JP2014211513A - Optical laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical laminate having a colloidal crystal hardened film reflecting light of a specific wavelength region as a functional layer, and with improved abrasion resistance.SOLUTION: The optical laminate is formed by sequentially stacking a colloidal crystal hardened film layer and then a hard coat layer on a substrate. The colloidal crystal hardened film is a hardened film layer obtained by hardening core-shell particles (A) including a core part and a shell part and a monomer (B). The core-shell particles are periodically arrayed in the hardened film layer with regularity. The core part has an average particle diameter of 50 to 900 nm and a refractive index (n(core)) of the core part satisfying the following expressions (1) and (2). The shell part is a linear polymer having one end covalent-bonded to the core part. n(shell)-n(core)≥0.07...(1) [where n(shell) represents a refractive index of the shell part]. n(B)-n(core)≥0.07...(2) [where n(B) represents a refractive index of the hardened monomer (B)].

Description

  The present disclosure relates to an optical laminate including a color material that exhibits structural color development and a colloidal crystal that can be used as an optical element that reflects light in a specific wavelength range. The optical laminate of the present disclosure is useful for applications in the optical technical field such as optical elements and optical functional materials.

  An aggregate in which monodisperse particles are regularly arranged in three dimensions is called a colloidal crystal. When light enters this colloidal crystal, diffraction and interference occur, and light of a specific wavelength is reflected mainly depending on the periodic structure (Bragg reflection). For example, a colloidal crystal of submicron-sized particles reflects light in the range of ultraviolet light to visible light and further infrared light depending on the particle size. Further, when the wavelength of the reflected light is generated in the visible light region, the color of the colloidal crystal can be visually recognized as the structural color development. Numerous studies have been conducted on colloidal crystals, and development of various optical elements such as photonic crystals and optical functional materials is expected. The colloidal crystal can be applied to, for example, various color materials including paints, inks, cosmetics, optical filters, optical memory materials, display devices, optical switches, sensors, lasers, and the like.

Many examples of colloidal crystal production have already been reported.
For example, a colloidal crystal in a dry state can be obtained by using particles such as polystyrene and silica and growing the crystal by utilizing the accumulation of particles accompanying evaporation of the water-soluble solvent. However, since the particles are collected only by contact, the mechanical strength is very weak, and the colloidal crystal is broken by a slight external force. Then, the manufacturing method which fills the binder which fixes particle | grains in the space | gap between particle | grains is disclosed (for example, refer patent document 1). Also disclosed is a production method in which the shell part fills voids between the particles by using core-shell particles in which the surface of the core part (particles) prepared by two-stage emulsion polymerization is coated with the resin of the shell part. (For example, refer to Patent Document 2).
On the other hand, a method of forming a colloidal crystal in a water-soluble medium, adding a small amount of a water-soluble monomer in a water-soluble solvent, and polymerizing the monomer, thereby fixing the colloidal crystal with a polymer gel. Is disclosed (for example, see Patent Document 3).
Furthermore, by using core-shell particles in which the linear polymer forming the shell part is bonded to the surface of the particle (core part), in the dispersed state in the organic solvent, due to the steric repulsion and osmotic pressure effect of the linear polymer. It is disclosed that aggregation between particles is suppressed and colloidal crystals are formed (see, for example, Patent Document 4). A method of immobilizing colloidal crystals with a polymer gel by containing a small amount of monomer in an organic solvent and polymerizing the monomer is disclosed (see, for example, Patent Document 5).

  In the colloidal crystal described in Patent Document 1, innumerable cracks tend to occur in the coating film during the drying process. This is because the distance between particles gradually decreases in the drying process, but if the shrinkage does not occur uniformly, a part of the crystal breaks and cracks occur. The infinite number of cracks scatter light, and the resulting colloidal crystal has a cloudiness. Moreover, in order to increase the mechanical strength, it is disclosed that a binder is applied after the colloidal crystal is produced. However, since the particles are accumulated only by contact, the colloidal crystal is not coated when the binder is applied. There is a problem that it collapses. Furthermore, even if the voids between the particles are filled with a binder, there is no binder at the contact points between the particles, and the mechanical strength is insufficient. Furthermore, it is difficult to completely fill the gaps between the particles. As the mechanical strength further decreases, the randomly remaining voids cause light scattering, and the white turbidity of the colloidal crystals becomes strong. In the method using the core-shell particles synthesized by the two-stage emulsion polymerization described in Patent Document 2, the member that fills the gap is a polymer having poor fluidity compared to a low-molecular binder, It is difficult to completely fill the gap. Further, since the polymer filling the voids is thermoplastic, the heat resistance, chemical resistance, and mechanical strength of the produced colloidal crystals are not sufficient. For this reason, in order to improve mechanical strength, also when overcoat is given, the material will be very limited.

Since the colloidal crystal described in Patent Document 3 is formed by utilizing electrostatic repulsion due to the surface charge of the particles, it is necessary to use a water-soluble solvent having a high dielectric constant as the dispersion medium. For this reason, it can be immobilized only in a gel state containing a water-soluble solvent.
Moreover, in the colloidal crystal using the core-shell particles described in Patent Documents 4 to 5, when a colloidal crystal is formed using a hydrophobic monomer as a dispersion medium and this monomer is cured (polymerized), a cured film is obtained. It is expected that colloidal crystals can be immobilized. However, there is a problem that the regular arrangement of the particles tends to be lost during polymerization of the monomer, and the optical properties cannot be sufficiently maintained after curing. For this reason, it can be immobilized only in a gel state containing an organic solvent.

  The colloidal crystals fixed as gels containing water-soluble solvents and organic solvents in this way will change the reflection wavelength due to the disruption of the regular arrangement of particles due to the volatilization of the solvent and the distance between particles changing. For this reason, the stability is poor, and it becomes a very big restriction for practical use. Furthermore, since the mechanical strength is poor, practical application to optical elements and optical functional materials has been difficult.

  In order to solve such a problem, the inventors limited the shell part of the core-shell particle in the colloidal crystal and the monomer serving as the binder, thereby allowing the colloid capable of reflecting light in a specific wavelength range. A crystal cured film has been found previously (Patent Document 6). The cured film obtained by this production method is excellent in mechanical strength and solvent resistance, and has excellent long-term stability because there is no volatilization of the solvent, and it can form a cured colloidal crystal by a simple method. There are excellent advantages.

Japanese Patent Laying-Open No. 2005-60654 JP 2009-249527 A JP 2007-29775 A WO2005-108451 WO2003-100139 WO2011-162078

However, the colloidal crystal cured film disclosed in Patent Document 6 has sufficient mechanical strength and temperature stability as an optical element configured inside the apparatus, for example, but has the possibility of contact with a person or an object. When configured on the outer periphery of the apparatus, there is a problem that the wear resistance is insufficient.
Accordingly, an object of the present disclosure is to provide an optical layered body that has a hardened colloidal crystal film that reflects light in a specific wavelength region as a functional layer and has improved wear resistance.

  As a result of intensive studies to achieve the above object, the inventors of the present invention sequentially laminated a hardened layer of a colloidal crystal on a substrate, thereby providing an optical laminate having excellent wear resistance. It was found that can be produced.

The first aspect of the present disclosure is an optical laminate in which a colloidal crystal cured film layer and then a hard coat layer are sequentially laminated on a substrate,
The colloidal crystal cured film (C) is a cured film layer obtained by curing a core-shell particle (A) having a core part and a shell part and a monomer (B),
The core-shell particles are regularly and periodically arranged in the cured film layer,
The average particle diameter of the core part is 50 to 900 nm,
The refractive index (n (core)) of the core portion satisfies the following formulas (1) and (2),
n (shell) -n (core) ≧ 0.07 (1)
[Where n (shell) represents the refractive index of the shell portion]
n (B) -n (core) ≧ 0.07 (2)
[Wherein n (B) represents the refractive index after curing of the monomer (B)]
The shell part is a linear polymer having one end covalently bonded to the core part.

〔式（３）において、Ｒ_１は水素原子又はメチル基であり、ｘは０又は１である〕

〔式（４）において、Ｒ_２は水素原子又はメチル基であり、ｙは1又は2である〕 In the second aspect of the present disclosure, the monomer (B) includes a monomer (B1) represented by the following formula (3) and a monomer (B2) represented by the following formula (4). The content of the monomer (B2) in the monomer (B) is 5 to 70% by weight (however, the total of the monomer (B1) and the monomer (B2) is 100% by weight) %),
The linear polymer is characterized in that it is formed of at least one of styrene and a monomer (S) represented by the following formula (3).

[In Formula (3), R ₁ is a hydrogen atom or a methyl group, and x is 0 or 1]

[In Formula (4), R ₂ is a hydrogen atom or a methyl group, and y is 1 or 2.]

  The third aspect of the present disclosure is characterized in that the hard coat layer is a cured film of epoxy (meth) acrylate or urethane (meth) acrylate.

  A fourth aspect of the present disclosure is characterized in that the epoxy (meth) acrylate has two or more (meth) acryloyl groups in one molecule and has a weight average molecular weight of 400 to 600.

  The fifth aspect of the present disclosure is characterized in that the urethane (meth) acrylate has 3 or more (meth) acryloyl groups in one molecule and a weight average molecular weight of 500 to 4000.

  In the optical layered body of the first aspect, the colloidal crystal layer, which is a functional layer, has a refractive index difference between the core part and the shell part of the core-shell particle (A) and a difference in refractive index between the core part and the monomer (B). By increasing, excellent optical characteristics exhibiting a high reflectance are exhibited. In addition, unlike colloidal crystals in which particles are simply laminated, they are cured colloidal crystals, so that they have mechanical strength and are less susceptible to the influence of coating on the formation of the hard coat layer. Furthermore, since it does not contain a solvent, there is no problem due to the volatilization of the solvent, and heat curing can be performed for forming the hard coat layer. For this reason, a hard-coat layer can be formed easily and abrasion resistance can be improved.

  With the optical layered body of the second side surface, an optical layered body that exhibits substantially the same effect as that of the first side surface can be produced. Furthermore, since the monomer (B1) and the monomer (B2) form a crosslinked structure, thermal properties such as heat resistance of the cured colloidal crystal film layer, mechanical properties such as hardness, and chemical resistance are achieved. And various hard coat layers can be formed. Improvement of the mechanical strength of the intermediate layer also contributes to further improving the wear resistance of the optical multilayer body.

  With the optical layered body of the third side surface, an optical layered body that exhibits substantially the same effect as the first or second side surface can be produced. Furthermore, the influence on the reflectance of the cured colloidal crystal film during the formation of the hard coat layer can be reduced, and the adhesion between the colloidal crystal cured film layer and the hard coat layer can be improved.

  With the optical layered body of the fourth or fifth side surface, an optical layered body that exhibits substantially the same effect as that of the third side surface can be produced. Abrasion resistance can be further improved.

  The optical laminate of the present disclosure is composed of a substrate, a colloidal crystal cured film layer, and a hard coat layer. Hereinafter, each constituent layer will be described in detail.

(1) Substrate As the light-transmitting substrate, those excellent in smoothness, mechanical strength, heat resistance and transparency are preferable. Specifically, thermoplastic resins such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), cellulose triacetate (TAC), polymethyl methacrylate (PMMA), polycarbonate (PC), polyvinyl chloride, polypropylene, polyamide, Examples include amorphous olefin resins having an alicyclic structure such as norbornene-based polymers and cyclic olefin polymers, thermosetting resins such as epoxy resins, urethane resins, thiourethane resins, episulfide resins, and allyl resins, and glass. it can. In optical element and color material applications, when it is desired to absorb transmitted light by a substrate, a colored substrate containing a dye or a pigment can be used.
The base material is preferably used in the form of a film, but a molding material such as a sheet shape or a lens shape having a curvature may be used depending on the form of use.
In order to improve adhesion to the substrate, degreasing treatment with an organic solvent, ultrasonic cleaning treatment, polishing treatment using an abrasive, chemical treatment with an acidic or basic aqueous solution, corona discharge treatment, plasma treatment, UV ozone treatment, Surface treatment such as primer treatment can be performed.

(2) Cured colloidal crystal layer The colloidal crystalline cured layer (C) is a cured layer obtained by curing the core-shell particles (A) and the monomer (B) having a core part and a shell part. The core-shell particles (A) are regularly arranged in the cured film layer. Light in a specific wavelength region is reflected by light diffraction and interference based on this periodic arrangement.

<Core-shell particles (A)>
The core-shell particle (A) has a core part made of particles and a shell part formed of a linear polymer bonded to the surface of the core part.
The core part can be appropriately selected within a range where the refractive index (n (core)) satisfies the following formulas (1) and (2).
n (shell) -n (core) ≧ 0.07 (1)
[Where n (shell) represents the refractive index of the shell portion]
n (B) -n (core) ≧ 0.07 (2)
[Wherein n (B) represents the refractive index after curing of the monomer (B)]
When the refractive index difference is smaller than 0.07 in the formulas (1) and (2), the peak reflectivity of the obtained colloidal crystal cured film is small, and sufficient optical characteristics cannot be obtained. The upper limit of the refractive index difference is not particularly limited, but n (shell) and n (B) are about 1.6, and the refractive index of air is 1.00. The upper limit value is substantially about 0.6. The refractive index of each component is a value measured at 25 ° C. using an Abbe refractometer after preparing a cured film of each component under the same polymerization and curing conditions. The cured film is formed by, for example, applying a coating liquid composed of a monomer and a photopolymerization initiator on a glass substrate so as to have a thickness of 100 μm, and curing the film by irradiation with ultraviolet rays of 1000 mJ / cm ^2. It is produced by peeling off from.

As the core part, inorganic particles, organic polymer particles, or hollow particles containing pores (air) in these particles can be used. The inorganic particles desirably have a low refractive index, and magnesium fluoride, silica, or the like can be used. In particular, the inorganic particles are preferably formed of silica in terms of refractive index, dispersion stability, and cost. As the organic polymer particles, acrylic resin, polyester resin, polycarbonate resin, polyamide resin, urethane resin, fluororesin, polyolefin resin, and copolymers thereof can be used. The organic polymer particles are preferably formed of an acrylic resin because of its low refractive index and easy particle diameter control.
When the core part is formed of an acrylic resin, a (meth) acrylic acid ester monomer or a (meth) acrylamide monomer is used as a monomer that can be used to manufacture the core part. be able to.

  (Meth) acrylic acid ester monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, cyclohexyl (meta ) Acrylate, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, methoxyethylene glycol (meth) acrylate, 2- (meth) acryloyloxyethyl isocyanate, N, N-dimethylamino Ethyl (meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3,3-pentafluoropropyl (meth) acrylate, 2- (perfluorohexyl) ethyl (meth) acryl Such as over doors and the like. Examples of (meth) acrylamide monomers include N, N-dimethyl (meth) acrylamide and N-isopropyl (meth) acrylamide. Among these, it is preferable to use a (meth) acrylic acid ester monomer because of its low refractive index and easy control of the particle diameter. Moreover, the said monomer can be used individually or in combination of 2 or more types according to the objective.

  Furthermore, in order to prevent the core portion from being heated or deformed by an organic solvent, a crosslinkable monomer having two or more polymerizable groups in one molecule may be used in combination. Examples of crosslinkable monomers include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and trimethylolpropane. Examples include tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, triallyl isocyanurate, diallyl phthalate, and divinylbenzene.

  The core part of the core-shell particles (A) has an arithmetic average particle diameter of 50 to 900 nm measured by dynamic light scattering. The average particle size of the core part is preferably 80 to 600 nm, more preferably 100 to 300 nm. When the average particle size of the core part is smaller than 50 nm, it is difficult to suppress the aggregation between the core and shell particles. On the other hand, when the average particle size of the core part is larger than 900 nm, the sedimentation of the core-shell particles is difficult. It is difficult to suppress colloidal crystals. The particle size distribution of the core portion is represented by a CV value [(particle diameter standard deviation / average particle size) × 100 (%)], and the CV value is preferably 25% or less, more preferably 20% or less. It is. The CV value is 0% in the case of monodispersion in which all particle diameters are the same. When the CV value of the core portion is larger than 25%, it is difficult to form a colloidal crystal because the particle diameters are not uniform.

  The linear polymer constituting the shell portion of the core-shell particle (A) does not have a branched structure, and one end thereof is bonded to the core portion by a covalent bond. That is, the linear polymer is grafted on the particle surface of the core part. Since the linear polymer is bonded to the core portion, it does not desorb from the core portion even when dissolved in a monomer or a solvent. Thereby, the dispersion stability of a core-shell particle (A) can be improved. In conventional core-shell particles, the shell part is bonded to the core part by physical adsorption, or is arranged around the core part by forming a three-dimensional network structure so as to surround the core part. . However, in the case of physical adsorption, the shell part is easily detached from the core part, so the shell part does not contribute to the dispersion stability of the core-shell particles. Moreover, when the shell part is arrange | positioned around the core part by the three-dimensional network structure, the dispersion stability of a core-shell particle cannot be ensured.

  The shell part of the core-shell particles (A) can be appropriately selected within a range in which the refractive index (n (core)) satisfies the formula (1). Furthermore, it is preferable that the shell part is formed of at least one of styrene and a monomer (S) represented by the following formula (3). Styrene and monomer (S) can be used alone or in combination as appropriate under the conditions satisfying the above formula (1). Thereby, the cured film which shows the high value of the peak reflectance of the obtained colloidal crystal cured film can be obtained.

〔式（３）において、Ｒ_２は水素原子又はメチル基であり、ｘは０又は１である〕
単量体（Ｓ）は、前記式（３）で表される（メタ）アクリレート化合物のうち異なる複数の化合物を含んでいても良い。単量体（Ｓ）としては、例えば、２−フェニルフェニル（メタ）アクリレート、及び２−フェニルフェノキシエチル（メタ）アクリレートが挙げられる。 The monomer (S) is a (meth) acrylate compound having a biphenyl skeleton represented by the following formula (3).

[In Formula (3), R ₂ is a hydrogen atom or a methyl group, and x is 0 or 1]
The monomer (S) may contain a plurality of different compounds among the (meth) acrylate compounds represented by the formula (3). Examples of the monomer (S) include 2-phenylphenyl (meth) acrylate and 2-phenylphenoxyethyl (meth) acrylate.

  The average particle diameter of the core-shell particles (A) is measured by dynamic light scattering or the like as the sum of twice the thickness of the shell portion and the average particle diameter of the core particles. The average particle diameter of the core-shell particles (A) is 60 to 1,000 nm, preferably 90 to 700 nm, and more preferably 110 to 400 nm. When the average particle size of the core-shell particles (A) is smaller than 60 nm, it becomes difficult to suppress the aggregation of the core-shell particles (A), and the average particle size of the core-shell particles (A) is 1, When it is larger than 000 nm, it becomes difficult to suppress sedimentation of the core-shell particles (A), and it becomes difficult to form colloidal crystals.

  When producing the core-shell particles (A), various known methods can be employed. A method in which a monomer is graft-polymerized from a core portion containing a polymerization initiating group is preferable in that various monomers can be used for a linear polymer. Furthermore, it is preferable to perform graft polymerization from a core part containing a living radical polymerization initiating group in that a high-density linear polymer can be formed and the molecular weight of the linear polymer can be freely designed. For example, it can be produced by the method described in Patent Document 6.

<Monomer (B)>
A monomer (B) can be suitably selected in the range with which the said Formula (2) is satisfy | filled. Furthermore, the monomer (B) is preferably a mixture of the monomer (B1) represented by the formula (3) and the monomer (B2) represented by the following formula (4).
The monomer (B1) is represented by the same formula (3) as the monomer (S), but includes a plurality of different compounds among the (meth) acrylate compounds represented by the formula (3). You can leave.

〔式（４）において、Ｒ_２は水素原子又はメチル基であり、ｙは1又は2である〕 The monomer (B2) is a di (meth) acrylate compound having a fluorene skeleton represented by the following formula (4).

[In Formula (4), R ₂ is a hydrogen atom or a methyl group, and y is 1 or 2.]

The monomer (B2) may contain a plurality of different compounds among the (meth) acrylate compounds represented by the formula (4). Examples of the monomer (B2) include 9,9-bis [4- (2- (meth) acryloyloxyethoxy) phenyl] fluorene, 9,9-bis [4- (2- (2- (meth)). Acryloyloxyethoxy) ethoxy) phenyl] fluorene.

  Furthermore, the monomer (B2) can also use other high refractive index monomers as long as the formula (2) is satisfied. For example, bis (4- (meth) acryloxyphenyl) sulfide, bis (4- (meth) acryloxyethoxyphenyl) sulfide, bis (4- (meth) acryloylthiophenyl) sulfide, and bis (4- (meth) Acryloxyethylthiophenyl) sulfide), 2,2-bis [4- (2- (meth) acryloyloxyethoxy) phenyl] propane, 2,2-bis [4- (2- (2- (meth) acryloyloxy) Ethoxy) ethoxy) phenyl] propane. These can be used alone or in combination of two or more.

  Furthermore, in addition to the above-mentioned components, the monomer (B) is appropriately added with a polyfunctional monomer or oligomer used in the hard coat layer (H) described later within a range satisfying the formula (2). Can do. Furthermore, in order to adjust the viscosity and to improve the adhesion between the hard coat layer (H) and the cured colloidal crystal layer (C), the monofunctional (used in the hard coat layer (H) described later ( A (meth) acrylic acid ester monomer or a monomer having a functional group can be appropriately added within a range that satisfies the above formula (2). The performance can be improved by blending in an amount of 15 parts by weight or less, preferably 5 parts by weight or less, relative to 100 parts by weight of the monomer (B). When the amount is more than 10 parts by weight, the optical properties of the cured colloidal crystal film are not preferable.

  The content of the core-shell particles (A) in the cured film for colloidal crystals is 25 to 65% by weight, preferably 30 to 60% by weight, and more preferably 32 to 50% by weight. However, the total of the core-shell particles (C) and the monomer (B) is 100% by weight. When the amount is less than 25% by weight, colloidal crystallization does not occur because the core-shell particles (A) do not reach the concentrations adjacent to each other. Or even if colloidal crystallization occurs, the ratio of the core-shell particles (A) is small, so that sufficient optical properties cannot be exhibited. On the other hand, when the content of the core-shell particles (A) is more than 65% by weight, the ratio of the core-shell particles (A) is too large, so that the colloidal crystals are cracked or distorted, and the reflectivity is high. Since it becomes low, it is not preferable. The content of the core-shell particles (A) in the cured colloidal crystal film is preferably 30 to 60% by weight. When the content of the core-shell particles (A) is less than 25% by weight, colloidal crystallization does not occur because the core-shell particles (A) do not reach concentrations adjacent to each other. Or even if colloidal crystallization occurs, the ratio of the core-shell particles (A) is small, so that sufficient optical properties cannot be exhibited. On the other hand, when the content of the core-shell particles (A) is more than 65% by weight, the ratio of the core-shell particles (A) is too large, so that the colloidal crystals are cracked or distorted, and the reflectivity is high. Since it becomes low, it is not preferable.

  When the monomer (B) is a mixture of the monomer (B1) represented by the formula (3) and the monomer (B2) represented by the formula (4), the monomer (B The content of the monomer (B2) in) is 5 to 70% by weight, preferably 7 to 60% by weight, and more preferably 10 to 45% by weight. However, the total of the monomer (B1) and the monomer (B2) is 100% by weight. When it is less than 5% by weight, the hard coat composition penetrates into the colloidal crystal cured film in the process of forming the hardcoat layer, and tends to affect the optical properties of the colloidal crystal cured film. When it is more than 70% by mass, the curing shrinkage becomes large and the adhesion tends to be lowered.

  The colloidal crystal cured film can be produced by the method described in Patent Document 6, for example. The composition for colloidal crystal composed of the core-shell particles (A) and the monomer (B) is crystallized on a substrate, and then the monomer (B) is cured by heat or light, The ordered arrangement of the core-shell particles (A) is maintained after curing, and the mechanical strength is increased. In a cured colloidal crystal film, whether or not the regular arrangement of the three-dimensional core-shell particles (A) is maintained after curing is confirmed by a method of confirming a reflection peak from measurement of reflection and transmission spectra, If the peak is in the visible light range, a method of visually confirming the structural coloration can be used. The required optical properties differ depending on the use of the cured colloidal crystal film, but when considering the use of color materials as an example, in order to visually recognize vivid structural colors, the reflectivity of the reflection peak in the reflectance measurement is It is preferable that it is 50% or more. One method for increasing the reflectance of the reflection peak is to increase the film thickness and increase the number of colloidal crystal particles. In the present disclosure, a cured film is defined by polymerizing monomers in the composition in a state where the composition is formed into a film. Therefore, the curing in the present disclosure includes not only curing by the formation of a crosslinked structure of a composition including a monomer having two double bonds but also curing by polymerization of a monomer having one double bond. .

  The thickness of the cured colloidal crystal film is preferably 1 to 100 μm after curing, and more preferably 3 to 50 μm. When the film thickness is thinner than 1 μm, the peak reflectivity of the obtained colloidal crystal cured film becomes small, and sufficient optical characteristics cannot be obtained. On the other hand, when the film thickness is thicker than 100 μm, the haze value tends to increase because cracks and strains are likely to occur.

(3) Hard coat layer The hard coat layer formed on the colloidal crystal cured film improves wear resistance. As a material used for the hard coat layer, a hardened composition of a hard coat composition such as a polyfunctional monomer or oligomer and a reactive silicon compound such as tetraethoxysilane can be used.

  As a polyfunctional monomer or oligomer, a monomer or oligomer having two or more (meth) acryloyl groups in one molecule can be used, and epoxy (meth) acrylate, urethane (meth) acrylate, Polyester (meth) acrylate, polyfunctional (meth) acrylate, etc. can be used. Examples of the epoxy (meth) acrylate include EBECRYL-600, 3701, 3703, 3708 (manufactured by Daicel Cytec Co., Ltd.). Examples of the urethane (meth) acrylate include EBECRYL-220, 5129, 8210, 8701, 8807, 9270 ( As polyester (meth) acrylates, such as Daicel-Cytec Co., Ltd., Shikou UV-1700B, 7650B (Nippon Synthetic Chemical Industry Co., Ltd.), etc., EBECRYL-800, 1830 (Daicel-Cytec Co., Ltd.) As the polyfunctional (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate Relate, dipentaerythritol monohydroxy penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and the like. Furthermore, it is more preferable that the epoxy acrylate has two or more (meth) acryloyl groups in one molecule and has a weight average molecular weight of 400 to 600. Specifically, EBECRYL-600 (manufactured by Daicel-Cytec) is used. As urethane (meth) acrylate, it is more preferable that it has 3 or more (meth) acryloyl groups in one molecule, and the weight average molecular weight is 500-4000. Specifically, purple light UV-1700B (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.), EBECRYL-220-8701 (manufactured by Daicel Cytec Co., Ltd.) and the like can be mentioned. These can be used alone or in combination of two or more.

  In addition to the above components, the hard coat composition containing polyfunctional monomers and oligomers is used to adjust the viscosity of the composition and to improve the adhesion between the hard coat layer and the cured colloidal crystal layer. A monofunctional (meth) acrylic acid ester monomer or a monomer having a functional group can be appropriately added. As (meth) acrylic acid ester monomers, n-butyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2- (perfluorohexyl) ethyl (meth) acrylate, N, N-dimethyl (meth) acrylamide etc. are mentioned. Examples of the functional group of the monomer having a functional group include an alkoxysilyl group, a carboxylic acid group, a hydroxyl group, a phosphoric acid group, an amino group, an epoxy group, an isocyanate group, and a heterocyclic group. As a specific example, 3- (meth) acryloxypropyltrimethoxysilane etc. can be mentioned as a monomer which has an alkoxy silyl group. Examples of the monomer having a carboxylic acid group include 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl phthalic acid, ω-carboxy-polycaprolactone mono (meth) acrylate, and the like. it can. Examples of the monomer having a hydroxyl group include 2-hydroxy-3-phenoxypropyl (meth) acrylate. Examples of the monomer having a phosphate group include 2-((meth) acryloyloxy) ethyl phosphate. Examples of the monomer having an amino group include N, N-dimethylaminoethyl (meth) acrylate. Examples of the monomer having an epoxy group include 4-hydroxybutyl (meth) acrylate glycidyl ether. Examples of the monomer having an isocyanate group include 2- (meth) acryloyloxyethyl isocyanate. Examples of the monomer having a heterocyclic group include tetrahydrofurfuryl (meth) acrylate and (meth) acryloylmorpholine. These can use 1 type (s) or 2 or more types. These monofunctional (meth) acrylic acid ester monomers and monomers having a functional group are preferably 30 parts by weight or less, preferably 100 parts by weight or less with respect to 100 parts by weight of a composition containing a polyfunctional monomer or oligomer. Can improve performance by blending at a ratio of 10 parts by weight or less.

  In addition to the above components, the polyfunctional monomer or oligomer hard coat composition may contain an ultraviolet absorber, thereby improving the weather resistance of the cured colloidal crystal film. Examples of the ultraviolet absorber include inorganic particles and organic ultraviolet absorbers. As the inorganic particles, cerium oxide, zinc oxide, titanium oxide or the like having an average particle diameter of 2 to 100 nm can be used. The blending of the inorganic particles is effective in improving the hardness of the hard coat layer. As an organic ultraviolet absorber, a benzotriazole compound, a benzophenone compound, a hydroxybenzoate compound, or the like can be used. These can use 1 type (s) or 2 or more types. The blending amount of the ultraviolet absorber is preferably 0.1 to 30 parts by weight, more preferably 1 to 10 parts by weight with respect to 100 parts by weight of the hard coat layer. When the blending amount is small, the effect of improving the weather resistance is small, and when it is too large, the wear resistance is lowered or the transparency is lowered, which is not preferable.

The hard coat composition containing a polyfunctional monomer or oligomer can be cured by heat or light. When curing a polyfunctional monomer or oligomer, it is preferable to include a polymerization initiator in order to accelerate curing. As the polymerization initiator, known polymerization initiators such as an azo polymerization initiator, an organic peroxide polymerization initiator, and a photopolymerization initiator can be used. For example, azo-based radical polymerization initiators include azobisisobutyronitrile, azobiscyclohexanecarbonitrile, and organic peroxide-based polymerization initiators include benzoyl peroxide, t-butyl hydroperoxide, dicumyl. Peroxide and the like can be used. As a photopolymerization initiator,
2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one,
1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopro Pan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-hydroxy-1- {4- [4- (2-hydroxy-2-methylpropionyl) ) Benzyl] phenyl} -2-methylpropan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxaside, bis (2,4,6-trimethylbenzoyl) phenyl-phosphine oxide, benzophenone, isopropylthioxanthone, etc. Can be used.

  The amount of the polymerization initiator is preferably 0.1 to 10 parts by weight, more preferably 0.5 to 7 parts by weight with respect to 100 parts by weight of the hard coat composition containing a polyfunctional monomer or oligomer. is there. When the blending amount is small, curing is insufficient and wear resistance is not exhibited. On the other hand, if the amount is too large, the remaining polymerization initiator may cause adverse effects such as a decrease in wear resistance and long-term stability, and a decrease in visible light transmittance.

  In addition to the above components, the hard coat composition containing a polyfunctional monomer or oligomer includes a metal oxide, an infrared absorber, a light stabilizer, an antioxidant, a leveling agent, a surface conditioner, a surfactant, Thickeners, antifoaming agents, colored dyes, fluorescent dyes, pigments (organic pigments, inorganic pigments) and the like can be appropriately blended. Further, any amount of solvent can be added as long as it is dried after film formation in the wet coating method.

  Hard coat compositions containing polyfunctional monomers and oligomers include, for example, spin coating, bar coating, spray coating, dip coating, flow coating, slit coating, doctor blade coating, gravure coating, It can apply | coat on a colloidal crystal cured film (C) by various methods, such as a screen printing method, an inkjet printing method, and a dispenser printing method.

  A hard coat composition containing a polyfunctional monomer or oligomer can form a hard coat layer (H) by being cured by heating or irradiation with active energy rays such as ultraviolet rays, electron beams, and radiations. . Among these, curing can be performed rapidly by performing ultraviolet irradiation. As a light source for ultraviolet irradiation, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, or the like can be used. In this case, heating can be performed to accelerate curing in addition to ultraviolet irradiation. The heating temperature is usually 10 to 150 ° C, preferably 20 to 120 ° C.

The film thickness of the hard coat layer is preferably 0.5 to 10 μm, and more preferably 1 to 5 μm after curing. When the film thickness is thinner than 0.5 μm, the wear resistance is low, and when it is thicker than 10 μm, the hard coat layer is likely to crack.

  Hereinafter, the embodiment will be described more specifically with reference to examples and comparative examples.

[Production Example 1]
<Manufacture of core part>
The core portion was synthesized by two-stage seed emulsion polymerization. As a first step, Aqualon KH-5 (Daiichi Kogyo Seiyaku Co., Ltd., 0.0315 g) was added as a reactive emulsifier to a 500 mL four-necked flask equipped with a condenser, thermometer, stirrer and nitrogen inlet tube. And ion-exchanged water (330 g) were charged. To this was added ethyl methacrylate (EMA, 30.6 g) as a monomer, tert-butyl acrylate (t-BA, 13.5 g) and ethylene glycol dimethacrylate (EGDM, 0.900 g) as a crosslinkable monomer, The mixture was stirred and mixed under a nitrogen stream and heated to 65 ° C. Next, potassium persulfate (0.0180 g) was added as a polymerization initiator to the reaction solution, and the polymerization reaction was performed at 65 ° C. for 5 hours, and then cooled to room temperature.

  Next, as the second step, sodium dodecyl sulfate (0.675 g) as an emulsifier was added to the reaction solution, and the mixture was stirred and mixed at room temperature under a nitrogen stream. Then, EMA (11.3 g), tBA (13.5 g) as a monomer and EGDM (18.0 g) as a crosslinkable monomer, 2- (4 ′) as a monomer containing a living radical polymerization initiating group -Hydroxy-2 ', 2', 6 ', 6'-tetramethyl-1'-piperidinyloxy) -2- (3'-vinylphenyl) ethanol and 2- (4'-hydroxy-2', 2 ', 6', 6'-tetramethyl-1'-piperidinyloxy) -2- (4'-vinylphenyl) ethanol m / p mixture (compound 1 below, m / p ratio = 57/43, 2.25 g) and 2,2′-azobis (2,4-dimethylvaleronitrile) (ADVN, 0.450 g) as a polymerization initiator were added and dissolved. This mixed solution was gradually added to the reaction solution and stirred and mixed at room temperature for 3 hours. Thereafter, the reaction solution was heated to 65 ° C., subjected to a polymerization reaction at 65 ° C. for 5 hours and further at 85 ° C. for 2 hours, and then cooled to room temperature. Subsequently, the agglomerate was filtered off with a nylon mesh to obtain a particle dispersion. The core part was obtained by isolate | separating particle | grains with a centrifuge, wash | cleaning with water and methanol, and drying under reduced pressure. About the obtained core part, the average particle diameter and CV value, and the refractive index were measured by the method shown below. As a result, the average particle size was 176 nm, the CV value was 12%, and the refractive index (n (core)) of the core portion was 1.48.

<< Average particle diameter (nm) and CV value (%) >>
Using a light scattering photometer ELS-8000 (manufactured by Otsuka Electronics Co., Ltd.), the particles in the core part were measured by a dynamic light scattering method using ion-exchanged water as a dispersion medium, and the average particle diameter and CV value were calculated.
<< refractive index >>
The refractive index (n (core)) of the core is such that the coating liquid composed of the monomer for the core and 2,2′-azobis (2,4-dimethylvaleronitrile) which is the polymerization initiator has a thickness of The film was coated on a glass substrate so as to be 100 μm, and the film obtained by heating at 65 ° C. for 5 hours and further at 85 ° C. for 2 hours was peeled off from the glass and measured. The measurement was performed at 25 ° C. using an Abbe refractometer (manufactured by Atago Co., Ltd.).

[Production Example 2]
<Manufacture of core-shell particles (A)>
To a 500 mL four-necked flask equipped with a condenser, thermometer, stirrer and nitrogen inlet tube, N, N-dimethylformamide (DMF, 192 g) and 2-phenylphenoxyethyl acrylate (S) as a monomer (S) ( BPEA, see the following chemical formula, 42.0 g), styrene (St, 38.0 g), 2- (4′-hydroxy-2 ′, 2 ′, 6 ′) as a living radical polymerization initiator not bonded to the core particle , 6′-Tetramethyl-1′-piperidinyloxy) -2-phenylethanol (0.400 g) was added and dissolved. The core part (80.0g) obtained by manufacture example 1 was added to this, and it mixed for 30 minutes with the homogenizer, and dispersed the core part. The obtained dispersion was polymerized at 125 ° C. for 6 hours. THF was added to the contents, and the particles were separated by a centrifuge. The obtained particles were washed twice with THF and dried under reduced pressure to obtain core-shell particles. The obtained core-shell particles had a graft ratio of 30%, an average particle diameter of 211 nm, a CV value of 18%, and a refractive index (n (shell)) of the shell part of 1.60. In addition, the measurement of the average particle diameter and CV value of the core-shell particles was performed by using the core-shell particles instead of the core-portion particles and changing the dispersion medium to tetrahydrofuran (THF) by the method for the core portion. Moreover, the refractive index (n (shell)) of the shell part was measured using the monomer for the shell part instead of the monomer for the core part by the method for the core part.

[Production Example 3]
<Manufacture of colloidal crystal composition>
Core-shell particles (5.00 g) obtained in Production Example 2, BPEA (5.25 g) as the monomer (B1), and 9,9-bis [4- (2- (2- ( (Meth) acryloyloxyethoxy) phenyl] fluorene (FL1A, see chemical formula below, 2.25 g), diethylene glycol monobutyl ether acetate (DGBA, 3.75 g) and propylene glycol glycol monomethyl ether acetate (PGMA, 3.75 g) as organic solvents. In addition, the core-shell particles were dispersed by mixing for 60 minutes with a homogenizer. Subsequently, bis (2,4,6-trimethylbenzoyl) phenyl-phosphine oxide (Irgacure 819 (manufactured by BASF), 0.225 g) and 2-hydroxy-1- {4- [4- (2 -Hydroxy-2-methylpropionyl) benzyl] phenyl} -2-methylpropan-1-one (Irgacure 127 [manufactured by BASF Corp.], 0.150 g), BYK-355 ([manufactured by Big Chemie Japan Co., Ltd.) as a leveling agent, 0.0625 g) was added and mixed and dissolved to prepare a composition for colloidal crystals.

[Production Example 4-1-1]
<Adjustment of hard coat composition (1-1)>
As polyfunctional monomers and oligomers, EBECRYL-600 which is an epoxy acrylate (manufactured by Daicel Cytec Co., Ltd.), molecular weight: 500, number of functional groups: 2, 6.00 g), and butyl acetate (14. 0g), then 1-hydroxycyclohexyl phenyl ketone (Irgacure 184 [manufactured by BASF Corp.], 0.280 g) as a photopolymerization initiator, and BYK-UV3510 ([manufactured by Big Chemie Japan Co., Ltd.), 0.0700 g as a leveling agent ) Was added and dissolved to prepare a hard coat composition.

[Production Example 4-2-1]
<Adjustment of hard coat composition (2-1)>
As a multifunctional monomer and oligomer, purple light UV-1700B ([manufactured by Nippon Synthetic Chemical Industry Co., Ltd.], molecular weight: 2000, number of functional groups: 10, 6.00 g) 6.00 g) was used as a polyfunctional monomer and oligomer. Except for the above, a hard coat composition was prepared in the same manner as in Production Example 4.

[Production Example 4-2-2]
<Adjustment of hard coat composition (2-2)>
Except that EBECRYL-220 ([Daicel Cytec Co., Ltd.], molecular weight: 1000, number of functional groups: 6, 6.00 g) 6.00 g), which is urethane acrylate, was used as the polyfunctional monomer and oligomer. A hard coat composition was prepared in the same manner as in Production Example 4.

[Production Example 4-2-3]
<Adjustment of hard coat composition (2-3)>
EBECRYL-8701 which is a urethane acrylate ([Daicel Cytec Co., Ltd.], molecular weight: 2000, functional group number: 3, 6.00 g) 6.00 g) was used as the polyfunctional monomer and oligomer. A hard coat composition was prepared in the same manner as in Production Example 4.

[Production Example 4-3-1]
<Adjustment of hard coat composition (3-1)>
Except for using EBECRYL-3703 ([manufactured by Daicel Cytec Co., Ltd.], molecular weight: 850, number of functional groups: 2, 6.00 g) 6.00 g) as the polyfunctional monomer and oligomer. A hard coat composition was prepared in the same manner as in Production Example 4.

[Production Example 4-3-2]
<Adjustment of hard coat composition (3-2)>
EBECRYL-3701 which is an epoxy acrylate ([Daicel Cytec Co., Ltd.], molecular weight: 850, functional group number: 2, 6.00 g) 6.00 g) was used as the polyfunctional monomer and oligomer. A hard coat composition was prepared in the same manner as in Production Example 4.

[Production Example 4-3-3]
<Adjustment of hard coat composition (3-3)>
Except for using EBECRYL-210 ([Daicel Cytec Co., Ltd.], molecular weight: 1500, functional group number: 2, 6.00 g) 6.00 g) which is a urethane acrylate, as a polyfunctional monomer and oligomer. A hard coat composition was prepared in the same manner as in Production Example 4.

[Production Example 4-4-1]
<Adjustment of hard coat composition (4-1)>
The difunctional acrylate dipentaerythritol hexa (meth) acrylate (DPHA, molecular weight: 579, functional group number: 6, 6.00 g) 6.00 g) was used as the polyfunctional monomer and oligomer. A hard coat composition was prepared in the same manner as in Production Example 4.

[Production Example 4-4-2]
<Adjustment of hard coat composition (4-2)>
Production Example 4 except that polyfunctional acrylate pentaerythritol tri (meth) acrylate (PETA, molecular weight: 298, functional group number: 3, 6.00 g) 6.00 g) was used as the polyfunctional monomer and oligomer. In the same manner as above, a hard coat composition was prepared.

[Example 1-1]
<Production of optical laminate>
After applying the composition for colloidal crystals prepared in Production Example 3 to a PET film (Cosmo Shine A4300 [manufactured by Toyobo Co., Ltd.]) with a bar coater (# 26), a constant temperature oven (DNF600 [Yamato Scientific Co., Ltd.) ) Made]) and allowed to stand for 25 minutes at 90 ° C. to volatilize the organic solvent to crystallize the core-shell particles. Next, this colloidal crystal is irradiated with ultraviolet rays so that the integrated light quantity becomes 1000 mJ / cm ² using a high-pressure mercury lamp (ultraviolet irradiation device Toscure 401 [manufactured by Harrison Toshiba Lighting Co., Ltd.]). B1) and monomer (B2) were cured to obtain a cured colloidal crystal film. With respect to the obtained colloidal crystal cured film, the thickness of the colloidal crystal cured film was measured using a micrometer and found to be 26 μm. Moreover, the reflection wavelength and the reflectance were measured by the method shown below. As a result, this cured colloidal crystal film had a reflection peak at 548 nm, and the reflectance of the reflection peak was 69%. The refractive index (n (B)) after curing of the monomer (B1) and the monomer (B2) was 1.61.

<< Reflection wavelength (nm) and reflectance (%) >>
Measurement was performed using an ultraviolet-visible spectrophotometer V-560 (manufactured by JASCO Corporation) equipped with an integrating sphere device. Barium sulfate was used as a standard reflector. The spectral reflection spectrum of the cured colloidal crystal film was measured in the range of 350 to 850 nm, and the wavelength (nm) and reflectance (%) of the reflection peak were read.
<< refractive index >>
The refractive index (n (B)) after curing of the monomer (B1) and the monomer (B2) is bis (2,4,6-trimethylbenzoyl) phenyl which is each monomer and a photopolymerization initiator. -A coating solution made of phosphine oxide (Irgacure 819 [manufactured by Ciba Specialty Chemicals Co., Ltd.)] was applied on a glass substrate so as to have a thickness of 100 µm, and a film cured by ultraviolet irradiation of 1000 mJ / cm ² was formed. Measurement was performed by peeling from the glass. The measurement was performed at 25 ° C. using an Abbe refractometer (manufactured by Atago Co., Ltd.).

After the hard coat composition (1) prepared in Production Example 4 was applied to the obtained colloidal crystal cured film with a bar coater (# 10), the inside of the blast constant temperature thermostat (DNF600 [manufactured by Yamato Scientific Co., Ltd.]) And the organic solvent was volatilized at 90 ° C. for 1 minute. Next, the hard coat composition is cured by irradiating ultraviolet rays so that the integrated light amount becomes 500 mJ / cm ² using a high-pressure mercury lamp (ultraviolet irradiation device Toscure 401 [manufactured by Harrison Toshiba Lighting Co., Ltd.]). A laminate was obtained. As a result of measuring the film thickness of the hard coat layer using a micrometer, the obtained optical multilayer body was 5 μm. Further, this optical layered body had a reflection peak at 549 nm, and the reflectance of the reflection peak was 66%.
The resulting optical laminate had an abrasion resistance of 8% and an adhesion of 100/100.

《Abrasion resistance》
Using a Taber abrasion tester (abrasion wheel CS-10F), the haze value before and after the surface of a 100-rotation sample was abraded with a load of 500 g was measured with a haze meter (NDH5000 [manufactured by Nippon Denshoku Industries Co., Ltd.]). . The haze value was measured at four locations on the wear cycle orbit, and the average value was calculated. Abrasion resistance indicates a value (%) of (haze value after abrasion resistance test) − (haze value before abrasion resistance test). A haze change of less than 10% is practically excellent, and a haze change of 10-20% is practically sufficient, but the application is limited, and if the haze change exceeds 20%, the wear resistance is practical. Inferior.
<< Adhesion >> According to the cross-cut method of JIS-K5600, the surface of the test piece is cut with a cutter knife in the vertical and horizontal directions to a depth that reaches the light-transmitting substrate (S), and 100 cross-cuts are obtained. It was made and peeled after sticking an adhesive tape (cello tape [manufactured by Nichiban Co., Ltd .: registered trademark]). The number (n) of the grids remaining without peeling off the hard coat layer (H) and the cured colloidal crystal layer (C) is represented by n / 100.

[Examples 2-1 to 4-2]
In the same manner as in Example 1, an optical multilayer body was produced using the hard coat compositions (2-1) to (4-2). The results are shown in Table 1.

[Comparative Example 1]
Table 1 shows the results of a wear resistance test performed without preparing the hard coat composition.

In the result of Comparative Example 1, when there is no hard coat layer, the wear resistance is inferior. In the results of Examples 1-1 to 4-2, the wear resistance can be improved by forming a hard coat layer on the cured colloidal crystal film. Moreover, in the results of Examples 1-1 to 3-3, the wear resistance is improved, the reflectance is not affected before and after the formation of the hard coat, and the adhesion of each layer can be ensured. Furthermore, in the result of Examples 1-4, it has the abrasion resistance which can be used by each use, there is no influence on a reflectance before and after formation of a hard coat, and the adhesiveness of each layer can be ensured.

Since the optical multilayer body of the present disclosure has a colloidal crystal cured film as a functional layer, it reflects light in a specific wavelength region with high reflectance, and thus has excellent optical characteristics. Therefore, it is useful for optical functional materials such as optical filters. Furthermore, a cured film having a reflection peak from ultraviolet light to visible light and infrared light can be prepared according to the particle size of the core-shell particles used in the colloidal crystal cured film, which is useful for various optical elements. is there. Furthermore, the wear resistance according to each use can be ensured.

Claims (5)

In an optical laminate in which a colloidal crystal cured film layer and then a hard coat layer are sequentially laminated on a substrate,
The colloidal crystal cured film (C) is a cured film layer obtained by curing a core-shell particle (A) having a core part and a shell part and a monomer (B),
The core-shell particles are regularly and periodically arranged in the cured film layer,
The average particle diameter of the core part is 50 to 900 nm,
The refractive index (n (core)) of the core portion satisfies the following formulas (1) and (2),
n (shell) -n (core) ≧ 0.07 (1)
[Where n (shell) represents the refractive index of the shell portion]
n (B) -n (core) ≧ 0.07 (2)
[Wherein n (B) represents the refractive index after curing of the monomer (B)]
The shell is a linear polymer in which one end is covalently bonded to the core. The monomer (B) is a mixture of the monomer (B1) represented by the following formula (3) and the monomer (B2) represented by the following formula (4). The content of the monomer (B2) in B) is 5 to 70% by weight (however, the total of the monomer (B1) and the monomer (B2) is 100% by weight),
The optical layered product according to claim 1, wherein the linear polymer is formed of at least one of styrene and a monomer (S) represented by the following formula (3).

[In Formula (3), R ₁ is a hydrogen atom or a methyl group, and x is 0 or 1]

[In Formula (4), R ₂ is a hydrogen atom or a methyl group, and y is 1 or 2.]   The optical laminate according to claim 1, wherein the hard coat layer is a cured film of epoxy (meth) acrylate or urethane (meth) acrylate.   The optical laminate according to claim 3, wherein the epoxy (meth) acrylate has two or more (meth) acryloyl groups in one molecule and has a weight average molecular weight of 400 to 600. The optical laminate according to claim 3, wherein the urethane (meth) acrylate has 3 or more (meth) acryloyl groups in one molecule and has a weight average molecular weight of 500 to 4000.