JP2010195891A - Multilayer structure spherical particle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multilayer structure spherical particle capable of reflecting selectively light in specific wavelengths in a broad range although conventional particles cannot reflect selectively light in specific wavelengths in a broad range. <P>SOLUTION: The multilayer structure spherical particle has a structure having as a core a central layer (L0) containing a norbornene derivative as an essential structural monomer and having a weight-average molecular weight of ≥10,000, and two or more layers (L1) to (Ln) (n is an integer ≥2) laminated concentrically on the center of the core. Differences in refractive index (25°C) between adjacent layers of (L0) to (Ln) are all 0.01 to 1.5. At least one layer of the layers (L0) to (Ln) is a metal oxide layer (M). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to multilayer structured spherical particles.

  Conventionally, as a particle having a multi-layer structure, for example, a multi-layer structure in which two or more polymer layers satisfying a relationship in which the difference in interfacial tension with respect to water exceeds 0.1 (mN / m) is laminated concentrically with four or more layers. A multilayer structure polymer particle (for example, see Patent Document 2) composed of molecular fine particles (for example, see Patent Document 1), a crosslinked methyl methacrylate layer, a crosslinked elastic alkyl acrylate layer, and a hard thermoplastic methyl methacrylate layer is disclosed. Further, spherical titania particles are used as core particles, and a structure in which two or more layers are stacked concentrically with respect to the center of the core, and the difference in refractive index between adjacent layers is 0.01 to 1.5. A certain multilayer structure spherical particle (the composition of the layer is crosslinked polystyrene-silica, polytetrafluoroethylene-titania, alumina-titania. The number of layers is 3 to 23) (for example, refer to Patent Document 3) and the like. .

JP 2004-35785 A JP 2004-352837 A JP 2008-230218 A

However, conventional particles have a problem that light of a specific wavelength cannot be selectively reflected over a wide range.
Then, an object of this invention is to provide the multilayer structure spherical particle which can selectively reflect the light of the specific wavelength of a wide range.

The inventors of the present invention have reached the present invention as a result of studies to achieve the above object.
That is, in the present invention, a core layer (L0) made of a resin having a norbornene derivative as an essential constituent monomer and a weight average molecular weight of 10,000 or more is used as a core, and two or more layers are formed concentrically with respect to the center of the core. It has a structure in which layers (L1) to (Ln) (n is an integer of 2 or more) are laminated, and all of the refractive index differences (25 ° C.) of adjacent layers in (L0) to (Ln) are 0.01 to Multilayer structured spherical particles in which at least one of the layers (L1) to (Ln) is a metal oxide layer (M) and at least one of the other layers is a resin layer (R) It is.

  The multilayer structured spherical particle of the present invention can selectively reflect light of a specific wavelength over a wide range {excellent in the function of extracting light of a specific wavelength by light interference. }. Therefore, the multilayer structured spherical particles of the present invention can be used as a colorant having a high color purity.

  The multilayer structured particle of the present invention has a central layer (L0) containing a resin having a norbornene derivative as an essential constituent monomer and a weight average molecular weight of 10,000 or more as a core, and two layers concentrically with the center of the core. It has a structure in which the above layers (L1) to (Ln) (n is an integer of 2 or more) are laminated, and all of the refractive index differences (25 ° C.) of adjacent layers in (L0) to (Ln) are 0. A multilayer structure in which at least one of the layers (L1) to (Ln) is a metal oxide layer (M) and at least one of the other layers is a resin layer (R) Spherical particles.

  The weight average molecular weight of the resin having the norbornene derivative as an essential constituent monomer is preferably 10,000 to 1,000,000, more preferably 100,000 to 900,000, particularly from the viewpoint of strength and melt viscosity. Preferably it is 300,000-800,000.

  Examples of resins having norbornene derivatives as essential constituent monomers include ring-opening polymers of norbornene derivatives, ring-opening copolymers of norbornene derivatives and other monomers capable of ring-opening copolymerization with these derivatives, and polymers of these polymers. Hydride, addition polymer of norbornene derivative, addition copolymer of norbornene derivative and other monomer copolymerizable with this monomer, transannular polymer of norbornene derivative and other copolymerizable with norbornene derivative and this monomer Examples include transannular polymers with monomers.

Norbornene derivatives are norbornene, derivatives obtained by adding conjugated dienes such as butadiene to norbornene and these are methyl group, ethyl group, propyl group, methoxy group, phenyl group, benzyl group, amino group, vinyl group, chloro group, fluoro group , And a compound substituted with a substituent such as a methylidene group or an ethylidene group. As norbornene and norbornene substituted with a substituent, norbornene, 1-methylnorbornene, 5-methylnorbornene, 7-methylnorbornene, 5,6-dimethylnorbornene, 5,5,6-trimethylnorbornene, 5-ethylnorbornene, 5-propylnorbornene, 5-methoxynorbornene, 5-phenylnorbornene, 5-benzylnorbornene, 5-dimethylaminonorbornene, 5-vinylnorbornene, 5-chloronorbornene, 5-fluoronorbornene, 5-methylidenenorbornene, 5-ethylidene Norbornene, 5-methylidene norbornene, etc.). Examples of the derivative in which norbornene is added to the compound having at least one double bond include dicyclopentadiene, metatetrahydrofluorene, and tetracyclododecene.
The norbornene derivative is preferably norbornene and norbornene substituted with a substituent from the viewpoint of reactivity, more preferably 5-methylnorbornene, 5-ethylnorbornene, 5-propylnorbornene, 5,6-dimethylnorbornene, 1- Methylnorbornene, 7-methylnorbornene, 5,5,6-trimethylnorbornene, 5-phenylnorbornene, 5-benzylnorbornene, 5-ethylidenenorbornene, 5-methylidenenorbornene and 5-vinylnorbornene, and more preferably 5- Ethylidene norbornene, 5-methylidene norbornene and 5-vinylnorbornene.

Examples of the monomer capable of ring-opening copolymerization with a norbornene derivative include monocyclic cyclic olefin monomers (having 3 to 20 carbon atoms, such as cyclohexene, cycloheptene, and cyclooctene).
Monomers that can be copolymerized with norbornene derivatives include α-olefins (having 2 to 20 carbon atoms, such as ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-hexene, Octene, 1-decene, 1-dodecene), cycloolefin (3 to 20 carbon atoms such as cyclobutene, cyclopentene), non-conjugated diene (5 to 20 carbon atoms such as 1,4-hexadiene, 4-methyl-1 , 4-hexadiene), aromatic olefins (having 8 to 20 carbon atoms, such as styrene, divinylbenzene, diisopropenylbenzene, α-methylstyrene, p-methylstyrene), and derivatives thereof.

  Examples of monomers capable of transannular polymerization with a norbornene derivative include α-olefins (having 2 to 20 carbon atoms, such as ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-hexene, Octene, 1-decene, 1-dodecene), cycloolefin (3 to 20 carbon atoms such as cyclobutene, cyclopentene), non-conjugated diene (5 to 20 carbon atoms such as 1,4-hexadiene, 4-methyl-1 , 4-hexadiene), aromatic olefins (having 8 to 20 carbon atoms, such as styrene, divinylbenzene, diisopropenylbenzene, α-methylstyrene, p-methylstyrene), and derivatives thereof.

  As a resin having a norbornene derivative as an essential constituent monomer, from the viewpoint of optical properties, an addition polymer of norbornene and ethylene, a transannular copolymer of methylidene norbornene and styrene, a transannular polymer of methylidene norbornene and ethylene A transannular polymer of ethylidene norbornene and ethylene and a transannular copolymer of ethylidene norbornene and styrene are preferable.

<Multilayer structured spherical particles>
As long as the central layer (L0) constitutes the core, the outer shape is not limited, but from the viewpoint of optical properties, it is preferably a spherical particle having an average circularity of 0.96 to 1, more preferably an average circular shape. Spherical particles having a degree of 0.97 to 1, particularly preferably spherical particles having an average circularity of 0.98 to 1.
The cross-sectional area of the central layer is measured by using a transmission electron microscope (TEM) to measure the cross-section of these particles by solidifying the core spherical particles or multi-layered spherical particles with a resin and cutting them with a diamond cutter or the like. Can be sought.
The average circularity is calculated by calculating a circumferential distance (r1) in a perfect circle having the same area as the “maximum sectional area” of the cross-sectional area of the particle, and calculating the circumferential distance (r1) in “maximum cross-sectional area”. The value divided by “circumferential distance (r2)” is obtained for at least 1,000 particles, and is an arithmetic average value of these values.
The “maximum cross-sectional area” is obtained by subjecting the sample dispersion to a narrow gap and irradiating light from a direction perpendicular to the flow direction, and image-processing the resulting shadow.
The “actually measured circumferential distance (r2)” is obtained from the image processing data obtained when the “maximum cross-sectional area” is obtained.

  All the layers (L1) to (Ln) are stacked concentrically with respect to the center of the core. Further, the layers (L1) to (Ln) are a total of 2 or more layers, preferably 3 layers or more from the viewpoint of selective reflection of light of a specific wavelength in a wide range, more preferably 4 layers or more, and further Preferably it is 5 layers or more, Especially preferably, it is 6 layers or more, Most preferably, it is 7 layers or more. On the other hand, from the viewpoint of production and the like, 30 layers or less are preferable, more preferably 25 layers or less, next more preferably 20 layers or less, and most preferably 10 layers or less.

  N of the layer (Ln) corresponds to each layer and is an integer of 2 or more. The layer adjacent to the central layer (L0) is L1, the layer adjacent to L1 is L2, and n increases toward the outside. That is, the layer (L1) is laminated on the surface of the central layer (L0), the layer (L2) is laminated on the surface of the layer (L1), and the layers (L3), (L4),. The

  In all the layers of the central layer (L0) and the layers (L1) to (Ln), all the refractive index differences (25 ° C.) of adjacent layers are 0.01 to 1.5, preferably 0.05. To 1.48, more preferably 0.1 to 1.46, then more preferably 0.2 to 1.44, especially 0.5 to 1.48, most preferably 1-1.42. Within this range, selective reflection of light in a wide range of specific wavelengths is further improved. If it is less than the lower limit value, it will be difficult to sufficiently reflect or interfere with light, while if it exceeds the upper limit value, it will be difficult to obtain raw materials for producing multilayer structured particles.

The refractive index (25 ° C.) is the same as that of one layer among the layers having the thickness v2 {the same material as the central layer (L0) or (L1) to (Ln) on the base film (thickness v1) having a refractive index of a1. After forming the material layer} and obtaining the laminated film, the refractive index (W) of the laminated film is measured, and the refractive index (a2) of the layer (L0) or (L1) to (Ln) is obtained from the following formula. .
a2 = [W− (a1 · v1 / (v1 + v2))] × [(v1 + v2) / v2]

  The thickness (μm) of each of the layers (L1) to (Ln) is preferably from 0.01 to 1, more preferably from 0.01 to 0, from the viewpoint of selective reflection of light in a wide range of specific wavelengths. .2, particularly preferably 0.02 to 0.1, most preferably 0.06 to 0.1.

The thickness (μm) of the center layer (L0) is preferably 0.05 to 3 and more preferably 0.1 to 2.8 from the viewpoint of ease of manufacture.
The thickness of the center layer (L0) means an average distance from the center of the core forming the center layer (L0) to the center layer surface.

  The thickness of the central layer (L0) and the layers (L1) to (Ln) is determined by solidifying the multilayer structure spherical particles with a resin and cutting with a diamond cutter or the like, and cross-sectioning the multilayer structure spherical particles with a transmission electron microscope (Transmission Electron Microscope). : TEM).

The standard deviation of the thickness of at least one of the layers (L1) to (Ln) is preferably 0.1% to 30%, more preferably 0.5% to 20%, from the viewpoint of uniform interference of light. Yes, most preferably from 1% to 10%.
Since the standard deviation can be easily set within this range by forming a layer by the atomic layer deposition method, the atomic deposition method is preferred as the layer forming method.

From the viewpoint of color purity, the volume average particle diameter (μm) of the multilayer structured spherical particles of the present invention is preferably 0.1 to 20, more preferably 0.5 to 15, and particularly preferably 1 to 10.
The volume average particle diameter can be measured by dispersing a measurement sample in water and using a light scattering type particle size distribution measuring instrument {for example, LA-950 manufactured by Horiba, Ltd.).

  Based on the volume of the multilayer structured spherical particles, the volume ratio of the central layer (L0) is preferably 5 to 98% by volume, more preferably 10 to 95% by volume, and particularly preferably 82 to 95% from the viewpoint of light reflection. %.

The volume of the central layer (L0) is obtained by solidifying the multilayer structure spherical particles with a resin, cutting with a diamond cutter or the like, and measuring the cross section of the multilayer structure spherical particles using a transmission electron microscope (TEM). Can do.
That is, the radius (r) in a perfect circle having the same area as the “maximum cross-sectional area” of the particles obtained in the same manner as in calculating the average circularity is calculated, and at least 1,000 of the radii (r) are calculated. Then, the arithmetic average value of the radius, which is the arithmetic average value of these values, is obtained, and the volume of the true sphere is calculated from the arithmetic average value of the radius assuming that the central layer is a true sphere.

Of the layers (L1) to (Ln), at least one of them may be a metal oxide layer (M), and the metal oxide layer (M) and another layer {for example, a resin layer (R)} May be mixed.
When the other layer {for example, the resin layer (R)} and the metal oxide layer (M) are mixed, the other layer {for example, the resin layer (R)} and the metal oxide layer (M) It is preferable to have an alternately stacked structure.

  The central layer (L0) is made of a resin having a norbornene derivative as an essential constituent monomer.

  Examples of the metal oxide that can constitute the metal oxide layer (M) include silica, alumina, magnesium oxide, zinc oxide, titanium oxide, zirconium oxide, antimony oxide, and natural products containing these metal oxides. Can be mentioned. Examples of natural products include talc, kaolin clay, montmorillonite, mica, bentonite, rholite clay, and chrysotile.

  Of these, at least one selected from the group consisting of silica, alumina, magnesium oxide, zinc oxide and titanium oxide is preferable from the viewpoint of ease of manufacture and refractive index, and more preferably a group consisting of silica, alumina and titanium oxide. It is at least 1 sort chosen from more.

  Other layers include a resin layer (R) and a metal nitride layer. Among these, the resin layer (R) is preferable from the viewpoint of ease of production.

  Monomers that can form the resin layer (R) include those that are not colored and have film-forming properties, and from the viewpoints of transparency and refractive index, norbornene derivatives having a halogenated silyl group are preferred. That is, as the resin constituting the resin layer (R), a resin formed from a norbornene derivative having a halogenated silyl group is preferable.

The norbornene derivative having a halogenated silyl group is not particularly limited as long as it is a norbornene derivative having a halogenated silyl group, and specific examples thereof include 5-ethylidene norbornene, 5-methylidene norbornene and 5-vinylnorbornene. Examples thereof include a monomer in which a halogenated silyl group (such as a trichlorosilyl group) is introduced into a norbornene derivative having two double bonds by a hydrosilylation reaction. Specifically, this hydrosilylation reaction can be performed by adding trichlorosilane to 5-ethylidene norbornene or the like. In addition, a norbornene derivative means the compound mentioned above.
As the halogen, chlorine is preferable because it is easily available.

  The norbornene derivative having a halogenated silyl group is preferably a compound obtained by adding a trichlorosilyl group to methylidene norbornene or a compound obtained by adding a trichlorosilyl group to ethylidene norbornene from the viewpoint of reactivity.

The multilayer structure spherical particles of the present invention are not limited in the outer shape, but are preferably spherical particles having an average circularity of 0.96 to 1, and more preferably an average circularity of 0.97 to 1, from the viewpoint of optical properties. Spherical particles, particularly preferably spherical particles having an average circularity of 0.98 to 1. The outer shape of the multilayer structured spherical particle of the present invention greatly depends on the outer shape of the central layer (L0).
In addition, the average circularity of the multilayer structure spherical particles is obtained in the same manner as the average circularity of the central layer (L0).

  In a multilayer structure with a layer thickness of 0.02 to 0.1 μm, the light reflected by a certain layer interferes with the light reflected by the inner layer or the outer layer, so the layer thickness and refractive index The wavelength light corresponding to 1 appears colored (shows structural color). Various structural colors can be seen depending on the viewing angle. When the multilayer structured spherical particles are spherical particles, the viewing angle is constant, and one color (single light) is seen. In addition, the greater the difference in refractive index between adjacent layers, and the greater the number of layers, the greater the reflection efficiency {the greater the amount of reflected light with respect to incident light}, and the stronger structural color is obtained. .

  On the other hand, in a multilayer structure having a layer thickness of 1 to 3 μm, no light interference occurs and light of all wavelengths is reflected. And as the number of layers increases, more efficient light scattering occurs.

  From the viewpoint of optical properties, it is preferable that at least one of the center layer (L0) and the layers (L1) to (Ln) contains the colorant (D). The colorant (D) is preferably at least one selected from the group consisting of dyes, pigments and phosphors from the viewpoints of the purity of color light and color reproducibility.

  As dyes, acid alizarin violet N, acid black, acid blue, acid chrome violet K, acid Fuchsin, acid green, acid orange, acid red, acid violet 6B, Direct yellow, Direct Orenge, Direct Violet, Direct Blue, Direct Green Mordant Yellow, Mordant Orange, Mordant Violet, Mordant Green, Food Yellow 3 and derivatives of these dyes. In addition, other dyes {azo-based, xanthene-based or phthalocyanine-based acidic dyes} can be used, such as CISolvent Blue 44,38, CISolvent Orenge 45, Rhodamine B, Rhodamine 110, 2,7-Naphthalenedisulfonic acid, and these Dye derivatives can also be used.

  As the pigment, a red colorant {C. I. Pigment red 254, C.I. I. Pigment Red 177, etc.}, green colorant {C.I. I. Pigment green 36, C.I. I. Pigment yellow 150 or C.I. I. Pigment Yellow 138 and the like} and blue colorant {C.I. I. Pigment blue 15, C.I. I. Pigment blue 22, C.I. I. Pigment blue 60 and C.I. I. Pigment blue 64 etc.}.

  Phosphors include inorganic phosphors {oxides such as rare earth elements (zinc, cadmium, magnesium, silicon, yttrium, etc.), sulfides, silicates, vanadates, etc.} and organic phosphors {fluorescein, eosin and oils. (Mineral oil) etc.}. The activator is selected from silver, copper, manganese, chromium, europium, zinc, aluminum, lead, phosphorus, arsenic, gold, and the like. The solvent is selected from sodium chloride, potassium chloride, magnesium carbonate, barium chloride and the like.

  When the colorant (D) is contained, the content (% by weight) of the colorant (D) is preferably 0.1 to 10, more preferably 0.5 to 5, based on the weight of the multilayer structured spherical particle. It is.

<Method for producing multi-layered spherical particles>
The center layer (L0) is obtained by a general emulsion polymerization method, suspension polymerization method, miniemulsion method, dispersion polymerization method or the like.

  The multilayer structured spherical particle of the present invention can be produced by stacking two or more layers (Ln) concentrically with the center layer (L0) as a core, and from the viewpoint of optical properties, from the viewpoint of optical properties. It is preferable to manufacture by laminating by a layer deposition method.

  Specifically, the atomic layer deposition method is a method in which a multilayered spherical particle intermediate having a central layer (L0) or a reactive group (a) on the surface is reacted with a gaseous metal compound by heating. After the metal compound layer was formed on the surface of the central layer (L0) or the multilayer structure spherical particle intermediate to obtain the metal compound layer-formed particles, the unreacted gaseous metal compound was removed to form the metal compound layer. Production process of obtaining multilayer structure spherical particle intermediate or multilayer structure spherical particle by reacting particles and water vapor to change metal compound layer to metal oxide layer (M), and / or central layer (L0) or reaction A particle having an organic layer formed by reacting a multilayer particle having a functional group (a) on the surface with a gaseous organic compound by heating to form an organic layer on the surface of the central layer (L0) or the multilayer particle. After that, the unreacted gaseous organic substance is removed, and if necessary, the particles in which the organic layer is formed are reacted with water vapor to give a reactive group (a) to the organic compound layer. It is a manufacturing method including a manufacturing process for obtaining spherical particles.

  In principle, in order to form a layer by the atomic layer deposition method, the surface of the central layer (L0) before the formation and the surface of the multilayer structure spherical particle intermediate have a reactive group (a). is necessary. However, water {a trace amount of water contained in the central layer (L0) and the multilayered spherical particle intermediate or water in the production environment} is adsorbed on these surfaces, thereby forming surfaces having hydroxyl groups on these surfaces. Therefore, even if the central layer (L0) or the multilayer structure spherical particle intermediate itself does not have the reactive group (a), the layer can be formed substantially by the atomic layer deposition method.

  The reactive group (a) is not limited as long as it can react with a gaseous metal compound and / or a gaseous organic compound. From the viewpoint of reactivity, a group having active hydrogen is preferable. Preferred are a hydroxyl group, a carboxy group, an amino group, an isocyanate group, and a chloro group.

  The gaseous metal compound is not particularly limited as long as it reacts with the reactive group (a). From the viewpoint of reactivity, titanium halide {titanium chloride etc.}, alkylaluminum {trimethylaluminum etc.} and halogenated Silicon {silicon chloride etc.} is preferred.

  The gaseous organic compound is not particularly limited as long as it reacts with the reactive group (a). From the viewpoint of reactivity and optical properties, a compound having a silyl halide group is preferable, and a halogenated compound is more preferable. A norbornene derivative having a silyl group (a compound obtained by adding a trichlorosilyl group to ethylidene norbornene) is preferred.

  As the reaction vessel, a heat-resistant / pressure-resistant vessel is preferable, and from the viewpoint of production, a heating device, a gas inlet, and a decompression device are more preferably installed, and a material that does not react with a gaseous metal compound and a gaseous organic compound). Is.

The water content in the reaction vessel is preferably small from the viewpoint of the stability of the metal compound and the organic compound, more preferably 100 ppm or less, and particularly preferably 10 ppm or less.
As reaction temperature (degreeC), 30-500 are preferable.

In order to remove the unreacted metal compound, a method of reducing the pressure in the container, a method of replacing the inside of the container with an inert gas (such as nitrogen gas and helium gas), or the like can be applied.
The reaction temperature (° C.) between the metal compound layer and water vapor is preferably 30 to 500.

In the manufacturing process of the above atomic deposition method, a layer having a thickness of about 0.2 nm is formed per time, and the manufacturing process can be repeated using the same kind of metal compound or organic compound to obtain a target thickness.
Therefore, when applying this manufacturing process, it is preferable to repeat the same manufacturing process several times until it becomes predetermined thickness.

  The multilayer structured spherical particles of the present invention can be applied to display color filters, coating materials {colored paints, matte paints, reflectors / reflective film paints, etc.]. In addition, it can be used as a pigment or dye.

When the multilayer structure spherical particle of the present invention is spherical, it is suitable for a color filter for display. It is also suitable for resin films and coating materials.
The color filter can be produced, for example, by discharging a dispersion liquid in which spherical multi-layered structure spherical particles {5 to 20% by weight}, a binder, and the like are dispersed on a glass substrate with an inkjet nozzle, and then drying.

The resin film is manufactured by (1) a method in which multilayer structure spherical particles are dispersed in a resin solution and cast to form a film, and (2) a method in which multilayer structure spherical particles are dispersed in a monomer and then polymerized. it can.
The content (% by weight) of the multilayer structure spherical particles is preferably 1 to 80, more preferably 5 to 50, based on the total weight of the resin for film and the multilayer structure spherical particles.
Examples of the resin for film include optical resins {for example, polymethyl methacrylate (PMMA), polycarbonate and polyester}, and binder resins {for example, urethane resin, epoxy resin, acrylic resin and polyester}).

  The coating material is obtained by mixing raw materials used in known paints and inks {binders and solvents, etc.} and the multilayer structured spherical particles of the present invention {the multilayer structured spherical particles are not destroyed by shearing stress due to mixing. So be careful. }.

  Hereinafter, although an example and a comparative example explain the present invention further, the present invention is not limited to these. Hereinafter, unless otherwise specified, “%” represents “% by weight” and “parts” represents “parts by weight”.

<Production Example 1>: Production of spherical ethylidene norbornene particles (central layer) 0.1 parts of tin chloride as a Lewis acid was added to 100 parts of a 20% methylene chloride solution of ethylidene norbornene monomer at -10 ° C for 3 hours. A transannular polymer (Mw = 80,000) was obtained by stirring. 100 parts of a toluene solution (concentration 10%) of this ethylidene norbornene polymer, 5 parts of a product name “Eleminol MON-7” manufactured by Sanyo Chemical Industries Ltd. and 10 parts of a 10% CMC (carboxymethylcellulose) aqueous solution as a dispersant. A dispersion containing spherical ethylidene norbornene particles (LB-1) was obtained by shearing with a homogenizer in addition to an aqueous solution dissolved in 100 parts of water. After toluene was distilled off by nitrogen flow, this dispersion was centrifuged (4000 rpm), washed with water, and dried {50 ° C. × 48 hours, smooth air dryer; the same applies hereinafter. }, Spherical ethylidene norbornene particles (LB-1) were obtained {volume average particle size 2.5 μm, average circularity 0.98}.

<Production Example 2>: Production of ethylidene norbornene trichlorosilane adduct (resin layer raw material (r-1)) 100 parts of ethylidene norbornene (a-1) on a glass Kolben equipped with a heating / cooling / stirring device and a reflux condenser. , 500 parts of trichlorosilane (a-2) and 4 parts of azobisisobutyronitrile (a-3) were charged and heated at 80 ° C. for 16 hours.
Then, the resin layer raw material (r-1) was obtained by distilling at 60 degreeC under a normal pressure.

<Production Example 3>: Production of spherical polystyrene particles (central layer) Under a condition of -10 ° C, 0.1 part of tin chloride as Lewis acid was added to 100 parts of a 20% methylene chloride solution of styrene monomer and stirred for 3 hours. As a result, polystyrene (Mw = 80,000) was obtained. 100 parts of a 10% toluene solution of polystyrene is added as a dispersant to an aqueous solution obtained by dissolving 5 parts of “ELEMINOL MON-7” manufactured by Sanyo Kasei Kogyo Co., Ltd. and 10 parts of a 10% CMC aqueous solution in 100 parts of water. Was used to obtain a dispersion containing spherical polystyrene particles (LB-2). After toluene was distilled off by nitrogen flow, this dispersion was centrifuged (4000 rpm), washed with water, and dried {50 ° C. × 48 hours, smooth air dryer; the same applies hereinafter. } To obtain spherical polystyrene particles (LB-2) {volume average particle size 2.4 μm, average circularity 0.98}.

<Production Example 4>: Production of styrene trichlorosilane adduct (resin layer raw material (r-2)) A glass Kolben equipped with a heating / cooling / stirring device and a reflux condenser, 100 parts of styrene (a-4), tri 500 parts of chlorosilane (a-2) and 4 parts of azobisisobutyronitrile (a-3) were charged and heated at 80 ° C. for 16 hours.
Then, the resin layer raw material (r-2) was obtained by distilling at 60 degreeC under a normal pressure.

<Production Example 5>: Production of titania spherical particles (center layer) 200 parts of titanium tetraisopropoxide, 750 parts of methyl ethyl ketone, and 7 parts of polyvinyl pyrrolidone (number average molecular weight 40000) were uniformly mixed, then heated to 50 ° C., 1 2 parts of an aqueous ammonia solution was added dropwise over 1 hour. After dropping, the mixture was heated to 80 ° C. and reacted for 8 hours to obtain a dispersion containing spherical titania particles (LB-3). Spherical titania particles (LB-3) are centrifuged {4000 rpm), washed with water, dried {50 ° C x 48 hours, smooth air dryer; and so on. } Were obtained by {volume average particle size 2.5 μm, average circularity 0.98}.

<Production Example 6>
(1) 50 parts of spherical ethylidene norbornene particles (LB-1) were put in a container that can be decompressed, sealed, and this container was heated to 100 ° C., decompressed to −0.2 MPa, and held for 20 minutes.
(2) Subsequently, the temperature was maintained at 100 ° C., the pressure in the container was set to −0.05 MPa using nitrogen gas (purity: 99.999%), and titania chloride was charged into the container until the pressure became 0 MPa. After holding at 100 ° C. for 1 minute, the pressure was again reduced to −0.2 MPa. Subsequently, the temperature was maintained at 100 ° C., the pressure was reduced to 0 MPa with nitrogen gas, the pressure was reduced to −0.2 MPa, the pressure was reduced to −0.05 MPa with nitrogen gas, and water vapor was charged into the container until the pressure became 0 MPa. After maintaining at 100 ° C. for 5 minutes, the pressure was again reduced to −0.2 MPa.
(3) The operation of (2) is further repeated 135 times, cooled to 25 ° C., returned to normal pressure, and a two-layer structure spherical particle (LB-4) having an ethylidene norbornene layer-titania layer {volume average particle size 2. 5 μm and an average circularity of 0.98} were obtained.

<Production Example 7>
In production example 6, double-layered spherical particles (LB-) were obtained in the same manner as in Example 1, except that “repeat the operation of (2) 135 times” was changed to “repeat the operation of (2) 165 times”. 5) {volume average particle size 2.5 μm, average circularity 0.98} was obtained.

<Production Example 8>
In Production Example 6, two-layer structured spherical particles (LB) were obtained in the same manner as in Production Example 6, except that “Repeat operation (2) 135 times” was changed to “Repeat operation (2) 190 times”. -6) {Volume average particle diameter 2.6 μm, average circularity 0.98} was obtained.

<Production Example 9>
In the same manner as in Production Example 6, except that “spherical ethylidene norbornene particles (LB-1)” is changed to “spherical polystyrene particles (LB-2)” in Production Example 6, two-layer structured spherical particles (LB-7) ) {Volume average particle size 2.6 μm, average circularity 0.98} was obtained.

<Production Example 10>
Production Example 6 except that “spherical ethylidene norbornene particles (LB-1)” was changed to “spherical titania particles (LB-3)” and “titania chloride” was changed to “trimethylaluminum” in Production Example 6. In the same manner as in Example 6, two-layer structure spherical particles (LB-8) {volume average particle size 2.6 μm, average circularity 0.98} were obtained.

<Example 1>
In Production Example 6, “spherical ethylidene norbornene particles (LB-1)” was changed to “two-layer structure spherical particles (LB-4)”, and “titania chloride” was changed to “resin layer raw material (r-1)”. In the same manner as in Production Example 6 except that the three-layer structure spherical particles (LB-9) having an ethylidene norbornene layer-titania layer-ethylidene norbornene layer {volume average particle size 2.6 μm, average circularity 0. 98}.

<Example 2>
A four-layered spherical particle was obtained in the same manner as in Production Example 6 except that “spherical titania particle (LB-1)” was changed to “three-layered spherical particle (LB-13)” in Production Example 6. . Furthermore, in Production Example 6, “spherical titania particles (LB-1)” was changed to “four-layer structure spherical particles”, and “titania chloride” was changed to “resin layer raw material (r-1)”. In the same manner as in Production Example 6, spherical particles having a five-layer structure were obtained. Subsequently, in Production Example 6, “spherical titania particles (LB-1)” were changed to “obtained multilayer structure spherical particles”, and “titania chloride” and “resin layer raw material (r-1)” By repeating the same operations as in Production Example 6 except that they are alternately changed, the ten-layer structure spherical particles (LB-10) in which the titania layer and the ethylidene norbornene layer are alternately formed in the center layer of the ethylidene norbornene layer are obtained. Obtained {volume average particle size 3.1 μm, average circularity 0.98}.

<Example 3>
In Production Example 6, “spherical ethylidene norbornene particles (LB-1)” were changed to “two-layer structure spherical particles (LB-5)”, and “titania chloride” was changed to “resin layer raw material (r-1)”. Ethylidene norbornene layer-titania layer-ethylidene in the same manner as in Production Example 6, except that the change was made and "Repeat operation (2) 135 times" was changed to "Repeat operation (2) 165 times". Three-layer structure spherical particles (LB-11) having a norbornene layer (volume average particle size 2.6 μm, average circularity 0.98) were obtained.

<Example 4>
In Production Example 6, “spherical ethylidene norbornene particles (LB-1)” were changed to “two-layer structure spherical particles (LB-6)”, and “titania chloride” was changed to “resin layer raw material (r-1)”. Ethylidene norbornene layer-titania layer-ethylidene in the same manner as in Production Example 6 except that the change was made and "Repeat operation (2) 135 times" was changed to "Repeat operation (2) 190 times". Three-layer structure spherical particles having a norbornene layer (LB-12) {volume average particle diameter of 2.7 μm, average circularity of 0.98} were obtained.

<Comparative Example 1>
In Production Example 6, “spherical ethylidene norbornene particles (LB-1)” were changed to “two-layer structure spherical particles (LB-7)”, and “titania chloride” was changed to “resin layer raw material (r-2)”. Except for the change, in the same manner as in Production Example 6, three-layer structure spherical particles (LB-13) having a styrene layer-titania layer-styrene layer {volume average particle size 2.5 μm, average circularity 0.98} Obtained.

<Comparative example 2>
Titania layer-alumina layer-titania in the same manner as in Production Example 6, except that “spherical ethylidene norbornene particles (LB-1)” was changed to “two-layer structured spherical particles (LB-8)” in Production Example 6. Three-layer structure spherical particles (LB-14) having a layer {volume average particle size 2.6 μm, average circularity 0.98} were obtained.

<Comparative Example 3>
Manufacturing Example 6 except that “spherical titania particles (LB-1)” were changed to “three-layer structure spherical particles (LB-14)” and “titania chloride” was changed to “trimethylaluminum”. In the same manner as in Example 6, spherical particles having a four-layer structure were obtained. Furthermore, a 5-layer structured spherical particle was obtained in the same manner as in Production Example 6 except that “spherical titania particle (LB-1)” was changed to “4-layer structured spherical particle” in Production Example 6. Subsequently, in Production Example 6, “spherical titania particles (LB-1)” were changed to “obtained multilayer structure spherical particles”, and “titania chloride” and “trimethylaluminum” were alternately changed. The same operation as in Production Example 6 was repeated to obtain 10-layer structured spherical particles (LB-15) in which alumina layers and titania layers were alternately formed in the central layer of the titania layer {volume average particle size 3 .1 μm, average circularity 0.98}.

  About the multilayer structure spherical particles (LB-9) to (LB-15) obtained in Examples 1 to 4 and Comparative Examples 1 to 3, the number of layers (n), volume average particle diameter, average circularity, thickness of each layer Table 1 shows the average layer thickness, the volume ratio of the central layer (L0), the refractive index of each layer, and the refractive index difference.

The volume average particle diameter, the average circularity, the thickness of each layer, the average layer thickness, the number of layers (n) and the refractive index were measured by the following methods.
(1) Evaluation of volume average particle diameter and average circularity 1 part of multilayer structure spherical particles, 1 part of sodium dodecylbenzenesulfonate and 98 parts of ion-exchanged water were mixed, and an ultrasonic wave was irradiated for 30 minutes to prepare a dispersion. . The volume average particle diameter and average circularity of this dispersion were measured with a flow type particle image analyzer [manufactured by Sysmex Corporation: FPIA-3000].

(2) Measurement of average layer thickness and number of layers (n) 50 parts of epoxy resin with 10 parts of multilayer structure spherical particles {Epicoat 828, Japan Epoxy Resin Co., Ltd., "Epicoat" is Resolution Research Netherland Is a registered trademark. }, And 0.4 part of “SA-102” manufactured by Sun Apro Co., Ltd. was added as a thermosetting accelerator. After heat-curing at 90 degrees, the cured body was cut with a microcutter, and the cross section was taken with a transmission electron microscope. Observation with (TEM), the thickness of 10 points per layer was measured, and this average value was calculated.
The number of layers (n) was confirmed by observing the cross section.

(3) Measurement of Refractive Index of Each Layer In the case of a resin layer, a measurement sample was prepared by applying a resin solution with an applicator. On the other hand, in the case of the metal oxide layer, a measurement sample was prepared by a sol-gel method.
The refractive index was measured at 25 ° C. using an Abbe refractometer [manufactured by Atago Co., Ltd .: NAR-4T].

  The multilayer structure spherical particles obtained in Examples 1 to 4 and Comparative Examples 1 to 3 were evaluated for color developability, wavelength of reflected light, and reflectance by the following methods. The results are shown in Table 2. Further, the spherical particles obtained in Production Examples 1 and 3 and Production Examples 5 to 10 were evaluated in the same manner. As a result, all the particles were not colored and there was no peak top.

<Color development>
Polyvinyl alcohol [PVA205: manufactured by Kuraray Co., Ltd.] 13 parts, polyvinylpyrrolidone [PVP-K30: manufactured by Gokyo Sangyo Co., Ltd.] 6 parts, methanol 173 parts, water 211.4 parts, evaluation sample {multilayered structure spherical resin particles or for comparison Particles} 15 parts were mixed and irradiated with ultrasonic waves for 1 hour to prepare a dispersion. This dispersion was applied on a 50 mm × 50 mm glass substrate with an applicator so that the film thickness was 20 μm, and dried at 80 ° C. for 4 hours to obtain a treated substrate.
The light from the white LED was irradiated from the front surface of the processing substrate, and the light reflected from the processing substrate was visually confirmed.

<Wavelength and reflectance of reflected light>
Using a UV-visible spectrophotometer [manufactured by Shimadzu Corporation: UV-2400PC], the wavelength that reflects the treated substrate was measured, and the wavelength having the peak top was taken as the wavelength of the reflected light, and the reflectance was evaluated.

  The multilayer structure spherical particles of the present invention have sufficient color developability even in a three-layer structure, and have a higher reflectance than the comparative example. Further, the 10-layer structure exhibited a reflectance of almost 100%, and a clear structural color was obtained.

  The multilayer structured spherical particles of the present invention are extremely useful as a colorant for use in display color filters, resin films, coating materials {colored paints, matte paints, etc.}. In addition, it can be used as a pigment or dye.

Claims (3)

A core layer (L0) made of a resin having a norbornene derivative as an essential constituent monomer and a weight average molecular weight of 10,000 or more is used as a core, and two or more layers (L1) to (concentration) are concentrically with the center of the core. Ln) (n is an integer of 2 or more), and the refractive index difference (25 ° C.) of adjacent layers in (L0) to (Ln) is 0.01 to 1.5, Multilayer structured spherical particles in which at least one of the layers (L1) to (Ln) is a metal oxide layer (M). The multilayer structured spherical particle according to claim 1, wherein at least one of the layers (L1) to (Ln) is a resin layer (R). The multilayer structured spherical particle according to claim 1 or 2, wherein at least one of the layers (L1) to (Ln) is a layer formed by an atomic layer deposition method.