JPH08216389A - Ink jet printing device, ink jet printing method and printed matter - Google Patents

Abstract

PURPOSE: To reduce the deterioration of an image due to the blurring of ink at the boundary between a black image and a color image and obtain a high quality image with the amount as necessary and small as possible of a printability improving liquid by a method wherein the discharge region of the printability improving liquid discharging to adjacent boundary region is changed. CONSTITUTION: A printing controlling section 310 controls printing speed, the number of printing data and the like of the heads by means of the command sent from a system controller. The printing controller section also produces the data for discharging printability improving liquid. The system controller 301 and the printing controlling section 310 function as the liquid discharging head controlling means of the printability improving liquid. A recording head 312s for discharging the printability improving liquid and a driver 311 for driving a head 312k for discharging ink are controlled by the signal sent from the printing controlling section 310.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printing apparatus capable of printing a high quality image on a print medium, an ink jet printing method and a printed matter thereof, and more specifically, for improving printability by ink. The present invention relates to an inkjet printing technique for ejecting a liquid that insolubilizes or agglomerates a dye or pigment in ink onto a print medium. INDUSTRIAL APPLICABILITY The present invention can be applied to all devices that use print media such as paper, woven fabric, non-woven fabric, textile products, OHP paper, leather, metal, and synthetic resin. Specific applicable devices include office work such as printers, copiers, and facsimiles. Examples include equipment and industrial mass production equipment.

[0002]

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

Generally, the color ink jet recording method is a method of performing color recording by using three color inks of cyan, magenta and yellow, or four color inks with black added. By the way, when the inkjet recording method is applied to a color recording apparatus, in order to obtain a color image with high colorability without ink bleeding, it is necessary to use a special paper that has been treated to prevent bleeding. .
However, in recent years, those having printability on plain paper have been put into practical use by improving the ink. However, the current printing quality is still at an insufficient level.

The most important factor is the quality of a black image recorded in a color image. Normally, when a color image is formed on plain paper by the ink jet recording method, a quick-drying ink that has a high penetration speed into the plain paper is used, and therefore the color image area is a high-quality image with little ink bleeding between colors. Becomes However, the black image portion has a low density, and a phenomenon called so-called feathering occurs in which ink bleeds along the fibers of the paper.
For example, when there is a black image in the background of the color image part, the black image part is low in density and relatively inconspicuous even if feathering occurs, but the black image part is independent of the color image part. If it exists, there is a problem that the deterioration of quality is obvious. In particular, when the black image is a character, it becomes an unclear character lacking sharpness, so that the quality thereof is extremely deteriorated. 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 a large amount of ink having a relatively slow penetration speed into plain paper. However, in this case, bleeding of the black ink and the color ink occurs at the adjacent boundary portion between the black image portion and the color image portion, and the quality is significantly impaired.

[0005]

As described above, prevention of ink bleeding between black and color inks and enhancement of the density of a black image,
Prevention of feathering has been a conflicting issue. Therefore, Japanese Patent Laid-Open No. 3-146355 proposes a method of not recording an area along the boundary area between black and color. However, this method has a problem that recorded data changes. In addition, JP-A-4-1580
In Japanese Patent Publication No. 49, a method is proposed in which a multi-color head for color recording and a head for character recording are provided, and recording is performed by switching between the multi-color head and the character recording head based on a recorded image. However, in this method, in addition to the conventional multi-color head for color recording, a head for character recording is provided, so that cost increase and device enlargement are inevitable. Further, when a black image recorded by the color recording head and a black image recorded by the character recording head are mixed, an unpleasant sensation occurs due to the difference in quality between the two.

At present, there has been considered a method of forming a black area along the boundary area between black and color by overlapping color inks to prevent bleeding at the boundary area between black and color. In principle, black can also be obtained by mixing (mixing) three colors of Y, M, and C, but a black image formed by mixing color inks in this way is Poor color development.

On the other hand, JP-A-56-84992 and JP-A-64-63185 disclose a technique using a liquid which insolubilizes the dye in the ink. JP 5
Japanese Patent Laid-Open No. 6-84992 discloses a method of coating a recording paper with a material for fixing a dye in advance. However, in this method, it is necessary to use a specific recording paper, and in order to apply the material for fixing the dye in advance, it is unavoidable that the apparatus becomes large in size and cost is increased, and furthermore, it is stable on the recording paper. There is a problem that it is difficult to apply the material with a predetermined film thickness.

Further, in JP-A-64-63185,
A technique is disclosed in which a colorless ink that insolubilizes a dye is attached onto a recording paper by an inkjet recording head. According to this method, since the dot diameter of the colorless ink is made larger than the dot diameter of the image ink, the desired characteristics are satisfied even when the stepped positions of the image ink and the colorless ink are deviated. I am going to do it. In this method, since the amount of colorless ink ejected onto the portion corresponding to the image position is larger than usual, there is a problem that not only the ink drying time becomes longer but also an unclear image may result.
Also, when using such colorless ink,
In order to prevent the ink drying time from becoming long, it is necessary to use a colorless ink that has a relatively high permeation rate into the recording material. There are problems such as lack of sharpness.

Therefore, the present invention has improved the above-mentioned problems of the prior art. Even in the case of an image in which a black image and a color image are mixed, the density is high and a black image in which feathering does not occur, and a black image and a color image are not generated. An object of the present invention is to provide an inkjet printing apparatus, an inkjet printing method, and a printed matter that can obtain a high-quality image with less ink bleeding between images.

[0010]

SUMMARY OF THE INVENTION The present invention which solves the above-mentioned problems is directed to an ink ejection head for ejecting a black ink and a plurality of color inks other than black, and a black formed on the print medium by the black ink. A liquid ejection head for ejecting a printability improving liquid for improving printability in inkjet printing to at least a part of a boundary portion where the image region and the color image region formed by the color ink other than black are adjacent to each other. The time from when one of the black image area and the color image area is formed to when the other image area is formed via the boundary portion is printed on the print medium by using the color ink type. In another inkjet printing apparatus, the boundary portion is formed after one of the black image area and the color image area is formed. When the color image area is formed using color ink having a relatively short time until the other image area is formed via the color image area, the color image area is formed using color ink having a relatively long time. An ink jet printing apparatus comprising a liquid ejection head control means for increasing the amount of the printability improving liquid ejected onto at least a part of the boundary portion as compared with the case of forming.

According to the present invention, a black ink, a plurality of color inks other than black, a black image area formed by the black ink and a color image area formed by the color ink other than black on a print medium. Is printed on a print medium using a printability improving liquid applied to improve the printability in inkjet printing on at least a part of the adjacent boundary portion, and one of the black image area and the color image area is An ink jet printing method in which the time from the formation to the formation of the other image area through the boundary is different depending on the type of the color ink, and one of the black image area and the color image area is formed. The time from when the image is formed to when the other image area is formed through the boundary is relatively short. Serial color - when forming the image area, the use of relatively long color ink the time color -
There is provided an inkjet printing method characterized by increasing the amount of the printability improving liquid discharged onto at least a part of the boundary portion as compared with the case of forming an image region.

According to the present invention, a print printed on a print medium using a black ink, a plurality of color inks other than black, and a printability improving liquid applied to improve printability in ink jet printing. Of the printability improving liquid, wherein a black image area formed of black ink on a print medium and a color image area formed of the color ink other than black are present in at least a part of a boundary portion adjacent to each other. The component amount per unit area is different from the component amount per unit area of the printability improving liquid present in at least a part of the boundary portion where the black image region and the color image region formed by another color ink are adjacent to each other. A printed matter characterized by the above is provided.

[0013]

According to the above-described structure, the minimum necessary printing is performed by changing the ejection area of the printability improving liquid ejected to the adjacent boundary area in consideration of the time difference until the black image and each color image are adjacent to each other. With the property-improving liquid amount, deterioration of the image due to ink bleeding at the boundary between the black image and the color image can be reduced, and a high-quality image can be formed.

[0014]

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

(Embodiment 1) FIG. 1 is a schematic view of an ink jet printer to which the present invention can be applied, in which a head 1s for ejecting a printability improving liquid, yellow, magenta, cyan and black. A head 1k for ejecting each color ink, a carriage 2 carrying the head,
A flexible cable 3 for sending an electric signal from the printer body to each head, a cap unit 4 having recovery means, a cap member 5s corresponding to the head 1s, a cap member 5k corresponding to the head 1k, and a wiper made of rubber or the like. It has a blade 6, a feeding tray 8 for feeding the print medium 7, and the like. In the printer having such a configuration, the head 1s and the head 1k are serially scanned in a direction (main scanning direction) B orthogonal to the print medium conveyance direction A to perform printing with a width corresponding to the number of nozzles. During printing, the print medium is intermittently conveyed with a feed amount equal to the print width. Further, the printer according to the present embodiment is configured to eject the ink for forming an image after ejecting the printability improving liquid.

FIG. 2 is a schematic view of the nozzles of the heads 1s and 1k when viewed from the ink ejection surface side to show the structure of the nozzles. The head 1s is provided with 160 nozzles 11s for ejecting the printability improving liquid in the vertical direction. Similarly, the head 1k is provided with 24 nozzles 11y for ejecting yellow ink, 24 nozzles 11m for ejecting magenta ink, 24 nozzles 11c for ejecting cyan ink, and black ink. 64 nozzles 11k for discharging are provided, and a space for 8 nozzles is provided between the nozzles of each color. Furthermore, from the nozzle 11s, about 40 ng per drop
Printability improving liquid of the nozzle 11y, the nozzle 11m,
About 40 ng of each color ink is ejected from the nozzle 11c, and about 80 ng of black ink is ejected from the nozzle 11k.

The composition of the ink and the printability improving liquid used above is as follows, for example. (Ink composition example) Yellow diethylene glycol 10 parts by weight Isopropyl alcohol 2 parts by weight Urea 5 parts by weight Acetylenol EH 1 part by weight C.I. I. Direct Yellow 86 2.5 parts by weight Water balance 2. Magenta diethylene glycol 10 parts by weight Isopropyl alcohol 2 parts by weight Urea 5 parts by weight Acetylenol EH 1 part by weight C.I. I. Acid Red 289 3.5 parts by weight Water balance 3. Cyanidiethylene glycol 10 parts by weight Isopropyl alcohol 2 parts by weight Urea 5 parts by weight Acetylenol EH 1 part by weight C.I. I. Direct Blue 199 3.5 parts by weight Water balance 4. Black Thiodiglycol 5 parts by weight Glycerin 5 parts by weight Isopropyl alcohol 4 parts by weight Urea 5 parts by weight Food Black 2 3 parts by weight Water balance (printability improving liquid) Polyallylamine-hydrochloride 1 part by weight Benzalkonium chloride 1 part by weight Thio Diglycol 10 parts by weight Acetylenol EH 0.5 parts by weight Water remaining part

With the above composition, ink bleeding between color print areas is reduced by using an ink having a relatively high penetration speed into the print medium as the color ink, and penetrating into the print medium as the black ink. By using an ink having a relatively low speed, it is possible to obtain a high-density black image in which feathering hardly occurs.
Therefore, when the black image and the color image are adjacent to each other, ink bleeding is likely to occur.

In the above-described mixing of the printability improving liquid and the ink, in the present invention, as a result of mixing the printability improving liquid and the ink on the print medium or at the position where the ink has penetrated, the first step of the reaction. Among the cationic substances contained in the printability-improving liquid, a low molecular weight component or a cationic oligomer and a water-soluble dye having an anionic group used in the ink or an anion used in the pigment ink. The ionic compound causes an association due to ionic interaction, and instantaneously causes separation from the solution phase. As a result, dispersion destruction occurs in the pigment ink, and pigment aggregates are formed.

Next, as the second step of the reaction, the above-mentioned dye and a low molecular weight cationic substance or cationic oligomer are used.
The aggregate of the pigment or the aggregate of the pigment is adsorbed by the polymer component contained in the printability improving liquid, so that the size of the aggregate of the dye or the aggregate of the pigment generated by the association is further increased, and the print medium. It becomes difficult to enter into the gap between the fibers, and as a result, only the liquid portion that has undergone solid-liquid separation penetrates into the print medium, so that both print quality and fixability are achieved. At the same time, the agglomerates or pigment agglomerates formed by the low molecular weight component of the cationic substance or the cationic oligomer, the anionic dye and the cationic substance produced by the mechanism as described above have a high viscosity, and the movement of the solvent body Since they do not move together with each other, even if adjacent ink dots are formed of different color inks as in full-color image formation, they do not mix with each other and bleeding does not occur. In addition, the above-mentioned aggregate is essentially insoluble in water, and the water resistance of the formed image is perfect. Further, it also has the effect of improving the light fastness of an image formed by the shielding effect of the polymer.

In the present specification, the effect of improving the printability of the printability-improving liquid can be achieved only by the first step, and preferably both of the first step and the second step. Achieved by The printability is improved by improving image quality such as density, saturation, sharpness of edge portion, dot diameter and the like, ink fixability, weather resistance such as water resistance and light resistance, that is, image storability. At least one of the things is obtained.

Further, in carrying out the present invention, it is not necessary to use a cationic polymer substance having a large molecular weight or a polyvalent metal salt as in the prior art, or the effect of the present invention is obtained even if it is necessary. Since it is only necessary to use it as an auxiliary in order to further improve, the usage amount can be minimized. As a result, the deterioration of the color developability of the dye, which is a problem when trying to obtain the water resistance effect by using the conventional cationic polymer substance or polyvalent metal salt, is eliminated.

The print medium used to carry out the present invention is not particularly limited.
Conventionally used so-called plain paper such as copy paper and bond paper can be preferably used. Of course, specially made coat paper and OH for inkjet printing
A transparent film for P can also be suitably used, and general high-quality paper or glossy paper can also be suitably used.

Further, the ink jet printing apparatus of the present invention is not only for office equipment such as printers, copiers and facsimile machines, but also for large-scale systems such as decorative printers and computer design printing systems for directly printing patterns on cloth. It can also be used as a mass production device such as a printing device.

As the color material of each ink, for example, a pigment-containing material or a mixture of a dye and a pigment may be used.

The following can be mentioned as an example of the pigment ink which causes aggregation when mixed with the above-mentioned printability improving liquid. That is, as described below,
Yellow, magenta, cyan, and black color inks, each containing a pigment and an anionic compound, Y2, M2, C2
And K2 can be obtained.

Black ink K2 anionic polymer P-1 (styrene-methacrylic acid-ethyl acrylate, acid value 400, weight average molecular weight 6,0)
00, an aqueous solution with a solid content of 20%, a neutralizing agent: potassium hydroxide) was used as a dispersant, and the following materials were placed in a batch type vertical sand mill (made by AIMEX Co., Ltd.) and 1 mm diameter glass beads were filled as a medium. Then, while cooling with water, 3
Time-dispersed processing was performed. Viscosity after dispersion is 9 cps, pH
Was 10.0. This dispersion was centrifuged to remove coarse particles, to prepare a carbon black dispersion having a weight average particle diameter of 100 nm. (Composition of carbon black dispersion) -P-1 aqueous solution (solid content 20%) 40 parts-Carbon black Mogul L (manufactured by Cablack Co.) 24 parts-Glycerin 15 parts-Ethylene glycol monobutyl ether 0 .5 parts-Isopropyl alcohol 3 parts-Water 135 parts

Next, the dispersion obtained above was sufficiently dispersed to obtain a black ink K2 for ink jet containing a pigment. The solid content of the final preparation was about 10%.

Yellow-ink Y2 anionic polymer P-2 (styrene-acrylic acid-methyl methacrylate, acid value 280, weight average molecular weight 1
1,000, an aqueous solution with a solid content of 20%, a neutralizing agent: diethanolamine) was used as a dispersant, and the following materials were used to carry out a dispersion treatment in the same manner as in the preparation of the black ink K2. A yellow color dispersion having a particle size of 103 nm was prepared. (Composition of yellow-color dispersion) P-2 aqueous solution (solid content 20%) 35 parts C.I. I. Pigment Yellow 180 24 parts (Novapa Muier PH-G, manufactured by Hoechst) -Triethylene glycol 10 parts-Diethylene glycol 10 parts-Ethylene glycol monobutyl ether 1.0 part-Isopropyl alcohol 0 .5 parts ・ Water 135 parts

Next, the yellow color dispersion thus obtained was sufficiently diffused to obtain a yellow ink Y2 for ink jet containing a pigment. The final product has a solid content of about 1
It was 0%.

Using the anionic polymer P-1 used in the preparation of the cyan ink C2 and the black ink K2 as the dispersant, and using the materials shown below, the same as in the case of the carbon black dispersion described above. Dispersion treatment was performed to prepare a cyan color dispersion having a weight average particle diameter of 120 nm. (Composition of cyan color dispersion) P-1 aqueous solution (solid content 20%) 30 parts C.I. I. Pigment Bull-15: 3 24 parts (Fast Gemble-FGF, manufactured by Dainippon Ink & Chemicals, Inc.)-Glycerin 15 parts-Diethylene glycol monobutyl ether 0.5 parts-Isopropyl alcohol 3 parts-Water 135 parts

Next, the cyan color dispersion obtained above was sufficiently diffused to obtain a cyan ink C2 for ink jet containing a pigment. The final product has a solids content of about 9.6.
%Met.

Using the anionic polymer P-1 used in the preparation of the magenta ink M2 black ink K2 as a dispersant and using the materials shown below, the same as in the case of the carbon black dispersion described above is used. Dispersion treatment was performed to prepare a magenta color dispersion having a weight average particle diameter of 115 nm. (Composition of magenta color dispersion) P-1 aqueous solution (solid content 20%) 20 parts C.I. I. Pigment Red 122 (manufactured by Dainippon Ink & Chemicals, Inc.) 24 parts ・ Glycerin 15 parts ・ Isopropyl alcohol 3 parts ・ Water 135 parts

Next, the magenta color dispersion obtained above was sufficiently diffused to obtain a magenta ink M2 for ink jet containing a pigment. The solid content of the final preparation was about 9.2%. FIG. 3 is an electrical control block diagram of the above-described inkjet printer. 301 is a system controller for controlling the entire apparatus, including a microprocessor, a storage element (ROM) in which a control program is stored, and a storage element (RAM) used when the microprocessor performs processing. Etc. are arranged. Reference numeral 302 is a driver for driving the recording head in the main scanning direction, and similarly 303 is a driver for moving the print medium 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. A host computer 306 is a device for transferring information to be printed to the printing device of the present invention. Reference numeral 307 is a reception buffer for temporarily storing the data from the host computer 306, and stores the data until the data is read from the system controller 301. Reference numeral 308 denotes a frame memory for expanding the data to be printed into image data, and has a memory size required for printing one print medium. In this embodiment, a frame memory capable of storing one print medium will be described, but the present invention is not limited to the size of the frame memory. 309 is a storage element for temporarily storing data to be printed,
The storage capacity changes depending on the number of nozzles in the head.

Reference numeral 310 denotes an appropriate control of the head in response to a command from the system controller, which is a print control unit for controlling the print speed, the number of print data, etc., and further ejects the printability improving liquid. The data for this is also created. The system controller 301 and the print control unit 310 function as liquid ejection head control means for the printability improving liquid in the present invention. Reference numeral 311 denotes a driver for driving the recording head 312 s for ejecting the printability improving liquid and the head 312 k for ejecting ink, which is controlled by a signal from the print controller 310.

FIG. 4 illustrates a printing operation when a color image (including a mixture of black images) is printed by using the head 1k. FIG. 4A shows a black image printed with yellow ink. "Y", "M" printed with magenta ink, "printed with cyan ink"
An image with C ″ is shown. The process of printing this image is described below, but the printing operation for the printability improving liquid is omitted here for the sake of simplification during the description, and will be described later. Further, in the black image formation of FIGS. 4B to 4I, a solid image is printed on the entire surface in the drawings, but black ink is not actually ejected to the pixels corresponding to the color image. 4B, a black image is printed by the black ink nozzle 11k shown in Fig. 2. At this time, 24 nozzles are used, counting from the top in the figure. The medium is fed by 24 nozzles, and a black image is further printed by the black ink nozzles 11k as shown in Fig. 4C.
As shown in (d), a black image is printed by the nozzle 11k for black ink, and a part of "C" is printed by the nozzle 11c for cyan ink.

Subsequently, after feeding the print medium for 24 nozzles, as shown in FIG. 4 (e), the nozzles 11 for black ink are used.
Black image with k, "C" with cyan ink nozzle 11c
To print a part of. Then, after feeding the print medium for 24 nozzles, as shown in FIG. 4 (f), the remaining portion of "C" is changed by the nozzle 11c for cyan ink and the portion of "M" is changed by the nozzle 11m for magenta ink. Division (corresponding to the upper half)
To print. Then, after feeding the print medium by 24 nozzles, as shown in FIG. 4 (g), a part of "M" (corresponding to the lower half) of the magenta ink nozzle 11m is replaced by the yellow ink nozzle 11y. Print part of the "Y". Subsequently, after feeding the print medium for 24 nozzles, as shown in FIG.
After printing a part of "Y" with y and feeding the print medium, the remaining "Y" is printed with the nozzle 11y for yellow ink shown in FIG. 11 (i), and all the images are printed. finish.

As is clear from the above printing operation,
When the head used in this embodiment is used, the black image and the color image are not adjacent to each other in the same main scanning of the head. A black image and a color image are adjacent to each other in different scans. Among them, the color image that is closest to the black image earliest is the cyan image, and then the magenta image and the yellow image in this order. That is, when these three primary color images are adjacent to the black image, ink bleeding becomes noticeable in this order.

In consideration of the above characteristics, in this embodiment, the method of ejecting the printability improving liquid is changed depending on the print information of the color image adjacent to the black image. A specific example will be described with reference to FIG. . FIG. 5A shows an image when a color image is adjacent to a black image. FIG. 5B shows the ejection pattern of the printability improving liquid when the dots adjacent to the black image in the color image of FIG. 5A are composed of only yellow ink (yellow image). , The printability improving liquid is ejected to each one pixel on the adjacent boundary portion between the black image and the yellow image. Figure 5
FIG. 5C shows a case in which the dots adjacent to the black image in the color image of FIG. 5A are other than cyan ink and at least magenta ink dots are present (a magenta image or a red color due to a mixture of yellow and magenta). (Image), the discharge pattern of the printability improving liquid is shown, and the printability improving liquid is printed with a partial interval between each two pixels of the adjacent boundary portion between the black image and the color image. FIG. 5 (d) shows
When at least dots adjacent to the black image in the color image of FIG. 5A include cyan ink dots (cyan image or green image by mixing yellow and cyan, or blue image by mixing magenta and cyan) 2 shows the discharge pattern of the printability improving liquid, and the printability improving liquid is discharged to each two pixels of the adjacent boundary portion between the black image and the color image.

FIG. 6 shows a flow chart of the operation of this embodiment executed by the print controller. In step S1, the host computer 306 shown in FIG.
Data is transferred from, and the system controller 301 reads the data stored in the reception buffer 307. Next, in step 2, the black data among the data read in step 1 is focused on, and if there is color image data adjacent to the black image, it is determined whether or not the color dots adjacent to the black image are cyan dots. To do. If it is not adjacent to the cyan dot, then it is determined in step 4 whether or not the black image is adjacent to the magenta dot.
The printability improving liquid data is generated so as to have the pattern shown in (d). When it is determined in step 4 that the black image is adjacent to the magenta dot, the printability improving liquid data is generated in step 5 so as to have the pattern shown in FIG. When it is determined that the printability improving liquid is not adjacent to the magenta dot, the printability improving liquid data is generated in step 6 so as to have the pattern shown in FIG. In step 7, the printability improving liquid data is stored in the printability improving liquid buffer 309S, and the printing operation is performed in the next step 8. In the printing operation of step 8, the printability improving liquid is ejected to the pixels corresponding to the black image area at the boundary portion between the black image and the color image in the same scanning as the printing of the black image, while at the boundary portion. The ejection of the printability improving liquid onto the pixels corresponding to the color image area is performed by the same scanning as that for each color. For example, in FIG.
In printing "C" indicated by, the printing of the printability improving liquid corresponding to the black image area is performed in the same scanning as the black image, that is, in FIGS. 4B, 4C, 4D and 4E. And
The printability improving liquid is ejected to the pixels corresponding to the cyan image area in the same scanning as the cyan image, that is, in FIG.
The steps (e) and (f) are performed.

In the printed matter obtained in this manner, for example, the component amount of the printability improving liquid at the boundary between the black image and the cyan image is smaller than the component amount of the printability improving liquid at the boundary between the black image and the magenta image. There is more than that.

As described above, according to this embodiment,
In consideration of the time difference until the black image and each color image are adjacent to each other, the method of ejecting the printability improving liquid is changed according to the color information of the color image adjacent to the black image. As a result, it is possible to prevent ink bleeding between the black image and the color image while minimizing the use of the printability improving liquid, and it is possible to obtain a high-quality image.

(Embodiment 2) FIG. 7 is a schematic view of a color ink jet printer to which the present invention can be applied. The color ink head 1c and the black ink head 1 are shown.
k, a printability improving liquid head 1s, a carriage 2 on which each head is mounted, a flexible cable 3 for sending an electric signal from a printer body to a recording head, a cap unit 4 having a recovery means, heads 1c, 1k, 1s, respectively. It has corresponding cap members 5c, 5k, 5s, a wiper blade 6 made of a member such as rubber, a feeding tray 8 for feeding the print medium 7, and the like.

FIG. 8 shows the structure of the nozzles of the heads 1s, 1k, 1c, and is a schematic view when viewed from the ink ejection port side. The head 1s is provided with 160 nozzles 111s for ejecting the printability improving liquid. Further, the head 1k is provided with 160 nozzles 111k for ejecting black ink. Further, the head 1c is provided with 48 nozzles 111y for ejecting yellow ink, 48 nozzles 111m for ejecting magenta ink, and 48 nozzles 111c for ejecting cyan ink. Further, a space for 8 nozzles is provided between the nozzles of each color.

1 from each nozzle of the heads 1s and 1c
About 40 ng of the printability improving liquid or color ink is ejected per droplet, and about 80 ng of black ink is ejected from the nozzle of the head 1k. In this example, the printability improving liquid and ink having the same composition as in Example 1 were used.

FIG. 9 illustrates the printing operation when printing a color image (including a mixture of black images) using the heads 1k and 1c, and FIG.
The image is basically the same as that printed in Example 1. In the black image formation of FIGS. 9B to 9G, a solid image is printed on the entire surface in the drawings, but black ink is not actually ejected to the pixels corresponding to the color image.

In FIG. 9B, the nozzle 111 for black ink is used.
A black image is printed by k. At this time, 48 nozzles are used, counting from the bottom in the figure. After printing is completed, the print medium is fed by 48 nozzles, as shown in FIG.
As shown in FIG. 5, a black image is further printed by the black ink nozzle 111k, and a part of "C" (corresponding to the upper half) is printed by the cyan ink nozzle 111c.

Then, after feeding the print medium for 48 nozzles, as shown in FIG. 9D, the nozzle 11 for black ink is used.
A black image at 1k is printed by the cyan ink nozzle 111c.
The remaining portion of C "(corresponding to the lower half) is printed with a part of" M "by the nozzle 111m for magenta ink. Subsequently, after feeding the print medium for 48 nozzles, as shown in FIG. 9F, a black image is printed by the black ink nozzle 111k, a part of "M" is printed by the magenta ink nozzle 111m, and a part of "Y" is printed by the yellow ink nozzle 111y. ), The remaining portion of "M" is printed by the nozzle 111m for magenta ink and a part of "Y" is printed by the nozzle 111y for yellow ink.
Then, after feeding the print medium for 48 nozzles, the remaining "Y" is printed by the nozzles 111y for yellow ink, and the printing of all the images is completed.

FIG. 10 shows the discharge pattern of the printability improving liquid when the black image is adjacent to the color image. The difference from FIG. 5 of the first embodiment is that the color inks are adjacent to the black image. It is faster than in the first embodiment. Therefore, the area for ejecting the printability improving liquid is wider than that in the first embodiment, and the ejection amount of the printability improving liquid is increased. FIG. 10B shows an ejection pattern of the printability improving liquid when the dots adjacent to the black image in the color image of FIG. 10A are composed of only yellow ink (yellow image). Similarly to the first embodiment, the printability improving liquid is discharged to each one pixel of the adjacent boundary portion between the black image and the yellow image.

FIG. 10C shows a case in which the dots adjacent to the black image in the color image of FIG. 10A are other than cyan ink and there are at least magenta ink dots (magenta image or yellow and magenta). (Red image due to mixed color), the dischargeability of the printability improving liquid is shown, and the printability improving liquid is discharged to each two pixels at the adjacent boundary portion between the black image and the color image.

FIG. 10D shows a case where at least dots adjacent to the black image in the color image of FIG. 10A are cyan ink dots (a cyan image or a green image obtained by mixing yellow and cyan or The pattern of the printability improving liquid for a blue image (a mixture of magenta and cyan) is shown, and the printability improving liquid is discharged for each three pixels at the adjacent boundary portion between the black image and the color image.

The electrical control block diagram and operation flow of this embodiment are basically the same as those of the first embodiment, and therefore their explanations are omitted. When a color image is printed by the color inkjet printer described above, a clear color image is obtained in which feathering does not occur with respect to a black image and bleeding between colors does not occur between the black image and the color images. I was able to.

Although the first and second embodiments have been described with respect to the example in which the pixels are printed on both the pixels at the boundary between the black image portion and the color image portion, from the time the black image is printed until the color images are adjacent to each other. In the case of so-called multi-pass printing in which the image is thinned out in a predetermined pattern and formed by a plurality of scans, the ink is printed between the black and color images even if they are adjacent to each other. The amount of ink that has penetrated into the inside of the print medium and is present on the surface of the print medium decreases, so that ink bleeding is relatively unlikely. In such a case, the printability improving liquid can be ejected only on one of the black image and the color image to further suppress the consumption of the printability improving liquid.

Also, a pattern for ejecting the printability improving liquid.
The pattern may be a pattern in which a part corresponding to a black image or a color image is thinned out and ejected as shown in FIGS. 11 (a), (b), (c) and (d). The reason is that the color ink contains a surfactant so that the composition has a relatively high permeation rate with respect to the print medium, while the black ink does not contain a surfactant and has a relatively high penetration rate with respect to the print medium. When the composition having a slow penetration speed is used, the surfactant in the color ink migrates to the black ink area at the adjacent boundary portion between the color ink and the black ink, and the black ink penetrates into the print medium at this portion to appear whitish. In some cases, this phenomenon can be reduced by discharging a large amount of the printability improving liquid to the black area side as shown in FIGS. 11C and 11D.

Further, in the first and second embodiments, the color ink is ejected from one head, but a head having a structure as shown in FIG. 12 may be used. This head is provided with a nozzle 201 for a printability improving liquid.
s, a nozzle 201k for black ink and a nozzle 201c for cyan ink, and a nozzle 20 for magenta ink
1 m and a nozzle 201y for yellow ink. With this configuration, since the black dots and the magenta dots are printed in the same scan, the discharge pattern for the printability improving liquid is shown in FIG. 10D, and the yellow dots and the cyan dots are printed in different scans. Therefore, the pattern for the printability improving liquid is as shown in FIG.
(C) may be used.

Further, in the above embodiment, the ejection pattern of the printability improving liquid is determined by determining whether or not the image adjacent to the black image contains, for example, magenta dots. The ejection pattern of the printability improving liquid may be further divided according to whether only the magenta dots or both the magenta dots and the yellow dots are included. That is, since the amount of ink to be ejected differs depending on whether the dots adjacent to the black image are the primary colors of yellow, magenta, and cyan, or the secondary colors of red, blue, and green, the secondary color with a large amount of ink to be ejected. In this case, the area for ejecting the printability improving liquid may be widened.

According to the above-described examples, a black ink, a plurality of color inks other than black, and a printability improving liquid applied to improve printability in ink jet printing were used to print on a print medium. The printability improving liquid, which is a printed matter, wherein a black image area formed by a black ink on a print medium and a color image area formed by a color ink other than the black are present in at least a part of a boundary portion adjacent to each other. The amount of the component per unit area of the printability improving liquid present in at least a part of the boundary portion where the black image region and the color image region formed by another color ink are adjacent to each other, and It was possible to obtain a printed matter characterized by different things. The printed matter obtained in this manner had very little ink bleeding at the boundary between the black image and the color image, and the image was of high quality.

(Others) In the present invention, particularly in the ink jet recording system, means for generating thermal energy as energy used for ejecting ink (for example, an electrothermal converter or laser light). ), And brings about an excellent effect in a recording head and a recording apparatus of a system in which a change in ink state is caused by the thermal energy. This is because such a system can achieve high density recording and high definition recording.

With regard to its typical structure and principle, for example, US Pat. Nos. 4,723,129 and 4740 are applicable.
What is done using the basic principles disclosed in 796 is preferred. This method can be applied to both the so-called on-demand type and continuous type, but especially in the case of the on-demand type, liquid (ink)
At least one drive signal corresponding to recorded information and giving a rapid temperature rise exceeding nucleate boiling is applied to the electrothermal converter arranged corresponding to the sheet or liquid path in which is stored. As a result, the heat energy is transferred to the electrothermal converter.
Is effective to cause film boiling on the heat acting surface of the recording head, and as a result, bubbles can be formed in the liquid (ink) corresponding to this drive signal in a one-to-one correspondence. 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 bubbles can be immediately and appropriately grown and contracted, so that liquid (ink) ejection with excellent responsiveness can be achieved.

As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 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, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned respective specifications. A configuration using US Pat. No. 4,558,333 or US Pat. No. 4,459,600, which discloses a configuration in which the heat acting portion is arranged in the bending region, may be used.

In addition, Japanese Unexamined Patent Publication No. 59-123670 discloses a structure in which a common slit is used as a discharge portion of the electrothermal converter for a plurality of electrothermal converters.
It is also possible to adopt a configuration based on Japanese Patent Application Laid-Open No. 59-138461, which discloses a configuration in which the opening for absorbing the pressure wave of (1) corresponds to the discharge portion. That is, according to the present invention, recording can be surely and efficiently performed regardless of the form of the recording head.

Furthermore, 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. As such a recording head, a combination of a plurality of recording heads satisfies the length,
Any of the configurations as one recording head may be used.

In addition, even in the case of the serial type as described above, the recording head fixed to the main body of the apparatus or the electrical connection with the main body of the apparatus and the supply of ink from the main body of the apparatus by being attached to the main body of the apparatus. It is also possible to use a replaceable chip type recording head capable of performing the above or a cartridge type recording head in which an ink tank is integrally provided in the recording head itself.

Further, it is preferable to add recovery means, preliminary auxiliary means, etc. to the recording head because the effects of the present invention can be further stabilized. Specific examples thereof include capping means, cleaning means, pressurizing or suctioning means for the recording head, preheating means using an electrothermal converter or another heating element or a combination thereof, and recording. It is also effective to perform stable recording by performing a preliminary discharge mode for performing discharge different from the above.

In addition, in the above-described embodiments of the present invention, the ink is described as a liquid, but it is an ink that solidifies at room temperature or lower and that softens at room temperature or is a liquid. Or, in the above-mentioned inkjet method, it is general that the temperature of the ink itself is adjusted within a range of 30 ° C. or higher and 70 ° C. or lower to control the temperature of the ink so that the viscosity of the ink is within a stable ejection range. It is sufficient that the ink is in a liquid state when applied.

In addition, the temperature rise due to the thermal energy is positively prevented by being used as the energy for changing the state of the ink from the solid state to the liquid state, or the ink is left standing for the purpose of preventing the evaporation of the ink. Either using solidifying ink, the ink is liquefied by application of thermal energy according to the recording signal, and ejected as liquid ink, or the one that already begins to solidify when it reaches the recording medium, etc. The use of an ink having the property of being liquefied only by thermal energy as described above is also applicable to the present invention. In such a case, the ink is disclosed in JP-A-54-5684.
No. 7 or JP-A No. 60-71260, so as to face the electrothermal converter in the state of being held as a liquid or a solid in the recesses or through holes of the porous sheet. It may be in any form. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

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

FIG. 13 is a block diagram showing a schematic configuration when the recording apparatus of the present invention is applied to an information processing apparatus having the functions of a word processor, a personal computer, a facsimile machine and a copying machine. .

In the figure, reference numeral 1801 denotes a control unit for controlling the entire apparatus, which includes a CPU such as a microprocessor and various I / Os.
It is equipped with a port and outputs control signals and data signals to each section and inputs control signals and data signals from each section for control. A display unit 1802 displays various menus, document information, image data read by the image reader 1807, and the like.
A transparent pressure-sensitive touch panel 1803 is provided on the display unit 1802. By pressing the surface of the touch panel 1803 with a finger or the like, items or coordinate positions can be input on the display unit 1802.

1804 is an FM (Frequency M)
sound source section, the music information created by a music editor or the like is stored in the memory section 1810 or the external storage device 18
The data is stored as digital data in 12, and is read from the memory or the like to perform FM modulation. FM
The electric signal from the sound source unit 2804 is converted into an audible sound by the speaker unit 1805. The printer unit 1806 has the recording apparatus according to the present invention applied as an output terminal of a word processor, a personal computer, a facsimile apparatus, and a copying apparatus.

Reference numeral 1807 denotes an image reader unit for photoelectrically reading and inputting original data, which is provided in the middle of the original conveying path and reads various originals in addition to facsimile originals and copy originals. Reference numeral 1808 denotes a facsimile transmission of original data read by the image reader unit 1807,
It is a facsimile transmission / reception unit that receives and decodes a transmitted facsimile signal and has an interface function with the outside. Reference numeral 1809 denotes a telephone unit having various telephone functions such as a normal telephone function and an answering machine function.

Reference numeral 1810 denotes a ROM for storing a system program, a manager program, other application programs, etc., a character font, a dictionary, etc.
It is a memory unit including a RAM for storing the application program and character information loaded from the external storage device 1812, a video RAM, and the like.

Reference numeral 1811 is a keyboard section for inputting document information and various commands. An external storage device 1812 uses a floppy disk, a hard disk, or the like as a storage medium. The external storage device 1812 stores character information, music or voice information, a user application program, and the like.

FIG. 14 is an external view of the information processing apparatus shown in FIG. In the figure, reference numeral 1901 denotes a flat panel display using liquid crystal or the like, which displays various menus, graphic information, document information and the like. A touch panel 1803 is installed on the display 1901. By pressing the surface of the touch panel 1803 with a finger or the like, coordinate input or item designation input can be performed. 1902 is a handset used when the device functions as a telephone.

The keyboard 1903 is detachably connected to the main body via a code, and various character information and various data are stored.
Data can be input. Also, this keyboard 19
03 is provided with various function keys 1904 and the like. 1
Reference numeral 905 is an insertion port of a floppy disk into the external storage device 1812.

Reference numeral 1906 denotes a paper placing portion on which an original read by the image reader 1807 is placed, and the read original is discharged from the rear of the apparatus. When receiving a facsimile or the like, the image is recorded by the inkjet printer 1907.

The display 1802 is a CRT.
However, a flat panel such as a liquid crystal display using a ferroelectric liquid crystal is preferable. This is because in addition to being small and thin, it is possible to reduce the weight. When the information processing device functions as a word processor, the keyboard shown in FIG. 13 is used.
The character information input from the control unit 1811 is the control unit 1801.
Is processed according to the document processing program and output as an image to the printer unit 1806.

The above information processing apparatus is a personal computer.
In the case of functioning as data, various data input from the keyboard section 1811 are calculated by the control section 1801 in accordance with the application program, and the printer section 1811.
The calculation result is output as an image in 06.

When functioning as a receiver of a facsimile apparatus, a facsimile transmission / reception unit 1808 is provided via a communication line.
The facsimile information input from the printer unit 1 is received by the control unit 1801 according to a predetermined program, and the printer unit 1
The received image is output to 806.

In the case of functioning as a copying machine, a document is read by the image reader unit 1807, and the read document data is transferred to the printer unit 1 via the control unit 1801.
It is output to 806 as a copied image. When functioning as a transmitter of a facsimile machine, document data read by the image reader unit 1807 is stored in the control unit 1.
After transmission processing according to a predetermined program by 801 is performed, it is transmitted to the communication line via the facsimile transmission / reception unit 1808.

The above-mentioned information processing apparatus may be an integrated type in which an ink jet printer is built in the main body as shown in FIG. 15, and in this case, it becomes possible to further enhance the portability. In the figure, parts having the same functions as those in FIG. 14 are designated by the corresponding reference numerals.

By applying the recording apparatus of the present invention to the multifunctional information processing apparatus described above, it is possible to obtain a high-quality recorded image, so that it is possible to further improve the function of the information processing apparatus. Become.

[0085]

As described above, according to the present invention,
Considering the time difference until the black image and each color image are adjacent to each other, by changing the ejection area of the printability improving liquid ejected to the adjacent boundary area, it is possible to obtain the black image with the minimum necessary printability improving liquid amount. It is possible to reduce image deterioration due to ink bleeding at the boundary with the color image and form a high-quality image.

[Brief description of drawings]

FIG. 1 is a perspective view showing an inkjet printing apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram for explaining the head according to the first embodiment.

FIG. 3 is an electrical control block diagram of the inkjet printing apparatus according to the first embodiment.

FIG. 4 is a diagram illustrating a printing process according to the first embodiment.

FIG. 5 is a diagram illustrating an ejection pattern of a printability improving liquid in Example 1.

FIG. 6 is a flowchart showing the operation of the inkjet printing apparatus according to the first embodiment.

FIG. 7 is a schematic diagram of an inkjet printing apparatus according to a second embodiment.

FIG. 8 is a diagram for explaining a head according to a second embodiment.

FIG. 9 is a diagram illustrating a printing process according to a second embodiment.

FIG. 10 is a diagram illustrating a discharge pattern of a printability improving liquid in Example 2.

FIG. 11 is a diagram illustrating another example of the discharge pattern of the printability improving liquid.

FIG. 12 is a diagram for explaining another example of the head.

FIG. 13 is a block diagram showing an example of an information processing system using the inkjet printing apparatus of each of the above embodiments.

FIG. 14 is an external perspective view of the system.

FIG. 15 is an external view showing another example of the system.

[Explanation of symbols]

 1s, 1k, 1c, 312s, 312k head 301 system controller 302, 303 driver 304, 305 motor 307 reception buffer 308 frame memory 309 storage element 309s buffer 310 print control unit 311 head driver

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Minoko Kato 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (7)

[Claims] 1. An ink ejection head for ejecting black ink and a plurality of color inks other than black, a black image area formed by the black ink on a print medium, and the color ink other than black. Printing is performed on a print medium using a liquid ejection head that ejects a printability improving liquid for improving printability in inkjet printing on at least a part of a boundary portion where the color image region is adjacent to the black image region. In the inkjet printing apparatus, the time from the formation of one of the color image area to the formation of the other image area via the boundary portion is different depending on the type of the color ink, and the black image area and Time from the formation of one of the color image areas to the formation of the other image area via the boundary There wherein with relatively short color ink color -
A liquid that increases the amount of the printability-improving liquid ejected onto at least a part of the boundary portion when forming the image region, as compared with the case where the color image region is formed by using the color ink having a relatively long time. An inkjet printing apparatus comprising an ejection head control means. 2. The ink jet printing apparatus according to claim 1, wherein the printability improving liquid contains a cationic substance having a low molecular weight component and a high molecular weight component, and the ink contains an anionic dye. 3. The printability improving liquid contains a low molecular component and a high molecular component cationic substance, and the ink contains an anionic compound and a pigment.
The inkjet printing apparatus described. 4. The ink ejecting head and the liquid ejecting head are heads for ejecting ink or a printability improving liquid by utilizing heat energy, and generate heat energy to be given to the ink or the printability improving liquid. 2. A thermal energy generator for controlling the temperature of the object.
4. The inkjet printing apparatus according to any one of 3 to 3. 5. A boundary in which black ink, a plurality of color inks other than black, a black image area formed by the black ink and a color image area formed by the color ink other than black are adjacent to each other on a print medium. After printing on a print medium using a printability improving liquid applied to improve printability in at least a part of an inkjet print, one of the black image area and the color image area is formed. An inkjet printing method in which the time until the other image area is formed via the boundary portion is different depending on the type of the color ink, and after the one of the black image area and the color image area is formed, The color ink is used for a relatively short time until the other image area is formed through the boundary portion.
In the case of forming the image area, the amount of the printability improving liquid ejected onto at least a part of the boundary portion is made larger than in the case of forming the color image area by using the color ink having a relatively long time. An inkjet printing method characterized by: 6. A black ink, a plurality of color inks other than black, and a printability improving liquid which is applied to improve printability in inkjet printing,
A printed matter printed on a print medium, wherein a black image area formed by a black ink on the print medium and a color image area formed by a color ink other than the black are present in at least a part of a boundary portion adjacent to each other. The amount of the component per unit area of the printability improving liquid is a unit of the printability improving liquid present in at least a part of a boundary portion where the black image region and the color image region formed by another color ink are adjacent to each other. Printed matter characterized by different amount of components per area. 7. The printed matter according to claim 6, which is printed by the inkjet printing method according to claim 5.