JP2007152809A - Ink-jet recorder, recording head, recording method and recorded matter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink-jet recorder which has a high reliability in surface roughness and water absorbing property of a recording medium and provides a printed matter excellent in an image durability and printing density, a recording method, a recording head and a recorded matter. <P>SOLUTION: In the ink-jet recorder which includes at least the first and second recording heads 2-1 and 2-5 for the same color-group ink and the recording heads 2-2, 2-3 and 2-4 for one or more kinds of color ink, at least one of the recording heads for color ink is arranged between the first- and the second recording head for the same color-group ink. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a recording method for corrugated cardboard printing for distribution of fruit and vegetable products, marine products, machine parts, etc., and an ink jet recording method in which both robustness of printed matter and printing quality and reliability of the device are realized, its device, and its recorded matter About.

  As a method for printing contents information and design on the outer layer surface of a cardboard box or the like, predetermined printing is performed by a flexographic printing method or the like in the state of a corrugated cardboard sheet as described in JP-A-5-92554. The printed cardboard sheet is cut and processed into a box by a cardboard box making machine.

Japanese Patent Laid-Open No. 5-92554 (Pages 2 to 3 and FIG. 1)

JP 2002-38063 A

As described above, when printing contents on a corrugated cardboard sheet for logistics, pre-print common parts such as design, name, manufacturer name, etc. indicating the contents in advance by flexographic printing, serial number, Information unique to the contents such as the product destination and lot number is printed by a stamp, a printer or the like after assembling the cardboard, or a label on which the information is printed is attached.
However, when the contents stored in the cardboard box are various, the number of types of cardboard to be preprinted and stocked increases, so that a large space for storage is required.
In addition, since a change in the design requires a change in the version, problems such as inability to respond quickly to the design change have occurred. On the other hand, even when printing unique information, the device costs such as stamps are low when numbering directly on the box, but it is labor-intensive due to manual labor, and printing is extremely uneven, resulting in defective products. The product cost has risen, such as coming out.
Furthermore, when printing variable information specific to labels and attaching them to cardboard, etc., an output machine for printing on the labels and a system for peeling such label liners and attaching them to boxes must be prepared separately. Not only does it cost the label itself.
Further, since a large amount of garbage such as liners is produced, it is not preferable in terms of resource saving. Therefore, using the inkjet recording method, information specific to the contents such as the design, name, manufacturer name and other common parts, serial number, product destination, lot number, etc., which directly describes the contents on the outer surface of the cardboard It is conceivable to solve the above problem by printing simultaneously. However, when recording is carried out on corrugated liner paper using color inks used in consumer printers, sufficient performance is obtained for the robustness of printed matter such as scratch resistance and scratch resistance after water adheres. Or the image was disturbed due to the non-uniform distribution of components on the surface of the recording paper, and the print density was lowered. As a means for enhancing such performance, in addition to using pigments for the ink coloring material, the ink permeability is increased, the coloring material is not left on the surface of the recording medium, and a polymer having a large molecular weight is included in the ink. It is conceivable to increase the binding property to the liner paper by containing a large amount of resin.
However, in the former method, the color material penetrates deep into the recording paper and the image density is lowered, so that a problem occurs in color reproducibility due to the influence of the ground color. In particular, paper used as a cardboard liner is often unbleached, and since the original ground color is dark, if the coloring material penetrates into the liner paper, the visibility and color of the printed matter The reproducibility becomes worse. On the other hand, in the latter method, although the scratch resistance is good, the viscosity of the ink becomes high, ejection in a low temperature environment becomes unstable, the print quality is remarkably deteriorated, and nozzle clogging occurs. Japanese Patent Application Laid-Open No. 2002-38063 solves such a problem by performing a background treatment with white ink, but pigments such as titanium oxide generally used for white ink have a large specific gravity and a remarkable dispersion stability. Since it was bad, a stirrer etc. were needed and caused the enlargement of the machine.
In view of the above circumstances, the present invention has high reliability and image robustness at a site such as a manufacturing factory, a site where goods are stored and shipped such as a distribution warehouse, or a cardboard liner paper printing site. The present invention provides an ink jet recording apparatus, a recording method, a recording head, and a recorded matter that provide a printed matter with an excellent print density.

The above object is achieved by the present invention described below.
That is, the present invention provides an ink jet recording apparatus including at least first and second same color ink recording heads and one or more color ink recording heads. An ink jet recording apparatus in which at least one color ink recording head is disposed between two color ink recording heads of the same color, and a full multi-type recording head is used as the recording head. The first and second recording heads for the same color ink are arranged at both ends of the plurality of color ink recording heads.
In the present invention, it is preferable to use a pigment ink as the first same color ink.
The recording apparatus of the present invention is stored in advance in the non-contact integrated circuit having a function of communicating with a non-contact integrated circuit having a data storage function and a non-contact communication function attached to a recording medium. By having an information reading unit for reading information, it is possible to print specific information such as the shipping date, lot number, destination, etc. in real time on a cardboard or the like without manually inputting the information beforehand.
Furthermore, the present invention relates to a first recording nozzle row for the same color ink and a first recording nozzle row for the same color ink in an ink jet recording head comprising the first and second same color recording nozzle rows and one or more color ink recording nozzle rows. It is characterized by an ink jet recording head in which the color ink recording nozzle row is disposed between two same color ink nozzle recording rows.
Further, the present invention provides an inkjet recording including a step of printing using a first same color system color ink, a step of printing using a second same color system color ink, and one or more types of processes of printing using a color ink. In the method, the method includes a step of printing using the first same color ink and a step of printing a part or all of the region printed with the first same color ink using the second same color ink. The ink jet recording method includes at least one step of printing using color ink between these steps.
These recording methods communicate with a non-contact integrated circuit having a data storage function and a non-contact communication function attached to a recording medium, and print method control information is stored in the unique information stored in advance in the non-contact integrated circuit. By storing, it is possible to print under optimum printing conditions depending on the type of recording medium.
Normally, water-based pigment color inks used in ink jet recording apparatuses use inks with good dispersion stability in the neutral region. Therefore, the ink is a liner on a corrugated liner paper having a neutral to weakly acidic surface pH. Cohesive failure does not occur on the paper surface, ink penetration proceeds, and good print density cannot be obtained. On the other hand, in order to improve productivity in an industrial printing apparatus such as cardboard printing, it is preferable to use a full multi-head to perform printing in one pass, and use of ink that makes the ink dispersion unstable and obtains a print density. It is difficult.
Further, the ink using an aqueous dye has a high printing density even if the dye penetrates to some extent because the dye dyes the fibers of the liner paper. However, due to water solubility, sufficient water resistance cannot be obtained, and there is a problem that the printed surface becomes dirty or print information is lost due to condensation or rain. Therefore, the present inventors have recording heads for the first and second color inks of the same color system, and further, between the first color ink recording head of the same color system and the second color recording head of the same color system. Since the color ink of the same color system is landed after the first color ink is fixed on the liner, the recording head for color ink is disposed on the inner layer and the outer layer liner of the corrugated cardboard. The present invention has led to the provision of an ink jet recording apparatus and a recording method excellent in reliability and enabling image quality.
Furthermore, by taking the position of the first and second same color system color ink recording heads as long as possible in the apparatus, it is possible to obtain a good printed matter without reducing the printing throughput.

The present invention relates to an ink jet recording apparatus, a recording apparatus, and a recording head that perform printing with high water quality on a corrugated cardboard box or inner and outer liner sheets of a corrugated cardboard by printing the same color ink a plurality of times. Is provided. This eliminates the need to have pre-printed cardboard boxes in stock even when a wide variety of cardboards are required, which not only saves space in warehouses and factories, but also responds quickly to design changes. it can. In addition, at the printing site, it is possible to reduce the cleaning process and to specify the ink efficiency because there is no need to create or replace a plate.
Further, by providing a storage element in a cardboard box in advance and storing recording control information, print data, etc., it becomes possible to perform printing under optimum printing conditions depending on the type of the cardboard liner.
Further, according to the present invention, when the pigment ink is applied first, the solid component in the ink fills in the fine irregularities on the surface of the recording medium, and then printing with the dye ink can obtain a printed matter with a good print density without unevenness. it can. Further, by adding an appropriate surfactant to the first ink to increase the permeability, it is possible to provide a system suitable for higher speed printing.
In addition, the present invention has a good print density in which the solid component in the ink reduces the water absorption of the recording medium by hitting the pigment ink first, and then reduces the influence of water absorption without bleeding when printing with the dye ink. Can be obtained. Further, by adding an appropriate surfactant to the first ink to increase the permeability, it is possible to provide a system suitable for higher speed printing.

  The present invention is described in detail below.

FIG. 1 is an external perspective view of the recording apparatus of the present invention. The recording head has a plurality of nozzle rows in order to eject a plurality of types of ink. Each nozzle row is integrally formed by an orifice plate, and includes at least first and second same color ink recording heads, one or more color ink recording heads, and the first same color ink described above. At least one color ink recording head is disposed between the ink recording head and the second color ink recording head.
These recording heads are the illustrated recording heads 2-1, 2-2, 2-3, 2-4, and 2-5. More specifically, the first recording head for the same color ink corresponds to the recording head 2-1, and the second recording head for the same color ink corresponds to the recording head 2-5. Between them, recording heads 2-2, 2-3, and 2-4 for color ink are arranged. The recording medium moves on the belt 4 of the conveying means in the direction of the arrow, and recording is performed on the cardboard conveyed under the recording head. The belt 4 of the conveying means is driven by the conveying roller 3 and rotates.
In order to perform high-speed printing, the recording head is preferably subjected to one-pass recording with an ink jet recording apparatus using a full multi-type head as shown in FIG. At this time, the recording head may be a full multi-head having a recording width, or several heads may be arranged in the recording width direction. However, in cardboard printing that requires high productivity, a fixed long The use of a recording head is preferable for corrugated card printing.
A perspective view of the ink jet recording apparatus is shown in FIG. As shown in the figure, in order to perform high-speed application, recording is performed in one pass with an ink jet recording apparatus using full multi-type recording heads 12-1, 12-2, 12-3, 12-4, 12-5. It is preferable. In this figure, the cardboard 11 (corresponding to 1 in FIG. 1) is transported on the transport device 13, and the recording head 12-1 (corresponding to the recording head 2-1 in FIG. 1), 12-2 (FIG. 1 (corresponding to the recording head 2-4 in FIG. 1), 12-3 (corresponding to the recording head 2-4 in FIG. 1), 12-5 (corresponding to the recording head 2-4 in FIG. 1), 12-5 (corresponding to the recording head 2-4 in FIG. 1) (Corresponding to the recording head 2-5 in FIG. 1).

FIG. 3 is a block diagram schematically illustrating the overall configuration of the recording apparatus. The main electric circuit is composed of a main PCB (Printed Circuit Board) and a power supply unit DU. The main PCB is connected to the host computer HC, and exchanges print data, control data, and ink remaining amount detection data. Here, the power supply unit DU is connected to the printed circuit board unit PCB and supplies various driving powers.
Furthermore, the printed circuit board unit PCB executes drive control of each part of the ink jet recording apparatus in this embodiment, and is provided with a main controller MC, which reads a program stored in the control memory ROM, and And a memory RAM in which control data, timer values, and the like are stored. Further, a communication unit TU that communicates with the host computer HC is connected to the main controller MC. The main controller MC also includes a memory RAM (same color) for storing image data to be recorded, a RAM (C), a RAM (M), a RAM (Y), a RAM (same color), and a control procedure shown in the operation described later. Are connected to the main controller MC. The control memory ROM stores a program corresponding to the head drive circuit HDC. The head drive circuit HDC is connected to the first same color system head, the cyan (C) head, the magenta (M) head, the yellow (Y) head, and the second same color system head. The heads are arranged in the order shown. Here, two heads of the same color system are configured to receive image data from the first and second memory RAMs (same color system), respectively. A common memory may be provided for the first head and the second head, and image data may be input from the common memory. Although an example in which three heads of cyan, magenta, and yellow are arranged has been described, at least one of the three heads of cyan, magenta, and yellow may be arranged according to circumstances.
It is preferable to use a pigment or a dye as the color material used for the ink of the second same color head. The amount of the color material contained in the recording liquid used in the present invention is 0.5 to 20% by weight, and preferably 2 to 12%.
It is particularly preferable to use pigment ink as the first same color ink and dye ink as the second same color ink. When the pigment ink is struck first, the solid component in the ink fills the fine irregularities of the corrugated cardboard liner paper, and then printing with dye ink can provide a printed matter with good print density without unevenness. Further, by adding an appropriate surfactant to the first ink to increase the permeability, it is possible to provide a system suitable for higher speed printing.
Color inks of the same color are usually composed of yellow ink, magenta ink, and cyan ink, but green ink, orange ink, and violet ink may be used to further increase color reproducibility. Is possible. The color ink is composed of a color ink and a black ink having hues other than two types of the same color ink. It is preferable for color reproduction that the same color inks have a CIELAB a * value and b * value coordinate distance of 10 or less when printed on various recording media.
In the operation of the foregoing embodiment, the program stored in the ROM is executed by the CPU, and the solid component in the ink is changed to that of the corrugated liner paper by first hitting the same color pigment ink with the first same color recording head. After filling the minute unevenness, ink of cyan, magenta, and yellow is applied, and then the same color dye ink is printed by the same color recording head, and the portion printed by the first same color recording head is printed again. It is possible to obtain a printed matter having a good print density with no ink. Further, by adding an appropriate surfactant to the first ink to increase the permeability, it is possible to provide a system suitable for higher speed printing.

For the color ink used in the present invention, acidic dyes, basic dyes, direct dyes, organic pigments and inorganic pigments described in the color index can be used. As the pigment, a self-dispersed pigment whose surface has been modified as described above, an aqueous pigment dispersed with a polymer dispersion, and the like can be used.

  Usually, the pigment is dispersed in a water-soluble polymer resin and used in the ink, but the self-dispersing pigment is used in the ink without being dispersed.

  Examples of pigments used in yellow ink include C.I. I. Pigment Yellow 1, C.I. I. Pigment Yellow 2, C.I. I. Pigment Yellow 3, C.I. I. Pigment Yellow 12, C.I. I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 16, C.I. I. Pigment Yellow 17, C.I. I. Pigment Yellow 73, C.I. I. Pigment Yellow 74, C.I. I. Pigment Yellow 75, C.I. I. Pigment Yellow 83, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 95, C.I. I. Pigment Yellow 97, C.I. I. Pigment Yellow 98, C.I. I. Pigment Yellow 109, C.I. I. Pigment Yellow 110, C.I. I. Pigment Yellow 114, C.I. I. Pigment Yellow 128, C.I. I. Pigment Yellow 129, C.I. I. Pigment Yellow 151, C.I. I. Pigment Yellow 154, C.I. I. Pigment Yellow 155 and the like, but are not limited thereto.

  Examples of pigments used as magenta ink include C.I. I. Pigment Red 5, C.I. I. Pigment Red 7, C.I. I. Pigment Red 12, C.I. I. Pigment Red 48 (Ca), C.I. I. Pigment Red 48 (Mn), C.I. I. Pigment Red 57 (Ca), C.I. I. Pigment Red 57: 1, C.I. I. Pigment Red 112, C.I. I. Pigment Red 122, C.I. I. Pigment Red 123, C.I. I. Pigment Red 168, C.I. I. Pigment Red 184, C.I. I. Pigment Red 202 or the like, but is not limited thereto.

  Examples of pigments used as cyan ink include C.I. I. Pigment Blue 1, C.I. I. Pigment Blue 2, C.I. I. Pigment Blue 3, C.I. I. Pigment Blue 15: 3, C.I. I. Pigment Blue 15:34, C.I. I. Pigment Blue 16, C.I. I. Pigment Blue 22, C.I. I. Pigment Blue 60, C.I. I. Vat Blue 4, C.I. I. Vat Blue 60, etc. can be mentioned, but not limited to these.

  Carbon black to be used as a color material for black ink includes furnace method, channel method, high specific surface area carbon produced by activating petroleum coke with a large amount of alkali, and carbon black material as above. On the other hand, it may be a self-dispersing carbon black that has been subjected to a treatment such as fluorine treatment from the gas phase, plasma treatment of a polymerizable monomer having hydrophilicity, or graft polymerization from a liquid phase of hydrophilic monomer.

Carbon black as described above has a primary particle size of 15 to 40 mμ, a specific surface area according to the BET method of 50 to 3000 m ² / g, a DBP oil absorption of 40 to 150 ml / 100 g, and a volatile content of 0.5 to 10 %, The pH value is from 2 to 9.
The water-soluble polymer resin used in the present invention preferably has a weight average molecular weight in the range of 500 to 30,000. If the weight average molecular weight exceeds 30000, the viscosity of the ink becomes high, and stable ejection at low temperatures cannot be obtained. On the other hand, if the weight average molecular weight is less than 500, a sufficient dispersion effect due to steric hindrance cannot be obtained. Specifically, hydrophobic monomers such as styrene, styrene derivatives, vinyl naphthalene, vinyl naphthalene derivatives, alkyl esters of allylic acid, alkyl esters of methacrylic acid, α, β-ethylenically unsaturated carboxylic acids and their aliphatic alcohols Copolymers composed of hydrophilic monomers such as esters, acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid, and derivatives thereof, and salts thereof.

  The copolymer may have any structure such as random, block, and graft, and the acid value is in the range of 80 to 430, preferably 100 to 300. As the water-soluble polymer resin used in the present invention, a water-soluble polymer such as polyvinyl alcohol and carboxymethyl cellulose, a water-soluble resin such as naphthalene sulfonic acid formaldehyde condensate, and polystyrene sulfonic acid can also be used.

The amount of these water-soluble polymer-dispersed resins used is in the range of pigment weight; dispersant weight = 5: 10 to 10: 1 in order to develop sufficient scratch resistance of the printed matter.
The ink of the present invention is mainly composed of water, and a water-soluble solvent is mixed as necessary.
The total amount of the water-soluble solvent is preferably about 30% by weight or less based on the whole recording liquid. In preparing the recording liquid, it is important to select a solvent system in order to adjust storage stability and moisture retention at the nozzle tip. Examples of water-soluble organic solvents that can be used in the present invention include ethylene glycol, diethylene glycol, triethylene glycol, tripropylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, dimethyl sulfoxide, and diacetone. Alcohol, glycerol monoallyl ether, propylene glycol, butylene glycol, polyethylene glycol 300, thiodiglycol, N-methyl-2-pyrrolidone, 2-pyrrolidone, γ-butyrolactone, 1,3-dimethyl-2-imidazolidinone, sulfolane , Trimethylolpropane, trimethylolethane, neopentyl glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl Ether, ethylene glycol monoallyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, β-dihydroxyethyl urea, urea, aceto Nylacetone, pentaerythritol, 1,4-cyclohexanediol, hexylene glycol, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monoisobutyl ether, ethylene glycol monophenyl ether, diethylene glycol diethyl ether, diethylene glycol monobutyl ether, di Tylene glycol monoisobutyl ether, triethylene glycol monobutyl ether, triethylene glycol dimethyl ether, triethylene glycol didiethyl ether, tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol mono Propyl ether, Dipropylene glycol monobutyl ether, Tripropylene glycol monomethyl ether, Glycerin monoacetate, Glycene phosphorus diacetate, Glycene phosphorus triacetate, Ethylene glycol monomethyl ether acetate, Diethylene glycol monomethyl ether acetate, Cyclohexanol, 1, 2 Cyclohexanediol, 1-butanol, 3-methyl-1,5-pentanediol, 3-hexene-2,5-diol, 2,3-butanediol, 1,5-pentanediol, 2,4-pentanediol, 2 , 5-hexanediol, ethanol, n-propanol, 2-propanol, 1-methoxy-2-propanol, furfuryl alcohol, tetrahydrofurfuryl alcohol and the like.
In addition to the above-mentioned materials, surfactants, preservatives, antioxidants, and other auxiliary materials for adjusting physical properties are added to the recording liquid of the present invention as auxiliary agents for ejection stability, flow characteristics, and dispersion stability. I can do it. As the surfactant, nonionic surfactants, amphoteric surfactants, cationic surfactants and the like can be used.

  As a method for producing the ink of the present invention, first, a water-soluble polymer resin is dissolved in an aqueous base solution, a pigment is added to the aqueous solution, the surface of the pigment is wetted by premixing, and then the dispersing means described later is used. Dispersion is performed, and centrifugal separation, pressure filtration using a membrane, etc. are performed to remove coarse particles, and a desired dispersion is obtained.

Next, the above-mentioned solvent is added to this dispersion, and other additives (surfactant, pH adjuster, preservative, etc.) are added as necessary, and stirred to obtain a recording liquid.
In addition, it is preferable that the ink used in the present invention is used after being washed and purified in order to remove impurities. Commercial pigments contain a large amount of organic and inorganic impurities, and these impurities adversely affect nozzle clogging, kogation, storage stability, recording reliability, etc. It is preferable to use after washing and purification. Examples of washing and purification methods include filtration, centrifugation, separation membrane method, ion exchange resin treatment method, reverse osmosis method, activated carbon method, zeolite method, water washing, solvent extraction and the like. Washing and purification may be performed before mixing the raw materials, after preparing the dispersion, after preparing the ink, or may be performed in a plurality of stages.

  In particular, since the mixing route of such impurities is considered to be from the color material, the dispersion medium at the time of dispersion, and the dispersion container, the treatment before mixing the raw materials or after adjusting the dispersion is effective.

  FIG. 3 shows another ink jet recording apparatus using the present invention. In this apparatus, a plurality of recording heads 32 are arranged at right angles to the conveyance direction of the recording medium. These recording heads are mounted on a carriage and perform printing by a serial scan method by moving on a shaft 26. In this apparatus, five sets of recording heads are mounted. Pigment ink is ejected to the most upstream same-color recording head 33-1 and dye ink is ejected to the most downstream same-color recording head 33-5. The present invention is implemented by ejecting cyan, magenta, and yellow color inks 3 and 4.

  Further, the recording apparatus includes a non-contact communication unit 29 including an antenna for RF-IF communication, and a non-contact integrated circuit (RF tag or the like) having a data storage function and a non-contact communication function previously attached to the cardboard. It is also possible to execute predetermined printing on the cardboard based on information acquired by executing communication with the terminal 27.

  Examples of the control information stored in the non-contact integrated circuit attached to the cardboard include the material of the recording medium, the printing method, and color designation. In particular, since the type of coat layer on the surface of the cardboard box varies depending on the application, printing the control information for the pigment ink printing process and dye ink printing process on the storage medium in advance enables printing on the cardboard in the best printing process. It is possible to

FIG. 5 is a block diagram schematically illustrating the overall configuration of the recording apparatus. The main electric circuit is composed of a main PCB (Printed Circuit Board) and a power supply unit DU. The main PCB corresponds to the controller 21 shown in FIG. 4 through a recording head 32, a cable 24, and a drive box 28. Combined, print data, control data, and ink remaining amount detection data are exchanged. Here, the power supply unit DU is connected to the printed circuit board unit PCB and supplies various driving powers.
Furthermore, the printed circuit board unit PCB executes drive control of each part of the ink jet recording apparatus in this embodiment, and is provided with a main controller MC, which reads a program stored in the control memory ROM, and And a memory RAM in which control data, timer values, and the like are stored.

  Further, a communication unit TU that communicates with the host computer HC is connected to the main controller MC.

  The main controller MC also corresponds to a memory RAM (same color) for storing image data to be recorded, RAM (C), RAM (M), RAM (Y), RAM (same color), and an operation description to be described later. A control memory ROM storing a program corresponding to the control procedure, an RF-ID reader / writer RW communicating with the RF-ID tag, an antenna ANT communicating with the RF-ID tag 27, and a head driving circuit HDC are provided in the main controller MC. It is connected.

Further, a distance measuring unit DM between the danbo 30 and the recording head 32 of the recording medium, an XYZ triaxial driving motor M, and a remaining amount detecting unit for detecting the remaining amount of ink in the ink containing unit that supplies ink to the recording head 32 The RD, the power supply unit DU, and the main controller MC are connected. The remaining amount detection unit RD is attached to the inside of the ink storage unit attached to the carrier unit 25, and outputs a signal to the printed circuit board unit PCB when the remaining amount of ink becomes below a certain level, and makes the carrier unit 25 an ink replenishment unit. After being moved and coupled with a coupling unit (not shown) of the ink replenishing unit, a predetermined amount of ink is replenished using the above-described ink remaining amount detecting unit.
As the ink remaining amount detection unit RD, a method in which several electrodes are arranged inside the ink storage unit, and the amount of movement between the electrodes is measured to detect the remaining amount of ink is inexpensive and highly reliable. When using non-conductive ink, a method of optically detecting the presence or absence of ink, a method of detecting a pressure that can be changed according to the remaining amount of ink in the ink tank by providing a pressure sensor or the like in the ink tank Although it is possible to use a method of counting printing dots, in a method that cannot be used in combination with ink fullness at the time of ink replenishment, it is necessary to provide a full tank detection means in the ink containing portion. Ink replenishment can be performed for at least one color at the same time depending on the amount of ink remaining, thereby shortening the time required for ink replenishment.
Further, a remaining amount detection unit may be provided in the ink replenishment unit. In the present invention, it is important to keep the distance between the recording head and a predetermined recording surface of the three-dimensional structure constant in order to obtain a high-quality printed matter such as a pattern or a two-dimensional barcode.

This is because slight nozzle unit variations that occur due to differences in the recording head manufacturing process affect the ink discharge amount and the direction of the discharge direction of each nozzle, and ultimately deteriorate the image quality as density unevenness of the printed image. It becomes. In particular, these variations are largely due to variations in the ejection direction of the ejected ink droplets. Therefore, if the distance between the recording head and the recording surface is increased, the print quality is greatly affected. On the other hand, if the distance between the recording head and the recording surface is made too small, the recording head is slid on the recording surface, which not only contaminates the recording surface but also damages the recording head. Therefore, by providing the distance measuring unit DM for measuring the distance between the recording head and the recording surface, it is possible to form a high-quality image at an arbitrary position of the three-dimensional structure without bringing the recording head into contact with the recording medium. It is.
The distance measuring method used in the present invention may be a method using ultrasonic waves. Further, by detecting the end surface of the three-dimensional structure using the distance measuring unit DM, the conveyor can be stopped at a predetermined position from the end surface and printing can be executed. Further, since the distance measuring unit DM is integrally formed with the carrier unit 25, it is possible to detect an end surface orthogonal to the conveying direction of the conveyor by sliding the carrier unit 25 along the XYZ shaft unit 26. Yes, it is possible to execute printing at a desired position of the three-dimensional structure.

The non-contact communication unit 29 used in the ink jet recording apparatus of the present invention corresponds to the RF-ID communication antenna ANT shown in the outline of the control unit in FIG. This enables communication with a non-contact integrated circuit (RF tag or the like) having a contact communication function. Information to be acquired from the RF-ID tag 27 is transmitted to the communication antenna 29 and the RF-ID reader / writer RW. Via the main controller MC. The main controller MC and the head drive circuit HDC convert the acquired print data and control data into control signals and image information, and send them to the drive units of the recording heads and the shafts to execute predetermined printing on the three-dimensional structure. To do.
The antenna 29 attached to the recording apparatus of the present invention is on a plane parallel to the antenna of the RF-ID tag 27 attached to the cardboard box 30 having a three-dimensional structure in order to enable the best communication state. An antenna 29 is attached to the bottom surface of the carrier portion 25. At that time, it is also possible to write information from the control unit to the non-contact integrated circuit as necessary.
The control information stored in the non-contact integrated circuit of the RF-ID tag 27 attached to the three-dimensional structure includes the recording medium material, printing method, color designation, cardboard box size information, and recording surface information. Size information etc. are mentioned. In particular, since the type of the coat layer on the surface of the cardboard box differs depending on the application, printing control according to the type, for example, in the case of a medium that easily bleeds, processing such as thinning out dots is important. Therefore, it is possible to automatically set the optimum print control by storing the type and the printing method of the cardboard box 30 in the non-contact integrated circuit of the RF-ID tag 27 in advance and reading them at the printing stage. .
As a result, even if various types of cardboard boxes are randomly transported to one belt conveyor, optimum printing can be performed without input by the operator.
In the operation of the foregoing embodiment, the program stored in the ROM is executed by the CPU, and the solid component in the ink is changed to that of the corrugated liner paper by first hitting the same color pigment ink with the first same color recording head. After filling the minute unevenness, cyan, magenta and yellow inks were applied, and then the same color dye ink was printed with the same color dye head by the same color print head with the second same color. When printing is performed again with the recording head of the system, a printed matter having a uniform print density can be obtained. Furthermore, printing suitable for higher-speed printing can be performed by adding an appropriate surfactant to the first ink to increase the permeability.

FIG. 6 shows another embodiment of the recording head of the present invention. The recording head has a plurality of nozzle rows in order to eject a plurality of types of ink. Each nozzle row is integrally formed by an orifice plate, and a color is provided between the nozzle row 41-1 for the first same color color ink and the nozzle row 41-5 for the second same color ink. Ink nozzle rows 41-2, 41-3, and 41-4 are arranged.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.
(Black ink adjustment)
C. I. Direct Black 154 (manufactured by Orient Chemical Co., Ltd.) 5 parts triethylene glycol 2 parts glycerin 7 parts ethylene glycol 10 parts acetylenol EH (manufactured by Kawaken Fine Chemicals Co., Ltd.) 0.5 part ion-exchanged water remaining After stirring the above composition for 3 hours, 0 The solution was filtered through a 45 micron membrane filter. .
(Adjustment of the first yellow ink)
(Preparation of pigment dispersion) Lithium hydroxide solution of styrene / acrylic acid / ethyl acrylate copolymer (glass transition temperature 74 ° C., acid value 180, weight average molecular weight 9000) (neutralization rate 130%, resin solid content 2. 5 parts) was washed with pure water in a solution containing 80 parts and ethylene glycol 10 parts. I. After adding 12 parts of Pigment Yellow 74, premixing was performed, followed by dispersing for 5 hours using a sand mill, and after dispersion, centrifugation (10000 rpm, 1 hour) was performed to remove coarse particles. The dispersion had a solid content of about 11%.
(Create ink)
30 parts diethylene glycol 8 parts glycerin 10 parts acetylenol EH (manufactured by Kawaken Fine Chemicals Co., Ltd.) 0.5 parts ion-exchanged water The remaining composition was stirred for 3 hours, and then filtered through a 1 micron membrane filter. Further, impurities such as calcium were removed through the ion exchange resin layer to obtain a desired recording liquid.
(Adjustment of second yellow ink)
C. I. ACID YELLOW 23 1.5 parts diethylene glycol 8 parts glycerin 10 parts acetylenol EH (manufactured by Kawaken Fine Chemicals Co., Ltd.) 0.1 part ion-exchanged water The remainder The above composition was stirred for 3 hours and then passed through a 0.45 micron membrane filter. Filtered.
(Adjusting magenta ink)
(Preparation of pigment dispersion) Potassium hydroxide solution of styrene / acrylic acid / butyl acrylate copolymer (glass transition temperature 53 ° C., acid value 180, weight average molecular weight 12000) (neutralization rate 130%, resin solid content 2. 5 parts) in a solution containing 80 parts and diethylene crycol 5 parts. I. After adding 15 parts of Pigment Red122, dispersion was performed with a sand mill for 8 hours to obtain an aqueous dispersion. This dispersion was centrifuged (15000 rpm, 0.5 hour), coarse particles were removed, and an aqueous dispersion was prepared. The dispersion had a solid content of about 13%.
(Create ink)
40 parts ethylene glycol 10 parts glycerin 8 parts diethylene glycol 10 parts acetylenol EH (manufactured by Kawaken Fine Chemicals Co., Ltd.) 0.5 part ion-exchanged water The remainder The above composition was stirred for 3 hours and then filtered with a 1 micron membrane filter. Filtered. Further, inorganic impurities were removed through the ion exchange resin layer to obtain a desired recording liquid.
(Cyan ink adjustment)
(Preparation of pigment dispersion) Potassium hydroxide solution of styrene / acrylic acid / ethyl acrylate copolymer (glass transition temperature 77 ° C., acid value 140, weight average molecular weight 6000) (neutralization rate 125%, resin solid content 5 parts) ) Was washed with pure water in a solution containing 80 parts of ethylene glycol and 5 parts of ethylene glycol. I. Pigment Blue 15: 3 15 parts were premixed and then dispersed in a sand mill for 3 hours to prepare an aqueous dispersion. The dispersion had a solid content of about 14%.
(Create ink)
40 parts diethylene glycol 8 parts glycerin 8 parts triethylene glycol 8 parts diethylene glycol monobutyl ether 0.5 parts Surfinol 465 (Nissin Chemical Industry Co., Ltd.) 0.5 parts ion-exchanged water The remainder The above composition is stirred for 3 hours And filtered through a 2 micron membrane filter.
5 types of ink are filled in the ink cassette of the ink jet recording apparatus shown in FIGS. 1 and 2, and on OFC 210 g / m ² (cardboard liner, made by Oji Paper) and OFC 170 g / m ² (cardboard liner, made by Oji Paper) An image was formed. Each recording head is arranged in the order of a first yellow ink recording head, a cyan ink recording head, a magenta ink recording head, a black ink recording head, and a second yellow ink recording head.

Comparative example

BK, M, and C inks similar to those in Example 1 were used. As the Y ink, the first ink used in the examples was used. Each recording head is arranged in the order of a black ink recording head, a cyan ink recording head, a magenta ink recording head, and a yellow ink recording head.
Evaluation of the printed matter printed by the Example and the comparative example was implemented about each following item.

(Color reproducibility)
A solid pattern printed using yellow, magenta, cyan, and black inks was visually compared with that printed on copy paper using the same ink.

(Abrasion)
The solid print portion was rubbed with a load of 200 g / cm ² , and the stain on the non-recorded portion was visually observed.

(Water scratch resistance)
One drop of tap water was dropped on the solid print portion, and a load of 200 g / cm ² was applied to the solid print portion and rubbed, and the stain on the non-recorded portion was visually observed.
(Fixability)
The non-printing part after the solid printing part is visually observed and determined by the presence or absence of a spur mark.

Evaluation results

The printed matter printed by the ink jet recording method of the present invention gave good results in the above test.

Schematic diagram of the inkjet recording method of the present invention External perspective view of the recording apparatus of the present invention Block diagram of the recording apparatus of the present invention External perspective view of an ink jet recording apparatus according to another embodiment of the present invention. Block diagram of the recording apparatus of the present invention The figure which shows the recording head by other Example of this invention.

Explanation of symbols

1. Corrugated board 2-1, 2-2, 2-3, 2-4, 2-5 Inkjet recording head 3 Conveying roller 4 Conveying belt Recording unit 11 Corrugated cardboard 12-1, 12-2, 12-3, 12-4, 12-5 Full multi-type recording head 13, 14 Conveying belt 15, 15 Conveying roller 21 Controller 22 Computer 25 Carriage 26 Drive shaft 27. RF tag 28. Drive box 33-1, 33-2, 33-3, 33-4, 33-5 Inkjet recording head 41-1, 41-2, 41-3, 41-4, 41-5 Nozzle array

Claims (17)

In an ink jet recording apparatus comprising at least first and second color ink recording heads and one or more color ink recording heads, the first same color ink recording head and the second same color system An ink jet recording apparatus, wherein at least one color ink recording head is disposed between color ink recording heads. The inkjet recording apparatus according to claim 1, wherein a full multi-type recording head is used as the recording head. 3. The ink jet recording apparatus according to claim 1, wherein the recording head for the same color ink includes a recording head for yellow ink, a recording head for magenta ink, and a recording head for cyan ink. 4. The ink jet recording apparatus according to claim 1, wherein the first same color ink includes a pigment as a color material. 2. The ink jet recording apparatus according to claim 1, wherein the first same color system color ink recording head and the second same color system color recording head are disposed at both ends of the color recording head. 6. An ink jet recording apparatus according to claim 1, further comprising a communication unit having a function of communicating with a non-contact integrated circuit having a data storage function and a non-contact communication function attached to a recording medium. The ink jet recording apparatus according to claim 1, further comprising an information reading unit having a function of reading information stored in advance in the non-contact integrated circuit. 8. The ink jet recording apparatus according to claim 1, further comprising a writing unit having a function of writing information to the non-contact integrated circuit. The type of recording medium, color designation information, print start position, memory for storing control information including the print area where the first and second color inks of the same color are printed, and recording is performed based on the control information And a control means for controlling the recording means. In the inkjet recording head, in the inkjet recording head comprising at least the first and second color ink recording nozzle rows and one or more types of color ink recording nozzle rows in the ink jet recording head, An ink jet recording head, wherein at least one of the color ink recording nozzle rows is arranged between the second same color ink recording nozzle rows. 10. The ink jet recording head according to claim 9, wherein the recording head for the same color ink includes a recording nozzle row for black ink, a recording nozzle row for yellow ink, a recording nozzle row for magenta ink, and a cyan ink recording nozzle row. An ink jet recording head, wherein the first same color ink recording nozzle array and the second same color ink recording nozzle array are arranged at both ends of the color recording nozzle array constituting the recording head. In an inkjet recording method comprising: a step of printing using at least a first same color ink, a step of printing using a second same color ink, and one or more types of steps of printing using a color ink. At least one step of printing using the color ink is included between the step of printing using the same color system color ink and the step of printing using the second color system color ink. Inkjet recording method. A first step of communicating with a non-contact integrated circuit having a data storage function and a non-contact communication function attached to the recording medium, and reading the specific information stored in advance in the non-contact integrated circuit; The inkjet recording method according to claim 12, further comprising a second step of creating print data based on the unique information and a third step of performing printing based on the print data. Communicating with a non-contact integrated circuit having a data storage function and a non-contact communication function attached to the recording medium, and reading the control information stored in advance in the non-contact integrated circuit; The inkjet recording method according to claim 12, further comprising a second step of controlling a printing method based on the control information. 21. An ink jet recording device produced by using the ink jet recording apparatus or recording method according to claim 1 or a recording head. The recording method according to claim 13, wherein the recording medium is a cardboard liner paper.

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