JP2006123529A - Ink jet recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink jet recording apparatus which is a two-liquid-type ink jet apparatus for executing printing by a UV-curing type ink and can simplify and downsize the structure of a recording head and prevent partial deterioration of print quality due to unevenness of mixture by sufficiently mixing and stirring two liquids. <P>SOLUTION: A merged supply channel 45 at which a first ink channel 41 connected to a first ink reservoir 21 and a second ink supply channel 43 connected to a second ink reservoir 22 are merged is provided in an ink supply channel 15 for supplying an ink liquid from the first and second ink reservoirs 21 and 22 to the recording head 9. The two liquids are mixed and stirred by merging in the merged supply channel 45 and supplied to the recording head 9 as the UV curing type ink. Improvement of printing quality by uniformly mixing the two liquids and simplification and downsizing of the structure of the recording head 9 are realized. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ink jet recording apparatus for recording an image such as a character or a graphic on a recording medium by using an ultraviolet curable ink generated by mixing two liquids of a first ink liquid and a second ink liquid. Is.

  An ink jet recording apparatus ejects droplets of ink liquid (ink composition) onto a recording medium such as paper by a recording head to record an image such as characters and graphics on the recording medium. By miniaturizing the liquid droplets, a high-resolution and high-quality image can be printed at high speed.

The ink liquid used in such an ink jet recording apparatus is generally a so-called aqueous ink containing an aqueous solvent as a main component and containing a coloring component and a wetting agent such as glycerin for the purpose of preventing clogging. .
However, when the recording medium is made of paper, cloth, or metal, plastic, or the like that does not allow water-based ink to permeate, general water-based inks have poor ink penetration and poor ink fixation. Therefore, stable printing cannot be performed.
Therefore, it has been proposed to use an ultraviolet curable ink containing a component that is polymerized by application of ultraviolet rays for printing on a recording medium in which aqueous ink does not penetrate or does not penetrate.

  As an inkjet recording apparatus that performs printing with ultraviolet curable ink, initially, an ultraviolet curable ink itself in which a coloring material, an ultraviolet curable agent, a polymerization initiator, and the like are mixed at a predetermined ratio is stored in an ink storage unit. One-pack type was the mainstream. However, the ultraviolet curable ink mixed with a coloring material, an ultraviolet curing agent, a polymerization initiator, etc., gradually undergoes a polymerization reaction during storage, so it is difficult to stably maintain the physical properties of the ink liquid such as viscosity, The change in the physical properties of the ink liquid may cause a decrease in printing performance.

Therefore, as an ink jet recording apparatus that performs printing with ultraviolet curable ink, in the apparatus, ultraviolet curable ink includes a first ink liquid that is an ink composition including a color material, and a reaction liquid that includes a polymerization initiator. By separately storing the two liquids separated into two liquids that function as a second ink liquid, and contacting these two liquids on the recording medium, a coloring material, an ultraviolet curing agent, a polymerization initiator, etc. A two-component type has been proposed that exhibits a function as a mixed ultraviolet curable ink (see, for example, Patent Document 1, Patent Document 2, Patent Document 3, and Patent Document 4).
Such a two-pack type can suppress changes in the physical properties of each ink liquid during storage and improve the storage stability of each ink liquid, so that stable printing performance can be maintained over a long period of time. Can do.

JP 2003-12971 A Japanese Patent No. 3478495 JP 2002-275403 A JP 2000-119574 A

However, in the conventional method in which the two liquids of the first ink liquid and the second ink liquid constituting the ultraviolet curable ink are mixed on the recording medium, an ejection control mechanism for ejecting fine ink droplets is provided for each ink. There is a problem that the configuration of the recording head incorporating the ejection control mechanism becomes complicated and the recording head becomes large.
In addition, the droplets of each ink liquid ejected from the recording head come into contact with each other by being ejected so as to overlap at the same location on the recording medium. It is difficult to achieve a uniform mixed state, and there is a possibility that the printing quality is partially deteriorated due to unevenness of the mixing reaction or uneven color due to uneven mixing.

  Accordingly, an object of the present invention is to solve the above-described problems, and is an ink jet recording apparatus that executes printing with a two-component type ultraviolet curable ink, and is intended to simplify and reduce the size of the recording head. In addition, the two liquids can be sufficiently mixed and stirred to prevent partial deterioration in print quality due to non-uniform mixing, and to achieve high-quality and stable printing without uneven printing It is to provide a recording device.

  The above object is achieved by the following configuration.

(1) a first ink storage section that stores the first ink liquid;
A second ink reservoir that stores a second ink that produces ultraviolet curable ink by being mixed with the first ink;
A recording head for discharging the first ink liquid and the second ink liquid onto a recording medium;
An ink supply path for supplying ink liquid from each ink reservoir to the recording head;
An inkjet recording apparatus comprising: an ultraviolet irradiation unit configured to irradiate ultraviolet rays onto the recording medium on which the ultraviolet curable ink is applied by the recording head;
The ink supply path has a first ink supply path with one end connected to the first ink storage part, a second ink supply path with one end connected to the second ink storage part, and one end with the first and second ink supply paths. A confluence supply path connected to the other end of the second ink supply path and connected to the recording head at the other end to mix and stir the two liquids of the first ink liquid and the second ink liquid. Prepared,
The first ink liquid supplied from the first ink storage part and the second ink liquid supplied from the second ink storage part are mixed and agitated by joining together in the joint supply path, so that ultraviolet curable ink is obtained. An ink jet recording apparatus, wherein the ink jet recording apparatus is supplied to a recording head.
(2) The merging supply path includes a cylindrical housing in which the first ink liquid and the second ink liquid merge and flow, and liquid that is fixedly installed in the cylindrical housing and flows in the cylindrical housing. The ink jet recording apparatus according to (1), wherein the ink jet recording apparatus is a static mixer including an element that causes a change in direction or division.
(3) The first ink liquid is an ink liquid containing at least a color material, and further contains a polymerization accelerator and / or a polymerization compound or a polymerization initiator, and the second ink liquid is a color material. The ink jet recording apparatus according to (1) or (2), wherein the ink recording liquid contains no polymerization compound, a polymerization initiator, and / or a polymerization accelerator.
(4) The inkjet recording apparatus according to (3), wherein the color material of the first ink liquid is a pigment.

  The operational effects achieved by the ink jet recording apparatus described in (1) will be described with reference to specific examples of the first ink liquid and the second ink liquid. In the apparatus, the ultraviolet curable ink contains a coloring material. Since each of the first ink liquid, which is an ink composition, and a second ink liquid containing a polymerization initiator and functioning as a reaction liquid are separately stored in two liquids, Since it has the advantage of a two-part type that can suppress changes in physical properties of the ink liquid and the storage stability of each ink liquid is improved, stable printing performance can be maintained over a long period of time.

  In the ink jet recording apparatus described in (1), the ink liquids stored in the ink storage units independent from each other are individually separated from the ink storage units by the first ink supply path and the second ink supply path. One of the ultraviolet curable inks produced by mixing and stirring in the merging supply path where the first ink supply path and the second ink supply path join together is fed to the recording head. The liquid is supplied to the recording head.

  Therefore, although it is a two-component type, it is possible to simplify and miniaturize the configuration of the recording head by using a single ejection control mechanism incorporated in the recording head for controlling ejection of fine ink droplets.

  In addition, the two liquids of the first ink liquid, which is an ink composition including a color material, and the second ink liquid that includes a polymerization initiator and functions as a reaction liquid appropriately adjust the length of the merging supply path. When set to, sufficient mixing and stirring can be performed. Therefore, compared to the conventional two-pack type in which the two liquids are mixed by contact with the ink liquid on the recording medium, the two liquids are sufficiently mixed and stirred. Thus, it is possible to prevent the printing quality from partially deteriorating due to non-uniform mixing, and to realize high-quality and stable printing without printing unevenness.

  In the ink jet recording apparatus described in (2) above, since the merged supply path for mixing the two liquids is configured with a static mixer, a high mixing and stirring performance is obtained, and the element for mixing the two liquids is used. By devising the shape and the like, necessary and sufficient uniform mixing can be obtained even if the length of the merging supply path is shortened, and the apparatus can be miniaturized by shortening the merging supply path.

  In addition, since the static mixer has fixed elements and no moving parts, it can improve the sound quality of the apparatus. Further, there is no malfunction due to wear of the movable part, and stable mixing and stirring performance can be maintained over a long period of time.

  As described above, as the first ink liquid, an ink liquid containing at least a coloring material and further containing a polymerization accelerator and / or a polymerization compound or a polymerization initiator can be used. In addition, as the second ink liquid, an ink liquid that does not contain a coloring material and that contains a polymerization compound, a polymerization initiator, and / or a polymerization accelerator can be used.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of an ink jet recording apparatus according to the invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view of a main part of an embodiment of an ink jet recording apparatus according to the present invention.
The ink jet recording apparatus 1 according to this embodiment is a two-component recording apparatus that performs desired printing with ultraviolet curable ink, and includes a first ink storage unit 21 that stores a first ink liquid, and a first ink. A second ink storage unit 22 storing a second ink liquid that generates ultraviolet curable ink by being mixed with the liquid, and the first ink liquid and the second ink liquid on a recording medium 7 such as paper. A recording head 9 for discharging, a carriage 11 on which the recording head 9 is mounted and driven to reciprocate in the main scanning direction (width direction of the recording medium 7) indicated by an arrow B, and a recording medium in the sub-scanning direction orthogonal to the main scanning direction 7, a recording medium transport mechanism 13 that transports the ink 7, an ink supply path 15 that supplies ink liquid from the ink storage units 21 and 22 to the recording head 9, and the recording medium on which the ultraviolet curable ink is applied by the recording head 9. And a UV irradiation unit (not shown) is irradiated with ultraviolet rays on the 7.

  In the case of the present embodiment, the first ink liquid is an ink composition containing at least a polymerization initiator or a polymerization compound, or a polymerization compound, a polymerization accelerator, and a coloring material, and the second ink liquid is It contains a polymerization compound, a polymerization initiator and / or a polymerization accelerator, and functions as a reaction liquid that starts curing of the ink liquid by a polymerization reaction of the resin material when mixed with the first ink liquid.

  Specifically, various combinations of the component compositions of the first ink liquid and the second ink liquid are conceivable as shown in Table 1 below.

  A pigment can be used as the color material of the first ink liquid. Further, both the first ink liquid and the second ink liquid are prepared as a solvent-free system containing no solvent.

  As the recording medium 7, various materials such as paper, cloth, or a metal, plastic, or the like that does not penetrate water-based ink can be used as long as it is a sheet that can be conveyed by the recording medium conveyance mechanism 13. is there.

The carriage 11 is supported by a guide shaft 25 so as to be movable in the main scanning direction B, and is moved and scanned to an arbitrary position in the main scanning direction by a driving belt 29 driven to reciprocate by a transport motor 27.
The recording medium transport mechanism 13 feeds the recording medium 7 in the sub-scanning direction by the rotation of the cylindrical platen 13 a that contacts the surface of the recording medium 7.
The feeding operation of the recording medium 7 by the recording medium transport mechanism 13 is controlled in synchronization with the reciprocating operation of the carriage 11.

  At the standby position of the carriage 11 (in the vicinity of the right-hand side wall as viewed from the front), the head cleaning means 31 for eliminating clogging of the ink discharge ports of the recording head 9 and the ink discharge ports of the recording head 9 are covered. A cap member 33 for preventing the ink discharge port from being dried is provided.

The ink supply path 15 in the present embodiment is made of an elastic resin, and as shown in FIG. 2, the first ink supply path 41 having one end connected to the first ink reservoir 21 and the second end being a second. A second ink supply path 43 connected to the ink reservoir 22, one end connected to the other ends of the first ink supply path 41 and the second ink supply path 43, and the other end connected to the recording head 9. A merging supply path 45 in which two liquids of the first ink liquid and the second ink liquid flow.
The ink supply path 15 configured as described above is configured to supply the first ink liquid supplied from the first ink storage unit 21 and the second ink liquid supplied from the second ink storage unit 22 to the merge supply path 45. The ink is mixed and stirred by the merging of the ink and supplied to the recording head 9 as ultraviolet curable ink.

  In the present embodiment, as shown in FIG. 2, the merging supply path 45 has a cylindrical housing 61 in which the first ink liquid and the second ink liquid flow and flows into the cylindrical housing 61. It functions as a static mixer including an element 63 that is fixedly mounted and causes the liquid flowing in the cylindrical housing 61 to change direction or to be divided.

As shown in FIG. 3, the element 63 has a structure in which twists that are reversed to each other are added to the liquid dividing plates 63a, 63b, 63c,. , 63b, 63c,..., By applying a new twist and division to the passing liquid, the passing liquid is uniformly mixed.
In FIG. 4A, the flow (twist) of each ink liquid on each liquid dividing plate 63a, 63b, 63c... Is indicated by an arrow.
4B shows a state in which the ink liquid passing through each of the liquid dividing plates 63a, 63b, 63c,...

  The specific number of liquid dividing plates 63a, 63b, 63c... In the element 63, the twisted state of each liquid dividing plate, the size and material of each liquid dividing plate, etc. can minimize the flow path loss. As described above, the design may be appropriately changed according to the physical properties of the first ink liquid and the second ink liquid.

  In the present embodiment, the first ink and the second ink are mixed and agitated in the merging supply path 45, so that at least a polymerization initiator and a polymerization compound are mixed at a predetermined ratio, and the one-component ultraviolet curing. Type ink. This ink can be cured by being irradiated with ultraviolet rays. It is preferable that ink is supplied from the ink storage units 21 and 22 to the merging supply path 45 by a necessary amount of ink ejected from the recording head 9.

  In the inkjet recording apparatus 1 described above, the ultraviolet curable ink is used in the apparatus as a reaction liquid containing a first ink liquid that is an ink composition containing a color material and a polymerization initiator. Because it is stored separately in two liquids with the ink liquid, it has the advantage of the two liquid type that can suppress changes in the physical properties of each ink liquid during storage, and storage of each ink liquid Since the stability is improved, stable printing performance can be maintained over a long period of time.

Further, in the ink jet recording apparatus 1 described above, the ink liquids stored in the ink storage units 21 and 22 that are independent from each other are initially stored in the first ink supply path 41 and the second ink supply path 43. The parts 21 and 22 are individually fed toward the recording head 9, and the respective ink liquids are mixed and stirred in the merged supply path 45 where the first ink supply path 41 and the second ink supply path 43 merge, The liquid is supplied to the recording head 9 as one liquid of ultraviolet curable ink generated by mixing the two liquids.
Therefore, it is possible to simplify and miniaturize the configuration of the recording head 9 by using a single ejection control mechanism incorporated in the recording head 9 for the ejection control of fine ink droplets even though it is a two-component type.

  In addition, the two liquids of the first ink liquid, which is an ink composition containing a coloring material, and the second ink liquid that contains a polymerization initiator and functions as a reaction liquid have a length of the merging supply path 45 and the like. Since sufficient mixing and agitation can be performed by setting appropriately, the two liquids are sufficiently compared with the conventional two liquid type in which the two liquids are mixed by contact with each other on the recording medium 7. By mixing and agitating, it is possible to prevent a partial drop in print quality due to non-uniform mixing, and to achieve high-quality and stable printing without printing unevenness.

  Furthermore, in the inkjet recording apparatus 1 of the present embodiment, the merged supply path 45 for mixing the two liquids is made to function as a static mixer so as to obtain a high mixing and stirring performance. By devising the shape and the like of the element 63, necessary and sufficient uniform mixing can be obtained even if the length of the merge supply path 45 is shortened, and the apparatus can be downsized by shortening the merge supply path 45. You can also.

Moreover, since the element 63 is a fixed equipment and there is no movable part, the static mixer can improve the cleanliness of the apparatus. Further, there is no malfunction due to wear of the movable part, and stable mixing and stirring performance can be maintained over a long period of time.
As the static mixer, 70 series, 85 series, 120 series, 140 series, etc. manufactured by Nippon Flow Control Co., Ltd. can be used.

  Hereinafter, “coloring material (pigment)”, “polymerization compound”, “polymerization initiator”, and “polymerization accelerator” contained in the first and second ink liquids of the present invention will be described in detail including specific examples thereof.

  It is preferable to use a pigment as the coloring material of the first ink liquid. Specific examples of the pigment include carbon black, No. 1 manufactured by Mitsubishi Chemical Corporation. 2300, no. 900, MCF88, No. 33, no. 40, no. 45, no. 52, MA7, MA8, MA100, no. 2200B, etc. are Raven 5750, 5250, 5000, 3500, 1255, 700, etc. made by Columbia, and Regal 400R, 330R, 660R, Mogu L, 700, Monarch 800, 880, 900, 1000, 1100, 1300, 1400, etc. are Degussa Color Black FW1, FW2, FW2V, FW18, FW200, Color Black S150, S160, S170, Printex. 35, U, V, 140U, Special Black 6, 5, 4A, 4 and the like.

Examples of pigments used in yellow ink include C.I. I. Pigment Yellow 1, 2, 3, 12, 13, 14, 16, 17, 73, 74, 75, 83, 93, 95, 97, 98, 109, 110, 114, 128, 129, 138, 150, 151, 154, 155, 180, 185 and the like.
Examples of pigments used for magenta ink include C.I. I. Pigment Red 5, 7, 12, 48 (Ca), 48 (Mn), 57 (Ca), 57: 1, 112, 122, 123, 168, 184, 202, 209, C.I. I. Pigment violet 19 and the like.
Further, examples of pigments used for cyan ink include C.I. I. And CI Pigment Blue 1, 2, 3, 15: 3, 15: 4, 60, 16, and 22.

  Although it does not specifically limit as a polymeric compound contained in the ink liquid of this invention, The monofunctional monomer, bifunctional monomer, polyfunctional monomer, and oligomer which are illustrated next are used.

(Monofunctional monomer)
(2-methyl-2-ethyl-1,3-dioxolan-4-yl) methyl acrylate, (2-methyl-2-isobutyl-1,3-dioxolan-4-yl) methyl acrylate, phenoxyethyl acrylate, isobol Nyl acrylate, N-vinylformamide, methoxydiethylene glycol monoacrylate, acroylmorpholine, lauryl methacrylate, allyl glycol, 2-hydroxyethyl methacrylate, cyclohexyl methacrylate, oxetane methacrylate, N-vinylcarbazole, N-vinylacetamide, N-vinyl pyrrolidone, N-vinyl caprolactam and the like.

(Bifunctional monomer)
Ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, tripropylene glycol diacrylate, 1,9-nonanediol diacrylate, polyethylene glycol # 400 diacrylate, tetraethylene glycol dimethacrylate, 1,6-hexane Diol diacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol diacrylate, neopentyl glycol dimethacrylate, 2-hydroxy-1,3-dimethacryloxypropane, hydroxypioperate ester neopentine glycol glycol diacrylate, etc. .

(Polyfunctional monomer)
Trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, trimethylolpropane EO adduct triacrylate, trimethylolpropane PO adduct triacrylate, glycerin EO adduct triacrylate, glycerin PO adduct triacrylate, pentaerythritol triacrylate , Dipentaerystol hexaacrylate, hydrogen phthalate- (2,2,2-triacroyloxymethyl) ethyl, dipentaerythritol polyacrylate and the like.

(Oligomer)
It is also called photopolymerizable prepolymer, base lysine or acrylic oligomer. For example, polyester acrylate, polyurethane acrylate, epoxy acrylate, polyether acrylate, oligo acrylate, alkyd acrylate, polyol acrylate, etc., depending on the molecular structure constituting the skeleton Can be mentioned.

  As a polymerization initiator (photopolymerization initiator) contained in the ink liquid of the present invention, for example, ultraviolet rays or visible light in a region of about 200 nm to 450 nm is absorbed to generate radicals or ions to start polymerization of the polymerizable compound. Typical examples of radical generation types are benzoin methyl ether, benzoin ethyl ether, isopropyl benzoin ether, isobutyl benzoin ether, 1-phenyl-1,2-propanedione-2- (o-ethoxy). Carbonyl) oxime, benzyl, diethoxyacetophenone, benzophenone, chlorothioxanthone, 2-chlorothioxanthone, isopropylthioxanthone, diethylthioxanthone, 2-methylthioxanthone, polychlorinated polyphenyl, hexachlorobenzene, etc. Preferably, isobutyl benzoin ether, 1-phenyl-1,2-propane-dione-2-(o-ethoxycarbonyl) oxime.

  Further, Vicure 10, 30 (manufactured by Stauffer Chemical), Irgacure 127, 184, 500, 651, 2959, 907, 369, 379, 754, 1700, 1800, 1850, 819, OXE01, Darocur 1173 (manufactured by Ciba Specialty Chemicals), Photopolymerization initiators available under the trade names Quantacure CTX, ITX (Aceto Chemical), Lucirin TPO (BASF), Kayacure DETX-S (Nippon Kayaku) and ESACURE KIP150 (Lamberti) are also used. can do.

The polymerization accelerator contained in the ink liquid of the present invention is preferably an amine compound. As the amine compound, an aminobenzoate derivative is particularly preferable because of the problem of odor and more reliable curing of the ink composition. This is because the aminobenzoate derivative reduces polymerization inhibition by oxygen.
The aminobenzoate derivative preferably has no absorption in the wavelength region of 350 nm or more. Examples of such aminobenzoate derivatives include ethyl-4-dimethylaminobenzoate, 2-ethylhexyl-4-dimethylaminobenzoate, etc., which are manufactured by Darocur EDB, EHA (manufactured by Ciba Specialty Chemicals). Available under the trade name.

Examples of other polymerization accelerators include fine particles having a polymerizable functional group. Although the mechanism of action of the fine particles having a polymerizable functional group is not clear, radicals generated by the cleavage of the polymerization initiator are adsorbed and stabilized on the surface of the fine particles, and the radicals are also easily adsorbed with monomers adsorbed on the fine particle surface. It is presumed that the reaction proceeds and the polymerization proceeds efficiently.
The fine particles having a polymerizable functional group are generally referred to as extender pigments, and examples thereof include inorganic compounds such as silica, alumina, titania, and calcium oxide. In particular, transparent ones such as silica and alumina are also suitable. Can be used for Moreover, examples of the polymerizable functional group possessed by the fine particles include an acryloyl group and a methacryloyl group, and a polymerizable functional group having one or more double bonds can also be used.

  Next, although the Example of this invention is given with a comparative example and this invention is demonstrated concretely, this invention is not limited by the following Examples.

[Examples and comparative examples]
In the following examples and comparative examples, “ink composition A” shown in the following [Table 2] is used as the first ink liquid, and “ink composition” shown in the following [Table 3] as the second ink liquid. Item B "was used.
In “ink compositions A and B”, “N-vinylformamide”, “tripropylene glycol diacrylate”, and “trimethylolpropane triacrylate” are used as “polymerization compounds”, and “polymerization initiator (photopolymerization initiator)” is used. "Irgacure 819: Bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, trade name of Ciba Specialty Chemicals" and "Irgacure 369: 2-benzyl-2-dimethylamine- 1- (4-Morpholinophenyl) butane-1 was also used under the trade name “Ciba Specialty Chemicals”. Further, “Darocur EHA: 2-ethylhexyl-4-dimethylaminobenzoate, trade name of Ciba Specialty Chemicals” was used as “polymerization accelerator”. The “dispersing agent” used in the ink composition A is a polyoxyalkylene polyalkylene polyamine.

(Print test)
Using PX-G900 (manufactured by Seiko Epson Corporation), the ink compositions A and B were cured on the medium with an ultraviolet irradiation device provided at the paper discharge port.
In the examples, the ink compositions A and B were joined and mixed in the joining supply path 45 using the ink jet recording apparatus of FIG. 1, and the resulting mixed ink composition was filled in the recording head 9 for printing. That is, for each of the Bk, C, M, and Y color ink compositions A shown in Table 2, the ink composition B shown in Table 3 is prepared, and the merge supply path 45 (the Japanese flow in the merge supply path 45) is prepared. Ink compositions A and B were combined and mixed in a static mixer (70 series: No. 070-317) manufactured by Control Co., and finally filled in the recording head 9 for printing.
On the other hand, in the comparative example, the ink compositions A and B were filled in another nozzle row, mixed on the medium, and printed.

(Evaluation of printing test)
In the examples, since the image was formed with the ink composition mixed and stirred, a clear image could be formed without causing variations in the curing reaction or color unevenness. On the other hand, in the comparative example, the printing reaction was partially deteriorated due to variations in the curing reaction as a whole or color unevenness.

1 is a perspective view showing a schematic configuration of an embodiment of an ink jet recording apparatus according to the present invention. FIG. 2 is a horizontal sectional view of a merging supply path shown in part A of FIG. 1. It is structure explanatory drawing of the element which comprises a static mixer in the confluence | merging supply path shown in FIG. FIG. 4 is an explanatory diagram of an operation process in which the two liquids that have joined in the element shown in FIG. 3 are uniformly mixed by repetition of division, and (a) shows the flow (twist) of each ink liquid on each liquid dividing plate of the element. Explanatory drawing (b) has shown the mode that the agitation advances as the division of the ink liquid passing through becomes fine every time it passes through each liquid dividing plate.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Inkjet recording device 7 Recording medium 9 Recording head 11 Carriage 13 Recording medium conveyance mechanism 15 Ink supply path 21 1st ink storage part 22 2nd ink storage part 41 1st ink supply path 43 2nd ink supply path 45 Merge supply path 61 Cylindrical housing 63 Element 63a, 63b, 63c ... Liquid partition plate

Claims (4)

A first ink reservoir for storing a first ink liquid;
A second ink reservoir that stores a second ink that produces ultraviolet curable ink by being mixed with the first ink;
A recording head for discharging the first ink liquid and the second ink liquid onto a recording medium;
An ink supply path for supplying ink liquid from each ink reservoir to the recording head;
An inkjet recording apparatus comprising: an ultraviolet irradiation unit configured to irradiate ultraviolet rays onto the recording medium on which the ultraviolet curable ink is applied by the recording head;
The ink supply path has a first ink supply path with one end connected to the first ink storage part, a second ink supply path with one end connected to the second ink storage part, and one end with the first and second ink supply paths. A confluence supply path connected to the other end of the second ink supply path and connected to the recording head at the other end to mix and stir the two liquids of the first ink liquid and the second ink liquid. Prepared,
The first ink liquid supplied from the first ink storage part and the second ink liquid supplied from the second ink storage part are mixed and agitated by joining together in the joint supply path, so that ultraviolet curable ink is obtained. An ink jet recording apparatus, wherein the ink jet recording apparatus is supplied to a recording head.   The merge supply path includes a cylindrical housing in which the first ink liquid and the second ink liquid merge and flow, and a direction change to a liquid that is fixedly installed in the cylindrical housing and flows in the cylindrical housing. The ink jet recording apparatus according to claim 1, wherein the ink jet recording apparatus is a static mixer including an element that causes division.   The first ink liquid is an ink liquid including at least a color material, and further includes a polymerization accelerator and / or a polymerization compound or a polymerization initiator, and the second ink liquid does not include a color material. The ink jet recording apparatus according to claim 1, wherein the ink recording liquid comprises a polymerization compound, a polymerization initiator, and / or a polymerization accelerator.   4. The ink jet recording apparatus according to claim 3, wherein the color material of the first ink liquid is a pigment.

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