Colored resin particles and light-adjusting laminate

Abstract

This invention provides colored resin particles that can precisely control the gap between substrates and suppress light leakage. The colored resin particles of this invention comprise resin particles and a colorant. When measuring the luminance of the colored resin particles before light irradiation and after light irradiation with a cumulative light intensity of 540 MJ / m² according to the L*a*b* colorimetric system of JIS Z8781-4:2013, the luminance L0* of the colored resin particles before light irradiation is 0 to 60, and the ratio of the luminance L0* of the colored resin particles before light irradiation to the luminance L540* of the colored resin particles after light irradiation is 0.3 or higher.

Description

Technical Field

[0001] The present invention relates to a colored resin particle and a light-adjusting laminate using the above-mentioned colored resin particle. Prior Technology

[0002] Dimming materials, such as dimming glass or dimming films, are materials whose transmittance changes depending on the presence or absence of an applied electric field, and whose incident light amount can be adjusted. Furthermore, based on the mechanism by which the transmittance changes, dimming materials are broadly classified into SPD (Suspended Particle Device) and PDLC (Polymer Dispersed Liquid Crystal) types.

[0003] SPD (Spectrum Dimming and Propagation) is a method of dispersing a light-modifying suspension within a resin matrix. The light-modifying suspension contains light-modifying particles. These particles are responsive to an electric field. In SPD, without an applied electric field, the light-modifying particles dispersed in the suspension absorb, scatter, or reflect light due to Brownian motion, thus preventing incident light from passing through the dimming material. When an electric field is applied, the light-modifying particles become polarized and align in a direction parallel to the electric field, allowing incident light to pass through the dimming material. Thus, SPD adjusts light transmittance by utilizing the polarization and alignment of the light-modifying particles.

[0004] PDLC (Potentially Activated Liquid Crystal Lithography) is a method of dispersing liquid crystals within a resin matrix. PDLC can be categorized into two types: dispersing the liquid crystal and resin matrix as a continuous phase, and dispersing the liquid crystal in the form of liquid crystal capsules within the resin matrix. In the absence of an applied electric field, the liquid crystal molecules are not uniformly aligned, resulting in a difference in refractive index between the resin matrix and the liquid crystal. This causes incident light to be scattered within the light-sensing material, resulting in an opaque appearance. When an electric field is applied, the liquid crystal molecules align in a direction parallel to the electric field. At this point, the refractive index of the resin matrix and the refractive index of the liquid crystal become equal, allowing incident light to pass through the light-sensing material, resulting in a transparent appearance. Thus, PDLC adjusts light transmittance by utilizing the molecular alignment of the liquid crystal.

[0005] When fabricating a dimming laminate using dimming materials, spacers are sometimes used to control the gap between two substrates. Examples of such spacers include resin particles. As one example of such resin particles, Patent Document 1 discloses a type of microparticle (resin particle) containing cross-linked polymer material coated with a fluorinated resin or a silicone resin. [Previous Technical Documents] [Patent Literature]

[0006] [Patent Document 1] Japanese Patent Publication No. Kaihei 10-010540 Summary of the Invention

[0007] [The problem the invention aims to solve]

[0008] When resin particles, as described in Patent Document 1, are used as spacers, light can sometimes pass through the resin particles, resulting in light leakage. This light leakage phenomenon can lead to a decrease in display quality, such as reduced contrast or white spots.

[0009] The purpose of this invention is to provide a colored resin particle that can precisely control the gap between substrates and suppress light leakage. Furthermore, the purpose of this invention is to provide a light-modulating laminate that can precisely control the gap between substrates and suppress light leakage. [Technical means to solve the problem]

[0010] According to a broader embodiment of the present invention, a coloring resin particle is provided, comprising resin particles and a coloring agent. When the brightness of the coloring resin particle before light irradiation and the coloring resin particle after light irradiation with a cumulative light intensity of 540 MJ / m² are measured according to the L*a*b* colorimetric system of JIS Z8781-4:2013, the brightness L0* of the coloring resin particle before light irradiation is 0 to 60, and the ratio of the brightness L0* of the coloring resin particle before light irradiation to the brightness L540* of the coloring resin particle after light irradiation is 0.3 or higher.

[0011] In a specific state of the colored resin particles of the present invention, the 20% K value is 100 N / mm² or more and 5000 N / mm² or less.

[0012] In a specific state of the colored resin particles of the present invention, the volume resistivity is 1.0 × 10⁹ Ω·cm or higher.

[0013] In a specific state sample of the colored resin particles of the present invention, the average particle size is 1 μm or more and 150 μm or less.

[0014] In a specific state of the colored resin particles of the present invention, there are no particles having a particle size of more than 1.2 times the average particle size, or there are particles having a particle size of more than 1.2 times the average particle size of less than 1000 ppm.

[0015] In a specific state sample of the colored resin particles of the present invention, the particle size CV value is less than 10%.

[0016] In a specific state of the colored resin particles of the present invention, the colorant comprises organic black pigment, titanium black particles, or carbon black particles.

[0017] In a specific state of the colored resin particles of the present invention, the colored resin particles contain the above-mentioned colorant in an amount of less than 20% by weight out of 100% by weight of the colored resin particles.

[0018] In a specific state of the colored resin particles of the present invention, the specific gravity is 1.5 or less.

[0019] In a specific state of the colored resin particles of the present invention, the colored resin particles contain components derived from polyfunctional (meth)acrylate compounds.

[0020] In a specific state of the colored resin particles of the present invention, the colored resin particles contain components derived from polyfunctional (meth)acrylate compounds in an amount of 50% or more of 100% by weight of the colored resin particles.

[0021] In a specific state of the colored resin particles of the present invention, the aforementioned colored resin particles can be used as spacers.

[0022] In a specific state of the colored resin particles of the present invention, the aforementioned colored resin particles can be used as spacers in a light-adjusting laminate.

[0023] According to a broader aspect of the present invention, a dimming laminate is provided, comprising a first substrate, a second substrate, and a dimming layer disposed between the first substrate and the second substrate, the dimming layer comprising the aforementioned colored resin particles. [Effects of the Invention]

[0024] The coloring resin particles of this invention comprise resin particles and a coloring agent. Regarding the coloring resin particles of this invention, when measuring the luminance according to the L*a*b* colorimetric system of JIS Z8781-4:2013 for both the coloring resin particles before light irradiation and the coloring resin particles after light irradiation with a cumulative light intensity of 540 MJ / m², the luminance L0* of the coloring resin particles before light irradiation is 0 to 60. In the above measurements, the ratio of the luminance L0* of the coloring resin particles before light irradiation to the luminance L540* of the coloring resin particles after light irradiation is 0.3 or higher. Because the coloring resin particles of this invention have the above-described structure, the gap between substrates can be controlled with high precision, and light leakage can be suppressed. Simple Explanation of the Diagram

[0025] Figure 1 is a schematic cross-sectional view of the colored resin particles according to the first embodiment of the present invention. Figure 2 is a schematic cross-sectional view of a PDLC-type light-adjusting laminate containing the colored resin particles of the first embodiment of the present invention. Figure 3 is a schematic cross-sectional view of a light-adjusting laminate containing the colored resin particles of the first embodiment of the present invention in an SPD manner. Implementation

[0026] The present invention will now be described in detail. Furthermore, in this specification, for example, "(meth)acrylate" means one or both of "acrylate" and "methacrylate", and "(meth)acrylate group" means one or both of "acrylate group" and "methacrylate group".

[0027] (Colored resin particles) The coloring resin particles of this invention comprise resin particles and a coloring agent. Regarding the coloring resin particles of this invention, when measuring the luminance of the coloring resin particles before light irradiation and after light irradiation with a cumulative light intensity of 540 MJ / m² according to the L*a*b* colorimetric system of JIS Z8781-4:2013, the luminance L0* of the coloring resin particles before light irradiation is 0 to 60. In the above measurements, the ratio of the luminance L0* of the coloring resin particles before light irradiation to the luminance L540* of the coloring resin particles after light irradiation is 0.3 or higher.

[0028] Because the colored resin particles of the present invention have the above-described structure, the gap between the substrates can be controlled with high precision, and light leakage can be suppressed.

[0029] Furthermore, previously colored particles that have been dyed may sometimes fade due to prolonged exposure, resulting in reduced light-blocking properties and light leakage. On the other hand, the colored resin particles of the present invention, having the above-described structure, can suppress light leakage for a long time even with prolonged exposure.

[0030] From the viewpoint of further effectively suppressing light leakage, in the above-mentioned measurements, the brightness L0* of the above-mentioned colored resin particles before light irradiation is preferably 1 or more, more preferably 3 or more, more preferably 55 or less, more preferably 40 or less, and even more preferably 30 or less.

[0031] From the viewpoint of further effectively suppressing light leakage, in the above-mentioned measurement, the brightness L 540* of the above-mentioned colored resin particles after light irradiation is preferably 1 or more, more preferably 3 or more, and even more preferably 4 or more, and preferably 60 or less, more preferably 50 or less, and even more preferably 40 or less.

[0032] From the viewpoint of further effectively suppressing light leakage, in the above-mentioned measurements, the ratio (L0* / L540*) of the brightness L0* of the aforementioned colored resin particles before light irradiation to the brightness L540* of the aforementioned colored resin particles after light irradiation is preferably 0.4 or more, more preferably 0.5 or more, further preferably 0.6 or more, and particularly preferably 0.8 or more. There is no particular limitation on the upper limit of the above ratio (L0* / L540*). The above ratio (L0* / L540*) may also be 1.0 or less.

[0033] The luminance L0* of the aforementioned colored resin particles before light irradiation and the luminance L540* of the aforementioned colored resin particles after light irradiation can be measured as follows: Prepare a plate-shaped sample with the same composition as the colored resin particles. Irradiate the plate-shaped sample with light at an illuminance of 255 W / m² for 588 hours (cumulative light intensity: 540 MJ / m²). For any 10 points on the sample before and after light irradiation, use a colorimeter, setting the measurement range to a circle with a diameter of 8 mm, to measure the luminance. The average values ​​are taken as luminance L0* and luminance L540*. Examples of such colorimeters include the "TES-3250" manufactured by SATOTECH.

[0034] Furthermore, the brightness L0* of the aforementioned colored resin particles before light irradiation and the brightness L540* of the aforementioned colored resin particles after light irradiation can be measured for each colored resin particle. The colored resin particles before and after light irradiation are mounted on an adhesive tape, and the brightness is measured at any 10 points on the colored resin particles using a colorimeter, with the measurement range set as a circle with a diameter of 8 mm. The average values ​​are taken as the brightness L0* and brightness L540*. Examples of such colorimeters include the "TES-3250" manufactured by SATOTECH. Furthermore, the brightness of the aforementioned colored resin particles after light irradiation can be obtained by irradiating the colored resin particles with a daylight-type carbon arc lamp at an illuminance of 255 W / m² for 588 hours (cumulative light intensity: 540 MJ / m²). Furthermore, the aforementioned colored resin particles after light irradiation can be obtained by irradiating the colored resin particles with a super xenon lamp at an illuminance of 180 W / m² for 830 hours (cumulative light intensity: 540 MJ / m²). Alternatively, the aforementioned colored resin particles after light irradiation can also be obtained by irradiating the colored resin particles with a xenon lamp at an illuminance of 60 W / m² for 2500 hours (cumulative light intensity: 540 MJ / m²).

[0035] As a method to easily control the brightness L0* of the above-mentioned colored resin particles before light irradiation and the brightness L540* of the above-mentioned colored resin particles after light irradiation within a suitable range, methods such as adjusting the type and content of the above-mentioned colorant can be cited as examples.

[0036] From the viewpoint of further effectively suppressing light leakage, the visible light transmittance of the aforementioned colored resin particles is preferably 40% or less, more preferably 20% or less, and even more preferably 10% or less.

[0037] The visible light transmittance of the aforementioned colored resin particles can be measured in the following ways: A plate-shaped sample with the same composition as the colored resin particles is prepared, and spectrophotometric measurements are performed. The visible light transmittance can be measured according to ISO 13837:2008. Alternatively, it can be measured according to the method of JIS K6714 standard.

[0038] The volume resistivity of the aforementioned colored resin particles is preferably 1.0 × 10⁹ Ω·cm or higher, more preferably 1.0 × 10¹⁰ Ω·cm or higher, further preferably 1.0 × 10¹¹ Ω·cm or higher, and even more preferably 1.0 × 10¹² Ω·cm or higher. If the volume resistivity of the aforementioned colored resin particles is above the lower limit, the insulation reliability of the aforementioned colored resin particles can be improved, and as a result, the conduction reliability of the obtained dimming laminate can be improved. There is no particular limitation on the upper limit of the volume resistivity of the aforementioned colored resin particles. The volume resistivity of the aforementioned colored resin particles can also be 1.0 × 10²⁰ Ω·cm or lower, or 1.0 × 10¹⁸ Ω·cm or lower.

[0039] The volume resistivity of the aforementioned colored resin particles can be measured as follows: Using a powder resistivity measuring system (e.g., the MCP-PD51 powder resistivity measuring system manufactured by Mitsubishi Chemical Analytech), a load is applied to the colored resin particles filled in the probe using a hydraulic pump at a range of 4 kN from 0 kN to 20 kN. The volume resistivity is measured for the colored resin particles under various loads (0 kN, 4 kN, 8 kN, 12 kN, 16 kN, and 20 kN), and the lowest value is taken as the volume resistivity of the colored resin particles.

[0040] The 20% K value of the aforementioned coloring resin particles is preferably 100 N / mm² or higher, more preferably 700 N / mm² or higher, even more preferably 1000 N / mm² or higher, and preferably 5000 N / mm² or lower, even more preferably 4000 N / mm² or lower, and even more preferably 3000 N / mm² or lower. If the 20% K value of the aforementioned coloring resin particles is above the lower limit and below the upper limit, the gap between the substrates can be controlled with even higher precision, preventing damage to the substrates. Furthermore, if the 20% K value of the aforementioned coloring resin particles is above the lower limit and below the upper limit, the destruction of the coloring resin particles can be suppressed, thus suppressing the outflow of the colorant from the coloring resin particles and preventing short circuits. As a result, the conductivity reliability of the obtained dimming laminate can be improved.

[0041] The 20% K value of the aforementioned colored resin particles can be determined as follows: Using a micro compression tester, the colored resin particles are compressed under a maximum test load of 20 mN at 25°C for 60 seconds using the smooth end face of a cylindrical (50 μm diameter, made of diamond) indenter. The load value (N) and compression displacement (mm) are measured. Based on the obtained measured values, the 20% K value can be calculated using the following formula. For example, a Fischerscope H-100 manufactured by Fischer Corporation can be used as the micro compression tester.

[0042] 20%K value (N / mm 2)=(3 / 2 1 / 2)·F·S -3 / 2·R -1 / 2 F: Load value (N) when the colored resin particles undergo 20% compression deformation. S: Compression displacement (mm) of the colored resin particles when they undergo 20% compression deformation. R: Radius of the colored resin particles (mm)

[0043] As a method to easily control the 20% K value of the above-mentioned colored resin particles within a suitable range, examples include: adjusting the number of polymeric functional groups and molecular weight of the material (polymeric monomer) used to form the above-mentioned resin particles, or adjusting the type and content of the above-mentioned colorant, thereby adjusting the crosslinking density of the above-mentioned colored resin particles, etc.

[0044] Furthermore, since the aforementioned colored resin particles are spherical, a roll-to-roll process can be applied when manufacturing dimming laminates, which can reduce the manufacturing cost of dimming laminates. Spherical shape is not limited to true spheres, but also includes approximately spherical shapes, such as shapes with an aspect ratio (major diameter / minor diameter) of 1.5 or less.

[0045] From the viewpoint of improving practicality, ensuring appropriate gaps, and effectively suppressing light leakage, the average particle size of the aforementioned colored resin particles is preferably 1 μm or more, more preferably 3 μm or more, and even more preferably 10 μm or more, and preferably 150 μm or less, more preferably 100 μm or less, and even more preferably 50 μm or less.

[0046] The particle size of the aforementioned colored resin particles refers to the diameter when the colored resin particles are truly spherical, and the diameter when the colored resin particles are other than truly spherical, assuming they are true spheres of equivalent volume. The particle size of the aforementioned colored resin particles is preferably the average particle size, and more preferably the number average particle size. The particle size of the aforementioned colored resin particles can be measured using any particle size distribution measuring device. For example, a particle size distribution measuring device utilizing principles such as laser light scattering, resistance value changes, or image analysis after imaging can be used. More specifically, as a method for measuring the particle size of colored resin particles, the following method can be cited: using a particle size distribution measuring device (Beckman Coulter's "Multisizer4"), the particle size of approximately 100,000 colored resin particles is measured, and the average value is calculated.

[0047] From the viewpoint of further controlling the gaps between substrates with higher precision, the aforementioned coloring resin particles preferably do not contain particles (coloring resin particles) having a particle size of 1.2 times or more than the average particle size, or contain particles (coloring resin particles) having a particle size of 1.2 times or more than the average particle size of 1000 ppm or less. From the viewpoint of further controlling the gaps between substrates with higher precision, the content of particles (coloring resin particles) having a particle size of 1.2 times or more than the average particle size is preferably 1000 ppm or less, more preferably 500 ppm or less, further preferably 100 ppm or less, and particularly preferably 50 ppm or less. From the viewpoint of further controlling the gaps between substrates with higher precision, the content of particles (coloring resin particles) having a particle size of 1.2 times or more than the average particle size is preferably 0 ppm (not contained).

[0048] The content of particles with a particle size of 1.2 times or more than the average particle size (colored resin particles) can be determined as follows: The colored resin particles are filtered using a filter with a pore size of 1.15 times the average particle size. The colored resin particles remaining on the filter are observed using an optical microscope, and the colored resin particles with a particle size of 1.2 times or more than the average particle size are counted. The counted number of colored resin particles is divided by the total number of filtered colored resin particles to calculate the content of particles with a particle size of 1.2 times or more than the average particle size (colored resin particles).

[0049] From the viewpoint of further controlling the gap between substrates with higher precision, the CV value of the particle size of the aforementioned colored resin particles is preferably 2.0% or more, more preferably 2.5% or more, and preferably 10% or less, more preferably 8.0% or less.

[0050] The CV value (coefficient of variation) of the particle size of the above-mentioned colored resin particles can be determined in the following manner.

[0051] CV value (%) = (ρ / Dn) × 100 ρ: Standard deviation of the particle size of the above-mentioned colored resin particles Dn: The average particle size of the above-mentioned colored resin particles

[0052] From the viewpoint of further controlling the gap between substrates with higher precision, the aspect ratio of the aforementioned colored resin particles is preferably 1.5 or less, more preferably 1.3 or less. The aspect ratio represents the length of the long axis and the length of the short axis. The aspect ratio is preferably determined by observing any 10 colored resin particles using an electron microscope or an optical microscope, setting the maximum and minimum diameters as the long axis and the short axis, respectively, and calculating the average aspect ratio of the long axis to the short axis for each spherical colored resin particle. There is no particular limitation on the lower limit of the aspect ratio of the aforementioned colored resin particles. The aspect ratio of the aforementioned colored resin particles can be 1.0 or more, or 1.1 or more.

[0053] From the viewpoint of improving the operability of the obtained dimming material and dimming laminate, the specific gravity of the aforementioned colored resin particles is preferably 1.5 or less, more preferably 1.4 or less, and even more preferably 1.3 or less. There is no particular limitation on the lower limit of the specific gravity of the aforementioned colored resin particles. The specific gravity of the aforementioned colored resin particles may be 1.0 or more, or may be 1.1 or more.

[0054] The colored resin particles of the present invention are suitably used as spacers. The colored resin particles of the present invention are particularly suitable as spacers in dimming laminates. The aforementioned colored resin particles can be used as spacers for dimming glass or as spacers for dimming films. Preferably, the aforementioned colored resin particles can be used as spacers for dimming glass or as spacers for dimming films.

[0055] The components of the colored resin particles are described in detail below.

[0056] <Resin Particles> The aforementioned colored resin particles comprise resin particles. The aforementioned colored resin particles and the aforementioned resin particles comprise resin. The aforementioned colored resin particles and the aforementioned resin particles preferably comprise a polymer. The aforementioned polymer can be obtained by polymerizing a polymeric component. The aforementioned colored resin particles and the aforementioned resin particles preferably comprise a component derived from the polymeric component. The aforementioned colored resin particles and the aforementioned resin particles preferably comprise a polymer containing a polymeric component.

[0057] Examples of resins used to form the aforementioned resin particles include: polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene; acrylic resins such as polymethyl methacrylate and polymethyl acrylate; polycarbonate, polyamide, phenol-formaldehyde resin, melamine-formaldehyde resin, benzoguanamine-formaldehyde resin, urea-formaldehyde resin, phenolic resin, melamine resin, benzoguanamine resin, urea resin, epoxy resin, unsaturated polyester resin, saturated polyester resin, polyethylene terephthalate, polyurethane, polyphenylene ether, polyacetal, polyimide, polyamide-imide, polyetheretherketone, polyether ether, and divinylbenzene polymers. The aforementioned divinylbenzene polymers may also be divinylbenzene copolymers. Examples of the aforementioned divinylbenzene copolymers include: divinylbenzene-styrene copolymers and divinylbenzene-(meth)acrylate copolymers. In order to easily control the 20% K value of the above resin particles within a suitable range, the resin used to form the above resin particles is preferably a polymer formed by polymerizing one or more polymeric monomers (polymeric components) having ethylene unsaturated groups.

[0058] When polymerizing a polymerizable monomer having an ethylene unsaturated group to obtain the above-mentioned resin particles, examples of such polymerizable monomers having an ethylene unsaturated group include: non-crosslinked monomers and crosslinked monomers.

[0059] As for the aforementioned non-crosslinking monomers, examples of vinyl compounds include: styrene monomers such as styrene, α-methylstyrene, and chlorostyrene; vinyl ether compounds such as methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, 1,4-butanediol divinyl ether, cyclohexanediol divinyl ether, and diethylene glycol divinyl ether; vinyl acetate compounds such as vinyl butyrate, vinyl laurate, and vinyl stearate; and halogen-containing monomers such as vinyl chloride and vinyl fluoride. Examples of (meth)acrylate compounds include: methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, and propyl methacrylate. Alkyl methacrylate compounds such as cetyl acrylate, stearyl methacrylate, cyclohexyl methacrylate, and isobutyl methacrylate; oxygen-containing methacrylate compounds such as 2-hydroxyethyl methacrylate, glyceryl methacrylate, polyoxyethylene methacrylate, and glycidyl methacrylate; nitrile monomers such as methacrylonitrile; halogen-containing methacrylate compounds such as trifluoromethyl methacrylate and pentafluoroethyl methacrylate; α-olefin compounds include, for example, diisobutylene, isobutylene, 1-linealene, ethylene, and propylene; conjugated diene compounds include, for example, isoprene and butadiene.

[0060] Regarding the aforementioned crosslinking monomers, examples of vinyl compounds include: divinylbenzene, 1,4-divinyloxybutane, and divinyl terephthalate; examples of (meth)acrylate compounds include: tetramethylolmethane tetra(meth)acrylate, polytetramethylene glycol diacrylate, tetramethylolmethane tri(meth)acrylate, tetramethylolmethane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate, glycerol tri(meth)acrylate, glycerol di(meth)acrylate, and polyethylene glycol di(meth)acrylate. Polyfunctional (meth)acrylate compounds include polypropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, and 1,4-butanediol di(meth)acrylate; allyl compounds include: triallyl (iso)cyanurate, triallyl trimellitate, diallyl phthalate, diallyl acrylamide, and diallyl ether; silane compounds include: tetramethoxysilane, tetraethoxysilane, triethylsilane, tributyldimethylsilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, isopropyltrimethoxysilane, isobutyltrimethoxysilane, cyclohexyltrimethoxysilane, and n-hexyltrimethoxysilane. Silane alkoxides including alkyl silane, n-octyltriethoxysilane, n-decyltrimethoxysilane, phenyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diisopropyldimethoxysilane, trimethoxysilylstyrene, γ-(meth)acryloxypropyltrimethoxysilane, 1,3-divinyltetramethyldisiloxane, methylphenyldimethoxysilane, diphenyldimethoxysilane, etc.; vinyltrimethoxysilane, vinyltriethoxysilane, dimethoxymethylvinylsilane, dimethoxyethylvinylsilane, diethoxymethylvinylsilane, diethoxyethylvinylsilane, ethylmethyldivinylsilane, methylvinyldimethoxysilane, etc. Silicon alkoxides containing polymerizable double bonds, such as methyl vinyl dimethoxysilane, methyl vinyl diethoxysilane, ethyl vinyl diethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyl dimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-propenyloxypropyltrimethoxysilane, etc.; cyclic siloxanes such as decamethylcyclopentasiloxane; modified (reactive) polysiloxanes such as single-terminated modified polysiloxane, double-terminated polysiloxane, and side-chain type polysiloxane; and carboxyl-containing monomers such as (meth)acrylic acid, maleic acid, and maleic anhydride.

[0061] The aforementioned resin particles can be obtained by polymerizing the aforementioned polymerizable monomers having vinyl unsaturated groups. The polymerization method is not particularly limited and can be achieved using known methods such as free radical polymerization, ionic polymerization, condensation polymerization, addition polymerization, living polymerization, and living free radical polymerization.

[0062] The aforementioned resin particles can be easily obtained by free radical polymerization using polymerizable monomers with ethylene unsaturated groups. For example, they can be obtained by suspension polymerization in the presence of a free radical polymerization initiator, or by seed polymerization and dispersion polymerization, where the monomer and free radical polymerization initiator are swelled together using non-crosslinked seed particles.

[0063] From the viewpoint of further controlling the gaps between substrates with higher precision, the aforementioned polymeric component preferably contains a polyfunctional (meth)acrylate compound. That is, from the viewpoint of further controlling the gaps between substrates with higher precision, the aforementioned colored resin particles and the aforementioned resin particles preferably contain components derived from polyfunctional (meth)acrylate compounds.

[0064] The aforementioned polyfunctional (meth)acrylate compounds can be difunctional (meth)acrylate compounds, trifunctional (meth)acrylate compounds, or (meth)acrylate compounds with more than three functions, or (meth)acrylate compounds with more than four functions. Only one of the aforementioned polyfunctional (meth)acrylate compounds can be used, or two or more can be used in combination.

[0065] From the viewpoint that it is easy to control the 20% K value of the above-mentioned colored resin particles within a suitable range, the above-mentioned colored resin particles and the above-mentioned resin particles are preferably containing difunctional (meth)acrylate compounds or trifunctional (meth)acrylate compounds.

[0066] The aforementioned polyfunctional (meth)acrylate compounds are preferably polytetramethylene glycol di(meth)acrylate or dipentaerythritol tetra(meth)acrylate.

[0067] Of the aforementioned 100% by weight of the colored resin particles, the content of the component derived from the polyfunctional (meth)acrylate compound is preferably 10% by weight or more, more preferably 50% by weight or more, further preferably 55% by weight or more, particularly preferably 60% by weight or more, and preferably 95% by weight or less, more preferably 90% by weight or less, and further preferably 80% by weight or less. If the content of the component derived from the polyfunctional (meth)acrylate compound is above or below the aforementioned lower limit and below the aforementioned upper limit, the gap between the substrates can be controlled with even higher precision. From the viewpoint of controlling the gap between the substrates with even higher precision, the aforementioned colored resin particles preferably contain the component derived from the polyfunctional (meth)acrylate compound in a content of 50% by weight or more of 100% by weight of the colored resin particles.

[0068] The content of the polyfunctional (meth)acrylate compound in 100% by weight of the aforementioned resin particles is preferably 10% by weight or more, more preferably 50% by weight or more, more preferably 60% by weight or more, particularly preferably 65% ​​by weight or more, and preferably 95% by weight or less, more preferably 90% by weight or less, and more preferably 80% by weight or less. If the content of the polyfunctional (meth)acrylate compound is above the aforementioned lower limit and below the aforementioned upper limit, the gap between the substrates can be controlled with even higher precision.

[0069] <Coloring agent> The aforementioned colored resin particles contain a colorant. The colorant may be disposed within the resin particles or on the surface of the resin particles. From the viewpoint of improving the conductivity reliability of the obtained dimming laminate, the colorant is preferably disposed within the resin particles. The colorant is preferably contained within the resin particles.

[0070] Examples of colorants mentioned above include inorganic particles, dyes, and pigments. Only one type of colorant may be used, or two or more may be used in combination.

[0071] Examples of such inorganic particles include: carbon black particles, carbon nanotube particles, titanium black particles, graphene particles, iron oxide particles, zinc oxide particles, calcium carbonate particles, aluminum oxide particles, kaolin clay particles, calcium silicate particles, magnesium oxide particles, magnesium hydroxide particles, aluminum hydroxide particles, magnesium carbonate particles, talc particles, feldspar powder particles, mica particles, barite particles, barium carbonate particles, titanium oxide particles, silicon dioxide particles, and glass beads. Carbon black particles or titanium black particles are preferred among these inorganic particles.

[0072] The average particle size of the aforementioned inorganic particles is preferably 0.01 μm or more, more preferably 0.5 μm or more, and preferably 100 μm or less, more preferably 50 μm or less, and even more preferably 10 μm or less. The aforementioned average particle size represents the weight-average particle size. The aforementioned average particle size can be measured using a light scattering measuring device, employing a laser as the light source, and by means of dynamic light scattering. Examples of such light scattering measuring devices include, for instance, the "DLS-6000AL" manufactured by Otsuka Electronics Co., Ltd.

[0073] Examples of such dyes include: pyrene dyes, amino ketone dyes, anthraquinone dyes, and azo dyes.

[0074] Examples of the aforementioned pyrene dyes include Solvent Green5 (CAS79869-59-3) and Solvent Green7 (CAS6358-69-6).

[0075] Examples of the above-mentioned amino ketone dyes include: Solvent Yellow 98 (CAS12671-74-8), Solvent Yellow 85 (CAS12271-01-1), Solvent Red 179 (CAS8910-94-5), and Solvent Red 135 (CAS71902-17-5).

[0076] Examples of anthraquinone dyes mentioned above include: Solvent Yellow 163 (CAS13676091-0), Solvent Red 207 (CAS15958-69-6), Disperse Red 92 (CAS12236-11-2), Solvent Violet 13 (CAS81-48-1), Disperse Violet 31 (CAS6408-72-6), Solvent Blue 97 (CAS61969-44-6), Solvent Blue 45 (CAS37229-23-5), Solvent Blue 104 (CAS116-75-6), and Disperse Blue 214 (CAS104491-84-1).

[0077] Examples of the aforementioned azo dyes include Solvent Yellow 30 (CAS3321-10-4), Solvent Red 164 (CAS70956-30-8), and Disperse Blue 146 (CAS88650-91-3).

[0078] The aforementioned colorant preferably contains pigments. In this case, even when used as a spacer and exposed for a long period of time, it is not easy to fade, and light leakage can be suppressed for a long time. Furthermore, even if the coloring resin particles are damaged and the internal colorant flows out, short circuits can be suppressed. As a result, the conductivity reliability of the obtained dimming laminate can be further improved.

[0079] Pigments can be organic or inorganic. Organic pigments may or may not contain metal atoms. Pigments can be red, blue, yellow, or black. Only one type of pigment may be used, or two or more may be used in combination.

[0080] From the viewpoint of further effectively and for a longer period of time suppressing light leakage, effectively suppressing color change, and improving the conductivity reliability of the obtained light-tuning laminate, the above-mentioned pigment is preferably an organic pigment, more preferably a black pigment, and even more preferably an organic black pigment.

[0081] Examples of organic black pigments include: anthraquinone pigments, anthraquinone pigments, dianthraquinone pigments, anthraquinone pigments, styridine pigments, flavonoid pigments, pyrrolopyrroledione pigments, quinacridone pigments, pyrrolopyrroledione pigments, indigo-thioindigo pigments, pyrenone pigments, perylene pigments, phthalocyanine pigments, halogenated phthalocyanine pigments, indoline pigments, isoindoline pigments, isoindoline ketone pigments, indanthrene pigments, diazonium pigments, quinoline ketone pigments, azo nickel pigments, metal complex pigments, azo pigments (insoluble azo pigments, soluble azo pigments, high molecular weight azo pigments, and methylene azo black pigments), and aniline black pigments, etc.

[0082] From the viewpoint of further effectively and persistently suppressing light leakage and improving the conductivity reliability of the obtained dimming laminate, the aforementioned colorant preferably contains organic black pigments, titanium black particles, or carbon black particles, more preferably organic black pigments, and even more preferably azo pigments or perylene pigments. Furthermore, from the viewpoint of easily controlling the brightness L0* of the aforementioned colored resin particles before light irradiation and the brightness L540* of the aforementioned colored resin particles after light irradiation within a suitable range, the aforementioned colorant preferably contains azo pigments, titanium black particles, or carbon black particles.

[0083] The average particle size of the aforementioned organic black pigment is preferably 1 nm or more, more preferably 10 nm or more, and preferably 500 nm or less, more preferably 300 nm or less, and even more preferably 100 nm or less. The aforementioned average particle size represents the weight-average particle size. The aforementioned average particle size can be measured using a light scattering measuring device, employing a laser as the light source and a dynamic light scattering method. Examples of such light scattering measuring devices include, for instance, the "DLS-6000AL" manufactured by Otsuka Electronics Co., Ltd.

[0084] Preferably, the aforementioned colored resin particles contain 20% or less of the aforementioned colorant per 100% by weight. In the aforementioned colored resin particles, the content of the aforementioned colorant per 100% by weight is preferably 0.5% or more, more preferably 1.0% or more, and even more preferably 3.0% or more, and preferably 20% or less, more preferably 15% or less, and even more preferably 10% or less. If the content of the aforementioned colorant is at or above the aforementioned lower limit, light leakage can be suppressed more effectively. If the content of the aforementioned colorant is below the aforementioned upper limit, the insulation reliability of the aforementioned colored resin particles can be further improved, and as a result, the conductivity reliability of the obtained dimming laminate can be further improved. When the aforementioned colored resin particles contain a plurality of colorants, the aforementioned colorant content refers to the total content of the plurality of colorants.

[0085] <Other Ingredients> The aforementioned colored resin particles may also contain other components as needed. Examples of such other components include polymerization initiators, pigment dispersants, resin particle dispersants, and surfactants. Only one of these other components may be used, or two or more may be used in combination.

[0086] (Light-adjustable stacked layers) The dimming laminate of the present invention comprises a first substrate, a second substrate, and a dimming layer disposed between the first substrate and the second substrate. The dimming layer of the dimming laminate of the present invention comprises the aforementioned colored resin particles.

[0087] Because the dimming stack of the present invention has the above-described structure, the gap between the substrates can be controlled with high precision, and the conductivity reliability of the obtained dimming stack can be improved.

[0088] The aforementioned dimming layer can be a PDLC (Polymer Dispersed Liquid Crystal) dimming layer or an SPD (Suspended Particle Device) dimming layer. Preferably, the dimming layer is an SPD or PDLC dimming layer. From the viewpoint of further effectively realizing the effects of the present invention, the dimming layer is more preferably a PDLC dimming layer. The aforementioned dimming layer may also not be a liquid crystal display device.

[0089] The aforementioned dimming laminate may or may not have a curved surface. Preferably, the dimming laminate has a curved surface. The aforementioned dimming laminate may also have a bent or curved shape. Preferably, the aforementioned dimming laminate has a bent or curved shape, and is preferably used in a bent or curved shape. The aforementioned dimming laminate may also have a bent portion or a curved portion. The aforementioned dimming laminate, the aforementioned first substrate, and the aforementioned second substrate are preferably flexible to form a bent or curved shape. When the aforementioned dimming laminate has a curved surface, the curvature of the curved surface of the aforementioned dimming laminate is preferably 300 R or more and 1800 R or less. Even if the above-mentioned dimming laminate has a curved surface, or the curvature of the curved surface of the above-mentioned dimming laminate satisfies the above-mentioned preferred state, by using the adhesive particles of the present invention, the gap between the substrates can be controlled as a whole with high precision, and light leakage can be suppressed.

[0090] The aforementioned dimming laminate is preferably used for window glass or partitions in vehicles. Examples of such vehicles include cars, ships, and aircraft. The aforementioned dimming laminate is preferably used for window glass or partitions in vehicles, ships, and aircraft. The aforementioned dimming laminate is preferably a window glass or partition, more preferably a window glass or partition in vehicles, ships, and aircraft. The aforementioned dimming laminate can be a window glass in vehicles, ships, and aircraft, or it can be a partition. The aforementioned vehicle is preferably a transportation vehicle. The aforementioned partition can also be a component disposed between seats in a vehicle to separate seats.

[0091] Next, with reference to the drawings, specific embodiments of the present invention will be described.

[0092] Figure 1 is a schematic cross-sectional view of the colored resin particles according to the first embodiment of the present invention.

[0093] The colored resin particles 1 comprise resin particles and a colorant. Regarding the colored resin particles 1, when measuring the luminance of the colored resin particles before light irradiation and after light irradiation with a cumulative light intensity of 540 MJ / m² according to the L*a*b* colorimetric system of JIS Z8781-4:2013, the luminance L0* of the colored resin particles before light irradiation is 0 to 60. Furthermore, in the above measurements, the ratio of the luminance L0* of the colored resin particles before light irradiation to the luminance L540* of the colored resin particles after light irradiation is 0.3 or higher.

[0094] Figure 2 is a schematic cross-sectional view of a PDLC-type dimming laminate containing the colored resin particles of the first embodiment of the present invention. Figure 3 is a schematic cross-sectional view of an SPD-type dimming laminate containing the colored resin particles of the first embodiment of the present invention. Furthermore, in Figures 2 and 3, for ease of illustration, the size, thickness, shape, and amount of the dimming layer and the colored resin particles are appropriately modified from their actual size and shape.

[0095] The PDLC dimming laminate 11 shown in Figure 2 includes a first substrate 2, a second substrate 3, and a dimming layer 4. The dimming layer 4 is sandwiched between the first substrate 2 and the second substrate 3. The dimming layer 4 is disposed between the first substrate 2 and the second substrate 3. Alternatively, a sealant may be disposed around the dimming layer 4 between the first substrate 2 and the second substrate 3.

[0096] The dimming layer 4 comprises colored resin particles 1, liquid crystal capsules 4A, and an adhesive 4B. The liquid crystal capsules 4A are liquid crystal materials. The liquid crystal capsules 4A are dispersed in the adhesive 4B. The liquid crystal capsules 4A are held in a capsule shape within the adhesive 4B. The liquid crystal material can be dispersed in the adhesive in a capsule shape, or the liquid crystal material can be dispersed in the adhesive in the form of a continuous phase.

[0097] The colored resin particles 1 are in contact with the first substrate 2 and the second substrate 3. The colored resin particles 1 control the gap between the first substrate 2 and the second substrate 3.

[0098] Electrodes (not shown) are formed on the surface of the first substrate 2 and the surface of the second substrate 3. Examples of materials for these electrodes include indium tin oxide (ITO). Preferably, the electrodes are transparent electrodes.

[0099] When no electric field is applied to the PDLC dimming stack 11, the liquid crystal molecules in the liquid crystal capsule 4A are not uniformly aligned. As a result, the refractive index of the binder 4B and the liquid crystal material are different, which causes the incident light to be scattered in the binder 4B and become opaque.

[0100] If an electric field is applied to the dimming stack 11 of the PDLC method, the liquid crystal molecules inside the liquid crystal capsule 4A align in a direction parallel to the electric field. In this state, the refractive index of the binder 4B and the liquid crystal material becomes the same, so light can pass through, and it becomes transparent.

[0101] The dimming laminate 21 of the SPD method shown in Figure 3 includes: a first substrate 2, a second substrate 3, and a dimming layer 5. The dimming layer 5 is sandwiched between the first substrate 2 and the second substrate 3.

[0102] The dimming layer 5 comprises colored resin particles 1, droplets 5A of a light-modifying suspension, and a resin matrix 5B. The droplets 5A of the light-modifying suspension are dispersed in the resin matrix 5B. The droplets 5A of the light-modifying suspension are maintained in a droplet state within the resin matrix 5B.

[0103] The droplets 5A of the light-modified suspension contain a dispersion medium 5Aa and light-modifying particles 5Ab. The light-modifying particles 5Ab are dispersed in the dispersion medium 5Aa.

[0104] The colored resin particles 1 are in contact with the first substrate 2 and the second substrate 3. The colored resin particles 1 control the gap between the first substrate 2 and the second substrate 3.

[0105] Electrodes (not shown) are formed on the surface of the first substrate 2 and the surface of the second substrate 3. Examples of materials for the electrodes include indium tin oxide (ITO). Preferably, the electrodes are transparent electrodes.

[0106] When no electric field is applied to the dimming stack 21 of the SPD method, due to the Brownian motion of the light-adjusting particles 5Ab dispersed in the dispersion medium 5Aa that constitutes the light-adjusting suspension, the incident light is absorbed, scattered, or reflected by the light-adjusting particles 5Ab, and the incident light cannot pass through the dimming layer 5.

[0107] If an electric field is applied to the dimming stack 21 of the SPD method, the light-adjusting particles 5Ab are aligned in a direction parallel to the electric field. Therefore, incident light can pass between the aligned light-adjusting particles 5Ab and can pass through the dimming layer 5.

[0108] <Dimming Layer> The aforementioned dimming layer preferably possesses dimming properties. Dimming properties refer to the property that the amount of incident light can be adjusted by changing the visible light transmittance depending on whether an electric field is applied. The aforementioned dimming layer contains the aforementioned colored resin particles.

[0109] (PDLC method) The dimming layer preferably includes an adhesive and a liquid crystal material dispersed in the adhesive.

[0110] The liquid crystal material described above is not particularly limited; any liquid crystal material can be used as long as it has the property that its orientation changes according to the application of an electric field. The liquid crystal material can be dispersed in the binder as a continuous phase, or it can be dispersed in the binder in the form of liquid crystal drops or liquid crystal capsules. Examples of liquid crystal materials include nematic liquid crystals and cholesteric liquid crystals.

[0111] Examples of materials for the aforementioned nematic liquid crystals include: cyanobiphenyl-based, phenyl ester-based, oxoazobenzene-based, fluorinated biphenyl-based, carbonate-based, and Schiff base-based materials. Only one of these nematic liquid crystal materials may be used, or two or more may be used in combination.

[0112] Examples of materials for the aforementioned cholesterol-type liquid crystals include: steroid-based cholesterol derivatives, Schiff base-based, azo-based, azo oxide-based, benzoic acid ester-based, biphenyl-based, terphenyl-based, cyclohexylcarboxylic acid ester-based, phenylcyclohexane-based, biphenylcyclohexane-based, pyrimidine-based, dialkyl-based, cyclohexylcyclohexane ester-based, cyclohexylethane-based, cyclohexane-based, diphenylacetylene-based, alkenyl-based, piracene-based, condensed polycyclic liquid crystals, and other nematic or smectic liquid crystals, as well as materials formed by adding chiral components containing optically active materials such as Schiff base-based, azo-based, ester-based, and biphenyl-based materials to mixed liquid crystals of these types. Only one of the aforementioned cholesterol-type liquid crystal materials may be used, or two or more may be used in combination.

[0113] The aforementioned adhesive retains the liquid crystal material and inhibits its flow. There are no particular limitations on the adhesive, as long as it does not dissolve in the liquid crystal material, possesses strength to withstand external forces, and exhibits high transmittance for both reflected and incident light. Examples of materials that can be used as the adhesive include water-soluble polymers such as gelatin, polyvinyl alcohol, cellulose derivatives, polyacrylic acid polymers, ethylene ethylimide, polyethylene oxide, polyacrylamide, polystyrene sulfonate, polyamidine, and isoprene sulfonate polymers, as well as water-emulsifiable materials such as fluoropolymers, polysiloxane resins, acrylic resins, urethane resins, and epoxy resins. Only one type of adhesive material may be used, or two or more may be used in combination.

[0114] The aforementioned adhesive is preferably cross-linked using a cross-linking agent. The cross-linking agent is not particularly limited, as long as it forms cross-links between the adhesives, enabling the adhesive to achieve hardening, insolubility, or insolubility. Examples of such cross-linking agents include: acetaldehyde, glutaraldehyde, glyoxal, potassium aluminum sulfate hydrate (a polyvalent metal salt compound), diacetic acid dihydrazine, melamine-formaldehyde oligomer, ethylene glycol diglycidyl ether, polyamide epichlorohydrin, and polycarbodiimide. Only one cross-linking agent may be used, or two or more may be used in combination.

[0115] (SPD method) The aforementioned dimming layer preferably includes a resin matrix and a light-modifying suspension dispersed in the resin matrix.

[0116] The aforementioned light-modifying suspension comprises a dispersion medium and light-modifying particles dispersed in the dispersion medium.

[0117] Examples of light-modifying particles include: carbon-based materials such as polyiodides and carbon black; metallic materials such as copper, nickel, iron, cobalt, chromium, titanium, and aluminum; and inorganic compound materials such as silicon nitride, titanium nitride, and alumina. Alternatively, these materials may be polymer-coated particles. Only one type of light-modifying particle may be used, or two or more may be used in combination.

[0118] The aforementioned dispersion medium disperses the light-adjusting particles in a flowable state. Preferably, the dispersion medium is a material that selectively adheres to and coats the light-adjusting particles, acting upon phase separation from the resin matrix to allow the light-adjusting particles to move towards the separated droplet phase. It is non-electrically conductive and has no affinity for the resin matrix. Furthermore, the dispersion medium is preferably a liquid copolymer with a refractive index similar to that of the resin matrix when forming the light-adjusting laminate. As the liquid copolymer, it is preferably a (meth)acrylate oligomer having fluorine or hydroxyl groups, and more preferably a (meth)acrylate oligomer having both fluorine and hydroxyl groups. When using such a copolymer, the fluorine or hydroxyl monomer units face the light-adjusting particles, while the remaining monomer units stabilize the droplets of the light-adjusting suspension within the resin matrix. Therefore, the light-adjusting particles are easily dispersed within the light-adjusting suspension, and upon phase separation from the resin matrix, they are easily guided into the separated droplets.

[0119] Examples of the above-mentioned oligomers of (meth)acrylates having fluorine or hydroxyl groups include: 2,2,2-trifluoroethyl methacrylate / butyl acrylate / 2-hydroxyethyl acrylate copolymer, 3,5,5-trimethylhexyl acrylate / 2-hydroxypropyl acrylate / fumaric acid copolymer, butyl acrylate / 2-hydroxyethyl acrylate copolymer, 2,2,3,3-tetrafluoropropyl acrylate / butyl acrylate / 2-hydroxyethyl acrylate copolymer, 1H,1H,5H-octafluoropentyl acrylate / butyl acrylate / 2-hydroxyethyl acrylate copolymer, acrylic acid... 1H,1H,2H,2H-heptafluorodecyl acrylate / butyl acrylate / 2-hydroxyethyl acrylate copolymer, 2,2,2-trifluoroethyl methacrylate / butyl acrylate / 2-hydroxyethyl acrylate copolymer, 2,2,3,3-tetrafluoropropyl methacrylate / butyl acrylate / 2-hydroxyethyl acrylate copolymer, 1H,1H,5H-octafluoropentyl methacrylate / butyl acrylate / 2-hydroxyethyl acrylate copolymer, and 1H,1H,2H,2H-heptafluorodecyl methacrylate / butyl acrylate / 2-hydroxyethyl acrylate copolymer, etc. Furthermore, these (meth)acrylate oligomers are preferably those containing both fluorine and hydroxyl groups.

[0120] The weight average molecular weight of the above-mentioned (meth)acrylate oligomers is preferably 1,000 or more, more preferably 2,000 or more, and more preferably 20,000 or less, and more preferably 10,000 or less.

[0121] The aforementioned dimming layer can be made using the resin material used to form the aforementioned resin matrix and the aforementioned light-adjusting suspension.

[0122] The aforementioned resin material is preferably a resin material that is cured by irradiation energy lines. Examples of resin materials that are cured by irradiation energy lines include polymer compositions comprising photopolymerization initiators and polymeric compounds that are cured by energy lines such as ultraviolet light, visible light, and electron beams. Examples of such polymer compositions include polymeric compositions comprising polymeric monomers having vinyl unsaturated groups and photopolymerization initiators. Examples of such polymeric monomers having vinyl unsaturated groups include non-crosslinked monomers and crosslinked monomers.

[0123] Examples of non-crosslinkable monomers mentioned above can be cited as examples of non-crosslinkable monomers. Examples of crosslinkable monomers mentioned above can be cited as examples of crosslinkable monomers.

[0124] Examples of photopolymerization initiators include: 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-(4-(2-hydroxyethoxy)phenyl)-2-hydroxy-2-methyl-1-propane-1-one, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2-hydroxy-2-methyl-1-phenylpropane-1-one, and (1-hydroxycyclohexyl)phenyl ketone.

[0125] The aforementioned resin materials may include organic solvent-soluble resins, thermoplastic resins, and poly(meth)acrylic acid, etc. Furthermore, the aforementioned resin materials may include various additives such as anti-coloring agents, antioxidants, and adhesion promoters, and may also include solvents.

[0126] <First substrate and second substrate> The first substrate mentioned above is preferably a transparent substrate. The second substrate mentioned above is preferably a transparent substrate. The transparent substrate mentioned above is, for example, a substrate that is light-transmitting (light-transmitting substrate). For example, light passes through the transparent substrate from one side to the other side. For example, when observing a substance on the other side from one side of the transparent substrate through the transparent substrate, the substance can be observed. Transparency also includes translucency. The transparent substrate can be colorless transparent or colored transparent.

[0127] The materials of the first and second substrates are not particularly limited. The materials of the first and second substrates may be the same or different. Examples of materials for the first and second substrates include glass and resin films. Examples of glass include: soda-lime glass, lead glass, borosilicate glass, and various other types of glass used in construction, as well as functional glass such as heat-reflective glass, heat-absorbing glass, and tempered glass. Examples of resin films include: polyester films such as polyethylene terephthalate, polyolefin films such as polypropylene, and resin films such as acrylic resin films. In terms of superior transparency, formability, adhesion, and processability, the first and second substrates are preferably resin substrates, more preferably resin films, and even more preferably polyethylene terephthalate films.

[0128] The first and second substrates described above are preferably composed of a substrate body and a transparent conductive film formed on the surface of the substrate body, so that an electric field for dimming can be applied. Examples of the conductive film include indium tin oxide (ITO), SnO2, and In2O3. The conductive film is preferably a transparent conductive film.

[0129] From the viewpoint of further improving the visibility of the dimming laminate, the visible light transmittance of the first substrate and the second substrate is preferably 75% or more, and more preferably 80% or more.

[0130] The visible light transmittance of the first and second substrates can be measured by spectrophotometry and in accordance with ISO 13837:2008.

[0131] The present invention will be specifically described below with reference to examples and comparative examples. The present invention is not limited to the following examples.

[0132] Prepare the following materials.

[0133] (Coloring agent): Carbon black (inorganic black pigment) Titanium black (inorganic black pigment) Azo pigments (organic black pigments)

[0134] (Materials for resin particles): styrene Divinylbenzene (96% purity by weight, manufactured by Nippon Steel Chemical Materials Co., Ltd., "DVB960") Polytetramethylene glycol diacrylate (a multifunctional (meth)acrylate compound, manufactured by Kyoei Chemical Co., Ltd. as "PTMGA250") Pentaerythritol tetraacrylate (a polyfunctional (meth)acrylate compound, manufactured by Shin-Nakamura Chemical Industry Co., Ltd. as "A-TMMT")

[0135] (1) Production of coloring resin particles (Example 1) Five parts by weight of carbon black were added to 30 parts by weight of divinylbenzene and 70 parts by weight of polytetramethylene glycol diacrylate, and the mixture was stirred to obtain a monomer mixture. 2000 parts by weight of a 2.5% aqueous solution of polyvinyl alcohol with a molecular weight of approximately 2000 dissolved in pure water were added to a reactor. The obtained monomer mixture was then added and stirred to adjust the particle size by achieving a specific droplet size. Subsequently, the mixture was heated at 90°C for 9 hours to carry out the polymerization reaction of the monomer droplets, thereby obtaining particles. The obtained particles were washed several times with hot water and acetone, and then graded to recover the colored resin particles.

[0136] (Examples 2-15) Except for changes to the materials and contents (by weight %) of the colorant and resin particles as shown in Tables 1-4, the colored resin particles were prepared in the same manner as in Example 1.

[0137] (Comparative Example 1) Except for changes to the material and content (by weight %) of the resin particles as shown in Table 4, the resin particles were prepared in the same manner as in Example 1. In Comparative Example 1, no colorant was used.

[0138] The following light-adjusting laminates were prepared using the colored resin particles of Examples 1-15 and the resin particles of Comparative Example 1.

[0139] (2) Fabrication of a dimming layer SPD method of dimming stacked layers: A dimming film having a known SPD layer is prepared by dispersing 5% by weight of colored resin particles or resin particles from Comparative Example 1 between two PET films coated with transparent and conductive ITO. A dimming laminate of the SPD type is prepared by sandwiching the dimming film between two transparent glass sheets.

[0140] PDLC dimming stack: A dimming film having a known PDLC layer is prepared by dispersing 5% by weight of colored resin particles or resin particles from Comparative Example 1 between two PET films coated with transparent and conductive ITO. A dimming laminate of the PDLC type is prepared by sandwiching the dimming film between two transparent glass sheets.

[0141] (evaluate) (1) Average particle size For the obtained colored resin particles and the resin particles of Comparative Example 1, the particle size of approximately 100,000 particles was measured using a particle size distribution measuring device (Beckman Coulter's "Multisizer 4"), and the average particle size and standard deviation were determined. Furthermore, the content (ppm) of particles (colored resin particles or resin particles) with a particle size of 1.2 times or more than the average particle size was determined using the above method.

[0142] (2) CV value of particle size The CV value of the particle size was calculated for the obtained colored resin particles and the resin particles of Comparative Example 1 using the above method.

[0143] (3) Specific gravity The specific gravity of the obtained colored resin particles and the resin particles of Comparative Example 1 was determined using the "AccuPyc II 1345 series" manufactured by Shimadzu Corporation.

[0144] (4) Brightness The obtained colored resin particles and 100 mg of resin particles from Comparative Example 1 were thinly spread on an adhesive tape (75 mm long, 15 mm wide) attached to a glass slide and subjected to a 30-second blower to prepare a sample loaded with colored resin particles. The sample was irradiated for 588 hours using a daylight-type carbon arc lamp at an illuminance of 255 W / m² (cumulative light intensity: 540 MJ / m²). The brightness was measured at 10 random locations on the sample before and after irradiation using a colorimeter (SATOTECH "TES-3250") with a measurement range of an 8 mm diameter circle. The average values ​​were set as brightness L0* and brightness L540*. The ratio (L0* / L540*) was then calculated.

[0145] (5) 20% K value The 20% K value of the obtained colored resin particles and the resin particles of Comparative Example 1 was determined using the "Fischerscope H-100" manufactured by Fischer Corporation by the above method.

[0146] (6) Light leakage suppression Using the obtained colored resin particles as spacers for TN (torsional nematic) type liquid crystal display elements, TN type liquid crystal display elements are manufactured by the following method.

[0147] SiO2 films were deposited on one side of the first and second transparent substrates (transparent glass plates, 150 mm × 150 mm) using CVD, and then ITO films were formed on the entire surface of the SiO2 films by sputtering. Subsequently, a polyimide alignment film ("SE-7210" ​​manufactured by Nissan Chemical Co., Ltd.) was prepared by spin coating and calcined at 280°C for 90 minutes to form the polyimide alignment film. Following a rubbing treatment, the obtained colored resin particles were dispersed onto the alignment film side of the first transparent substrate using a dry dispersion machine ("DISPA-μR" manufactured by Nisshin Engineering Co., Ltd.) at a rate of 20 to 100 particles per mm². A peripheral sealant (main agent: SE4500, hardener: HAVEN CHEMICAL) is applied around the periphery of the second transparent substrate. The substrates are then aligned and bonded together with the first and second transparent substrates at a 90° twist angle. The sealant is then cured at 160°C for 90 minutes to create a blank cell. TN-type liquid crystal (Merck's "MLC-6222") is injected into the obtained blank cell. The injection port is then blocked using a bonding machine (Sekisui Chemicals Co., Ltd.'s "Photolec A-780") to create a TN-type liquid crystal display element, which is then heat-treated at 120°C for 30 minutes.

[0148] A TN-type liquid crystal display element, obtained by clamping a polarizing film arranged in an orthogonal polarization configuration to achieve a normal white display mode, was used. While applying a 7V voltage, the light leakage state of the colored resin particles was observed using a digital microscope (Keyence VHX-2000). With the image magnification set to 200x, the proportion of light-leaking colored resin particles was calculated in any five fields of view. The same calculation was performed for the resin particles of Comparative Example 1. Light leakage suppression was determined using the following criteria.

[0149] [Criteria for Judging Light Leakage Suppression] ○○: The percentage of light-leaking colored resin particles is less than 1%. ○: The percentage of light-leaking colored resin particles is 1% or more but less than 3%. △: The percentage of light-leaking colored resin particles is 3% or more but less than 5%. ×: The percentage of light-leaking colored resin particles is 5% or higher.

[0150] (7) Inhibition of the destruction of coloring resin particles The obtained light-adjusting laminate was pressurized at 2 kg / cm² for 10 minutes and then observed using a digital microscope (Keyence VHX-2000) to measure the ratio of the number of damaged colored resin particles. The inhibition of colored resin particle damage was determined using the following criteria.

[0151] [Criteria for determining the inhibitory effect of coloring resin particles on destructive properties] ○○: The percentage of damaged colored resin particles is less than 0.01%. ○: The percentage of damaged colored resin particles is 0.01% or more but less than 0.1%. △1: The percentage of damaged colored resin particles is 0.1% or more but less than 0.5%. △2: The percentage of damaged colored resin particles is 0.5% or more but less than 1.0%. ×: The percentage of damaged colored resin particles is 1.0% or higher.

[0152] (8) Conductivity reliability of the dimming layer For the obtained dimming stack, the connection resistance between the upper and lower electrodes is measured using the four-terminal method, and the average value of the connection resistance is calculated. Furthermore, based on the relationship voltage = current × resistance, the voltage flowing through a certain current is measured, and the connection resistance can be determined from this. The conductivity reliability of the dimming stack is determined using the following criteria.

[0153] [Criteria for Determining the Conductivity Reliability of Modulated Stacks] ○○: Connection resistance is 1.0 × 10¹⁰ Ω or higher. ○: Connection resistance is 1.0×10⁹ Ω / □ or higher but less than 1.0×10¹⁰ Ω / □ △1: Connection resistance is 1.0×10⁸Ω / □ or higher but less than 1.0×10⁹Ω / □ △2: Connection resistance is 1.0×10⁷Ω / □ or higher but less than 1.0×10⁸Ω / □ ×: Connection resistance not reaching 1.0 × 10⁷ Ω / □

[0154] (9) Gap control For the obtained dimming laminate, the maximum and minimum distances between the substrates (transparent glass) were measured. The gap control was determined using the following criteria.

[0155] [Criteria for Judging Gap Control] ○○: The maximum distance between substrates is less than 1.05 times the minimum distance. ○: The maximum distance between substrates is more than 1.05 times but less than 1.10 times the minimum distance. △1: The maximum distance between substrates is more than 1.10 times but less than 1.15 times the minimum distance. △2: The maximum distance between substrates is more than 1.15 times but less than 1.20 times the minimum distance. ×: The maximum distance between substrates is more than 1.20 times the minimum distance.

[0156] The composition and results of the colored resin particles are shown in Tables 1-4 below.

[0157] [Table 1] Example 1 Example 2 Example 3 Example 4 Colored resin particles Colorant carbon black weight% 4.8 - - - Titanium Black weight% - 4.8 - - Azo pigments weight% - - 4.8 4.8 resin particles styrene weight% - - - - Divinylbenzene weight% 28.6 28.6 28.6 28.6 Polytetramethylene glycol diacrylate weight% 66.7 66.7 66.7 66.7 Pentaerythritol tetraacrylate weight% - - - - Average particle size μm 20 20 20 20 Content of particles with a diameter more than 1.2 times the average particle size ppm 10 10 10 10 CV value of particle size % 4 4 4 4 proportion - 1.16 1.23 1.17 1.14 brightness L 0* - 21.39 24.94 22.34 23.08 L 540* - 22.67 30.81 27.88 24.53 L 0* / L 540* - 0.94 0.81 0.80 0.94 20% K value N / mm 2 1610 1450 1270 1080 Volume resistivity Ω·cm 1.0×10 11 1.0×10 12 1.0×10 15 1.0×10 15 evaluate The presence or absence of colorant - have have have have Light leakage suppression - ○○ ○○ ○○ ○○ Inhibitory properties of colored resin particles - ○○ ○○ ○○ ○○ Conductivity reliability of dimming stack - ○ ○ ○○ ○○ Gap control - ○○ ○○ ○○ ○○

[0158] [Table 2] Example 5 Example 6 Example 7 Example 8 Colored resin particles Colorant carbon black weight% - - - - Titanium Black weight% - - - - Azo pigments weight% 4.8 4.8 4.8 4.8 resin particles styrene weight% 47.6 19.0 23.8 9.5 Divinylbenzene weight% - 9.5 23.8 38.1 Polytetramethylene glycol diacrylate weight% 47.6 66.7 - - Pentaerythritol tetraacrylate weight% - - 47.6 47.6 Average particle size μm 20 20 20 20 Content of particles with a diameter more than 1.2 times the average particle size ppm 10 10 10 10 CV value of particle size % 4 4 4 4 proportion - 1.17 1.17 1.17 1.17 brightness L 0* - 22.34 22.34 22.34 22.34 L 540* - 27.88 27.88 27.88 27.88 L 0* / L 540* - 0.80 0.80 0.80 0.80 20% K value N / mm 2 300 700 3500 4500 Volume resistivity Ω·cm 1.0×10 12 1.0×10 12 1.0×10 12 1.0×10 12 evaluate The presence or absence of colorant - have have have have Light leakage suppression - ○○ ○○ ○○ ○○ Inhibitory properties of colored resin particles - ○○ ○○ ○ △1 Conductivity reliability of dimming stack - ○ ○ △1 △1 Gap control - ○○ ○○ ○ ○

[0159] [Table 3] Example 9 Example 10 Example 11 Example 12 Colored resin particles Colorant carbon black weight% - - - - Titanium Black weight% - - - - Azo pigments weight% 0.1 1.0 4.8 4.8 resin particles styrene weight% - - - - Divinylbenzene weight% 30.0 29.7 28.6 28.6 Polytetramethylene glycol diacrylate weight% 69.9 69.3 66.7 66.7 Pentaerythritol tetraacrylate weight% - - - - Average particle size μm 20 20 20 20 Content of particles with a diameter more than 1.2 times the average particle size ppm 10 10 100 1000 CV value of particle size % 4 4 4 4 proportion - 1.17 1.17 1.17 1.17 brightness L 0* - 27.42 24.73 22.34 22.34 L 540* - 51.26 31.94 27.88 27.88 L 0* / L 540* - 0.53 0.77 0.80 0.80 20% K value N / mm 2 1270 1270 1450 1450 Volume resistivity Ω·cm 1.0×10 12 1.0×10 12 1.0×10 12 1.0×10 12 Evaluation The presence or absence of colorant - have have have have Light leakage suppression - △ ○ ○○ ○○ Inhibitory properties of colored resin particles - ○○ ○○ ○○ ○○ Conductivity reliability of dimming stack - ○ ○ ○ ○ Gap control - ○○ ○○ ○ △1

[0160] [Table 4] Example 13 Example 14 Example 15 Comparative example 1 Colored resin particles or resin particles Colorant carbon black weight% - 4.8 20.0 - Titanium Black weight% - - - - Azo pigments weight% 4.8 - - - resin particles styrene weight% - - - - Divinylbenzene weight% 28.6 38.1 40.0 50.0 Polytetramethylene glycol diacrylate weight% 66.7 - - - Pentaerythritol tetraacrylate weight% - 57.1 40.0 50.0 Average particle size μm 20 20 20 20 Content of particles with a diameter more than 1.2 times the average particle size ppm 10000 10 10 10 CV value of particle size % 4 4 4 4 proportion - 1.17 1.16 1.19 1.19 brightness L 0* - 22.34 21.39 15.76 95 L 540* - 27.88 22.67 16.21 95 L 0* / L 540* - 0.80 0.94 0.97 1.00 20% K value N / mm 2 1450 6060 4700 4400 Volume resistivity Ω·cm 1.0×10 12 1.0×10 11 1.0×10⁹ 1.0×10 15 evaluate The presence or absence of colorant - have have have none Light leakage suppression - ○○ ○○ ○○ × Inhibitory properties of colored resin particles - ○ △2 △1 - Conductivity reliability of dimming stack - ○ △1 △2 - Gap control - △2 ○○ ○○ -

[0161] Furthermore, since Comparative Example 1 does not contain colorants, the following aspects were not evaluated: (7) the ability to inhibit the destruction of coloring resin particles, (8) the conductivity reliability of the dimming laminate, and (9) the gap control.

[0162] 1: Colored resin particles 2: First substrate 3: Second substrate 4,5: Dimming layer 4A: Liquid Crystal Capsule 4B: Adhesive 5A: Light-adjusted droplets of suspension 5Aa: Dispersion medium 5Ab: Light Adjustment Particles 5B: Resin matrix 11: PDLC method for dimming stacking 21: SPD method of dimming stacking

Claims

1. A coloring resin particle comprising resin particles and a coloring agent, wherein the 20% K value of the coloring resin particle is 100 N / mm² to 3000 N / mm², and when the luminance of the coloring resin particle before light irradiation and the coloring resin particle after light irradiation with a cumulative light intensity of 540 MJ / m² are measured according to the L*a*b* color system of JIS Z8781-4:2013, the luminance L0* of the coloring resin particle before light irradiation is 0 to 60, and the ratio of the luminance L0* of the coloring resin particle before light irradiation to the luminance L540* of the coloring resin particle after light irradiation is 0.3 or more.

2. The colored resin particles of claim 1 have a volume resistivity of 1.0 × 10⁹ Ω・cm or higher.

3. The colored resin particles of request item 1 or 2 have an average particle size of more than 1 μm and less than 150 μm.

4. The colored resin particles of claim 1 or 2 do not contain particles having a particle size of more than 1.2 times the average particle size, or contain less than 1000 ppm particles having a particle size of more than 1.2 times the average particle size.

5. The coloring resin particles of request item 1 or 2 have a particle size CV value of 10% or less.

6. The colored resin particles as claimed in claim 1 or 2, wherein the colorant comprises organic black pigment, titanium black particles, or carbon black particles.

7. The colored resin particles of claim 1 or 2, wherein the colored resin particles contain the aforementioned colorant in an amount of less than 20% by weight out of 100% by weight of the colored resin particles.

8. The specific gravity of the colored resin particles, as requested in item 1 or 2, is 1.5 or less.

9. The colored resin particles of claim 1 or 2, wherein the colored resin particles contain components derived from polyfunctional (meth)acrylate compounds.

10. The colored resin particles of claim 1 or 2, wherein the colored resin particles contain at least 50% by weight of a component derived from a polyfunctional (meth)acrylate compound in 100% by weight of the colored resin particles.

11. The colored resin particles of claim 1 or 2, used as spacers.

12. The colored resin particles of claim 11 are used as spacers in a light-adjusting laminate.

13. A dimming laminate comprising: a first substrate, a second substrate, and a dimming layer disposed between the first substrate and the second substrate, wherein the dimming layer comprises colored resin particles as claimed in any one of claims 1 to 12.

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