JP2008132670A - Inkjet recording method and inkjet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sufficient amount of reaction liquid necessary for improving image quality by determining the amount of reaction liquid according to the amount of ink discharged when recording is performed using ink nozzles having large and small nozzle configurations.
The amount of reaction liquid is varied according to the amount of ink discharged. As means for making the amount of the reaction liquid different, there are a method of changing the thinning rate and a method of changing the discharge amount of the reaction liquid according to the ink discharge amount.
[Selection] Figure 4

Description

  The present invention relates to an ink jet recording method, and more particularly to an ink jet recording method in which a reaction liquid having a component that insolubilizes or agglomerates a colorant in an ink is applied over the ink.

  The ink jet recording method performs recording by ejecting ink droplets and attaching them to a recording medium such as recording paper. In particular, as described in Patent Literature 1, Patent Literature 2, and Patent Literature 3, an electrothermal conversion element is used as an ejection energy generation element, and the thermal energy is applied to the ink to generate bubbles, thereby generating ink droplets. The ejection method can easily realize a high-density multi-orifice of the recording head and can record a high-resolution, high-quality image at high speed.

  However, inks used in conventional ink jet recording methods such as those described in the above documents generally contain water as a main component and contain a water-soluble high-boiling solvent such as glycol for the purpose of preventing drying and clogging. It is a thing. When recording on plain paper using such an ink, the ink penetrates into the inside of the recording paper and a sufficient image density cannot be obtained, or the recording paper surface filler and sizing agent are unevenly distributed. The image density is considered to be non-uniform. In particular, when trying to obtain a color image, the inks of a plurality of colors are applied one after another before fixing, so that the color is blurred at the boundary portion of the different color image and mixed unevenly (hereinafter referred to as “color image”). , And bleeding) may cause deterioration of recording quality.

  On the other hand, for the purpose of improving image density and reducing bleeding, a method of applying a liquid (also referred to as a reaction liquid in this specification) that insolubilizes an ink coloring material such as a dye or pigment prior to ink application. It has been known. For example, Patent Document 4 proposes prevention of bleeding by utilizing a reaction between a polyvalent metal ion and a carboxyl group, and Patent Document 5 discloses bleeding by a reaction between a pigment, a resin emulsion, and a polyvalent metal salt. There are proposals to improve this.

  Further, in Patent Document 6, the position of an image to be recorded is recognized in advance, and a reaction liquid that insolubilizes recording ink and its coloring material such as a dye is used, and discharge data of the reaction liquid is obtained based on the discharge data of the recording ink. Discloses an ink jet recording method in which a recording ink and a reaction liquid are overlapped for recording. Specifically, the reaction liquid is drawn prior to the recording ink, the reaction liquid is overlaid on the previously drawn recording ink, the recording ink is overlaid on the previously drawn reaction liquid, and further the reaction liquid is overlaid. A method of drawing is disclosed.

By the way, the color ink jet recording apparatus usually uses four types of inks of black (K), cyan (C), magenta (M), and yellow (Y). Devices that use inks of different colors and different ejection amounts are also being provided.
Japanese Patent Publication No. 61-59911 Japanese Patent Publication No. 61-59912 Japanese Examined Patent Publication No. 61-59914 JP-A-5-202328 JP-A-9-207424 JP 58-128862 A

  Here, when generating the reaction liquid discharge data to be applied to the ink, if the reaction liquid discharge data is generated at the same ratio for a plurality of inks having different discharge amounts, the ink with a larger discharge amount is generated. As a result, the reaction liquid becomes excessive for ink with a small amount of reaction liquid and a smaller discharge amount.

  Conventionally, since the amount of the reaction liquid applied onto the recording medium is constant regardless of the ink discharge amount, the excess or deficiency of the reaction liquid applied onto the recording material medium occurs as described above. There was a problem that. For this reason, when the reaction solution is insufficient, insolubilization of the colorant becomes insufficient, the image quality is deteriorated, and when the reaction solution becomes excessive, the running cost increases due to an increase in the amount of the reaction solution used or the solidity is uniform. There arises a problem that the performance is lowered.

  The present invention has been made to solve the above-described problems, and the object of the present invention is to provide each of the recording media to be recorded when recording is performed using inks with different ink discharge amounts. It is an object of the present invention to provide an ink jet recording method and an ink jet recording apparatus capable of applying a sufficient amount of reaction liquid necessary for improving image quality by determining the discharge amount of the reaction liquid according to the ink discharge amount.

  Therefore, in the present invention, a recording head that discharges a plurality of discharge amounts of ink and a recording head that discharges a reaction liquid containing a component that insolubilizes or aggregates the colorant in the ink are used. In the ink jet recording method in which recording is performed by applying the reaction liquid, the discharge amount of the reaction liquid is varied according to the discharge amount of the ink discharged from the recording head.

  In addition, the amount of the reaction liquid with respect to the ink with a larger discharge amount is set to be larger than the amount of the reaction liquid with respect to the ink with a smaller discharge amount.

  In addition, as a recording head for discharging the reaction liquid, a recording head capable of changing the discharge amount of the reaction liquid at one time is used. For the ink with a smaller discharge amount, the discharge with a smaller reaction liquid discharge amount is performed.

  Further, as a recording head for discharging the reaction liquid, a plurality of recording heads with different reaction liquid discharge amounts are used, and for a larger discharge amount, a recording head with a higher reaction liquid discharge amount is used. For ink with a smaller ejection amount, a recording head with a smaller reaction liquid ejection amount is used.

  In addition, the discharge data of the reaction liquid is generated by performing a thinning process using a mask on the discharge data of the ink for discharging the ink, and the discharge amount is increased by changing the mask in the generation. The amount of the reaction liquid for the ink is different from the amount of the reaction liquid for the ink with a smaller discharge amount.

  In addition, the recording ratio of the reaction liquid generated by the thinning with the mask corresponding to the ink with the larger ejection amount is higher than the recording ratio of the reaction liquid generated with the thinning with the mask corresponding to the ink with the smaller ejection amount. It is characterized by that.

  According to the above configuration, the amount of the reaction liquid to be ejected is changed according to the amount of each ink ejected from the recording head to the recording material. In this case, for example, the reaction liquid for the ink having a larger ejection amount is used. By making the amount larger than the amount of reaction liquid for ink rather than the smaller amount of discharge, the amount of ink and reaction liquid can be dealt with without excess or deficiency, which makes it possible to react to the ink discharged onto the recording material. It is possible to prevent the amount of liquid from being too large or conversely too small.

  An ink jet recording method and an ink jet recording apparatus which are the best embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a perspective view showing a schematic configuration of a preferred ink jet recording apparatus for carrying out the ink jet recording method according to the present invention.

  As shown in FIG. 1, the ink jet printer of this embodiment is provided with a transport mechanism 1030 along the longitudinal direction in a casing 1008, whereby a sheet 1028 as a recording medium is indicated by an arrow P shown in the figure. It can be intermittently conveyed in the direction shown. The conveyance mechanism 1030 includes a drive mechanism such as a pair of paper discharge rollers and spurs 1024a and 1024b, a pair of conveyance rollers 1022a and 1022b, and a conveyance motor that drives these roller pairs.

  A guide shaft 1014 is provided in the direction of arrow S in the figure, which is substantially orthogonal to the conveyance direction P of the paper 1028, and the carriage 1010a is provided so as to be movable along the guide shaft 1014. The carriage 1014 includes a head unit (not shown) in which the head chips of the respective inks and reaction liquids are integrally provided, and cartridges 1012S, 1012Y, 1012M, and 1012C that store ink or reaction liquids supplied to the corresponding head chips. 1012K is detachably mounted. Each head chip as a recording head in the head unit includes an ejection port array that ejects ink or a reaction liquid, and these ejection port arrays have a predetermined relationship as described later in FIG. . The head chip of each ink and reaction liquid is provided with an electrothermal conversion element corresponding to the discharge port, and bubbles are generated in the ink using the thermal energy generated by the electrothermal conversion element when an electric pulse is applied. The ink is ejected by the pressure. The head unit, the cartridge 1012S, and the like, and the carriage 1010a on which these are mounted constitute a recording unit 1010. The recording unit scans the paper 1028 in the direction of arrow S in the figure, and each ejection port array is scanned during this scanning. Recording can be performed by discharging the ink and the reaction liquid. In the present embodiment, the permeability of each ink is high and the reaction liquid is low.

  Driving for moving the carriage 1010a is performed by the movement driving unit 1006. The movement drive unit 1006 includes a pulley 1026a and a pulley 1026b attached to a rotation shaft arranged at a predetermined interval in the carriage movement range, and a belt 1016 wound around the pulley 1026a and partially coupled to the carriage 1010a. And a motor 1018 that drives the pulley 1026a to move the belt 1016 in the forward direction and the reverse direction. When the motor 1018 is activated and the belt 1016 rotates and moves in the forward direction, the carriage 1010a of the recording unit 1010 moves in one direction indicated by the arrow S in FIG. 1, thereby causing the recording head in the forward direction. Scanning is possible. When the motor 1018 is activated and the belt 1016 rotates and moves in the reverse direction, the carriage 1010a moves in the direction opposite to the above in the direction indicated by the arrow S, thereby allowing the recording head to scan in the reverse direction. It becomes. A position serving as a home position of the carriage 1010a is defined at one end of the movement range of the carriage 1010a, and a recovery unit 1026 provided with a cap or the like is provided here. Thereby, the discharge recovery process of each chip of the head unit can be performed.

  As a recording head to which the present invention can be applied, a recording head using the thermal energy used in the above embodiment and a piezoelectric element that deforms according to an applied voltage are used, and the deformation of the voltage element is used. A recording head that ejects ink can be used.

  Further, the present invention is characterized by using an ink jet recording head that ejects a plurality of ejection amounts of ink. Here, the amount of ink discharged can be made somewhat by changing the amount of ink discharged from the ink discharge head, for example, by changing the size of the formed discharge port and the size of the heater. Specifically, it may be configured to have a plurality of reaction liquid discharge heads with different discharge amounts. Furthermore, a plurality of heaters corresponding to one discharge port may be provided, and one that can change the discharge amount with one discharge head by selecting the heater to be driven may be used.

  FIG. 2 is a block diagram mainly showing a control configuration of the above-described ink jet recording apparatus. Character or image data to be recorded (hereinafter referred to as “image data”) is input from the host computer to the reception buffer 401 of the recording apparatus. Further, data for confirming whether or not the data is correctly transferred is returned from the recording apparatus to the host computer. The image data received by the reception buffer 401 is transferred to the memory unit 403 under the management of the CPU 402 and temporarily stored in a RAM (Random Access Memory). A mechanical control unit 404 drives a mechanical unit 405 such as a carriage motor or a line feed motor in response to a command from the CPU 402. The sensor / SW control unit 406 sends a signal from the sensor / SW unit 407 including various sensors and SW (switch) to the CPU 402. The display element control unit 408 controls the display element unit 409 such as an LED of the display panel group according to a command from the CPU 402. The head control unit 410 controls the recording head 411 according to a command from the CPU. In addition, the ink jet recording apparatus is driven by a flow in which temperature information indicating the state of the recording head 411 is captured and transmitted to the CPU 402.

  Next, the ink jet recording method of the present embodiment based on the above configuration will be described.

  FIG. 3 is a block diagram showing a data flow or data processing configuration relating to the generation of the reaction liquid ejection data according to the first embodiment of the present invention. Specifically, this data processing is executed by the host computer described above with reference to FIG. 2 or the control unit of the ink jet printer according to the present embodiment based on predetermined software.

  In FIG. 3, a quantizing unit 1000 quantizes the recording data to generate quantized data for discharging each color ink. The reception buffer 1001 receives and temporarily stores the data quantized by the quantization means 1000. The reaction liquid data generation means 1002 generates reaction liquid discharge data from the quantized data for each color ink, and the reaction liquid data generation mask setting means 1004 outputs the reaction liquid discharge data. Master pattern data for thinning used for generating data for use is set. The head controller 1003 discharges the reaction liquid by driving the recording head of the reaction liquid based on the quantized data thus obtained.

  In the above-described configuration, the quantization (means) is performed by the host computer in this embodiment. However, it is needless to say that the present invention is not limited to whether each process shown in FIG. 3 is performed by the host computer or the ink jet printer. All of the above processing may be performed on the ink jet printer side. For example, the host computer executes reaction liquid data generation (means) 1002 and reaction liquid data generation mask setting (means) 1004 to receive the printer. The buffer 1001 may be configured to receive the ejection data of each color ink forming the image and the ejection data of the reaction liquid. As described above, the present invention can be implemented by a combination of a host computer and an inkjet printer, or can be implemented by a single inkjet printer.

  In this specification, not only the latter case but also the former case is included in the ink jet recording apparatus except for the case where there is a special mention.

  Next, the ink jet recording method according to the present invention will be described.

(Embodiment 1)
First, the method of generating reaction liquid data when the ink discharge amount is large and the ink discharge amount is small, and by using a different mask according to the ink discharge amount, the thinning rate of the reaction liquid with respect to ink is changed, A method for applying an optimal amount of the reaction solution will be described.

  The reaction liquid generation process when the ink discharge amount is 5 ng and 2.5 ng will be described as an example. FIG. 4 is a diagram illustrating an example of a reaction liquid generation process when the ink discharge amount is 5 ng and 2.5 ng. Specifically, it is a block diagram showing a method of generating reaction liquid discharge data by thinning out ink discharge data when the ink discharge amounts are 5 ng and 2.5 ng using respective mask data. In this method, reaction liquid discharge data is generated for each pixel for one scan of the recording head.

  In FIG. 4, first, ink discharge data having a discharge amount of 5 ng is generated for the binarized ink recording data 2001 (2002). Here, in the case of so-called one-pass printing in which all the dots to be formed in the scanning area are printed by one scan of the print head, the discharge data is the same as the ink print data 2001 with a discharge amount of 5 ng. Is through. Further, in the case of so-called multi-pass printing, in which the above-described scanning area is recorded by changing the ejection port for ejecting ink by a plurality of scans, the dark cyan ejection data is obtained by thinning out the ink recording data 2001 with the ejection amount of 5 ng. Is generated.

  As the thinning-out method, a conventionally known mask or a method such as so-called sequential multi-scan (SMS) in which ejection ports for sequentially ejecting recording data at a predetermined cycle are assigned to data indicating ejection of recording data, for example. it can.

  The ink discharge data with the discharge amount of 5 ng thus generated by the ink discharge data generation unit 2002 with the discharge amount of 5 ng is sent to the head controller 2010 for the ink with the discharge amount of 5 ng, and the recording head 102 is based on this data. 5 ng of ink is ejected from the 5 ng ink ejection part. The same process is performed for ink with a discharge amount of 2.5 ng.

  Next, a method for generating reaction liquid discharge data will be described. In the present embodiment, separate reaction liquid data extraction masks are used when the ink discharge amounts are 5 ng and 2.5 ng, and thinning is performed using these mask data.

  For the discharge data of the reaction liquid with respect to the ink with the discharge amount of 5 ng, first, the final recording data 2001 of the ink with the discharge amount of 5 ng is thinned with a predetermined mask to generate the reaction liquid data for the discharge amount of 5 ng. (2003), and by generating a logical product (2004) of this and the ejection data of the ejection amount 5 ng of ink ejected by the scanning at that time, which is generated by the ejection data generation means 2002 of the ejection amount 5 ng. This logical product is taken in order to discharge the reaction liquid relating to the reaction liquid data generated by the reaction liquid data generating unit 2003 for the discharge amount of 5 ng in the same scan as the ink and to the same pixel. The same processing is performed for data with a discharge amount of 2.5 ng.

  In the case of discharging from the reaction liquid discharge section based on the reaction liquid discharge data generated in this way, when scanning is performed by the recording head having the configuration shown in FIG. 1 of the present embodiment, the discharge amount is 5 ng and the discharge amount. Each 2.5 ng ink discharge unit scans the same area and discharges each ink. The reaction liquid ejecting section needs to scan the same area for each combination of the ejection amounts of ink and eject the reaction liquid. Therefore, the reaction liquid data for the discharge amount 5 ng of the ink generated by the 5 ng reaction liquid data generation unit 2004 and the reaction liquid data generation unit 2008 for the discharge amount 2.5 ng, which are generated by the combination of inks having different discharge amounts, are generated. The reaction liquid data for the discharged ink of 2.5 ng is logically ORed (2009) and sent to the reaction liquid discharge head control means 2011 as final reaction liquid discharge data.

  FIGS. 5A and 5B are schematic views showing an example of the reaction liquid ejection data extraction mask described above. FIG. 5A shows a reaction liquid extraction mask for dark ink dots, and FIG. 5B shows a reaction liquid extraction mask for light ink dots.

  As shown in these drawings, in this embodiment, a mask for applying a reaction liquid at a duty of 50% for ink with a discharge amount of 5 ng and a duty of 25% for ink with a discharge amount of 2.5 ng is provided. Use. Of course, the mask to be used is not limited to the above-described mask, and the reaction liquid extraction duty for ink with a large ejection amount is set to be higher than the reaction liquid extraction duty for ink with a small ejection amount. That's fine. At this time, the ratio is set in consideration of the ratio of the ink ejection amount and the properties of the ink and the reaction liquid. Furthermore, in the present embodiment, the case where the ink discharge amount is two types of the discharge amount 5 ng and the discharge amount 2.5 ng has been described as an example, but the same processing is performed even when the ink discharge amount is three or more types. As a result, the amount of the reaction solution can be optimized.

  In the case of the present embodiment, as a result of thinning out using the above-described mask, pixels from which ink is ejected include pixels from which only ink is ejected and pixels from which ink and reaction liquid are ejected. As described above, when attention is paid to each pixel, there are cases where the amount of the reaction liquid is large / small with respect to the ink. However, in the entire recording area where the pixels are gathered, the amount of the coloring material applied to the area is reduced. A corresponding amount of reaction solution is applied.

(Embodiment 2)
Next, by using a plurality of reaction liquid portions (hereinafter also referred to as discharge heads) having different discharge amounts of reaction liquid, it is possible to apply inks having different discharge amounts without using a plurality of masks for extracting reaction liquid data. A method for applying an optimum amount of the reaction solution will be described.

  FIG. 6 is a block diagram showing an example of the configuration of the reaction liquid data extraction process of the present embodiment. This figure shows a set of ink with a discharge amount of 5 ng and a discharge amount of 2.5 ng.

  As in the first embodiment, for the recording data 3001 to be recorded with the ink dots with the discharge amount of 5 ng after binarization, the ink discharge data with the discharge amount of 5 ng to be discharged in the scan is generated (3002). The ink discharge data of the discharge amount 5 ng generated by the dark cyan discharge data generation means 3002 is sent to the control means 3004 for the discharge amount 5 ng and also to the reaction liquid discharge head control means 3003 for the ink discharge amount 5 ng. It is done. Based on these data, the discharge is performed from the discharge section 21S2C corresponding to the ink discharge head 21C having a discharge amount of 5 ng and the reaction liquid discharge head for ink having a discharge amount of 5 ng, respectively. Data is generated by the same process for the discharge amount of 2.5 ng ink, and discharge is performed from the discharge head 21LC having a discharge amount of 2.5 ng and the discharge portion 21S3C of the reaction liquid discharge head for ink having a discharge amount of 2.5 ng.

  In the above configuration, the method of generating the reaction liquid discharge data is the same for the discharge amount of 5 ng and the discharge amount of 2.5 ng. However, in the reaction liquid discharge head for ink with the discharge amount of 5 ng, the discharge amount of the reaction liquid is large. The reaction liquid discharge head for 2.5 ng ink has a small reaction liquid discharge amount. As a result, a sufficiently large amount of reaction liquid is applied to the 5 ng ink, and the 2.5 ng ink is discharged. On the other hand, a necessary minimum reaction solution can be applied.

  In addition, the difference in the discharge amount of the reaction liquid discharge head can be made, for example, by changing the size of the discharge port to be formed, the size of the heater, or the like.

  In the above description, an example in which the reaction liquid ejection data is not thinned out with respect to the ink data is shown, but thinning may be performed at a predetermined rate. At that time, since the single discharge amount of the reaction liquid for each of the 5 ng and 2.5 ng inks is optimized with respect to the respective ink discharge amounts, the discharge amount is 5 ng and the discharge amount is 2.5 ng. There is no need to change the extraction ratio of the reaction liquid data for each ink.

  Furthermore, in the above example, the configuration is such that there are a plurality of reaction liquid discharge heads with different discharge amounts, but by providing a plurality of heaters corresponding to one discharge port and selecting the heater to be driven, the discharge amount can be achieved with one discharge head. You may use what can change. In any case, the effect of the present invention can be obtained by increasing the discharge amount of the reaction liquid with respect to the ink having a discharge amount of 5 ng and decreasing the discharge amount of the reaction liquid with respect to the discharge amount of 2.5 ng.

  Further, the discharge amounts of the ink and the reaction liquid are not necessarily the same. What is necessary is just to set so that the discharge amount of the reaction liquid for the ink with a large discharge amount is larger than the discharge amount of the reaction liquid for the ink with a small discharge amount. The discharge amount of the reaction liquid is set in consideration of the properties of the ink and the reaction liquid.

  In this embodiment, the case where the discharge amount is 5 ng and the case where the discharge amount is 2.5 ng are described as examples of the discharge amount of the ink and the reaction liquid. However, in the present invention, the value of the discharge amount is It goes without saying that it is not limited to.

(Embodiment 3)
The reaction liquid data generation process may be performed by the method according to the first embodiment, and the reaction liquid amount may be optimized with respect to the ink discharge amount by changing the discharge amount of the reaction liquid according to the method according to the second embodiment.

(ink)
Next, the ink that can be used in this embodiment will be described. The ink used in the present invention may be a dye ink or a pigment ink as long as it reacts with a reaction liquid described later.

  The dye of the dye ink is used in a range of 1 to 20% by weight, preferably 2 to 12% by weight, based on the total weight of the ink. Further, when the recorded image requires light and shade, the content is preferably 0.01 to 10% by weight. Examples of the dye used include water-soluble acidic dyes, direct dyes, reactive dyes, and dyes that are not listed in the color index, such as sulfonic acid groups and carboxyl groups. And water-soluble dyes having an anionic group. Among the water-soluble dyes herein, those having pH dependency in solubility are included. Among these, an anionic dye is preferable as the color material. The composition of the color material may be selected according to the desired color of the ink. For example, by selecting the color material, yellow, magenta, cyan, black, red, blue or green ink can be prepared. These recording inks of at least one color can be used as an ink set in combination with a cation-containing liquid composition.

  The pigment of the pigment ink is used in a range of 1 to 20% by weight, preferably 2 to 12% by weight, based on the total weight of the ink. Specific examples of the pigment used include carbon black as a black pigment. For example, carbon black produced by the furnace method and the channel method, the primary particle diameter is 15 to 40 mμ (nm), the specific surface area by the BET method is 50 to 300 m 2 / g, the DBP oil absorption is 40 to 150 ml / 100 g, Those having characteristics such as a volatile content of 0.5 to 10% and a pH value of 2 to 9 are preferably used. Examples of commercially available products having such characteristics include No. 2300, no. 900, MCF88, No. 33, no. 40, no. 45, no. 52, MA7, MA8, no. 2200B (manufactured by Mitsubishi Kasei), RAVEN (registered trademark) 1255 (manufactured by Colombia), REGAL400R, REGAL330R, REGAL660R, MOGUL L (manufactured by Cabot), ColorBlack FW1, ColorBlack FW18, ColorBlack S170, ColorBla S170, ColorSla (Registered trademark) 35, Printex (registered trademark) U (manufactured by Degussa), etc., and any of them can be preferably used.

  Examples of yellow pigments include C.I. I. Pigment Yellow 1, C.I. I. Pigment Yellow 2, C.I. I. Pigment Yellow 3, C.I. I. Pigment Yellow 13, C.I. I. Pigment Yellow 16, C.I. I. Pigment Yellow 83 and the like. Examples of magenta pigments include C.I. I. PigmentRed 5, C.I. I. PigmentRed 7, C.I. I. PigmentRed 12, C.I. I. PigmentRed 48 (Ca), C.I. I. Pigment Red 48 (Mn), C.I. I. PigmentRed 57 (Ca), C.I. I. PigmentRed 112, C.I. I. Pigment Red 122 and the like. Examples of cyan pigments include C.I. I. PigmentBlue 1, C.I. I. PigmentBlue 2, C.I. I. PigmentBlue 3, C.I. I. PigmentBlue 15: 3, C.I. I. PigmentBlue 16, C.I. I. PigmentBlue 22, C.I. I. VatBlue 4, C.I. I. VatBlue 6 etc. are mentioned. Of course, the application of the present invention is not limited to these. In addition to the above, pigments such as self-dispersing pigments can also be used.

  The pigment dispersant may be any water-soluble resin, but preferably has a weight average molecular weight in the range of 1,000 to 30,000, more preferably 3,000 to 15,000. Of the range. Specifically, as such a dispersant, for example, styrene, styrene derivatives, vinyl naphthalene, vinyl naphthalene derivatives, aliphatic alcohol esters of α, β-ethylenically unsaturated carboxylic acid, acrylic acid, acrylic acid derivatives, At least two or more monomers selected from maleic acid, maleic acid derivatives, itaconic acid, itaconic acid derivatives, fumaric acid, fumaric acid derivatives, vinyl acetate, vinylpyrrolidone, acrylamide, and derivatives thereof (of which at least 1 One is a block copolymer comprising a hydrophilic polymerizable monomer), a random copolymer, a graft copolymer, or a salt thereof. Alternatively, natural resins such as rosin, shellac and starch can be preferably used. These resins are soluble in an aqueous solution in which a base is dissolved, and are alkali-soluble resins. The water-soluble resin used as the pigment dispersant is preferably contained in the range of 0.1 to 5% by weight with respect to the total weight of the color pigment ink.

  In particular, in the case of a pigment ink containing a pigment as described above, the entire pigment ink is preferably adjusted to be neutral or alkaline. By setting it as such, the solubility of water-soluble resin used as a pigment dispersant can be improved, and it can be set as the pigment ink which was further excellent in long-term storage stability. However, in this case, since it may cause corrosion of various members used in the ink jet recording apparatus, it is desirable that the pH range is 7-10. Examples of the pH adjuster used in this case include various organic amines such as diethanolamine and triethanolamine, inorganic alkali agents such as alkali metal hydroxides such as sodium hydroxide, lithium hydroxide and potassium hydroxide, Examples include organic acids and mineral acids. The above-described pigment and dispersant water-soluble resin are dispersed or dissolved in an aqueous liquid medium.

  As a method for preparing a pigment ink, first, a pigment is added to an aqueous medium containing at least a water-soluble resin as a dispersant and water, mixed and stirred, and then dispersed using a disperser described later. If necessary, a desired dispersion is obtained by performing a centrifugation process. Next, a sizing agent and appropriately selected additive components such as those mentioned above are added to this dispersion and stirred to obtain a pigment ink.

  In addition, when using an alkali-soluble resin as described above as a dispersant, it is necessary to add a base in order to dissolve the resin. Examples of the base at this time include monoethanolamine, Organic bases such as diethanolamine, triethanolamine, amine methyl propanol and ammonia, or inorganic bases such as potassium hydroxide and sodium hydroxide are preferably used.

  In addition, in the method for producing a colored pigment ink containing a pigment, it is effective to perform premixing for 30 minutes or more before stirring and dispersing the aqueous medium containing the pigment. That is, such a premixing operation is preferable because it improves wettability of the pigment surface and promotes adsorption of the dispersant onto the pigment surface.

  The disperser used in the above-described pigment dispersion treatment may be any disperser that is generally used, and examples thereof include a ball mill, a roll mill, and a sand mill. Among these, a high speed type sand mill is preferably used.

  In addition, in an ink jet recording system using an ink containing a pigment, a pigment having an optimum particle size distribution is used from the viewpoint of clogging resistance of an ejection port, etc., but as a method for obtaining a pigment having a desired particle size distribution, , Reducing the size of the grinding media of the disperser, increasing the filling rate of the grinding media, increasing the processing time, slowing the discharge speed, classifying with a filter or centrifuge after grinding, And combinations of these methods.

  A suitable aqueous liquid medium in the above-described dye ink or pigment ink (hereinafter, also simply referred to as ink) is a mixed solvent of water and a water-soluble organic solvent, and water is not general water containing various ions, It is preferable to use ion exchange water (deionized water).

  Examples of the water-soluble organic solvent used by mixing with water include carbon atoms of 1 such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, and the like. Alkyl alcohols of -4; amides such as dimethylformamide and dimethylacetamide; ketones or ketoalcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; polyalkylene glycols such as polyethylene glycol and polypropylene glycol; Ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hexylene glycol, diethylene glycol Alkylene glycols having 2 to 6 carbon atoms, such as coal; glycerin; ethylene glycol monomethyl (or ethyl) ether, diethylene glycol methyl (or ethyl) ether, triethylene glycol monomethyl (or ethyl) ether, etc. Lower alkyl ethers of monohydric alcohols; N-methyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like. Among these many water-soluble organic solvents, polyhydric alcohols such as diethylene glycol and lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl (or ethyl) ether are preferred.

  The content of the water-soluble organic solvent as described above in the ink is generally 3 to 50% by weight, more preferably 3 to 40% by weight, based on the total weight of the ink. The water content used is in the range of 10 to 90% by weight, preferably 30 to 80% by weight, based on the total weight of the ink.

  In addition to the above-described components, a surfactant, an antifoaming agent, a preservative, and the like can be appropriately added as the ink, in order to obtain an ink having desired physical properties as necessary. In particular, a surfactant that functions as a penetration enhancer has a function of promptly penetrating the liquid components of the reaction liquid and the ink into the recording medium, and the addition amount thereof is considered in defining the ink permeability. Is. An example of the amount added is 0.05 to 10% by weight, preferably 0.5 to 5% by weight. As examples of the anionic surfactant, any commonly used ones such as a carboxylate type, a sulfate type, a sulfonate type, and a phosphate type can be preferably used.

(Reaction solution)
Next, the reaction liquid that can be used in this embodiment will be described.

  As the reactant used for the reaction with the dye ink, a cationic substance is preferably used. Specific examples of the cationic substance include, for example, primary to tertiary amine salt type compounds, specifically hydrochlorides such as laurylamine, coconutamine, stearylamine, and rosinamine, acetates, and quaternary ammonium. There are salt-type compounds, specifically lauryltrimethylammonium chloride, lauryldimethylbenzylammonium chloride, benzyltributylammonium chloride, benzalkonium chloride, cetyltrimethylammonium chloride, and further, pyridinium salt-type compounds, specifically There are cetylpyridinium chloride, cetylpyridinium bromide, etc., further imidazoline type cationic compounds, specifically 2-heptadecenyl-hydroxyethylimidazoline, etc., and further ethylene oxide adducts of secondary alkylamines Specifically dihydroxyethyl stearylamine, and the like as a preferable example. As mentioned above, although the example of the cationic substance was given, the cationic substance which can be used for this invention is not necessarily limited to these.

  The reaction liquid used for the reaction with the dye ink may contain water, a water-soluble organic solvent, and other additives in addition to the above-described cationic substance. Examples of water-soluble organic solvents include amides such as dimethylformamide and dimethylacetamide, ketones such as acetone, ethers such as tetrahydrofuran and dioxane, polyalkylene glycols such as polyethylene glycol and polypropylene glycol, ethylene glycol, propylene glycol and butylene. Of alkylene glycols such as glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hexylene glycol and diethylene glycol, polyhydric alcohols such as ethylene glycol methyl ether, diethylene glycol monomethyl ether and triethylene glycol monomethyl ether Lower alkyl ethers, ethanol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol Other monohydric alcohols such as Le, glycerin, N- methyl-2-pyrrolidone, 1,3-dimethylimidazolidinone, triethanolamine, sulfolane, dimethyl monkey Hoki side or the like is used.

  A polyvalent metal salt is a preferable example of the reactant used for the reaction with the pigment ink. The polyvalent metal salt is composed of a divalent or higher polyvalent metal ion and an anion that binds to the polyvalent metal ion. Specific examples of the polyvalent metal ions include divalent metal ions such as Ca 2+, Cu 2+, Ni 2+, Mg 2+, and Zn 2+, and trivalent metal ions such as Fe 3+ and Al 3+. Examples of the anion include Cl-, NO3-, SO4- and the like. In order to form an aggregated film by reacting instantaneously, it is desirable that the total charge concentration of the polyvalent metal ions in the reaction solution is twice or more the total charge concentration of the reverse polarity ions in the pigment ink.

  Examples of the water-soluble organic solvent that can be used in the reaction liquid used for the reaction with the pigment ink include amides such as dimethylformamide and dimethylacetamide, ketones such as acetone, ethers such as tetrahydrofuran and dioxane, polyethylene glycol, and polypropylene. Polyalkylene glycols such as glycol, ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, alkylene glycols such as thiodiglycol, hexylene glycol, diethylene glycol, ethylene glycol methyl ether, Lower alkyl ethers of polyhydric alcohols such as diethylene glycol monomethyl ether and triethylene glycol monomethyl ether, ethanol, In addition to monohydric alcohols such as pill alcohol, n-butyl alcohol and isobutyl alcohol, glycerin, N-methyl-2-pyrrolidone, 1,3-dimethyl-imidazolidinone, triethanolamine, sulfolane, dimethylsulfoxide, etc. Is mentioned. And although there is no restriction | limiting in particular about content of the said water-soluble organic solvent in a reaction liquid, It is 5 to 60 weight% of the total weight of a reaction liquid, Preferably, it is the range of 5 to 40 weight%.

  In addition, the reaction liquid described above may optionally contain additives such as a viscosity modifier, a pH adjuster, a preservative, and an antioxidant as necessary, but the surfactant that functions as a penetration enhancer The selection and addition amount of the agent are considered in defining the permeability of the reaction liquid to the recording medium as described later. Furthermore, the reaction solution is more preferably colorless, but it may be a light color in a range that does not change the color tone of each color ink when mixed with ink on a recording medium. Furthermore, as a suitable range of various physical properties of the reaction liquid as described above, those adjusted so that the viscosity at around 25 ° C. is in the range of 1 to 30 cps are preferable.

  Examples of the present invention will be specifically described below using comparative examples. In the following description, “part” and “%” are based on weight unless otherwise specified.

  First, as described below, pigment inks were obtained which were black, cyan, magenta, and yellow inks each containing a pigment and an anionic compound. Examples of black ink are shown below.

Pigment ink <Preparation of pigment dispersion>
・ Styrene-acrylic acid-ethyl acrylate copolymer (acid value 240, weight average molecular weight = 5,000)
1.5 parts, monoethanolamine 1.0 part, diethylene glycol 5.0 parts, ion-exchanged water 81.5 parts The above ingredients are mixed and heated to 70 ° C in a water bath to completely dissolve the resin component. To this solution, 10 parts of trial pigment blue 15 and 1 part of isopropyl alcohol were newly added, premixed for 30 minutes, and then dispersed under the following conditions.
・ Disperser: Sand grinder (Igarashi Machine)
・ Crushing media: Zirconium beads, 1 mm diameter ・ Filling rate of grinding media: 50% (volume ratio)
-Grinding time: 3 hours Further, centrifugal separation (12,000 rpm, 20 minutes) was performed to remove coarse particles to obtain a pigment dispersion.

Next, the reaction solution will be described. After mixing and dissolving the following components, the reaction solution S was further filtered under pressure with a membrane filter (trade name: Fluoropore Filter, manufactured by Sumitomo Electric) having a pore size of 0.22 μm, and the pH was adjusted to 3.8. Got.

(Composition of reaction solution)
・ Diethylene glycol 10.0 parts ・ Methyl alcohol 5.0 parts ・ Magnesium nitrate 3.0 parts ・ Acetylenol EH (manufactured by Kawaken Fine Chemicals) 0.1 part ・ Ion-exchanged water 81.9 parts

  The color ink tank used in the ink jet recording apparatus 860i (manufactured by Canon) was filled with the reaction liquid S and the pigment ink C, and mounted on the recording head used in the ink jet recording apparatus 850i. In addition, a recording head in which the size of the ejection port was set so that the ink ejection amount was 5 ng and 2.5 ng, and the reaction liquid ejection amount was 2.5 ng was used.

  Then, using the ink jet recording apparatus 850i, solid images 1 to 6 (resolution 1200 dpi) are drawn on plain paper (Super White Paper SW101 (Canon)) at a ratio shown in Table 1 below with the ink ejection duty changed. did. At the time of drawing, the discharge data of the reaction liquid was created based on the method described in the first embodiment. Specifically, when the ink discharge amount is 5 ng, the thinning rate for the ink discharge data of the reaction liquid is 50%, and when the ink discharge amount is 2.5 ng, the thinning rate for the ink discharge data of the reaction liquid Was 25%.

(Comparative Example 1)
Solid images 1 to 6 were prepared in the same manner as in Example 1 except that the thinning rate for the ink ejection data of the reaction liquid was uniformly 25%.

(Comparative Example 2)
Solid images 1 to 6 were prepared in the same manner as in Example 1 except that the thinning rate for the ink ejection data of the reaction liquid was uniformly 50%.

  The color ink tank used in the ink jet recording apparatus 860i (manufactured by Canon) was filled with the reaction liquid S and the pigment ink C, and mounted on the recording head used in the ink jet recording apparatus 850i. Further, a recording head in which the size of the ejection port was set so that both the ink ejection amount and the reaction liquid ejection amount were 5 ng and 2.5 ng was used.

  Then, using the ink jet recording apparatus 850i, solid images 1 to 6 (resolution 1200 dpi) are drawn on plain paper (Super White Paper SW101 (Canon)) at a ratio shown in Table 1 below with the ink ejection duty changed. did. The thinning rate for the ink ejection data of the reaction liquid was uniformly 25%. Further, when drawing, the discharge data of the reaction liquid was created based on the method described in the second embodiment. Specifically, when the ink discharge amount is 5 ng, the reaction liquid discharge amount is 5 ng, and when the ink discharge amount is 2.5 ng, the reaction liquid discharge amount is 2.5 ng.

(Comparative Example 3)
Solid images 1 to 6 were prepared in the same manner as in Example 1 except that the discharge amount of the reaction liquid was uniformly 2.5 ng.

(Comparative Example 4)
Solid images 1 to 6 were prepared in the same manner as in Example 1 except that the discharge amount of the reaction solution was uniformly 5 ng.

（結果）
実施例１，２および比較例１、２，３，４で得られた印字部を、ＶＨ−７０００（キーエンス製）で観察したところ、実施例１，２では、顔料が均一に覆っているように観察され、均一な色として視認できた。これに対し、比較例１，３では、インクの吐出量が５ｎｇのドットの比率が高まるにつれて、紙の下地が露出している箇所の割合が増加していく傾向がみられた。また、比較例２，４では、インクの吐出量が２．５ｎｇのドットの比率が高まるにつれて、顔料の分布が不均一となる傾向がみられた。

(result)
When the printed portions obtained in Examples 1 and 2 and Comparative Examples 1, 2, 3, and 4 were observed with VH-7000 (manufactured by Keyence), in Examples 1 and 2, the pigment seemed to be uniformly covered. Was observed as a uniform color. On the other hand, in Comparative Examples 1 and 3, there was a tendency that the ratio of the portion where the paper base was exposed increased as the ratio of the ink ejection amount of 5 ng increased. In Comparative Examples 2 and 4, the pigment distribution tended to be non-uniform as the ratio of the ink ejection amount of 2.5 ng dots increased.

  Further, when the printed portion was visually evaluated, in Comparative Examples 1 and 3, there was a tendency for color development to decrease, and in Comparative Examples 2 and 4, there was a tendency for solid uniformity to decrease. In contrast, the images obtained in Examples 1 and 2 were good in both solid uniformity and color development.

  As described above, according to the present invention, the amount of the reaction liquid to be ejected is varied according to the ejection amount of each ink ejected from the recording head to the recording material. By increasing the amount of reaction liquid for a large amount of ink to be larger than the amount of reaction liquid for an ink rather than a smaller amount of discharge, the amount of ink and reaction liquid can be handled without excess or deficiency. Therefore, it is possible to prevent the amount of the reaction liquid with respect to the ink to be too large or conversely too small.

  As a result, it is possible to provide an ink jet recording method and an ink jet recording apparatus that can prevent deterioration in image quality due to excess or shortage of reaction liquid and increase in running cost due to increase in the amount of reaction liquid used.

1 is a perspective view showing a schematic configuration of an inkjet recording apparatus in the present invention. 1 is a block diagram showing a general configuration of an ink jet recording apparatus according to the present invention. It is a block diagram which shows the structure of the reaction liquid data generation process concerning 1st embodiment of this invention. It is a block diagram which shows the detailed structure of the reaction liquid data generation process concerning 1st embodiment of this invention. It is a figure explaining the reaction liquid data extraction master data used by this invention. It is a block diagram which shows the structure of the reaction liquid data generation process concerning 2nd embodiment of this invention.

Explanation of symbols

1010 Recording unit 1010a Carriage member 1012 Cartridge 1012Y, M, C, B, S Inkjet cartridge 1014 Guide shaft 1016 Belt 1018 Motor 1020 Drive unit 1022a, 1022b Roller unit 1024a, 1024b Roller unit 1026 Recovery unit 1026a, 1026b Pulley 1028 Paper 1030 Device P Paper transport direction S Scanning direction 401 Reception buffer (control unit)
402 CPU (control unit)
403 Memory unit (control unit)
404 Mechanical control unit (control unit)
405 Mechanical part (control part)
406 Sensor / SW control unit (control unit)
407 Sensor / SW unit (control unit)
410 Recording head control unit (control unit)
411 recording head

Claims (16)

Using a recording head that discharges a plurality of discharge amounts of ink and a recording head that discharges a reaction liquid containing a component that insolubilizes or aggregates the colorant in the ink,
In an ink jet recording method in which recording is performed by applying the ink and the reaction liquid to a recording medium,
An ink jet recording method, wherein the discharge amount of the reaction liquid is varied according to the discharge amount of the ink discharged from the recording head.   The inkjet recording method according to claim 1, wherein the recording head that discharges the plurality of ejection amounts of ink is a recording head that can change the ejection amount of ink at one time.   The inkjet recording method according to claim 1, wherein the recording heads that eject the plurality of ejection amounts of ink are a plurality of recording heads that differ in a single reaction liquid ejection amount.   4. The ink jet recording method according to claim 2, wherein the amount of the reaction liquid with respect to the ink having a larger ejection amount is made larger than the amount of the reaction liquid with respect to the ink having a smaller ejection amount. As a recording head for discharging the reaction liquid, a recording head capable of changing a reaction liquid discharge amount at one time,
The discharge of a larger amount of reaction liquid is performed for ink with a larger discharge amount, and the discharge of a smaller amount of discharge of reaction liquid is performed for an ink with a smaller discharge amount. 4. The ink jet recording method according to 4. As a recording head for discharging the reaction liquid, a plurality of recording heads with different reaction liquid discharge amounts are used,
A printing head with a larger reaction liquid discharge amount is used for ink with a larger discharge amount, and a recording head with a smaller reaction liquid discharge amount is used for an ink with a smaller discharge amount. The ink jet recording method according to claim 4. By generating a reaction liquid discharge data by performing a thinning process using a mask on the ink discharge data for discharging the ink, and by changing the mask in the generation,
7. The ink jet recording method according to claim 4, wherein the amount of reaction liquid for ink with a larger discharge amount is different from the amount of reaction liquid for ink with a smaller discharge amount.   The recording ratio of the reaction liquid generated by the thinning with the mask corresponding to the ink with the larger ejection amount is higher than the recording ratio of the reaction liquid generated by the thinning with the mask corresponding to the ink with the smaller ejection amount. 8. The ink jet recording method according to claim 7, wherein A recording head that discharges a plurality of discharge amounts of ink, and a recording head that discharges a reaction liquid containing a component that insolubilizes or aggregates the colorant in the ink;
In an inkjet recording apparatus that performs recording by applying the ink and the reaction liquid to a recording medium,
An ink jet recording apparatus, wherein a discharge amount of the reaction liquid is varied in accordance with a discharge amount of ink discharged from the recording head.   The inkjet recording apparatus according to claim 9, wherein the recording head that discharges the plurality of ejection amounts of ink is a recording head that is capable of changing a single ejection amount of ink.   The inkjet recording apparatus according to claim 9, wherein the recording heads that eject the plurality of ejection amounts of ink are a plurality of recording heads that differ in the amount of ejection of the reaction liquid at one time.   12. The ink jet recording apparatus according to claim 10, wherein the amount of the reaction liquid with respect to the ink having a larger discharge amount is made larger than the amount of the reaction liquid with respect to the ink having a smaller discharge amount. As a recording head for discharging the reaction liquid, a recording head capable of changing a reaction liquid discharge amount at one time,
The discharge of a larger amount of reaction liquid is performed for ink with a larger discharge amount, and the discharge of a smaller amount of discharge of reaction liquid is performed for an ink with a smaller discharge amount. 12. An ink jet recording apparatus according to item 12. As a recording head for discharging the reaction liquid, a plurality of recording heads with different reaction liquid discharge amounts are used,
A printing head with a larger reaction liquid discharge amount is used for ink with a larger discharge amount, and a recording head with a smaller reaction liquid discharge amount is used for an ink with a smaller discharge amount. The ink jet recording apparatus according to claim 12. By generating a reaction liquid discharge data by performing a thinning process using a mask on the ink discharge data for discharging the ink, and by changing the mask in the generation,
15. The ink jet recording method according to claim 12, wherein the amount of the reaction liquid for the ink having a larger ejection amount is different from the amount of the reaction liquid for the ink having a smaller ejection amount.   The recording ratio of the reaction liquid generated by the thinning with the mask corresponding to the ink with the larger ejection amount is higher than the recording ratio of the reaction liquid generated by the thinning with the mask corresponding to the ink with the smaller ejection amount. 16. The ink jet recording method according to claim 15, wherein the ink jet recording method is performed.

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