JP2008276003A - Display material and automobile member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display material and an automobile member having high stability against vibration or impact by changing optical characteristics by an electric field. <P>SOLUTION: The display material 1 includes a partition wall 4 formed continuously by having a hydrophobic surface, and a structural color layer 6 for changing the optical characteristics by the electric field by being partitioned into a plurality of regions in a face by the partition. The display material is suitable as the automobile member such as a front glass. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a display material and an automotive member, and more particularly to a display material and an automotive member that have high resistance to vibration and impact and have high display performance.

  For example, an automotive member (automobile member) such as a windshield, which can arbitrarily control its optical characteristics, is important from the viewpoint of design, environment and energy saving. However, when a method for arbitrarily controlling optical characteristics is applied to a vehicle member such as an automobile, vibration and impact are applied, and color unevenness occurs, resulting in poor visibility. Various display materials have been studied so far, but there is almost no display material with excellent display performance against vibration and impact.

  On the other hand, the structural color is a coloring principle based on Bragg reflection of light having a specific wavelength with respect to a medium whose refractive index difference periodically changes, and corresponds to the color of a morpho butterfly in nature. Due to the peculiarity of the structural color, research on methods for displaying the structural color has been conducted (for example, see Patent Documents 1 to 3). Since structural color is a coloring principle that does not absorb light, it is basically expected to have high durability against light.

As described above, for example, in automobile applications, high stability against vibration and impact is one of the important properties. However, even when display materials using structural colors are used for applications with large vibrations and shocks such as automobiles, the cell gap becomes non-uniform, or the periodic structure of structural colors is disturbed, causing color unevenness, etc. Visibility is likely to deteriorate.
JP 2007-11112 A JP 2000-267123 A Japanese National Patent Publication No. 8-502837

  An object of the present invention is to provide a display material and an automobile member that can change optical characteristics by an electric field and have high stability against vibration and impact.

As a result of diligent research, the inventor of the present invention has extremely high stability against vibration and impact by applying a structural color layer having a continuous partition structure formed from a specific material having a hydrophobic surface. I found out that And this inventor obtained the knowledge that such a display material can be used suitably especially for the member for motor vehicles, and came to complete this invention, examining further based on this knowledge.
That is, in the present invention, the following display materials and automobile members are provided.

<1> A partition wall formed continuously and having a hydrophobic surface;
A structural color layer that is partitioned into a plurality of regions in the plane by the partition walls, and whose optical characteristics can be changed by an electric field;
A display material comprising:

<2> The display material according to <1>, wherein the structural color layer includes cholesteric liquid crystal and reflects light in a visible region, an infrared region, or an ultraviolet region.

<3> The display material according to <1> or <2>, wherein the structural color layer exists between a pair of electrodes, at least one of which is a transparent electrode, and is provided in a curved shape.

<4> The display material according to any one of <1> to <3>, wherein the structural color layer has a memory property.

<5> The display material according to any one of <1> to <4>, wherein the partition wall is formed by embossing.

<6> The display material according to any one of <1> to <5>, wherein the partition is formed of a photocurable resin or a thermosetting resin.

<7> The display material according to any one of <1> to <6>, wherein the partition wall is formed from a resin composition containing at least one fluorine-based monomer.

<8> a support;
A partition wall that is continuously formed in the in-plane direction of the support and has a hydrophobic surface;
A structural color layer that is partitioned into a plurality of regions in the plane by the partition walls, and whose optical characteristics can be changed by an electric field;
An automotive member characterized by comprising:

<9> The automotive member according to <8>, wherein an ultraviolet absorbing layer is disposed on at least one side of the structural color layer.

<10> The automotive member according to <8> or <9>, wherein a barrier layer is disposed on at least one side of the structural color layer.

<11> The electrode according to any one of <8> to <10>, further comprising an electrode for applying an electric field to the structural color layer, wherein the electrode is formed of a conductive polymer or a carbon nanotube. Automotive parts.

<12> The automotive member according to any one of <8> to <11>, further comprising a temperature sensor and a sheet-like heater.

  According to the present invention, it is possible to provide a display material and an automobile member that can change optical characteristics by an electric field and have high stability against vibration and impact.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification, “to” indicates a range including the numerical values described before and after the minimum and maximum values, respectively.

FIG. 1 schematically shows an example of the structure of a display material according to the present invention. FIG. 1A is a schematic perspective view, and FIG. 1B shows an enlarged part of a cross section along the line AA ′. The display material 1 is continuously formed in the in-plane direction of the support 2 and the support 2, and the partition 4 having a hydrophobic surface is partitioned into a plurality of regions in the plane by the partition 4. And a structural color layer 6 whose optical characteristics can be changed by an electric field. Such a display material 1 can be suitably applied to automobile members such as a windshield.
Hereinafter, each component will be specifically described.

<Support>
The support 2 is not particularly limited as long as it can form partition walls that are continuous in the in-plane direction and can support the structural color layer. For example, metal, glass, plastic, paper, ceramics, and the like are preferably used. be able to.

  As the metal for the support, for example, iron, stainless steel, and aluminum can be suitably used.

  Examples of the plastic (resin) for the support include, for example, triacetyl cellulose (TAC), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), syndiotactic polystyrene (SPS), polyphenylene sulfide (PPS), polycarbonate (PC ), Polyarylate (PAr), polysulfone (PSF), polyester sulfone (PES), polyetherimide (PEI), cyclic polyolefin, polyimide (PI), etc., preferably polyethylene terephthalate (PET).

  Further, the support resin preferably has a thermal expansion coefficient of 30 ppm / ° C. or less. The thermal expansion coefficient here is a value measured by TMA8310 (manufactured by Rigaku Corporation, Thermo Plus series). Specifically, PET (manufactured by Toray Industries, Lumirror, thermal expansion coefficient: 15 ppm / ° C.), PEN (manufactured by DuPont-Teijin, Q65A, thermal expansion coefficient: 20 ppm / ° C.), PI (manufactured by Ube Industries, Upilex, heat) Expansion coefficient: 20 ppm / ° C.), aramid resin (manufactured by Teijin Limited, thermal expansion coefficient: 2 ppm / ° C.), and the like.

  Further, a thermal expansion coefficient of 30 ppm or less may be achieved by adding an inorganic substance such as a sol-gel method, glass cloth, or glass fiber to a resin having a glass transition point (Tg) of 120 ° C. or higher as described below. Examples of preferable resins (the temperature in parentheses indicates Tg), polycarbonate resin (PC: 140 ° C.), alicyclic polyolefin resin (for example, ZEON Corporation, ZEONOR 1600: 160 ° C., JSR Corporation, Arton: 170 ° C.), polyarylate resin (PAr: 210 ° C.), polyethersulfone resin (PES: 220 ° C.), polysulfone resin (PSF: 190 ° C.), polyester resin (eg, Kanebo Co., Ltd., O-PET: 125 ° C., polyethylene) Terephthalate, polyethylene naphthalate), cycloolefin copolymer (COC, compound of Example 1 of JP 2001-150584 A, 162 ° C.), fluorene ring-modified polycarbonate resin (BCF-PC, implementation of JP 2000-227603 A) Compound of Example-4: 225 ° C.), alicyclic modification Recarbonate resin (IP-PC, compound of Example-5 of JP-A-2000-227603: 205 ° C.), acryloyl compound (compound of Example-1 of JP-A-2002-80616: 300 ° C. or more), etc. Is mentioned.

Moreover, as a resin substrate used as a support, a crosslinked resin can be preferably used from the viewpoint of solvent resistance, heat resistance, and the like. As a kind of crosslinked resin, various well-known things, such as a thermosetting resin, a photocurable resin, and a radiation curable resin, can be especially used without a restriction | limiting. For example, examples of the thermosetting resin include phenol resin, urea resin, melamine resin, unsaturated polyester resin, epoxy resin, silicone resin, diallyl phthalate resin, furan resin, bismaleimide resin, cyanate resin, and the like.
The crosslinking method can be applied without particular limitation as long as it is a reaction that forms a covalent bond. For example, a system in which a reaction proceeds at room temperature using a polyalcohol compound and a polyisocyanate compound to form a urethane bond. It can be used without particular limitation. However, such a system often has a problem of pot life before film formation, and is usually used as a two-component mixed type in which a polyisocyanate compound is added immediately before film formation. On the other hand, when used as a one-component type, it is effective to protect the functional group involved in the crosslinking reaction, and it is also commercially available as a block type curing agent. As commercially available block type curing agents, Mitsui Takeda Chemical Co., Ltd., B-882N, Nippon Polyurethane Industry Co., Ltd., Coronate 2513 (above block polyisocyanate), Mitsui Cytec Co., Ltd., Cymel 303 (Methyl) Melamine resin).

(Protective layer)
The support 2 may have a protective layer. Examples of the polymer used as the protective layer include water-soluble polymers, cellulose acylates, latex polymers, and water-soluble polyesters. Examples of water-soluble polymers include gelatin, gelatin derivatives, casein, agar, sodium alginate, starch, polyvinyl alcohol, polyacrylic acid copolymers, maleic anhydride copolymers, and cellulose acylates such as carboxymethyl cellulose and hydroxyethyl cellulose. Etc. Examples of the latex polymer include a vinyl chloride-containing copolymer, a vinylidene chloride-containing copolymer, an acrylate ester-containing copolymer, a vinyl acetate-containing copolymer, and a butadiene-containing copolymer.

The protective layer can contain inorganic or organic fine particles as a matting agent to such an extent that the transparency of the substrate (support) is not substantially impaired. As the inorganic fine particle matting agent, for example, silica (SiO ₂ ), titanium dioxide (TiO ₂ ), calcium carbonate, magnesium carbonate, or the like can be used. Examples of the organic fine-particle matting agent include polymethyl methacrylate, cellulose acetate propionate, polystyrene, a treatment liquid-soluble one described in US Pat. No. 4,142,894, US Pat. The polymers described in 396,706 can be used.
These fine particle matting agents preferably have an average particle size of 0.01 to 10 μm, more preferably 0.05 to 5 μm. The content of the fine particle matting agent is preferably 0.5 to 600 mg / m ² , more preferably 1 to 400 mg / m ² .

  As a method for forming the protective layer on the support substrate 2, a known method can be applied. For example, a solution for forming the protective layer is formed by a dip coating method, an air knife coating method, a curtain coating method, or a roller coating method. After coating on a support substrate by wire bar coating, gravure coating, slide coating, or extrusion coating using a hopper as described in US Pat. No. 2,681,294, drying. Thus, a protective layer can be formed.

(Antistatic layer)
An antistatic layer (conductive layer) may be formed on the support substrate 2. Specifically, the antistatic layer can be provided as a layer containing an ion conductive substance or conductive fine particles.

  Here, the ion conductive substance refers to a substance that shows electric conductivity and contains ions that are carriers for carrying electricity, and examples thereof include ionic polymer compounds. Specific examples of the ionic polymer compound include anionic polymer compounds such as those described in JP-B-49-23828, JP-B-49-23827, and JP-B-47-28937; 734, JP-A-50-54772, JP-B-59-14735, JP-B-57-18175, JP-B-57-18176, JP-B-57-56059, etc. Ionene type polymer having a dissociation group in: JP-B 53-13223, JP-B 57-15376, JP-B 53-45231, JP-B 55-145783, JP-B 55-65950, JP-B 55-67746 JP-B-57-11342, JP-B-57-19735, JP-B-58-56858, JP-A-61-27853, JP-B-62-9346 As seen in JP, mention may be made of cationic pendant polymers having a cationic dissociative group in the side chain.

On the other hand, examples of conductive fine particles include metal oxides such as ZnO, TiO ₂ , SnO ₂ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , MgO, BaO, MoO ₂ , and V ₂ O ₅ , or these A composite oxide of ZnO, TiO ₂ and SnO ₂ is particularly preferable. As examples including different atoms, for example, Al, In, etc. are added to ZnO, Nb, Ta, etc. are added to TiO ₂ , and Sb, Nb, halogen elements, etc. are added to SnO ₂ . Addition is effective. The amount of these different atoms added is preferably in the range of 0.01 to 25 mol%, particularly preferably in the range of 0.1 to 15 mol%.

(Other functional layers)
The support 2 may be provided with a smoothing layer, an adhesion improving layer, a light shielding layer, an antireflection layer, a hard coat layer, and the like as necessary.

<Structural color layer>
Next, the structural color layer 6 used in the present invention will be described. In the display material and the automobile member of the present invention, a structural color layer whose optical characteristics can be changed by an electric field is used.

The structural color is exhibited by Bragg reflection of light of a specific wavelength. Therefore, the “structural color layer” in the present invention means a periodic structure in which the difference in refractive index periodically changes so that light of a specific wavelength can be Bragg reflected, and the period is the wavelength of light. It is preferable that the size is about a submicro scale.
When the difference in refractive index changes periodically, Fresnel reflections that occur at interfaces having different refractive indexes are overlapped to cause interference, and as a result, the wavelength dependence of the reflectance and the change in reflectance are caused.

Such structural color layers include colloidal crystals using monodisperse particles of silica and polymers, microdomain structures of block copolymers, lamellar structures of surfactants, cholesteric liquid crystals with helical structures, and swordfish scales. Examples thereof include imitated inorganic layered compounds and polymer gels using monodisperse fine particles of silica or polymer as a template.
Here, the principle that the optical characteristics of the structural color layer as described above change depending on the electric field will be described.

-When using colloidal crystals-
FIG. 2 is a schematic diagram illustrating the colloidal crystal.
In colloidal crystals, there are an opal structure in which monodisperse particles are arranged in a closely packed structure, and an inverse opal structure obtained by filling the voids of the opal structure with another substance and removing the original particles. In the present invention, the voids of the opal structure may be filled with liquid crystal whose orientation changes according to the electric field, thereby changing the optical characteristics, or the liquid crystal is filled in the portion where the original particles of the inverse opal structure existed. May be.

Since the monodispersed particles or the portions where the particles originally existed are periodically arranged, only the light having a specific wavelength is reflected to exhibit a structural color. This relationship can be obtained by the Bragg equation represented by the following equation (1).
Formula (1): λ = 2ndsin θ
In equation (1), λ is the wavelength of the reflected light, d is the lattice spacing of the particles, and θ is the incident angle of the light.

  The voids between the particles are filled with liquid crystal whose optical characteristics change according to the electric field, or the liquid crystal is filled in the part where the particles originally existed. Thereby, the alignment of the liquid crystal changes according to the electric field, and the optical characteristics change.

-When using block copolymer-
The microdomain structure of the block copolymer forms a structure similar to the inverse opal structure in the colloidal crystal. The microdomain structure may be filled with a liquid crystal whose optical characteristics change according to the change in electric field.

-In case of lamellar structure with surfactant-
A surfactant is applied to the liquid crystal whose optical characteristics change in accordance with the change of the electric field, and a lamellar structure in which a number of liquid crystal layers are laminated by the surfactant is obtained. When the electric field is changed, the alignment of the liquid crystal changes and the optical characteristics change.

-Cholesteric liquid crystal-
In the present invention, a layer containing cholesteric liquid crystal can be suitably used as the structural color layer whose optical characteristics can be changed by an electric field. For example, a support substrate on which an electrode is formed is disposed oppositely, and at least one cholesteric liquid crystal layer is provided between the pair of electrodes. In this case, the cholesteric liquid crystal layer constituting the structural color layer preferably has a helical pitch adjusted so as to reflect light in the visible region, infrared region, or ultraviolet region.

FIG. 3A is a conceptual diagram showing a basic structure when a cholesteric liquid crystal exhibits a structural color due to a helical periodic structure. FIG. 3A shows a state when the cholesteric liquid crystal is horizontally aligned.
The structural color layer 10 is provided between the pair of electrodes 12. In this embodiment, since the liquid crystal used for the structural color layer is cholesteric liquid crystal, the helical periodic structure 16 is formed around the helical axis 14.

  FIG. 3B is a conceptual diagram of the helical periodic structure 16. The helical periodic structure 16 is shifted so that the molecular orientation vector of the liquid crystal rotates little by little around the helical axis 14, and the molecular orientation vector is different. The layers are stacked. The minimum unit of the spiral period is one pitch.

  In FIG. 3A, for convenience of explanation, the spiral pitch is shown as only one pitch, but actually, it has a structure in which this pitch is repeated as a minimum unit. That is, in the cholesteric liquid crystal, the helical periodic structure is regularly repeated.

Further, since FIG. 3B is illustrated in a simplified manner, four layers having different molecular orientation vectors are shown in the ½ pitch as four layers. Layers having different orientation vectors are formed.
Further, in FIGS. 3A and 3B, the helical axis is shown to be perpendicular to the electrode, but may be oriented with an angle to the right angle.

The reason why the reflected light is selectively emitted when light enters the structural color layer shown in FIG. 3 will be described.
The liquid crystal has a refractive index anisotropy (Δn). The refractive index anisotropy (Δn) here is defined as the difference between the refractive index (n‖) in the major axis direction of liquid crystal molecules and the refractive index (n⊥) in the minor axis direction of liquid crystal molecules as follows. Is done.

Δn = n‖−n⊥
Therefore, since there is a difference in the refractive index between the major axis direction and the minor axis direction of the liquid crystal molecules, the refractive index is periodically different for each layer having a different molecular orientation vector.

  When light is incident on this structure at an angle θ, light of a specific wavelength λ is selectively reflected and light of other wavelengths is transmitted based on the Bragg reflection formula. In the Bragg reflection formula, the lattice spacing d of particles is used in colloidal crystals, but the pitch length P is applied in cholesteric liquid crystals.

  When the electric field is changed in this state, the liquid crystal is aligned perpendicularly to the electrodes as shown in FIG. 4A, or in a disordered alignment state as shown in FIG. 4B.

In the case of FIG. 4A, since the liquid crystal is aligned perpendicular to the electrode, the refractive index of the liquid crystal is uniform. Therefore, since the refractive index does not change periodically, light is transmitted without exhibiting a structural color.
In the case of FIG. 4B, the alignment of the liquid crystal is disordered, and the refractive index does not change periodically. Moreover, light is scattered because the orientation direction is disordered. This is because, in the scattering state based on the random focal conic state, the scattering intensity increases as Δn of the host liquid crystal increases, and the display performance improves.
As described above, as shown in FIGS. 3 and 4, the alignment state of the liquid crystal can be switched by changing the electric field.

-Combination of inorganic layered compound and liquid crystal-
In the case of a structural color layer in which an inorganic layered compound and liquid crystal are combined, the inorganic layered compound is periodically stacked, and the gap is filled with liquid crystal. A structural color is exhibited by this periodically and regularly repeating layer structure.
When the electric field is changed in this state, the alignment of the liquid crystal changes and the optical characteristics change.

The structural color layer in the present invention is a periodic structure in which the difference in refractive index changes periodically. The structural color layer can adjust the wavelength of reflected light by changing its period. Considering the application, it is preferable to reflect light in the visible region, infrared region, or ultraviolet region.
For example, when the structural color layer is formed of a colloidal crystal, the wavelength of the reflected light can be adjusted by adjusting the particle size. In the microdomain structure of the block copolymer, the wavelength of reflected light can be adjusted by adjusting the polymerization conditions.
When the structural color layer is composed of cholesteric liquid crystals, the wavelength of the reflected light can be adjusted by adjusting the pitch length P. The adjustment of the pitch length P can be realized by changing the type of liquid crystal, changing the type of chiral agent, changing the addition amount of the chiral agent, or the like.

  The cholesteric liquid crystal that can be used as the structural color layer according to the present invention is not particularly limited as long as it can exhibit a structural color, but a liquid crystal compound exhibiting a nematic phase can be preferably used.

(Liquid crystal compound exhibiting nematic phase)
Specific examples of the nematic liquid crystal compound include azomethine compounds, cyanobiphenyl compounds, cyanophenyl esters, fluorine-substituted phenyl esters, cyclohexanecarboxylic acid phenyl esters, fluorine-substituted cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexane, fluorine-substituted phenylcyclohexane, and cyano. Examples thereof include substituted phenylpyrimidine, fluorine-substituted phenylpyrimidine, alkoxy-substituted phenylpyrimidine, fluorine-substituted alkoxy-substituted phenylpyrimidine, phenyldioxane, tolan compounds, fluorine-substituted tolan compounds, alkenylcyclohexylbenzonitrile, and the like. The liquid crystal compounds described on pages 154 to 192 and pages 715 to 722 of “Liquid Crystal Device Handbook” (Japan Society for the Promotion of Science 142nd edition, Nikkan Kogyo Shimbun, 1989) can be used. For example, Merck's liquid crystal (ZLI-4692, MLC-6267, 6284, 6287, 6288, 6406, 6422, 6423, 6425, 6435, 6437, 7700, 7800, 9000, 9100, 9200, 9300, 10,000, etc.) Liquid crystal (LIXON 5036xx, 5037xx, 5039xx, 5040xx, 5041xx, etc.) of Asahi Denka Co., Ltd. (HA-11757).

(Chiral agent)
The cholesteric liquid crystal used for the structural color layer is preferably a combination of a nematic liquid crystal and a chiral agent. When a chiral agent is added to a nematic liquid crystal, a cholesteric liquid crystal phase is formed.
The addition amount of the chiral agent is preferably 1 to 50% by mass in the liquid crystal composition, more preferably 1.5 to 20% by mass, and further preferably 2 to 30% by mass. When the amount of the chiral agent added is 50% by mass or less, it is possible to effectively prevent the viscosity of the liquid crystal composition from increasing and the responsiveness from decreasing, or precipitation of the chiral agent from the host liquid crystal.
A plurality of chiral agents may be used. In particular, it is preferable that the temperature dependence of the chiral pitch is reduced by using a combination of a positive and negative temperature dependence of the chiral pitch. Examples of the chiral agent include TN and STN chiral agents described on pages 199 to 202 of “Liquid Crystal Device Handbook” (edited by Japan Society for the Promotion of Science 142nd Committee, Nikkan Kogyo Shimbun, 1989).

Although the specific example of the chiral agent which can be used by this invention below is shown, it is not limited to these.

(Other additives)
For the purpose of changing the physical properties of the cholesteric liquid crystal to a desired range (for example, for the purpose of setting the temperature range of the liquid crystal phase to a desired range), a compound that does not exhibit liquid crystal properties may be added. Moreover, in order to prevent deterioration of the structural color layer, a compound such as an ultraviolet absorber or an antioxidant may be contained.

  For example, by providing a black layer on a substrate that is not on the side to be observed by a person, in this case, it is possible to electrically switch between a black state and a state in which light of a specific wavelength is reflected. For example, white color can be displayed by adjusting the wavelength of the reflected light to be the wavelength of the entire visible range and adjusting the cholesteric liquid crystal layer so that there are many reflection angles. That is, it is possible to reversibly switch between black and white electrically. Further, when cholesteric liquid crystal is used as the structural color layer, the structural color layer has a so-called memory property (display sustainability), and can maintain the state when the electric field is applied even after the application of the electric field is removed. Therefore, a display material with low power consumption can be constructed.

-When using gel-
For example, a structural color layer in which an isopropylacrylamide gel having a photonic crystal structure using a silica monomolecular particle having a diameter of about the wavelength of light as a template and an electrolyte liquid layer is provided between a pair of electrodes. Can do. In this case, the swelling and shrinkage of the gel can be controlled by applying an electric field, and the wavelength of the reflected light can be reversibly changed.

  In the display material of the present invention, a plurality of structural color layers that reflect light in different wavelength ranges may be arranged on the same surface, or may be laminated. The light reflected by the structural color layer is not limited and may be of any wavelength. Thus, the structure which provides a some structural color layer increases the number of the colors which can be displayed, and can improve design nature more.

<Partition wall>
In the display material and the automobile member of the present invention, the partition wall 4 having a hydrophobic surface is continuously formed, and the structural color layer 6 is partitioned into a plurality of regions within the surface by the partition wall 4. Exists.
The partition 4 has a hydrophobic surface. The hydrophobicity here means that the contact angle of water on the surface of the partition wall is in the range of 30 ° to 180 °, and preferably in the range of 50 ° to 180 °. Such a partition having a hydrophobic surface is preferably a polymer structure having a long-chain alkyl group or a fluorine-substituted alkyl group.
The long-chain alkyl group is preferably an alkyl group having 3 to 60 carbon atoms, more preferably an alkyl group having 4 to 30 carbon atoms, and still more preferably an alkyl group having 4 to 20 carbon atoms.
The fluorine-substituted alkyl group is preferably a fluoroalkyl group having 2 to 60 carbon atoms, more preferably a fluoroalkyl group having 2 to 30 carbon atoms, and still more preferably a fluoroalkyl group having 4 to 20 carbon atoms. The fluoroalkyl group may be one in which some hydrogen atoms are substituted with fluorine atoms, or may be a perfluoroalkyl group. However, from the viewpoint of enhancing hydrophobicity, the fluoroalkyl group may be a perfluoroalkyl group. preferable.

  Such a surface is hydrophobic, and the structural color layer 6 is partitioned into a plurality of parts by a continuous partition structure, so that even if a vibration or impact is applied to the display material 1 according to the present invention, the continuous partition structure Is absorbed efficiently. Therefore, even when the periodic structure of the structural color layer 6 is disturbed by vibration or impact, the original periodic structure can be quickly returned. In particular, since the surface of the partition wall 4 is hydrophobic, the interaction with the liquid crystal present in the structural color layer is reduced, and even if it becomes unstable and distorted due to vibration or impact, the original stability is promptly achieved. The periodic structure is restored, which is extremely advantageous in terms of enhancing stability against vibration and impact.

The structure of the partition wall 4 is not particularly limited as long as the structural color layer 6 can be divided into a plurality of regions, and the structural color layer 6 can exhibit a structural color. In order to absorb efficiently by a partition structure, it is preferable to form in a regular pattern. For example, as shown in FIG. 5, partition structures such as (A) a circular cup shape, (B) an elliptical shape, (C) a lattice shape, and (D) a honeycomb shape are mentioned, and preferably a cup shape or a lattice shape. It has a honeycomb shape. If it is a cup-shaped partition wall, it is preferable from the viewpoint that it can be easily formed by embossing. On the other hand, if it is a lattice-shaped or honeycomb-shaped partition wall, the aperture ratio (of the portion where the structural color layer is disposed) The ratio can be increased, which is preferable.
In the display material shown in FIG. 1B, the portion where the structural color layer 6 is disposed does not penetrate, but may penetrate.

The size of each region partitioned by the partition 4 is not particularly limited, and may be set as appropriate in consideration of the use of the display material, the required impact resistance, and the like.
Regarding the length of one side or the diameter of the region partitioned by each partition wall 4, it is possible to reliably improve the stability of the structural color layer 6 against vibration and impact, and to prevent the visibility of the structural color layer 6 from being lowered. In consideration, a range of 1 μm to 10 cm is preferable, a range of 10 μm to 1 cm is more preferable, and a range of 20 μm to 1 mm is more preferable.

  In addition, the height of the partition wall may be appropriately set in consideration of the use of the display material and the required impact resistance, etc., and the structural color layer is reliably partitioned to improve stability against vibration and impact, In order to prevent the partition wall from collapsing due to impact, the range of 1 μm to 1 cm is preferable, the range of 5 μm to 1 mm is more preferable, and the range of 10 μm to 50 μm is more preferable.

  The thickness of the partition wall 4 may be set as appropriate in consideration of the use of the display material and the required impact resistance. However, the structural color layer 6 should be reliably partitioned to improve the stability against vibration and impact. From the standpoints of preventing the partition wall from collapsing and preventing the structural color layer from being lowered in visibility, the range of 0.1 μm to 1000 μm is preferable, and the range of 0.5 μm to 500 μm is more preferable. More preferably, it is the range of 1 micrometer-100 micrometers.

The material constituting the partition is not particularly limited as long as the surface is hydrophobic and the structural color layer 6 can be separated into a plurality of parts, but is preferably a hydrophobic resin.
In addition, as a method for forming the partition walls, it is preferable to form the partition walls by a method in which an external energy such as heat, light, and gamma rays is applied to the resin for forming the partition walls and cured. Particularly preferred is a method in which a partition wall is formed by polymerizing a thermosetting or photocurable monomer in a mold. In the polymerization, it is preferable to use UV light as irradiation light.

The thermosetting or photocurable resin for forming the partition walls can be synthesized using monomers such as acrylate, methacrylate, acrylamido, methacrylamide, epoxy, vinyl, vinyl ether, styrenic monomer, It is a resin synthesized using acrylate or methacrylate monomers.
As the monomer used for forming the partition wall, an acrylate or methacrylate having a long-chain alkyl group, or an acrylate or methacrylate having a fluorine-substituted alkyl group is preferable.
Specifically, dipentaerythritol dodecaacrylate, dipentaerythritol hexaacrylate, dipentaerythritol octaacrylate, dipentaerythritol dodecamethacrylate, dipentaerythritol hexamethacrylate, ethylene glycol diacrylate, polyethylene glycol diacrylate perfluorohexyl ethyl Acrylate, perfluorohexylethyl methacrylate, perfluorooctylethyl acrylate, divinylbenzene, and the like, such as dipentaerystol dodecaacrylate, dipentaerythritol hexaacrylate, perfluorohexylethyl acrylate, dipentaerythritol octaacrylate, dipenta Elistole dodeca methacrylate is preferred It is. In order to form a partition wall having a hydrophobic surface, it is particularly preferable that the partition wall is formed from a resin composition containing at least one fluorine-based monomer.
Moreover, the monomer used may be monofunctional or polyfunctional. Polyfunctional monomers are preferred, and it is also preferred to use them in combination with monofunctional monomers. In addition, as a polyfunctional monomer, a bifunctional, a trifunctional, a tetrafunctional, a pentafunctional, and a hexafunctional monomer are suitable.

In addition to the above monomers, a viscosity adjusting agent for adjusting the viscosity, a surfactant for adjusting the wettability, and the like can be suitably added to the material for forming the partition walls.
Moreover, another polymer can be added for the purpose of controlling various physical properties. Examples of such a polymer include polyester, polyamide, polyvinyl alcohol, cellulose, polyether, polysulfone, and polyimide.

  Moreover, it is preferable to add a polymerization initiator for causing polymerization by external energy. What is necessary is just to select as a polymerization initiator according to the monomer etc. to be used, and a photoinitiator or a thermal-polymerization initiator can be used suitably.

  The means for forming the partition is not particularly limited, but it is preferable to form the partition by embossing. For example, after applying a polymer solution containing the monomer or the like on the support, it is heated to a predetermined temperature (preferably higher than the Tg of the polymer). Next, it is preferable to press a mold processed so as to form a partition having a desired shape, and thereafter or simultaneously polymerize and cure the monomer by light irradiation or heating. This process is preferably roll-shaped web processing from the viewpoint of reducing manufacturing costs.

<Electrode>
Since the display material of the present invention changes the optical characteristics of the structural color layer according to the electric field, it is preferable to provide an electrode on the support. The material, shape, position, etc. of the electrode are not particularly limited as long as a voltage can be applied so that the optical characteristics of the structural color layer can be changed, and can be appropriately selected. For example, the electrode can be suitably formed from a metal such as gold, silver, copper, or aluminum.
In addition, for example, when the display member according to the present invention is applied to an automobile member, a conductive polymer or a carbon nanotube can also be employed as an electrode for applying an electric field to the structural color layer. An electrode made of a conductive polymer or a carbon nanotube is preferable because the deterioration when applied to a curved surface is small.
Further, for example, indium oxide, ITO (indium tin oxide), tin oxide, or the like can be used as the transparent electrode. As for the transparent electrode, for example, those described in pages 232 to 239 of “Liquid Crystal Device Handbook” (edited by the Japan Society for the Promotion of Science 142nd Committee, Nikkan Kogyo Shimbun, 1989) are used.

  The driving method is not particularly limited as long as the optical characteristics of the structural color layer can be changed by an electric field, but two supports having transparent electrodes formed on at least one of them are arranged to face each other and formed on these supports. A structure in which a structural color layer is sandwiched between a pair of electrodes is preferable. In this case, the structural color layer can be provided in a curved shape.

  Further, an in-plane driving method in which electrodes are formed only on one side of the support can also be suitably used. In this case, a comb electrode structure can be obtained. In this way, when the electrode is provided only on one substrate (support), the latitude with respect to the thickness of the structural color layer is widened. Therefore, when applied to a double curved surface such as an automobile, display unevenness is reduced. There are benefits.

<Other members>
The display material and the automobile member according to the present invention include other members such as a barrier layer, an ultraviolet absorption layer, an antireflection layer, a hard coat layer, a stain prevention layer, an organic interlayer insulating film, a metal reflector, a retardation plate, An alignment film or the like can be provided. These may be used alone or in combination of two or more.

As the barrier layer, an inorganic layer formed from silica or the like, or a structure in which an inorganic layer and an organic layer are stacked can be suitably used. By providing such a barrier layer, intrusion of water and oxygen in the atmosphere is suppressed, and deterioration of the structural color layer can be effectively prevented.
Examples of a method for forming such a barrier layer include sputtering, vapor deposition, or sol-gel method for inorganic layers such as silica, and organic layer includes application of a monomer solution, polymerization process or vapor deposition, and polymerization process. In particular, the inorganic layer is preferably formed by sputtering, and the organic layer is preferably formed by a coating process.

  As the ultraviolet absorbing layer, an antioxidant such as 2,2-thiobis (4-methyl-6-t-butylphenol) and 2,6-di-t-butylphenol, 2- (3-t-butyl-5-methyl) It is preferable to contain ultraviolet absorbers such as 2-hydroxyphenyl) -5-chlorobenzotriazole and alkoxybenzophenone.

  The antireflection layer can be formed using an inorganic material or an organic material, and the layer structure may be a single layer or a multilayer. An antireflection layer having a multilayer structure of an inorganic material film and an organic material film may be used. The antireflection layer can be provided on one side or both sides. When providing an antireflection layer on both surfaces, the antireflection layers on both surfaces may have the same configuration or different configurations.

The inorganic material used for the antireflection _{layer, SiO 2, SiO, ZrO 2} , TiO 2, TiO, Ti 2 O 3, Ti 2 O 5, Al 2 O 3, Ta 2 O 5, CeO 2, MgO, Y 2 O ₃ , SnO ₂ , MgF ₂ , WO _{3 and the} like can be mentioned, and these can be used alone or in combination of two or more. Among these, for example, when a plastic resin substrate is used as the support, SiO ₂ , ZrO ₂ , TiO ₂ , and Ta ₂ O ₅ that can be vacuum-deposited at a low temperature are preferable.

As the multilayer film formed of an inorganic material, for example, the total optical film thickness of the ZrO ₂ layer and the SiO ₂ layer is λ / 4, the optical film thickness of the ZrO ₂ layer is λ / 4, and the outermost SiO ₂ layer A laminated structure in which a high refractive index material layer and a low refractive index material layer having an optical film thickness of λ / 4 are alternately formed is exemplified. Here, λ is a design wavelength, and usually 520 nm is used. The outermost layer is preferably made of SiO ₂ because it has a low refractive index and can impart mechanical strength to the antireflection layer.
When the antireflection layer is formed of an inorganic material, for example, a vacuum deposition method, an ion plating method, a sputtering method, a CVD method, a method of depositing by a chemical reaction in a saturated solution, or the like can be employed.

  Examples of the organic material used for the antireflection layer include FFP (tetrafluoroethylene-hexafluoropropylene copolymer), PTFE (polytetrafluoroethylene), ETFE (ethylene-tetrafluoroethylene copolymer), and the like. The refractive index of the lens material and the hard coat layer (if any) may be selected. As a film forming method, the film can be formed by a coating method having excellent mass productivity such as a spin coating method and a dip coating method in addition to a vacuum deposition method.

As the hard coat layer, a known ultraviolet curing or electron beam curing acrylic or epoxy resin can be used.
As the antifouling layer, a water / oil repellent material such as a fluorine-containing organic polymer can be used.

  As the alignment film, it is preferable to use polyimide, a silane coupling agent, polyvinyl alcohol, gelatin, or the like, and it is preferable to use polyimide or a silane coupling agent from the viewpoints of alignment ability, durability, insulation, and cost. The orientation method may or may not be rubbed. Regarding the alignment state, either the horizontal state or the vertical state may be used.

  As described above, the display material and the automotive member according to the present invention have a hydrophobic surface, and the structural color layer is partitioned by the continuously formed partition walls, so that it is continuous even when vibration or impact is applied. Even when the periodic structure of the structural color layer is disturbed by vibration or impact, the original periodic structure can be promptly restored. Accordingly, the display material and the automobile member according to the present invention can exhibit high stability against vibration and impact.

<Application>
If the display material of the present invention is applied to the windshield, side glass, rear glass, sunroof, rearview mirror, etc. of an automobile, it can reflect light of any wavelength. Improvement in security, security measures by light shielding, improvement in design, etc. can be achieved. For example, if an automotive member further includes a temperature sensor and a sheet heater, it is possible to suppress deterioration in display performance under a low temperature environment such as below freezing point.
In addition, the display material of the present invention is not limited to the above-described automotive member, and can be suitably used as, for example, an interior, advertisement, information display medium, etc. that is resistant to vibration and impact.

  Hereinafter, the present invention will be described more specifically based on examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the following examples.

[Example 1]
1. Production of Plastic Substrate An undercoat layer and a back layer were formed on PEN (Dupont-Teijin Q65A) in the same manner as in the production of Sample 110 of Example 1 of JP-A-2000-105445. That is, 100 parts by weight of polyethylene-2,6-naphthalate polymer and Tinuvin P.I. 326 (manufactured by Ciba-Geigy Ciba-Geigy) was dried, melted at 300 ° C., extruded from a T-die, and stretched 3.3 times at 140 ° C., followed by 130 ° C. Then, the film was stretched by 3.3 times and further heat fixed at 250 ° C. for 6 seconds to obtain a plastic film substrate (PEN) having a thickness of 90 μm. An undercoat layer and a back layer were formed on this PEN substrate.

2. Formation of Transparent Electrode Layer Conductive indium tin oxide (ITO) was coated on one side of the plastic substrate obtained as described above by vapor deposition, and a uniform thin film having a thickness of 200 nm was laminated. The surface resistance was about 20 Ω / cm ² and the light transmittance (wavelength: 500 nm) was 85%. Next, a SiO ₂ thin film (100 nm) was provided by sputtering as an antireflection film on the ITO surface. The light transmittance (wavelength: 500 nm) was 90%.

3. Preparation of UV curable monomer / Monomer: Dipentaerythritol dodecaacrylate 8.0g
Photopolymerization initiator: 0.6 g of 2-hydroxy-2-methylpropiophene
(Ciba Specialty Chemicals)
・ Diluent: Triloxyethyl acrylate 8.0g
(Manufactured by Soken Chemical Industry Co., Ltd.)
The above components were mixed with stirring to obtain a colorless and transparent liquid of about 20 mPa · s.

4). Formation of Partition Wall The UV curable monomer was applied on the electrode of the plastic substrate on which the transparent electrode was formed. Next, it is pressed against an embossing mold (lattice spacing: 100 μm, partition wall thickness: 10 μm, height: 10 μm) while being heated to 80 ° C., and in this state, UV light is applied at a light intensity of 50 mJ / cm ² on the coated surface. Irradiated for 10 minutes. Thereafter, the mold was separated from the substrate to form partition walls on the substrate. The obtained partition wall had a water contact angle of 65 °.

5. Preparation of cholesteric liquid crystal solution In 10.0 g of nematic liquid crystal (ZLI-1132, manufactured by Merck), a chiral agent (R-1011, manufactured by Merck) was added in an amount having a selective reflection peak at a wavelength of 550 nm, and methyl ethyl ketone was further added. Cholesteric liquid crystal solution was prepared by adding 10 ml of (MEK).

6). Filling of Cholesteric Liquid Crystal and Lamination of Upper Film The film substrate on which the partition walls were formed was heated to 70 ° C., and the cholesteric liquid crystal solution was poured on the side where the partition walls were formed to fill between the partition walls. The mixture was heated for 1 hour under reduced pressure to distill off MEK as the solvent.
Next, an adhesive containing a UV curing agent was applied to the upper surface of the grid-like partition walls by screen printing. After laminating another film on which the same transparent electrode as described above was formed as the upper film, UV irradiation was performed. Thus, the upper film was adhered to the upper surface of the partition wall to obtain a display material.

(Evaluation of display performance)
When an alternating voltage ± 100 V (100 Hz) is applied to the display material obtained as described above using a signal generator (manufactured by Tektronix Co., Ltd.) and then the applied voltage is instantaneously reduced to zero, the cholesteric liquid crystal is It became a planar state and showed a selective reflection peak at 550 nm. This state was confirmed to exist stably at room temperature for one month or more and to have good display maintainability. When an alternating voltage of ± 40 V (100 Hz) was applied and the applied voltage was gradually reduced to zero, the cholesteric liquid crystal became a focal conic state and became transparent. It was confirmed that this state existed stably for more than one month at room temperature and had good display maintenance (memory property).

(Evaluation of vibration resistance)
The obtained display material was subjected to a vibration test according to MIL-STD-883E under the following conditions. After applying vibration from 20 Hz to 1000 Hz, the process of returning to 20 Hz was set to 1 cycle (about 4 minutes), and this was performed for 4 cycles. After this test, the display performance was evaluated. In particular, the display performance was not deteriorated (display unevenness, display contrast ratio decrease, etc.). That is, it was confirmed that the display material of Example 1 is excellent in stability against vibration.

(Evaluation of impact resistance)
About the impact resistance of the obtained display material, it tested by the test method shown by 5.5 of JISD5500. As a result, no deterioration in display performance (display unevenness, reduction in display contrast ratio, etc.) was observed. Thereby, it was confirmed that the display material of Example 1 has high stability against impact.

(Evaluation of light durability)
The display material of Example 1 was irradiated with Xe lamp (150,000 lux) (480 hours), but the electrical characteristics were not changed. Thereby, it was confirmed that the display material of Example 1 is excellent in light durability.

(Evaluation of wet heat durability)
The display material of Example 1 was allowed to stand for 3 weeks in an environment with a humidity of 85% and a temperature of 80 ° C., but there was no change in electrical characteristics. Thereby, it was confirmed that the display material of Example 1 is excellent in wet heat durability.

(Evaluation as window glass for automobiles)
The display material of Example 1 was bonded to an automobile windshield, rear glass, and sunroof from the inside using an epoxy adhesive. Each of these glasses was not a flat surface but a double curved surface.
A pressure-sensitive adhesive was applied to the films on both sides of the display material, and then sandwiched between two tempered glasses to produce a laminated glass. In this state, when the electrical characteristics were evaluated, the display performance was not particularly deteriorated. That is, it was confirmed that the display material of Example 1 can be suitably used as a light control glass for automobiles.

(effect)
By separating the structural color layers with a continuous partition wall structure, vibration resistance and impact resistance are greatly improved, and a display material capable of stable display can be obtained, and can be used particularly preferably for automobiles. Moreover, since the display material of Example 1 displays a color without absorbing light by the structural color layer, it is excellent in durability particularly when used outdoors. Therefore, the display material of Example 1 can be particularly suitably used for automobile members. For example, if the display material of Example 1 is provided on a window glass of an automobile, etc., it is possible to easily adjust the illuminance in the automobile room even in a sunny place outdoors, thereby improving comfort. Can be made. For example, when the display material according to the first embodiment is applied to the windshield, it is possible to shield the glare at the exit of the tunnel or the direct sunlight from the sun, thereby enabling safer driving. Further, in summer, it becomes possible to prevent the temperature inside the vehicle from rising, reducing the load on the air conditioner in the vehicle, resulting in improved fuel efficiency.

[Example 2]
A film substrate was prepared in the same manner as in Example 1, and a comb-shaped electrode (interval 25 μm) was drawn on one film substrate by an inkjet method using a gold nanoparticle solution (average particle size: 3.0 nm). And firing. A display material provided with a cholesteric liquid crystal layer exhibiting selective reflection between continuous partition walls was produced by the same operation as in Example 1 using the film substrate with the comb electrode and the film substrate without the electrode. . As monomers, 6.0 g of dipentaerythritol hexaacrylate and 2.0 g of perfluorohexylethyl acrylate were used instead of dipentaerythritol dodecaacrylate. The water contact angle of the obtained partition wall was 85 °. Next, this display material was bonded onto an automobile body coated with a black paint using an adhesive layer.

(Evaluation of display performance)
When an alternating voltage ± 100 V (100 Hz) is applied to the display material obtained as described above using a signal generator (manufactured by Tektronix Co., Ltd.) and then the applied voltage is instantaneously reduced to zero, the cholesteric liquid crystal is It became a planar state and showed a selective reflection peak at 550 nm. This state was stably maintained at room temperature for one month or more, and it was confirmed that the display had good display maintainability.
When an alternating voltage of ± 40 V (100 Hz) was applied and the applied voltage was gradually reduced to zero, the cholesteric liquid crystal became a focal conic state and became black. This state was stably maintained at room temperature for one month or more, and it was confirmed that there was a good display maintaining property (memory property).
Furthermore, when the same evaluation as in Example 1 was performed with respect to vibration resistance and impact resistance, no significant reduction in display performance was observed, and the display material of Example 2 was excellent in vibration resistance and impact resistance. Was confirmed.

[Example 3]
Polycarbonate (manufactured by Teijin) was used as a curved plastic substrate, and a PEDOT / PSS aqueous dispersion (manufactured by Nagase Chemical Co.) was applied as a conductive polymer to the substrate, followed by drying (film thickness: 8 μm, sheet resistance: About 500Ω / cm ² , light transmittance (wavelength 500 nm): 88%). Thereby, a transparent electrode was formed on one side of the substrate.
A highly hydrophobic partition wall was formed on the transparent electrode side on the substrate in the same manner as in Example 1 to produce a sheet-shaped display material. In addition, as the cholesteric liquid crystal, fluorine-based liquid crystal (ZLI-4792, manufactured by Merck & Co., Inc.) was used. A PVB (polyvinyl butyral) film was provided on both surfaces of the obtained sheet-like display material to form a laminated glass, and a sunroof having a double curved surface was produced. At the time of production, a current-carrying wiring was taken from the electrode part.

(Durability evaluation)
The sunroof produced as described above was irradiated with Xe lamp (150,000 lux) (480 hours), but the electrical characteristics did not change. As a result, it was confirmed that the sunroof was excellent in light durability.
The sunroof was allowed to stand for 3 weeks in an environment of 85 ° C. and 95% humidity, and the electrical characteristics were evaluated by light irradiation similar to the above. However, the electrical characteristics did not change. Thereby, it was confirmed that the sunroof of Example 3 was excellent in stability under high temperature and high humidity.
Furthermore, after the sunroof was allowed to stand for 1 week in an environment of −20 ° C., the electrical characteristics were evaluated by light irradiation similar to the above, but there was no change in the electrical characteristics. Thereby, it was confirmed that the sunroof of Example 3 was excellent also in stability under low temperature.

(Evaluation of stability against shock and vibration)
When the stability against shock and vibration was evaluated in the same manner as in Example 1, it was confirmed that the sunroof in Example 3 showed high stability.

(effect)
From the above evaluation, it was confirmed that the display material produced in Example 3 is suitable as an automobile member having a double curved surface such as a sunroof, and the structural color can be electrically switched. In addition, it was confirmed that the automobile part (sun fool) manufactured in Example 3 has high stability against light, heat, humidity, impact, and vibration.

[Example 4]
A curved automobile part was produced by the same operation as in Example 1. An ultraviolet absorbing layer (UV guard, manufactured by Fuji Film Business Supply Co., Ltd.) was provided on the support on the light incident side.

(Evaluation of light durability)
It was confirmed that the automobile part of Example 4 showed little deterioration in display performance due to ultraviolet irradiation.

[Example 5]
A curved automobile part was produced by the same operation as in Example 1. However, it was not a laminated glass. Furthermore, a barrier layer was provided on the support on the side on which light was incident. For the barrier layer, an inorganic layer (aluminum oxide) was formed as a first inorganic layer using a sputtering apparatus.
Next, on the inorganic layer, as a first organic layer, 20 g of a monomer (M-1) having the structure shown below, 0.6 g of an ultraviolet polymerization initiator (Ciba IRGACURE (registered trademark) 184), 2- A mixed solution containing 200 g of butanone was applied using a wire bar so that the liquid film thickness was 5 μm.
Monomer (M-1)

After the application of the mixed solution, it was cured by irradiation with ultraviolet light from a high-pressure mercury lamp at room temperature (integrated irradiation amount: about ² J / cm ² ) to form a first organic layer.
In each case, the thickness of the inorganic layer and the organic layer was about 500 nm.

  By the same operation, the barrier layer was formed by forming the second inorganic layer, the second organic layer, the third inorganic layer, and the third organic layer, respectively.

(Durability evaluation)
It was confirmed that the automobile parts produced as described above have little deterioration in display performance due to high humidity.

[Example 6]
A sheet-like automobile part was produced in the same manner as in Example 1. In addition, a sheet-shaped transparent heater (Honeywell, Elmwood 7800 series) and a temperature sensor (National Semicon, LM35) are installed on one side. The temperature was set so as to be maintained at a temperature higher than ℃.

(Evaluation)
It was confirmed that the automobile part of Example 6 showed a good display performance even under a freezing environment.
[Example 7]
The automobile part of the present invention was produced by the same operation as in Example 1. As monomers, 6.0 g of dipentaerythritol octamethacrylate and 3.0 g of perfluorooctylethyl acrylate were used instead of dipentaerythritol dodecaacrylate. As a result, it was confirmed that the same effect as in Example 1 was obtained.

As mentioned above, although the display material and the member for motor vehicles based on this invention were demonstrated, this invention is not limited to the said embodiment and Example.
For example, in the above-described embodiments and examples, the case where the partition is separately formed on the support has been described, but the support and the partition may be integrally formed.

It is a figure which shows schematically an example of a structure of the display material which concerns on this invention, FIG. 1 (A) is a perspective view, FIG.1 (B) followed the AA 'line of FIG. 1 (A). It is the figure which expanded a part of cross section. It is a schematic diagram explaining a colloidal crystal. FIG. 3A is a conceptual diagram showing a basic structure when a cholesteric liquid crystal exhibits a structural color by a helical periodic structure, and FIG. 3B is a diagram for explaining the helical periodic structure. FIG. 4A is a diagram illustrating a state when a cholesteric liquid crystal does not exhibit a structural color. In FIG. 4A, the liquid crystal is aligned perpendicular to the electrode, and FIG. It is a figure which shows a mode that it has become. It is a top view which shows roughly the example of the partition structure concerning this invention, and is (A) circular shape (cup shape), (B) elliptical shape, (C) lattice shape, (D) honeycomb shape.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Display material 2 Support body 4 Partition 6 Structural color layer 10 Structural color layer 12 Electrode 14 Helical axis 16 Helical periodic structure

Claims (12)

A partition wall formed continuously and having a hydrophobic surface;
A structural color layer that is partitioned into a plurality of regions in the plane by the partition walls, and whose optical characteristics can be changed by an electric field;
A display material comprising:   The display material according to claim 1, wherein the structural color layer includes cholesteric liquid crystal and reflects light in a visible region, an infrared region, or an ultraviolet region.   The display material according to claim 1, wherein the structural color layer is provided between a pair of electrodes, at least one of which is a transparent electrode, and is provided in a curved shape.   The display material according to any one of claims 1 to 3, wherein the structural color layer has a memory property.   The display material according to claim 1, wherein the partition walls are formed by embossing.   The display material according to claim 1, wherein the partition wall is formed of a photocurable resin or a thermosetting resin.   The display material according to any one of claims 1 to 6, wherein the partition wall is formed from a resin composition containing at least one fluorine-based monomer. A support;
A partition wall that is continuously formed in the in-plane direction of the support and has a hydrophobic surface;
A structural color layer that is partitioned into a plurality of regions in the plane by the partition walls, and whose optical characteristics can be changed by an electric field;
An automotive member characterized by comprising:   The automobile member according to claim 8, wherein an ultraviolet absorbing layer is disposed on at least one side of the structural color layer.   The automotive member according to claim 8 or 9, wherein a barrier layer is disposed on at least one side of the structural color layer.   The automobile according to any one of claims 8 to 10, further comprising an electrode for applying an electric field to the structural color layer, wherein the electrode is formed of a conductive polymer or a carbon nanotube. Materials.   The automotive member according to any one of claims 8 to 11, further comprising a temperature sensor and a sheet-like heater.

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