JP2011121315A - Ink jet recording method and ink jet recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink jet recording method providing excellent recording quality by using ink and treatment liquid, and improving the image fixing property just after recording, and reducing curling of a recording medium and irregularities of a recording surface. <P>SOLUTION: The ink for recording an image and the treatment liquid for improving recording characteristics of the ink are ejected onto the recording medium from a recording head based on image data. There are several kinds of treatment liquids (S1, S2, S3 and S4) ejected from the recording head, and the treatment liquid in accordance with an object attribute of the image to be recorded is selected from the several kinds of the treatment liquids. The selected treatment liquid is ejected to a contact position with the ink ejected onto the recording medium. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ink jet recording method and an ink jet recording apparatus that eject ink and treatment liquid onto a recording medium to form characters and images.

  Inkjet recording printers are widely used not only for personal use but also for commercial printing applications such as public notices, posters, and graphic prints, and therefore need to be compatible with various types of recording media. Examples of the recording suitability include image quality, recording quality, and image fastness. Image quality is evaluated by color development, homogeneity, sharpness of edges, bleeding, etc., and recording quality is evaluated by curling or irregularities on the recording surface caused by ink application. Scratch resistance, water resistance or weather resistance are used as evaluation factors.

  Here, bleeding refers to image unevenness at the boundary where different colors bleed from each other at the color boundary and become non-uniform. Scratch resistance means the stain resistance of an image caused by contact with a friction material (the back surface of another recording paper superimposed on the image, a line marker, etc.). Water resistance means the resistance of an image to general liquids that may come into contact with a recorded material, such as water, rain, or sweat from a person. The weather resistance means image discoloration resistance when exposed to air or light by long-term storage.

  In general, water-based inks for inkjet are roughly classified into dye inks using dyes as coloring materials and pigment inks using pigments. In addition to ingredients such as coloring materials, additives composed of water-based organic solvent solvents based on water, functional resins, surfactant additives, etc. are used for the purpose of preventing drying and clogging. There is an agent.

  Pigment inks have properties superior to dye inks in terms of image fastness such as water resistance and weather resistance. On the other hand, pigment inks are often inferior in terms of image quality such as color developability compared to dye inks, and the property that color developability is easily affected by the type of recording medium is also an issue. .

  As a technique for improving the image quality of pigment ink, Patent Document 1 discloses a two-component recording method using a combination of a color ink containing a salt and a black pigment ink that thickens or aggregates due to the action of the salt. Has been proposed. Patent Document 2 discloses a two-part recording method that improves color developability and bleeding by reacting a pigment ink containing a pigment and a resin emulsion with a treatment liquid containing a polyvalent metal salt. . This Patent Document 2 discloses a technique for improving image quality mainly of color developability by aggregating pigment ink on the surface of a recording medium such as plain paper where the color developability of the pigment ink is not good. Has been introduced.

Japanese Patent Laid-Open No. 06-106735 Japanese Patent Laid-Open No. 09-207424 JP 2004-209759 A

  In the two-component ink jet recording apparatus as described above, the treatment liquid and the ink that doubles as the treatment liquid are applied to the recording medium in addition to the image forming ink. The amount tends to be larger than when only ink is used. For this reason, in the two-component system, the ink fixing time is increased, the image is liable to be deteriorated or smeared due to contact with the recorded matter, and the curled recording material or the deflection (unevenness) of the recording surface is generated. There has been a problem that the recording article position is lowered and becomes noticeable.

  In particular, the recent recording operation of an ink jet recording apparatus has further increased in speed, and accordingly, image fixability immediately after recording has become extremely important. The main factor that hinders this image fixing is that water or an organic solvent contained in the ink remains in the ink. That is, immediately after recording, these solvent components remain in the ink dots and the ink is not sufficiently fixed, so that the image is easily disturbed or smeared by the contact of the friction material. In addition, since line marker drawing may be performed immediately after paper discharge, it is also required to improve image fixability in a few minutes after recording. That is, in line marker drawing, since the marker liquid is attached to the recorded image and rubbed against the pen tip, image disturbance such as tailing is very likely to occur immediately after recording. Such an inconvenience also occurs in the above-described reactive ink system. That is, since the aggregated pigment ink component is not sufficiently fixed on the surface of the recording medium, image smear due to contact with the marker pen occurs. Therefore, improvement of image fixability immediately after recording is one of the problems in the conventional two-component ink jet recording system.

  The present invention provides an ink jet recording method capable of obtaining excellent recording quality using ink and a treatment liquid, improving image fixability immediately after recording, and reducing curling of a recording medium and unevenness of a recording surface, and An object is to provide an ink jet recording apparatus.

  In order to achieve the above object, the present invention has the following configuration.

That is, in the first aspect of the present invention, the ink for recording an image and the treatment liquid for improving the recording characteristics of the ink are ejected from the recording head onto the recording medium based on the image data, An ink jet recording method in which ink and the processing liquid are brought into contact with each other on the recording medium, wherein the recording head is capable of discharging a plurality of types of processing liquids,
Selecting a treatment liquid according to an object attribute of an image to be recorded from the plurality of types of treatment liquids, and causing the selected treatment liquid to be ejected to a contact position with ink ejected onto the recording medium; To do.

According to a second aspect of the present invention, an ink for recording an image and a treatment liquid for improving the recording characteristics of the ink are ejected from a recording head onto a recording medium based on the image data. An ink jet recording apparatus in which ink and the processing liquid are brought into contact with each other on the recording medium, wherein the recording head is configured to be capable of discharging a plurality of types of processing liquid,
The selecting means for selecting a processing liquid according to the object attribute of the image to be recorded from the plurality of types of processing liquids, and discharging the selected processing liquid to a contact position with the ink discharged on the recording medium And a control means for controlling the ejection operation of the recording head.

  According to the present invention, it is possible to obtain excellent recording quality by using ink and processing liquid, image robustness such as improvement of image fixability immediately after recording, and curling of recording media and unevenness of recording surfaces. It is possible to improve the recording article quality, such as the reduction of generation.

FIG. 3 is a conceptual diagram schematically illustrating a state in which a treatment liquid and pigment ink are in contact with each other on a recording medium and ink dots are fixed. 1 is a perspective view illustrating a main part of an ink jet recording apparatus according to an embodiment of the present invention. FIG. 4 is a schematic view of the recording head as viewed from the discharge port side. FIG. 2 is a block diagram illustrating a schematic configuration of a control system provided in the ink jet recording apparatus according to the embodiment. It is explanatory drawing which shows the structure of the image process part in this embodiment. It is a flowchart which shows the production | generation procedure of the binary recording data of the process liquid implemented in this embodiment. It is a schematic diagram of the image for evaluation in this embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

The ink jet recording method in the present embodiment is a recording method using a so-called two-liquid type ink jet recording apparatus that forms an image with a processing liquid and ink. Here, the treatment liquid in the present invention refers to a liquid ejected to a recording medium in order to improve the recording suitability such as the image quality, the recording article quality, and the image fastness described above.
In this embodiment, a plurality of types of processing liquids that improve the recording characteristics of ink are used, and a processing liquid is selected from the processing liquids according to the object attributes of the image constituting the input image data, and the selected processing is performed. The liquid is ejected to a contact position with the ink ejected onto the recording medium. Here, the object attribute of an image represents the type of image data of an image to be recorded, and represents a thin line object such as a character or a line and an image object such as a photograph or a graphic.

  The treatment liquid in the present embodiment has a property of agglomerating or thickening (gelling) ink by contact with the ink on the recording medium in order to improve recording suitability. In the following, the effect of using different processing liquids according to the object attributes of the image in the two-liquid type ink jet recording apparatus will be described.

  FIG. 1 is a conceptual diagram schematically showing a state in which a treatment liquid and pigment ink are in contact with each other on a recording medium and ink dots are fixed. Here, the treatment liquid 101 includes a reaction component 114 that reacts with ink, and water and a solvent component 103a. In addition, the ink contains pigment particles 111 of color material, water, and a solvent 103b.

FIG. 1A shows a state in which the treatment liquid 101 has been deposited on the upper surface of the recording medium 100. At this stage, the pigment ink 102 has not been deposited on the treatment liquid, and the ink has not been deposited on the treatment liquid. Represents the state before touching.
FIG. 1B shows a state immediately after the processing liquid 101 and the pigment ink 102 are in contact with each other on the upper surface of the recording medium. The processing liquid is applied by applying the pigment ink to the recording medium to which the processing liquid has been applied in advance. Shows the moment of contact. Note that at the moment when the processing liquid and the ink come into contact with each other, the reactive component 114 contained in the processing liquid induces dispersion breakage in the pigment ink, resulting in the generation of coarse particles 111b in which the color material is aggregated.
FIG. 1C shows a state in which the coarse particles 111b are fixed near the surface layer of the recording medium 111c, and at the same time, the solvent component 103c contained in the treatment liquid and the pigment ink is solid-liquid separated and penetrates into the recording medium. Show.

  As shown in FIG. 1, the ink droplets after landing on the recording medium are in a state where water and solvent components applied from the treatment liquid and the ink remain. The water and solvent components are absorbed into the recording medium and evaporated into the air, whereby ink dot fixing (image fixing) proceeds. As the fixing speed of the ink dots becomes slower, the image smear due to marker pulling immediately after recording becomes more prominent.

  Since the treatment liquid contains a large amount of water and solvent components as in the case of the ink, the ink fixing speed varies depending on the material components constituting the treatment liquid. In the present embodiment, as a result of intensive studies on the fixing speed of the ink depending on the amount of water in the processing liquid and the solvent type, the fixing speed increases as the amount of water contained in the processing liquid increases. We found a tendency to improve. In addition, it was confirmed that the solvent component contained in the processing solution has a lower fixing speed as the aqueous solvent having a higher boiling point is used.

  Next, the principle of occurrence of curling of a recorded matter and unevenness of a recording surface due to recording of water-based ink on a recording medium will be described by taking, as an example, plain paper often used as an inkjet recording medium. Generally, plain paper has a pulp fiber, which is the main component of paper, exposed on the paper surface. The ejected ink droplets are deposited on the pulp fiber, and water and solvent components in the ink are directly absorbed into the pulp fiber. The pulp fiber absorbs water and expands, and then the absorbed moisture evaporates and the pulp fiber contracts. On the surface opposite to the surface on which the image is recorded, the amount of moisture absorption is different and the amount of expansion / contraction is different, so that paper curls and recording surface irregularities occur. Here, the curl of the paper and the size of the irregularities on the recording surface are greatly affected by the amount of moisture applied, and the curl and the irregularities on the recording surface increase as the amount of moisture increases. Therefore, the unevenness of the recording surface increases in an image area such as a photograph or graphic that records a large amount of ink, and the curl increases as the image area that occupies the entire paper increases. Further, when the ink recording amount is the same, the curl and the unevenness of the recording surface increase as the amount of water contained in the ink increases.

  As described above, since the processing liquid contains water and a solvent component, in the two-liquid type ink jet recording method, the curl and the unevenness of the recording surface increase as the amount of water in the processing liquid increases. In addition, curling and unevenness of the recording surface can be efficiently suppressed by reducing the amount of water in the processing liquid by using an aqueous solvent having a curling suppression effect contained in specific material components of the processing liquid described later. Is possible.

  In view of the above, in the two-liquid type ink jet recording method according to the present embodiment, different types of processing liquids are used in order to simultaneously improve the image fixability immediately after recording and the recording article position such as curling and unevenness of the recording surface. Is used. In other words, for text and lines where high marker resistance is required, images are recorded using a processing liquid with a high water content, and for image areas where high curl resistance is required, the water content Use a processing solution with a small amount.

  Next, an ink jet recording apparatus capable of realizing the above ink jet recording method will be described. In the ink jet recording apparatus according to the present embodiment, four types of pigment inks of black, cyan, magenta, and yellow are ejected as inks, and two types of treatment liquids having different properties as treatment liquids that react with the inks. A case will be described as an example.

(Overall configuration of inkjet recording apparatus)
FIG. 2 is a perspective view showing a main part of the ink jet recording apparatus. The ink jet recording apparatus includes a carriage 11 that detachably mounts a recording head 21 in which recording heads for inks of various colors are integrated. The carriage 11 optically reads the carriage motor 12 that reciprocates in the main scanning direction (X direction) along the guide shaft 6, the belt 5 a that transmits the driving force of the carriage motor 12 to the carriage 11, and the position of the carriage 11. And an encoder sensor 13.

  The recording head 21 includes an ink discharge portion 21In that can discharge a plurality of colors of ink and a processing liquid discharge portion 21S that can discharge a plurality of types of processing liquids. In each of the ejection portions 21In and 21S, nozzle openings (ejection ports) 23 for ejecting ink and processing liquid are arranged as shown in FIG. The recording of the image on the recording medium is performed by discharging the ink or the processing liquid. The arrangement of the discharge ports 23 will be described later with reference to FIG.

  The ink discharged from each discharge portion of the recording head 21 and each processing liquid are stored in an ink tank (not shown) provided for each type, and they correspond to each ink and processing liquid in the recording head 21. It is supplied to the liquid chamber provided through the supply tube 25. Note that the ink or the processing liquid supplied into the liquid chamber is discharged from a discharge port located at an end portion thereof through a nozzle constituting the liquid path.

  In addition, the inkjet recording apparatus is provided with a recovery device 141 in order to maintain the ejection performance of the recording head. The recovery device 141 includes a cap (not shown) that can cover the ejection port surface on which the ejection port of the recording head is formed, a blade 143 that wipes ink adhering to the ejection port surface, and the like. The carriage 11 returns to the home position where the cap 141 is provided and waits when recording is not performed, and the cap covers the discharge port surface.

Next, the configuration of the recording head used in this embodiment will be described.
FIG. 3A is a view of the recording head 21 as viewed from the ejection port side. The recording head 22 has a plurality of ejection port arrays arranged along the main scanning direction (X direction). Each ejection port array is provided corresponding to the number of inks used and the type of processing liquid. In the present embodiment, the ejection port portion 21In that ejects ink is provided with four ejection port arrays 21K, 21C, 21M, and 21Y corresponding to black ink, cyan ink, magenta ink, and yellow ink, respectively. . In addition, as the treatment liquid ejection section 21S that ejects the treatment liquid, two rows of treatment liquid nozzle arrays 21S1, 21S2, 21S3, and 21S4 are arranged in parallel, two on each side of the ink ejection section 21In in the main scanning direction. It is installed. Different types of treatment liquids (S1, S2, S3, S4) are supplied to the four rows of treatment liquid nozzles.

  In each ejection port array, 1280 ejection ports 23 are arranged along the Y direction at intervals corresponding to a recording density of 1200 dpi. In the nozzle, there are provided an electrothermal conversion element (heating element) (not shown) that generates thermal energy as an ink discharge means for discharging the supplied ink, and an electrode wiring (not shown) for supplying electric power thereto. It has been. These heating elements and electrode wirings are formed on a substrate made of silicon or the like by a film forming technique. The amount of ink discharged from each discharge port 23 is about 4 ng. Here, an example in which an electrothermal conversion element is used as the ink ejection unit has been described, but the present invention is not limited to this. For example, a piezoelectric element that is an electromechanical conversion element may be used. Other means may be used, and all ink discharge means capable of performing ink jet recording can be used.

  An example of the recording operation of the ink jet recording apparatus will be described with reference to FIG. The recording medium 1 is supplied to the recording operation area one by one by a paper feed roller (not shown). In the recording operation area, the recording medium 1 is conveyed between the recording head 21 and a platen (not shown) by a pair of conveying rollers. On the other hand, the recording head 21 performs recording on the recording medium 1 according to the output image data while moving in the X direction (main scanning direction) in FIG. This recording is performed by applying the processing liquid and ink droplets on the recording medium in the order of the processing liquid, black ink, cyan ink, magenta ink, and yellow ink. When the recording for one scan is completed, the recording head 21 returns to the home position in the case of one-way recording, and the recording head 21 is moved again in the X1 direction, so that the processing liquid, black ink, cyan ink, magenta ink, yellow. Recording is performed by discharging the ink onto the recording medium in the order of ink.

  Before one recording operation (one scan) in one direction is completed and before the next recording operation is started, the conveyance roller pair is driven to move the recording medium by a predetermined amount in the Y direction (sub-scanning direction). Be transported. By repeating the recording operation for one scan and the conveying operation for a predetermined amount as described above, recording is performed on the recording medium by a predetermined width.

  In this embodiment, a one-way recording mode in which the application order of ink and processing liquid is always constant and a bidirectional recording mode in which the application order of ink and processing liquid is reversed every scan can be executed. The effects described below can be obtained.

  Further, the treatment liquid used in the present embodiment ejects the treatment liquid onto the recording medium prior to the ink in order to more effectively use the treatment liquid that contacts the pigment ink and aggregates the pigment on the recording medium. It is desirable to make it. Accordingly, as shown in FIG. 3B, a recording head in which the processing liquid nozzle rows 21S1, 21S2 and the ink nozzle rows 21K, 21G, 21M, 21Y are arranged to be shifted in the sub-scanning direction may be used. good. According to this, in either one-way recording or two-way recording, it becomes possible to always apply the treatment liquid to the recording medium prior to the ink. Further, in the recording head shown in FIG. 3A, when only two types of processing liquids are used, the same two types of processing liquids may be supplied to one and the other of the ink discharge portions. . According to this, similarly to the recording head shown in FIG. 3A, the treatment liquid can be applied prior to the ink in either one-way recording or two-way recording.

(Outline of control system)
4 is a block diagram showing a schematic configuration of a control system circuit of the ink jet recording apparatus shown in FIG. In FIG. 4, reference numeral 300 denotes a recording control unit that controls a recording operation, and an image input unit 302 is connected to the recording control unit 300 via an interface 303. The image input unit 302 transfers image information to be recorded to the recording control unit 300, and includes a host computer (host PC) or an image reader.

  The interface 303 inputs a recording signal from the image input unit 302 and a control signal related to recording to the recording control unit 300. The recording control unit 300 includes an MPU (Micro Processing Unit) 306, a ROM (Read Only Memory) 307, a gate array 304, a DRAM (Dynamic Random Access Memory) 305, and the like. The MPU 401 executes various processes such as calculation, determination, and control in accordance with a control program stored in the ROM, and has functions as a selection unit and a control unit of the present invention. The gate array 304 controls supply of recording data to the recording head 22 and also controls data transfer between the interface 400, MPU 401, and DRAM 403. The DRAM 305 is a dynamic RAM that stores a recording signal supplied to the recording head 22, a control signal for recording, and various data such as the number of recording dots and the number of replacements of the recording head.

  The recording control unit 300, through various drivers 307, 308, and 309, ejects the recording head, carriage operation for driving the recording head 22 in the main scanning direction, and conveying operation for conveying the recording medium in the sub-scanning direction, etc. To control.

(Recording data generation process)
Next, recording data generation processing executed in the above configuration will be described.
In the present embodiment, the type of processing liquid to be used is selected based on object information such as characters, lines, and images. In the ink jet recording apparatus, it is possible to improve both the fixability of the image immediately after recording and the recording article position.

  FIG. 5 is a block diagram showing a data conversion process for converting the input image data 1011 into print data that can be printed by the ink jet printing apparatus. Each process described in the recording apparatus 1100 illustrated in FIG. 5 is executed by the recording control unit 300 illustrated in FIG. The host PC corresponds to the image input unit 302 in FIG. 4 and exchanges data with the recording apparatus 1100 via the interface 303.

  In the host PC 1010, first, rendering processing 1012 is performed with a resolution of 600 dpi on input RGB data (input image data) 1011 received from an application. As a result, multi-value (256 values in this embodiment) multi-value recording RGB data 1013 is generated.

  On the other hand, based on the input image data 1011, discrimination processing 1014 for character / line objects and image (bitmap data, etc.) objects, which are a plurality of types of image components included in the image to be recorded, is performed. Subsequently, rendering processing is performed on the character / line object data to generate binary character / line object data 1015 (data obtained by combining the character and line object data) with a resolution of 600 dpi, and is transferred to the recording apparatus. The

  In the recording apparatus 1100, after correcting the recording multi-value RGB data 1101 by luminance density conversion and color processing, a multi-color corresponding to each color ink (black, cyan, magenta, yellow ink) used in the recording apparatus. A color conversion process 1101 to value data is performed.

  The converted multi-value data of each color is subjected to a quantization process 1102 for quantizing it into N-value gradation values by a predetermined quantization method. As a quantization method, general multi-level error diffusion processing or the like can be used. For example, when the input resolution is 600 dpi and the output resolution is 1200 dpi, the output data dots are 2 × 2 4 dots per block for the input image data of 8 bits per pixel. The number of gradations that can be expressed by one block is five. Accordingly, the quantization process outputs quantized values quantized into five values of “0”, “64”, “128”, “192”, and “255”. Each quantized value corresponds to the gradation values “0”, “1”, “2”, “3”, “4”. In the present embodiment, the data is quantized into quinary data with a resolution of 600 dpi by the error diffusion method.

  Each quantized five-value color data is index-expanded into 1200 dpi binary data 1104 that can be recorded by each recording head by an index expansion process 1012. In this index expansion process 1013, dot arrangement data in a matrix form is used corresponding to each value of the quinary data of each color, and a dot arrangement pattern is output according to the value of the quinary data. In the present embodiment, the quinary data is expanded into a 2 × 2 dot matrix.

  Based on the binary data 1104 of each color and the binary character / line object data 1015, in the processing liquid data generation processing 1105 described below, in this embodiment, binary data 1106 corresponding to two types of processing liquid is generated. To do. Based on these binary data, a record data generation process 1107 is performed.

  FIG. 6 is a flowchart showing the processing procedure of the processing liquid data generation processing 1105. By the data synthesizing process, a logical sum process is performed on the binary recording data 1104 of each color ink (step 1201). As a result, binary intermediate data indicating the ink recording area is generated, and primary data corresponding to the processing liquid recording area is obtained. In step 1202, bold processing for expanding a predetermined amount of data area is performed on the intermediate data generated in step 1201. Similar bold processing is also performed on binary character / line object data 1015 processed in advance in the host PC 1010. In an actual recording operation, a deviation occurs between the ink landing position and the treatment liquid landing position, and when the deviation amount increases, the effect of the processing liquid does not appear and image unevenness or streaks may occur. . It is possible to mitigate the influence of such landing position deviation by bold processing.

  Data division processing is performed on the intermediate data indicating the ink recording area subjected to bold processing based on the character / line object data subjected to bold processing (step 1203). In this data division process, a division process for generating intermediate data ms1 and ms2 corresponding to each of a plurality of treatment liquids (two kinds of treatment liquids in the present embodiment) is performed. In the present embodiment, the processing liquid to be used is changed between the area corresponding to the character / line object image and the area corresponding to the image image. For this reason, in the character / line area, a logical product means of binary intermediate data indicating the ink recording area (primary data corresponding to the processing liquid recording area) and binary character / line object data 1015 is used. The processing solution data ms1 to be used can be obtained. Further, processing liquid data ms2 used in other areas is generated by logical difference processing between the intermediate data and the processing liquid data ms1. The processing solution data ms1 and ms2 are subjected to a predetermined thinning process (step 1204), thereby generating binary recording data 1106 for each processing solution. Here, the thinning pattern is a pattern for reducing the number of dots storing the processing liquid at a predetermined rate. Further, the amount of the treatment liquid applied to the recording medium may be changed according to the type of the image object, and this can be realized by changing the type of the thinning pattern.

  In the above-described embodiment, the amount of treatment liquid applied to the recording medium may be changed for each type of ink, which is effective when the effect when contacting with the treatment liquid differs depending on the type of ink. is there. In this process, it is possible to change the application amount of the processing liquid to the recording medium according to the ink type by performing a thinning process for each ink on the binary recording data of each color ink.

  In the above-described embodiment, the case where two types of processing liquids are used has been described as an example. However, in the present invention, three or more types of processing liquids (four types of processing liquids in FIG. 2) are used according to the object attribute of the image. It is also possible to use S1-S4) properly. For example, in the recording head shown in FIG. 3A, different processing liquids are supplied to the nozzle arrays 21S1 to 21S4 for processing liquid, and recording conditions such as image object attributes, recording medium types, and ink types are recorded. Alternatively, a treatment liquid suitable for the above may be selectively discharged.

  Furthermore, in the above description, the case where an area for recording an image and an area for recording characters / lines are mixed in the image to be recorded has been described as an example. However, according to the embodiment having the above-described configuration, even when an image to be recorded is composed of only one of an image image and a character / line image, an appropriate processing liquid can be selected and discharged according to the object of each image. It goes without saying that it is done.

  In the above embodiment, image data processing is allocated to the host PC 1010 and the recording device 1210. However, the present invention is not limited to this configuration. For example, the recording device 1210 may execute all of the processes shown in FIG.

  In the above-described embodiment, the binary output data of the processing liquid is generated by performing the data processing on the binary output image data of each color. However, the processing liquid is generated based on the multi-value data of each color ink. It is also possible to generate binary output data. Further, the method for generating the binary recording data of the treatment liquid can be performed by combining these methods, and is not limited to the above, and can be selected as appropriate.

  Hereinafter, the configuration of the treatment liquid and ink used in the above embodiment will be described.

(Processing liquid)
A specific configuration of the processing liquid used in this embodiment is shown below. In the following description, “part” or “%” is based on mass unless otherwise specified.
The treatment liquid in the present embodiment has a function of aggregating or thickening the ink by contact between the ink and the treatment liquid on the recording medium in order to improve the recording quality.
The treatment liquid is composed of a reaction component for aggregating or thickening the ink when it comes into contact with the ink, and a solvent component.

  As reaction components, polyvalent metal salts such as magnesium, calcium, barium, iron (II), copper (II), zinc, iron (III) and aluminum can be used. Furthermore, as the reaction component, an acid buffer or an alkaline buffer that induces a pH shock at the time of contact with the ink, a resin having a charge opposite to that of the component in the ink, or the like can be used. For example, when an anionic pigment ink is used as the ink, the polydisperse metal salt as the reaction component can induce dispersion breakage of the ink upon contact with the ink.

  As the solvent component, additives such as water, an organic solvent, and a surfactant are used. As the organic solvent, a material having excellent solubility in water and a high boiling point is suitable. Alcohol solvents, polyhydric alcohol solvents such as glycerin, ether solvents and the like can be used.

  In addition, in order to suppress curling and unevenness of the recorded material, a material having a curl suppressing function (curl inhibitor) such as polyethylene glycol, polypropylene glycol, trimethylolpropane, saccharides, sugar alcohols, or the like is used as a solvent component. Is preferred. As the solvent component having the curl suppressing function, a known material described in Patent Document 3 can be used.

  Two types of treatment liquids used in the present embodiment can be prepared by adjusting the content of the organic solvent. In the processing liquid used in the image area of the character / line object, the content of the organic solvent is lowered and the processing liquid S1 having a high water content is used. Further, in the processing liquid used in the image area of the image object, the processing liquid S2 having a high content of the curl suppression solvent is used.

Here, an example of a material configuration of the processing liquid S1 and the processing liquid S2 is shown below.
[Preparation of treatment liquid S1]
・ Calcium nitrate tetrahydrate 10.0 parts ・ Diethylene glycol 10.0 parts ・ Acetylenol EH (manufactured by Kawaken Fine Chemicals) 0.2 part ・ Ion-exchanged water 79.8 parts

  After mixing and dissolving the above components, pressure filtration was further performed with a membrane filter (manufactured by MILLIPORE) having a pore size of 1.2 μm to obtain a reaction solution S1. The surface tension of the obtained reaction liquid was 36 mN / m.

[Preparation of treatment liquid S2]
・ 10.0 parts of calcium nitrate tetrahydrate ・ 30.0 parts of trimethylolpropane ・ 0.2 parts of acetylenol EH (manufactured by Kawaken Fine Chemical Co., Ltd.) ・ balance of ion-exchanged water

  After mixing and dissolving the above components, pressure filtration was further performed with a membrane filter (manufactured by MILLIPORE) having a pore size of 1.2 μm to obtain a reaction solution S2. The surface tension of the obtained reaction solution was 38 mN / m.

(Ink configuration)
A specific configuration example of the ink in the present embodiment is shown below.

[Preparation of black ink]
[Synthesis Example 1 (Preparation of Black Pigment Dispersion)]
-Random copolymer consisting of styrene-acrylic acid-ethyl acrylate (acid value 200, weight average molecular weight 9,000) 1.4 parts-1.0 part monoethanolamine-5.0 parts diethylene glycol-81 parts ion-exchanged water .6 parts

The above components are mixed and heated to 70 ° C. in a water bath to dissolve the resin component. To this solution, 10 parts of carbon black (FW18, manufactured by Degussa) and 1 part of isopropyl alcohol were added, premixed for 30 minutes, and then dispersed under the following conditions.
・ Disperser: Sand grinder (manufactured by Igarashi Machine) ・ Crushing media: Zirconium beads, 1 mm diameter ・ Filling rate of grinding media: 50% (volume ratio)
・ Crushing time: 3 hours

  After the above dispersion treatment, further centrifugal separation treatment (12,000 rpm, 20 minutes) was carried out to remove coarse particles to prepare a black (K) pigment dispersion.

[Adjustment Example 1 (black ink adjustment)]
Using the black pigment dispersion obtained by the above treatment, an ink containing a pigment was produced according to the following composition ratio to obtain pigment ink K1. The surface tension of the obtained pigment ink was 38 mN / m.
-Pigment dispersion liquid of Synthesis Example 1-10.0 parts of glycerin-5.0 parts of ethylene glycol-1.0 part of acetylenol EH (manufactured by Kawaken Fine Chemicals)-54.0 parts of ion-exchanged water

[Production of cyan ink]
As a pigment, C.I. I. A cyan pigment dispersion was obtained in the same manner as in Synthesis Example 1 except that CI Pigment Blue 15: 3 was used. Using the cyan pigment dispersion obtained here, a cyan ink was prepared according to the same formulation as in Preparation Example 1. The obtained pigment ink had a surface tension of 37 mN / m.

[Production of magenta ink]
As a pigment, C.I. I. A magenta pigment dispersion was obtained in the same manner as in Synthesis Example 1 except that CI Pigment Red 7 was used. Using the magenta pigment dispersion obtained here, magenta ink was prepared according to the same formulation as in Preparation Example 1. The surface tension of the obtained pigment ink was 36 mN / m.

[Preparation of yellow ink]
As a pigment, C.I. I. A yellow pigment dispersion was obtained in the same manner as in Synthesis Example 1 except that CI Pigment Yellow 74 was used. Using the yellow pigment dispersion obtained here, a yellow ink was prepared according to the same formulation as in Preparation Example 1. The obtained pigment ink had a surface tension of 37 mN / m.

(Production and evaluation of recorded material)
Using the above treatment liquid and ink, a recorded matter was produced by the recording method described above, and the effect was verified. As shown in the schematic diagram of FIG. 7, the recorded image was input image data that was an evaluation image consisting of 10-point black characters in the upper half of A4 and a solid image in the lower half. Black characters were formed with black ink, and the recording duty was 100%. The recording duty of process black was set to 100%, and recording was performed by equally dividing cyan, magenta, and yellow. For the character portion, the treatment liquid S1 was used, and its recording duty was 30%. The treatment liquid S2 was used for the solid area, and the recording duty was 50%. The 100% recording duty referred to here corresponds to a state in which four ink dots are recorded at a resolution of 1,200 dpi for an image unit area of 600 dpi. The recording was performed so that the recording order of the treatment liquid and the ink in the same pass was the order of the treatment liquid and the ink.

  The recorded matter obtained as described above was subjected to a marker pulling test immediately after recording and a curling test by standing. In the marker drawing test, a marker was drawn manually by a human hand on a character portion that had passed 5 minutes after recording with a yellow line marker, and the dirty state of the character was subjectively evaluated. The curl test was evaluated by observing the floating state of the recording medium one day after leaving the recorded matter in an environment of a temperature of 25 ° C. and a humidity of 50%. For comparison with the recorded matter obtained by the above recording based on the present embodiment, an image is recorded with only the processing liquid S1 or the processing liquid S2 without changing the type of the processing liquid between the character portion and the image image area. Similar evaluations were made. As a result, as shown in Table 1, compared with the recorded material B or C in which an image is recorded with only one type of processing liquid, the recorded material A in which the type of processing liquid is properly used according to the image area is resistant to marker and resistance. Both the curl properties could be improved.

[Evaluation criteria for marker resistance]
○: Image is distorted, but characters can be distinguished.

    Δ: Characters cannot be accurately identified due to image distortion.

[Evaluation criteria for curl resistance]
○: The maximum floating height of the recorded material is 3 cm or less.

    Δ: The maximum floating height of the recorded material is 5 cm or more.

DESCRIPTION OF SYMBOLS 1 Recording medium 21 Recording head 21In Ink ejection part 21S Processing liquid ejection part 23 Ejection port 101 Processing liquid 102 Ink 111 Pigment particle 300 Recording control part 305 RAM
306 MPU
307 ROM
310 Image Processing Unit 1014 Object Discrimination Processing 1105 Processing Liquid Data Generation Processing 1107 Recording Data Generation Processing 1100 Recording Device S1, S2 Processing Liquid

Claims (9)

An ink for recording an image and a processing liquid for improving the recording characteristics of the ink are ejected from a recording head onto a recording medium based on the image data, and the ink and the processing liquid are discharged onto the recording medium. An ink jet recording method for contacting with
The recording head can discharge a plurality of types of processing liquids,
Selecting a treatment liquid according to an object attribute of an image to be recorded from the plurality of types of treatment liquids, and causing the selected treatment liquid to be ejected to a contact position with ink ejected onto the recording medium; Inkjet recording method.   The inkjet recording method according to claim 1, wherein an image region having different object attributes is included in the image to be recorded, and a processing liquid corresponding to the object attribute of each image region is selected.   3. The ink jet recording method according to claim 1, wherein different types of processing liquid are selected depending on whether the object attribute of the image to be recorded is an image or a character or a line.   The plurality of types of treatment liquids are a plurality of treatment liquids having different curl suppression effects of recorded matter, and when the object attribute is an image image, use a treatment liquid having a high curl suppression effect for the image, 4. The ink jet recording method according to claim 1, wherein when the object attribute is a character or a line, a processing liquid having a low curl suppression effect is used for the image.   The ink jet recording method according to any one of claims 1 to 4, wherein the curl suppressing effect of the treatment liquid is adjusted by a content of the curling inhibitor.   The ink jet recording method according to claim 1, wherein an amount of the treatment liquid applied per unit area in the recording medium is changed according to the object attribute.   The contact between the ink and the treatment liquid on the recording medium is performed by performing the step (A) of ejecting the treatment liquid onto the recording medium and the step (B) of ejecting the ink onto the recording medium, The inkjet recording method according to claim 1, wherein the step (A) is performed prior to the step (B).   8. The treatment liquid according to claim 1, wherein the treatment liquid has a property of aggregating or gelling the ink when it comes into contact with the ink on the recording medium. Inkjet recording method. An ink for recording an image and a processing liquid for improving the recording characteristics of the ink are ejected from a recording head onto a recording medium based on the image data, and the ink and the processing liquid are discharged onto the recording medium. An ink jet recording apparatus that is brought into contact with
The recording head is configured to be capable of discharging a plurality of types of processing liquids,
A selecting means for selecting a processing liquid according to the object attribute of the image to be recorded from the plurality of types of processing liquid;
An ink jet recording apparatus comprising: a control unit that controls an ejection operation of the recording head so that the selected processing liquid is ejected to a contact position with the ink ejected onto the recording medium.

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