Coloring composition and coloring method

Abstract

To provide a coloring composition that can be suitably applied to produce a colored body having an excellent glossy feeling as well as excellent adhesion between an object to which the coloring composition is given and a colored portion formed by the coloring composition; and to provide a coloring method that can be suitably applied to produce a colored body having an excellent glossy feeling as well as excellent adhesion of the colored portion.SOLUTION: A coloring composition of the present disclosure includes: a metal pigment; an acrylic-based resin having an acid value of 200 mgKOH / g or less; and a liquid medium component, wherein the metal pigment includes metal particles, the metal particles are surface-modified with a surface treatment agent, and the surface treatment agent includes at least one selected from the group consisting of a compound represented by the following formula (1): (RO)aP(O)(OH)3-a and a compound represented by the following formula (2): (R)aP(O)(OH)3-a.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to a coloring composition and a coloring method. [Background technology]

[0002] Traditionally, methods such as metal plating, foil stamping using metal foil, and heat transfer using metal foil have been used to manufacture decorative items that have a glossy appearance. However, these methods had drawbacks, such as being difficult to apply to curved surfaces.

[0003] On the other hand, compositions containing pigments or dyes are used as inkjet inks or coatings applied to recording media by inkjet technology. This method is advantageous in that it can be suitably applied to curved surfaces.

[0004] However, simply applying metal particles instead of pigments or dyes presented a problem: it was not possible to fully utilize the inherent properties of the metal, such as its luster.

[0005] To solve the above-mentioned problems, it has been proposed to use metal particles surface-treated with a fluorine-based compound (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2015-189775 [Overview of the project] [Problems that the invention aims to solve]

[0007] Although the gloss of the colored portion to which the composition is applied is improved to some extent, there was a problem in that the adhesion between the workpiece to which the composition is applied and the colored portion formed using the composition could not be made sufficiently good. [Means for solving the problem]

[0008] This invention was made to solve the above-mentioned problems and can be realized in the following application examples.

[0009] The coloring composition according to the application example of the present invention contains a metal pigment, an acrylic resin with an acid value of 200 mgKOH / g or less, and a liquid medium component. The aforementioned metal pigment consists of a plurality of metal particles, The aforementioned metal particles are surface-modified with a surface treatment agent. The surface treatment agent comprises at least one compound selected from the group consisting of compounds represented by the following formula (1) and compounds represented by the following formula (2). (RO) a P(O)(OH) 3-a (1) (R) a P(O)(OH) 3-a (2) (In the formula, R is a hydrocarbon group having 1 or more carbon atoms, and a is 1 or 2.)

[0010] Furthermore, in a coloring composition according to another application example of the present invention, R is a hydrocarbon group having 10 to 30 carbon atoms.

[0011] Furthermore, in the coloring compositions according to other applications of the present invention, the acid value of the acrylic resin is 1 mg KOH / g or more and 100 mg KOH / g or less.

[0012] Furthermore, in the coloring compositions according to other applications of the present invention, the weight-average molecular weight of the acrylic resin is 5,000 or more and 20,000 or less.

[0013] In addition, in the coloring composition according to another application example of the present invention, the proportion of the acrylic monomer in the acrylic resin is 90% by mass or more.

[0014] In addition, the coloring composition according to another application example of the present invention is a solvent-based composition containing an organic solvent as the liquid medium component.

[0015] In addition, in the coloring composition according to another application example of the present invention, the metal particles are made of aluminum or an aluminum alloy.

[0016] In addition, in the coloring composition according to another application example of the present invention, the metal particles are in a flaky shape.

[0017] In addition, in the coloring composition according to another application example of the present invention, the content of the surface treatment agent is 1.0 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the metal particles.

[0018] In addition, in the coloring composition according to another application example of the present invention, the coloring composition is an inkjet ink composition.

[0019] In addition, the coloring method according to the application example of the present invention includes a step of attaching the coloring composition according to the application example of the present invention to an adherent. In particular, it includes a step of discharging a coloring composition, which is an inkjet ink composition, by an inkjet method and attaching it to an adherent writing body, which is a recording medium. <I

Embodiments for Carrying Out the Invention

[0020] Hereinafter, preferred embodiments of the present invention will be described in detail. [1] Coloring Composition First, the coloring composition of the present invention will be described.

[0021] By the way, conventionally, as a method for manufacturing a decorative article having a glossy appearance, metal plating, foil stamping using a metal foil, heat transfer using a metal foil, etc. have been used.

[0022] However, these methods had drawbacks, such as being difficult to apply to curved surfaces.

[0023] On the other hand, compositions containing pigments or dyes are used as inkjet inks or coatings applied to recording media by inkjet technology. This method is advantageous in that it can be suitably applied to curved surfaces.

[0024] However, simply applying metal particles instead of pigments or dyes presented a problem: it was not possible to fully utilize the inherent properties of the metal, such as its luster.

[0025] To solve the above-mentioned problems, it has been proposed to use metal particles surface-treated with a fluorine-based compound. While this improves the dispersibility of the metal particles in the composition to some extent, there was a problem in that the adhesion between the object to which the composition is applied and the colored portion formed using the composition could not be sufficiently good.

[0026] Therefore, the inventor diligently conducted research with the aim of solving the above-mentioned problems, and as a result arrived at the present invention. Specifically, the coloring composition of the present invention contains a metal pigment, an acrylic resin with an acid value of 200 mg KOH / g or less, and a liquid medium component, wherein the metal pigment consists of a plurality of metal particles, and the metal particles are surface-modified with a surface treatment agent, and the surface treatment agent contains at least one selected from the group consisting of the compound represented by the following formula (1) and the compound represented by the following formula (2).

[0027] (RO) a P(O)(OH) 3-a (1) (R) a P(O)(OH) 3-a (2) (In the formula, R is a hydrocarbon group having 1 or more carbon atoms, and a is 1 or 2.)

[0028] This makes it possible to provide a coloring composition that is suitable for producing colored objects that have excellent dispersion stability of metal particles, excellent gloss, and excellent adhesion between the treated object to which the coloring composition is applied and the colored portion formed by the coloring composition. Furthermore, since there is no need to use fluorine-based surface treatment agents, it is also advantageous from an environmental standpoint.

[0029] Furthermore, the drying properties of the coloring composition coating can be improved, and for example, even when colored objects manufactured using the coloring composition are stacked, the occurrence of transfer to the back can be effectively prevented.

[0030] Furthermore, if the coloring composition is an inkjet ink composition applied to ejection by the inkjet method, in addition to the effects described above, it is possible to enjoy the benefits of applying the inkjet method, such as being able to more favorably form fine patterns and having excellent on-demand capabilities. In addition, the droplet ejection stability of the inkjet ink composition can be improved relatively shortly after manufacturing, and the droplet ejection stability can also be improved even when the inkjet ink composition is stored for a long period of time or under harsh conditions.

[0031] Conversely, if the above conditions are not met, satisfactory results cannot be obtained. For example, if the coloring composition does not contain an acrylic resin, or if another resin is used instead of an acrylic resin, it may not be possible to achieve sufficiently good adhesion between the workpiece to which the coloring composition is applied and the colored portion formed by the coloring composition. Furthermore, depending on the type of resin used instead of the acrylic resin, problems may arise such as a significant decrease in the dispersion stability of metal particles in the coloring composition or a significant decrease in the glossiness of the colored product manufactured using the coloring composition.

[0032] Furthermore, even if the coloring composition contains an acrylic resin, if the acid value of the acrylic resin is too high, the dispersion stability of the metal particles in the coloring composition will decrease, and the gloss of the colored product produced using the coloring composition will be insufficient.

[0033] Furthermore, even if the coloring composition contains an acrylic resin with a predetermined acid value, if the metal particles are not surface-modified with a surface treatment agent, or if the metal particles are surface-modified with a surface modifier other than the compound shown in formula (1) or formula (2) above, the following problems will occur. Specifically, at least one of the following will be inferior: the dispersion stability of the metal particles in the coloring composition, the glossiness of the colored body produced using the coloring composition, and the adhesion between the treated object to which the coloring composition is applied and the colored part formed by the coloring composition. In particular, if a fluorine-based surface treatment agent is used instead of the compound shown in formula (1) or formula (2) above for the metal particles, the adhesion between the treated object to which the coloring composition is applied and the colored part formed by the coloring composition will be especially poor.

[0034] In the following explanation, the surface treatment agent, which is at least one selected from the group consisting of the compound represented by formula (1) and the compound represented by formula (2), is also referred to as the "specific surface treatment agent."

[0035] The components of the coloring composition of the present invention will be described below. [1-1] Metallic pigments The coloring composition of the present invention contains a metallic pigment consisting of multiple metal particles.

[0036] The metal particles that make up the metallic pigment are surface-modified with a specific surface treatment agent, which will be described in detail later. More specifically, it is believed that the OH groups on the surface of the metal particles react with the phosphorus-containing acid groups of the specific surface treatment agent, resulting in a covalent or hydrogen bond between the metal particles and the specific surface treatment agent.

[0037] Metal particles are those in which at least a portion of the visible part is made of metallic material, and typically, the area near the outer surface is made of metallic material.

[0038] Metal particles are components that significantly affect the appearance of colored materials manufactured using coloring compositions.

[0039] The metal particles only need to be composed of a metallic material in a region including the vicinity of the surface. For example, they may be entirely composed of a metallic material, or they may have a base made of a non-metallic material and a coating made of a metallic material covering the base. Furthermore, the metal particles may have an oxide film or the like, such as a passivation film, formed on their surface. Even with such metal particles, the problems described above have occurred in the past, and by applying the present invention, the excellent effects described above can be obtained.

[0040] The metal materials that make up the metal particles can be elemental metals or various alloys. Examples include aluminum, silver, gold, platinum, nickel, chromium, tin, zinc, indium, titanium, iron, and copper. Of these, it is preferable that the metal particles are composed of aluminum or aluminum alloys. The reason why aluminum and aluminum alloys are preferred is that they have a lower specific gravity compared to iron, etc. As a result, when particles composed of aluminum or aluminum alloys are dispersed in the coloring composition, sedimentation proceeds very slowly, which effectively prevents unevenness in concentration and allows the coloring composition to be stored for a longer period of time.

[0041] In addition, while suppressing an increase in the production cost of a colored body produced using a coloring composition, the gloss and high-class feeling of the colored body can be made particularly excellent. Aluminum and aluminum alloys inherently exhibit a particularly excellent gloss among various metal materials. However, when particles composed of these materials are applied to a coloring composition, the present inventors have found that the following problems occur. That is, the storage stability of the coloring composition becomes particularly low. In particular, when such a coloring composition is used as an inkjet ink composition, the present inventors have found that problems such as a decrease in ejection stability due to an increase in viscosity caused by gelation are particularly likely to occur. On the other hand, by using a metal pigment and a specific surface treatment agent in combination, even when particles composed of aluminum or an aluminum alloy are used, the occurrence of the above problems can be surely prevented. That is, since the metal particles are composed of aluminum or an aluminum alloy, the effects according to the present invention are more remarkably exhibited.

[0042] The metal particles may have any shape such as spherical, spindle-shaped, needle-shaped, etc., but are preferably in a flaky shape.

[0043] Thereby, on the object to be treated to which the coloring composition is applied, the main surface of the metal particles can be arranged along the surface shape of the object to be treated. As a result, the gloss and the like inherent in the metal material constituting the metal particles can be more effectively exhibited in the obtained colored body, and the gloss and high-class feeling of the colored body can be made particularly excellent, and the adhesion of the colored portion in the colored body can be made particularly excellent.

[0044] In the present invention, the flaky shape means a shape in which, when observed from a predetermined angle, for example, when viewed in a plan view, the area is larger than the area when observed from an angle orthogonal to the observation direction, such as a flat plate shape or a curved plate shape. In particular, when observed from the direction in which the projected area is maximum, that is, when viewed in a plan view, the area S1 [μm 2] and the area S0 [μm²] observed from the direction perpendicular to the observation direction that yields the largest observed area. 2 The ratio S1 / S0 to ] is preferably 2 or more, more preferably 5 or more, and even more preferably 8 or more. Furthermore, 10 or more is preferred, and 20 or more is even more preferred. The upper limit of S1 / S0 is not particularly limited, but it is preferably 1000, more preferably 500, and even more preferably 100. As for this value, for example, observations can be made on any 50 particles, and the average value calculated for these particles can be adopted. Observations can be made using, for example, an electron microscope, an atomic force microscope, etc.

[0045] Alternatively, the volume-average particle diameter (D50) and average thickness described later may be used, and after adjusting the units, the volume-average particle diameter (D50) / average thickness may be used as the above range.

[0046] When the metal particles are in the form of flakes, the lower limit of the average thickness of the metal particles is not particularly limited, but is preferably 5 nm, more preferably 10 nm, and even more preferably 15 nm. Also, when the metal particles are in the form of flakes, the upper limit of the average thickness of the metal particles is not particularly limited, but is preferably 90 nm, more preferably 70 nm, even more preferably 50 nm, and particularly preferably 30 nm. Furthermore, 25 nm or less is preferred.

[0047] The average thickness can be measured using an atomic force microscope. While not limited to this method, it can be measured using, for example, an atomic force microscope with NanoNavi E-Sweep (manufactured by SII Nanotechnology). For example, measurements can be taken on any 50 metal particles and the average value can be used.

[0048] This allows the effects of the flaky particle structure described above to be more pronounced.

[0049] The lower limit of the volume-average particle diameter of the metal particles is not particularly limited, but is preferably 0.20 μm, more preferably 0.25 μm, and even more preferably 0.30 μm. The upper limit of the volume-average particle diameter of the metal particles is not particularly limited, but is preferably 1.00 μm, more preferably 0.90 μm, and even more preferably 0.80 μm. Furthermore, 0.50 μm or less is preferred.

[0050] This improves the storage stability and water resistance of the coloring composition, while more effectively preventing unintended color unevenness in colored products manufactured using the coloring composition, and improving the gloss and adhesion of the colored portion of the colored product.

[0051] In this invention, the volume-average particle diameter refers to the median diameter of the volume distribution of a particle dispersion measured using the laser diffraction-scattering method. When multiple measurement results are expressed as the cumulative abundance ratio for each size, the volume-average particle diameter is the size of the particle that represents exactly 50% of the median value in the cumulative total. If the metal particles are flaky, the volume-average particle diameter shall be determined based on the shape and size of the metal particles when converted to a spherical form.

[0052] Furthermore, the upper limit of the particle size D90 at a volume cumulative distribution rate of 90% from the fine particle side of the metal particles contained in the coloring composition is preferably 1.50 μm, more preferably 1.20 μm, and even more preferably 0.95 μm.

[0053] This improves the storage stability and water resistance of the coloring composition, while more effectively preventing unintended color unevenness in colored products manufactured using the coloring composition, and improving the gloss and adhesion of the colored portion of the colored product.

[0054] The lower limit of the metal particle content in the coloring composition is not particularly limited, but is preferably 0.1% by mass, more preferably 0.2% by mass, and even more preferably 0.3% by mass. The upper limit of the metal particle content in the coloring composition is not particularly limited, but is preferably 30% by mass, more preferably 20% by mass, even more preferably 15% by mass, and particularly preferably 10% by mass. Furthermore, 5% by mass or less is preferred.

[0055] This makes it possible to improve the storage stability and water resistance of the coloring composition, while also achieving particularly excellent gloss and adhesion of the colored portion to the colored body formed using the coloring composition.

[0056] In particular, when the coloring composition is the ink itself ejected by an inkjet method, the lower limit of the metal particle content in the ink is not particularly limited, but is preferably 0.1% by mass, more preferably 0.2% by mass, and even more preferably 0.3% by mass. Also, when the coloring composition is the ink itself ejected by an inkjet method, the upper limit of the metal particle content in the ink is not particularly limited, but is preferably 2.4% by mass, more preferably 2.2% by mass, and even more preferably 1.8% by mass.

[0057] Furthermore, when the coloring composition is a stock solution used in the preparation of inks or paints, or is a paint, the lower limit of the metal particle content in the coloring composition is not particularly limited, but is preferably 2.0% by mass, more preferably 2.5% by mass, and even more preferably 3.0% by mass. Furthermore, when the coloring composition is a stock solution used in the preparation of inks ejected by an inkjet method, or is a paint, the upper limit of the metal particle content in the coloring composition is not particularly limited, but is preferably 30% by mass, more preferably 20% by mass, even more preferably 15% by mass, and most preferably 10% by mass.

[0058] The metal particles may be manufactured by any method, but if they are composed of Al, it is preferable that they are obtained by forming an Al film by vapor deposition and then crushing the film. This allows the inherent gloss and other properties of Al to be expressed more effectively in the colored portion formed using the coloring composition of the present invention. It also suppresses variations in properties between individual particles. Furthermore, this method allows for the suitable manufacture of even relatively thin metal particles.

[0059] When producing metal particles using such a method, for example, metal particles can be suitably produced by forming a film composed of Al on a substrate. As the substrate, for example, a plastic film such as polyethylene terephthalate can be used. The substrate may also have a release agent layer on the film-forming surface.

[0060] Furthermore, it is preferable that the pulverization is carried out by applying ultrasonic vibrations to the film in a liquid. This makes it possible to easily and reliably obtain metal particles of the particle size described later, and to suppress the occurrence of variations in size, shape, and properties among the metal particles.

[0061] Furthermore, when grinding is performed using the method described above, suitable liquids include alcohols, hydrocarbon compounds, ether compounds, and polar compounds such as propylene carbonate, γ-butyrolactone, N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, cyclohexanone, and acetonitrile. By using such liquids, it is possible to prevent unintended oxidation of metal particles, achieve particularly excellent productivity of metal particles, and minimize variations in size, shape, and properties between individual particles.

[0062] Examples of alcohols include methanol, ethanol, propanol, and butanol. Examples of hydrocarbon compounds include n-heptane, n-octane, decane, dodecane, tetradecane, toluene, xylene, cymene, durene, indene, dipentene, tetrahydronaphthalene, decahydronaphthalene, and cyclohexylbenzene. Examples of ether compounds include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, tetraethylene glycol monobutyl ether, diethylene glycol methyl ethyl ether, diethylene glycol monobutyl ether acetate, diethylene glycol n-butyl ether, tripropylene glycol dimethyl ether, triethylene glycol diethyl ether, 1,2-dimethoxyethane, bis(2-methoxyethyl) ether, p-dioxane, and tetrahydrofuran.

[0063] [1-2] Acrylic resin The coloring composition of the present invention contains an acrylic resin with an acid value of 200 mgKOH / g or less.

[0064] The acrylic resin primarily has the function of improving the adhesion between the workpiece to which the coloring composition is applied and the colored portion formed by the coloring composition in colored bodies manufactured using the coloring composition, as well as improving the dispersion stability of metal particles in the coloring composition and the glossiness of the colored body manufactured using the coloring composition.

[0065] The acrylic resin may be a polymer mainly composed of acrylic monomers, but the proportion of acrylic monomers in the total constituent monomers constituting the acrylic resin is preferably 50% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more. The upper limit is 100% by mass or less. The proportion of constituent monomers in the resin is the mass percentage of the monomer composition used when the resin was polymerized and prepared.

[0066] This makes it possible to improve the dispersion stability of metal particles in the coloring composition, the adhesion of the colored portion in the colored body produced using the coloring composition, and the glossiness of the colored body.

[0067] Examples of acrylic monomers that make up acrylic resins include (meth)acrylic acid and their ester compounds.

[0068] More specifically, examples of acrylic monomers include (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate.

[0069] Acrylic resins may contain monomers other than the acrylic monomers mentioned above as constituent monomers. Examples of such monomers include vinyl monomers. Examples of vinyl monomers include styrene.

[0070] However, the proportion of monomers other than acrylic monomers in the total constituent monomers constituting the acrylic resin is preferably 50% by mass or less, more preferably 20% by mass or less, and even more preferably 10% by mass or less. The lower limit is 0% by mass or more. For example, the proportion of vinyl monomers may be within the above range.

[0071] The acid value of the acrylic resin should be 200 mgKOH / g or less. The lower limit is 0 mgKOH / g or more. Preferably it is 1 mgKOH / g to 100 mgKOH / g, more preferably 2 mgKOH / g to 80 mgKOH / g, more preferably 3 mgKOH / g to 40 mgKOH / g, even more preferably 4 mgKOH / g to 30 mgKOH / g, and particularly preferably 5 mgKOH / g to 15 mgKOH / g. Furthermore, 5 mgKOH / g to 10 mgKOH / g is preferred.

[0072] This makes it possible to improve the dispersion stability of metal particles in the coloring composition, the adhesion of the colored portion in the colored body produced using the coloring composition, and the glossiness of the colored body.

[0073] The acid value can be measured by potentiometric titration. For example, the "AT610" manufactured by Kyoto Electronics Manufacturing Co., Ltd. can be used as the titrator. For example, the measurement can be performed according to JIS K0070.

[0074] The acid value can be adjusted, for example, by increasing or decreasing the proportion of monomers having an acid value in the monomer composition that makes up the acrylic resin. The acid value can be increased by increasing the proportion of monomers having an acid value, or decreased by decreasing the proportion of monomers having an acid value. Examples of monomers having an acid value include monomers with acidic groups. Examples of acidic groups include carboxyl groups and sulfo groups. Examples of monomers with acidic groups include (meth)acrylic acid.

[0075] The lower limit of the weight-average molecular weight of the acrylic resin is not particularly limited, but is preferably 5000, more preferably 6000, and even more preferably 7000. The upper limit of the weight-average molecular weight of the acrylic resin is also not particularly limited, but is preferably 20000, more preferably 19000, and even more preferably 18000. The weight-average molecular weight can be measured by gel permeation chromatography.

[0076] This makes it possible to improve the dispersion stability of metal particles in the coloring composition, the adhesion of the colored portion in the colored body produced using the coloring composition, and the glossiness of the colored body.

[0077] The lower limit of the acrylic resin content in the coloring composition is not particularly limited, but is preferably 0.01% by mass, more preferably 0.03% by mass, and even more preferably 0.07% by mass. The upper limit of the acrylic resin content in the coloring composition is not particularly limited, but is preferably 15% by mass, more preferably 10% by mass, and even more preferably 7.0% by mass.

[0078] This makes it possible to improve the dispersion stability of metal particles in the coloring composition, the adhesion of the colored portion in the colored body produced using the coloring composition, and the glossiness of the colored body.

[0079] In particular, when the coloring composition is the ink itself ejected by the inkjet method, the lower limit of the acrylic resin content in the ink is not particularly limited, but is preferably 0.01% by mass, more preferably 0.03% by mass, and even more preferably 0.07% by mass. Also, when the coloring composition is the ink itself ejected by the inkjet method, the upper limit of the acrylic resin content in the ink is not particularly limited, but is preferably 5.0% by mass, more preferably 2.0% by mass, and even more preferably 0.7% by mass.

[0080] Furthermore, when the coloring composition is a stock solution used in the preparation of inks or paints, or is a paint, the lower limit of the acrylic resin content in the coloring composition is not particularly limited, but is preferably 0.1% by mass, more preferably 0.3% by mass, and even more preferably 0.7% by mass. Furthermore, when the coloring composition is a stock solution used in the preparation of inks ejected by an inkjet method, or is a paint, the upper limit of the acrylic resin content in the coloring composition is not particularly limited, but is preferably 15% by mass, more preferably 10% by mass, and even more preferably 7.0% by mass.

[0081] The content of acrylic resin in the coloring composition is preferably 1.0 part by mass or more and 50 parts by mass or less, more preferably 1.5 parts by mass or more and 40 parts by mass or less, and even more preferably 2.0 parts by mass or more and 30 parts by mass or less, per 100 parts by mass of metal particles.

[0082] This makes it possible to improve the dispersion stability of metal particles in the coloring composition, the adhesion of the colored portion in the colored body produced using the coloring composition, and the glossiness of the colored body.

[0083] [1-3] Specific surface treatment agents The aforementioned metal particles are surface-modified with a specific surface treatment agent.

[0084] The specific surface treatment agent is at least one selected from the group consisting of the compound represented by formula (1) and the compound represented by formula (2).

[0085] In formulas (1) and (2) above, R may be any hydrocarbon group having 1 or more carbon atoms, but it is preferably a hydrocarbon group having 5 to 30 carbon atoms, more preferably a hydrocarbon group having 10 to 30 carbon atoms, even more preferably a hydrocarbon group having 12 to 26 carbon atoms, and even more preferably a hydrocarbon group having 12 to 25 carbon atoms. Furthermore, it is preferably a hydrocarbon group having 13 to 24 carbon atoms, and even more preferably a hydrocarbon group having 14 to 22 carbon atoms.

[0086] This makes it possible to improve the dispersion stability of metal particles in the coloring composition, and to improve the gloss of the colored body produced using the coloring composition, as well as the adhesion between the workpiece to which the coloring composition is applied and the colored part formed by the coloring composition.

[0087] Examples of the hydrocarbon group include alkyl groups, alkenyl groups, and alkynyl groups.

[0088] The coloring composition of the present invention may contain multiple types of compounds as specific surface treatment agents. In such cases, the same metal particles may be surface-treated with multiple types of surface treatment agents. Furthermore, the coloring composition of the present invention may contain metal particles that have been surface-treated with different specific surface treatment agents.

[0089] Surface treatment of metal particles with a specific surface treatment agent may be carried out, for example, by including the specific surface treatment agent in the liquid when forming metal particles by crushing a metal film formed by a vapor phase deposition method in a liquid, as described above.

[0090] When surface treatment is applied to the same metal particles using multiple types of specific surface treatment agents, the surface treatment may be performed in multiple steps corresponding to each specific surface treatment agent, or the surface treatment may be performed using multiple types of specific surface treatment agents in a single step.

[0091] The lower limit of the content of the specific surface treatment agent in the coloring composition is not particularly limited, but is preferably 0.01% by mass, more preferably 0.03% by mass, and even more preferably 0.05% by mass. The upper limit of the content of the specific surface treatment agent in the coloring composition is not particularly limited, but is preferably 10% by mass, more preferably 7.0% by mass, and even more preferably 5.0% by mass.

[0092] This makes it possible to further improve the dispersion stability of metal particles in the coloring composition, the glossiness of the colored body produced using the coloring composition, and the adhesion of the colored portion to the colored body.

[0093] In particular, when the coloring composition is the ink itself ejected by the inkjet method, the lower limit of the content of the specific surface treatment agent in the ink is not particularly limited, but is preferably 0.01% by mass, more preferably 0.03% by mass, and even more preferably 0.05% by mass. Also, when the coloring composition is the ink itself ejected by the inkjet method, the upper limit of the content of the specific surface treatment agent in the ink is not particularly limited, but is preferably 1.5% by mass, more preferably 1.0% by mass, and even more preferably 0.8% by mass.

[0094] Furthermore, when the coloring composition is a stock solution used in the preparation of inks or paints, or is a paint, the lower limit of the content of the specific surface treatment agent in the coloring composition is not particularly limited, but is preferably 0.50% by mass, more preferably 0.70% by mass, and even more preferably 1.0% by mass. Furthermore, when the coloring composition is a stock solution used in the preparation of inks ejected by an inkjet method, or is a paint, the upper limit of the content of the specific surface treatment agent in the coloring composition is not particularly limited, but is preferably 10% by mass, more preferably 7.0% by mass, and even more preferably 5.0% by mass.

[0095] The content of the specific surface treatment agent in the coloring composition is not particularly limited, but is preferably 1.0 part by mass or more and 50 parts by mass or less, more preferably 1.5 parts by mass or more and 40 parts by mass or less, and even more preferably 2.0 parts by mass or more and 30 parts by mass or less, per 100 parts by mass of metal particles.

[0096] This makes it possible to further improve the dispersion stability of metal particles in the coloring composition, the glossiness of the colored object produced using the coloring composition, and the adhesion of the colored portion on the colored object. Furthermore, when the coloring composition is an inkjet ink composition, it is possible to further improve the ejection stability of the inkjet ink composition, especially when stored for a long period of time or under harsh conditions.

[0097] [1-4]Liquid medium components The coloring composition of the present invention contains a liquid medium component.

[0098] The liquid medium component is a component that is liquid on its own, and in the coloring composition of the present invention, it mainly functions as a dispersion medium for dispersing metal particles. It also has the function of making it easier for the coloring composition to adhere to the object to be colored.

[0099] Furthermore, if the coloring composition contains a liquid medium component, and the coloring composition is the ink itself that is ejected by the inkjet method, then it becomes possible to eject the ink by inkjet. Examples of liquid media components include water and various organic solvents.

[0100] When the coloring composition of the present invention is a solvent-based composition containing an organic solvent as a liquid medium component, the dispersion stability of metal particles in the coloring composition, the glossiness of the colored body produced using the coloring composition, and the adhesion of the colored portion on the colored body can be further improved.

[0101] Suitable organic solvents to be included in the coloring composition of the present invention include, for example, alcohols, hydrocarbon compounds, ether compounds, ketones, esters, and polar compounds such as propylene carbonate, N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, cyclohexanone, and acetonitrile.

[0102] Examples of alcohols include monohydric alcohols such as methanol, ethanol, propanol, isopropanol, and butanol; and polyhydric alcohols such as ethylene glycol, propylene glycol, and 1,2-hexanediol. Examples of hydrocarbon compounds include n-heptane, n-octane, decane, dodecane, tetradecane, toluene, xylene, cymene, durene, indene, dipentene, tetrahydronaphthalene, decahydronaphthalene, and cyclohexylbenzene. Examples of ether compounds include glycol ethers, which are preferred. Examples of glycol ethers include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, tetraethylene glycol monobutyl ether, diethylene glycol methyl ethyl ether, diethylene glycol monobutyl ether acetate, diethylene glycol n-butyl ether, tripropylene glycol dimethyl ether, triethylene glycol diethyl ether, 1,2-dimethoxyethane, and bis(2-methoxyethyl) ether. Other ether compounds include p-dioxane and tetrahydrofuran. Ketones include, for example, acetone, methyl ethyl ketone, and diethyl ketone. Esters include, for example, ethyl acetate, propyl acetate, and butyl acetate. Cyclic esters are also included as esters. Examples of cyclic esters include lactones such as γ-butyrolactone, which are preferred.

[0103] As the coloring composition of the present invention, a solvent-based composition containing an organic solvent as the main liquid medium component is preferred.

[0104] When the coloring composition is a solvent-based composition, the organic solvent preferably contains one or more selected from the group consisting of ethers, esters, ketones, and alcohols. In particular, it is preferable to contain one or more selected from the group consisting of ethers and esters. Glycol ethers and cyclic esters are particularly preferred, and glycol ethers are more preferred.

[0105] In particular, it is more preferable to include one or more selected from the group consisting of diethylene glycol diethyl ether, tetraethylene glycol monobutyl ether, and γ-butyrolactone.

[0106] This improves the dispersion stability of metal particles in the coloring composition, the glossiness of colored objects produced using the coloring composition, and the adhesion of colored parts to the colored objects. Furthermore, it improves the moisture retention of the coloring composition, for example, in the case of an inkjet ink composition, it more effectively prevents the unintended precipitation of solid components due to drying in the inkjet head, etc. Additionally, it allows for more favorable adjustment of the viscosity of the coloring composition.

[0107] In particular, when the coloring composition of the present invention is a solvent-based composition, the proportion of the organic solvent in the total liquid media components constituting the coloring composition of the present invention is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more. The upper limit is 100% by mass or less. This makes the aforementioned effects even more pronounced.

[0108] When the coloring composition of the present invention is a solvent-based composition, the water content in the total liquid media components is preferably less than 30% by mass. Furthermore, the water content in the total liquid media components constituting the coloring composition of the present invention is preferably sufficiently low, more specifically, 5.0% by mass or less, more preferably 1.0% by mass or less, and even more preferably 0.1% by mass or less.

[0109] The coloring composition of the present invention may be an aqueous composition containing water as the main liquid medium component.

[0110] When the coloring composition of the present invention is an aqueous composition, the proportion of water in the total liquid media components constituting the coloring composition of the present invention is preferably 30% by mass or more, more preferably 40% by mass or more, and even more preferably 55% by mass or more. When the coloring composition of the present invention is an aqueous composition, the upper limit of the proportion of water in the total liquid media components constituting the coloring composition of the present invention is 100% by mass.

[0111] When the coloring composition of the present invention is an aqueous composition containing water as a liquid medium component, it may also contain an organic solvent along with water as a liquid medium component. The content of the organic solvent in the liquid medium component of the aqueous composition is preferably less than 50% by mass, more preferably 40% by mass or less, and even more preferably 30% by mass or less. The lower limit is 0% by mass or more.

[0112] When the coloring composition of the present invention is an aqueous composition, the organic solvent included with water is preferably a liquid component that is soluble in water, i.e., a water-soluble organic solvent.

[0113] This improves the dispersion stability of metal particles in the coloring composition, the glossiness of colored objects produced using the coloring composition, and the adhesion of the colored portion to the colored object. Furthermore, it improves the moisture retention of the coloring composition, for example, in the case of an inkjet ink composition, it more effectively prevents the unintended precipitation of solid components due to drying in the inkjet head, etc. Additionally, it allows for more favorable adjustment of the viscosity of the coloring composition.

[0114] The water-soluble organic solvent can be any liquid component that is water-soluble, but for example, a liquid component with a solubility in water of 2 g / 100 g water or more at 25°C is preferably used.

[0115] The boiling point of a water-soluble organic solvent at 1 atmosphere is preferably between 110°C and 300°C.

[0116] This further improves the moisture retention of the coloring composition. For example, when the coloring composition is an inkjet ink composition, it can more effectively prevent the unintended precipitation of solid components of the coloring composition due to drying in the inkjet head, etc. As a result, the ejection stability of the coloring composition produced by the inkjet method can be further improved. In addition, after the coloring composition is ejected, it can be relatively easily evaporated when necessary, more effectively preventing the unintended residue of liquid media components in the colored body produced using the coloring composition.

[0117] When the coloring composition of the present invention is an aqueous composition, examples of water-soluble organic solvents included with water include alkyl monoalcohols, glycerin, glycols, glycol monoethers, lactams, monohydric alcohols, etc., and one or more selected from these can be used in combination.

[0118] Examples of glycols include triethanolamine, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, and 1,2-hexanediol. Examples of glycol monoethers include triethylene glycol monobutyl ether. Examples of lactams include 2-pyrrolidone. Examples of monohydric alcohols include ethanol, methanol, propanol, isopropanol, butanol, and phenoxyethanol.

[0119] The lower limit of the liquid medium component content in the coloring composition of the present invention is not particularly limited, but is preferably 60.0% by mass, more preferably 70.0% by mass, and even more preferably 75.0% by mass. The upper limit of the liquid medium component content in the coloring composition of the present invention is not particularly limited, but is preferably 99.7% by mass, more preferably 99.5% by mass, and even more preferably 99.0% by mass. This makes it possible to make the viscosity of the coloring composition more suitable.

[0120] [1-5] Polyoxyalkyleneamine compounds The coloring composition of the present invention may contain a polyoxyalkyleneamine compound, which is an amine compound having a polyoxyalkylene structure within its molecule.

[0121] This improves the dispersion stability of metal particles in the coloring composition, the adhesion of the colored portion in the colored body produced using the coloring composition, and the glossiness of the colored body. It also improves the abrasion resistance of the colored body produced using the coloring composition. Furthermore, when the coloring composition is used as an inkjet ink composition, it improves the ejection stability of the inkjet ink composition.

[0122] The polyoxyalkyleneamine compound may be any amine compound having a polyoxyalkylene structure within its molecule, but it is preferably a compound represented by the following formula (3) or a salt thereof.

[0123] R 1 -(OR 2 ) x -NH2(3) (In the formula, R 1 R is a hydrogen atom or an alkyl group having 4 or fewer carbon atoms. 2 R is an alkylene group having 5 or fewer carbon atoms, X is an integer of 5 or more, and polyoxyalkyleneamine compounds have R in their molecule. 2It may contain multiple types of alkylene groups with different conditions.

[0124] This improves the dispersion stability of metal particles in the coloring composition, the glossiness of the colored object produced using the coloring composition, and the adhesion of the colored portion on the colored object. Furthermore, when the coloring composition is an inkjet ink composition, it improves the ejection stability of the inkjet ink composition, especially when stored for a long period of time or under harsh conditions.

[0125] As described above, the polyoxyalkyleneamine compound is preferably the compound represented by formula (3) or a salt thereof.

[0126] In formula (3), R 1 The alkyl group is preferably one with 4 or fewer carbon atoms, and more preferably one or two carbon atoms. 2 It is preferably an alkylene group having 1 to 3 carbon atoms, and may be a linear alkylene group or a branched alkylene group.

[0127] The polyoxyalkyleneamine compound is, among the compounds represented by formula (3) above or salts thereof, particularly preferably the compound represented by formula (4) below or a salt thereof.

[0128] R 1 -(OCH2CH2) m -(OCH2CH(CH3)) n -NH2(4) (In the formula, R 1 n is a hydrogen atom or an alkyl group having 4 or fewer carbon atoms, n and m are each independently 0 or an integer of 1 or greater, and m+n is an integer of 10 or greater. The order of the oxyethylene unit and oxypropylene unit within the polyoxyalkyleneamine compound molecule is irrelevant. This makes the aforementioned effects even more pronounced.

[0129] Furthermore, the lower limit of the m / n value, which is the ratio of m to n in formula (4) above, that is, the ratio of the amount of oxyethylene units to the amount of oxypropylene units within the polyoxyalkyleneamine compound molecule, is preferably 0.05, more preferably 0.15, and even more preferably 0.70. The upper limit of the m / n value is preferably 10.0, more preferably 9.5, and even more preferably 9.0.

[0130] This makes it possible to further improve the dispersion stability of metal particles in the coloring composition, the glossiness of the colored object produced using the coloring composition, and the adhesion of the colored portion on the colored object. Furthermore, when the coloring composition is an inkjet ink composition, it is possible to further improve the ejection stability of the inkjet ink composition, especially when stored for a long period of time or under harsh conditions.

[0131] As described above, the order of the oxyethylene unit and the oxypropylene unit in formula (4) does not matter. More specifically, in formula (4), an amino group is bonded to the end of a series of oxyethylene units and a methyl group is bonded to the end of a series of oxypropylene units, but it is also possible for an amino group to be bonded to the end of a series of oxypropylene units and a methyl group to be bonded to the end of a series of oxyethylene units. Furthermore, the compound represented by formula (4) may be a block copolymer or a random copolymer.

[0132] The lower limit of the weight-average molecular weight of the polyoxyalkyleneamine compound is not particularly limited, but is preferably 400, more preferably 500, even more preferably 600, and most preferably 1000. The upper limit of the weight-average molecular weight of the polyoxyalkyleneamine compound is not particularly limited, but is preferably 8000, more preferably 5000, and even more preferably 3000.

[0133] This makes it possible to further improve the dispersion stability of metal particles in the coloring composition, the glossiness of the colored object produced using the coloring composition, and the adhesion of the colored portion on the colored object. Furthermore, when the coloring composition is an inkjet ink composition, it is possible to further improve the ejection stability of the inkjet ink composition, especially when stored for a long period of time or under harsh conditions.

[0134] The coloring composition of the present invention may contain multiple types of compounds as polyoxyalkyleneamine compounds.

[0135] The lower limit of the polyoxyalkyleneamine compound content in the coloring composition is not particularly limited, but is preferably 0.005% by mass, more preferably 0.007% by mass. Furthermore, it is preferably 0.01% by mass, more preferably 0.02% by mass, and even more preferably 0.03% by mass. The upper limit of the polyoxyalkyleneamine compound content in the coloring composition is not particularly limited, but is preferably 5.0% by mass, particularly preferably 3.0% by mass, more preferably 2.0% by mass, and even more preferably 1.5% by mass. It is also preferable to set the upper and lower limits to the ranges described later.

[0136] This makes it possible to further improve the dispersion stability of metal particles in the coloring composition, the glossiness of the colored object produced using the coloring composition, and the adhesion of the colored portion on the colored object. Furthermore, when the coloring composition is an inkjet ink composition, it is possible to further improve the ejection stability of the inkjet ink composition, especially when stored for a long period of time or under harsh conditions.

[0137] In particular, when the coloring composition is the ink itself ejected by an inkjet method, the lower limit of the content of the polyoxyalkyleneamine compound in the ink is not particularly limited, but is preferably 0.005% by mass, more preferably 0.007% by mass. Furthermore, it is preferably 0.01% by mass, more preferably 0.02% by mass, and even more preferably 0.03% by mass. Also, when the coloring composition is the ink itself ejected by an inkjet method, the upper limit of the content of the polyoxyalkyleneamine compound in the ink is not particularly limited, but is preferably 1.0% by mass, more preferably 0.70% by mass, and even more preferably 0.50% by mass. Furthermore, 0.40% by mass is particularly preferred.

[0138] Furthermore, when the coloring composition is a stock solution used in the preparation of inks or paints, or is a paint, the lower limit of the content of the polyoxyalkyleneamine compound in the coloring composition is not particularly limited, but is preferably 0.025% by mass, more preferably 0.035% by mass. Even more preferably 0.05% by mass, more preferably 0.10% by mass, and still more preferably 0.20% by mass. Furthermore, when the coloring composition is a stock solution used in the preparation of inks ejected by an inkjet method, or is a paint, the upper limit of the content of the polyoxyalkyleneamine compound in the coloring composition is not particularly limited, but is preferably 5.0% by mass, more preferably 3.5% by mass. Even more preferably 3.0% by mass, more preferably 2.0% by mass, and still more preferably 1.5% by mass.

[0139] The lower limit of the polyoxyalkyleneamine compound content in the coloring composition is preferably 0.5 parts by mass, more preferably 0.7 parts by mass, per 100 parts by mass of metal particles. Furthermore, it is preferably 1.0 part by mass, more preferably 1.5 parts by mass, and even more preferably 2.0 parts by mass. The upper limit of the polyoxyalkyleneamine compound content in the coloring composition is preferably 100 parts by mass, more preferably 70 parts by mass, per 100 parts by mass of metal particles. Furthermore, it is preferably 50 parts by mass, even more preferably 40 parts by mass, even more preferably 30 parts by mass, and even more preferably 20 parts by mass.

[0140] This makes it possible to further improve the dispersion stability of metal particles in the coloring composition, the glossiness of the colored object produced using the coloring composition, and the adhesion of the colored portion on the colored object. Furthermore, when the coloring composition is an inkjet ink composition, it is possible to further improve the ejection stability of the inkjet ink composition, especially when stored for a long period of time or under harsh conditions.

[0141] When the content of the polyoxyalkyleneamine compound in the coloring composition is XA [mass%] and the content of the specific surface treatment agent in the coloring composition is XP [mass%], the lower limit of the XA / XP value is preferably 0.02, more preferably 0.05, and even more preferably 0.07. The upper limit of the XA / XP value is preferably 10.0, more preferably 7.0, and even more preferably 5.0. Furthermore, it is preferably 3.0, more preferably 2.0, and even more preferably 1.5.

[0142] This makes it possible to improve the dispersion stability of metal particles in the coloring composition, the glossiness of the colored body produced using the coloring composition, and the adhesion and abrasion resistance of the colored portion on the colored body.

[0143] [1-6] Other ingredients The coloring composition of the present invention may contain components other than those described above. Hereinafter, these components will also be referred to as other components. Examples of such components include surface treatment agents other than specific surface treatment agents, resins other than acrylic resins, leveling agents, polymerization accelerators, polymerization inhibitors, photopolymerization initiators, dispersants, surfactants, penetration accelerators, humectants, colorants, fixing agents, fungicides, preservatives, antioxidants, chelating agents, thickeners, sensitizers, and the like.

[0144] Examples of resins other than acrylic resins include ester resins, urethane resins, and cellulose resins.

[0145] Preferred surfactants include silicone-based surfactants and acetylene glycol-based surfactants.

[0146] However, the content of other components in the coloring composition of the present invention is preferably 2.0% by mass or less, more preferably 1.0% by mass or less, and even more preferably 0.1% by mass or less.

[0147] [1-7] Others The coloring composition of the present invention may, for example, be used directly to form the colored portion. In other words, the coloring composition is a composition that is attached to a workpiece to color the workpiece (the object to be colored). That is, it is a composition used in the attachment step in the coloring method described later.

[0148] In this case, the coloring composition may include, for example, ink or paint. The ink is not particularly limited, but examples include inkjet ink.

[0149] Alternatively, the coloring composition may be a composition used to prepare a composition that is applied to the object to be treated to color it. In this case, the coloring composition is not used in the application step in the coloring method described later, but rather is a composition used to prepare the coloring composition used in the application step. That is, the coloring composition is mixed with other components, the concentration is adjusted, etc., to prepare a composition to be used in the coloring method, and the resulting composition is used to form the colored portion. In this case, examples of the coloring composition include pigment dispersions and stock solutions used to prepare a composition that is applied to the object to be treated to color it.

[0150] In particular, the coloring composition is preferably an inkjet ink composition. Conventionally, when attempting to apply a coloring composition to an inkjet method, problems arose such as reduced ejection stability by the inkjet method, decreased glossiness of the produced colored material, and reduced adhesion of the colored portion to the colored material. However, according to the present invention, the occurrence of such problems can be effectively prevented. In other words, the effects of the present invention are more pronounced when the coloring composition is an inkjet ink composition.

[0151] Inkjet ink is ink that is ejected from an inkjet head using the inkjet method and used for recording.

[0152] The object to be treated is an object to which a coloring composition is applied and colored; in other words, the object to be colored. When the coloring composition is ink, the object to be treated is usually a recording medium.

[0153] The objects to be processed are not particularly limited, but examples include, in addition to recording media, boards, walls, floors, fences, automobiles, and other articles.

[0154] The recording medium can be either absorbent or non-absorbent. For example, it can be made of paper such as plain paper or inkjet paper, plastic materials, metals, ceramics, wood, seashells, cotton, polyester, wool or other natural or synthetic fibers, or nonwoven fabrics, but it is preferable that it be uncolored. The shape of the recording medium is not particularly limited and can be any shape, such as a sheet.

[0155] Examples of recording media made from plastic materials include plastic films and plastic sheets. Examples of plastics, though not limited to them, include polyvinyl chloride, polyester, and polyolefin. Examples of polyester include polyethylene terephthalate.

[0156] The upper limit of the viscosity of the coloring composition of the present invention at 25°C, as measured using a rotational viscometer in accordance with JIS Z8809, is not particularly limited, but is preferably 25 mPa·s, and more preferably 15 mPa·s. The lower limit of the viscosity of the coloring composition of the present invention at 25°C, as measured using a rotational viscometer in accordance with JIS Z8809, is not particularly limited, but is preferably 1.5 mPa·s.

[0157] This allows for, for example, the ink ejection of a coloring composition by an inkjet method to be performed more favorably.

[0158] [2] Coloring method Next, I will explain the coloring method.

[0159] The coloring method using the coloring composition of the present invention comprises a step of adhering the composition to the object to be colored (adhesion step).

[0160] This makes it possible to provide a coloring method that can be applied to the manufacture of colored materials with excellent gloss and adhesion of the colored portion.

[0161] The step of applying the coloring composition of the present invention to a workpiece can be carried out, for example, by various printing methods such as inkjet printing, or by various coating methods using a bar coater, spray, roll coater, brush, etc. If the coloring composition is an ink, the coloring method is also a recording method.

[0162] In particular, a coloring method using the coloring composition of the present invention preferably includes a step of ejecting the aforementioned coloring composition of the present invention by an inkjet method and adhering it to a recording medium.

[0163] This makes it possible to provide a coloring method that can be applied to the production of colored materials with excellent gloss and adhesion of the colored portion, while enjoying the benefits of applying inkjet methods, such as being able to more favorably form fine patterns and having excellent on-demand capabilities.

[0164] When dispensing a coloring composition by inkjet, various inkjet methods can be used, such as a piezo method or a method that uses bubbles generated by heating the ink to dispense it. However, from the viewpoint of preventing deterioration of the coloring composition, the piezo method is preferred.

[0165] The coloring composition can be ejected by the inkjet method using a known droplet ejection device.

[0166] The colored portion formed by the coloring composition may, for example, have a predetermined pattern, or it may be formed over the entire surface of the object to be treated.

[0167] [3] Colored body Next, the colored material according to the present invention will be described.

[0168] The colored material according to the present invention is manufactured by applying the coloring composition described above to a material to be treated, which is the material to be colored.

[0169] Such colored bodies have excellent gloss, superior adhesion of the colored portion formed using the coloring composition, and a colored portion in which defects are prevented.

[0170] The colored material according to the present invention may be used for any purpose, for example, on recording materials, decorative items, or other applications. Specific examples of the colored material according to the present invention include vehicle interior parts such as console lids, switch bases, center clusters, interior panels, emblems, center consoles, and meter nameplates, as well as operating parts for various electronic devices, decorative parts that provide a decorative effect, indicators, logos, and other displays.

[0171] Although the present invention has been described above based on preferred embodiments, the present invention is not limited thereto. [Examples]

[0172] Next, specific embodiments of the present invention will be described. [4] Synthesis of acrylic resins First, prior to the production of the coloring composition, an acrylic resin was synthesized.

[0173] (Synthesis Example 1) After purging a reaction vessel equipped with a stirring motor, impeller, temperature sensor, and reflux condenser with nitrogen, 500 parts by mass of methyl ethyl ketone were charged, and the internal temperature was raised to 77°C while stirring.

[0174] To this, 60 parts by mass of butyl methacrylate, 315 parts by mass of 2-ethylhexyl methacrylate, 125 parts by mass of ethyl acrylate, and 8 parts by mass of di-t-butyl peroxide were added dropwise over 4 hours. After the addition was complete, the mixture was kept warm at an internal temperature of 77°C for 1 hour, and the reflux condenser was replaced with a distillation tube. The remaining monomers and solvents in the system were removed under atmospheric pressure and, if appropriate, reduced pressure until the internal temperature reached 100°C. After that, the mixture was cooled to room temperature to obtain acrylic resin A. Acrylic resin A had a weight-average molecular weight of 17,000 and an acid value of 0 mgKOH / g. The acid value was measured by the method described above.

[0175] (Synthesis Example 2) Acrylic resin B, an acrylic resin, was synthesized in the same manner as in Synthesis Example 1, except that methacrylic acid was used as the monomer and the amounts of each monomer used were as shown in Table 1. The acid value was 10 mg KOH / g.

[0176] (Synthesis Examples 3-6) Taking advantage of the fact that the acid value increases with the amount of methacrylic acid used, the amount of methacrylic acid used was gradually increased compared to Synthesis Example 2. The monomer composition was adjusted by reducing the other monomers in a uniform ratio compared to Synthesis Example 2, proportionally to the increase in methacrylic acid. The acid value was measured, and the monomer composition was finely adjusted to achieve the desired acid value. The mixture was then polymerized again to further fine-tune the acid value. In this way, acrylic resins C to F were synthesized. Acrylic resin C had an acid value of 50 mgKOH / g. Acrylic resin D had an acid value of 80 mgKOH / g. Acrylic resin E had an acid value of 150 mgKOH / g. Acrylic resin F had an acid value of 300 mgKOH / g. The weight-average molecular weight of all was approximately 17,000.

[0177] The conditions for the acrylic resins obtained in each of the above synthesis examples are summarized in Table 1. In Table 1, butyl methacrylate is denoted as "BMA", 2-ethylhexyl methacrylate as "2-EHMA", ethyl acrylate as "EA", and methacrylic acid as "MA".

[0178] [Table 1]

[0179] [5] Manufacture of coloring compositions (Example 1) First, we prepared a polyethylene terephthalate film with a smooth surface and a surface roughness Ra of 0.02 μm or less.

[0180] Next, a release layer was formed on the entire surface of one side of the film by coating it with a release resin solubilized with acetone using a roll coater.

[0181] A polyethylene terephthalate film with a release layer formed on it was transported into a vacuum deposition apparatus at a speed of 5 m / s, and a 12 nm thick film composed of Al was formed under reduced pressure.

[0182] Next, a polyethylene terephthalate film with an Al membrane formed on it was immersed in tetrahydrofuran, and ultrasonic vibrations at 40 kHz were applied to obtain a dispersion of metal powder, which is an aggregate of Al metal particles.

[0183] Next, tetrahydrofuran was removed using a centrifuge, and diethylene glycol diethyl ether was added to obtain a suspension containing 5% by mass of metal powder.

[0184] Next, this suspension was processed using a circulating high-power ultrasonic grinder to grind the metal particles to a predetermined size. This process involved applying 20 kHz ultrasound.

[0185] Next, the polyoxyalkyleneamine compound represented by formula (4) above was added to the suspension in a mass ratio to the metal particles that matched the values ​​in Table 2. The suspension was then subjected to heat treatment at 55°C for 1 hour under 40 kHz ultrasonic irradiation to disperse the aggregated metal particles into primary particles. Here, the polyoxyalkyleneamine compound used was a block copolymer in which an amino group is bonded to the end of a continuous oxyethylene unit and a methyl group is bonded to the end of a continuous oxypropylene unit, satisfying the condition that m / n between m and n in formula (4) is 3.1, and having a weight-average molecular weight of 2000.

[0186] Furthermore, a specific surface treatment agent, which is the compound shown in formula (1) above, was added in a proportion such that its mass ratio to the metal particles was the value shown in Table 2. In this example, the specific surface treatment agent used was a mixture of a compound in which R in formula (1) is an n-decyl group and a compound in which a is 1, and a compound in which a is 2.

[0187] Then, by heat treatment at 55°C for 3 hours under 28kHz ultrasonic irradiation, a specific surface treatment agent was reacted on the surface of the metal particles, and a dispersion of metal particles surface-modified with the specific surface treatment agent was obtained.

[0188] Subsequently, diethylene glycol diethyl ether, tetraethylene glycol monobutyl ether, and γ-butyrolactone were added to the resulting dispersion of metal particles, and then acrylic resin A was added to obtain a coloring composition with the composition shown in Table 2.

[0189] The volume-average particle size of the metal particles contained in the coloring composition obtained in this way was 0.25 μm, and the average thickness was 12 nm.

[0190] (Examples 2-21) A coloring composition was manufactured in the same manner as in Example 1, except that the metal pigment was configured as shown in Tables 2 and 3, and the types and ratios of the raw materials contained were changed to obtain the compositions shown in Tables 2 and 3. The average thickness of the metal particles was adjusted during Al deposition. The average particle size of the metal particles was adjusted by adjusting the amount of grinding during ultrasonic grinding.

[0191] (Comparative Examples 1-8) A coloring composition was prepared in the same manner as in Example 1, except that the type and ratio of raw materials used in the preparation of the coloring composition were changed to obtain the composition shown in Table 3.

[0192] Tables 2 and 3 summarize the composition of the metal pigments contained in the coloring compositions for each of the above examples and comparative examples, as well as the composition of the coloring compositions themselves. The components in the tables are as follows.

[0193] (1)-1: A surface treatment agent represented by the above formula (1), wherein R in formula (1) is an n-decyl group, and a mixture of a compound with a value of 1 and a compound with a value of 2. (1)-2: A surface treatment agent represented by formula (1) above, wherein R in formula (1) is an n-dodecyl group, and a mixture of a compound with a value of 1 and a compound with a value of 2. (1)-3: A surface treatment agent represented by formula (1) above, wherein R in formula (1) is an oleyl group, and a mixture of a compound with a value of 1 and a compound with a value of 2. (1)-4: A surface treatment agent represented by formula (1) above, wherein R in formula (1) is a stearyl group, and a mixture of a compound with a value of 1 and a compound with a value of 2. (2)-1: A surface treatment agent represented by formula (2) above, wherein R in formula (2) is an n-dodecyl group and a is 1. (2)-2: A surface treatment agent represented by formula (2) above, wherein R in formula (2) is an n-octadecyl group and a is 1. AR-A: Acrylic resin A AR-B: Acrylic resin B AR-C: Acrylic resin C AR-D: Acrylic resin D AR-E: Acrylic resin E AR-F: Acrylic resin F POAA1: A polyoxyalkyleneamine compound represented by the above formula (4), satisfying the condition that m / n is 6.3 between m and n, and having a weight-average molecular weight of 1000. POAA2: A polyoxyalkyleneamine compound represented by formula (4) above, satisfying the condition that m / n is 3.7 between m and n, and having a weight-average molecular weight of 2000. POAA3: A polyoxyalkyleneamine compound represented by formula (4) above, satisfying the condition that m / n is 3.1 between m and n, and having a weight-average molecular weight of 2000. DEDG: Diethylene glycol diethyl ether BTGH: Tetraethylene glycol monobutyl ether γBL: γ-butyrolactone ODTES: Octadecyltriethoxysilane as a surface treatment agent ODCA: Octadecylcarboxylic acid as a surface treatment agent FHP: CF3(CF2)5(CH2)2P(O)-(OH)2 as a surface treatment agent PEs: Polyester with an acid value of 40

[0194] In Tables 2 and 3, the units for the content of each component are in mass percent. Note that POAA1 to POAA3 were all block copolymers in which an amino group was bonded to the end of a continuous oxyethylene unit, and a methyl group was bonded to the end of a continuous oxypropylene unit.

[0195] Furthermore, observations were conducted on 50 arbitrary metal particles of the metal pigments constituting the coloring compositions of each of the above examples. As a result, when observed from the direction that maximizes the projected area, i.e., the area S1 [μm²] when viewed from a planar perspective, 2 ] and the area S0 [μm²] observed from the direction perpendicular to the observation direction that yields the largest observed area. 2 The ratio S1 / S0 to ] was calculated, and the average of these was found to be 19 or greater in all cases.

[0196] The volume-average particle size D50 in the table was measured using a Microtrac MT-3300 (Microtrac-Bell, a laser diffraction / scattering particle size distribution analyzer). Furthermore, the viscosity of the coloring compositions of Examples 1 to 21 at 25°C, measured using a rotational viscometer in accordance with JIS Z8809, was within the range of 1.5 mPa·s to 15 mPa·s. The average thickness of the metallic pigment was measured using the atomic force microscope mentioned earlier.

[0197] [Table 2]

[0198] [Table 3]

[0199] [5] Rating [5-1] Dispersion stability of metal particles Each of the coloring compositions for the above examples and comparative examples was filled into a predetermined ink pack, left in a constant temperature bath at 50°C for 7 days, and then slowly cooled to room temperature.

[0200] Subsequently, these coloring compositions were measured using a particle size analyzer (Microtrac MT3300EXII) to determine the volume-average particle diameter D50 of the metal particles. The increase rate from the volume-average particle diameter D50 of the metal particles contained in the coloring composition before being placed in a constant-temperature bath was determined and evaluated according to the following criteria. A smaller increase rate in volume-average particle diameter D50 indicates better dispersion stability of the metal particles.

[0201] A: The increase rate of the volume-average particle size D50 is less than 3%. B: The increase rate of the volume-average particle diameter D50 is 3% or more but less than 5%. C: The increase rate of the volume-average particle diameter D50 is 5% or more but less than 10%. D: The increase rate of the volume-average particle diameter D50 is 10% or more.

[0202] [5-2] Gloss of the colored body First, using the coloring compositions of each of the above examples and comparative examples, colored bodies were produced as follows.

[0203] Specifically, first, the coloring composition is loaded into an inkjet device, and then, using this inkjet device, 5 mg / inch is infused onto a polyvinyl chloride film (Mactac 5829R, manufactured by Mactac Corporation) which serves as the recording medium. 2 A colored body was obtained by ejecting a coloring composition at a recording resolution of 1440 × 1440 dpi to form a colored area. A modified SC-S606850 inkjet device manufactured by Seiko Epson Corporation was used. This inkjet device has a nozzle density of 360 npi and 360 nozzles in the nozzle row. The recording medium temperature of the platen with the coloring composition attached was 45°C, and the recording medium temperature of the afterheater was 60°C.

[0204] The gloss of the colored portions of the colored bodies obtained in each of the above-described examples and comparative examples was measured at a tilt angle of 60° using a MINOLTA MULTI GLOSS 268 gloss meter and evaluated according to the following criteria. A higher value indicates better gloss. A value of C or higher was considered a good level.

[0205] A: The gloss level is 450 or higher. B: Glossiness is between 430 and 450. C: Glossiness is between 400 and 430. D: Gloss level is less than 400.

[0206] [5-3] Adhesion of the colored area For each of the colored bodies produced in the above [5-2], Cellotape (registered trademark) No. 405 (manufactured by Nichiban Co., Ltd.) was applied to the surface on which the colored portion was provided. Then, it was peeled off at a peeling angle of 180° and a peeling speed of 1 m / min. The gloss of the area where the colored portion was formed was measured at a tilting angle of 60° using a MINOLTA MULTI GLOSS 268 gloss meter. The percentage decrease in gloss from the gloss obtained in the above [5-2] was calculated and evaluated according to the following criteria. A smaller value indicates better adhesion of the colored portion. A value of C or higher was considered a good level.

[0207] A: The decrease in glossiness is less than 5%. B: The decrease in glossiness is 5% or more but less than 10%. C: The decrease in glossiness is between 10% and less than 20%. D: The gloss level has decreased by 20% or more.

[0208] Furthermore, the colored body was manufactured in the same manner as described in [5-2] above, except that a polyethylene terephthalate film (Lintec Corporation, E1000ZC) was used instead of a polyvinyl chloride film (Mactac Corporation, Mactac5829R) as the recording medium. The adhesion of the colored portion of the colored body was also evaluated using the same method and criteria as described above.

[0209] [5-4] Paint film drying properties First, using the coloring compositions of each of the above examples and comparative examples, colored bodies were produced as follows.

[0210] Specifically, first, a coloring composition was applied to a polyvinyl chloride film (Mactac5829R, manufactured by Mactac Corporation) to a thickness of 18 μm using a bar coater #7. Then, it was left to stand at 23°C for 5 minutes.

[0211] Subsequently, a polyvinyl chloride film (Mactac 5829R, manufactured by Mactac) without the coloring composition applied to the side of the colored body manufactured as described above is placed face down, and 2 cm 2 A 100g load was applied to the area, and it was left undisturbed for 15 minutes.

[0212] Subsequently, the layered polyvinyl chloride film without the coloring composition was removed, and the surface of the colored object coated with the coloring composition was visually observed and evaluated according to the following criteria. Less transfer to the back side indicates superior coating drying performance.

[0213] A: There is absolutely no bleed-through. B: Slight bleed-through is visible. C: Some ink bleed-through is visible. D: Significant bleed-through is visible throughout.

[0214] [5-5] Discharge stability A droplet ejection device was prepared in a thermal chamber, and with the drive waveform of the piezoelectric element optimized, droplets of the coloring compositions of each example and comparative example were continuously ejected from all nozzles of a droplet ejection head with a nozzle hole size of 22 μm in diameter under conditions of 25°C and 50% RH. Forty seconds after the start of ejection, droplet flight images were taken, and those where no droplet was visible or where the trajectory was deviated by more than 25% from the trajectory of the initially ejected droplet were counted and grouped together as the number of defective nozzles. The ratio to the total number of nozzles was calculated and evaluated according to the following criteria. A smaller value indicates better ejection stability.

[0215] A: The percentage of defective nozzles is less than 5%. B: The percentage of defective nozzles is between 5% and 10%. C: The percentage of defective nozzles is between 10% and 20%. D: The percentage of defective nozzles is 20% or more. These results are shown in Table 4.

[0216] [Table 4]

[0217] As is clear from Table 4, the examples using the coloring composition of the present invention were all suitable for producing colored bodies that exhibited excellent gloss and excellent adhesion between the workpiece to which the coloring composition was applied and the colored portion formed by the coloring composition. Furthermore, the compositions also exhibited excellent dispersion stability of metal particles, drying properties of the coating film, and discharge stability. In contrast, comparative examples that did not use the coloring composition of the present invention all showed inferiority in either gloss or adhesion.

[0218] Furthermore, the same evaluations as described in [5-2], [5-3], and [5-4] above were performed, except for the use of tarpaulin as the recording medium, and the same results as described above were obtained.

Claims

1. It contains a metal pigment, an acrylic resin with an acid value of 40 mg KOH / g or less, and a liquid medium component. The aforementioned metal pigment consists of a plurality of metal particles, The aforementioned metal particles are surface-modified with a surface treatment agent. A coloring composition comprising at least one compound selected from the group consisting of a compound represented by the following formula (1) and a compound represented by the following formula (2). (R) a P(O)(OH) 3-a (1) (R) a P(O)(OH) 3-a (2) (In the formula, R is a hydrocarbon group having 18 or more carbon atoms, and a is 1 or 2.)

2. The coloring composition according to claim 1, wherein R is a hydrocarbon group having between the number of carbon atoms and 30.

3. The coloring composition according to any one of claims 1 or 2, wherein the acid value of the acrylic resin is 1 mg KOH / g or more and 40 mg KOH / g or less.

4. The coloring composition according to any one of claims 1 to 3, wherein the weight-average molecular weight of the acrylic resin is 5,000 or more and 20,000 or less.

5. The coloring composition according to any one of claims 1 to 4, wherein the proportion of acrylic monomers in the acrylic resin is 90% by mass or more.

6. The coloring composition according to any one of claims 1 to 5, wherein the coloring composition is a solvent-based composition containing an organic solvent as the liquid medium component.

7. The coloring composition according to any one of claims 1 to 6, wherein the metal particles are composed of aluminum or an aluminum alloy.

8. The coloring composition according to any one of claims 1 to 7, wherein the metal particles are in the form of flakes.

9. The coloring composition according to any one of claims 1 to 8, wherein the content of the surface treatment agent is 1.0 part by mass or more and 50 parts by mass or less per 100 parts by mass of the metal particles.

10. The coloring composition according to claim 1, wherein the coloring composition is an inkjet ink composition.

11. A coloring method comprising the step of applying a coloring composition according to any one of claims 1 to 10 to an object to be colored.

12. The coloring method according to claim 11, wherein the step of adhering the coloring composition, which is an inkjet ink composition, is ejected by an inkjet method and adhered to the object to be colored, which is a recording medium.

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