JP5919634B2 - Inkjet drawing method - Google Patents

Description

  The present invention relates to an ink jet drawing method.

Conventionally, metal plating, foil press printing using a metal foil, thermal transfer using a metal foil, and the like have been used as a method for producing a decorative product exhibiting a glossy appearance.
However, these methods have a problem that it is difficult to form a fine pattern or to apply to a curved surface portion. In addition, foil stamp printing has a problem that gradation-like metallic printing cannot be performed.

On the other hand, as a recording method on a recording medium using a composition containing a pigment or a dye, a recording method using an inkjet method is used. The ink jet method is excellent in that it can be suitably applied to formation of a fine pattern and recording on a curved surface portion. In recent years, in the ink jet method, a composition that cures when irradiated with ultraviolet rays (ultraviolet curable ink jet composition) has been used in order to make the abrasion resistance, water resistance, solvent resistance, etc. particularly excellent. Yes (
For example, see Patent Document 1).

However, in UV-curable ink-jet inks, when metal powder is applied instead of pigments and dyes, characteristics such as glossiness (high brightness and lightness) inherent to the metal are sufficiently exhibited. In addition, there is a problem that it cannot be performed, and the contrast ratio in the portion to which the ink using the metal powder is applied cannot be sufficiently increased, and the design property cannot be sufficiently obtained.

JP 2009-57548 A

An object of the present invention is to provide an ink jet drawing method capable of easily forming a pattern having excellent gloss and design, and to provide a recorded matter having a pattern having excellent gloss and design. It is in.

Such an object is achieved by the present invention described below.
The inkjet drawing method of the present invention is an inkjet drawing method of forming a pattern using an ultraviolet curable inkjet composition containing metal particles and a polymerizable compound,
A recording medium preparation step of preparing a recording medium having a plurality of convex portions on the surface;
A composition application step of applying the ultraviolet curable inkjet composition to at least a part of the convex portion of the recording medium by an inkjet method;
And a polymerization step of polymerizing the polymerizable compound by irradiating with ultraviolet rays.
Thereby, the inkjet drawing method which can form easily the pattern excellent in glossiness and the designability can be provided.

In the inkjet drawing method of the present invention, the average height of the convex portions is 1.5 μm or more and 15 μm.
m or less is preferable.
As a result, light can be diffused and reflected more effectively on the surface of the recording medium, and a pattern with particularly excellent gloss and design can be formed.
In the ink jet drawing method of the present invention, the occupation ratio of the convex portions on the surface of the recording medium is preferably 15% or more and 65% or less.
As a result, light can be diffused and reflected more effectively on the surface of the recording medium, and a pattern with particularly excellent gloss and design can be formed.

In the inkjet drawing method of the present invention, the convex portion includes the polymerizable compound, and
It is preferably formed by discharging an ultraviolet curable ink containing no metal particles by an inkjet method.
Thereby, while making the adhesiveness of the composition for ultraviolet curable inkjets higher,
Glossiness and luxury can be made particularly excellent.

In the inkjet drawing method of the present invention, the convex portion is formed by discharging an ultraviolet curable ink containing a colorant and the polymerizable compound and not containing metal particles by an inkjet method. preferable.
As a result, the gloss and luxury can be further improved.
In the ink jet drawing method of the present invention, it is preferable that the metal particles include scaly aluminum.
Thereby, it is possible to more easily form a pattern particularly excellent in glossiness and design.

In the inkjet drawing method of the present invention, it is preferable that the ultraviolet curable inkjet composition contains phenoxyethyl acrylate as the polymerizable compound.
As a result, the storage stability of the ultraviolet curable ink jet composition is excellent, while the reactivity of the ultraviolet curable ink jet composition after ejection by the ink jet method is particularly excellent, and the productivity of recorded matter is improved. In addition to being particularly excellent, it is possible to make the formed pattern particularly excellent in abrasion resistance and the like. Further, the metal particles can be arranged more suitably, and the glossiness and high-quality feeling of the recorded matter can be made particularly excellent.

In the ink-jet drawing method of the present invention, the ultraviolet curable ink-jet composition contains, as the polymerizable compound, 2- (2 acrylic acid in addition to the phenoxyethyl acrylate.
-Vinyloxyethoxy) ethyl, dipropylene glycol diacrylate, tripropylene glycol diacrylate, and at least one selected from the group consisting of 4-hydroxybutyl acrylate are preferable.

As a result, the storage stability of the ultraviolet curable ink jet composition is excellent, while the reactivity of the ultraviolet curable ink jet composition after ejection by the ink jet method is particularly excellent, and the productivity of recorded matter is improved. In addition to being particularly excellent, it is possible to make the formed pattern particularly excellent in abrasion resistance and the like. Further, the metal particles can be arranged more suitably, and the glossiness and high-quality feeling of the recorded matter can be made particularly excellent.

In the ink jet drawing method of the present invention, it is preferable that the ultraviolet ray curable ink jet composition contains dimethylol tricyclodecane diacrylate and / or amino acrylate as the polymerizable compound.
As a result, the storage stability of the ultraviolet curable inkjet composition can be further improved, and the scratch resistance of the pattern to be formed can be further improved. Further, the metal particles can be arranged more suitably, and the glossiness and high-quality feeling of the recorded matter can be made particularly excellent.
The recorded matter of the present invention includes a pattern drawn by using the method of the present invention.
Thereby, the recorded matter provided with the pattern excellent in glossiness and designability can be provided.

It is a perspective view which shows the droplet discharge apparatus used for manufacture of a recorded matter. It is a top view which shows an example of the pattern (printing part) formed in a recorded matter. It is a top view which shows an example of the pattern (printing part) formed in a recorded matter.

Hereinafter, preferred embodiments of the present invention will be described in detail.
<Inkjet drawing method>
First, the ink jet drawing method of the present invention will be described.
FIG. 1 is a perspective view illustrating a droplet discharge device used for manufacturing a recorded material, and FIGS. 2 and 3 are plan views illustrating an example of a pattern (printing unit) formed on the recorded material.

In the inkjet drawing method of the present invention, a recording medium preparation step (1a) for preparing a recording medium having a plurality of convex portions on the surface, and an ultraviolet curable inkjet composition containing metal particles and a polymerizable compound are prepared by an inkjet method. It has the composition provision process (1b) provided to at least one part of the convex part on a recording medium, and the superposition | polymerization process (1c) which superposes | polymerizes the said polymeric compound by irradiating an ultraviolet-ray.

By the way, conventionally, metal plating, foil press printing using a metal foil, thermal transfer using a metal foil, and the like have been used as a method for producing a decorative product exhibiting a glossy appearance.
However, these methods have a problem that it is difficult to form a fine pattern or to apply to a curved surface portion. In addition, foil stamp printing has a problem that gradation-like metallic printing cannot be performed.

On the other hand, as a recording method on a recording medium using a composition containing a pigment or a dye, a recording method using an inkjet method is used. The ink jet method is excellent in that it can be suitably applied to formation of a fine pattern and recording on a curved surface portion. In recent years, compositions that cure when irradiated with ultraviolet rays (ultraviolet curable inkjet compositions) have been used in the ink jet method in order to achieve particularly excellent abrasion resistance, water resistance, solvent resistance, and the like. ing.

However, in UV-curable ink-jet inks, when metal powder is applied instead of pigments and dyes, characteristics such as glossiness (high brightness and lightness) inherent to the metal are sufficiently exhibited. In addition, there is a problem that it cannot be performed, and the contrast ratio in the portion to which the ink using the metal powder is applied cannot be sufficiently increased, and the design property cannot be sufficiently obtained.

On the other hand, the present invention is characterized in that the ultraviolet curable ink jet composition is applied to at least a part of the convex portion of the recording medium having a plurality of convex portions on the surface. In addition, irregular reflection of light can be effectively generated on the surface of the recording medium on which a pattern is formed by the ultraviolet curable ink jet composition. As a result, excellent gloss and design can be expressed on the recording medium.

<Recording medium preparation process>
First, a recording medium 11 having a plurality of convex portions 3 on the surface is prepared (1a).
The recording medium 11 is not particularly limited, and any of absorptive or nonabsorptive may be used. For example, paper (plain paper, inkjet dedicated paper, etc.), plastic material, metal, ceramics, wood, shells, etc. Can be used. In particular, synthetic materials with high smoothness such as polyethylene terephthalate, polycarbonate, polypropylene, and polyethylene, synthetic paper such as YUPO (registered trademark of YUPO Corporation), and mirror surface printing paper such as cast coated paper are more used. preferable.

A method for forming the convex portion 3 is not particularly limited, but it is preferable to form the convex portion 3 by applying ink containing a material for forming the convex portion 3 to the recording medium 11. Thereby, it is possible to more easily form any number of convex portions 3 having any shape at any position.
The ink used for forming the convex portion 3 is not particularly limited, but includes an ultraviolet curable ink that contains a polymerizable compound that constitutes an ultraviolet curable inkjet composition described later and does not contain a metal material. Is preferably used. Thereby, while making the adhesiveness of the ultraviolet curable inkjet composition higher, glossiness and luxury can be made particularly excellent.

Further, the ultraviolet curable ink used to form the convex portion 3 may contain a colorant. As a result, the gloss and luxury can be further improved.
Moreover, it does not specifically limit as a shape of the convex part 3, For example, a stripe shape (line shape) may be sufficient and a dot shape may be sufficient.
Further, the average height of the protrusions 3 is preferably 1.5 μm or more and 15 μm or less, and preferably 2 μm.
More preferably, it is 10 μm or less. As a result, light can be diffusely reflected more effectively on the surface of the recording medium 11, and a pattern having particularly excellent gloss and design can be formed.
Further, the occupation ratio of the protrusions 3 on the surface of the recording medium is preferably 15% or more and 65% or less, and more preferably 20% or more and 60% or less. As a result, light can be diffusely reflected more effectively on the surface of the recording medium 11, and a pattern having particularly excellent gloss and design can be formed.

<Composition application process>
Next, an ultraviolet curable inkjet composition 2 containing metal particles and a polymerizable compound,
It is applied to a part of the convex portion 3 of the recording medium 11 by an ink jet method (1b).
The ultraviolet curable inkjet composition 2 may be applied to the convex portion 3 at least on a part of the convex portion, for example, as shown in FIG. And
As shown in FIG. 3, you may provide symmetrically on the surface of a convex part.

As an ink jet method (droplet discharge method), for example, a piezo method or a method in which ink is discharged by bubbles generated by heating the ink can be used. The piezo method is preferable from the viewpoint of the difficulty of alteration of the product 2.
In the following description, it is assumed that the ultraviolet curable inkjet composition is discharged using a droplet discharge device as shown in FIG.

As shown in FIG. 1, a droplet discharge device 100 used in this step includes a tank 101 that holds an ultraviolet curable ink composition 2, a tube 110, and an ultraviolet curable ink jet from the tank 101 via the tube 110. And a discharge scanning unit 102 to which the composition 2 is supplied. The ejection scanning unit 102 controls a position of the droplet ejection unit 103 and a droplet ejection unit 103 having a plurality of droplet ejection heads (inkjet heads) mounted on the carriage.
A position control device 104 (moving means), a stage 106 that holds the recording medium (base material) 11, a second position control device 108 (moving means) that controls the position of the stage 106, and the control means 1
12. The tank 101 and a plurality of droplet discharge heads in the droplet discharge means 103 are connected by a tube 110, and the ultraviolet curable inkjet composition 2 is compressed air from the tank 101 to each of the plurality of droplet discharge heads. Supplied by

The first position control device 104 responds to a signal from the control means 112 in accordance with the droplet discharge means 103.
Are moved along the X-axis direction and the Z-axis direction orthogonal to the X-axis direction. Further, the first position control device 104 also has a function of rotating the droplet discharge means 103 around an axis parallel to the Z axis. In the present embodiment, the Z-axis direction is a direction parallel to the vertical direction (that is, the direction of gravitational acceleration). The second position controller 108 moves the stage 106 along the Y-axis direction orthogonal to both the X-axis direction and the Z-axis direction in response to a signal from the control unit 112. In addition, the second
The position control device 108 also has a function of rotating the stage 106 around an axis parallel to the Z axis.

The stage 106 has a plane parallel to both the X-axis direction and the Y-axis direction. The stage 106 is configured so that the recording medium 11 to which the ultraviolet curable ink jet composition 2 is to be applied can be fixed or held on the plane.
As described above, the droplet discharge means 103 is moved in the X-axis direction by the first position control device 104. On the other hand, the stage 106 is moved in the Y-axis direction by the second position control device 108. That is, the first position control device 104 and the second position control device 108 change the relative position of the droplet discharge head with respect to the stage 106 (the recording medium 11 held on the stage 106 and the droplet discharge means 103 are relative to each other). To go to).

The control means 112 is configured to receive ejection data representing a relative position at which the ultraviolet curable inkjet composition 2 is to be ejected from an external information processing apparatus.
The ultraviolet curable inkjet composition 2 is applied to the recording medium 11 using the droplet discharge device 100 as described above. By using the apparatus as described above, the ultraviolet curable inkjet composition 2 can be efficiently and selectively applied to a desired portion of the recording medium 11. In the configuration shown in the figure, the droplet discharge device 100 has only one color of the tank 101, the tube 110, and the like for holding the ultraviolet curable ink jet composition 2, but these members are provided with a plurality of types. You may have only the part for the composition 2 for ultraviolet curable inkjets. In the production of recorded matter, a plurality of droplet discharge devices 100 corresponding to a plurality of types of ultraviolet curable inkjet compositions 2 may be used.

In the present invention, the droplet discharge head may use a piezo element or an electrostatic actuator as a drive element. In addition, the droplet discharge head may be configured to use an electrothermal conversion element as a drive element and to discharge the ultraviolet curable ink jet composition using the thermal expansion of the material by the electrothermal conversion element.
The ultraviolet curable ink jet composition will be described in detail later.

<Polymerization process>
Thereafter, by irradiating with ultraviolet rays, the polymerizable compound constituting the ultraviolet curable inkjet composition 2 applied to the recording medium 11 is cured to obtain a printed part (pattern) (1c).
). Thereby, a recorded matter is obtained.
As the ultraviolet light source, for example, a mercury lamp, a metal halide lamp, an ultraviolet light emitting diode (UV-LED), an ultraviolet laser diode (UV-LD), or the like can be used.
Among these, from the viewpoint of small size, long life, high efficiency, and low cost, an ultraviolet light emitting diode (UV-L
ED) and ultraviolet laser diodes (UV-LD) are preferred.
In addition, you may perform this process, making a magnetic force act. This makes it possible to cure the ultraviolet curable inkjet composition 2 without disturbing the arrangement state of the powder arranged in the arrangement step, and to make the gloss of the recorded matter particularly surely excellent. Can do.

<< UV-curable inkjet composition >>
Hereinafter, the ultraviolet curable inkjet composition used in the present invention will be described in detail.
<Metal particles>
As described above, the ultraviolet curable ink jet composition contains metal particles (metal powder). In this specification, the metal particle means a particle having at least a surface made of a metal material.

Although it does not specifically limit as a metal material which comprises a metal particle, It is preferable to use aluminum. Thereby, the powder can be more suitably arranged in the finally obtained recorded matter. In addition, aluminum generally has a particularly excellent metallic luster. Therefore, when the metal particles are composed of aluminum, the gloss and high quality of the recorded matter can be made particularly excellent.
The metal particles may have any shape such as a circular shape, an elliptical shape, a needle shape, and a scale shape, but a scale shape is preferable. Thereby, the metal particles constituting the ultraviolet curable ink jet composition can be more suitably arranged on the recording medium, and the glossiness of the formed pattern can be further improved.

In the present invention, the scale shape is an area when the area when observed from a predetermined angle (when viewed in plan) is observed from an angle orthogonal to the observation direction, such as a flat plate shape or a curved plate shape. In particular, the area S ₁ [μm ² ] when observed from the direction in which the projected area is maximum (when viewed in plan) and the direction orthogonal to the observation direction are observed. The ratio (S ₁ / S ₀ ) with respect to the area S ₀ [μm ² ] when observed from the direction in which the area of the area becomes maximum is preferably 2 or more, more preferably 5 or more, and still more preferably 8 or more. It is. As this value, for example, it is possible to observe an arbitrary 10 particles and adopt an average value of values calculated for these particles.

The scale-like metal particles may be produced by any method, but can be obtained by forming a film composed of metal by a vapor deposition method and then crushing the film. It is preferable that Thereby, the glossiness etc. which a metal originally has in the pattern formed using an ultraviolet curable inkjet composition can be expressed more effectively. Moreover, the dispersion | variation in the characteristic between each metal particle can be suppressed.

When producing metal particles using such a method, for example, metal particles can be suitably produced by forming a film made of metal (film formation) on a substrate. As the substrate, for example, a plastic film such as polyethylene terephthalate can be used. Further, the substrate may have a release agent layer on the film forming surface.
Moreover, it is preferable that the said grinding | pulverization is performed by providing an ultrasonic vibration to the said film | membrane in a liquid. Thereby, the first particles having the above-described particle diameter can be obtained easily and reliably, and the occurrence of variations in size, shape, and characteristics among the particles can be suppressed.

When the pulverization is performed by the above method, the liquid includes alcohols such as methanol, ethanol, propanol, and butanol, n-heptane, n-octane, decane, dodecane, tetradecane, toluene, xylene, and cymene. Hydrocarbon compounds such as durene, indene, dipentene, tetrahydronaphthalene, decahydronaphthalene, cyclohexylbenzene, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether , 1,2-dimethoxyethane, bis (2-methoxyethyl) ether, p-dioxane and the like ether compounds Propylene carbonate, γ- butyrolactone,
Polar compounds such as N-methyl-2-pyrrolidone, N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMA), dimethyl sulfoxide, cyclohexanone and acetonitrile can be preferably used. By using such a liquid, while preventing unintentional oxidation of the metal particles, the productivity of the metal particles is particularly excellent,
Variations in size, shape, and characteristics among the metal particles can be made particularly small.

When the metal particles are scaly, the average thickness of the metal particles is preferably 5 nm or more and 250 nm or less, and more preferably 10 nm or more and 150 nm or less. When the average thickness of the metal particles is a value within the above range, the storage property of the ultraviolet curable inkjet composition and the discharge stability of the droplets are particularly excellent, while the metal originally has in the pattern. The glossiness and the like can be expressed more effectively.

The average particle size of the metal particles is preferably 500 nm or more and 2.0 μm or less, and 8
More preferably, it is 00 nm or more and 1.8 μm or less. Thereby, in the pattern (printing part) formed using the ultraviolet curable ink-jet composition, the metal particles can be arranged more reliably and reliably, and the pattern formed using the ultraviolet curable ink-jet composition ( The glossiness of the printing part) can be further improved. In the present invention, the average particle diameter refers to the average particle diameter based on the number, and the average of the diameters of perfect circles having the same area as the area S ₁ when observed from the direction in which the projected area is maximized. Refers to the value.

<Polymerizable compound>
The ultraviolet curable ink jet composition includes a polymerizable compound that is a component that is polymerized and cured by irradiation with ultraviolet rays. By including such a component, it is possible to improve the abrasion resistance, water resistance, solvent resistance, and the like of the recorded matter produced using the ultraviolet curable ink jet composition. Moreover, since the metal particles arranged (orientated) as described above can be fixed by curing the polymerizable compound, the glossiness of the recorded matter can be stably improved.

The polymerizable compound is in a liquid state and preferably functions as a dispersion medium for dispersing the powder in the ultraviolet curable ink jet composition. As a result,
It is not necessary to use a dispersion medium that is removed (evaporated) in the production process of recorded matter, and it is not necessary to provide a process for removing the dispersion medium in the production of recorded matter. It can be. Moreover, since it is not necessary to use what is generally used as an organic solvent as a dispersion medium, generation | occurrence | production of the problem of a volatile organic compound (VOC) can be prevented. Moreover, the adhesiveness of the printing part formed using the ultraviolet curable inkjet composition with respect to various recording media (base materials) can be made excellent by including a polymeric compound. That is, by including the polymerizable compound, the ultraviolet curable inkjet composition has excellent media compatibility.

As the polymerizable compound, any component that can be polymerized by irradiation with ultraviolet rays can be used. For example, various monomers, various oligomers (including dimers, trimers, etc.) can be used.
The ultraviolet curable ink jet composition preferably contains at least a monomer component as a polymerizable compound. Since the monomer is generally a component having a low viscosity as compared with the oligomer component or the like, it is advantageous for making the ejection stability of the ultraviolet curable inkjet composition particularly excellent.

Examples of the monomer as the polymerizable compound include isobornyl acrylate, 4-hydroxybutyl acrylate, lauryl acrylate, 2-methoxyethyl acrylate,
Phenoxyethyl acrylate, isooctyl acrylate, stearyl acrylate,
Cyclohexyl acrylate, 2-ethoxyethyl acrylate, benzyl acrylate, 1H, 1H, 5H-octafluoropentyl acrylate, 1H, 1H, 5H-octafluoropentyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, isobutyl acrylate, t-butyl acrylate, tetrahydrofurfuryl acrylate, ethyl carbitol acrylate, 2,2,2-trifluoroethyl acrylate, 2,2,2-trifluoroethyl methacrylate, 2,2,
3,3-tetrafluoropropyl acrylate, methoxytriethylene glycol acrylate, methoxytriethylene glycol acrylate, PO-modified nonylphenol acrylate, EO-modified nonylphenol acrylate, EO-modified 2-ethylhexyl acrylate, EO-modified nonylphenol acrylate, phenylglycidyl ether acrylate, phenoxydiethylene glycol acrylate EO-modified phenol acrylate,
Phenoxyethyl acrylate, EO-modified phenol acrylate, EO-modified cresol acrylate, methoxypolyethylene glycol acrylate, dipropylene glycol acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, 2-n-butyl-2-ethyl-1,3- Propanediol diacrylate, tripropylene glycol diacrylate, tetraethylene glycol diacrylate, 1
. 9-nonanediol diacrylate, 1,4-butanediol diacrylate, bisphenol A EO modified diacrylate, 1.6-hexanediol diacrylate, polyethylene glycol 200 diacrylate, polyethylene glycol 300 diacrylate, neopentyl glycol hydroxypiparate Diacrylate, 2-ethyl-2-butyl-propanediol diacrylate, polyethylene glycol 400 diacrylate, polyethylene glycol 600 diacrylate, polypropylene glycol diacrylate, 1.9-nonanediol diacrylate, 1.6-hexanediol diacrylate Bisphenol A EO modified diacrylate, bisphenol A EO modified diacrylate, bisphenol A EO modified Diacrylate, PO-modified bisphenol A diacrylate, EO-modified hydrogenated bisphenol A diacrylate, dipropylene glycol diacrylate, polypropylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, trimethylolpropane EO modified triacrylate, glycerin PO-added triacrylate, trisacryloyloxyethyl phosphate, pentaerythritol tetraacrylate, PO-modified trimethylolpropane triacrylate, PO-modified trimethylolpropane triacrylate, tris (acryloxyethyl) isocyanurate, pentaerythritol triacrylate,
Examples include trimethylolpropane triacrylate, pentaerythritol triacrylate, and 2- (2-vinyloxyethoxy) ethyl acrylate. Among them, 4-hydroxybutyl acrylate, phenoxyethyl acrylate, phenoxyethyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, tripropylene glycol diacrylate, tetraethylene glycol diacrylate, dipropylene glycol diacrylate, trimethylolpropane tri Preferred are acrylate, trimethylolpropane EO-modified triacrylate, pentaerythritol tetraacrylate, pentaerythritol triacrylate, and 2- (2-vinyloxyethoxy) ethyl acrylate.

In particular, the ultraviolet curable ink jet composition preferably contains phenoxyethyl acrylate as the polymerizable compound. As a result, the storage stability of the ultraviolet curable ink jet composition is excellent, while the reactivity of the ultraviolet curable ink jet composition after ejection by the ink jet method is particularly excellent, and the productivity of recorded matter is improved. In addition to being particularly excellent, it is possible to make the formed pattern particularly excellent in abrasion resistance and the like. Further, the metal particles can be arranged more suitably, and the glossiness and high-quality feeling of the recorded matter can be made particularly excellent.

In addition to the phenoxyethyl acrylate, the ultraviolet curable ink jet composition includes 2- (2-vinyloxyethoxy) ethyl acrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, and 4 as a polymerizable compound. −
It is preferable that it contains at least one selected from the group consisting of hydroxybutyl acrylate. As a result, the storage stability of the ultraviolet curable ink jet composition is excellent, while the reactivity of the ultraviolet curable ink jet composition after ejection by the ink jet method is particularly excellent, and the productivity of recorded matter is improved. In addition to being particularly excellent, it is possible to make the formed pattern particularly excellent in abrasion resistance and the like. Further, the metal particles can be arranged more suitably, and the glossiness and high-quality feeling of the recorded matter can be made particularly excellent.

Moreover, it is preferable that the ultraviolet curable inkjet composition contains dimethylol tricyclodecane diacrylate and / or amino acrylate as the polymerizable compound.
As a result, the storage stability of the ultraviolet curable inkjet composition can be further improved, and the scratch resistance of the pattern to be formed can be further improved. Further, the metal particles can be arranged more suitably, and the glossiness and high-quality feeling of the recorded matter can be made particularly excellent.

Moreover, the ultraviolet curable ink jet composition may contain an oligomer in addition to the monomer as the polymerizable compound. In particular, those containing polyfunctional oligomers are preferred. As a result, the storage stability of the ultraviolet curable ink-jet composition can be made excellent, and the abrasion resistance of the formed pattern can be made particularly excellent. In the present invention, among polymerizable compounds, the compound has a repeating structure in the skeleton of the molecule and has a molecular weight of 600.
The above is called an oligomer. As the oligomer, a urethane oligomer whose repeating structure is urethane, an epoxy oligomer whose repeating structure is epoxy, and the like are preferably used.

<Other ingredients>
The ultraviolet curable inkjet composition according to the present embodiment may contain components other than those described above (other components). Such components include, for example, photopolymerization initiators, slip agents (leveling agents), dispersants, polymerization accelerators, polymerization inhibitors, penetration enhancers, wetting agents (humectants), colorants, fixing agents, anti-blocking agents. Examples include glazes, preservatives, antioxidants, chelating agents, thickeners, and sensitizers (sensitizing dyes).

The photopolymerization initiator is not particularly limited as long as it generates active species such as radicals and cations by ultraviolet irradiation and initiates the polymerization reaction of the polymerizable compound. As the photopolymerization initiator, a radical photopolymerization initiator or a cationic photopolymerization initiator can be used, but it is preferable to use a radical photopolymerization initiator. When using a photopolymerization initiator, the photopolymerization initiator preferably has an absorption peak in the ultraviolet region.

Examples of the photo radical polymerization initiator include aromatic ketones, acylphosphine oxide compounds, aromatic onium salt compounds, organic peroxides, thio compounds (thioxanthone compounds, thiophenyl group-containing compounds, etc.), hexaarylbiimidazole compounds, Examples thereof include ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having a carbon halogen bond, and alkylamine compounds.
Among these, at least one selected from an acylphosphine oxide compound and a thioxanthone compound is preferable from the viewpoint of solubility in a polymerizable compound and curability, and it is more preferable to use an acylphosphine oxide compound and a thioxanthone compound in combination.

Specific examples of the photo radical polymerization initiator include acetophenone, acetophenone benzyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine. , Carbazole, 3-methylacetophenone, 4-chlorobenzophenone, 4,4′-dimethoxybenzophenone, 4,4′-diaminobenzophenone, Michler's ketone, benzoin propyl ether, benzoin ethyl ether, benzyldimethyl ketal, 1- (4-isopropylphenyl) ) -2-hydroxy-2-methylpropan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, thioxanthone, diethylthio Xanthone, 2-isopropylthioxanthone, 2-
Chlorothioxanthone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6 -Trimethylbenzoyl-diphenyl-phosphine oxide, 2,4-diethylthioxanthone, bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, etc. These can be used alone or in combination of two or more.

The content of the photopolymerization initiator in the ultraviolet curable inkjet composition is preferably 0.5% by mass or more and 10% by mass or less. When the content of the photopolymerization initiator is within the above range,
The UV curing rate is sufficiently high, and the photopolymerization initiator is not dissolved and there is almost no color derived from the photopolymerization initiator.
When the ultraviolet curable ink jet composition contains a slip agent, the surface of the recorded matter becomes smooth due to the leveling action, and the abrasion resistance is improved.

Although it does not specifically limit as a slip agent, For example, silicone type surfactants, such as polyester modified silicone and polyether modified silicone, can be used, It is preferable to use polyether modified polydimethylsiloxane or polyester modified polydimethylsiloxane. .
When the ultraviolet curable ink jet composition contains a dispersant, the metal particles can have excellent dispersibility, and the ultraviolet curable ink jet composition has particularly excellent storage stability and ejection stability. It can be. The dispersant is not particularly limited,
For example, polyoxyalkylene polyalkylene polyamine, vinyl polymer and copolymer, acrylic polymer and copolymer, polyester, polyamide, polyimide, polyurethane, amino polymer, silicon-containing polymer, sulfur-containing polymer, fluorine-containing polymer, epoxy resin, etc. It is done.

Moreover, it is preferable that the ultraviolet curable inkjet composition does not contain an organic solvent that is removed (evaporates) in the manufacturing process of the recorded matter. Thereby, generation | occurrence | production of the problem of a volatile organic compound (VOC) can be prevented effectively.
The viscosity at room temperature (20 ° C.) of the ultraviolet curable inkjet composition used in the present invention is 2
It is preferably 0 mPa · s or less, and more preferably 3 mPa · s or more and 15 mPa · s or less. Thereby, the droplet discharge by an inkjet method can be performed suitably.

《Recordings》
Next, the recorded matter of the present invention will be described.
The recorded matter of the present invention has a pattern formed by using the method as described above. Such a recorded matter has a pattern (pattern) excellent in glossiness and design.

Further, as described above, the ultraviolet curable ink jet composition according to the present invention contains a polymerizable compound and has excellent adhesion to a recording medium.
The recorded matter of the present invention may be used for any purpose, and may be applied to, for example, a decorative article or other items. Specific examples of the recorded matter of the present invention include a console lid,
Display items such as switch bases, center clusters, interior panels, emblems, center consoles, meter nameplates, and other vehicle interior parts, various electronic device operation parts (key switches), decorative parts, indicators, logos, etc. Etc.
As mentioned above, although this invention was demonstrated based on suitable embodiment, this invention is not limited to these.

DESCRIPTION OF SYMBOLS 11 ... Recording medium (base material) 2 ... Composition for ultraviolet curable inkjet 3 ... Convex part 10
DESCRIPTION OF SYMBOLS 0 ... Droplet discharge apparatus 101 ... Tank 102 ... Discharge scanning part 103 ... Droplet discharge means 10
DESCRIPTION OF SYMBOLS 4 ... 1st position control apparatus (moving means) 106 ... Stage 108 ... 2nd position control apparatus (moving means) 110 ... Tube 112 ... Control means

Claims (9)

An inkjet drawing method for forming a pattern using an ultraviolet curable inkjet composition comprising metal particles and a polymerizable compound,
A recording medium preparation step of preparing a recording medium having a convex portion for irregularly reflecting a plurality of lights on the surface;
A composition application step of applying the ultraviolet curable inkjet composition to at least a part of the convex portion of the recording medium by an inkjet method;
And a polymerization step of polymerizing the polymerizable compound by irradiating with ultraviolet rays.   The inkjet drawing method according to claim 1, wherein an average height of the convex portions is 1.5 μm or more and 15 μm or less.   The inkjet drawing method according to claim 1, wherein an occupation ratio of the convex portions on the surface of the recording medium is 15% or more and 65% or less.   4. The ink jet drawing according to claim 1, wherein the convex portion is formed by discharging an ultraviolet curable ink containing the polymerizable compound and not containing metal particles by an ink jet method. 5. Method.   The said convex part is formed by discharging the ultraviolet curing ink which contains a coloring agent and the said polymeric compound, and does not contain a metal particle by an inkjet system. The inkjet drawing method as described in any one of.   The ink jet drawing method according to claim 1, wherein the metal particles include scaly aluminum.   The inkjet drawing method according to any one of claims 1 to 6, wherein the ultraviolet curable inkjet composition contains phenoxyethyl acrylate as the polymerizable compound.   In addition to the phenoxyethyl acrylate, the ultraviolet curable inkjet composition includes 2- (2-vinyloxyethoxy) ethyl acrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, and 4 as the polymerizable compound. The inkjet drawing method according to claim 7, comprising at least one selected from the group consisting of -hydroxybutyl acrylate.   The inkjet drawing method according to any one of claims 1 to 8, wherein the ultraviolet curable inkjet composition contains dimethylol tricyclodecane diacrylate and / or amino acrylate as the polymerizable compound.

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