JP2019065229A - Manufacturing method of mixed liquid, system for manufacturing mixture, ink composition, image formation method and image formation article - Google Patents

Abstract

To provide a manufacturing method of a mixture capable of being used for manufacturing an ink composition used for forming a metallic sheen layer having a color tone with wider color zone.SOLUTION: The manufacturing method of a mixture includes a process for mixing a plurality of first metal nanoparticles adding a main color tone to a metallic sheen layer when the metallic sheen layer having sheet resistance of 1×10Ω/sq. and a plurality of second metal nanoparticles of which average particle diameter or metal species constituting the metal nanoparticles are different from the plurality of first metal nanoparticles, and which change the color tone added to the metallic sheen layer by the plurality of first metal nanoparticles, by using the mixture as an ink composition.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method of producing a liquid mixture, a system for producing a liquid mixture, an ink composition, an image forming method and an image formed article.

  Aluminum pigments, pearl pigments and the like are used for the purpose of developing metallic gloss on recorded articles such as labels, packages, public printed matters and photographs. These pigments are applied as ink compositions by analog printing techniques, including offset printing, gravure printing, screen printing, etc., to form areas that emit metallic gloss colors in the recording.

  In recent years, nano-sized particles (hereinafter, also simply referred to as "metal nanoparticles") containing metals such as gold, silver and copper are prepared in order to produce a recorded material in which the area emitting metallic gloss color is made higher definition. A method has been developed which is applied to the surface of a substrate to form a metallic gloss layer containing the metal nanoparticles on the substrate.

  As a method of adjusting the color tone of such a metallic gloss layer, for example, Patent Document 1 applies a coating liquid in which silver fine particles having a uniform particle size distribution of 20 to 100 nm are uniformly dispersed on a substrate at room temperature A silver film having a metallic gloss of gold color obtained by drying is described. Further, in Patent Document 2, metal particles composed of an alloy containing gold (Au) as a main component and silver (Ag), copper (Cu), palladium (Pd) or the like as a secondary component are applied to the substrate surface and dried. A coating film having a color tone such as red gold, pink gold, white gold and the like obtained by

JP, 2009-269935, A Unexamined-Japanese-Patent No. 2006-124826

  However, in the silver film obtained by using the silver fine particles described in Patent Document 1, the color index in the L * a * b * color space (standard light source D65, viewing angle 10 °) is L * value: around 65, a * Only a narrow color tone of around 6 and b * around 20 can be realized. Moreover, in the method of obtaining a coating film using the metal particle which consists of an alloy of patent document 2, it is necessary to produce the metal particle of an alloy in which composition differs in every color tone which should be formed, and a complicated process is needed. .

  This invention is made in view of the said subject, and the manufacturing method of the liquid mixture which can be used for manufacture of the ink composition used for formation of the metallic gloss layer which has a color tone of a wider color range, the said liquid mixture is manufactured. It is an object of the present invention to provide a system, an ink composition containing the mixture, an image forming method using the ink composition, and an image-formed product that can be formed using the ink composition.

One aspect of the present invention for solving the above problems relates to a method for producing a liquid mixture. The method includes applying a main color tone to the metallic gloss layer when the mixture is used as an ink composition to form a metallic gloss layer having a sheet resistance of greater than 1 × 10 ⁵ Ω / sq. The metal nanoparticles of the present invention and the first plurality of metal nanoparticles are a plurality of metal nanoparticles different in particle size distribution or metal species constituting the metal nanoparticles, and the metal of the first plurality of metal nanoparticles Mixing the second plurality of metal nanoparticles for changing the color tone applied to the gloss layer.

Another aspect of the present invention for solving the above problems relates to a system for producing a mixed solution. The system imparts a main color tone to the metallic gloss layer when a mixture container and the mixture liquid form an ink composition to form a metallic gloss layer having a sheet resistance of more than 1 × 10 ⁵ Ω / sq. A plurality of metal nanoparticles different in particle size distribution or metal species constituting the metal nanoparticles from a first input portion for charging the first plurality of metal nanoparticles into the mixing container and the first plurality of metal nanoparticles And a second charging unit for charging a second plurality of metal nanoparticles for changing the color tone to be imparted to the metallic gloss layer by the first plurality of metal nanoparticles into the mixing container.

Yet another aspect of the present invention for solving the above problems relates to an ink composition for forming a metallic gloss layer having a sheet resistance of more than 1 × 10 ⁵ Ω / sq. In the ink composition, the first plurality of metal nanoparticles imparting a main color tone to the metallic gloss layer and the first plurality of metal nanoparticles differ in the particle size distribution or the metal species constituting the metal nanoparticles. A plurality of metal nanoparticles, and a second plurality of metal nanoparticles for changing the color tone imparted to the metallic gloss layer by the first plurality of metal nanoparticles.

  Yet another aspect of the present invention for solving the above problems relates to an image forming method comprising the steps of applying the above ink composition onto a substrate and drying it.

Yet another aspect of the present invention for solving the above problems relates to an image forming material comprising a metallic gloss layer having a sheet resistance of more than 1 × 10 ⁵ Ω / sq. In the metal gloss layer, the first plurality of metal nanoparticles imparting a main color tone to the metal gloss layer and the first plurality of metal nanoparticles differ in the particle size distribution or in the metal species constituting the metal nanoparticles. A plurality of metal nanoparticles, and a second plurality of metal nanoparticles for changing the color tone imparted to the metallic gloss layer by the first plurality of metal nanoparticles.

  A method of producing a liquid mixture that can be used to produce an ink composition used to form a metallic gloss layer having a wider color tone according to the present invention, a system for producing the liquid mixture, and an ink composition containing the liquid mixture And an image forming method using the ink composition, and an image forming product that can be formed using the ink composition.

FIG. 1 is a flow chart showing an exemplary method of producing a mixture according to an embodiment of the present invention. FIG. 2 is a flow chart illustrating an exemplary method of manufacturing an ink composition according to another embodiment of the present invention. FIG. 3 is a schematic view showing an outline of a system for producing a mixed solution. FIG. 4 is a schematic view showing an outline of a system for producing an ink composition.

  The present inventors have conducted intensive studies in view of the above problems, and the first plurality of metal nanoparticles giving the main color tone to the metallic gloss layer, the first plurality of metal nanoparticles have a particle size distribution or metal nanoparticles. It has been found that the color tone imparted by the first plurality of metal nanoparticles can be changed by combining and using the second plurality of metal nanoparticles having different metal species, and the present invention is It was completed.

  Since the metallic gloss layer can be presumed to be a substantially smooth surface, the color tone (specular reflection spectrum) of the metallic gloss layer depends on the optical constants (refractive index and extinction coefficient) of the material constituting the metallic gloss layer Then you can guess. It is also known that the refractive index and extinction coefficient of nanoparticles vary depending on the particle size of the nanoparticles and the metal type. Furthermore, the optical constant of the composite in which a plurality of nanoparticles are mixed includes the dielectric constant of each nanoparticle (the square of the refractive index) and the dielectric constant of other components (additives) such as a binder resin, and these components It can be considered to be a value calculated by the effective medium approximation based on the volume fraction of

  That is, in addition to the first plurality of metal nanoparticles that are more abundant in the metallic gloss layer, the second plurality of metal nanoparticles that are present in the same amount or less than the first plurality of metal nanoparticles, The color tone of the metallic gloss layer is a color tone that is changed to a degree according to the particle size distribution or metal species of the second plurality of metal nanoparticles, with respect to the color tone provided by the first plurality of metal nanoparticles. In the present specification, the particle size distribution of the first plurality of metal nanoparticles or the second plurality of metal nanoparticles is a concept including at least the average particle diameter of the metal nanoparticles and the half width at the peak.

  The present invention has been made based on this idea, and the color tone imparted to the metallic gloss layer by the first plurality of metal nanoparticles is different from that of the first plurality of metal nanoparticles in particle size distribution or metal nano particles. The color tone of the metallic gloss layer is adjusted to a desired color tone by changing the metal species of the particles with a second plurality of different metal nanoparticles.

  Specifically, the color tone of the metallic luster layer containing the first plurality of metal nanoparticles and the second plurality of metal nanoparticles (hereinafter collectively referred to simply as "metal nanoparticles") is effective as described above. It can be estimated qualitatively by calculation using medium approximation, but quantitatively it is estimated using the particle size distribution (volume fraction per particle diameter) and optical constants of metal nanoparticles by electromagnetic field optical simulation FDTD method be able to. In addition, the correspondence relationship between the specific combination of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles and the color tone of the metallic gloss layer realized by the combination is obtained in advance, Referring to the relationship, the combination of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles for achieving a desired color tone can also be used to form a metallic gloss layer.

  From the viewpoint of enabling control of color tone by such a combination of metal nanoparticles, in the metallic gloss layer, voids are formed between the metal nanoparticles without welding and sintering of a plurality of metal nanoparticles. Is desired. As such, the metal former can be formed by applying an ink composition comprising the first plurality of metal nanoparticles and the second plurality of metal nanoparticles onto the substrate, and then applying the first plurality of metal nanoparticles and the second plurality of metal nanoparticles. It is desirable to dry the ink composition by heating to a temperature at which the plurality of metal nanoparticles do not melt.

In the metallic luster layer formed in this manner, the sheet resistance of the metallic luster layer is 1 × 10 ⁵ Ω / sq, since a reduction in sheet resistance due to welding or sintering of metal nanoparticles is unlikely to occur. It gets bigger. In addition, as long as the sheet resistance of the laminate is greater than 1 × 10 ⁵ Ω / sq, some of the metal nanoparticles may be sintered, welded, or in contact with each other. The said sheet resistance can be made into the value obtained by measuring by a contact type (4 probe method) using a well-known volume resistivity measuring device.

According to the studies and experiments of the present inventors, the second plurality of metal nanoparticles, if appropriately selected, have the color tone of the metallic gloss layer formed using only the first plurality of metal nanoparticles, The distance on the color coordinates (u ′, v ′) in the CIE 1976 UCS chromaticity diagram (2 ° visual field) is 0.001 or more and 0.05 or less, preferably 0.001 or more and 0.02 or less, more preferably 0. It is possible to change the color tone to a distance of 002 or more and 0.015 or less, more preferably 0.002 or more and 0.01 or less, and particularly preferably 0.005 or more and 0.01 or less. Note that the distance on the color coordinates (u ', v') is a value obtained by ((absolute value of difference of values of u ') ² + (absolute value of difference of values of v' ² ) ² ) It is.

  Also, according to the studies and experiments of the present inventors, the combination of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles makes the color tone of the metallic gloss layer more metallic. Adjust the color coordinates (u ', v') in the CIE 1976 UCS chromaticity diagram (2 ° visual field) in the range of 0.19 <u '<0.27 and 0.45 <v' <0.57 can do.

  The color coordinates (u ', v') in the CIE 1976 UCS chromaticity diagram (2 ° visual field) can be measured by the method described in JIS Z 8781-5.

  Each of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles is a nanoparticle composed mainly of metal atoms. Examples of such metals include gold, silver, copper, nickel, palladium, platinum, aluminum, zinc, chromium, iron, cobalt, molybdenum, zirconium, ruthenium, iridium, tantalum, mercury, indium, tin, lead, and tungsten, and These alloys are included. Among them, gold, silver, copper, nickel, cobalt, tin, lead, chromium, zinc and aluminum are preferable because they can express high gloss and are inexpensive, and gold, silver, copper, tin, Chromium, lead and aluminum are more preferred, gold, silver and copper are more preferred, and silver is particularly preferred. The metal nanoparticles may have these metals as main components, may contain other components inevitably contained in a small amount, and are surface-treated with citric acid or the like to enhance the dispersion stability. It is also good.

  The average particle size of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles is not particularly limited, but enhances the dispersion stability and storage stability in the composition for producing the metallic gloss layer From the viewpoint, all of them are preferably 3 nm or more and 100 nm or less, and more preferably 20 nm or more and 75 nm or less. When the average particle size is 3 nm or more, preparation of metal nanoparticles and control of particle size distribution are easy. If the average particle diameter is 100 nm or less, irregular reflection of light incident on the metallic gloss layer can be suppressed to form a metallic gloss layer having a smoother appearance, and the smoothness of the metallic gloss layer can be enhanced, and the ink composition The dispersibility of the metal nanoparticles in it can be enhanced. The average particle size of the metal nanoparticles can be a volume average particle size obtained from a scanning electron microscope (SEM) image.

  In addition, the first plurality of metal nanoparticles and the second plurality of metal nanoparticles are preferably metal nanoparticles that receive electromagnetic waves in the visible light region to generate surface plasmon resonance. Such metal nanoparticles can cause absorption and scattering of light derived from surface plasmon resonance to further widen the color tone that the metallic gloss layer may have. In particular, when the second plurality of metal nanoparticles receive an electromagnetic wave in the visible light region to generate surface plasmon resonance, the second plurality of metal nanoparticles are absorbed and scattered by the light from the surface plasmon resonance to form the first plurality of metal nanoparticles. The color tone to be applied can be changed in more various directions. From such a point of view, it is preferable that at least the second plurality of metal nanoparticles be metal nanoparticles that receive an electromagnetic wave in the visible light range to generate surface plasmon resonance, and the first plurality of metal nanoparticles and the second plurality of metal nanoparticles The average particle diameter of the plurality of metal nanoparticles is more preferably metal nanoparticles that receive electromagnetic waves in the visible light range to generate surface plasmon resonance.

  For example, when the second plurality of metal nanoparticles are silver particles, if the average particle diameter of the second plurality of metal nanoparticles is 20 nm or 30 nm or less, absorption of short wavelength light by surface plasmon resonance is increased. Changing the color tone of the metallic gloss layer to a warmer color system (in the direction in which u 'and v' of color coordinates (u ', v') in the CIE 1976 UCS chromaticity diagram (2 ° view) both increase) Can.

  On the other hand, when the second plurality of metal nanoparticles is a silver particle, if the average particle diameter of the second plurality of metal nanoparticles is 35 nm or more and 75 nm or less, absorption of light of a specific wavelength by surface plasmon resonance Reduces the color tone of the metallic luster layer to a color closer to the bulk metal (in the CIE 1976 UCS chromaticity diagram (2 ° view), the u 'and v' of the color coordinates (u ', v') both decrease) Can be changed).

  The second plurality of metal nanoparticles may be different from the first plurality of metal nanoparticles in at least the particle size distribution or the metal species constituting the metal nanoparticles constituting the metal nanoparticles. In addition, the second plurality of metal nanoparticles may be used in combination of a plurality of types of metal nanoparticles having different particle sizes or constituent metal species.

  When the second plurality of metal nanoparticles differ from the first plurality of metal nanoparticles, the average particle diameter preferably differs by 15 nm or more and 55 nm or less, more preferably 15 nm or more and 50 nm or less, and more preferably 15 nm More preferably, the difference is 45 nm or less. When the difference in average particle size is in the above-mentioned range, it is possible to change the color tone of the metallic gloss layer more largely from the color tone imparted by the first plurality of metal nanoparticles.

  The difference in the particle size distribution of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles means that the particle size of an image-forming material, an ink composition, or a liquid mixture for producing the ink composition containing them. It means that the distribution will be different from the particle size distribution of the image forming material, the ink composition or the mixture for producing the ink composition containing only the first metal nanoparticles. At this time, for example, in the particle size distribution of the image forming material including the first plurality of metal nanoparticles and the second plurality of metal nanoparticles, each of the first plurality of metal nanoparticles and the second plurality of metals is used. It is only necessary to see two or more peaks across valleys originating from any of the nanoparticles. The term “valley” means that, between adjacent peaks, there is a particle diameter such that the number of particles is 60% or less as compared to the number of particles of the peak having a smaller number of adjacent peaks. Alternatively, the half width at half maximum of the peak of the particle size distribution of the image forming material or the like including the first plurality of metal nanoparticles and the second plurality of metal nanoparticles is an image formation or the like including only the first plurality of metal nanoparticles The second plurality of metal nanoparticles may be changed as compared to the half width at half maximum of the particle size distribution. The particle size distribution can be measured from the SEM image. At this time, it is preferable that the half width at half maximum of each of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles is 5 nm or more and 45 nm or less.

  When the metal species of the second plurality of metal nanoparticles are different from those of the first plurality of metal nanoparticles, the metal species of the first plurality of metal nanoparticles have an absorption wavelength of It is preferable that the metal species having a different spectral shape is the metal species constituting the second plurality of metal nanoparticles. For example, when the metal species that make up the first plurality of metal nanoparticles are silver, the metal species that make up the second plurality of metal nanoparticles can be copper. The metal species constituting the first plurality of metal nanoparticles and the second plurality of metal nanoparticles are characterized and quantified by known methods such as inductively coupled plasma mass spectrometry (ICP-MS) and fluorescent X-ray analysis. can do.

1. Method of Producing Mixed Liquid An embodiment of the present invention relates to a method of producing a mixed liquid used for producing an ink composition for forming the metallic gloss layer.

  The metallic gloss layer may be formed by independently applying the first plurality of metal nanoparticles and the second plurality of metal nanoparticles on a substrate. On the other hand, the first plurality of metal nanoparticles and the second plurality of metal nanoparticles are sufficiently dispersed with each other to form a color tone of the formed metallic gloss layer and a color tone predicted from the combination of the metal nanoparticles. From the viewpoint of suppressing the misalignment, it is preferable to form a one-component ink composition including the first plurality of metal nanoparticles and the second plurality of metal nanoparticles on a substrate and dry it. .

  The one-component ink composition (hereinafter, simply referred to as “ink composition” means the one-component ink composition) includes, for example, the first plurality of metal nanoparticles and the second plurality of metal nanoparticles. The mixture liquid which disperse | distributed the several metal nanoparticle, the dispersion medium, and the additive added arbitrarily can be mixed and manufactured.

  FIG. 1 is a flow chart showing an exemplary method for producing a mixed liquid according to the present embodiment.

1-1. Determination of Combination of Metal Nanoparticles In an exemplary method of producing a mixed liquid according to the present embodiment, first, a first plurality of metal nanoparticles and a second plurality of metal nanoparticles are determined (step S100).

  The metal species constituting the metal nanoparticles of the first plurality of metal nanoparticles may be selected from metals which impart the main color tone of the metallic gloss layer formed by the ink composition. For example, when it is intended to form a silver-based metallic gloss layer, the first plurality of metal nanoparticles may be a plurality of metallic nanoparticles composed of silver, and a gold-based metallic gloss layer may be formed. When it is assumed that the first plurality of metal nanoparticles may be a plurality of metal nanoparticles that are metal atoms composed of gold, and when it is intended to form a copper-based metal gloss layer, The plurality of metal nanoparticles may be a plurality of metal nanoparticles which are metal atoms composed of copper.

  Furthermore, according to the color tone of the metallic gloss layer formed by the ink composition, the particle size distribution of the first plurality of metal nanoparticles, the metal species constituting the second plurality of metal nanoparticles, the second plurality of The particle size distribution of the metal nanoparticles and the mixing ratio of each of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles in the ink composition are determined.

At this time, for the particle size distribution or the plurality of combinations of metal nanoparticles having different metal species constituting the metal nanoparticles, the correspondence relationship is listed, in which the values calculated by the above-described effective medium approximation or FDTD are listed. The combination of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles may be determined so as to realize the color tone of the formed metallic gloss layer or a color tone close thereto. At this time, a combination of metal nanoparticles different in particle size distribution or metal species constituting the metal nanoparticles, and a color tone of a metallic gloss layer having a sheet resistance realized by the combination of more than 1 × 10 ⁵ Ω / sq. The correspondence relationship of and is previously obtained by experiment etc., and the first plurality of metal nano-sheets are realized so as to realize the color tone of the formed metallic gloss layer or the color tone similar thereto with reference to the above-mentioned correspondence relationship. The combination of the particle and the second plurality of metal nanoparticles may be determined.

The first plurality of metal nanoparticles and the second plurality of metal nanoparticles are applied onto a substrate and dried to form a metallic gloss layer having a sheet resistance greater than 1 × 10 ⁵ Ω / sq. The color coordinates (u ′, v ′) in the CIE 1976 UCS chromaticity diagram (2 ° visual field) are 0.19 <u ′ <0.27 and 0.45 <v ′ <0.57. The metal nanoparticles can be selected to constitute a combination capable of forming a metallic gloss layer included in the range of.

In addition, the second plurality of metal nanoparticles is a color coordinate (u ′,) in the CIE 1976 UCS chromaticity diagram (2 ° view) in the color tone of the metallic gloss layer imparted by the first plurality of metal nanoparticles. It is preferable to select one that changes the color tone so that the distance on v ′) is 0.001 or more and 0.05 or less. The degree to which the color tone is changed is the color tone of a metallic gloss layer having a sheet resistance of greater than 1 × 10 ⁵ Ω / sq, formed using only the first plurality of metal nanoparticles as the metal nanoparticles, It can be a difference between the first metallic nanoparticles and the second metallic nanoparticles and the color tone of the metallic gloss layer having a sheet resistance of more than 1 × 10 ⁵ Ω / sq. .

1-2. Next, the first plurality of metal nanoparticles and the second plurality of metal nanoparticles determined above are mixed to produce a mixed solution (S200).

  The first plurality of metal nanoparticles and the second plurality of metal nanoparticles are preferably mixed in the dispersion medium to be the liquid component of the ink composition.

  The metal nanoparticles may be used to constitute a combination of the above determined first plurality of metal nanoparticles and the second plurality of metal nanoparticles when mixed. For example, a plurality of metal nanoparticles satisfying the condition of the first plurality of metal nanoparticles determined above and a plurality of metal nanoparticles satisfying the conditions of the second plurality of metal nanoparticles determined above are mixed do it. A commercially available thing may be used for a metal nanoparticle, and what was mixed so that it may become the said combination may be used.

  As described above, the average particle diameter of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles is preferably 3 nm or more and 100 nm or less.

  Also, as described above, from the viewpoint of further widening the color tone that the metallic gloss layer may have, the first plurality of metal nanoparticles and the second plurality of metal nanoparticles are at least a second plurality of metal nano-particles. The average particle size of the particles is preferably 20 nm or more and 75 nm or less, and the average particle sizes of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles are more preferably 20 nm or more and 75 nm or less .

  In addition, as described above, from the viewpoint of changing the color tone of the metallic gloss layer to a warmer color, when the second plurality of metal nanoparticles are silver particles, the average particle diameter of the second plurality of metal nanoparticles Is preferably 20 nm or less and 30 nm or less. On the other hand, from the viewpoint of changing the color tone of the metallic gloss layer to the color tone of the bulk metal, the average particle diameter of the second plurality of metal nanoparticles is preferably 35 nm or more and 75 nm or less.

  Further, as described above, from the viewpoint of largely changing the color tone of the metallic gloss layer from the color tone imparted by the first plurality of metal nanoparticles, the second plurality of metal nanoparticles is the first plurality of metal nanoparticles. The metal nanoparticles preferably have an average particle size different from 15 nm to 55 nm, more preferably 15 nm to 50 nm, still more preferably 15 nm to 45 nm.

  Also, as described above, the second plurality of metal nanoparticles constitute the first plurality of metal nanoparticles when the metal species constituting the metal nanoparticles are different from the first plurality of metal nanoparticles. It is preferable that the second plurality of metal nanoparticles be composed of a metal species that is different from the metal species in the spectrum shape of the absorption wavelength. For example, when the metal species that make up the first plurality of metal nanoparticles are silver, the metal species that make up the second plurality of metal nanoparticles can be copper.

  In addition, in order to improve the dispersibility of metal nanoparticles, a metal dispersing agent may be adsorb | sucking on the surface of a metal nanoparticle.

  The polymeric dispersant has an adsorptive group for adsorbing to the surface of the metal nanoparticles. The above-mentioned adsorption group should just be a functional group which has strong adsorption power to the surface of metal particles. Examples of the above-mentioned adsorptive groups include primary to tertiary amino groups, quaternary ammonium groups, heterocyclic groups having a basic nitrogen atom, hydroxyl groups, carbonyl groups, carboxyl groups, phosphoric acid groups, sulfonic acid groups, And thiol groups.

  The resin constituting the polymer dispersant is preferably a homopolymer or copolymer of a hydrophilic monomer. The copolymer of the hydrophilic monomer may be a copolymer of a hydrophilic monomer and a hydrophobic monomer.

  Examples of hydrophilic monomers include monomers containing a carboxyl group or an acid anhydride group ((meth) acrylic acid, unsaturated polyvalent carboxylic acids such as maleic acid, and maleic anhydride, etc.), and alkylene oxide modified (meth) And acrylic acid ester monomers (such as ethylene oxide modified (meth) acrylic acid alkyl ester) and the like. In the present invention, (meth) acrylic means acrylic and / or methacrylic.

  Examples of hydrophobic monomers include (meth) acrylate monomers such as methyl (meth) acrylate and ethyl (meth) acrylate, styrene monomers such as styrene, α-methylstyrene and vinyltoluene, ethylene, propylene And α-olefin monomers such as 1-butene, and carboxylic acid vinyl ester monomers such as vinyl acetate and vinyl butyrate.

  The polymer dispersant preferably has an acid value. Examples of polymer dispersants having an acid value include polymer dispersants having a carboxyl group, a phosphate group, a sulfonate group, and the like as an adsorptive group or a functional group. The acidic group is preferably a carboxyl group or a phosphoric acid group, more preferably a carboxyl group.

  The polymer dispersant preferably has an acid value of 1 mg KOH / g or more and 100 mg KOH / g or less. When the acid value is 1 mg KOH / g or more, the polymer dispersant has a tendency to be hydrophilic, so that the dispersibility of metal nanoparticles in an aqueous ink composition can be particularly enhanced, and the ink by the inkjet method The ejection stability (dispersion stability) of the water-based ink composition when used as a composition can also be further enhanced. On the other hand, when the above-mentioned acid value is 100 mg KOH / g or less, it is also possible to suppress a remarkable drop in the ejection stability (dispersion stability) from the inkjet head due to the swelling of the polymer dispersant in the inkjet head. it can. From the above viewpoint, the acid value of the polymer dispersant is preferably 3 mg KOH / g to 80 mg KOH / g, more preferably 5 mg KOH / g to 60 mg KOH / g, and 7 mg KOH / g to 50 mg KOH / g. It is further preferred that

The acid value of the polymer dispersant may be measured according to JIS K 0070 using a stoichiometric method such as neutralization titration. In addition, the type of dispersant may be identified by Fourier transform infrared spectroscopy (FT-IR), ¹ H-NMR and gas chromatography-mass spectrometry (GC / MS).

  The weight average molecular weight of the polymer dispersant is preferably 1,000 or more and 100,000 or less, and more preferably 2,000 or more and 50,000 or less.

  The content of the polymer dispersant is not particularly limited, but from the viewpoint of sufficiently enhancing the dispersibility of the metal nanoparticles in the ink composition and the adhesion to the substrate, relative to the total mass of the metal nanoparticles, The content is preferably 1% by mass to 15% by mass, more preferably 2% by mass to 10% by mass, and still more preferably 3% by mass to 8% by mass.

  The liquid mixture produced in this manner can be used as it is as an ink composition to form a metallic gloss layer. At this time, metal nanoparticles, a dispersion medium (described later), and an additive (described later) optionally added may be mixed in this step.

  In addition, as described later, after the above-mentioned mixed liquid is manufactured, a dispersion medium and an additive which is optionally added may be added to the above mixed liquid to make an ink composition. When a dispersion medium and an additive are added to the above mixed liquid to form an ink composition, when the ink composition contains a surfactant (surface conditioner), the surfactant is added to the metal nanoparticles in this step. It is preferable to mix and produce the liquid mixture containing surfactant.

  Examples of surfactants include anionic surfactants such as dialkyl sulfosuccinates, alkyl naphthalene sulfonates and fatty acid salts, polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, acetylene glycols and polyoxy acids It includes nonionic surfactants such as ethylene / polyoxypropylene block copolymers, cationic surfactants such as alkylamine salts and quaternary ammonium salts, and surfactants of silicone type and fluorine type.

  The content of the surfactant can be, for example, 0.001% by mass or more and less than 1.0% by mass with respect to the total mass of the ink composition.

1-3. Production of Ink Composition The above-mentioned mixed liquid can be mixed with a dispersion medium to be a liquid component of the ink composition and an additive which is optionally added to form an ink composition.

  FIG. 2 is a flow chart showing an exemplary method of producing the ink composition according to the present embodiment. In addition, since step S100 and step S200 can be performed similarly to the manufacturing method of the said liquid mixture, the overlapping description is abbreviate | omitted.

1-3-1. Mixture of Dispersion Medium After the above mixed liquid is manufactured, a dispersion medium is added to the manufactured mixed liquid, and the above mixed liquid and dispersion medium are mixed to prepare a dispersion having a viscosity suitable as an ink composition. (Step S300).

  The dispersion medium may be water or an organic solvent as long as it can disperse metal particles of nanosize, but water is preferable in terms of safety to human body and easiness of processing. However, even when water is used as the dispersion medium, a known organic solvent may optionally be contained for viscosity adjustment and the like. Examples of organic solvents include polyhydric alcohols, polyhydric alcohol derivatives, alcohols, amides, ketones, keto alcohols, ethers, nitrogen-containing solvents, sulfur-containing solvents, propylene carbonate, ethylene carbonate, and 1,3-dimethyl -2- And imidazolidinone and the like. Examples of the polyhydric alcohol include glycerin, ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, hexylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, trimethylolpropane, 1, 5-pentanediol, 1,2,6-hexanetriol and the like are included. Examples of the polyhydric alcohol derivative include ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether, ethylene glycol n-butyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol n-propyl ether, Diethylene glycol n-butyl ether, diethylene glycol n-hexyl ether, triethylene glycol methyl ether, triethylene glycol ethyl ether, triethylene glycol n-propyl ether, triethylene glycol n-butyl ether, propylene glycol methyl ether, propylene glycol ethyl Ether, propylene glycol-n-propyl ether Propylene glycol n-butyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol n-propyl ether, dipropylene glycol n-butyl ether, tripropylene glycol methyl ether, tripropylene glycol ethyl ether, tripropylene Glycol-n-propyl ether, tripropylene glycol-n-butyl ether and the like are included. Examples of the alcohol include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, isobutyl alcohol, tert-butyl alcohol, and benzyl alcohol. Examples of the above amides include dimethylformamide, dimethylacetamide and the like. Examples of the above ketone include acetone and the like. Examples of the keto alcohol include diacetone alcohol and the like. Examples of the above ether include tetrahydrofuran, dioxane and the like. Examples of the nitrogen solvent include pyrrolidone, 2-pyrrolidone, N-methyl-2-pyrrolidone, cyclohexyl pyrrolidone, and triethanolamine. Examples of the above-mentioned sulfur-containing solvents include thiodiethanol, thiodiglycol, thiodiglycerol, sulfolane, dimethyl sulfoxide and the like.

  From the viewpoint of further enhancing the dispersibility of the metal nanoparticles and the binder resin etc. optionally added, the organic solvent is preferably the polyhydric alcohol derivative.

  In addition, when producing an inkjet ink composition capable of image formation by an inkjet method, the organic solvent has a boiling point of 100 from the viewpoint of preventing a decrease in ejection stability due to volatilization by a nozzle at the time of ejection from an inkjet head. It is preferable that it is (degreeC) -350 degreeC, and it is more preferable that it is 200-350 degreeC.

  The amount of dispersion medium may be such that the viscosity of the ink composition to be produced is achieved. For example, when an inkjet ink composition is produced, a dispersion medium may be added and mixed in such an amount that the viscosity of the ink composition is 1 cP or more and less than 100 cP.

1-3-2. Additive Additives such as binder resin may be added to the dispersion liquid, and the dispersion liquid and the additive may be mixed to prepare an ink composition having desired characteristics (Step S400).

  The binder resin can interact with the metal nanoparticles, particularly the dispersant adsorbed on the surface of the metal nanoparticles, to enhance the adhesion of the metal nanoparticles to the substrate. The binder resin is preferably a resin having high affinity to the dispersant, and (meth) acrylic resin, urethane resin, polyolefin resin, polyester resin, polyvinyl chloride resin (for example, polyvinyl chloride polymer, and vinyl chloride- Vinylidene chloride copolymer etc.), epoxy resin, polysiloxane resin, fluorine resin, styrene copolymer (eg styrene-butadiene copolymer, styrene- (meth) acrylate copolymer etc.), and vinyl acetate co-polymer Polymers (for example, ethylene-vinyl acetate copolymer etc.) etc. are included. From the viewpoint of further improving the water resistance of the metallic gloss layer, the binder resin is (meth) acrylic resin, urethane resin, polyolefin resin, polyvinyl chloride resin, epoxy resin, polysiloxane resin, fluorine resin, styrene copolymer), Vinyl acetate copolymers are preferred, and urethane resins and (meth) acrylic resins are more preferred. These binder resins can be used alone or in combination of two or more.

  The content (total mass) of the binder resin is, for example, when the metal nanoparticles are silver nanoparticles, from the viewpoint of suppressing a decrease in the brightness of the metallic gloss layer due to absorption and scattering of light by the binder resin. It is preferable that it is 1/5 or less with respect to the total mass of a metal nanoparticle, It is more preferable that it is 1/7 or less, It is more preferable that it is 1/10 or less.

  However, from the viewpoint of further increasing the reflectance of the metallic gloss layer, the ink composition substantially comprises metal nanoparticles adsorbed by the above-mentioned polymer dispersant, the above-mentioned binder resin and dispersion medium, and optionally a necessary amount of surface activity. It is preferable to consist of an agent. The total content of the metal nanoparticles adsorbed by the polymer dispersant, the binder resin, and the dispersion medium is preferably 90% by mass to 100% by mass with respect to the total mass of the ink composition, and 95 It is more preferable that the content is 100% by mass or more.

  When the ink composition contains a surfactant, the dispersion and the surfactant may be mixed in this step.

2. System for Producing Mixed Liquid and System for Producing Ink Composition 2-1. System for Producing Mixed Liquid Another embodiment of the present invention relates to a system for producing the above mixed liquid.

  FIG. 3 is a schematic view showing an outline of a system 100 for producing the mixed solution. The system 100 includes a mixing device 110, an input unit 140, a storage unit 150, a determination unit 160, and a control unit 170.

  The mixing apparatus 110 includes a mixing vessel 112, and a plurality of metal nanoparticle inputs 114a, 114b and 114c for charging metal nanoparticles into the mixing vessel 100.

  The mixing container 112 is in communication with the plurality of metal nanoparticle input parts 114a, 114b and 114c, and a plurality of types of metal nanoparticles input from these input parts are mixed to form a mixed liquid. The mixing vessel may have a stirring blade 116 for stirring and mixing a plurality of charged metal nanoparticles.

  Each of the metal nanoparticle input parts 114a, 114b and 114c includes a metal nanoparticle tank for storing the metal nanoparticles to be input, a metal nanoparticle channel for connecting the metal nanoparticle tank and the mixing container 112, and a metal. And a metal nanoparticle channel valve for opening and closing the nanoparticle channel to control the input of metal nanoparticles from the respective metal nanoparticle tank into the mixing vessel 112. Although three metal nanoparticle inputs 114a, 114b and 114c are described in FIG. 3, two or more metal nanoparticle inputs may be required, and four, five or more mixing devices 110 may be used. The metal nanoparticle input part of

  In each metal nanoparticle tank, a plurality of metal nanoparticles having different particle sizes or metal species constituting the metal nanoparticles are stored. The metal nanoparticles in each metal nanoparticle tank are preferably dispersed by the same liquid as the dispersion medium that is the liquid component of the ink composition, from the viewpoint of facilitating loading and mixing.

  The input unit 140 includes various operation keys such as a ten key, a start key, an audio receiving unit, or a video receiving unit such as a camera, and receives various input operations by the user to form a metallic gloss layer formed of an ink composition. The color tone to be possessed is output to the determination unit 160. The input unit 140 may be various signal receiving devices configured to receive input data electrically output from another medium, such as a receiving connector, and to be able to output the input data to the determining unit 160. The input data output from the input unit 140 is output to the determination unit 160 and used to determine the first plurality of metal nanoparticles and the second plurality of metal nanoparticles.

The storage unit 150 includes, for example, various storage media such as ROM, RAM, magnetic disk, HDD, and SSD, and a combination of metal nanoparticles and a sheet resistance of 1 × 10 ⁵ Ω / sq realized by the combination. The correspondence with the color tone of the larger metallic gloss layer is stored. In addition, the storage unit 150 stores information such as the particle size distribution and the metal species that constitute the metal nanoparticles, regarding the metal nanoparticles that each of the metal nanoparticle input units 114a, 114b, and 114c stores in the metal nanoparticle tank.

The correspondence relationship may be a list of values calculated by the above-described effective medium approximation or FDTD for a plurality of combinations of metal nanoparticles having different particle types, such as particle size distribution or metal nanoparticles. Also, the above-mentioned correspondence relationship formed a metallic gloss layer having a sheet resistance of more than 1 × 10 ⁵ Ω / sq for a plurality of combinations of metal nanoparticles different in particle size distribution or metal nanoparticles constituting the metal nanoparticles. The color tone of the time may be obtained in advance by experiment or the like, and the combination may be made to correspond to the color tone to make a list.

  The determination unit 160 is configured of a hardware processor such as a central processing unit, and receives the data output from the input unit 140, and the first plurality of metals are determined based on the color tone that the metal gloss layer should have. Determine the nanoparticles and the second plurality of metal nanoparticles. After that, the determination unit 160 refers to the information on the correspondence stored in the storage unit 150 to obtain the first plurality of metal nanoparticles that realize the color tone that the metal gloss layer should have or a color tone similar thereto. And the combination of the second plurality of metal nanoparticles. The determination unit 160 outputs the determined combination to the control unit 170.

  The control unit 170 is configured of a hardware processor such as a central processing unit, and is determined based on the combination of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles determined by the determination unit 160. Decide what kind of composition of liquid mixture should be produced. Furthermore, the control unit 170 refers to the information on the metal nanoparticles stored in each of the metal nanoparticle tanks stored in the storage unit 150 to determine which metal nanoparticles are stored in any metal nanoparticle tank. Decide whether to mix in proportions.

  Further, the control unit 170 opens the metal nanoparticle flow path valve provided in the metal nanoparticle charging unit for storing the metal nanoparticles to be charged in the metal nanoparticle tank among the metal nanoparticle charging units 114a, 114b and 114c. A plurality of types of metal nanoparticles are introduced into the mixing container 112 such that the composition of the mixture determined above is realized. After charging, the control unit 170 rotates the stirring blade 116 of the mixing container 112 to mix the plurality of types of metal nanoparticles that have been charged, thereby forming a mixed liquid.

  The manufactured mixed solution is discharged from the mixing container 112 and collected in a storage container or the like.

  The liquid mixture produced in this manner can be used as it is as an ink composition to form a metallic gloss layer. At this time, the mixing apparatus 110 has respective charging units for charging the dispersion medium and the additive such as the surfactant and the binder resin into the mixing container 112, and the control unit 170 sets the mixing liquid as the ink composition. Depending on the composition, the input of the dispersion medium and the additive may be controlled from these input parts to the mixing vessel 112.

  In addition, as described later, after the above-mentioned mixed liquid is manufactured, a dispersion medium and an additive which is optionally added may be added to the above mixed liquid to make an ink composition. When the dispersion medium and the additive are added to the above mixed liquid to form an ink composition, if the ink composition contains a surfactant, the mixing apparatus 110 charges the surfactant into the mixing container 112. The control unit 170 may control the charging of the surfactant from the charging unit to the mixing container 112.

2-2. System for Producing Ink Composition FIG. 4 is a schematic view showing an outline of a system 200 for producing an ink composition, which has a mixing device 110 for producing a mixed liquid. The system 200 includes the mixing device 100 described above, a dispersion medium mixing device 120, and an additive mixing device 130.

  The dispersion medium mixing device 120 has a dispersion medium mixing vessel 122 and a dispersion medium charging unit 124 for charging the dispersion medium into the dispersion medium mixing vessel 122.

  The dispersion medium mixing container 122 is in communication with the mixing container 112 of the mixing apparatus 110 and in communication with the dispersion medium input unit 124, and mixes the liquid mixture and the dispersion medium flowing from the mixing container 112, Make a dispersion. The dispersion medium mixing container 122 may have a stirring blade 126 for stirring and mixing the mixture liquid and the dispersion medium which have been input.

  The dispersion medium input unit 124 opens and closes the dispersion medium channel for storing the dispersion medium to be input, the dispersion medium channel connecting the dispersion medium tank and the dispersion medium mixing container 122, and the dispersion medium channel. And a dispersion medium channel valve for controlling the input of the dispersion medium from the dispersion medium tank to the dispersion medium mixing container 122.

  The additive mixing device 130 has an additive mixing container 132 and an additive feeding portion 134 for charging the additive into the additive mixing container 132.

  The additive mixing container 132 is in communication with the dispersion medium mixing container 122 of the dispersion medium mixing device 120, and in communication with the additive feeding portion 134, and the dispersion liquid and the additive flowing from the dispersion medium mixing container 122 And an ink composition. The additive mixing container 132 may have a stirring blade 136 for stirring and mixing the loaded dispersion and the additive.

  The additive input portion 134 is configured to open an additive flow path connecting an additive tank for storing the added additive such as a binder resin, an additive flow path connecting the additive tank and the additive mixing container 132, and the additive flow path. And an additive flow path valve which is closed to control the introduction of the additive from the respective additive tank into the additive mixing container 132.

  In the system 200 for producing the ink composition, the determination unit 160 receives the data output from the input unit 140 and the color tone that the metallic gloss layer should have, as in the system 100 for producing the mixed liquid described above. First, the first plurality of metal nanoparticles and the second plurality of metal nanoparticles are determined. After that, the determination unit 160 refers to the information on the correspondence stored in the storage unit 150 to obtain the first plurality of metal nanoparticles that realize the color tone that the metal gloss layer should have or a color tone similar thereto. And the combination of the second plurality of metal nanoparticles. The determination unit 160 outputs the determined combination to the control unit 170.

  Based on the combination of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles determined by the determination unit 160, the control unit 170 may manufacture an ink composition having any composition. Decide. Furthermore, the control unit 170 refers to the information on the metal nanoparticles stored in each of the metal nanoparticle tanks stored in the storage unit 150 to determine which metal nanoparticles are stored in any metal nanoparticle tank. Decide whether to mix in proportions. Furthermore, the control unit 170 controls the amount of the dispersion medium to be introduced from the dispersion medium introduction unit 124 to make the ink composition have a desired viscosity, and the additive introduction unit 134 to provide the ink composition with desired characteristics. Determine the amount of additive to be added from

  Then, the control unit 170 causes a plurality of types of metal nanoparticles to be introduced into the mixing container 112 so that the composition of the ink composition determined above is realized, and mixes the plurality of types of metal nanoparticles that have been introduced. , And mixed solution. Furthermore, the control unit 170 causes the mixed solution to flow from the mixing container 112 to the dispersion medium mixing container 122, and causes the dispersion medium to be charged from the dispersion medium charging unit 124, thereby mixing the circulated liquid mixture with the charged dispersion medium. To a dispersion. Furthermore, the control unit 170 causes the dispersion to flow from the dispersion medium mixing container 122 to the additive mixing container 132, and causes the additive charging unit 134 to charge the additive, and the circulated dispersion and the charged additive Are mixed to form an ink composition.

3. Ink Composition Yet another embodiment of the present invention relates to an ink composition for forming a metallic gloss layer having a sheet resistance of more than 1 × 10 ⁵ Ω / sq.

  The ink composition comprises the first plurality of metal nanoparticles and the second plurality of metal nanoparticles described above, a dispersion, and optionally added additives.

  The first plurality of metal nanoparticles and the second plurality of metal nanoparticles are detected by measuring the ink composition or the ink composition concentrated by partially removing the solvent by ICP-MS and fluorescent X-ray analysis can do.

  The ink composition has color coordinates (u ', v') of 0.19 <u '<0.27 and 0.45 <v' <0 in the CIE 1976 UCS chromaticity diagram (2 ° visual field). It is possible to form a metallic gloss layer within the range of .57.

In addition, the second plurality of metal nanoparticles is a color coordinate (u ′,) in the CIE 1976 UCS chromaticity diagram (2 ° view) in the color tone of the metallic gloss layer imparted by the first plurality of metal nanoparticles. It is preferable that the distance on the v ') be changed to a color tone separated by 0.001 or more and 0.05 or less. The degree to which the color tone is changed is a metallic gloss layer having a sheet resistance of more than 1 × 10 ⁵ Ω / sq, formed using only the first plurality of metal nanoparticles detected as the metal nanoparticles. And the color tone of a metallic gloss layer having a sheet resistance of greater than 1 × 10 ⁵ Ω / sq, formed by using together the first metal nanoparticles and the second metal nanoparticles. can do.

  As described above, the average particle diameter of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles is preferably 3 nm or more and 100 nm or less.

  Also, as described above, from the viewpoint of further widening the color tone that the metallic gloss layer may have, the first plurality of metal nanoparticles and the second plurality of metal nanoparticles are at least a second plurality of metal nano-particles. The average particle size of the particles is preferably 20 nm or more and 75 nm or less, and the average particle sizes of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles are more preferably 20 nm or more and 75 nm or less .

  In addition, as described above, from the viewpoint of changing the color tone of the metallic gloss layer to a warmer color, when the second plurality of metal nanoparticles are silver particles, the average particle diameter of the second plurality of metal nanoparticles Is preferably 20 nm or less and 30 nm or less. On the other hand, from the viewpoint of changing the color tone of the metallic gloss layer to the color tone of the bulk metal, the average particle diameter of the second plurality of metal nanoparticles is preferably 35 nm or more and 75 nm or less.

  Further, as described above, from the viewpoint of largely changing the color tone of the metallic gloss layer from the color tone imparted by the first plurality of metal nanoparticles, the second plurality of metal nanoparticles is the first plurality of metal nanoparticles. The metal nanoparticles preferably have an average particle size different from 15 nm to 55 nm, more preferably 15 nm to 50 nm, still more preferably 15 nm to 45 nm.

  Also, as described above, the second plurality of metal nanoparticles constitute the first plurality of metal nanoparticles when the metal species constituting the metal nanoparticles are different from the first plurality of metal nanoparticles. It is preferable that the second plurality of metal nanoparticles be composed of a metal species that is different from the metal species in the spectrum shape of the absorption wavelength. For example, when the metal species that make up the first plurality of metal nanoparticles are silver, the metal species that make up the second plurality of metal nanoparticles can be copper.

4. Image Forming Method Still another embodiment of the present invention relates to an image forming method including the step of forming a metallic gloss layer using the above-mentioned ink composition.

  The ink composition can be applied onto a substrate and dried to form a metallic gloss layer. The metallic gloss layer may be used alone or in combination with a coloring material layer to form an image-formed product. The ink composition may be applied onto a known intermediate transfer medium and dried to form an intermediate transfer material including a metallic gloss layer, and then transferred to a substrate to form an image-formed material. .

4-1. The base material is not particularly limited, and an absorbent base material (paper base material) including coated paper including art paper, coated paper, lightweight coated paper, fine coated paper, cast paper and the like and non-coated paper (paper base) , Polyester (PE), polyvinyl chloride (PVC), polyethylene (PE), polyurethane (PU), polypropylene (PP), acrylic resin (PA), polycarbonate (PC), polystyrene (PS), acrylonitrile-butadiene-styrene copolymer Non-absorptive substrates (plastic substrates) composed of plastics including polymers (ABS), polyethylene terephthalate (PET) and polybutadiene terephthalate (PBT), and non-absorptive inorganic materials including metals, glass and the like Media can be used.

4-2. Intermediate Transfer Member The intermediate transfer member is not particularly limited, and various plastics, ceramics, glasses and metals, and composite materials thereof can be used.

4-3. Formation of Metallic Gloss Layer The application method of the ink composition is not particularly limited, and the above ink composition may be applied to the surface of a substrate using a roll coater, a spin coater, etc., spray coating, immersion method, screen The ink composition may be applied to the surface of the substrate by a method such as printing, gravure printing, offset printing or the like, or the ink composition may be landed on the surface of the substrate by an inkjet method. Among these, the inkjet method is preferable from the viewpoint of forming a more precise recorded matter.

  When the inkjet method is used, an inkjet ink composition containing the metal nanoparticles adsorbed with the above-mentioned polymer dispersant, a binder resin and a solvent may be discharged from the nozzle of the inkjet head to land on the surface of the substrate.

  After application of the ink composition, the ink composition may be dried. The drying temperature at this time is preferably less than 100 ° C., and more preferably less than 80 ° C., from the viewpoint of suppressing a change in color tone due to welding and sintering of metal nanoparticles.

4-4. Other Layers The metallic luster layer may be formed in contact with a primer layer for further enhancing the adhesion of metal nanoparticles formed on a substrate. In addition, a coloring material layer or a protective layer may be formed on the surface side of the metal gloss layer of the image-formed product. When an intermediate transfer member is used, an adhesive layer may be formed on the surface side of the metallic gloss layer to adhere the substrate and the metallic gloss layer at the time of transfer to the substrate. When an intermediate transfer member is used, a release layer may be formed on the intermediate transfer member side of the metal gloss layer to release the metal gloss layer and the intermediate transfer member at the time of transfer to the substrate. Also,

4-4-1. Primer Layer The primer layer can be a layer formed of a material conventionally used to enhance adhesion to a substrate such as a pigment containing metal nanoparticles. For example, the primer layer contains a fixing resin.

  Although the film thickness of the primer layer is not particularly limited, it is preferably 0.05 μm or more and 100 μm or less from the viewpoint of sufficiently enhancing the adhesion of the metallic gloss layer to the substrate, and is 0.1 μm or more and 50 μm or less Is more preferably 0.5 μm or more and 10 μm or less.

  The resin for fixing may be any resin conventionally used to enhance the adhesion of the pigment containing metal nanoparticles and the like to the substrate, and may be the same resin as the binder resin described above .

  Examples of the fixing resin include (meth) acrylic resin, epoxy resin, polysiloxane resin, maleic acid resin, polyolefin resin, vinyl resin, polyamide resin, polyvinyl pyrrolidone, polyhydroxystyrene, polyvinyl alcohol, nitrocellulose, acetic acid Cellulose, ethyl cellulose, ethylene-vinyl acetate copolymer, urethane resin, polyester resin, alkyd resin and the like are included. These fixing resins may be used alone or in combination of two or more.

The application amount of the fixing resin to the substrate surface is preferably 0.01 g / m ² or more and 100 g / m ² or less, from the viewpoint of sufficiently enhancing the adhesion of the metallic gloss layer to the substrate, more preferably 0.05 g / ^{m 2} or more 50 g / ^{m 2} or less, and further preferably 0.1 g / ^{m 2} or more and 10 g / ^{m 2} or less.

4-4-2. Color Material Layer The above-mentioned color material layer is a layer for further changing the color tone of the image-formed product to develop a specific metallic color.

  The color material layer can be a layer containing a known pigment or dye and a resin for fixing the pigment or dye. The resin for fixing the pigment or the dye can be selected from the same resin as the binder resin contained in the metallic gloss layer and the resin for fixing contained in the primer layer. The coloring material layer may contain these resins singly or in combination of two or more.

4-4-3. Protective Layer The above-mentioned protective layer is a layer that enhances the abrasion resistance and the like of the metallic gloss layer, and suppresses the detachment of the metal nanoparticles from the image-forming material.

  The said protective layer can be made into the layer containing resin similar to resin for fixation which the binder resin which a genus gloss layer contains, and a primer layer. The said protective layer may contain these resin individually by 1 type, and may contain it in combination of 2 or more types.

4-4-4. Adhesive Layer The adhesive layer is a layer that adheres the metallic gloss layer transferred from the intermediate transfer body to the substrate. The said adhesion layer can be made into the layer containing resin which has adhesiveness.

  Examples of the tacky resin include (meth) acrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl acetal resin, polyether resin, polyurethane resin, styrene acrylate resin, polyacrylamide resin, polyamide resin, polystyrene resin, Polyethylene resin, polypropylene resin, polyvinyl pyrrolidone resin and the like are included. These resins having tackiness may be used singly or in combination of two or more.

4-4-5. Release Layer The release layer is a layer that enhances the releasability of the metallic gloss layer from the intermediate transfer member. The release layer can be a layer containing silicone oil, fluorine-based oil, hydrocarbon oil, mineral oil, vegetable oil, polyalkylene glycol, alkylene glycol ether, alkanediol, molten wax and the like.

4-4-6. Formation of Other Layers The primer layer can be formed by applying a resin composition containing the resin contained in the primer layer described above to the surface of the base before the metal gloss layer is formed. After the application of the resin composition, the resin composition may be dried by heating or the like to form a film of the fixing resin. The drying temperature at this time is preferably less than 100.degree.

  Moreover, the said primer layer provides the resin composition containing the photocurable monomer or oligomer which has a photopolymerizable functional group on the base-material surface before the said metallic-gloss layer is formed, and is said by light irradiation. The resin for fixing can be formed into a film. At this time, the resin composition may further contain a known photopolymerization initiator.

  The color material layer and the protective layer can be formed by applying the resin composition containing the above-mentioned resin to be contained in these layers to the surface side of the metallic gloss layer on the surface of the substrate. At this time, the layer formed can be made into a coloring material layer by making the above-mentioned resin composition contain the above-mentioned well-known pigment or dye. After the application of the resin composition, the resin composition may be dried by heating or the like to form a film of the fixing resin. The drying temperature at this time is preferably less than 100.degree.

  Further, the color material layer and the protective layer apply a resin composition containing a photocurable monomer or oligomer having a photopolymerizable functional group to the surface side of the metal gloss layer on the surface of the base material, and irradiate light. Thus, the resin to be contained in these layers can be formed into a film. At this time, the resin composition may further contain a known photopolymerization initiator.

  The pressure-sensitive adhesive layer can be formed by applying the resin composition containing the resin contained in the pressure-sensitive adhesive layer described above to the surface layer side of the metallic gloss layer on the surface of the intermediate transfer member.

  The release layer can be formed by applying a composition containing the material contained in the release layer described above to the surface of the intermediate transfer member before the metallic gloss layer is formed.

  The method for applying the material contained in each of the above resin compositions or release layers is not particularly limited, and the above resin composition may be applied to the surface of the substrate using a roll coater, a spin coater, or the like, or spray application, The resin composition may be applied to the surface of the substrate by a method such as immersion, screen printing, gravure printing, offset printing, or the substrate by discharging droplets of the resin composition from a nozzle by an inkjet method. It may be landed on the surface of Among these, the inkjet method is preferable from the viewpoint of forming a more precise recorded matter.

5. Image-Forming Material Yet another embodiment of the present invention relates to an image-forming material comprising a metallic gloss layer having a sheet resistance of more than 1 × 10 ⁵ Ω / sq.

  The image-forming material comprises a metallic gloss layer, and the above-mentioned primer layer, color material layer, protective layer or adhesive layer optionally formed.

The metallic gloss layer is a layer having a sheet resistance of greater than 1 × 10 ⁵ Ω / sq, which includes the first plurality of metal nanoparticles and the second plurality of metal nanoparticles described above.

  The first plurality of metal nanoparticles and the second plurality of metal nanoparticles are dissolved in a known solvent to form a primer layer, a metallic gloss layer after removing a colorant layer or a protective layer, or a known solvent. A dispersion in which components of the metallic gloss layer are dissolved or dispersed can be detected by measurement by ICP-MS and fluorescent X-ray analysis.

  The metallic gloss layer has color coordinates (u ′, v ′) of 0.19 <u ′ <0.27 and 0.45 <v ′ <0 in the CIE 1976 UCS chromaticity diagram (2 ° visual field). It is preferable to be included in the range of .57.

In addition, the second plurality of metal nanoparticles is a color coordinate (u ′,) in the CIE 1976 UCS chromaticity diagram (2 ° view) in the color tone of the metallic gloss layer imparted by the first plurality of metal nanoparticles. It is preferable that the distance on the v ') be changed to a color tone separated by 0.001 or more and 0.05 or less. The degree to which the color tone is changed is a metallic gloss layer having a sheet resistance of more than 1 × 10 ⁵ Ω / sq, formed using only the first plurality of metal nanoparticles detected as the metal nanoparticles. And the color tone of a metallic gloss layer having a sheet resistance of greater than 1 × 10 ⁵ Ω / sq, formed by using together the first metal nanoparticles and the second metal nanoparticles. can do.

  As described above, the average particle diameter of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles is preferably 3 nm or more and 100 nm or less.

  Also, as described above, from the viewpoint of further widening the color tone that the metallic gloss layer may have, the first plurality of metal nanoparticles and the second plurality of metal nanoparticles are at least a second plurality of metal nano-particles. The average particle size of the particles is preferably 20 nm or more and 75 nm or less, and the average particle sizes of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles are more preferably 20 nm or more and 75 nm or less .

  In addition, as described above, from the viewpoint of changing the color tone of the metallic gloss layer to a warmer color, when the second plurality of metal nanoparticles are silver particles, the average particle diameter of the second plurality of metal nanoparticles Is preferably 20 nm or less and 30 nm or less. On the other hand, from the viewpoint of changing the color tone of the metallic gloss layer to the color tone of the bulk metal, the average particle diameter of the second plurality of metal nanoparticles is preferably 35 nm or more and 75 nm or less.

  Further, as described above, from the viewpoint of largely changing the color tone of the metallic gloss layer from the color tone imparted by the first plurality of metal nanoparticles, the second plurality of metal nanoparticles is the first plurality of metal nanoparticles. The metal nanoparticles preferably have an average particle size different from 15 nm to 55 nm, more preferably 15 nm to 50 nm, still more preferably 15 nm to 45 nm.

  Also, as described above, the second plurality of metal nanoparticles constitute the first plurality of metal nanoparticles when the metal species constituting the metal nanoparticles are different from the first plurality of metal nanoparticles. It is preferable that the second plurality of metal nanoparticles be composed of a metal species that is different from the metal species in the spectrum shape of the absorption wavelength. For example, when the metal species that make up the first plurality of metal nanoparticles are silver, the metal species that make up the second plurality of metal nanoparticles can be copper.

  Hereinafter, specific examples of the present invention will be described together with comparative examples, but the present invention is not limited thereto.

1. Material 1-1. Preparation of Metal Nanoparticles <Silver Nanoparticle Dispersion 1 (Ag-1)>
In a 1-L separable flask with a flat stirring blade and a baffle, 8.6 g of DISPERBYK-190 (by BIC-Chemie, “DISPERBYK” is a registered trademark of the company), and 269 g of ion-exchanged water Stir and dissolve DISPERBYK-190. Subsequently, 55 g of silver nitrate dissolved in 269 g of ion-exchanged water was charged into the separable flask while stirring. After further adding 70 g of aqueous ammonia and stirring, the above separable flask was placed in a water bath, and heated and stirred until the temperature of the solution stabilized at 80 ° C. Thereafter, 144 g of dimethylaminoethanol was added to the separable flask, and stirring was further performed while maintaining the temperature at 80 ° C. for 6 hours to obtain a reaction solution containing silver nanoparticles.

  The obtained reaction solution was placed in a stainless steel cup, and 2 L of ion exchanged water was further added, and then the pump was operated to perform ultrafiltration. When the solution in the stainless steel cup decreased, ion-exchanged water was again added, and purification was repeated until the conductivity of the filtrate became 100 μS / cm or less. Thereafter, the filtrate was concentrated to obtain a silver nanoparticle dispersion 1 (Ag-1) with a solid content of 30 wt%.

  In addition, the ultrafiltration device is a Asahi Kasei Co., Ltd. ultrafiltration module AHP1010 (fractional molecular weight: 50000, number of membranes used: 400), and a tube pump made by Masterflex Co., Ltd., connected by Tygon Tube It was used.

The obtained silver nanoparticle dispersion was observed by SEM, and the volume particle size distribution was determined according to the following procedure.
1) A silver nanoparticle dispersion was applied on a glass plate and vacuum deaerated to volatilize solvent components to obtain a sample. The sample obtained was observed using SEM (JEOL JSM-7401F, manufactured by Nippon Denshi Co., Ltd.), and the particle diameter of any 300 silver nanoparticles was measured.
2) Based on the obtained measurement data, a particle size distribution based on volume is determined using image processing software Image J, and D50 (median diameter) thereof is defined as an average particle diameter (volume average particle diameter) in terms of volume. In addition, the number of peaks and the full width at half maximum were determined from the particle size distribution of silver nanoparticles.

  In addition, since the dispersing agent adsorbed on the surface of the silver nanoparticles can not be observed by SEM, the particle diameter of the silver nanoparticles was determined as the particle diameter of silver nano particles not containing the dispersing agent.

  The average particle diameter of the silver nanoparticle dispersion liquid 1 was 25 nm, the volume particle size distribution was unimodal, and the full width at half maximum was 21 nm.

<Silver nanoparticle dispersion 2 (Ag-2)>
In the preparation of silver nanoparticle dispersion 1, silver nanoparticle dispersion 2 (CO 2 dispersion 2 Ag-2) was obtained.

  The average particle size, the number of peaks, and the full width at half maximum of the silver nanoparticle dispersion liquid 2 were determined in the same manner as the silver nanoparticle dispersion liquid 1. The average particle diameter of the silver nanoparticle dispersion 2 was 40 nm, the volume particle size distribution was unimodal, and the full width at half maximum was 23 nm.

<Silver nanoparticle dispersion 3 (Ag-3)>
In the preparation of silver nanoparticle dispersion 1, silver nanoparticle dispersion 3 (a) was prepared in the same manner except that the amount of silver nitrate added was 80 g, the dispersant was 7.2 g, the amount of aqueous ammonia was 102 g, and the amount of dimethylaminoethanol was 209 g. Ag-3) was obtained.

  The average particle size, the number of peaks, and the full width at half maximum of the silver nanoparticle dispersion liquid 3 were determined in the same manner as the silver nanoparticle dispersion liquid 1. The average particle diameter of the silver nanoparticle dispersion liquid 3 was 70 nm, the volume particle size distribution was unimodal, and the full width at half maximum was 20 nm.

<Silver nanoparticle dispersion 4 (Ag-4)>
The silver nanoparticle dispersion 4A was prepared in the same manner as in the preparation of the silver nanoparticle dispersion 1, except that the amount of silver nitrate added was 5 g, the dispersant was 2.0 g, the amount of aqueous ammonia was 10 g, and the amount of dimethylaminoethanol was 8 g. Obtained.

  The average particle size, the number of peaks, and the full width at half maximum of silver nanoparticle dispersion liquid 4A were determined in the same manner as in silver nanoparticle dispersion liquid 1 above. The average particle diameter of the silver nanoparticle dispersion 4A was 20 nm, the volume particle size distribution was unimodal, and the half width was 3 nm.

  8.0 g of DISPERBYK-190 and 269 g of ion-exchanged water were charged into a 1 L separable flask having a flat stirring blade and a baffle and stirred to dissolve DISPERBYK-190. Subsequently, 5 g of the prepared silver nanoparticle dispersion liquid 4A (30 wt%) was added, and then, 48 g of silver nitrate dissolved in 269 g of ion exchanged water was charged into the separable flask while stirring. Further, 80 g of ammonia water was added and stirring was carried out, and then the above separable flask was put into a water bath, and heated and stirred until the temperature of the solution stabilized at 80 ° C. Thereafter, 75 g of dimethylaminoethanol was added to the separable flask, and stirring was further continued for 9 hours while maintaining the temperature at 80 ° C., to obtain a reaction solution containing silver nanoparticles.

  The obtained reaction solution was placed in a stainless steel cup, and 2 L of ion exchanged water was further added, and then the pump was operated to perform ultrafiltration. When the solution in the stainless steel cup decreased, ion-exchanged water was again added, and purification was repeated until the conductivity of the filtrate became 100 μS / cm or less. Thereafter, the filtrate was concentrated to obtain a silver nanoparticle dispersion 4 (Ag-4) with a solid content of 30 wt%.

  The ultrafiltration apparatus used was an ultrafiltration module AHP1010 (Asahi Kasei Co., Ltd., molecular weight cut off: 50000, number of membranes used: 400), and a tube pump (Masterflex Co., Ltd.) connected by a tygon tube. .

  The average particle size, the number of peaks, and the full width at half maximum of the silver nanoparticle dispersion liquid 4 were determined in the same manner as the silver nanoparticle dispersion liquid 1. The average particle diameter of the silver nanoparticle dispersion 4 was 55 nm, the volume particle size distribution was unimodal, and the full width at half maximum was 4 nm.

<Silver nanoparticle dispersion 5 (Ag-5)>
A silver nanoparticle dispersion 5 (Ag-5) was obtained in the same manner as in the preparation of the silver nanoparticle dispersion 2, except that 80 g of ion-exchanged water was used instead of ammonia water.

  The average particle size, the number of peaks, and the full width at half maximum of the silver nanoparticle dispersion liquid 2 were determined in the same manner as the silver nanoparticle dispersion liquid 1. The average particle diameter of the silver nanoparticle dispersion 2 was 42 nm, the volume particle size distribution was unimodal, and the full width at half maximum was 35 nm.

<Copper nanoparticle dispersion 1 (Cu-1)>
In preparation of silver nanoparticle dispersion 1, 117 g of copper sulfate pentahydrate was replaced with silver nitrate, 7.2 g of dispersant, 102 g of aqueous ammonia, 102 g of aqueous ammonia, and 780 mL of 3 M aqueous sodium ascorbate solution instead of dimethylaminoethanol. Copper nanoparticle dispersion liquid 1 (Cu-1) was obtained in the same manner except that the reaction was carried out under a nitrogen atmosphere.

  The average particle size, the number of peaks, and the full width at half maximum of the copper nanoparticle dispersion liquid 1 were determined in the same manner as the silver nanoparticle dispersion liquid 1 above. The average particle size of the copper nanoparticle dispersion 1 was 50 nm, the volume particle size distribution was unimodal, and the full width at half maximum was 20 nm.

1-2. Preparation of mixed solution <mixed solution 1>
Silver nanoparticle dispersion 1 to silver nanoparticle dispersion 5 and copper nanoparticle dispersion 1 are mixed at a ratio described in Table 1 to prepare mixed solution 1 to mixed solution 3 and mixed solution 5 to mixed solution 7 did. Moreover, the silver nanoparticle dispersion liquid 1-the silver nanoparticle dispersion liquid 5 were used as it was, and it was set as the liquid mixture 8-the liquid mixture 12. In addition, the copper nanoparticle dispersion liquid 1 was used as it was to be a liquid mixture 4. In addition, the numerical value described in the column of "volume fraction" of Table 1 mixed the dispersion liquid in the ratio in which the volume fraction of metal nanoparticles contained in the mixed solution becomes the numerical value described in this column. Indicates that.

1-3. Preparation of Resin Particle Dispersion <Resin Particle Dispersion 1>
10 parts by mass of terephthalic acid as an acid component, 190 parts by mass of isophthalic acid and 170 parts by mass of adipic acid, and 32 parts by mass of ethylene glycol as a glycol component and 510 parts by mass of neopentyl glycol in a flask equipped with a dehydrator And 0.2 parts by mass of tetraisopropyl titanate as a reaction catalyst, followed by condensation reaction at 220 ° C. until the acid value becomes 1.0 or less, and the moisture becomes 0.05% or less, to obtain polyester glycol 1 .

  In a four-necked flask equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen blowing pipe, 488 parts by mass of polyester glycol 1 obtained above, 13 parts by mass of trimethylolpropane, and 88 parts by mass of dimethylol propionic acid 252 parts by mass of isophorone diisocyanate and 670 parts by mass of methyl ethyl ketone were added and reacted at 75 ° C. for 4 hours to obtain a methyl ethyl ketone solution of a urethane prepolymer. The solution was cooled to 40 ° C., and 40 parts by mass of triethylamine was added thereto for neutralization. Thereafter, 1850 parts by mass of ion exchange water was gradually added, and the mixture was emulsified and dispersed using a homogenizer, and stirred for 1 hour. The solvent was removed at 50 ° C. under reduced pressure, and ion-exchanged water was further added to obtain a resin particle dispersion 1 in which a urethane resin emulsion having a solid content concentration of about 20% was dispersed. It was 40 nm when the average particle diameter of the obtained resin particle was measured similarly to the said silver nanoparticle dispersion liquid 1. FIG.

1-4. Solvent H ₂ O: Water PG: Propylene glycol (boiling point: 188 ° C)
TEGME: Triethylene glycol monomethyl ether (boiling point: 248 ° C)

1-4. Additives Surfactant: BYK-348 manufactured by Big Chemie ("BYK" is a registered trademark of the company)

2. Preparation of Ink Composition After mixing any one of mixture 1 to mixture 12, emulsion resin particle dispersion 1, PG, TEGME, BYK-348 and H ₂ O in the following proportions, ADVATEC Teflon (“ "Teflon" was filtered through a DuPont (registered trademark) 3 μm membrane filter to prepare ink composition 1 to ink composition 12. The amount of the mixed solution indicates that the amount of metal nanoparticles in the ink composition has added the following value, and the amount of the emulsion resin particle dispersion is determined by adding resin particles (solids in the ink composition) It shows that the amount of minutes has added the quantity which becomes the following value.
Mixture: 5.0% by mass
Resin particle dispersion 1: 2.0% by mass
PG: 10.0 mass%
TEGME: 25.4 mass%
BYK-348: 0.1 mass%
H ₂ O: Remainder

3. Evaluation of Metallic Gloss Layer The metallic gloss layer 1 to the metallic gloss layer 9 were formed on the following substrates using the ink composition 1 to the ink composition 12 under the following conditions.

(Base material)
Coated paper: WRG3-36 (manufactured by Lamy Corporation)

(Formation conditions of metallic gloss layer)
A metallic gloss layer was formed on each of the substrates using an inkjet recording apparatus having a piezoelectric inkjet nozzle. The inkjet recording apparatus includes an ink tank, an ink supply pipe, an ink supply tank immediately before the inkjet head, a filter, and a piezoelectric inkjet head in this order from the upstream side to the downstream side through which ink flows. . The ink jet head was driven under the condition that the droplet volume was 14 pl, the printing speed was 0.5 m / sec, the ejection frequency was 10.5 kHz, and the printing rate was 100%, and the ink droplets were ejected and landed on each substrate . After landing, it was dried at 60 ° C. for about 10 minutes to obtain a metallic gloss layer.

  The color coordinates and sheet resistance of the obtained metallic gloss layer were evaluated by the following method.

3-1. Color Coordinates The color coordinates of the metallic gloss layer were evaluated by the method described in JIS Z 8781-5, and were used as the measured color coordinates.

  Furthermore, the optical spectrum is simulated by the FDTD method from the particle size distribution and the optical constant of the metal nanoparticles contained in each ink composition, and the optical constant of the resin contained in the resin particle dispersion, and the simulated optical spectrum is JIS Z The color coordinates obtained by the method described in 8781-5 were used as the estimated color coordinates.

3-2. Change in color tone The metallic gloss layer formed using Ink Composition 1, Ink Composition 2, Ink Composition 4 to Ink Composition 6, and using only the first plurality of metal nanoparticles contained in the ink composition Colors in the IE 1976 UCS chromaticity diagram (2 ° visual field) with the metallic gloss layer (ink composition 3 and metallic gloss layer formed using any of ink composition 7 to ink composition 10) The distance on the coordinates (u ', v') ((absolute value of difference of values of u ') ² + (absolute value of difference of values of v') ² square root) was determined.

3-3. Sheet resistance A sheet resistance was obtained by measurement using a measuring probe of PSP type using a volume resistivity measuring device Lorester manufactured by Mitsubishi Chemical Co., Ltd. and a four-terminal method. The above resistance indicator is 1.0 × ^{10 6.0} Ω / sq was measurement limit.

  The evaluation results are shown in Table 2.

  Metallic gloss layer No. No. 1 to No. 1 metallic gloss layer 3, metallic gloss layer No. No. 5 metallic gloss layer No. As shown in 7, changing the color tone of the formed metallic gloss layer by preparing a ink composition by mixing a plurality of metal nanoparticles different in particle size distribution or metal species constituting the metal nanoparticles. did it.

  According to the present invention, a metallic gloss layer having a wider color gamut can be formed while exhibiting metallic gloss. Therefore, the present invention is expected to expand the range of application of the recorded matter having the luminosity, and to contribute to the development and spread of the technology in the field.

DESCRIPTION OF SYMBOLS 100 System to manufacture mixed solution 110 Mixing apparatus 112 Mixing container 114a, 114b, 114c Metal nanoparticle input part 116 Stirring blade 120 Dispersion medium mixing apparatus 122 Dispersion medium mixing container 124 Dispersion medium input part 126 Stirring blade 130 Additive mixing apparatus 132 Additive mixing container 134 Additive feeding portion 136 Stirring blade 140 Input portion 150 Storage portion 160 Determination portion 170 Control portion 200 System for producing ink composition

Claims (19)

A method of producing a mixture,
The first plurality of metal nanoparticles imparting a main color tone to the metallic gloss layer when the mixture liquid is used as an ink composition to form a metallic gloss layer having a sheet resistance of greater than 1 × 10 ⁵ Ω / sq. When,
The first plurality of metal nanoparticles are a plurality of metal nanoparticles different in particle size distribution or metal species constituting the metal nanoparticles, and are applied to the metallic gloss layer by the first plurality of metal nanoparticles Mixing the second plurality of metal nanoparticles to change the color tone,
Method. A combination of metal nanoparticles different in particle size distribution or different metal species constituting the metal nanoparticles, and a color tone of a metallic gloss layer having a sheet resistance realized by the combination of more than 1 × 10 ⁵ Ω / sq, obtained in advance. Refer to the correspondence between and,
The method according to claim 1, further comprising the step of determining the combination of the first plurality of metal particles and the second plurality of metal particles to achieve the specific color tone, prior to the mixing step. Method.   The second plurality of metal nanoparticles have a color tone (u ′,) in the CIE 1976 UCS chromaticity diagram (2 ° visual field), which is a color tone imparted to the metallic gloss layer by the first plurality of metal nanoparticles. The method according to claim 1, wherein v ′) is changed to a color tone separated by a distance of 0.001 or more and 0.05 or less.   The first plurality of metal nanoparticles and the second plurality of metal nanoparticles are all metal nanoparticles having a volume average particle diameter of 20 nm or more and 75 nm or less. The method described in.   5. The metal nanoparticles according to any one of claims 1 to 4, wherein the first plurality of metal nanoparticles or the second plurality of metal nanoparticles are those that receive surface electromagnetic waves to generate surface plasmon resonance. The method described in.   The first plurality of metal nanoparticles and the second plurality of metal nanoparticles are metal nanoparticles having the same metal species constituting a metal nanoparticle and having a volume average particle diameter different from each other by 15 nm or more. The method according to any one of 1 to 5.   The metal nanoparticles according to any one of claims 1 to 5, wherein the first plurality of metal nanoparticles and the second plurality of metal nanoparticles are metal nanoparticles different in metal species constituting the metal nanoparticles. Method. The first plurality of metal nanoparticles are a plurality of silver nanoparticles,
The second plurality of metal nanoparticles are a plurality of copper nanoparticles,
A method according to any one of the preceding claims. A system for producing a liquid mixture,
With a mixing vessel,
The first plurality of metal nanoparticles imparting a main color tone to the metallic gloss layer when the mixture liquid is used as an ink composition to form a metallic gloss layer having a sheet resistance of greater than 1 × 10 ⁵ Ω / sq. A first charging unit for charging the mixing container into the mixing container;
The first plurality of metal nanoparticles are a plurality of metal nanoparticles different in particle size distribution or metal species constituting the metal nanoparticles, and are applied to the metallic gloss layer by the first plurality of metal nanoparticles A second charging unit for charging a second plurality of metal nanoparticles for changing the color tone to the mixing container;
With a system. A combination of metal nanoparticles different in particle size distribution or different metal species constituting the metal nanoparticles, and a color tone of a metallic gloss layer having a sheet resistance realized by the combination of more than 1 × 10 ⁵ Ω / sq, obtained in advance. Refer to the correspondence between and,
The system according to claim 9, further comprising: a determination unit that determines a combination of the first plurality of metal particles and the second plurality of metal particles to achieve the particular color tone.   The determining unit determines the color of the color tone in the CIE 1976 UCS chromaticity diagram (2 ° view) in which the second plurality of metal nanoparticles are imparted to the metal gloss layer by the first plurality of metal nanoparticles. The system according to claim 10, wherein the combination is determined with reference to the correspondence relationship in which the distance on the coordinates (u ', v') changes to a color tone separated by 0.001 or more and 0.05 or less.   In the correspondence relationship, the determination unit includes a combination in which each of the first plurality of metal nanoparticles and the second plurality of metal nanoparticles is a metal nanoparticle having a volume average particle diameter of 20 nm or more and 75 nm or less. The system according to claim 10 or 11, wherein the combination is determined with reference to.   The correspondence relationship, wherein the determination unit includes a combination in which the first plurality of metal nanoparticles or the second plurality of metal nanoparticles are metal nanoparticles that receive surface electromagnetic waves to generate surface plasmon resonance. The system according to any one of claims 10 to 12, wherein the combination is determined with reference to.   The determination unit is a metal nanoparticle in which the first plurality of metal nanoparticles and the second plurality of metal nanoparticles differ in volume average particle diameter from each other by 15 nm or more, and the metal species constituting the metal nanoparticle are the same. The system according to any one of claims 10 to 13, wherein the combination is determined with reference to the correspondence including a combination of   The determination unit refers to the correspondence relationship including a combination in which the first plurality of metal nanoparticles and the second plurality of metal nanoparticles are metal nanoparticles different in metal species constituting the metal nanoparticles. The system according to any one of claims 10 to 13, wherein the combination is determined.   The determination unit refers to the correspondence including a combination in which the first plurality of metal nanoparticles are a plurality of silver nanoparticles, and the second plurality of metal nanoparticles are a plurality of copper nanoparticles. The system according to any one of claims 10-15, wherein the combination is determined. An ink composition for forming a metallic gloss layer having a sheet resistance of greater than 1 × 10 ⁵ Ω / sq,
A plurality of first metal nanoparticles that impart a main color tone to the metallic gloss layer;
The first plurality of metal nanoparticles are a plurality of metal nanoparticles different in particle size distribution or metal species constituting the metal nanoparticles, and are applied to the metallic gloss layer by the first plurality of metal nanoparticles And a second plurality of metal nanoparticles for changing the color tone,
Ink composition.   An image forming method comprising the steps of applying the ink composition according to claim 17 onto a substrate and drying it to form a metallic gloss layer. An image formation comprising a metallic gloss layer having a sheet resistance of more than 1 × 10 ⁵ Ω / sq,
The metallic gloss layer is
A plurality of first metal nanoparticles that impart a main color tone to the metallic gloss layer;
The first plurality of metal nanoparticles are a plurality of metal nanoparticles different in particle size distribution or metal species constituting the metal nanoparticles, and are applied to the metallic gloss layer by the first plurality of metal nanoparticles And a second plurality of metal nanoparticles for changing the color tone,
Image formation.

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