JP2007069422A - Liquid applicator and application method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To apply a plurality of liquids at an optimal liquid quantity ratio when being applied. <P>SOLUTION: The liquid applicator comprises a section 12 for applying first liquid containing a polymerization initiator, second liquid containing a polymerizable compound, and third liquid containing an object being fixed to a predetermined medium through polimerization reaction of the polymerizable compound to the medium, a UV light source 126 as a means for irradiating the medium applied with the first liquid, second liquid and the third liquid with radiation, a use detecting section 132, a print mode detecting section 134 and a medium type detecting section 136 as a means for detecting the output conditions of the medium, and a print control section 150 as a means for controlling the quantity ratio of respective liquids being applied to the medium at the liquid applying section based on the detected output conditions. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid application apparatus and a liquid application method, and more particularly, to a liquid application apparatus and a liquid application method for optimizing the amount of liquid when applying a liquid to a predetermined medium.

  2. Description of the Related Art Conventionally, an ink discharge head having a plurality of nozzles (discharge ports) for discharging ink is arranged, and the ink discharge head and a recording medium such as paper are moved relative to each other while moving toward the recording medium. 2. Related Art Ink jet printers that apply ink onto a recording medium by ejecting ink are known.

  Moreover, the thing using a polymerization reaction is known. In the polymerization reaction, radiation (radiation rays) such as ultraviolet rays is irradiated to activate the polymerization initiator, and starting species such as radicals are generated from this to polymerize a polymerizable compound such as a monomer or a prepolymer. The colorant (coloring material) in the ink is fixed to the recording medium by the polymerizable compound cured by such a polymerization reaction.

Note that Patent Document 1 discloses that during recording or recording, a reaction liquid containing a reactive agent and ink are attached to a recording medium, and the aggregate is formed by bringing the reactive agent into contact with the ink to perform recording on the recording medium. Later, it is described that the recording medium is irradiated with ultraviolet rays and / or heated.
Japanese Patent No. 3642152

  There is a problem that the amount of liquid is not optimized according to output conditions such as the use of the recording medium, the type of the recording medium, and the printing mode indicating the printing mode.

  For example, the strength of the required weather resistance differs depending on whether the recording medium is used indoors or outdoors such as a poster posted outdoors. Specifically, the outdoor use is more exposed to sunlight than the indoor use, so that strong weather resistance is required so that the recorded image does not fade.

  However, the ratio between the colorant and the polymerizable compound in the UV ink applied to the recording medium is generally determined in accordance with one of the indoor and outdoor conditions, that is, it is constant and can be changed. Can not. For example, an ink in which a colorant and a polymerizable compound are mixed in a mixing ratio suitable for outdoor use (for example, one-component UV) when a user tries to use not only indoor but also outdoor recording with a single inkjet printer. When an apparatus that applies ink) to a recording medium is used, it is over-spec for indoor use, and various problems occur. For example, adverse effects such as an increase in the brittleness of the surface of an image recorded on a recording medium and the occurrence of color turbidity inevitably occur. On the other hand, when using an apparatus that applies to a recording medium an ink in which a colorant and a polymerizable compound are mixed at a mixing ratio suitable for indoor use, the aforementioned weather resistance problem, that is, fading easily occurs in outdoor use. The problem arises.

  Because of these problems, the user cannot actually use one inkjet printer for both indoor recording and outdoor recording, and when recording indoors, On the other hand, when performing outdoor recording, an apparatus suitable for outdoor recording must be used. That is, the user is forced to prepare and install a plurality of inkjet printers.

  Further, it is necessary to optimize the amount of liquid to be used, not only depending on the use of the recording medium, but also depending on the type of the recording medium and the printing mode. However, in the two-component UV ink, there is no known document describing optimizing the droplet volume ratio of a plurality of liquids according to the output conditions such as the use of the recording medium, the type of the recording medium, and the printing mode.

  The present invention has been made in view of such circumstances, and a liquid application device and a liquid application device that can apply a plurality of types of liquids to a medium at an optimal liquid amount ratio when applying a plurality of types of liquids to the medium. It aims to provide a method.

  In order to achieve the above object, the invention described in claim 1 is directed to a liquid application unit that performs recording by applying a plurality of types of liquid to a predetermined medium, a type of the medium, and a printing that indicates a printing mode of the medium. An application ratio control means for changing a ratio of the amount of liquid between a plurality of types of liquid applied to the medium according to a mode, use of the medium, a combination thereof, or other output conditions of the medium. A liquid applicator characterized by the above is provided.

  According to this invention, when a plurality of types of liquid are applied to the medium, the plurality of types of liquid are applied to the medium at an optimal liquid amount ratio based on the output conditions of the medium.

  According to a second aspect of the present invention, there is provided a first liquid containing a polymerization initiator, a second liquid containing a polymerizable compound, and a third liquid containing an object to be fixed to a predetermined medium by a polymerization reaction of the polymerizable compound. A liquid applying means for applying the liquid to the medium, a radiation irradiating means for irradiating the medium to which the first liquid, the second liquid and the third liquid are applied, and an output for detecting an output condition of the medium Based on the detection result by the condition detection means and the output condition detection means, the liquid application means provides the medium with the first liquid, the second liquid, and the third liquid. A liquid application apparatus characterized by comprising application ratio control means for controlling the ratio of the amount of liquid between at least two kinds of liquids.

  According to this invention, based on the output condition of the medium, the first liquid containing the polymerization initiator, the second liquid containing the polymerizable compound, and the fixing target to be fixed to the predetermined medium by the polymerization reaction of the polymerizable compound. Since the ratio of the liquid amount between at least two liquids among the three liquids of the third liquid including the liquid is controlled, a plurality of types of liquids are applied to the medium at the optimal liquid amount ratio, The weather resistance, brittleness, and reaction efficiency can be improved.

  As a mode of controlling the ratio of the liquid amount by the application ratio control means, specifically, first, the liquid amount of the third liquid including the fixing target to be fixed to the medium by the polymerization reaction of the polymerizable compound and the polymerization There is an aspect in which the ratio of the liquid amount of the first liquid containing the polymerization initiator that initiates the polymerization reaction of the adhesive compound is controlled, and secondly, the liquid amount of the third liquid including the fixing object and the polymerizable compound are included. There is an aspect of controlling the ratio of the liquid amount of the second liquid, and thirdly, the ratio of the liquid amount of the first liquid containing the polymerization initiator and the liquid amount of the second liquid containing the polymerizable compound is controlled. There is a mode, and fourthly, there is a mode of controlling the ratio of the liquid amount among all of the first liquid, the second liquid, and the third liquid.

  The invention according to claim 3 is the invention according to claim 2, wherein the third liquid contains the polymerizable compound, and is fixed to the medium by a polymerization reaction of the polymerizable compound and the polymerizable compound. The second liquid containing the polymerizable compound is further applied to the medium by the liquid application unit after the third liquid including the fixing target is applied to the medium by the liquid application unit. A liquid applicator is provided.

  According to the present invention, overcoat is possible, and weather resistance can be improved and smoothed.

  According to a fourth aspect of the present invention, there is provided a liquid applying means for applying a first liquid containing a polymerization initiator and a second liquid containing a polymerizable compound to a predetermined medium, the first liquid and the second liquid. Radiation irradiation means for irradiating the applied medium, output condition detection means for detecting the output condition of the medium, and application to the medium by the liquid application means based on the detection result by the output condition detection means There is provided a liquid application apparatus comprising an application ratio control means for controlling a ratio between the liquid amount of the first liquid and the liquid amount of the second liquid.

  According to this invention, since the ratio of the liquid amount of the first liquid containing the polymerization initiator and the liquid amount of the second liquid containing the polymerizable compound is controlled based on the output condition of the medium, the optimum liquid amount ratio Thus, the first liquid and the second liquid can be applied to the medium, and the weather resistance, the brittleness, and the reaction efficiency can be improved.

  According to a fifth aspect of the present invention, in the fourth aspect of the present invention, any one of the first liquid and the second liquid is an object to be fixed to the medium by a polymerization reaction of the polymerizable compound. A liquid application device is provided.

  A sixth aspect of the present invention provides the liquid application apparatus according to any one of the second to fifth aspects, wherein the fixing object is a colorant.

  The invention according to claim 7 is the invention according to any one of claims 2 to 6, wherein the output condition includes a type of the medium, a printing mode indicating a printing mode of the medium, and a state of the medium. A liquid applicator is provided that includes at least one of its uses.

  According to the eighth aspect of the present invention, when recording is performed by applying a plurality of types of liquids to a predetermined medium, the type of the medium, the printing mode indicating the printing mode of the medium, the use of the medium, or these The liquid application method is characterized in that the ratio of the amount of liquid between a plurality of types of liquid applied to the medium is changed according to the combination of the above and other output conditions of the medium.

  Examples of the radiation include ultraviolet rays and electron beams.

  According to the present invention, when a plurality of types of liquid are applied to the medium, the plurality of types of liquid can be applied to the medium at an optimal liquid amount ratio.

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

  FIG. 1 is a block diagram showing an example of the overall configuration of an image forming apparatus 10 according to an embodiment of the present invention.

  1, the image forming apparatus 10 mainly includes a liquid application unit 12 (liquid application unit), a communication interface 110, a system controller 112, memories 114 and 152, a conveyance unit 116, a conveyance driver 118, and a UV light source 126 (radiation irradiation unit). ), Light source driver 128, liquid supply unit 142, liquid supply control unit 144, application detection unit 132, print mode detection unit 134, medium type detection unit 136, print control unit 150 (application ratio control means), and head driver 154. It is comprised including.

  In the present embodiment, the liquid application unit 12 is configured by arranging a plurality of liquid ejection heads 50 of FIG. 2 to be described later, and applies liquid to a predetermined recording medium such as paper.

  The communication interface 110 is an image data input unit that receives image data sent from the host computer 300. As the communication interface 110, a wired or wireless interface such as USB (Universal Serial Bus) or IEEE1394 can be applied.

  Image data transmitted from the host computer 300 is taken into the image forming apparatus 10 via the communication interface 110 and temporarily stored in the first memory 114.

  The system controller 112 includes a central processing unit (CPU) and its peripheral circuits, and is a main control unit that controls the entire image forming apparatus 10 according to a predetermined program. That is, the system controller 112 controls each unit such as the communication interface 110, the conveyance driver 118, the light source driver 128, and the print control unit 150.

  The conveyance unit 116 includes a conveyance motor, a belt, a roller, and the like that are not illustrated. The conveyance motor applies power to the conveyance rollers and belts. The conveying belt sucks and conveys the recording medium.

  The transport driver 118 is a circuit that drives the motor of the transport unit 116 in accordance with an instruction from the system controller 112.

  The UV (ultraviolet) light source 126 is a light source that irradiates the recording medium conveyed by the conveyance unit 116 with ultraviolet rays.

  The light source driver 128 is a circuit that drives the UV light source 126 in accordance with an instruction from the system controller 112.

  The usage detection unit 132 detects the usage of the recording medium.

  There are various detection modes for applications. For example, it is automatically detected by analyzing an aspect input by a user operation, an aspect input from the host computer 300, and image data (for example, resolution or color) input from the host computer 300. There is a mode to do so.

  The print mode detection unit 134 detects a print mode indicating a printing mode (recording mode) of the recording medium.

  There are various types of print mode detection modes. For example, it is automatically detected by analyzing an aspect input by a user operation, an aspect input from the host computer 300, and image data (for example, resolution or color) input from the host computer 300. There is a mode to do so.

  The medium type detection unit 136 detects the type of the recording medium.

  There are various detection modes for the type of recording medium. For example, a mode in which a sensor is provided in a recording medium supply unit (not shown) and detection is performed, a mode in which the sensor is input by a user operation, a mode in which the data is input from the host computer 300, and a mode in which the data is input from the host computer 300 There is a mode in which automatic detection is performed by analyzing the image data (for example, resolution and color).

  The liquid supply unit 142 includes an ink tank serving as an ink storage unit that stores ink, a pipe that allows ink to flow from the ink tank to the liquid application unit 12, a pump, and the like.

  The liquid supply control unit 144 performs control to supply ink to the liquid applying unit 12 using the liquid supply unit 142 in accordance with an instruction from the system controller 112.

  Based on the image data input to the image forming apparatus 10, the print control unit 150 causes each of the liquid discharge heads 50 constituting the liquid applying unit 12 to eject droplets onto the recording medium, thereby forming dots on the recording medium. It functions as an image processing means for generating dot data necessary for formation. That is, the print control unit 150 performs image processing such as various processes and corrections for generating dot ejection dot data from the image data in the first memory 114 according to the control of the system controller 112, and generates the generated dots. Data is supplied to the head driver 154.

  The print control unit 150 variably controls the amount of liquid applied to the recording medium by the liquid applying unit 12. Specifically, the ratio of the amount of liquid ejected from the plurality of liquid ejection heads 50 constituting the liquid application unit 12 toward the recording medium is changed. Here, changing the ratio of the liquid amount is performed by changing, for example, the number of droplets to be ejected, the amount of droplets, and the ejection frequency for each liquid ejection head 50.

  The print controller 150 is accompanied by a second memory 152 as an image buffer memory, and image data, parameters, and other data are temporarily stored in the second memory 152 during image processing in the print controller 150. In addition, the second memory 152 stores a discharge ratio change table (also referred to as a determination table) for changing the ratio of the liquid amount for each liquid discharge head 50 as will be described later.

  In FIG. 1, the second memory 152 is shown as being attached to the print control unit 150, but can also be used as the first memory 114. Also possible is an aspect in which the print controller 150 and the system controller 112 are integrated and configured with one processor.

  The head driver 154 drives the liquid ejection head 50 constituting the liquid applying unit 12 based on the dot data given from the print control unit 150 (specifically, the dot data stored in the second memory 152). A drive signal is output.

  When the drive signal output from the head driver 154 is applied to the liquid ejection head 50 of the liquid application unit 12, the liquid is ejected from the liquid ejection head 50 to the recording medium, thereby applying the liquid to the recording medium. The

[Liquid application part]
FIG. 2 is a perspective plan view schematically showing an example of the overall structure of the liquid ejection head 50 constituting the liquid applying unit 12 of FIG.

  In FIG. 2, the liquid discharge head 50 is supplied with ink into a nozzle 51 (discharge port) that discharges ink toward a recording medium such as paper, a pressure chamber 52 that communicates with the nozzle 51, and the pressure chamber 52. A plurality of pressure chamber units 54 including ink supply ports 53 as openings are arranged in a two-dimensional array. In FIG. 2, for convenience of illustration, some pressure chamber units 54 are omitted.

  The plurality of nozzles 51 are arranged along two directions: a main scanning direction (in this embodiment, a direction substantially orthogonal to the recording medium conveyance direction) and an oblique direction that forms a predetermined angle θ with respect to the main scanning direction. They are arranged in a two-dimensional matrix. Specifically, a plurality of nozzles 51 are arranged at a constant pitch d along an oblique direction that forms an angle θ with respect to the main scanning direction, whereby each nozzle 51 is predetermined on a straight line along the main scanning direction. Can be handled equivalently to those arranged at a pitch “d × cos θ”. According to such a nozzle arrangement, for example, a configuration substantially equivalent to a high-density nozzle arrangement of 2400 nozzles per inch (2400 nozzles / inch) along the main scanning direction can be achieved. That is, the density of the substantial nozzle interval (projection nozzle pitch) projected so as to be arranged on a line along the longitudinal direction (main scanning direction) of the liquid ejection head 50 is achieved. As shown in FIG. 2, the nozzle arrangement along the two directions is referred to as a two-dimensional matrix nozzle arrangement.

  The plurality of pressure chambers 52 communicating with the plurality of nozzles 51 on a one-to-one basis are also arranged in a two-dimensional matrix like the nozzles 51.

  In implementing the present invention, the arrangement structure of the nozzles 51 and the like is not particularly limited to the example shown in FIG. For example, a short liquid discharge head block in which a plurality of nozzles 51 are two-dimensionally arranged is connected in a staggered manner to connect a liquid discharge head having a nozzle row having a length corresponding to the entire width of the recording medium. It may be configured.

  FIG. 3 is a cross-sectional view showing an example of the internal structure of the liquid ejection head 50.

  In FIG. 3, an ink discharge head 50 mainly generates nozzles 51 that discharge ink, a pressure chamber 52 that communicates with the nozzles 51, and pressure generation that applies pressure to the liquid in the pressure chamber 52 by changing the volume of the pressure chamber 52. An actuator 580 as means and a common liquid chamber 55 communicating with the pressure chamber 52 are included.

  The nozzle 51, the pressure chamber 52, and the ink supply port 53 of the pressure chamber 52 are the same as those shown in FIG.

  Further, a plurality of nozzles 51, pressure chambers 52, and actuators 580 are actually provided.

  The vibration plate 56 constitutes one wall surface (vibration surface) of the pressure chamber 52, and a piezoelectric body 58 is fixed to the vibration plate 56 on the side opposite to the side where the pressure chamber 52 is formed. The individual electrodes 57 are formed so as to sandwich the diaphragm 56 with the diaphragm 56. The piezoelectric body 58 is made of, for example, piezo, and when a predetermined electric signal (driving signal) is given to the individual electrode 57, displacement (distortion) is generated, and the volume of the pressure chamber 52 is changed via the diaphragm 56. The diaphragm 56, the piezoelectric body 58, and the individual electrode 57 constitute an actuator 580 as a pressure generating means.

  The diaphragm 56 in this embodiment is common to the plurality of pressure chambers 52 and is formed of a single plate, but is not particularly limited to such a case, and is formed for each pressure chamber 52. There may be.

  The common liquid chamber 55 supplies ink supplied from an upstream ink tank (not shown) to the pressure chamber 52 via the ink supply port 53.

  The individual electrodes 57 of the actuator 580 are connected to the head driver 154 in FIG. 1 via electric wiring (drive wiring) (not shown). The amount of liquid ejected from the nozzles 51 of the liquid ejection head 50 by changing the waveform (driving waveform) of an electric signal (driving signal) given from the head driver 154 to the actuator 580 (specifically, the individual electrode 57). The (liquid proper amount) can be changed. Such drive waveform control is performed by the print controller 150 in FIG. 1 instructing the drive waveform to the head driver 154.

  In the present invention, as means for applying the liquid onto the recording medium, other liquid applying means such as coating may be used in addition to the means for discharging the liquid from the nozzle.

  There is no restriction | limiting in particular as an apparatus used for the said application | coating, A well-known coating apparatus can be suitably selected according to the objective. Examples include air doctor coaters, blade coaters, lot coaters, knife coaters, squeeze coaters, impregnation coaters, reverse roll coaters, transfer roll coaters, gravure coaters, kiss roll coaters, cast coaters, spray coaters, curtain coaters, extrusion coaters, etc. It is done.

[Substances contained in liquid]
The substance in the liquid provided to the recording medium by the liquid applying apparatus according to the present invention will be described in detail.

  In the image forming apparatus shown in the present embodiment, a polymerizable compound (radiation curable “monomer” and “prepolymer”), a polymerization initiator (also referred to as “curing initiator”), and a colorant (“coloring material”). And a liquid containing one or a plurality of substances selected from a diffusion inhibitor and a high-boiling solvent (specifically oil).

<Polymerizable compound (radiation curable monomer and prepolymer)>
The polymerizable compound refers to a compound having a function of causing a polymerization reaction and curing by an initiating species such as a radical generated from a polymerization initiator described later.

  It is preferably an addition polymerizable compound having at least one ethylenically unsaturated double bond, and is preferably selected from polyfunctional compounds having at least one terminal ethylenically unsaturated bond, more preferably two or more. Such compound groups are widely known in the industrial field, and these can be used without any particular limitation. These include, for example, those having chemical forms such as monomers, prepolymers, that is, dimers, trimers and oligomers, or mixtures thereof and copolymers thereof.

  The polymerizable compound preferably has a polymerizable group such as an acryloyl group, a methacryloyl group, an allyl group, a vinyl group, or an internal double bond group (such as maleic acid) in the molecule, and among them, an acryloyl group or a methacryloyl group. A compound having a group is preferable because it can cause a curing reaction with low energy.

  Only one type of polymerizable compound may be used in one liquid, or two or more types may be used in combination.

  As content rate of the polymeric compound contained in the liquid containing a coloring agent, the range of 50-99 mass% is preferable in a liquid, The range of 70-99 mass% is more preferable, The range of 80-99 mass% is further preferable.

<Polymerization initiator (curing initiator)>
The polymerization initiator refers to a compound that generates an initiation species such as a radical by the energy of light, heat, or both, and initiates and accelerates the polymerization of the polymerizable compound, and is a known thermal polymerization initiator or bond dissociation energy. A compound having a small bond, a photopolymerization initiator and the like can be selected and used.

  Examples of such radical generator include organic halogenated compounds, carbonyl compounds, organic peroxide compounds, azo polymerization initiators, azide compounds, metallocene compounds, hexaarylbiimidazole compounds, organic boric acid compounds, disulfonic acid compounds, oniums. Examples thereof include salt compounds.

  In the present invention, at least one of the plural types of liquids used contains a polymerization initiator that cures the polymerizable compound.

  The content of the polymerization initiator is preferably 0.5 to 20% by mass, and 1 to 15% by mass with respect to the total polymerizable compound used in the ink set from the viewpoints of stability over time, curability, and curing rate. More preferred is 3 to 10% by mass.

  A polymerization initiator can be used 1 type or in combination of 2 or more types. Further, as long as the effects of the present invention are not impaired, a known sensitizer can be used in combination for the purpose of improving sensitivity.

<Colorant (coloring material)>
Examples of the colorant include pigments and dyes.

  The colorant used in the present invention is not particularly limited, and can be appropriately selected from known water-soluble dyes, oil-soluble dyes and pigments as long as they can achieve a hue and color density suitable for the intended use of the ink. be able to. Among them, the liquid constituting the ink for ink jet recording is preferably a water-insoluble liquid that does not contain an aqueous solvent from the viewpoint of ink droplet stability and quick-drying. It is preferable to use an oil-soluble dye or pigment that is easily dispersed and dissolved in a water-soluble liquid.

  There is no restriction | limiting in particular in the oil-soluble dye which can be used for this invention, Arbitrary things can be used. The content of the dye when using an oil-soluble dye as the colorant is preferably in the range of 0.05 to 20% by mass, more preferably 0.1 to 15% by mass, and more preferably 0.2 to 0.2% in terms of solid content. 6% by mass is particularly preferred.

  An embodiment in which a pigment is used as the colorant is also preferable from the viewpoint that aggregation easily occurs when a plurality of liquids are mixed.

  As the pigment used in the present invention, either an organic pigment or an inorganic pigment can be used, and as the black pigment, a carbon black pigment or the like is preferably exemplified. In general, pigments of three primary colors of black and cyan, magenta, and yellow are used, but pigments having other hues such as red, green, blue, brown, white, gold, silver, etc. The metallic luster pigment, colorless or light-colored extender pigment, and the like can also be used depending on the purpose.

  In addition, particles having silica, alumina, resin, or the like as a core material and having a dye or pigment fixed on the surface, an insoluble raked product of a dye, a colored emulsion, a colored latex, or the like can also be used as a pigment.

  Furthermore, resin-coated pigments can also be used. This is called a microcapsule pigment, and is also available as a commercial product from Dainippon Ink and Chemicals, Toyo Ink, etc.

  The volume average particle diameter of the pigment particles contained in the liquid in the present invention is preferably in the range of 30 to 250 nm, more preferably 50 to 200 nm, from the viewpoint of balance between optical density and storage stability. . Here, the volume average particle diameter of the pigment particles can be measured by a measuring device such as LB-500 (manufactured by HORIBA).

  In the case of using a pigment as a colorant, the content is preferably in the range of 0.1% by mass to 20% by mass in terms of solid content in the liquid from the viewpoint of optical density and jetting stability, and preferably 1% by mass. More preferably, it is in the range of -10% by mass.

  The colorant may be used alone or in combination of two or more. Further, different colorants may be used for each liquid, or the same may be used.

<Diffusion inhibitor>
In the present invention, the diffusion preventing agent refers to a substance that prevents the diffusion and bleeding of the liquid having the colorant applied to the recording medium.

  The diffusion inhibitor contains at least one selected from the group consisting of a polymer having an amino group, a polymer having an onium group, a polymer having a nitrogen-containing heterocycle, and a metal compound.

  The said polymer etc. may use single type and may use it in combination of multiple types. “Multiple species” refers to, for example, different genus species that belong to polymers having an amino group but have different structures, or a relationship between a polymer having an amino group and a polymer having an onium group. Including some cases. Further, an amino group, an onium group, a nitrogen-containing heterocycle, and a metal compound may be combined in one molecule.

<High boiling point organic solvent (oil)>
The high boiling point organic solvent in the present invention means an organic solvent having a viscosity at 25 ° C. of 100 mPa · s or less or a viscosity at 60 ° C. of 30 mPa · s or less and a boiling point higher than 100 ° C.

  Here, the “viscosity” in the present invention refers to a viscosity obtained using a RE80 viscometer manufactured by Toki Sangyo Co., Ltd. The RE80 type viscometer is a conical rotor / plate type viscometer corresponding to the E type. Measurement is performed at a rotation speed of 10 rpm using the first rotor. However, for those having a viscosity higher than 60 mPa · s, measurement is performed by changing the number of revolutions to 5 rpm, 2.5 rpm, 1 rpm, 0.5 rpm, or the like as necessary.

  In the present invention, “water solubility” is the saturation concentration of water in a high-boiling organic solvent at 25 ° C., and means the mass (g) of water that can be dissolved in 100 g of the high-boiling organic solvent at 25 ° C. .

  As the usage-amount of the said high boiling point organic solvent, 5-2000 mass% is preferable in conversion of coating amount with respect to the coloring agent to be used, and 10-1000 mass% is more preferable.

<Storage stabilizer>
In the present invention, a storage stabilizer can be added for the purpose of suppressing undesired polymerization during storage of plural kinds of liquids. The storage stabilizer is preferably used in the same liquid as the polymerizable compound, and it is preferable to use a storage stabilizer that is soluble in the liquid or other coexisting components.

  Examples of the storage stabilizer include quaternary ammonium salts, hydroxyamines, cyclic amides, nitriles, substituted ureas, heterocyclic compounds, organic acids, hydroquinones, hydroquinone monoethers, organic phosphines, copper compounds, and the like. .

  The addition amount of the storage stabilizer is preferably adjusted as appropriate based on the activity of the polymerization initiator used, the polymerizability of the polymerizable compound, and the type of the storage stabilizer. However, the storage stability and the curability of the ink during liquid mixing are preferred. From the standpoint of balance, the amount is preferably 0.005 to 1% by mass in terms of solid content in the liquid, more preferably 0.01 to 0.5% by mass, and still more preferably 0.01 to 0.2% by mass. .

[Energy application process]
In the present invention, ultraviolet light, visible light, or the like can be used as an exposure light source for proceeding polymerization of the polymerizable compound. In addition, energy can be applied by radiation other than light, for example, α-ray, γ-ray, X-ray, electron beam, etc. Of these, ultraviolet rays and visible rays are used from the viewpoint of cost and safety. Preferably, ultraviolet rays are used. The amount of energy required for the polymerization reaction varies depending on the type and content of the polymerization initiator, but is generally about 1 to 500 mJ / cm ² .

[Combination of liquid discharge head and liquid]
FIG. 4 is a configuration diagram showing the basic liquid application unit 12a and its periphery.

  The liquid application unit 12a illustrated in FIG. 4 includes a first liquid discharge head 50-1, a second liquid discharge head 50-2, and a third liquid in order from the upstream side along the conveyance direction of the recording medium 20. The discharge head 50-3 is arranged.

  The recording medium 20 includes a first liquid discharge head 50-1, a second liquid discharge head 50-2, and a third liquid discharge head 50-3 in this order. , 50-3, facing the nozzle surface (50A in FIG. 3) while being transported on the transport belt 33, a necessary amount of liquid is ejected by an appropriate amount of liquid, and then directed from the UV light source 126 to the recording medium 20. UV light is irradiated.

  FIG. 5 shows the liquid that adheres to the recording medium 20 by the ejection of the first liquid ejection head 50-1 as "first liquid", and the liquid that adheres to the recording medium 20 by the ejection of the second liquid ejection head 50-2. The “second liquid” and the liquid that adheres to the recording medium 20 by the ejection of the third liquid ejection head 50-3 are referred to as the “third liquid”, and these liquids (the first liquid, the second liquid, and the third liquid) A combination example is shown.

  In FIG. 5, the “diffusion inhibitor” is included in parentheses because it may or may not be included in the first liquid. As described above, the “polymerizable compound” includes a radiation curable monomer and a radiation curable prepolymer. The “polymerization initiator” is also referred to as “curing initiator” as described above. As described above, the “colorant” is also referred to as “coloring material”. Further, the above-mentioned oil as “high boiling point organic solvent” and “storage stabilizer” are contained in an appropriate amount in the liquid.

  In the first combination example, the first liquid mainly includes a polymerization initiator and a diffusion inhibitor, the second liquid mainly includes a colorant and a polymerizable compound, and the third liquid mainly includes a polymerizable compound.

  According to such a first combination example, since the diffusion preventing agent is applied to the recording medium 20 prior to the colorant, landing interference is prevented. In addition, since the polymerizable compound is further applied to the recording medium 20 after the coloring agent is applied to the recording medium 20, overcoating is possible. It is also effective for weather resistance. In addition, an effect of smoothing (preventing swelling only at the ink) can be expected.

  In the second combination example, the first liquid mainly includes a polymerization initiator and a diffusion inhibitor, the second liquid mainly includes a polymerizable compound, and the third liquid mainly includes a colorant and a polymerizable compound.

  In the third combination example, the first liquid mainly contains a polymerizable compound and a diffusion inhibitor, the second liquid mainly contains a polymerization initiator, and the third liquid mainly contains a colorant and a polymerizable compound.

  According to such a third combination example, it is possible to impart the effect of modifying the recording medium 20 by first applying the polymerizable compound to the recording medium 20.

  In the first to third combination examples described above, at least three liquid discharge heads are used. According to the fourth and fifth combination examples described below, a minimum of two liquid discharge heads are used. The invention can also be implemented.

  In the fourth combination example, the first liquid mainly contains a polymerization initiator and a diffusion inhibitor, and the second liquid mainly contains a colorant and a polymerizable compound.

  In the fifth combination example, the first liquid mainly contains a polymerization initiator, a colorant and a diffusion inhibitor, and the second liquid mainly contains a polymerizable compound.

  In the fifth combination example, the diffusion preventing agent is applied to the recording medium at the same time as the colorant. However, when recording is performed at a high speed (draft mode), the first to fourth are used in order to prevent landing interference. As described in the above combination examples, it is preferable to apply the liquid containing the colorant to the recording medium 20 after applying the liquid containing the diffusion inhibitor to the recording medium 20.

  The print control unit 150 in FIG. 1 corresponds to each combination example in FIG.

  For example, in the first combination example, the liquid amount (droplet amount) of the first liquid containing the polymerization initiator applied to the recording medium 20 by the first liquid discharge head 50-1 and the second liquid discharge head 50. -2 controls the ratio of the liquid amount (droplet amount) of the second liquid containing the colorant to be applied to the recording medium 20.

  Further, for example, in the first combination example, the liquid amount (droplet amount) of the second liquid containing the colorant applied to the recording medium 20 by the second liquid discharge head 50-2 and the third liquid discharge head 50-3 controls the ratio of the third liquid containing the polymerizable compound applied to the recording medium 20 to the liquid amount (droplet amount).

  Further, for example, in the first combination example, the liquid amount (droplet amount) of the first liquid containing the polymerization initiator applied to the recording medium 20 by the first liquid discharge head 50-1, the second liquid discharge head The liquid amount (droplet amount) of the second liquid containing the colorant to be applied to the recording medium 20 by 50-2 and the polymerizable compound to be applied to the recording medium 20 by the third liquid discharge head 50-3. The ratio of all the liquid amounts (droplet amounts) of the three liquid amounts (droplet amounts) is controlled.

  Further, for example, in the first combination example, the liquid amount (droplet amount) of the first liquid containing the polymerization initiator applied to the recording medium 20 by the first liquid discharge head 50-1 and the third liquid discharge The ratio of the third liquid containing the polymerizable compound applied to the recording medium 20 by the head 50-3 with the liquid amount (droplet amount) is controlled. For example, the ratio of the liquid amount may be controlled only for the first liquid and the third liquid in an area on the recording medium to which the second liquid containing the colorant is not applied, that is, where there is no color.

  For example, in the fourth combination example, the liquid amount (droplet amount) of the first liquid containing the polymerization initiator applied to the recording medium 20 by the first liquid discharge head 50-1 and the second liquid discharge head 50. -2 controls the ratio of the liquid amount (droplet amount) of the second liquid containing the colorant and polymerizable compound applied to the recording medium 20.

  For example, in the fifth combination example, the liquid amount (droplet amount) of the first liquid containing the colorant and the polymerization initiator applied to the recording medium 20 by the first liquid discharge head 50-1 and the second liquid The ratio of the second liquid containing the polymerizable compound applied to the recording medium 20 by the discharge head 50-2 and the liquid amount (droplet amount) is controlled.

  In FIG. 4, the liquid application unit 12 a configured by the three liquid ejection heads 50-1, 50-2, and 50-3 is shown to describe a representative example of the liquid combination. The examples are not particularly limited.

  In the example shown in FIG. 6, the first liquid (including the polymerization initiator) in the first combination example in FIG. 5 is ejected toward the recording medium 20 in order from the upstream side along the conveyance direction of the recording medium 20. Liquid ejection head 50-1, liquid ejection head 50-2Y that ejects Y (yellow) ink toward the recording medium 20, and liquid ejection head 50-2M that ejects M (magenta) ink toward the recording medium 20 , A liquid ejection head 50-2C that ejects C (cyan) ink toward the recording medium 20, a liquid ejection head 50-2K that ejects K (black) ink toward the recording medium 20, and FIG. A liquid ejecting head 50-3 for ejecting the third liquid (including the polymerizable compound) of the first combination example toward the recording medium 20 is disposed, and the liquid applying unit 12b is configured. In other words, in the first combination example of FIG. 5, the ink that is the second liquid containing the colorant and the polymerizable compound is converted into Y, by the liquid discharge heads 50-2Y, M, C, and K for three inks. It is configured to eject droplets for each color of M, C, and K.

[Contents of grant ratio control process]
FIG. 7 is an explanatory diagram used for explaining the application ratio control process for controlling the liquid to be applied to the recording medium 20 at an appropriate application ratio according to the output conditions. Such an application ratio control process is mainly performed by the print control unit 150 of FIG.

  In FIG. 7, as typical examples of the output conditions, the usage of the recording medium, the printing mode indicating the printing mode on the recording medium, and the type of the recording medium are shown as examples.

  Further, as the classification of the usage of the recording medium, an example is shown for outdoor posting and viewing outdoors such as a poster, indoor photo browsing indoors as a photograph, and indoor document browsing indoors as a document.

  Further, as a classification of the print mode, a high-definition mode for performing high-definition recording and a draft mode for performing recording at a higher speed than the high-definition mode are illustrated.

  In addition, as a classification of the recording medium type, a non-penetrable medium in which the liquid hardly penetrates into the recording medium, a weakly permeable medium (for example, art paper, coated paper, etc.) having a permeation degree equal to or lower than a predetermined threshold value for the liquid On the other hand, a permeation medium having a permeation degree higher than a predetermined threshold is exemplified.

  The contents of the grant ratio control process corresponding to the various output conditions shown in FIG. 7 will be described.

  The liquid application ratio is expressed as an increase / decrease ratio (application coefficient) with respect to the liquid amount under specific standard conditions.

  In the example shown in FIG. 7, the case where the usage of the recording medium is “indoor photo”, the printing mode is “high definition”, and the recording medium type is “weakly penetrating medium” is “standard condition”. It is.

  Under such standard conditions, the ratio of the amount of polymerization initiator to the amount of ink, the ratio of the amount of polymerizable compound to the amount of ink, and the ratio of the amount of diffusion inhibitor to the amount of ink are determined in advance as reference ratios, respectively. Yes.

  In the case of the first combination example of FIG. 5, specifically, the application of the first liquid containing the polymerization initiator to the recording medium with respect to the application amount of the second liquid containing the colorant to the recording medium. The ratio of the amount and the ratio of the application amount of the third liquid containing the polymerizable compound to the recording medium are adjusted. Here, the polymerizable compound is contained not only in the third liquid but also in the second liquid. However, the amount of the polymerizable compound contained in the second liquid is kept constant, and the amount of the third liquid applied depends on the output conditions. To adjust.

  Specifically, the liquid application ratio to the recording medium is controlled as shown in the control content column of FIG.

  First, when the recording medium is used outdoors, the amount of the polymerizable compound is increased as compared with the case where the recording medium is used under standard conditions. For example, “1.2” times. Actually, the third liquid (polymerizable compound) with respect to the liquid amount of the second liquid (including the colorant) so that the amount of the polymerizable compound is 1.2 times the amount of the polymerizable compound under the standard conditions. (Including the liquid amount ratio) is variably set. When variably set in this way, the weather resistance of the colorant on the recording medium is improved.

  Secondly, when the recording medium is used for indoor documents, the amount of the polymerizable compound is reduced as compared with the case of the standard condition. For example, “0.8” times. Actually, the third liquid (polymerizable compound) with respect to the liquid amount of the second liquid (including the colorant) so that the amount of the polymerizable compound is 0.8 times the amount of the polymerizable compound under the standard conditions. (Including the liquid amount ratio) is variably set. Such variable setting improves brittleness.

  Third, when the printing mode is the draft (high speed) mode, the amount of the polymerization initiator is increased as compared with the case of the standard condition. For example, “1.2” times. Actually, the first liquid (polymerization initiator) with respect to the liquid amount of the second liquid (including the colorant) so that the amount of the polymerization initiator is 1.2 times the amount of the polymerization initiator under the standard conditions. (Including the liquid amount ratio) is variably set. Such variable setting increases the reaction efficiency.

  Fourth, when the type of the recording medium is a non-penetrable medium, the amount of the polymerization initiator is reduced as compared with the standard condition. For example, “0.9” times. Actually, the first liquid (polymerization initiator) with respect to the liquid amount of the second liquid (including the colorant) so that the amount of the polymerization initiator is 0.9 times the amount of the polymerization initiator under the standard conditions. (Including the liquid amount ratio) is variably set. When variably set as described above, the liquid is not absorbed into the non-penetrable medium, so that the necessary and sufficient amount of the polymerization initiator is efficiently used.

  Fifth, when the type of the recording medium is a permeation medium, the amount of the polymerization initiator is increased as compared with the standard condition. For example, “1.5” times. Actually, the first liquid (polymerization initiator) with respect to the liquid amount of the second liquid (including the colorant) so that the amount of the polymerization initiator is 1.5 times the amount of the polymerization initiator under the standard conditions. (Including the liquid amount ratio) is variably set. When variably set in this way, absorption of the liquid into the permeation medium is compensated for and sufficient curing is performed.

  FIG. 8 shows a basic configuration example of the table information 80 (ejection ratio change table) used in the application ratio control process by the print controller 150.

  In FIG. 8, the table information 80 includes the ratio of the liquid amount of the first liquid, the liquid amount of the second liquid, and the liquid amount of the third liquid for each output condition (C1, C2, C3,...). Are listed.

  The table information 800 (discharge ratio change table) as a specific example shown in FIG. 9 includes a combination of three output conditions of the usage of the recording medium, the printing mode and the recording medium type, and the amounts of the polymerization initiator and the polymerizable compound. It shows the correspondence.

  In the table information 800, the amounts of the polymerization initiator and the polymerizable compound are indicated based on a predetermined amount (standard amount) under specific standard conditions (C11).

  The standard condition (C11) is that the usage of the recording medium is “indoor photo”, the printing mode is “high definition”, and the recording medium type is “weak penetration”.

  Specifically, “1” (1 time) indicating the standard amount is registered as the amount of the polymerization initiator and the polymerizable compound under the standard condition (C11).

  In addition, as the amounts of the polymerization initiator and the polymerizable compound in the output conditions (C1 to C10, C12 to C18) other than the standard conditions, specifically, a magnification with respect to the standard amount is registered. The absolute amount of the polymerization initiator and the polymerizable compound is obtained by multiplying the magnification by the standard amount.

  Here, the correspondence between the amounts of the polymerization initiator and the polymerizable compound shown in FIG. 9 and the contents of the application control process shown in FIG. 7 will be described.

  First, as already described with reference to FIG. 7, when the use is “outdoor use”, the amount of the polymerizable compound is increased as compared with the case of the standard condition (C11). For example, the amount of the polymerizable compound is 1.2 times the standard amount (C1 to C6). Also, the polymerization initiator is increased or decreased according to the print mode and the recording medium type as already described with reference to FIG. For example, if the amount of the polymerization initiator is “draft” and “penetration”, it is 1.8 (= 1.2 × 1.5) times the standard amount (C1), and if it is “draft” and “weak penetration”, the standard amount 1.2 times (C2), if “draft” and “non-penetrating”, 1.1 (≈1.2 × 0.9) times the standard amount (C3), if “high definition” and “penetrating” 1.5 times the standard amount (C4), if “high definition” and “weak penetration”, the standard amount (1 time) (C5), if “high definition” and “non-penetration”, the standard amount 0.9 times (C6).

  Second, when the application is “indoor photo”, the amount of the polymerizable compound is set to the standard amount (1 time) (C7 to C12). Also, the polymerization initiator is increased or decreased according to the print mode and the recording medium type as already described with reference to FIG. 7 (C7 to C12).

  Third, as already described with reference to FIG. 7, when the usage is “indoor document”, the amount of the polymerizable compound is reduced as compared with the case of the standard condition (C11). For example, the amount of the polymerizable compound is 0.8 times the standard amount (C13 to C18). Also, the polymerization initiator is increased or decreased according to the print mode and the recording medium type as already described with reference to FIG. 7 (C13 to C18).

  Next, a correspondence relationship between the amounts of the polymerization initiator and the polymerizable compound in the determination table having the specific configuration illustrated in FIG. 9 and the ratio of the liquid amounts in the determination table having the basic configuration illustrated in FIG. 8 will be described.

  Using the table information 800 of the specific configuration shown in FIG. 9, the amounts of the polymerization initiator and the polymerizable compound corresponding to the output conditions (use, print mode and recording medium type) are obtained, and thereby the basic configuration shown in FIG. The liquid amount application ratio as shown in the table 80 is specified.

  For example, in the case of the first combination example of FIG. 5, based on the amount of the polymerization initiator and the polymerizable compound obtained using the determination table of FIG. The application ratio of the second liquid containing and the third liquid containing the polymerizable compound is obtained.

  In the case of the first combination example in FIG. 5, as already described, the second liquid contains a polymerizable compound, but the amount of the polymerizable compound contained in the second liquid is kept constant, The amount of the polymerizable compound is adjusted by adjusting the application amount of the three liquids according to the output conditions.

[Flow of liquid application control process]
Next, an example of the flow of the grant ratio control process will be described using the flowchart of FIG.

  First, various output conditions relating to the output (recording) of the recording medium 20 are detected (S10).

  Specifically, the use of the recording medium 20 is detected (S11), the printing mode is detected (S12), and the type of the recording medium 20 is detected (S13).

  Next, with reference to the table information (80 in FIG. 8 or 800 in FIG. 9) stored in advance in the memory 152 of FIG. 1, the liquid amount application ratio is controlled (S20).

  Specifically, referring to the table information, the liquid amount ratio corresponding to the output condition detected in step S10 is specified (S21), and the amount of liquid that is ejected for each nozzle 51 of each liquid discharge head 50 (striking) Droplet amount) is calculated (S22), and the drive waveform applied to the head driver 154 is controlled (S23).

  As a result, the liquid is applied to the recording medium at an application ratio corresponding to the output condition, and the UV light source 126 irradiates the recording medium 20 with ultraviolet rays, and a polymerization reaction (curing) occurs on the recording medium 20. Done.

  In addition, although the case where an ultraviolet-ray was used as an example was demonstrated as a radiation (radiation ray) which causes a polymerization reaction, this invention is not limited to this. For example, the present invention can also be applied when using an electron beam.

  Further, although the case where a liquid discharge head that discharges (droplets) liquid (droplets) is used as the liquid applying means for applying liquid to the recording medium has been described as an example, the present invention is not limited to this. For example, the liquid may be applied by applying it to a recording medium.

  Further, the case where the target to be fixed on the medium (fixing target) is a colorant has been described as an example, but the present invention is not limited to this. For example, the present invention can be applied to a case where a liquid containing a wiring material or a bonding material is fixed to a medium.

  As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to the example demonstrated by this specification, the numerical value, and the example illustrated by drawing, In the range which does not deviate from the summary of this invention, Of course, various design changes and improvements may be made.

1 is a block diagram illustrating an overall configuration example of an image forming apparatus as a liquid applying apparatus according to the present invention. It is a plane perspective view showing an outline of the whole structure about an example of a liquid discharge head. FIG. 3 is a cross-sectional view illustrating a part of the liquid ejection head in FIG. 2. It is a basic block diagram of the liquid provision part used for description of the example of a combination. It is explanatory drawing which shows the example of a combination of a liquid. FIG. 4 is a specific configuration diagram of a liquid applying unit including a liquid discharge head that discharges ink of each color of Y, M, C, and K. It is explanatory drawing used for description of the grant ratio control processing content. It is a figure which shows the table information of the basic composition used for a grant ratio control process. It is a figure which shows the table information of the specific structure used for a provision ratio control process. It is a flowchart which shows the outline of an example of the flow of a provision ratio control process.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Image forming apparatus (liquid application apparatus), 12 ... Liquid application part, 50 ... Liquid discharge head, 51 ... Nozzle (discharge port), 52 ... Pressure chamber, 53 ... Ink supply port, 54 ... Pressure chamber unit, 55 ... Common liquid chamber, 56 ... Vibration plate (common electrode of actuator), 57 ... Individual electrode of actuator, 58 ... Piezoelectric body of actuator, 110 ... Communication interface, 112 ... System controller, 114, 152 ... Memory, 126 ... UV light source, 132 ... Application detection unit, 134 ... Print mode detection unit, 136 ... Media type detection unit, 150 ... Print control unit (applying ratio control means)), 154 ... Head driver, 80, 800 ... Table information, 580 ... Actuator

Claims (8)

Liquid applying means for applying a plurality of types of liquid to a predetermined medium for recording;
The amount of liquid between a plurality of types of liquid applied to the medium according to the type of the medium, the printing mode indicating the printing mode of the medium, the use of the medium, or a combination thereof, or other output conditions of the medium Grant ratio control means for changing the ratio of
A liquid applicator characterized by comprising: Liquid applying means for applying to the medium a first liquid containing a polymerization initiator, a second liquid containing a polymerizable compound, and a third liquid containing a fixing target to be fixed to a predetermined medium by a polymerization reaction of the polymerizable compound. When,
Radiation irradiating means for irradiating the medium provided with the first liquid, the second liquid, and the third liquid;
Output condition detecting means for detecting the output condition of the medium;
Based on the detection result by the output condition detection means, at least two of the three liquids of the first liquid, the second liquid, and the third liquid applied to the medium by the liquid application means. An application ratio control means for controlling the ratio of the liquid amount between the liquids;
A liquid applicator characterized by comprising:   The third liquid includes the polymerizable compound, and the third liquid including the polymerizable compound and the fixing target to be fixed to the medium by a polymerization reaction of the polymerizable compound is applied to the medium by the liquid applying unit. The liquid application apparatus according to claim 2, wherein after the application, the second liquid containing the polymerizable compound is applied to the medium by the liquid application unit. A liquid applying means for applying a first liquid containing a polymerization initiator and a second liquid containing a polymerizable compound to a predetermined medium;
Radiation irradiating means for irradiating the medium to which the first liquid and the second liquid are applied;
Output condition detecting means for detecting the output condition of the medium;
An application ratio control unit that controls the ratio of the liquid amount of the first liquid applied to the medium by the liquid application unit and the liquid amount of the second liquid based on the detection result by the output condition detection unit. When,
A liquid applicator characterized by comprising:   5. The liquid applying apparatus according to claim 4, wherein any one of the first liquid and the second liquid includes a fixing target to be fixed to the medium by a polymerization reaction of the polymerizable compound.   The liquid application apparatus according to claim 2, wherein the fixing target is a colorant.   7. The output condition according to claim 2, wherein the output condition includes at least one of a type of the medium, a printing mode indicating a printing mode of the medium, and a use of the medium. Liquid applicator.   When recording by applying a plurality of types of liquids to a predetermined medium, the type of the medium, a printing mode indicating the printing mode of the medium, the use of the medium, or a combination thereof, and the output of the other medium A liquid application method characterized by changing a ratio of liquid amounts between a plurality of types of liquid applied to the medium according to conditions.

Images