WO2006092930A1

WO2006092930A1 - Image recording device and image recording method

Info

Publication number: WO2006092930A1
Application number: PCT/JP2006/301966
Authority: WO
Inventors: Wataru Ishikawa
Original assignee: Konica Minolta Medical & Graphic, Inc.
Priority date: 2005-03-01
Filing date: 2006-02-06
Publication date: 2006-09-08
Also published as: JPWO2006092930A1

Abstract

To enhance an image quality by preventing the non-uniformity of an image recorded with photo-curing ink. This image recording device comprises a recording head for recording an image by jetting photo-curing ink onto a recording medium, and a pair of light irradiation units for curing ink by applying a ultraviolet ray to ink landed on a recording medium. The image recording device comprises recording heads arranged along a scanning direction perpendicularly crossing the carrying direction of a recording medium held between recording heads and a carriage mounting thereon a pair of light irradiation units for reciprocatingly scanning in a scanning direction. A total of ink jetting amounts within a reference range on a go travel and on a return travel during carriage reciprocating operations is constant, and a ultraviolet ray is applied by a light irradiation unit to ink landed on a recording medium at the same timing on a go travel and on a return travel.

Description

Specification

Image recording apparatus and image recording method

Technical field

The present invention relates to an image recording apparatus and an image recording method, and more particularly to an image recording apparatus and an image recording method for recording an image using photocurable ink.

Background art

[0002] In an image recording apparatus such as an ink jet printer that records an image by discharging ink! In the meantime, an ink jet printer that records an image using a photocurable ink has been developed. By using photocurable ink, the photocurable ink can be hardened by irradiating light after image recording, making it difficult to erase the recorded image over a long period of time, and when the recorded image is placed outdoors. Excellent weather resistance can be exhibited even if it is awkward (see, for example, Patent Document 1)

In such an image recording apparatus, the recording medium is intermittently conveyed, and the recording head is not scanned in the scanning direction orthogonal to the conveying direction in accordance with the timing when the recording medium stops. There is a serial type image recording apparatus that discharges water. In a serial type image recording apparatus, a plurality of recording heads that eject inks of different colors are arranged along the scanning direction, and a pair of light irradiation devices are arranged so as to sandwich all the recording heads. ing. For this reason, even if the recording head ejects ink while reciprocating in the scanning direction, the light irradiation device can always irradiate the ink landed on the recording medium immediately after passing the recording head! / RU

Patent Document 1: Japanese Patent Laid-Open No. 2003-55449

Disclosure of the invention

Problems to be solved by the invention

By the way, when an image is recorded with water-based ink, the ink is absorbed by the recording medium. As described above, when an image is recorded using the photocurable ink, the ink is cured without being absorbed on the recording medium. For this reason, the surface becomes uneven and tends to be uneven. In particular, when a plurality of recording heads are arranged along the scanning direction, a pair of light irradiators from each recording head. The distance to each device is different. As a result, when ink is ejected while the recording head is reciprocated in the scanning direction, the timing at which the ink on the recording medium is irradiated with light differs between the forward pass and the return pass, and image quality unevenness may be emphasized. was there.

An object of the present invention is to improve image quality by suppressing unevenness of an image recorded with a photocurable ink.

Means for solving the problem

[0006] The image recording apparatus according to the invention of claim 1

A recording head for recording an image by discharging photocurable ink onto the recording medium; and an irradiation unit for irradiating the recording medium with ultraviolet rays. The ultraviolet rays from the irradiation unit are applied to the recording medium. A pair of light irradiation devices that cure the ink by irradiating the landed ink; and

A carriage that carries the recording head and the pair of light irradiation devices arranged along a scanning direction orthogonal to the conveyance direction of the recording medium so as to sandwich the recording head, and that reciprocates in the scanning direction; ,

A control unit that controls the recording head, the light irradiation device, and the carriage.

In the reciprocating operation of the carriage, the total amount of ink discharged with respect to the reference range during the forward path and during the backward path is constant, and the ultraviolet irradiation timing of the light irradiation device with respect to the ink landed on the recording medium during the forward path and the backward path The recording head, the light irradiation device, and the carriage are controlled so that they are the same.

According to the invention described in claim 1, since the total amount of ink discharged with respect to the reference range during the forward path and during the backward path in the reciprocating operation of the carriage is constant, one return / return is performed within the reference range. As a result, the total amount of ink landed becomes uniform. Further, since the ultraviolet irradiation timing of the light irradiation device with respect to the ink landed on the recording medium during the forward path and the backward path is the same, the ink landed during the forward path and the ink landed during the backward path can be cured at the same timing. . In other words, it is possible to irradiate ultraviolet rays at the same timing both during the forward pass and during the return pass while preventing the total amount of ink in the reference range from being different for each reciprocating operation. In addition, image quality unevenness can be suppressed.

[0008] The invention described in claim 2 is the image recording apparatus described in claim 1,

In the carriage, a plurality of the recording heads are arranged from the center to both side ends in the interval between the pair of light irradiation devices, and

Among the plurality of recording heads arranged between one end of the central force, the irradiation of one light irradiation device of the pair of light irradiation devices from the Nth (N is a natural number) recording head from the center. And from the Nth recording head among the plurality of recording heads arranged between the center and the other end, the second light irradiation device of the pair of light irradiation devices The pair of light irradiation devices are arranged so that the distance to the irradiation unit is the same.

[0009] According to the invention of claim 2, the number N (N is a natural number) from the center among the plurality of recording heads arranged between the center and one side end in the interval between the pair of light irradiation devices. The distance from the recording head of the eye to the irradiation part of one light irradiation device, and the plurality of recording heads arranged between the center and the other end of the light irradiation device from the Nth recording head from the center to the other light irradiation device Since the distance to the irradiation part is the same, the central force is also ejected by the Nth recording head that is ejected by the Nth recording head between the one end and the Nth recording head that is disposed between the other end from the center. The landed ink faces the irradiation section at the same timing. Thereby, the ultraviolet irradiation timing can be made the same at the time of the outward trip and at the time of the return trip while the ultraviolet ray is irradiated from the irradiation unit.

[0010] The invention described in claim 3 is the image recording apparatus described in claim 2,

The plurality of recording heads are arranged in a plurality of steps so as to be stepped,

The irradiation unit of one light irradiation device of the pair of light irradiation devices from the Nth recording head among the plurality of recording heads arranged between one end from the center for each stage. And the irradiation of the other light irradiation device of the pair of light irradiation devices from the Nth recording head among the plurality of recording heads arranged between the center and the other end. The pair of light irradiations so that the distance to the part is the same It is characterized by the fact that the device is arranged.

[0011] According to the invention of claim 3, even when a plurality of recording heads are arranged in a plurality of steps, a plurality of recording heads arranged between one end of the central force are provided for each step. Among the recording heads, the distance from the Nth recording head from the center to the irradiation part of one light irradiation device and the Nth recording head from the center among the recording heads arranged between the center and the other end Since the force is the same as the distance to the irradiation part of the other light irradiation device, the same action and effect as the invention of claim 2 can be obtained.

[0012] The invention described in claim 4 is the image recording apparatus described in claim 2,

The plurality of recording heads are disposed so as to be inclined with respect to the transport direction, and the pair of the pair of the recording heads disposed between one end of the central force from the Nth recording head from the center. Among the plurality of recording heads arranged between the center and the other end, from the Nth recording head from the center, the distance to the irradiation part of one of the light irradiation devices The irradiation unit of the pair of light irradiation devices is inclined with respect to the transport direction so that the distance to the irradiation unit of the other light irradiation device of the pair of light irradiation devices is the same. It is characterized by that.

According to the invention described in claim 4, even when the plurality of recording heads are arranged to be inclined with respect to the transport direction, the plurality of recordings arranged between the one ends of the central force. Among the heads, the distance from the Nth recording head from the center to the irradiation part of one light irradiation device and the Nth recording head from the center among the recording heads arranged between the center and the other end Since the irradiation unit of the pair of light irradiation devices is inclined with respect to the transport direction so that the distance to the irradiation unit of the other light irradiation device is the same, the same as the invention of claim 2 It is possible to obtain the actions and effects.

[0014] The invention according to claim 5 is the image recording apparatus according to any one of claims 2 to 4,

The ink colors ejected by the plurality of recording heads are set so that the arrangement order from one end to the center and the arrangement order between the other ends of the central force are the same with respect to the center. , Characterized by that! / [0015] According to the invention of claim 5, the ink colors ejected by the plurality of recording heads are arranged in the order of arrangement from the center to one side and the order of arrangement from the center force to the other side. Since they are set to be the same with respect to the center, the recording heads other than the recording head arranged in the center eject ink of the same color by the two recording heads. Of these two recording heads, the distance from one recording head to the irradiation part of one light irradiation device is the same as the distance from the other recording head to the irradiation part of the other light irradiation device. Therefore, the same color ink ejected from these two recording heads can be hardened at the same ultraviolet irradiation timing.

[0016] The invention described in claim 6

An image recording method for recording an image by ejecting photocurable ink from a recording head onto a recording medium, and curing the ink by irradiating the ink landed on the recording medium with a pair of light irradiation devices.ぉ

The recording head and the pair of light irradiation devices reciprocally scan in the scanning direction in a state of being arranged along a scanning direction orthogonal to the conveyance direction of the recording medium so as to sandwich the recording head.

In the reciprocating operation of the carriage, the total amount of ink discharged with respect to the reference range during the forward path and during the backward path is constant, and the ultraviolet irradiation timing of the light irradiation device with respect to the ink landed on the recording medium during the forward path and the backward path Are the same

[0017] According to the invention as set forth in claim 6, it is possible to obtain operations and effects equivalent to those of the invention as set forth in claim 1.

[0018] The invention according to claim 7 is the image recording method according to claim 6,

Among the plurality of recording heads arranged between one end of the central force, the irradiation unit of one of the pair of light irradiation devices from the Nth (N is a natural number) recording head from the center. And a plurality of the recordings arranged between the center and the other end. The pair of light irradiating devices is arranged so that the distance from the Nth recording head in the center to the irradiating part of the other light irradiating device of the pair of light emitting devices is the same. It is characterized by being arranged.

According to the invention described in claim 7, the same operation and effect as the invention described in claim 2 can be obtained.

[0020] The invention described in claim 8 is directed to the image recording method described in claim 7,

The irradiation unit of one light irradiation device of the pair of light irradiation devices from the Nth recording head among the plurality of recording heads arranged between one end from the center for each stage. And the irradiation of the other light irradiation device of the pair of light irradiation devices from the Nth recording head among the plurality of recording heads arranged between the center and the other end. The pair of light irradiating devices are arranged so that the distance to the unit is the same.

[0021] According to the invention as set forth in claim 8, it is possible to obtain the same operation and effect as the invention as set forth in claim 3.

[0022] The invention according to claim 9 is the image recording method according to claim 7,

[0023] According to the invention described in claim 9, the same operation and effect as the invention described in claim 4 can be obtained.

[0024] The invention according to claim 10 is described in any one of claims 7 to 9. For the image recording method described in this article,

The ink colors ejected by the plurality of recording heads are set so that the arrangement order from one end to the center and the arrangement order between the other ends of the central force are the same with respect to the center. , Characterized by that! /

[0025] According to the invention described in claim 10, it is possible to obtain the same operation and effect as the invention described in claim 5.

The invention's effect

[0026] According to the present invention, it is possible to irradiate ultraviolet rays at the same timing both during the forward pass and during the return pass while preventing the total amount of ink in the reference range from being different for each reciprocating operation. Can be suppressed.

Brief Description of Drawings

FIG. 1 is an explanatory diagram showing a schematic configuration of an image recording apparatus according to a first embodiment, (a) is a perspective view, and (b) is a bottom view.

2 is a block diagram showing a main control configuration of the image recording apparatus in FIG.

FIG. 3 is a bottom view showing a schematic configuration of a carriage provided in an image recording apparatus according to a second embodiment.

FIG. 4 is a bottom view showing a schematic configuration of a carriage provided in an image recording apparatus according to a third embodiment.

FIG. 5 is a bottom view showing a schematic configuration of a carriage provided in an image recording apparatus according to a fourth embodiment.

Explanation of symbols

[0028] 1 image recording apparatus

2 Carriage

31, 32, 33, 34 Recording head

41, 42 Light irradiation device

43 Filter (irradiation part)

BEST MODE FOR CARRYING OUT THE INVENTION [0029] [First embodiment]

The image recording apparatus according to the first embodiment will be described below with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples. FIG. 1 is a schematic configuration diagram showing a schematic configuration of the image recording apparatus.

[0030] The image recording apparatus 1 is an ink jet printer to which a serial method is applied. The image recording apparatus 1 includes a platen 6 that supports a recording medium P from below as shown in FIG. , A transport device 14 (see FIG. 2) for transporting the recording medium P on the platen 6 along the transport direction X, and a scan perpendicular to the transport direction X above the recording medium P transported by the transport device 14. A carriage 2 that reciprocates in the direction Y is provided.

In the carriage 2, a plurality of recording heads 31, 32, 33, 34 that discharge photocurable ink onto the recording medium P are arranged at equal intervals along the scanning direction Y. These recording heads 31, 32, 33, 34 are connected to the recording medium from the discharge port by the operation of the discharge means (not shown) provided with a plurality of inks of each color supplied by the ink supply means (not shown). Ink is discharged toward P. Of the plurality of recording heads 31, 32, 33, 34, the recording heads 31, 34 located on the outer side and the recording heads 32, 33 located on the inner side are each in pairs. Each of the recording heads 31, 32, 33, and 34 in the set discharges ink into the same reference range on the recording medium P! /.

[0032] On both sides of the carriage 2, a pair of light irradiation devices 41 and 42 that irradiate light onto the ink landed on the recording medium P to cure the ink sandwich the recording heads 31, 32, 33, and 34. In synchronization with the scanning of the carriage 2, the recording medium P is moved in the scanning direction Y. FIG. 1 (b) is a bottom view of the carriage 2 and the light irradiation devices 41 and 42. As shown in FIG. 1 (b), the light irradiation devices 41 and 42 are irradiated with ultraviolet rays toward the recording medium P. In addition, an ultraviolet light source that emits ultraviolet light in a specific wavelength region with stable exposure energy and a filter (irradiation unit) 43 that transmits ultraviolet light of a specific wavelength are provided. In other words, ultraviolet light is not transmitted from portions other than the filter 43. Here, mercury lamps, metal nitride lamps, excimer lasers, ultraviolet lasers, cold cathode tubes, hot cathode tubes, black lights, LEDs (Light Emitting Diodes), etc. can be applied as ultraviolet light sources. Metal halide lamp, cold cathode tube, hot cathode tube, mercury lamp Prefers black light ヽ. In particular, low pressure mercury lamps that emit ultraviolet light with a wavelength of 254 nm, hot cathode tubes, cold cathode tubes, and germicidal lamps are preferred because they can prevent bleeding and control dot diameter efficiently.

Here, the positional relationship between the pair of light irradiation devices 41, 42 and the recording heads 31, 32, 33, 34 will be described. The plurality of recording heads 31, 32, 33, and 34 are arranged between the center A and both side ends in the distance between the filters 43 of the pair of light irradiation devices 41 and 42. Specifically, the recording heads 31 and 32 are disposed between one end from the center A, and the recording heads 33 and 34 are disposed between the other end. If the recording heads 32 and 33 positioned first from the center A toward both ends are set as the first set, and the recording heads 31 and 34 positioned second are set as the second set, The distance A1 from the filter 43 of the light irradiation device 41 to the recording head 32 closer to the light irradiation device 41 and from the filter 43 of the other light irradiation device 42 to the recording head 33 closer to the light irradiation device 42 The interval A2 is set to be the same.

In the second set, the distance A3 from the filter 43 of one light irradiation device 41 to the recording head 31 closer to the light irradiation device 41 and the filter 43 of the other light irradiation device 42 The distance A4 to the recording head 34 closer to the light irradiation device 42 is set to be the same.

That is, among the plurality of recording heads 31 and 32 disposed between one end from the center A, the N-th recording head 31 and 32 from the center A (N is a natural number) of the one light irradiation device 41 The distances A1 and A3 to the filter 43 and the Nth recording head 33, 34 from the center A among the plurality of recording heads 33, 34 arranged between the center A and the other end, the other light irradiation device 42 A pair of light irradiation devices 41 and 42 are arranged so that the distances A2 and A4 to the filter 43 are the same.

FIG. 2 is a block diagram showing the main control unit of the image recording apparatus 1. As shown in FIG. 2, the image recording apparatus 1 is provided with a control unit 10 that controls each drive unit. The control unit 10 includes an input unit 11 for inputting various instructions such as an image recording start instruction, a carriage drive source 12 for driving the carriage 2, a storage unit 13 for storing a control program and control data, and a conveyance unit. The device 14, the recording heads 31, 32, 33, 34 and the light irradiation devices 41, 42 are electrically connected. In addition to these, the control unit 10 includes each drive unit of the image recording apparatus 1 and the like. Is connected. The control unit 10 controls various devices according to the control program and control data in the storage unit 13.

Next, the photocurable ink will be described.

[0038] In particular, the photo-curing ink is based on "Photo-curing system (Chapter 4)" described in "Photo-curing technology-Selection of resin / initiator and measurement of blending conditions and degree of cure" The ink is compatible with “Curing systems that use photoacid base generators (Section 1)” and “Light-induced alternating copolymerization (Section 2)”. This photo-curable ink is composed of a coloring material, a polymerizable monomer, a photoinitiator, etc., and undergoes monomer crosslinking and polymerization reaction when the photoinitiator acts as a catalyst when irradiated with light. It has the property of being cured by. However, the photoinitiator may be excluded when an ink that conforms to the above-mentioned “light-induced alternating copolymerization (section 2)” is used as the photocurable ink used in the present embodiment.

[0039] Photocurable inks are largely classified into radical polymerization inks containing radical polymerizable monomers and cationic polymerization inks containing cationic polymerizable monomers as polymerizable compounds, and there is little inhibition of polymerization reaction by oxygen. In addition, the cationic polymerization ink having no or higher properties is superior in functionality and versatility, so that the cationic polymerization ink is preferably used.

[0040] The radical polymerizable monomer is a compound having an ethylenically unsaturated bond capable of radical polymerization and any compound having at least one ethylenically unsaturated bond capable of radical polymerization in the molecule. Those with chemical forms such as monomers, oligomers and polymers are included. Only one type of radically polymerizable monomer may be used, or two or more types may be used in combination at an arbitrary ratio in order to improve the desired properties.

[0041] Examples of compounds having an ethylenically unsaturated bond capable of radical polymerization include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, and salts and esters thereof. , Urethane, amide anhydride, acrylonitrile, styrene, and various radically polymerizable compounds such as various unsaturated polyesters, unsaturated polyethers, unsaturated polyamides, and unsaturated urethanes. Specifically, 2-ethyl hexyl acrylate, 2-hydroxyethyl acrylate, butoxycheyl acrylate, carbitol acrylate, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, benzyl acrylate, bis ( 4-Atalyloxypolyethoxyphenyl) propane, neopentyl Recall diatalylate, 1, 6 hexanediol diatalate, ethylene glycol diatalate, diethylene glycol diatalate, triethylene glycol diatalate, tetraethylene glycol diatalate, polyethylene glycol diatalate, polypropylene glycol diataliate , Pentaerythritol Triatalylate, Pentaerythritol Tetratalylate, Dipentaerythritol Tetratalylate, Trimethylol Propane Tritalylate, Tetramethylol Methane Tetraacrylate, Oligoesterolacrylate, N-Methylolacrylamide, Diacetone Acrylic acid derivatives such as acrylamide and epoxy acrylate, methyl methacrylate, n-butyl methacrylate 2-Ethylhexyl methacrylate, lauryl methacrylate, allyl methacrylate, glycidino methacrylate, benzyl methacrylate, dimethylaminomethyl methacrylate, 1, 6 hexanedimethacrylate , Ethylene glycolonoresimethacrylate, triethyleneglyconoresimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, trimethylol ethane trimethacrylate, trimethylolpropane trimethacrylate, 2,2bis (4-methacrylate) Roxypolyethoxyphenol) Methacryl derivatives such as propane, and other derivatives of aryl compounds such as allyl glycidyl ether, diallyl phthalate, triallyl trimellitate, and more specifically, Yamashita Three editions, “Crosslinking agent handbook” (1981 Taiseisha); Kato Kiyomi edition, “UV'EB curing handbook (raw material edition)” (1985, Polymer publication society); Radtech study group edition, “UV ' Application and Market of EB Curing Technology ”, 79 page, (1989, C.I.M.); Eiichiro Takiyama,“ Polyester Liquor Handbook ”, (1 988, Nikkan Kogyo Shimbun) And known radically polymerizable or crosslinkable monomers, oligomers and polymers can be used. The amount of the radically polymerizable compound added is preferably 1 to 97% by mass, more preferably 30 to 95% by mass.

Examples of the radical polymerization initiator include triazine derivatives described in JP-B-59-1281, JP-A-69-1621, and JP-A-60-60104, JP-A-59-1504 and JP-A-61-243807. And other publications such as JP-B-43-23684, JP-B-44 6413, JP-B-44-6413 and JP-B-47-1604, and U.S. Pat. No. 3,567,453. No. 2, 848, 328, the same Organic azide compounds described in the respective specifications of 2,852,379 and 2,940,853, JP-B 36-22062, 37-13109, 38-18015, 45-9610 Ortho-quinonediazides described in each publication such as No. 55-39162, JP-A-59-14023, etc., and “Macromolecules (10th and 1307)”. Di- (1977), various azo compounds described in JP-A-59-142205, JP-A-1 54440, Cyono-Juno Patent No. 109,851, Nos. 126, 712, etc., “Journal 'Ob' Imaging 'Science'” (J. Imag. Sci.), Pp. 30 and 174 (1986); (Oxo) sulfo-um organoboron complexes described in each of publications 4-213861 and 4-255347, titanocenes described in JP-A-61-151197, “cordine” Transition metal complexes containing transition metals such as ruthenium described in "Coordination Chemistry Review", No. 84, No. 85, No. 277 (1988) and JP-A-2-182701. 2, 4, 5 triaryl imidazole dimers described in JP-A-3-209477, carbon tetrabromide, and organic halogen compounds described in JP-A-59-107344. These polymerization initiators are preferably contained in the range of 0.01 to 10 parts by mass with respect to 100 parts by mass of the compound having an ethylene unsaturated bond capable of radical polymerization.

[0043] The compound having an oxetane ring according to the present invention will be described.

[0044] (Oxetane compound substituted at the 2-position and having a oxetane ring)

In the actinic ray curable composition, it is preferable to use an oxetane compound having at least one oxetane ring substituted in the 2-position represented by the following general formula (1) in the molecule.

[0045] [Chemical 1]

—General formula (1)

In the above general formula (1), R1 to R6 each represent a hydrogen atom or a substituent. However, at least one of the groups represented by R 3 -R6 is a substituent. In general formula (1), R1—R Examples of the substituent represented by 6 include a fluorine atom, an alkyl group having 16 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, or a butyl group), and a 16-carbon fluoroalkyl group. A group, a aryl group, an aryl group (for example, a phenyl group, a naphthyl group, etc.), a furyl group, or a phenyl group. Moreover, these groups may further have a substituent.

[0047] (Oxetane compound having one oxetane ring in the molecule)

Further, among the above general formula (1), compounds having an oxetane ring represented by the following general formulas (2) to (5) are preferably used.

[0048] [Chemical 2]

General formula (2)

General formula (3)

-General formula (4)

[0049] In the formula, Rl-R6 represents a hydrogen atom or a substituent, R7 and R8 each represent a substituent, and Z each independently represents an oxygen or sulfur atom, or contains an oxygen or sulfur atom in the main chain. Represents a divalent hydrocarbon group. In the general formula (2)-(5), the substituent represented by R1-R6 has the same meaning as the substituent represented by R1-R6 in the general formula (1).

[0050] In the general formula (2)-(5), the substituent represented by R7 or R8 is an alkyl group having 1 to 6 carbon atoms (for example, a methyl group, an ethyl group, a propyl group or a butyl group) ), Carbon number 1 6 alkell groups (eg 1 probe group, 2 probe group, 2-methyl-1 probe group, 2-methyl-2- probe group, 1-buture group, 2 —Butur group or 3-butenyl group, etc.), aryl group (eg, phenyl group, naphthyl group, etc.), aralkyl group (eg, benzyl group, fluorobenzoyl group, methoxybenzyl group, etc.), carbon number 1 6 acyl groups (for example, propyl carbonyl group, butyl carbo yl group or pentyl carbonyl group, etc.), 16 alkoxy carbonyl groups (for example, ethoxy carbo yl group, propoxy carbo yl group, Butoxycarbol group, etc.), C16 alkyl group rubamoyl group (for example, propyl group rubamoyl group, butylpentylcarbamoyl group, etc.), alkoxy group rubamoyl group (for example, ethoxycarbamoyl group, etc.) Represent.

[0051] In the general formulas (2) to (5), an oxygen or sulfur atom represented by Z, or may contain an oxygen or sulfur atom in the main chain. ヽ Divalent hydrocarbon Examples of the group include an alkylene group (for example, ethylene group, trimethylene group, tetramethylene group, propylene group, ethylethylene group, pentamethylene group, hexamethylene group, heptamethylene group, otatamethylene group, nonamethylene group, decamethylene group, etc.), Alkylene groups (for example, ethylene-groups, _3- pentylene-groups, etc.) and alkylene groups as described above. The carbon atom of the alkylene group or the alkylene group may be replaced with an oxygen atom or a sulfur atom.

[0052] Among the above substituents, R1 is preferably a lower alkyl group (for example, a methyl group, an ethyl group, a propyl group, etc.), and particularly preferably used is an ethyl group. R7 and R

8 is preferably a propyl group, a butyl group, a phenol group, or a benzyl group. Z is a hydrocarbon group containing no oxygen or sulfur atom (an alkylene group, an alkylene group, an alkylene group, etc.). preferable.

[0053] (compound having two or more oxetane rings in the molecule)

In the present invention, a compound having two or more oxetane rings in a molecule represented by the following general formulas (6) and (7) can be used.

[0054] [Chemical 3] —General formula (6)

General formula (7)

In the formula, Z has the same meaning as the group used in the general formulas (2) to (5), and m represents 2, 3 or 4. R1-R6 is a hydrogen atom, a fluorine atom, an alkyl group having 16 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, a butyl group, etc.), a fluoroalkyl group having 16 carbon atoms, an aryl group, an aryl group. Represents a group (for example, a phenyl group, a naphthyl group, etc.) or a furyl group. However, in the general formula (6), at least one of R3-R6 is a substituent.

[0056] In the formula, R9 is a linear or branched alkylene group having 1 to 12 carbon atoms, a linear or branched poly (alkyloxy) group, or a group force selected from the following general formulas (9), (10), and (11) Represents a divalent group.

[0057] As an example of the branched alkylene group having 112 carbon atoms, an alkylene group represented by the following general formula (8) is preferably used.

[0058] [Chemical 4]

—General formula (8) —Shi !!

[0059] In the formula, R10 represents a lower alkyl group (eg, a methyl group, an ethyl group, a propyl group, etc.).

[0060] [Chemical 5]

-General formula (9)

l2

I I I

(CH,), — Si-0-(Si-0) „-Si— (CH ₂ ) _3- [0061] In the formula, n represents 0 or an integer of 1 to 2000, and R12 represents an alkyl group having 1 to 10 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group). R11 represents an alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, hexyl group, hexyl group, hexyl group, hexyl group, hexyl group, hexyl group, hexyl group, Represents a group represented by the following general formula (12).

[0062] [Chemical 6]

Formula (12) 1 0- (Si— 0) j-Si— (CH ₂ ) ₃

"13" 13

[0063] In the formula, j represents 0 or an integer of 1 to 100, and R13 represents an alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group) Group, heptyl group, octyl group, nonyl group, etc.).

[0064] [Chemical 7]

General formula (10>

[0065] In the formula, R14 represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group). Group), C 1-10 alkoxy group (for example, methoxy group, ethoxy group, propoxy group, butoxy group, pentoxy group, etc.), halogen atom (for example, fluorine atom, chlorine atom, bromine atom, iodine atom) Etc.), a nitro group, a cyano group, a mercapto group, an alkoxycarbonyl group (for example, a methyloxycarbonyl group, an ethoxycarbonyl group, a butoxy group sulfonyl group, etc.) or a carboxyl group.

[0066] [Chemical 8]

General formula (1 1)

[0067] In the formula, R15 represents an oxygen atom, a sulfur atom, —NH—, —SO—, —SO 1, —CH 1,

twenty two

C (CH) represents one or C (CF).

3 2 2 2

[0068] As a preferred partial structure of the compound having an oxetane ring used in the present invention, for example, in the above general formulas (6) and (7), R1 is a lower alkyl group (for example, a methyl group, Ethyl group, propyl group, etc.) are preferred, and ethyl group is particularly preferred. R9 is preferably a hexamethylene group or one in which R14 is a hydrogen atom in the general formula (10).

[0069] In the above general formula (8), R10 is an ethyl group, R12 and R13 are methyl groups, Z does not contain an oxygen or sulfur atom!

Furthermore, as an example of a preferred embodiment of the compound having an oxetane ring according to the present invention, a compound represented by the following general formula (13) can be mentioned.

[0071] [Chemical 9]

General formula (13>

[0072] In the formula, r is an integer of 25 to 200, and R16 represents an alkyl group having 1 to 4 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, a butyl group, etc.) or a trialkylsilyl group. . Rl, R3, R5, and R6 have the same meaning as the substituent represented by R1-R6 in the general formula (1). However, at least one of R3-R6 is a substituent.

Hereinafter, specific examples of the compound having an oxetane ring substituted at the 2-position according to the present invention will be shown as Exemplary Compound 1-15, but the present invention is not limited thereto.

[0074] 1: trans 3-tert-butyl 2-phenyloxetane

2: 3, 3, 4, 4-tetramethyl-2, 2 diphenyloxetane

3: Di [3 ethyl (2-methoxy-3-oxetal)] methyl ether

4: 1, 4 bis (2, 3, 4, 4-tetramethyl-3 ethyloxetal) butane 5: 1, 4 bis (3-methyl-3ethyloxeta-l) butane

6: Di (3,4,4 trimethyl-3-ethyloxetanyl) methyl ether

7: 3-((2-ethylhexyloxymethyl) -2,2,3,4-tetramethyloxetane 8: 2-(2-ethylhexyloxy) 2,3,3,4,4 pentamethylo Xetane 9: 4,4 '—bis [(2,4-dimethyl-3-ethyl-3-oxeta-methoxy) bi] bi-nore

10: 1, 7 bis (2, 3, 3, 4, 4 pentamethyloxetal) heptane)

11: Oxetanyl · Silsesquioxane

12: 2-Methoxy 3, 3 dimethyloxetane

13: 2, 2, 3, 3—tetramethyloxetane

14: 2- (4-Methoxyphenol) 3, 3 Dimethyloxetane

15: Di (2- (4-methoxyphenol) 3 methyloxetane 3yl) ether Synthesis of a compound having an oxetane ring substituted at least at the 2-position according to the present invention is synthesized with reference to the following documents: be able to.

(1) Hu Xianming, Richard M. Kellogg, Synthesis, 533— 538, May (19 95)

(2) A. O. Fitton, J. Hill, D. Ejane, R. Miller, Synth., 12, 1140 (1987)

(3) Tosniro Imai and Shinya Nishida, Can.

J. Chem. Vol. 59, 2503— 2509 (1981)

(4) Nobujiro Shimizu, Shintaro Yamaoka, and Yuho Tsuno, Bull.Ch em.Soc.Jpn., 56, 3853-3854 (1983)

(5) Walter Fisher and Cyril A. Grob, Helv. Chim. Acta., 61, 2336 (1 978)

(6) Chem. Ber. 101, 1850 (1968)

(7) "Heterocyclic Compounds with Three— and Four— membered Rings", Part Two, Chapter IX, Interscience Publishers, John Wiley & S ons, New York (1964)

(8) Bull. Chem. Soc. Jpn., 61, 1653 (1988) (9) Pure Appl. Chem., A29 (10), 915 (1992)

(10) Pure Appl. Chem., A30 (2 & 3), 189 (1993)

(11) JP 6-16804 A

(12) German Patent No. 1, 021, 858

The content of the compound having an oxetane ring substituted at least at the 2-position according to the present invention in the actinic ray curable ink is preferably 1 to 97% by mass, more preferably 30 to 95% by mass.

[0076] (Combination of oxetane compound and other monomer)

Further, the compound having an oxetane ring substituted at least at the 2-position according to the present invention may be used alone, or two kinds having different structures may be used in combination. Photopolymerizable compounds such as monomers and polymerizable monomers can be used in combination. When used in combination, it is preferable to prepare a compound having an oxetane ring substituted at least at the 2-position so that the compound is 10-98% by mass in the mixture, and other photopolymerizable monomers and polymerizable compounds. It is preferable to adjust the photopolymerizable compound such as monomer to 2 to 90% by mass.

[0077] (Oxetane compound having a substituent only at the 3-position)

In the present invention, an oxetane compound having a substituent only at the 3-position can be preferably used in combination with the above-described oxetane compound having a substituent at the 2-position and a conventionally known oxetane compound.

Here, as an oxetane compound having a substituent only at the 3-position, for example, JP-A-2001-2001

-Introduced in 220526, 2001-310937, the publicly known ones can be used.

[0079] Examples of the compound having a substituent only at the 3-position include compounds represented by the following general formula (14).

[0080] [Chemical 10]

—General formula (14)

[0081] In the general formula (14), R1 represents a hydrogen atom, a methyl group, an ethyl group, a propyl group, a butyl group, or the like, a C16 alkyl group, a C16 fluoroalkyl group, an aryl group, or an aryl group. , Furyl group or chael group. R2 is an alkyl group having 16 carbon atoms such as methyl group, ethyl group, propyl group, butyl group, 1 probe group, 2 probe group, 2-methyl-1 probe group, 2-methyl- 2-Propyl group, 1-Butul group, 2-Butul group, 3-Butul group, etc. C2-C6 alkenyl group, Phenol group, Benzyl group, Fluoro-benzyl group, Methoxy Groups having an aromatic ring such as benzyl group and phenoxychetyl group, alkylcarbonyl group having 2 to 6 carbon atoms such as ethylcarbol group, propylcarbol group and butylcarbol group, ethoxycarbol group, propoxy 2 to 6 carbon atoms such as a carbol group, butoxycarbol group, etc. 2 to 6 carbon atoms such as an alkoxycarbol group having 6 carbon atoms, an ethylcarbamoyl group, a propyl carbamoyl group, a butylcarbamoyl group or a pentylcarbamoyl group 6 N alkyl power Luba Moyl group and the like. As the oxetane compound used in the present invention, it is particularly preferable to use a compound having one oxetane ring because it has excellent adhesiveness, low viscosity and excellent workability.

[0082] An example of a compound having two oxetane rings includes a compound represented by the following general formula (15).

[0083] [Chemical 11]

'General

In general formula (15), R 1 is the same group as that in general formula (14). R3 is, for example, a linear or branched poly (alkylene group) such as a linear or branched alkylene group such as an ethylene group, a propylene group or a butylene group, a poly (ethyleneoxy) group or a poly (propyleneoxy) group. Xy) group, a probelene group, a methyl probelene group, a butylene group or other linear or branched unsaturated hydrocarbon group, an alkylene group containing a carbonyl group or a carbo yl group, a carboxyl group An alkylene group containing an alkyl group, an alkylene group containing a strong rubamoyl group, and the like.

[0085] Also, R3 may be selected from the groups represented by the following general formulas (16), (17) and (18). Valent groups.

[0086] [Chemical 12]

General formula (16)

[0087] In general formula (16), R4 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, or a butyl group, a methoxy group, an ethoxy group, or a propoxy group. A C14 alkoxy group such as a butoxy group, a halogen atom such as a chlorine atom or a bromine atom, a nitro group, a cyano group, a mercapto group, a lower alkoxy carbo group, a carboxyl group or a strong rubamoyl group. .

[0088] [Chemical 13]

—General formula 1 7>

[0089] In the general formula (17), R5 represents an oxygen atom, a sulfur atom, a methylene group, NH, SO, SO, C

2

Represents (CF) or C (CH).

3 2 3 2

[0090] [Chemical 14]

—General formula (18)

[0091] In the general formula (18), R6 is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, or a butyl group, or an aryl group. n is an integer between 0 and 2000. R7 is a methyl group, an ethyl group, a propyl group, a butyl group having a carbon number of 14 or an aryl group. As R7, a group selected by the basic force represented by the following general formula (19) can be mentioned.

[0092] [Chemical 15] —General formula (19>

8 R ⁸

, f _v I _Q

— O— fsi-o † — Si— R ⁸

, 1 ' ^m I

R ⁸ R ^s

In the general formula (19), R8 is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, a butyl group, or an aryl group. m is an integer from 0 to 100.

[0094] Specific examples of the compound having two oxetane rings include the following compounds.

[0095] [Chemical 16]

Illustrative compound 1 is a compound in which R1 is an ethyl group and R3 is a carboxyl group in the general formula (15). Exemplified Compound 2 is a compound in which R1 is an ethyl group, R3 is the general formula (18), R6 and R7 are methyl groups, and n is 1 in the general formula (15).

[0097] Among the compounds having two oxetane rings, preferred examples other than the above-mentioned compounds include compounds represented by the following general formula (20). In the general formula (20), R1 has the same meaning as R1 in the general formula (14).

[0098] [Chemical 17]

[0099] As an example of a compound having 3 to 4 oxetane rings, a compound represented by the following general formula (21) can be given.

[0100] [Chemical 18] (General formula 21)

[0101] In the general formula (21), R1 has the same meaning as R1 in the general formula (14). As R9, for example, a branched alkylene group having 1 to 12 carbon atoms such as a group represented by the following A to C, a branched poly (alkyleneoxy) group such as a group represented by the following D, or the following E And branched polyoxy groups such as those shown. j is 3 or 4.

[0102] [Chemical 19]

B

C

-CH ₂ — CH ₂ — CH—CH ₂ — CH— CH ₂ — CH ₂ —

D

CH3 CH3

_{_{- CH 2 -GH -CH 2 - Si-}} O- St-CH 2 - CH-CH 2 - - CH 2 CH 3 CH 3 CH 2 -

[0103] In the above A! /, RIO is a lower alkyl group such as a methyl group, an ethyl group or a propyl group. In D above, p is an integer of 1-10.

[0104] As an example of a compound having 3 to 4 oxetane rings, Exemplified Compound 3 may be mentioned.

[0105] [Chemical 20] Exemplary Compound 3

[0106] Furthermore, examples of the compound having 14 oxetane rings other than those described above include compounds represented by the following general formula (22).

[0107] [Chemical 21]

General formula (22)

In the general formula (22), R8 has the same meaning as R8 in the general formula (19). R11 is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group, or a trialkylsilyl group, and r is 14;

[0109] Preferable examples of the oxetane compound according to the present invention include the exemplified compounds 4, 5, and 6 shown below.

[0110] [Chemical 22]

Exemplary Compound 4

Exemplary Compound 5

Exemplary Compound 6

[0111] The production method of each compound having an oxetane ring described above is not particularly limited. For example, Pattyson (DB Pattison, J. Am. Chem. Soc., 3455, 79) can be used. (1957)) discloses a method for synthesizing an oxetane ring from a diol. In addition to these, compounds having 1 to 4 oxetane rings having a high molecular weight of about 1000 to 5000 are also included. Specific examples of these compounds include the following exemplified compounds 7, 8, and 9.

[0112] [Chemical 23]

Exemplary Compound 7

Exemplification

Example 9

[0113] As the epoxy compound according to the present invention, any of a monomer having an epoxy group and an oligomer thereof can be used. Specific examples include conventionally known aromatic epoxy compounds, alicyclic epoxy compounds, and aliphatic epoxy compounds. Hereinafter, the epoxy compound means a monomer or an oligomer thereof. As the oligomer in the present invention, an oligomer having a molecular weight of less than 1000 is preferred, and a low molecular weight compound is preferred.

[0114] A preferable aromatic epoxy compound is a di- or polyglycidyl produced by the reaction of a polyhydric phenol having at least one aromatic nucleus or an alkylene oxide adduct thereof and epichlorohydrin. Ether, for example, di- or polyglycidyl ether of bisphenol A or its alkylene oxide adduct, hydrogenated Examples thereof include di- or polyglycidyl ethers of bisphenol A or its alkylene oxide-containing case, and novolak-type epoxy resins. Here, examples of the alkylene oxide include ethylene oxide and propylene oxide.

[0115] As the alicyclic epoxy compound, at least one compound having a cycloalkane ring such as cyclohexene or cyclopentene ring is epoxyized with a suitable oxidizing agent such as hydrogen peroxide or peracid. Specific examples of preferred cyclohexene oxide or cyclopentene oxide-containing compounds obtained by the above include the following compounds.

[0116] Preferred examples of the aliphatic epoxy compound include di- or polyglycidyl ethers of aliphatic polyhydric alcohols or alkylene oxide adducts thereof, and typical examples thereof include diglycidyl ether of ethylene glycol, Polyglycerides such as diglycidyl ether of propylene glycol or diglycidyl ether of alkylene glycol such as diglycidyl ether of 1,6-hexanediol, di- or triglycidyl ether of glycerin or its alkylene oxide Polyglycidyl ether of alcohol, diglycidyl ether of polyethylene glycol or its alkylene oxide-attached case, polypropylene glycol or diglycidyl ether of its case containing alkylene oxide Diglycidyl ethers of sharpness glycol or the like can be mentioned, et al are. Here, examples of the alkylene oxide include ethylene oxide and propylene oxide.

[0117] Further, in addition to these compounds, monoglycidyl ethers of higher aliphatic alcohols and phenols, monoglycidyl ethers of cresol, etc., which are monomers having one oxolan ring in the molecule, may be used. it can. Of these epoxy compounds, aromatic epoxy compounds and alicyclic epoxy compounds are preferred in view of fast curing properties. Particularly preferred are alicyclic epoxy compounds. In the present invention, one of the above epoxy compounds may be used alone, or two or more may be used in appropriate combination.

[0118] The actinic ray curable composition of the present invention contains an epoxy fatty acid ester or an epoxy fatty acid glyceride as an epoxy compound.

[0119] Oxetane combination of epoxy fatty acid ester or epoxy fatty acid glyceride By using it in combination with the Z-cycloaliphatic epoxy compound system, AMES and the curing environment (temperature, humidity) that is preferable only from the viewpoint of safety 'environment such as sensitization, skin irritation, odor, etc. It can solve the problems of conventional strength such as generation of wrinkles due to curing shrinkage, poor curability and ejection properties.

[0120] The epoxy fatty acid ester and epoxidized fatty acid glyceride that can be used in the present invention are not particularly limited as long as an epoxy group is introduced into the fatty acid ester or fatty acid dalyceride.

[0121] The epoxy fatty acid ester is produced by epoxidizing an oleic acid ester, and therefore, methyl epoxy stearate, ptyl epoxy stearate, octyl epoxy stearate and the like are used. Similarly, epoxy fatty acid glyceride is produced by epoxidizing soybean oil, linseed oil, castor oil, etc., and epoxidized soybean oil, epoxidized linseed oil, epoxidized castor oil, etc. Used.

In the present invention, “does not generate benzene by actinic ray irradiation” means that benzene is not substantially generated. Specifically, an onium salt (photoacid generator) is contained in the ink composition. ) with 5 wt% containing ink and prints the images of about 100 m ² with a thickness 15 m, an active ray photoacid generators while maintaining the ink film surface 30 ° C is sufficient to decompose the amount of This means that the amount of benzene generated when irradiating is very little or less than 5 g. The o-um salt satisfies the above conditions as long as it has a substituent on the benzene ring that binds to S + or 1+, which is preferred to sulfo- or odonium salts.

[0123] The actinic ray curable ink of the present invention contains a pigment as a coloring material. The pigments that can be preferably used in the present invention are listed below.

[0124] C. I Pigment Yellow— 1, 3, 12, 13, 14, 17, 42, 74, 81, 83, 87, 93, 95, 109, 120, 128, 138, 139, 151, 166, 180 , 185

C. I Pigment Orange— 16, 36, 38

C. I Pigment Red—5, 22, 38, 48: 1, 48: 2, 48: 4, 49: 1, 53: 1, 57: 1, 63: 1, 101, 122, 144, 146, 177 , 185

C. I Pigment Violet—19, 23

C. I Pigment Blue—15: 1, 15: 3, 15: 4, 18, 60, 27, 29 C. I Pigment Green—7, 36

C. I Pigment White—6, 18, 21

C. I Pigment Black— 7

For the dispersion of the pigment, for example, a ball mill, sand mill, attritor, roll mill, agitator, Henschel mixer, colloid mill, ultrasonic homogenizer, pearl mill, wet jet mill, paint shaker, or the like can be used. The dispersion medium is a photopolymerizable compound. Among them, the monomer having the lowest viscosity is preferred for dispersion suitability.

[0125] For the dispersion of the pigment, it is preferable that the average particle size of the pigment particles is 0.08-0.5 μm. The maximum particle size is 0.3-lO ^ m, preferably 0.3-3 m. The pigment, dispersant, and dispersion medium should be selected, and the dispersion conditions and filtration conditions should be set appropriately. By controlling the particle size, clogging of the head nozzle can be suppressed, and ink storage stability, ink transparency, and curing sensitivity can be maintained.

[0126] In the photocurable ink, the colorant concentration is preferably 1% by mass to 10% by mass of the whole ink! /.

[0127] As the pigment dispersant, a polymer dispersant having a basic anchor portion is preferably used, and a polymer dispersant having a shape structure is more preferably used.

[0128] Specific examples of the pigment dispersant that can be used in the present invention include Solverse 9000, 17000, 18000, 19000, 19000, 20000, 24000SC, 24000 GR, 28000, and the same manufactured by Avecia. 32000, Ajinomoto Fine Technone Ajisunoichi PB821, PB822, Enomoto Kasei PLAAD ED214, ED251, DISPARLON DA-325, DA-234, EFKA EFKA-5207, 5244, 6220, 6225 It is mentioned with equal power. In addition, pigment derivatives (synergists) that can be used in combination with pigment dispersants include the following examples of pigment derivatives: Avecia Sonoreth Noose 5000, 12000, 22000, EF KA EFKA-6746 6750 etc.

[0129] The actinic ray curable composition of the present invention contains 4 to 10-membered aliphatic cyclic ester compound or 5 or more-membered cyclic ether compound, so that the composition has good curability and high density to various substrates. This is preferable because the wearability is improved.

[0130] The cyclic ester compound is a 4- to 10-membered aliphatic cyclic ester compound. Specifically, ε-strength prolatatone-6 hydroxyhexanoic acid 1,6-latataton, β-propilatatataton, 13 butyrolatathone, (X-methinolet β-butyrolatatane, γ-butyrolacton, Ί valerolatataton, δ valerolatatone, ε-strength prolatathone, γ-force prolatatone, γ-heptanolataton, coumarin, tetronic acid, pyrone, phthalide, 3-methyl-1,4 dioxer 2,5 dione, ρ dioxanone, morpholinedione, morpholine. A mixture thereof may be used.

[0131] The cyclic etheric compound is a five-membered or higher cyclic etheric compound. More preferably, it is a cyclic ether compound having no carbonate ester structure. Specifically, 1,3-dioxolane, tetrahydrofuran, 1,4 dioxane, 1, 3,5 trioxane, crown ether (12-crown-4, etc.), 1,2 dimethyltetrahydrofuran, 2-methyltetrahydrofuran, 2-methyl Dioxolan, 4-methyldioxolane, etc.

[0132] The content of the 4-membered aliphatic cyclic ester compound and the 5-membered or higher cyclic ether compound is preferably 110% by mass.

[0133] Various additives other than those described above can be used in the actinic ray curable composition of the present invention. For example, surfactants, leveling additives, matting agents, polyester-based resins, polyurethane-based resins, bull-based resins, acrylic-based resins, rubber-based resins, waxes for adjusting film properties Can be added. In addition, for the purpose of improving storage stability, any known basic compound can be used. Typical examples include basic alkali metal compounds, basic alkaline earth metal compounds, and amines. Organic organic compounds. Further, it is also possible to use a radical cation-free, hybrid type cured ink.

[0134] A basic compound may also be added. By containing a basic compound, generation of wrinkles due to curing shrinkage is suppressed even under low humidity where force is sufficient if ejection stability is improved. As the basic compound, all known compounds can be used. Typical examples include basic alkali metal compounds, basic alkaline earth metal compounds, basic organic compounds such as amines, and the like.

[0135] Examples of the basic alkali metal compound include alkali metal hydroxides (lithium hydroxide, sodium hydroxide, potassium hydroxide, etc.), alkali metal carbonates (lithium carbonate, charcoal). Acid sodium, potassium carbonate, etc.) and alkali metal alcoholates (sodium methoxide, sodium ethoxide, potassium methoxide, potassium ethoxide, etc.). Examples of the basic alkaline earth metal compound include alkaline earth metal hydroxides (hydroxide magnesium, hydroxide calcium, etc.) and alkali metal carbonates (magnesium carbonate, carbonate). Calcium) and alkali metal alcoholates (magnesium methoxide, etc.).

[0136] Examples of basic organic compounds include amines, nitrogen-containing bicyclic compounds such as quinoline and quinolidine, etc. Among these, amines are preferred because of their compatibility with photopolymerizable monomers. Octylamine, naphthylamine, xylenediamine, dibenzylamine, diphenylamine, dibutylamine, dioctylamine, dimethylaniline, quinuclidine, tributylamine, trioctylamine, tetramethylethylenediamine, tetramethyl-1,6-hexamethylenediamine, heme Xamethylenetetramine and triethanolamine.

[0137] The concentration of the basic compound in the presence of the compound is 10% of the total amount of the photopolymerizable monomer.

It is preferably in the range of 1000 ppm by weight, especially 20-500 ppm by weight. The basic compounds may be used alone or in combination.

[0138] In the actinic ray curable ink of the present invention, the actinic ray curable composition has a viscosity of 7-40 mPa's at 25 ° C regardless of the curing environment (temperature 'humidity). Is preferable in order to stabilize and obtain good curability.

Next, the image recording method according to the present invention will be described using the image recording apparatus 1.

[0140] When an image recording start instruction is input to the input unit 11 by the operator, the control unit 10 controls the transport device 14 to transport the recording medium P intermittently. During the intermittent conveyance, the control unit 10 controls the carriage drive source 12 and the recording heads 31, 32, 33, 34 in accordance with the timing at which the recording medium P stops, and does not cause the carriage 2 to scan. Ink is ejected from the recording heads 31, 32, 33, 34 to the recording medium P. At this time, since the control unit 10 controls the light irradiation devices 41 and 42 to emit the ultraviolet rays toward the recording medium P, the ultraviolet rays are irradiated to the ink landed on the recording medium P, and The ink is cured. By repeating this operation, an image is recorded on the recording medium P. [0141] Here, when an image is recorded on the recording medium P while the carriage 2 is reciprocating, the control unit 10 seems to have a constant sum of ink ejection amounts with respect to the reference range during the forward pass and the return pass. In addition, the recording heads 31, 32, 33, and 34 are controlled. For example, the total ink discharge amount is I, and the center A force is also between the other side ends. If the amount of ink ejected by the recording head 32 during the return pass is 12, then 1 = 11 + 12. That is, the ink is overprinted by the first set of recording heads 32 and 33 or the second set of recording heads 31 and 34 within a specific reference range. The ratio between II and 12 is not particularly limited as long as I is constant, but it is preferably 1: 1 from the viewpoint of improving image quality.

[0142] As described above, according to the image recording apparatus 1 of the present embodiment, since the total amount of ink discharged with respect to the reference range during the forward path and the backward path during the reciprocating operation of the carriage 2 is constant, Standard category The total amount of ink landed in one round trip will be uniform. Since the ultraviolet irradiation timings of the light irradiation devices 41 and 42 for the ink landed on the recording medium P during the forward pass and the return pass are the same, the ink landed during the forward pass and the ink landed during the return pass are cured at the same timing. be able to. In other words, it is possible to irradiate ultraviolet rays at the same timing both during the forward pass and during the return pass while preventing the total amount of ink in the reference range from being different for each reciprocating operation, so that unevenness in image quality can be suppressed.

[0143] Then, among the plurality of recording heads 31, 32 arranged between the one side end from the center A in the interval between the pair of light irradiation devices 41, 42, one of the recording heads 31, 32 from the Nth one from the center The distance A1, A3 from the light irradiation device 41 to the filter 43, and the light from the Nth recording head 33, 34 from the center A among the plurality of recording heads 33, 34 arranged between the center A and the other end. Since the distances A2 and A4 from the irradiation device 42 to the filter 43 are the same, the center A force is also ejected and landed by the Nth recording heads 31 and 32 between the one end and the other from the center A. The ink ejected and landed by the Nth recording heads 33 and 34 between the side ends faces the filter 43 at the same timing. This makes it possible to make the UV irradiation timing the same during the forward pass and during the return pass while the ultraviolet ray is radiated from the filter 43.

[Second Embodiment] In the first embodiment, the force exemplifies the case where the plurality of recording heads 31, 32, 33, 34 are arranged in parallel to the transport direction X. In the second embodiment, the plurality of recording heads An image recording apparatus 1A in which the head is arranged to be inclined with respect to the transport direction X will be described. Note that the same parts as those of the image recording apparatus 1 of the first embodiment are denoted by the same reference numerals and description thereof is omitted.

FIG. 3 is a bottom view showing the carriage 2 of the image recording apparatus 1A. As shown in FIG. 3, it is arranged on the carriage 2 of the image recording apparatus 1A so as to be parallel to the plurality of recording heads 35, 36, 37, 38, 39 and tilted with respect to the conveying direction X. Has been. Multiple recording heads 35, 36,

Among the recording heads 37, 38, 39, the recording heads 35, 36 are located between the center における and one side end of the pair of light irradiation devices 41, 42, the recording head 37 is in the center A, and the recording heads 38, 39 are in the center A. To the other end. That is, since the recording head 37 is arranged at the center A, it is arranged between the one end from the center A and between the other end of the center A force. Accordingly, among the recording heads 35, 36, and 37 between the one end from the center A, the first recording head 37 from the center A is the recording head 37, the second is the recording head 36, and the third is the recording head 37. On the other hand, among the recording heads 37, 38, 39 between the center A and the other end, the first recording head 37 from the center A is the recording head 37, the second is the recording head 38, and the third is the recording head 39.

[0145] Then, the head side ends of the filter 44 in the pair of light irradiation devices 41, 42 are arranged at equal intervals over the entire length of the recording heads 35, 36, 37, 38, 39. 35, 36, 37,

It is designed to transmit ultraviolet rays with the same inclination as 38 and 39. Then, the interval B1 from the first recording head 37 between the center A to the filter 44 of the one light irradiation device 41 between the first recording head 37 and the other end from the first recording head 37 between the other end to the other side. The distance B2 from the light irradiation device 42 to the filter 44 is the same. Similarly, the center A force is also from the second recording head 36 between the one end and the filter B of one light irradiation device 41 to the filter 44, and from the second recording head 38 between the center A and the other end. The distance B4 from the other light irradiation device 42 to the filter 44 is the same, and the center A force is also equal to the distance B5 from the third recording head 35 between the one side ends to the filter 44 of one light irradiation device 41, and the center. The distance B6 from the third recording head 38 between A and the other end to the filter 44 of the other light irradiation device 42 is the same.

[0146] That is, among the plurality of recording heads 35, 36, and 37 disposed between one side end from the center A, the center Spaces Bl, B3, B5 from the Nth recording head 35, 36, 37 to A to the filter 44 of one light irradiation device 41, and a plurality of recording heads 37, 37 arranged between the center A and the other end A pair of light irradiation devices such that the distance B2, B4, B6 to the filter 44 of the other light irradiation device 42 is the same as the Nth recording head 37, 38, 39 force from the center of 38, 39. 41 and 42 are arranged.

Even if the recording heads 35, 36, 37, 38, 39 are inclined with respect to the transport direction X as in this image recording apparatus 1A, the intervals B1, B2, B3, B4, B5 Since the interval B6 is the same, the UV irradiation timing for the ink that has landed on the recording medium P during the forward pass and the return pass can be made the same, and the ink that landed during the forward pass and the ink that landed during the return pass can be made at the same timing. It can be cured. That is, it is possible to irradiate ultraviolet rays at the same timing both during the forward pass and during the return pass while preventing the total amount of ink in the reference range from being different for each reciprocating operation, so that unevenness in image quality can be suppressed.

[Third embodiment]

In the first embodiment, the force exemplifies the case where the plurality of recording heads 31, 32, 33, 34 are arranged in a line along the scanning direction. In the third embodiment, the plurality of recording heads The image recording apparatus 1B arranged in a plurality of stages so that the heads are stepped will be described. The same parts as those of the image recording apparatus 1 of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

FIG. 4 is a bottom view showing the carriage 2 of the image recording apparatus 1B. As shown in FIG. 4, a plurality of recording heads 31, 32, 33, 34 are arranged in a plurality of stages on the carriage 2 of the image recording apparatus 1A so as to have a stepped shape. Hereinafter, the lowermost recording heads 31, 32, 3 3, and 34 in FIG. 2 are designated as recording heads 3 la, 32a, 33a, and 34a, and the middle recording heads 31, 32, 33, and 34 are designated as recording heads 31b, 32b, and 33b. , 34b, and the uppermost recording heads 31, 32, 33, 34 will be described as recording heads 31c, 32c, 33c, 34c.

Then, the head side end portions of the filter 45 in the pair of light irradiation devices 41 and 42 are formed in a step shape corresponding to the arrangement state of the recording heads 31, 32, 33, and 34. The recording heads 31, 32, 33, 34 ί of each stage are arranged between the central force 45 at both ends of the finer 45 of the pair of light irradiation devices 41, 42. Specifically, the bottom line The recording heads 31a, 32a, 33a, 34a are arranged from the center a between the lowermost steps of the filter 45 of the pair of light irradiation devices 41, 42 to both side ends. The middle recording heads 31b, 32b, 33b, 34b are arranged from the center b between the middle stages of the filters 45 of the pair of light irradiation devices 41, 42 to both side ends. The uppermost recording heads 31c, 32c, 33c, and 34c are arranged from the center c between the uppermost portions of the filters 45 of the pair of light irradiation devices 41 and 42 to both side ends.

[0150] Also in each stage, the distance a 1, bl, cl from the first recording head 32 to one light irradiation device 41 filter 45 between the center a, b, c and one side end, and from the center A to the other The distances a2, b2, c2 from the first recording head 33 between the side ends to the filter 45 of the other light irradiation device 42 are the same. Also, the distance a3, b3, c3 from the second recording head 31 between the center a, b, c to one light irradiation device 41 to the filter 45 and the center A force between the other end 2 The distances a4, b4, c4 from the first recording head 34 to the filter 45 of the other light irradiation device 42 are the same.

[0151] Thus, for each stage, the Nth recording head 31, 32 from the center a, b, c among the plurality of recording heads 31, 32 arranged between one end from the center a, b, c. The force is also recorded in the distance between the light irradiation device 41 to the finoleta 45 a 1, a3, bl, b3, cl, c3 and the center a, b, c force, etc. Space a2, a4, b2, b4, c2, c4 and force S from the Nth recording head 33, 34 out of the centers a, b, c of the heads 33, 34 to the finalizer 45 of the other light irradiation device 42 The pair of light irradiation devices 41 and 42 are arranged so as to be the same.

[0152] Like the image recording apparatus 1B, even if a plurality of recording heads 31, 32, 33, 34 are arranged in a plurality of steps so as to form a staircase, the intervals al, bl, cl and the intervals a2, Since b2, c2, intervals a3, b3, c3 and intervals a4, b4, c4 are the same, it is possible to make the UV irradiation timing for the ink landed on the recording medium P during the forward pass and the return pass the same, The landed ink and the ink landed on the return path can be cured at the same timing. In other words, it is possible to irradiate ultraviolet rays at the same timing both during the forward pass and during the return pass while preventing the total amount of ink in the reference range from being different for each reciprocating operation, thereby suppressing image quality unevenness.

[Fourth embodiment] In the image recording apparatuses 1, 1A, and 1B of 1 to 3 described above, the order of arrangement of the ink colors ejected by the recording head is not mentioned, but in this fourth embodiment, the order of arrangement of the ink colors will be described. . Note that the same parts as those of the image recording apparatus 1 of the first embodiment are denoted by the same reference numerals and description thereof is omitted.

FIG. 5 is a bottom view showing the carriage 2 of the image recording apparatus 1C according to the fourth embodiment. As shown in FIG. 5, in the carriage 2 of the image recording apparatus 1C, for example, a plurality of recording heads 5 that eject ink onto the recording medium P are arranged at equal intervals along the scanning direction Y. The plurality of recording heads 5 is a set of two, and ink of different colors (for example, yellow (y), magenta (m), cyan (c), black (k)) is used for each set. It starts to discharge!

[0154] The plurality of recording heads 5 are arranged from the center A to both side ends in the distance between the filters 43 of the pair of light irradiation devices 41 and 42. Below, the recording head 5 that discharges yellow ink is the recording head 51, 52 for yellow, the recording head 5 that discharges magenta ink is the recording head 53, 54 for magenta, and the recording head 5 that discharges cyan ink is for cyan. The recording heads 5 and 56 and the recording head 5 that discharges black ink will be described as yellow recording heads 57 and 58. Center A force Between yellow head, yellow recording head 51, magenta recording head 53, cyan recording head 55, and black recording head 57 are arranged in the following order. The yellow recording head 52, the magenta recording head 54, the cyan recording head 56, and the black recording head 58 are arranged in the following order. That is, the ink colors ejected by the plurality of recording heads 5 are set so that the arrangement order from the center A to one side end and the arrangement order from the center A to the other end are the same with respect to the center A. ing.

[0155] As in the image recording apparatus 1C, the ink colors ejected by the plurality of recording heads 5 are arranged in such a way that the arrangement order from the center A force to one side and the arrangement order from the center A to the other side are center A. The recording heads 5 other than the recording head arranged in the center A eject ink of the same color by the two recording heads 5 (for example, the yellow recording heads 51 and 52). It becomes. Among these yellow recording heads 51 and 52, one yellow recording head 51 force The distance dl from one light irradiation device 41 to the filter 43 and the other light recording device 52 to the other light irradiation device 42. Since the distance d2 to the filter 43 is the same, the same color ink ejected from the two yellow recording heads 51 and 52 is irradiated with the same ultraviolet light. It can be cured at the shooting timing.

It should be noted that the present invention is not limited to the above embodiment, and various improvements and design changes may be made without departing from the spirit of the present invention.

Claims

The scope of the claims

[1] a recording head for recording an image by discharging photocurable ink onto a recording medium;

A pair of light irradiating devices for irradiating the recording medium with ultraviolet rays, and irradiating the ink that has landed on the recording medium with ultraviolet rays from the irradiation unit; ,

In the reciprocating operation of the carriage, the total amount of ink discharged with respect to the reference range during the forward path and during the backward path is constant, and the ultraviolet irradiation timing of the light irradiation device for the ink landed on the recording medium during the forward path and the backward path The image recording apparatus is characterized in that the recording head, the light irradiating device and the carriage are controlled so that they are the same.

[2] In the image recording device according to claim 1,!

Among the plurality of recording heads arranged between one end of the central force, the irradiation of one light irradiation device of the pair of light irradiation devices from the Nth (N is a natural number) recording head from the center. And from the Nth recording head among the plurality of recording heads arranged between the other ends from the center, the other light irradiation device of the pair of light irradiation devices. The pair of light irradiation devices are arranged so that the distance to the irradiation unit is the same! An image recording apparatus characterized by being beaten.

[3] In the image recording apparatus according to claim 2,

For each stage, among the plurality of recording heads arranged between one end from the center, from the Nth recording head from the center, one light irradiation device of the pair of light irradiation devices And the other of the pair of light irradiation devices from the Nth recording head among the plurality of recording heads arranged between the center and the other end. The image recording apparatus, wherein the pair of light irradiation devices are arranged so that an interval between the device and the irradiation unit is the same.

[4] In the image recording apparatus according to claim 2,

The plurality of recording heads are disposed so as to be inclined with respect to the transport direction, and the pair of the pair of the recording heads disposed between one end of the central force from the Nth recording head from the center. Among the plurality of recording heads arranged between the center and the other end, from the Nth recording head from the center, the distance to the irradiation part of one of the light irradiation devices The irradiation unit of the pair of light irradiation devices is inclined with respect to the transport direction so that the distance to the irradiation unit of the other light irradiation device is the same among the pair of light irradiation devices! An image recording apparatus characterized by fluttering.

[5] The image recording apparatus according to any one of claims 2 to 4, further comprising:

The ink colors ejected by the plurality of recording heads are set so that the arrangement order from one end to the center and the arrangement order between the other ends of the central force are the same with respect to the center. An image recording device characterized by squeezing.

[6] A photocurable ink is ejected from a recording head onto a recording medium to record an image, and the ink that has landed on the recording medium is cured by irradiating a pair of light irradiation devices with ultraviolet rays. For the image recording method,

In the reciprocating operation of the carriage, the total amount of ink discharged with respect to the reference range during the forward path and during the backward path is constant, and the ultraviolet irradiation timing of the light irradiation device for the ink landed on the recording medium during the forward path and the backward path An image recording method characterized by the fact that they are the same.

[7] In the image recording method according to claim 6,

A plurality of the recording heads are disposed on the carriage at a distance between the pair of light irradiation devices. Arranged between the center and both ends

Among the plurality of recording heads arranged between one end of the central force, the irradiation unit of one of the pair of light irradiation devices from the Nth (N is a natural number) recording head from the center. And from the Nth recording head of the plurality of recording heads arranged between the center and the other end, the second light irradiation device of the pair of light irradiation devices The pair of light irradiation devices are arranged so that the distance to the irradiation unit is the same! An image recording method characterized in that the image is printed.

[8] In the image recording method according to claim 7,

The irradiation unit of one light irradiation device of the pair of light irradiation devices from the Nth recording head among the plurality of recording heads arranged between one end from the center for each stage. And the irradiation of the other light irradiation device of the pair of light irradiation devices from the Nth recording head among the plurality of recording heads arranged between the center and the other end. An image recording method, wherein the pair of light irradiating devices are arranged so that the distance to the portion is the same.

[9] In the image recording method according to claim 7,

The plurality of recording heads are disposed so as to be inclined with respect to the transport direction, and the pair of the pair of the recording heads disposed between one end of the central force from the Nth recording head from the center. Among the plurality of recording heads arranged between the center and the other end, from the Nth recording head from the center, the distance to the irradiation part of one of the light irradiation devices The irradiation unit of the pair of light irradiation devices is inclined with respect to the transport direction so that the distance to the irradiation unit of the other light irradiation device is the same among the pair of light irradiation devices! An image recording method characterized by fluttering.

[10] In the image recording method according to any one of claims 7 to 9,

The ink colors ejected by the plurality of recording heads are set so that the arrangement order from one end to the center and the arrangement order between the other ends of the central force are the same with respect to the center. ! An image recording method characterized by scolding.