
The black ink. The second black ink has a low penetration rate into the recording paper and has a large ejection amount of 80 ng.
When the black ink is mixed with the black ink at an appropriate ratio, the density increases and the quality is improved.

In the present embodiment, the second black ink is ejected at a rate of one pixel per four pixels. However, if the rate at which the second black ink is ejected is increased, the quality of black characters is improved, but bleeding with a color image is gradually performed. , And the overall quality tends to decrease, so it is necessary to determine the quality in consideration of the characteristics of the ink used, the driving conditions, and the like.

(Embodiment 3) FIG. 8 is a schematic view of another color ink jet printer to which the present invention can be applied. 1y is a recording head for yellow ink, 1m is a recording head for magenta ink, and 1c is a recording head for magenta ink. The recording head for cyan ink, 1b is the first recording head for black ink, and 1k is the second recording head for black ink.
Black ink recording head, 2 is a carriage on which the recording head is mounted, 3 is a flexible cable for sending an electric signal from the printer body to the recording head, 4 is a cap unit having recovery means, 5y, 5m, 5c, 5b, 5k
Is a cap member corresponding to the recording heads 1y, 1m, 1c, 1b, and 1k, and 6 is a wiper blade made of a member such as rubber.

The configuration of the nozzles of the print heads 1y, 1m, 1c and 1b is basically the same as that of the print head 102b shown in the first embodiment, and each head has 128 discharge ports. The difference from the first embodiment is that about 40 ng of ink is ejected from each nozzle. For these recording heads, the ink used in the recording head 102a of the first embodiment and having a high penetration rate into the recording paper is used. The recording head 1k has the same structure as the recording head 102b of the first embodiment.
It has eight nozzles and ejects about 80 ng of ink. This recording head includes the recording head 102b of the first embodiment.
The same ink as that used for the above is used.

The electric control in the present embodiment is almost the same as that in the first embodiment, and the description is omitted.

FIG. 9 shows a basic operation flow of this embodiment. The difference from the first embodiment is that the determination as to whether the black image and the color image are adjacent or not is performed not only for the character code but also for the bit image data.
Therefore, the operation flow of FIG. 9 does not include a step of determining whether or not the black data is a character code in STEP 3 in the operation flow of FIG.

The feature of this embodiment is that the recording time is short because the recording heads of the same size are arranged in parallel. Further, since it is determined whether or not all the black images are adjacent to the color image, the second black ink is used also for the black bit image data that is not adjacent to the color image, and a high-quality image can be obtained.

(Embodiment 4) FIG. 10 schematically shows the structure of a recording head used in this embodiment. The recording head 21 and the recording head 22 eject two different colors of ink, respectively, which have a high penetration rate into the recording paper. That is, the recording head 21 ejects yellow ink and cyan ink, and the recording head 22 ejects magenta ink and first black ink. There are 32 ejection openings for ejecting ink of each color, and 8
A space for the nozzle is provided. In addition, each discharge port is configured to discharge about 40 ng of ink.

The recording head 23 is for discharging the second black ink, and has 64 discharge ports, and is configured to discharge about 80 ng of ink from each discharge port.

FIG. 11 is a diagram for explaining a process of forming a color image using the recording head having the configuration shown in FIG.

First, as shown in FIG. 11A, the upper half of the black character "K" is printed using the recording head 23 and the upper half of the black character "B" is printed using the recording head 22. Printing and printing of the upper half of the cyan character “C” using the recording head 21 are performed.

After the recording paper has been fed by 32 nozzles, FIG.
As shown in (b), the lower half of the black character "K" is printed using the recording head 23, the lower half of the black character "B" is printed using the recording head 22, and the recording head 21 is printed. Then, printing of the lower half of the cyan character "C" is performed, and printing of the black character and the cyan character is completed. At this time, a part of the magenta character "M" is printed by the recording head 22 and a part of the yellow image of the background part of the black character "B" is printed by the recording head 21.

Subsequently, after the recording paper has been fed by 32 nozzles, as shown in FIG. 11C, the recording head 22 prints a part of the magenta character "M" and the recording head 21 prints one yellow image. The print of the copy is performed.

Thereafter, the image formation is similarly performed as shown in FIG. 11D, and the image formation is completed.

In this embodiment, as in the third embodiment, a method of determining whether or not all black images are adjacent to a color image can be used to obtain a high-quality color image.

The present invention has been described with reference to the embodiments.
The present invention is not limited to these. For example, in a black image adjacent to a color image, not only the first black ink or the first black ink and the second black ink are mixed, but also the first black ink and the color ink are mixed at an appropriate ratio. Is also good. Further, the recording head does not need to be divided into a plurality of recording heads, and may be configured to be able to discharge five types of ink from one recording head.

In each of the above-described embodiments, the determination of the image
A case has been described in which control / processing means such as determination processing, image expansion processing / replacement processing, etc. are all controlled by the control unit in the recording apparatus based on data received from the host computer. It is not limited.

For example, it is also possible to extend all of the control and processing means to a system in which the external device is executed by a printer driver or the like and the actual recording data after the pixel replacement processing is completed. In many cases, the external device connected to the recording device is a host computer,
The host computer has better processing power and RAM capacity for performing the above processing.

The image determination processing may be performed by the host computer, and the image development processing may be performed by the printer.

Although the embodiment has been described using a so-called bubble jet recording method in which bubbles are generated in ink by an electrothermal transducer and ink is caused to fly by the action of the bubbles, the ink is converted by an electromechanical transducer. It is needless to say that the present invention can also be applied to a so-called piezo-type ink jet recording system in which the image is caused to fly.

The present invention particularly provides an excellent effect in a recording apparatus using an ink jet type recording head for performing recording by forming a flying liquid by utilizing thermal energy among ink jet recording methods.

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 recording information and giving 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 the drive signal
This is effective because air bubbles in the interior 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 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.

The configuration of the recording head includes a combination of a discharge port, a liquid path, and an electrothermal converter (a linear liquid flow path or a right-angled liquid flow path) as disclosed in the above-mentioned respective specifications. U.S. Pat. No. 4,558,333 and U.S. Pat.
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, the recording head fixed to the apparatus main body or the electric connection with the apparatus main body or the ink from the apparatus main body is attached to the apparatus main body by being attached to 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.

Further, as for the type and number of the recording heads to be mounted, two or more recording heads may be provided corresponding to a plurality of inks having different recording colors and densities. That is, for example, the printing mode of the printing apparatus is not limited to a printing mode of only a mainstream color such as black, but may be any of integrally forming a printing head or a combination of a plurality of printing heads. The present invention is also very effective for an apparatus provided with at least one of the recording modes of full color by color mixture.

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.

Further, the form of the ink jet recording apparatus of the present invention is not limited to those used as image output terminals of information processing equipment such as computers, copying apparatuses combined with readers and the like, and facsimile apparatuses having a transmission / reception function. It may take a form.

[0090]

As described above, according to the present invention, the bleeding of the black ink and the other color inks (yellow, magenta, cyan) can be reduced while maintaining the character quality.

[Brief description of the drawings]

FIG. 1 is a perspective view of an inkjet recording apparatus to which the present invention can be applied.

FIG. 2 is a head mechanism diagram of an ink jet recording apparatus to which the present invention can be applied.

FIG. 3 is a control circuit block diagram of an ink jet recording apparatus to which the present invention can be applied.

FIG. 4 is an operation flow of the first embodiment.

FIG. 5 is a diagram illustrating an image forming process according to the first embodiment.

FIG. 6 is a diagram illustrating a driving pattern for forming a black image according to the second embodiment.

FIG. 7 is a diagram showing an example of an image for explaining the present invention.

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

FIG. 9 is an operation flow of the third embodiment.

FIG. 10 is a diagram illustrating a configuration of a recording head used in a fourth embodiment.

FIG. 11 is a diagram illustrating an image forming process according to a fourth embodiment.

[Explanation of symbols]

Reference Signs List 101 carriage 102 print head 103 cartridge 106 recording paper 110 color ink cartridge 111 black ink cartridge 301 system controller 306 host computer 307 reception buffer 308Y, 308M, 308C, 308Bk Frame memory of each color 309Y, 309M, 309C, 309Bk1, 309
Bk2 Data buffer for each color 310 Print control unit 311 Print driver 312Y, 312M, 312C, 312Bk, 313
Print head of each color

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Nao Yaegashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-5-276373 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) B41J 2/21

Claims (5)

(57) [Claims] 1. A recording medium comprising: a yellow ink, a magenta ink, a cyan ink, and a first black ink, each having a relatively high permeation speed into a recording medium; A color ink jet recording method for performing recording using a second black ink which is relatively slow, comprising: a step of determining whether or not a black image is adjacent to a color image; and Deciding whether to form a black image with the first black ink or with the second black ink. 2. The method according to claim 1, wherein the determining step includes: when the black image is adjacent to the color image, forming the black image mainly with the first black ink; and when the black image is not adjacent to the color image, 2. The color ink jet recording method according to claim 1, wherein a decision is made to form a black image only with the second black ink. 3. The method according to claim 1, wherein when the black image is adjacent to the color image, the black image uses the first black ink and at least one of yellow, magenta, and cyan inks in a predetermined ratio. 3. The color ink jet recording method according to claim 2, wherein the forming is determined. 4. The method according to claim 1, wherein when the black image is adjacent to the color image, the black image is formed by using the first black ink and the second black ink at a predetermined ratio. 3. The color inkjet recording method according to claim 2, wherein: 5. The color inkjet recording method according to claim 1, wherein each of the inks is ejected by thermal energy.