JP3843633B2 - Inkjet recording device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ink jet recording apparatus.
[0002]
[Prior art]
With the widespread use of information devices such as word processors and computers, recording devices that perform digital image recording using an ink-jet recording head are becoming popular as one of recording devices for these devices. Furthermore, with the advancement of performance and accuracy of these information devices, there is an increasing demand for higher image quality and colorization in the recording apparatus.
[0003]
However, in order to obtain a high-quality color image, it is necessary to use a special paper having an absorption layer that prevents ink bleeding and enhances color developability, especially when color printing is performed on plain paper. There are problems such as deterioration of image quality due to, and insufficient water resistance and light resistance. In particular, a black image such as a monochrome sentence created by a word processor or the like is required to have a clear image without bleeding and a high black density, so that the black ink is suppressed as much as possible and is recorded at the highest possible density. Is preferred. Furthermore, practically sufficient water resistance and light resistance are desired.
[0004]
Usually, an ink for recording a color image by an ink jet recording apparatus uses a water-soluble dye which is a color material having high transparency and high color reproducibility, and is a quick-drying ink having a high penetration speed into recording paper. Is used.
[0005]
When ink of such a composition is used, the special paper has an absorption layer, so there is no bleeding and both the color image and the black image can obtain the desired image quality. There is no problem with water resistance. However, in plain paper, a color image is mixed to form a color, so that it is difficult to be affected by bleeding and a desired image quality can be obtained. However, black images are greatly affected by bleeding and the density is low. Therefore, there remains a problem that a desired image quality cannot be obtained. Further, there is a problem that even if it is sufficiently dried after recording, a practically sufficient water resistance cannot be obtained, and further, a sufficient light resistance cannot be obtained.
[0006]
In order to improve the quality of black images on plain paper, there is a method of recording on plain paper using pigment black ink using a pigment as a color material. By using the pigment black ink, it is possible to obtain a clear black image with suppressed bleeding on plain paper, practically sufficient water resistance and light resistance, and to obtain a desired black image. is there. However, it has been confirmed that glossiness peculiar to the pigment black ink occurs in the special paper due to the characteristics of the absorption layer and the pigment black ink. In particular, when a color image portion recorded using a water-soluble dye ink and a black image portion recorded using a pigment black ink are mixed, the glossiness differs only in the black image portion, so that the overall feeling of strangeness is felt. There is a problem that it becomes a certain image.
[0007]
As a solution to such a problem, there is a method of recording by using two types of black inks together in a conventional ink jet recording apparatus.
[0008]
For example, in Japanese Patent Application Laid-Open No. 7-125406, a recording head that discharges color ink and first black ink having a relatively high penetration speed, and a second that has a relatively low penetration speed than the first black ink. When recording on plain paper using a recording head that discharges black ink, the first black ink is used when the black image is adjacent to the color image, and the second black ink is used when the black image is not adjacent. A method of recording an image with less blur is provided by a method of recording an image.
[0009]
In Japanese Patent Application Laid-Open No. 8-267903, a black ink containing a water-soluble black dye and a black pigment as color materials and containing a liquid medium in which these color materials are dissolved or dispersed is applied to an image forming area. There is provided a method for improving water resistance by a process and a method of forming an image by a process of applying a liquid composition containing no color material different from the black ink to the image forming region.
[0010]
[Problems to be solved by the invention]
However, in such a conventional technique example, as disclosed in, for example, Japanese Patent Laid-Open No. 7-125406, the recording method using the second black ink with a slow penetration time is clear on plain paper. Although a black image can be obtained, the rubbing resistance immediately after printing deteriorates due to the delay in drying time due to the slow penetration speed, so the recording paper cannot be continuously stacked and is not suitable for high-speed printing. There is. In addition, if a water-soluble dye is used as a coloring material, there still remains a problem that sufficient water resistance cannot be obtained.
[0011]
Further, for example, in the image forming method disclosed in Japanese Patent Application Laid-Open No. 8-267903, it is possible to obtain both high quality black images of dedicated paper and plain paper and to improve water resistance of plain paper. However, there is a problem that the black ink and the liquid composition different from the black ink have an increase in cost and the complexity of the recording apparatus, and the black ink recording process and the liquid composition different from the black ink There are problems such as an increase in the number of recording steps and complication of the recording process due to having to have the recording process.
[0012]
Accordingly, an object of the present invention is to provide an ink jet recording apparatus capable of obtaining a desired black image on dedicated paper and plain paper.
[0013]
[Means for Solving the Problems]
The inkjet recording apparatus of the present invention uses a recording head having a plurality of nozzle groups, and discharges ink from the plurality of nozzle groups moving in the main scanning direction to perform recording on recording paper. Has a first black nozzle group for ejecting a first black ink having a water-soluble dye as a color material, and a second black nozzle group for ejecting a second black ink having a pigment as a color material. When forming a black image on the recording paper, if the recording paper is plain paper, the ink droplets of the first black ink and the ink droplets of the second black ink are adjacent in the sub-scanning direction. The ink jet recording apparatus is characterized in that the recording head further includes a color nozzle group for discharging a color ink having a water-soluble dye as a color material, The nozzle group, the first black nozzle group, and the second black nozzle group are arranged in the recording head side by side in the main scanning direction, and the color nozzle group, the first black nozzle group, and the second black nozzle group are arranged. Each of the black nozzle groups includes a plurality of nozzles arranged at a predetermined pitch along the sub-scanning direction, and the second black nozzle group is in relation to the color nozzle group and the first black nozzle group. In the case of forming a color image on the recording paper that is displaced in the sub-scanning direction, the ink is ejected from the color nozzle group and the first black nozzle group, and the ink is ejected at intervals of the pitch in the sub-scanning direction. Drops are ejected onto the recording paper, the recording paper is transported, and ink is ejected from the color nozzle group and the first black nozzle group between the ink droplets that are ejected at the intervals, thereby recording the ink droplets. On paper In the case where a color image with a predetermined resolution is formed to form a black image on the recording paper, and the recording paper is plain paper, the first black nozzle group and the second black nozzle Ink is ejected from the group, and the second black ink droplet is driven between the first black ink droplets to form a black image of the resolution.
[0014]
Also, in an ink jet recording apparatus that uses a recording head having a plurality of nozzle groups and ejects ink from the plurality of nozzle groups moving in the main scanning direction to perform recording on recording paper, the recording head is a water-soluble colorant. A first black nozzle group that ejects a first black ink having a sexual dye, and a second black nozzle group that ejects a second black ink having a pigment as a colorant, on the recording paper When forming the black image, if the recording paper is plain paper, the first black ink droplet and the second black ink droplet are driven onto the recording paper adjacent to each other in the sub-scanning direction. The recording head further includes a color nozzle group for discharging a color ink having a water-soluble dye as a coloring material, and the inkjet recording apparatus Color separation means for separating the data into black image data and color image data, black image data storage means and color image data storage means for storing the separated recording data, and paper type information of the recording paper According to the paper type information storage means and the paper type information, the first black ink and the second black ink are discharged simultaneously or selectively from the first black nozzle group and the second black nozzle group. And a black nozzle driving unit that generates a driving signal for generating a driving signal for ejecting the color ink from the color nozzle group.
[0015]
The black nozzle driving means generates a drive signal for ejecting the first black ink from the first black nozzle group when the recording paper for forming the black image is a dedicated paper. When the recording paper for forming the black image is plain paper, the first black ink and the second black ink are simultaneously applied from the first black nozzle group and the second black nozzle group. A drive signal to be ejected is generated.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on examples.
[0017]
FIG. 1 is a diagram showing an outline of an ink jet recording apparatus of the present invention.
[0018]
The recording head 101 is transported in the main scanning direction indicated by arrows A and B along the guide shaft 109 by a carriage driving belt 103 fixed to the carriage 102 and driven by a carriage driving motor 104. The recording paper 107 is conveyed in the direction of arrow C by a conveyance roller 108 driven by a conveyance roller drive motor (not shown). Ink forming the recording pixels is supplied from the ink supply tank 105 to the recording head 101 through the ink supply pipe 106.
[0019]
The recording head 101 is an ink jet recording head using a piezoelectric element, and a plurality of nozzles are arranged in an arbitrary matrix or in a single row in the sub-scanning direction (the direction of the arrow C).
[0020]
FIG. 3 is a diagram illustrating the nozzle group of the recording head 101 in this embodiment. The recording head 101 has a first black nozzle group 301, a second black nozzle group 302, and three color nozzle groups 303 of C, M, and Y in the main scanning direction. It consists of 32 nozzles arranged at a 1/180 inch pitch in the scanning direction. Further, the second black nozzle group 302 is arranged with a 1/360 inch pitch shift in the sub-scanning direction with respect to the first black nozzle group 301.
[0021]
When the recording head 101 having such a configuration is used, recording in the sub-scanning direction 360 dpi is possible by scanning the recording head 101 twice. Further, the first black nozzle group 301 and the second black nozzle group 302 are driven simultaneously to perform recording, whereby recording in the sub-scanning direction 360 dpi is possible with one scan.
[0022]
Further, in the recording head 101 in this embodiment, as the color ink and the first black ink, for example, dye 3 wt%, glycerin 10 wt%, acetylene glycol surfactant 1 wt%, diethylene glycol butyl ether 5 wt%, and the remainder Ink made of pure water is used. Further, as the second black ink, for example, carbon black-based black pigment 3 wt%, glycerin 10 wt%, acetylene glycol-based surfactant 1 wt%, diethylene glycol butyl ether 5 wt%, and the balance consisting of pure water are used. .
[0023]
Next, the recording operation will be described.
[0024]
Prior to the recording operation, the recording paper 107 is fed to a position facing the nozzle surface of the recording head 101 by a paper feeding device (not shown). The recording head 101 selectively ejects ink droplets from the nozzles of the recording head 101 in synchronization with scanning of the carriage 102 to inject ink droplets onto the recording paper 107, and characters and images based on the recording data are displayed on the recording paper 107. Formed at a predetermined position. At the end of this scanning, the recording paper 107 is conveyed in the sub-scanning direction by the conveying roller 108. By repeating this operation, desired characters and images are formed on the recording paper.
[0025]
The amount of movement of the recording head 101 in the main scanning direction and the amount of conveyance of the recording paper 107 in the sub-scanning direction are determined according to the recording resolution.
[0026]
FIG. 4 is a diagram showing a recording operation when recording at a resolution of 360 dpi in the present embodiment. The recording head 101 selectively ejects ink droplets each time it moves 1/360 inch while being scanned in the main scanning direction by the carriage 102. The recording paper 107 is conveyed 1/360 inch by the conveying roller 108 when the scanning of the recording head 101 is completed. After repeating the scanning operation of the recording head 101 and the conveying operation of the recording paper 107 twice, a series of conveying operations of conveying the recording paper 107 63/360 inches are repeated, so that a desired 360 dpi on the recording paper 107 is obtained. Record data is formed. The nozzle groups used at this time are the first black nozzle group 301 and the color nozzle group 303.
[0027]
FIG. 5 is a diagram showing another recording operation when recording at a resolution of 360 dpi in the present embodiment. The recording head 101 selectively ejects ink droplets each time it moves 1/360 inch while being scanned in the main scanning direction by the carriage 102. The recording paper 107 is conveyed 64/360 inches by the conveying roller 108 when the scanning of the recording head 101 is completed. By repeating this series of transport operations, desired 360 dpi recording data is formed on the recording paper 107. The nozzle groups used at this time are the first black nozzle group 301 and the second black nozzle group 302.
[0028]
FIG. 2 is a block diagram showing the configuration of the ink jet recording apparatus according to one embodiment of the present invention. The inside of the broken line in the figure shows the configuration of the ink jet recording apparatus according to this embodiment.
[0029]
The ink jet recording apparatus according to this embodiment includes a color separation unit 201 that separates recording data 211 into black image data and color image data, and a black image that stores the black image data and color image data separated by the color separation unit 201. Data storage means 202, color image data storage means 203, paper type information storage means 204 for storing paper type information 212 of the recording paper, and the first black ink and the second black ink in accordance with the paper type information 212. , Black nozzle driving means 205 for generating a drive signal for discharging simultaneously or selectively from the first black nozzle group 301 and the second black nozzle group 302, and the color ink to the color nozzle group 302. Color nozzle driving means 206 for generating a driving signal for discharging from the recording head 101 and the recording head 101 And, a CPU (not shown) for controlling them.
[0030]
Next, the operation of the ink jet recording apparatus in this embodiment will be described.
[0031]
The recording data 211 transferred from the external device 210 is separated into black image data 213 and color image data 214 by the color separation means 201. The separated recording data is stored in the black image data storage unit 202 and the color image data storage unit 203, respectively. In this embodiment, by reading the color information contained in the recording data 211, it is possible to separate the recording data into black image data and color image data.
[0032]
The paper type information 212 of the recording paper transferred from the external device 210 is stored in the paper type information storage unit 204 in advance.
[0033]
The black image data 213 stored in the black image data storage unit 202 is sent to the black nozzle driving unit 205 as recording starts. The black nozzle driving unit 205 receives the black image data 213 and generates a head driving signal for recording in accordance with the paper type information 212 stored in the paper type information storage unit 204. Thereafter, the black nozzle driving unit 205 assigns and applies the generated head driving signal to the respective nozzles of the first black nozzle group 301 and the second black nozzle group 302 of the recording head 101. The first black nozzle group 301 and the second black nozzle group 302 eject ink droplets in accordance with the drive signal applied by the black nozzle driving means 205 to form a desired black image on the recording paper 107.
[0034]
The color image data 214 stored in the color image data storage unit 203 is sent to the color nozzle driving unit 206 at the same time as recording is started. The color nozzle driving unit 206 receives the color image data 214 and generates a head driving signal for recording. Thereafter, the color nozzle driving means 206 assigns and applies the generated head driving signal to each nozzle of the color nozzle group 303 of the recording head 101. The color nozzle group 303 ejects ink droplets according to the drive signal applied by the color nozzle drive unit 206 to form a desired color image on the recording paper 107.
[0035]
Here, the black image data recording operation will be described.
[0036]
In this embodiment, for example, when recording is performed in the recording operation shown in FIG. 4, when the recording paper is used, the black nozzle driving unit 205 outputs a drive signal for recording the black image data 213 to the first signal. By assigning and applying to each nozzle of one black nozzle group 301, black image data can be recorded using the first black ink. As a result, it is possible to obtain a desired image that does not feel uncomfortable even if a black image and a color image are mixed on dedicated paper.
[0037]
Also, for example, when recording is performed by the recording operation shown in FIG. 4, when the recording paper is plain paper, black image data is recorded as follows.
[0038]
When black image data and color image data are mixed in the recording data, the black nozzle driving means 205 sends a driving signal for recording the black image data 213 to each nozzle of the first black nozzle group 301. Thus, it is possible to record black image data using the first black ink. As a result, it is possible to obtain a desired image that does not feel strange even if a black image and a color image are mixed on plain paper.
[0039]
When the recording data is only black image data, the black nozzle driving unit 205 assigns and applies a driving signal for recording the black image data 213 to each nozzle of the second black nozzle group 302. Thus, it is possible to record black image data using the second black ink. As a result, the black image data makes it possible to obtain a clear, high-density and high-quality image, and to obtain sufficient water resistance and light resistance.
[0040]
Further, for example, when recording is performed by the recording operation shown in FIG. 5, the black nozzle driving means 205 outputs a driving signal for recording the black image data 213 as the first black nozzle group 301 and the second black nozzle data. By assigning and applying to each nozzle of the black nozzle group 302, it is possible to record black image data using the first black ink and the second black ink simultaneously. As a result, since the first black ink and the second black ink are mixed, a clear and high-density black image is obtained at a high speed, although it is inferior to the image quality when recording with only the second black ink. It is also possible to obtain high water resistance and light resistance.
[0041]
FIG. 6 is a diagram showing an operation flow of the ink jet recording method according to one embodiment of the present invention. This operation flow shows the operation flow of the recording method in the recording operation shown in FIG.
[0042]
STEP 1 is the first step in which recording data is transferred from an external device.
[0043]
STEP 2 is a step of separating the recording data into black image data and color image data. When the recording data is black image data, the process proceeds to STEP 3 and the black image data is stored in the black image data buffer. If the recording data is not black image data, that is, if it is color image data, the process proceeds to STEP 4, the color image data is stored in the color image data buffer, and then the process proceeds to STEP 9.
[0044]
STEP 5 is a step of determining the paper type based on the paper type information stored in advance in the paper type information buffer.
[0045]
When it is determined that the recording paper is the exclusive paper in the determination step of STEP5, the process proceeds to STEP6 and it is determined to record the black image data stored in the black image data buffer with the first black ink. Then, go to STEP9.
[0046]
If it is determined in STEP 5 that the recording sheet is plain paper, the process proceeds to STEP 7 and it is determined whether or not there is color image data in the color image data buffer.
[0047]
If it is determined in step 7 that there is color image data, the process proceeds to step 6 and it is decided to record the black image data stored in the black image data buffer with the first black ink. Then, go to STEP9.
[0048]
If it is determined in step 7 that there is no color image data, the process proceeds to step 8 to record the black image data stored in the black image data buffer with the second black ink. After the determination, go to STEP9.
[0049]
In STEP 9, the recording operation is performed by the recording head 101 using the black ink and the color ink determined in the above process.
[0050]
FIG. 7 is a diagram showing an operation flow of an ink jet recording method according to another embodiment of the present invention. This operation flow shows the operation flow of the recording method in the recording operation shown in FIG.
[0051]
STEP 1 is the first step in which recording data is transferred from an external device.
[0052]
STEP 2 is a step of separating the recording data into black image data and color image data. When the recording data is black image data, the process proceeds to STEP 3 and the black image data is stored in the black image data buffer. If the recording data is not black image data, that is, if it is color image data, the process proceeds to STEP 4, the color image data is stored in the color image data buffer, and then the process proceeds to STEP 9.
[0053]
STEP 5 is a step of determining the paper type based on the paper type information stored in the paper type information buffer in advance.
[0054]
When it is determined that the recording paper is the exclusive paper in the determination step of STEP5, the process proceeds to STEP6 and it is determined to record the black image data stored in the black image data buffer with the first black ink. Then, go to STEP9.
[0055]
If it is determined in STEP 5 that the recording sheet is plain paper, the process proceeds to STEP 7 to determine whether or not there is color image data in the color image data buffer.
[0056]
If it is determined in step 7 that there is color image data, the process proceeds to step 6 and it is decided to record the black image data stored in the black image data buffer with the first black ink. Then, go to STEP9.
[0057]
If it is determined in step 7 that there is no color image data, the process proceeds to step 8, and the black image data stored in the black image data buffer is changed to the first black ink and the second black image. After deciding to record using ink together, proceed to STEP 9.
[0058]
In STEP 9, the recording operation is performed by the recording head 101 using the black ink and the color ink determined in the above process.
[0059]
Although the embodiments of the recording apparatus and the embodiments of the recording method have been described above, the present invention is not limited to these. For example, the color ink to be used, the first black ink, and the second black ink are used. The composition is not limited to this. Furthermore, although the color inks used in the present embodiment are three colors of C, M, and Y, the color types are not limited to this, and a configuration in which light inks or the like are combined may be used.
[0060]
Further, the recording resolution is not limited to 360 dpi, and recording at a higher resolution is possible.
[0061]
Further, although the embodiment using an ink jet recording head of a type using a piezoelectric element has been described, the invention is not limited to this, and an ink jet recording head of a type using a heating element can also be used. Furthermore, the nozzle arrangement of the nozzle group is not limited to 1/180 inch pitch.
[0062]
【The invention's effect】
According to this embodiment, the special paper and the plain paper have the color ink having the water-soluble dye as the color material and the first black ink, and the second black ink having the pigment as the color material. A recording head having a first black nozzle group that discharges black ink, a second black nozzle group that discharges second black ink, and a color nozzle group that discharges color ink. A desired black image and color image, particularly, an ink jet recording apparatus configured to record the black image data by discriminating the paper type and simultaneously or selectively discharging the first black ink and the second black ink. In plain paper, it is possible to obtain a desired black image that is clear and has high water resistance and light resistance.
[0063]
Furthermore, a desired black image on plain paper can be recorded at a high speed by a configuration in which black image data is recorded by simultaneously ejecting the first black ink and the second black ink.
[Brief description of the drawings]
FIG. 1 is a schematic view of an ink jet recording apparatus of the present invention.
FIG. 2 is a block diagram showing components of the ink jet recording apparatus of the present invention.
FIG. 3 is a block diagram showing nozzle groups of a recording head 101 of the ink jet recording apparatus of the present invention.
FIG. 4 is a diagram illustrating one recording operation when recording is performed at a resolution of 360 dpi in the embodiment of the present invention.
FIG. 5 is a diagram illustrating another recording operation when recording is performed at a resolution of 360 dpi in the embodiment of the present invention.
FIG. 6 is a diagram showing one operation flow in the ink jet recording method of the present invention.
FIG. 7 is a diagram showing another operation flow in the ink jet recording method of the present invention.
[Explanation of symbols]
101 Recording head
102 Carriage
103 Carriage drive belt
104 Carriage drive motor
107 Recording paper
108 Transport roller
109 Guide shaft
201 Color separation means
202 Black image data storage means
203 Color image data storage means
204 Paper type information storage means
205 Black nozzle drive means
206 Color nozzle drive means
301 First black nozzle group
302 Second black nozzle group
303 Color nozzle group

Claims (3)

In an inkjet recording apparatus that uses a recording head having a plurality of nozzle groups and performs recording on recording paper by discharging ink from the plurality of nozzle groups moving in the main scanning direction.
The recording head is
A first black nozzle group for discharging a first black ink having a water-soluble dye as a coloring material;
A second black nozzle group for discharging a second black ink having a pigment as a coloring material;
Have
When forming a black image on the recording paper, if the recording paper is plain paper, the first black ink droplet and the second black ink droplet are adjacent to each other in the sub-scanning direction. An inkjet recording apparatus characterized by being driven onto a recording paper,
The recording head further includes a color nozzle group for discharging a color ink having a water-soluble dye as a coloring material,
The color nozzle group, the first black nozzle group, and the second black nozzle group are arranged in the recording head side by side in the main scanning direction,
The color nozzle group, the first black nozzle group, and the second black nozzle group each include a plurality of nozzles arranged at a predetermined pitch along the sub-scanning direction,
The second black nozzle group is arranged shifted in the sub-scanning direction with respect to the color nozzle group and the first black nozzle group,
When forming a color image on the recording paper,
The ink was ejected from the color nozzle group and the first black nozzle group, and ink droplets were ejected onto the recording paper at the pitch intervals in the sub-scanning direction, and the recording paper was transported and ejected at the intervals. Ink is ejected from the color nozzle group and the first black nozzle group between the ink droplets to drive the ink droplets onto the recording paper, thereby forming a color image with a predetermined resolution.
When a black image is formed on the recording paper, and the recording paper is plain paper,
Ink is ejected from the first black nozzle group and the second black nozzle group, and the ink droplets of the second black ink are ejected between the ink droplets of the first black ink, and the resolution of An ink jet recording apparatus that forms a black image. In an inkjet recording apparatus that uses a recording head having a plurality of nozzle groups and performs recording on recording paper by discharging ink from the plurality of nozzle groups moving in the main scanning direction.
The recording head is
A first black nozzle group for discharging a first black ink having a water-soluble dye as a coloring material;
A second black nozzle group for discharging a second black ink having a pigment as a coloring material;
Have
When forming a black image on the recording paper, if the recording paper is plain paper, the first black ink droplet and the second black ink droplet are adjacent to each other in the sub-scanning direction. An inkjet recording apparatus characterized by being driven onto a recording paper,
The recording head further includes a color nozzle group for discharging a color ink having a water-soluble dye as a coloring material,
The ink jet recording apparatus comprises:
Color separation means for separating the recording data into black image data and color image data;
Black image data storage means and color image data storage means for storing the separated recording data;
Paper type information storage means for storing paper type information of the recording paper;
A drive signal for discharging the first black ink and the second black ink from the first black nozzle group and the second black nozzle group simultaneously or selectively according to the paper type information is generated. Black nozzle driving means;
Color nozzle drive means for generating a drive signal for discharging the color ink from the color nozzle group;
An ink jet recording apparatus comprising:   The black nozzle drive means generates a drive signal for ejecting the first black ink from the first black nozzle group when the recording paper for forming the black image is a dedicated paper, and When the recording paper for forming an image is plain paper, the first black ink and the second black ink are simultaneously ejected from the first black nozzle group and the second black nozzle group. 3. The ink jet recording apparatus according to claim 2, wherein a drive signal is generated.

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