JP2009237092A - Phase retarder and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a phase retarder superior in slidability, blocking preventability and foreign matter mixture avoidance. <P>SOLUTION: In the phase retarder, an optical anisotropic layer contains fine particles as a blocking-preventing agent. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a phase difference body excellent in slipperiness, antiblocking property, and foreign matter avoidance in a production process, and a method for producing the same.

  The liquid crystal display device includes a liquid crystal cell, a polarizing element, and a phase difference body (optical compensation sheet) as its basic configuration. The phase difference body is used to prevent coloring of the image displayed on the display and to widen the viewing angle of the image displayed on the display (Patent Document 1: Japanese Patent Application Laid-Open No. 2007-304375). . The phase difference body is generally produced by forming an arbitrary functional layer such as an optically anisotropic layer or an alignment layer on a light-transmitting substrate. In the production of the phase difference body, from the viewpoint of improving production efficiency and transportability, display production rate, etc., a relatively wide (1 m to 2 m) and thin plate-like body is formed, It is common to wind in a roll.

  However, when manufacturing a phase difference body corresponding to the widening of the display with an increase in screen size, the thinning of the display with a thin film, etc., the phase difference body is wound into a roll during or after the manufacturing process. In some cases, a black band appearing as a black band on the circumference of the blocking or roll-shaped body may be generated, which may cause a decrease in yield. Further, due to the blocking phenomenon, an abnormality occurs in the winding shape, and the roll-like phase difference body itself may be deformed. For this reason, the phase difference body itself cut out from the roll state cannot be used, or mounting on a display may be difficult.

  Therefore, it is an urgent task to prevent the occurrence of blocking and black bands in the production of the phase difference body, particularly in the winding process.

JP2007-304375A

The present inventor effectively prevents the generation of blocking and black bands in the winding process of the phase difference body by making the surface of the optically anisotropic layer constituting the phase difference body uneven in the present invention. In addition, it has been found that the addition of specific fine particles can effectively prevent foreign matters from being mixed into the optical functional layer in the liquid crystal device due to the attachment / detachment thereof. The present invention has been made based on such knowledge.
Therefore, the present invention is a phase difference body comprising a light-transmitting substrate and an optically anisotropic layer,
The optically anisotropic layer contains fine particles as a blocking inhibitor,
The surface of the optically anisotropic layer has an uneven shape.

In addition, the present invention can propose a method for producing a phase difference body comprising a light-transmitting substrate and an optically anisotropic layer,
Preparing the light-transmitting substrate and an optically anisotropic layer-forming composition comprising fine particles as a blocking inhibitor,
Applying the optically anisotropic layer forming composition to the light transmissive substrate to form an optically anisotropic layer having an uneven surface.

  According to the phase difference body and the method for manufacturing the same according to the present invention, in the manufacturing process of the phase difference body, the slipping property is improved, and at the same time, blocking and black band generation during winding of the phase difference body are effectively suppressed. In addition, it is possible to avoid mixing of foreign matters and to form an excellent liquid crystal structure.

I. Definition
Since the black luminance liquid crystal panel in principle displays light even when black is displayed, the parameter called “black luminance” is an indicator of how much black is displayed. The luminance is represented by a luminance value (cd / m2) measured when the panel is displayed black. In the present invention, “black luminance” means a visible light spectrometer (manufactured by JASCO Corporation, manufactured by Nitto Denko Co., Ltd., trade name: G1220DUN) in advance on the light receiving part side. Name: JSCO V-7100) is used to indicate the Y value displayed when measuring the phase difference body. In the present invention, the black luminance (Y) value can be appropriately determined for the purpose of use, but is 0.02 or less, preferably 0.015 or less. When the Y value is within the above numerical values, the contrast of the display panel is excellent when the polarizing plate is formed.

Average spacing Sm (μm), average inclination angle θa (degrees), and average roughness Ra (μm)
The optically anisotropic layer constituting the phase difference body according to the present invention has an uneven shape. Sm (μm) represents the average interval between the irregularities of the optically anisotropic layer, and θa (degree) represents the average inclination angle of the irregularities. These shall be defined in accordance with JIS B0601 1994 in the same way as the contents described in the instruction manual (1995, 07, 20 revision) of the surface roughness measuring instrument (model number: SE-3400 / manufactured by Kosaka Laboratory). Can do. θa (degrees) is a unit of angle, and Δa = tanθa is established when the inclination is expressed by an aspect ratio (Δa = tan θa) (the difference between the minimum and maximum portions of each unevenness (corresponding to the height of each convex portion) ) (Total / reference length). Here, the “reference length” is the same as the following measurement conditions, and is the measurement length (cut-off value λc) that is actually measured by the SE-3400.

When measuring the parameters (Sm, θa, Ra) representing the surface roughness of the optical stack according to measurements present invention, for example, using the surface roughness measuring instrument, the measurement conditions of a surface roughness measuring instrument JIS B0601 1994 The measurement can be performed by selecting the reference length and the evaluation length, and this measurement is preferable in the present invention.
1) Surface roughness detector stylus:
Model No./SE2555N (2μ standard) manufactured by Kosaka Laboratory Ltd. (tip radius of curvature 2μm / vertical angle: 90 degrees / material: diamond)
2) Measurement conditions of surface roughness measuring instrument:
Reference length (cutoff value λc of roughness curve):
1] 0.25, or 2] 0.8, or 3] 1.25, or 4] 2.5 mm
Evaluation length (reference length (cutoff value λc) × 5):
1] 1.25, or 2] 4.0, or 3] 6.25, or 4] 12.5 mm
Feeding speed of stylus: 0.1 to 0.5 mm / s
(When the reference length is 1] to 4], the evaluation length is correspondingly 1] to 4])

Unless otherwise specified, curable resin precursors such as resin monomers, oligomers, and prepolymers are collectively referred to as “resins”.

II. Retardant The present invention is a retarder comprising a light-transmitting substrate and an optically anisotropic layer. In this invention, a phase difference body may be formed in roll shape.
1) Optically anisotropic layer The optically anisotropic layer in the present invention comprises fine particles as an anti-blocking agent and a material having optical anisotropy (mainly a liquid crystal material). It has an uneven shape. The presence of the uneven shape effectively suppresses improvement in slipperiness, blocking, and generation of black bands in the manufacturing process of the phase difference body.
The uneven optical anisotropic layer on the surface has an uneven shape on the surface. This uneven shape is achieved by the presence of fine particles. In the present invention, the height of the convex structure in the concavo-convex shape is about 60 nm to 1,000 nm, preferably the upper limit is about 500 nm or less, as measured in the vertical direction from the base of the convex structure. Preferably, the upper limit is about 200 nm or less.

Sm, θa, Ra
The optically anisotropic layer according to the present invention preferably satisfies the following numerical values when the average interval of the unevenness of the unevenness is Sm, the average inclination angle of the unevenness is θa, and the average roughness of the unevenness is Ra. .
Sm is 0.01 μm or more and 5 μm or less, preferably the lower limit is 0.05 μm or more, and the upper limit is 3 μm or less.
θa is 0.1 degree or more and 1.2 degree or less, preferably the lower limit value is 0.3 degree or more and the upper limit value is 0.9 degree or less.
Ra is 1000 nm or less, preferably the lower limit is 3 nm or more, the lower limit is 500 nm or less, more preferably the lower limit is 5 nm or more, and the lower limit is 100 nm or less.

Fine particles The fine particles according to the present invention are used as antiblocking agents. The fine particles according to the present invention are preferably those which are not mixed into other members constituting the liquid crystal structure. In particular, fine particles that do not fall off even when the retardation is saponified are preferable. The shape of the fine particles may be spherical, for example, a true sphere, an ellipse, or an indefinite shape. The fine particles may be aggregated fine particles. In the present invention, the average particle diameter R (nm) of the fine particles is 10 nm or more and 1000 nm or less, preferably the upper limit is 500 nm or less, more preferably 200 nm or less, and preferably the lower limit is 20 nm or more. Those are preferred. This is because when the average particle diameter R of the fine particles is within the above range, an appropriate uneven shape can be formed and the blocking property is improved. The average particle diameter is the average particle diameter if the fine particles are monodisperse particles (particles having a single shape), and if the particles have a broad particle size distribution, The particle diameter of the most abundant particles is expressed as an average particle diameter. The particle diameter of the fine particles can be measured mainly by the Coulter counter method. In addition to this method, measurement can also be performed by laser diffraction or SEM photography.

  In the present invention, in 80% or more (preferably 90% or more) of the whole fine particles, the average particle size distribution of the fine particles is in the range of R ± 100 nm, preferably R ± 50 nm, more preferably R ± 30 nm. Those are preferred. By making the average particle size distribution of the fine particles within the above range, the uniformity of the uneven shape of the optically anisotropic layer can be improved. The fine particles may be first fine particles, and may further include a plurality of fine particles such as second fine particles, third fine particles or n-th fine particles (n is a natural number) having different average particle diameters. For example, for small particles with an average particle size R (nm) of the first fine particles of about 100 nm, irregular shapes can be efficiently formed with fine particles having a particle size distribution with an average particle size of 100 nm instead of monodispersed fine particles. It becomes possible to make it. When a plurality of fine particles having different average particle diameters are included, the average particle diameters of the second, third and nth fine particles are preferably in the same range as the fine particles (first fine particles).

[Aggregated fine particles]
In the present invention, among the fine particles, aggregated fine particles can be used. Aggregation type fine particles may be the same fine particle or may be composed of a plurality of fine particles having different average particle diameters. Accordingly, when a plurality of aggregated fine particles are used, (aggregated) second fine particles, (aggregated) third fine particles, or (aggregated) nth fine particles (n is a natural number) whose average particle size is different from the (aggregated) first fine particles. You may use what comprises. In the case of agglomerated fine particles, the secondary particle size is preferably within the above average particle size range.

In the present invention, when the average particle diameter of the first fine particles is R (nm) and the average particle diameter of the second fine particles is R ₂ (nm), the following formula:
0.25R (preferably 0.50) ≦ R ₂ ≦ 1.0R (preferably 0.70)
Those satisfying these conditions are preferred.

When R ₂ is within the above range, the composition is easily dispersed and the particles are not aggregated. Moreover, a uniform uneven | corrugated shape can be formed, without receiving to the influence of the wind at the time of floating in the drying process after application | coating. When the third fine particles and the n-th fine particles are present, it is preferable that the particle size relationship be the same as that of the first fine particles and the second fine particles. In this case, the second particles R, the third particle is R _2.

〔type〕
The fine particles (first, second, third, and nth fine particles) are not particularly limited, and inorganic and organic particles can be used, and preferably transparent. Specific examples of the fine particles formed of an organic material include plastic polymer beads. Plastic beads include styrene beads (refractive index 1.60), melamine beads (refractive index 1.57), acrylic beads (refractive index 1.49 to 1.535), acrylic-styrene beads (refractive index 1.54 to 1.58), benzoguanamine-formaldehyde beads, polycarbonate beads, polyethylene beads and the like. The plastic beads preferably have a hydrophobic group on the surface, and examples thereof include styrene beads. Inorganic fine particles include amorphous silica (SiO2), aluminum oxide, zirconia, titania, zinc oxide, germanium oxide, indium oxide, tin oxide, indium tin oxide (ITO), antimony oxide, cerium oxide, and other metal oxides Examples include fine particles.

  From the viewpoint of high hardness, silica / aluminum oxide is preferable. Further, in the present invention, although not so important, in order to obtain a relatively high refractive index layer, fine particles having a high refractive index when forming a film such as zirconia, titania, antimony oxide, etc. should be selected and used as appropriate. Can do.

[Chemically treated fine particles]
Moreover, in this invention, it is also possible to give the organic substance process etc. to the particle | grain surface. When the organic substance treatment is performed on the particle surface, a hydrophobic treatment is preferable. This organic treatment includes a method in which a compound is chemically bonded to the bead surface, and a physical method in which the voids in the composition forming the bead are infiltrated without being chemically bonded to the bead surface. Yes, you can use either one. In general, a chemical treatment method using an active group on a silica surface such as a hydroxyl group or a silanol group is preferably used from the viewpoint of treatment efficiency.

  Specific examples of the compound used for the treatment include silane-based, siloxane-based, and silazane-based agents that are highly reactive with the active group. For example, a linear alkyl single group substituted silicone agent such as methyltrichlorosilane, a branched alkyl monosubstituted silicone agent, or a polysubstituted linear alkyl silicone compound such as di-n-butyldichlorosilane or ethyldimethylchlorosilane, Examples thereof include substituted branched alkyl silicone compounds. Similarly, monosubstituted, polysubstituted siloxane agents and silazane agents having a straight chain alkyl group or a branched alkyl group can also be used effectively.

  Depending on the required function, those having a hetero atom, an unsaturated bond group, a cyclic bond group, an aromatic functional group or the like may be used at the terminal or intermediate part of the alkyl chain. In these compounds, since the alkyl group contained is hydrophobic, the surface of the material to be treated can be easily converted from hydrophilic to hydrophobic. High affinity can be obtained.

  In the case of using a mixture of a plurality of fine particles, in addition to those having different average particle sizes, the fine particles have different raw materials, different shapes, all different ones as described above. These can be appropriately selected and used while classifying the role of each fine particle.

[Fine particles with voids]
According to a preferred embodiment of the present invention, “fine particles having voids” may be used. In the present invention, the term “fine particles having voids” refers to a structure in which a gas is filled with gas and / or a porous structure containing gas, and the gas in the fine particle is compared with the original refractive index of the fine particle. It means fine particles whose refractive index decreases in inverse proportion to the occupation ratio. The present invention also includes fine particles capable of forming a nanoporous structure inside and / or at least part of the surface depending on the form, structure, aggregation state, and dispersion state of the fine particles inside the coating film. It is.

  As specific examples of the inorganic fine particles having voids, silica fine particles prepared by using the technique disclosed in Japanese Patent Application Laid-Open No. 2001-233611 are preferably exemplified. In addition, it may be silica fine particles obtained by the production methods described in JP-A-7-133105, JP-A-2002-79616, JP-A-2006-106714, and the like. Since silica fine particles having voids are easy to manufacture and have high hardness, the layer strength is improved when an optically anisotropic layer is formed by mixing with a binder. Specific examples of the organic fine particles having voids preferably include hollow polymer fine particles prepared by using the technique disclosed in JP-A-2002-80503.

  The fine particles capable of forming a nanoporous structure inside and / or at least part of the surface of the coating film are manufactured for the purpose of increasing the specific surface area in addition to the silica fine particles, and the packing column and the surface porosity Examples include sustained-release agents that adsorb various chemical substances on the mass part, porous fine particles used for catalyst fixation, or dispersions and aggregates of hollow fine particles intended to be incorporated into heat insulating agents and low dielectric agents. it can. Specifically, as a commercial product, an assembly of porous silica fine particles from the product names Nippil and Nipgel manufactured by Nippon Silica Industry Co., Ltd., and a structure in which silica fine particles manufactured by Nissan Chemical Industries, Ltd. are connected in a chain form. From the colloidal silica UP series (trade name), it is possible to use those within the preferred particle diameter range of the present invention.

  The average particle diameter of the “fine particles having voids” is 5 nm or more and 500 nm or less, preferably the lower limit is 8 nm or more and the upper limit is 300 nm or less, more preferably the lower limit is 10 nm or more and the upper limit is 200 nm or less.

[Colloidal silica]
In the present invention, colloidal silica can also be used. “Colloidal silica” means a colloidal solution in which silica particles in a colloidal state are dispersed in water or an organic solvent. The colloidal silica preferably has a particle size (diameter) of ultrafine particles of about 1 to 200 nm. In addition, the particle diameter of the colloidal silica in this invention is an average particle diameter by BET method. Specifically, the average particle diameter is calculated by measuring the surface area by the BET method and converting the particle as a true sphere.

  The colloidal silica is a known one, and commercially available ones include, for example, “methanol silica sol”, “MA-ST-M”, “IPA-ST”, “EG-ST”, “EG-ST-ZL”. ”,“ NPC-ST ”,“ DMAC-ST ”,“ MEK ”,“ XBA-ST ”,“ MIBK-ST ”(all products of Nissan Chemical Industries, Ltd., all trade names),“ OSCAL1132, ” “OSCAL1232”, “OSCAL1332”, “OSCAL1432”, “OSCAL1532”, “OSCAL1632”, “OSCAL1132” (above, products of Catalytic Chemical Industry Co., Ltd., all trade names) may be mentioned. it can.

  The addition amount of the fine particles is 0.10% by weight or more and 5.0% by weight or less with respect to the total amount of the optically anisotropic layer forming composition, preferably the lower limit is 0.2% by weight or more and the upper limit. The value is 3.0% by weight or less, more preferably the lower limit is 0.25% by weight or more, and the upper limit is 1.0% by weight or less. When the addition amount is within the above range, the slipping property in the manufacturing process is preferable, the black luminance of the manufactured retardation body is sufficient, and the contrast ratio can be set to a desired value.

[Reactive inorganic fine particles]
According to a preferred embodiment of the present invention, it is possible to use reactive inorganic fine particles, for example, inorganic fine particles that have at least a part of the surface coated with an organic component and have reactive functional groups introduced by the organic component on the surface. it can. Reactive inorganic fine particles have high hardness and are not easily crushed by pressure (external pressure) applied to the particles from the outside, and have excellent pressure resistance, and therefore have excellent scratch resistance. Further, when the surface of the optically anisotropic layer using reactive inorganic fine particles is saponified, the number of reactive inorganic fine particles eluted or dropped from the surface into the alkaline solution can be considerably reduced. It becomes possible to improve saponification property. As a result, a protective film for saponifying the optically anisotropic layer becomes unnecessary, and the number of processes and material costs can be reduced. Here, the “reactive inorganic fine particles” are inorganic fine particles in which at least a part of the surface of the inorganic fine particles as a core is coated with an organic component and the surface has a reactive functional group introduced by the organic component. is there. The reactive inorganic fine particles include those having two or more inorganic fine particles as a core per particle.

  The reactive functional group in this specification includes a photocurable functional group and a thermosetting functional group. The photocurable functional group means a functional group capable of curing a coating film by proceeding a polymerization reaction or a crosslinking reaction by light irradiation. For example, photo radical polymerization, photo cation polymerization, photo anion polymerization Examples of the polymerization reaction include those in which the reaction proceeds by a reaction mode such as addition polymerization or condensation polymerization that proceeds through photodimerization. “Thermosetting functional group” means a functional group capable of curing a coating film by causing a polymerization reaction or a crosslinking reaction to proceed between the same functional groups or other functional groups by heating, for example, , Hydroxyl groups, carboxyl groups, amino groups, epoxy groups, isocyanate groups, and the like. As the reactive functional group used in the present invention, particularly from the viewpoint of improving the hardness of the cured film, a polymerizable unsaturated group is preferably used, preferably a photocurable unsaturated group, particularly preferably an ionization. It is a radiation curable unsaturated group. Specific examples thereof include ethylenically unsaturated bonds such as (meth) acryloyl group, vinyl group and allyl group, and epoxy group.

Examples of the inorganic fine particles include metal oxides such as silica (SiO ₂ ), aluminum oxide, zirconia, titania, zinc oxide, germanium oxide, indium oxide, tin oxide, indium tin oxide (ITO), antimony oxide, and cerium oxide. Examples thereof include fine particles, fine metal fluoride particles such as magnesium fluoride and sodium fluoride. Metal fine particles, metal sulfide fine particles, metal nitride fine particles and the like may be used.

  As the reactive inorganic fine particles, it is preferable to use solid particles having no voids or porous structure inside the particles, rather than particles having voids or a porous structure inside the particles such as hollow particles. Since hollow particles have pores and porous structure inside the particles, the hardness is lower than that of solid particles, and the hollow particles have an apparent specific gravity (mass per unit volume averaged including the hollow part). ) Is smaller than solid particles. For this reason, it is preferable to use solid particles having high hardness and high specific gravity as compared with hollow particles.

  The reactive inorganic fine particles have at least a part of the surface coated with an organic component, and have a reactive functional group introduced by the organic component on the surface. Here, the “organic component” may be a component containing carbon. Further, as an aspect in which at least a part of the surface is coated with an organic component, for example, a compound containing an organic component such as a silane coupling agent reacts with a hydroxyl group present on the surface of the metal oxide fine particles, thereby In addition to the mode in which the organic component is bonded to the part, the mode in which the organic component is attached to the hydroxyl group present on the surface of the metal oxide fine particles by an interaction such as hydrogen bonding, or one or more inorganics in the polymer particle An embodiment containing fine particles is included.

The coating organic component covers almost the entire particle surface from the viewpoint of suppressing aggregation of inorganic fine particles and increasing the number of reactive functional groups on the surface of the inorganic fine particles to improve the hardness of the film. It is preferable. From such a viewpoint, the organic component covering the inorganic fine particles is preferably contained in the reactive inorganic fine particles in an amount of 1.00 × 10 ⁻³ g / m ² or more. In an aspect in which an organic component is attached to or bonded to the surface of the inorganic fine particle, the organic component covering the inorganic fine particle may be contained in the reactive inorganic fine particle at 2.00 × 10 ⁻³ g / m ² or more. More preferably, the reactive inorganic fine particles are particularly preferably contained in an amount of 3.50 × 10 ⁻³ g / m ² or more. In an embodiment in which inorganic fine particles are contained in the polymer particles, the organic component covering the inorganic fine particles is more preferably contained in the reactive inorganic fine particles in an amount of 3.50 × 10 ⁻³ g / m ² or more. It is particularly preferable that the reactive inorganic fine particles are contained in an amount of 5.50 × 10 ⁻³ g / m ² or more. The ratio of the organic component to be coated is usually determined by a thermogravimetric analysis from room temperature to normal 800 ° C. in air, for example, as a constant value of weight reduction when the dry powder is completely burned in air. be able to.

  For example, the amount of organic components per unit area can be determined by the following method. First, the value obtained by dividing the organic component weight by the inorganic component weight (organic component weight / inorganic component weight) is measured by differential thermogravimetry (DTG). Next, the volume of the whole inorganic component is calculated from the inorganic component weight and the specific gravity of the used inorganic fine particles. Further, assuming that the inorganic fine particles before coating are spherical, the volume and surface area per inorganic fine particle before coating are calculated from the average particle diameter of the inorganic fine particles before coating. Next, the number of reactive inorganic fine particles is obtained by dividing the volume of the entire inorganic component by the volume per inorganic fine particle before coating. Further, by dividing the organic component weight by the number of reactive inorganic fine particles, the amount of organic component per reactive inorganic fine particle A is obtained. Finally, by dividing the organic component weight per reactive inorganic fine particle by the surface area per inorganic fine particle before coating, the amount of organic component per unit area can be obtained.

  The average particle size of the reactive inorganic fine particles is 10 nm or more and 1000 nm or less, and particularly preferably 20 nm or more and 300 nm or less. By setting the average particle size of the reactive inorganic fine particles to 20 nm or more, an appropriate uneven shape can be formed, and the blocking property can be improved. The reactive inorganic fine particles preferably have a narrow particle size distribution and are monodispersed from the viewpoint of not significantly improving black luminance without impairing transparency. The average particle diameter of the reactive inorganic fine particles means a 50% particle diameter (d50 median diameter) when the particles in the solution are measured by a dynamic light scattering method and the particle diameter distribution is represented by a cumulative distribution. This average particle size can be measured using a Microtrac particle size analyzer manufactured by Nikkiso Co., Ltd. The reactive inorganic fine particles may be agglomerated particles. In the case of agglomerated particles, not only the primary particle size but also the secondary particle size may be within the above range.

As a method for preparing reactive inorganic fine particles having a reactive functional group introduced on the surface thereof, the organic component being coated on at least a part of the surface, depending on the reactive functional group to be introduced into the inorganic fine particles, Conventionally known methods can be appropriately selected and used. Among them, in the present invention, the organic component that is coated can be contained in the reactive inorganic fine particles in an amount of 1.00 × 10 ⁻³ g / m ² or more per unit area of the inorganic fine particles before coating. From the viewpoint of suppressing the aggregation of the fine particles and improving the hardness of the film, it is preferable to select and use any of the following inorganic fine particles (i) and (ii).

(I) Saturated or unsaturated carboxylic acid, acid anhydride, acid chloride, ester and acid amide corresponding to the carboxylic acid, amino acid, imine, nitrile, isonitrile, epoxy compound, amine, β-dicarbonyl compound, silane, And by dispersing inorganic fine particles in water and / or an organic solvent as a dispersion medium in the presence of one or more surface modification compounds having a molecular weight of 500 or less selected from the group consisting of metal compounds having functional groups. Inorganic fine particles having a reactive functional group on the surface.
(Ii) A compound containing a reactive functional group to be introduced into inorganic fine particles before coating, a group represented by the following chemical formula (1), and a silanol group or a group that generates a silanol group by hydrolysis is combined with metal oxide fine particles. Inorganic fine particles having reactive functional groups on the surface, obtained by
_{-Q 1 -C (= Q 2)} -NH- (1)
(In the above formula,
Q ₁ represents NH, O (oxygen atom), or S (sulfur atom);
Q ₂ represents O or S. )
Hereinafter, the reactive inorganic fine particles preferably used in the present invention will be described in order.

(I) Inorganic fine particles The surface modifying compound used for the reactive inorganic fine particles (i) is a carboxyl group, an acid anhydride group, an acid chloride group, an acid amide group, an ester group, an imino group, a nitrile group, C—H such as isonitrile group, hydroxyl group, thiol group, epoxy group, primary, secondary and tertiary amino group, Si—OH group, hydrolyzable residue of silane, or β-dicarbonyl compound It has a functional group such as an acid group that can chemically bond with a group present on the surface of the inorganic fine particles under dispersion conditions. The chemical bond here preferably includes a covalent bond, an ionic bond or a coordinate bond, but also includes a hydrogen bond. The coordination bond is considered to be complex formation. For example, acidic / base reaction, complex formation or esterification according to Bronsted or Lewis occurs between the functional group of the surface modifying compound and the group on the surface of the inorganic fine particle. The surface modification compound used in the reactive inorganic fine particles (i) can be used alone or in combination of two or more.

  The surface modifying compound is usually added to the surface modifying compound via the functional group in addition to at least one functional group (hereinafter referred to as a first functional group) capable of participating in chemical bonding with the surface group of the inorganic fine particles. After linking, it has molecular residues that impart new properties to the inorganic particulates. The molecular residue or a part thereof is hydrophobic or hydrophilic, and stabilizes, integrates, or activates the inorganic fine particles, for example. For example, examples of the hydrophobic molecular residue include an alkyl, aryl, alkaryl, aralkyl, or fluorine-containing alkyl group that causes inactivation or repulsion. Examples of the hydrophilic group include a hydroxy group, an alkoxy group, and a polyester group.

  A reactive functional group introduced on the surface may be adopted so that the reactive inorganic fine particles can react with the resin described later, and such a reactive functional group is appropriately selected according to the resin. As the reactive functional group, a polymerizable unsaturated group is suitably used, preferably a photocurable unsaturated group, and particularly preferably an ionizing radiation curable unsaturated group. Specific examples thereof include ethylenically unsaturated bonds such as (meth) acryloyl group, vinyl group and allyl group, and epoxy group. When a reactive functional group capable of reacting with a resin is contained in the molecular residue of the surface modification compound, the first functional group contained in the surface modification compound is reacted with the surface of the inorganic fine particles, thereby It is possible to introduce a reactive functional group capable of reacting with the resin on the surface of the reactive inorganic fine particles (i). For example, in addition to the first functional group, a surface modification compound further having a polymerizable unsaturated group is preferable. On the other hand, the surface of the reactive inorganic fine particles of (i) above is obtained by containing a second reactive functional group in the molecular residue of the surface modifying compound and using the second reactive functional group as a foothold. A reactive functional group capable of reacting with the resin may be introduced. For example, a group capable of hydrogen bonding (hydrogen bond forming group) such as a hydroxyl group and an oxy group is introduced as the second reactive functional group, and another hydrogen bond forming group introduced on the surface of the fine particles It is preferable that a reactive functional group capable of reacting with the binder component B is introduced by the reaction of the hydrogen bond forming group of the surface modification compound. That is, a compound having a hydrogen bond-forming group and a compound having a reactive functional group capable of reacting with the binder component B such as a polymerizable unsaturated group and a compound having a hydrogen bond-forming group are used in combination as the surface modification compound. A suitable example is given. Specific examples of the hydrogen bond-forming group indicate a functional group such as a hydroxyl group, a carboxyl group, an epoxy group, a glycidyl group, an amide group, or an amide bond. Here, the amide bond is meant to indicate a bond unit containing —NHC (O) and> NC (O) —. Among the hydrogen bond forming groups used in the surface modification compound of the present invention, among them, a carboxyl group, a hydroxyl group, and an amide group are preferable.

  The surface-modifying compound used in the reactive inorganic fine particles (i) has a molecular weight of 500 or less, more preferably 400, particularly 200. Since it has such a low molecular weight, it is presumed that the surface of the inorganic fine particles can be rapidly occupied and aggregation of the inorganic fine particles can be prevented. The surface modifying compound used in the reactive inorganic fine particles (i) is preferably a liquid under the reaction conditions for surface modification, and is preferably soluble or at least emulsifiable in a dispersion medium. Among these, it is preferable that the polymer is dissolved in the dispersion medium and uniformly distributed as discrete molecules or molecular ions in the dispersion medium.

  Saturated or unsaturated carboxylic acids have 1 to 24 carbon atoms, such as formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, acrylic acid, methacrylic acid, crotonic acid, citric acid, adipine Examples include acids, succinic acid, glutaric acid, oxalic acid, maleic acid, fumaric acid, itaconic acid and stearic acid, and the corresponding acid anhydrides, chlorides, esters and amides such as caprolactam. Further, when an unsaturated carboxylic acid is used, a polymerizable unsaturated group can be introduced.

Examples of preferred amines are those having the formula _Q 3 _-nNHn (n = 0,1 or 2), residues Q are independently 1 to 12, especially 1 to 6, particularly preferably is from 1 to 4 Represents alkyl having carbon atoms (e.g. methyl, ethyl, n-propyl, i-propyl and butyl), and aryl, alkaryl or aralkyl having 6 to 24 carbon atoms (e.g. phenyl, naphthyl, tolyl and benzyl) . Examples of preferred amines include polyalkyleneamines, and specific examples are methylamine, dimethylamine, trimethylamine, ethylamine, aniline, N-methylaniline, diphenylamine, triphenylamine, toluidine, ethylenediamine, and diethylenetriamine. .

  Preferred β-dicarbonyl compounds are those having 4 to 12, particularly 5 to 8 carbon atoms, such as diketones (such as acetylacetone), 2,3-hexanedione, 3,5-heptanedione, acetoacetic acid, acetoacetate. Examples include acetic acid-C1-C4-alkyl esters (such as acetoacetic acid ethyl ester), diacetyl, and acetonylacetone. Examples of amino acids include β-alanine, glycine, valine, aminocaproic acid, leucine and isoleucine.

  Preferred silanes are hydrolyzable organosilanes having at least one hydrolyzable group or hydroxy group and at least one non-hydrolyzable residue. Here, examples of the hydrolyzable group include a halogen, an alkoxy group, and an acyloxy group. As the non-hydrolyzable residue, a non-hydrolyzable residue having a reactive functional group and / or not having a reactive functional group is used. Silanes having at least partially organic residues substituted with fluorine may also be used.

As the silane used is not particularly limited, for _{example, CH 2 = CHSi (OOCCH 3} ) 3, CH 2 = CHSiCl 3, CH 2 = CHSi (OC 2 H 5) 3, CH 2 = CHSi (OC 2 H _{4 OCH 3) 3, CH 2} = CH-CH 2 -Si (OC 2 H 5) 3, CH 2 = CH-CH 2 -Si (OOCCH 3) 3, γ- glycidyloxypropyltrimethoxysilane (GPTS), γ-glycidyloxypropyldimethylchlorosilane, 3-aminopropyltrimethoxysilane (APTS), 3-aminopropyltriethoxysilane (APTES), N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- [ N '-(2'-aminoethyl) -2-aminoethyl] -3-aminopropyltrimethoxy Sisilane, hydroxymethyltrimethoxysilane, 2- [methoxy (polyethyleneoxy) propyl] trimethoxysilane, bis- (hydroxyethyl) -3-aminopropyltriethoxysilane, N-hydroxyethyl-N-methylaminopropyltriethoxysilane , 3- (meth) acryloxypropyltriethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, and the like.

As a metal compound which has a functional group, the metal compound of the metal M from 1st group III-V and / or 2nd group II-IV of an element periodic table is mentioned. Zirconium and titanium alkoxides, M (OR) ₄ (M = Ti, Zr), wherein part of the OR group is replaced by a complexing agent such as a β-dicarbonyl compound or a monocarboxylic acid. Can be mentioned. When a compound having a polymerizable unsaturated group (such as methacrylic acid) is used as a complexing agent, a polymerizable unsaturated group can be introduced.

  As the dispersion medium, water and / or an organic solvent is preferably used. A particularly preferred dispersion medium is distilled (pure) water. As the organic solvent, polar, nonpolar and aprotic solvents are preferred. Examples thereof include alcohols such as aliphatic alcohols having 1 to 6 carbon atoms (particularly methanol, ethanol, n- and i-propanol and butanol), ketones such as acetone and butanone, esters such as ethyl acetate; , Ethers such as tetrahydrofuran and tetrahydropyran; amides such as dimethylacetamide and dimethylformamide; sulfoxides and sulfones such as sulfolane and dimethylsulfoxide; and aliphatic (optionally halogenated) such as pentane, hexane and cyclohexane And hydrocarbons. These dispersion media can be used as a mixture. The dispersion medium preferably has a boiling point that can be easily removed by distillation (optionally under reduced pressure), and a solvent having a boiling point of 200 ° C. or lower, particularly 150 ° C. or lower is preferable.

  In the preparation of the reactive inorganic fine particles (i), the concentration of the dispersion medium is usually 40 to 90, preferably 50 to 80, particularly 55 to 75% by weight. The rest of the dispersion is composed of untreated inorganic fine particles and the surface modifying compound. Here, the weight ratio of the inorganic fine particles / surface modification compound is preferably 100: 1 to 4: 1, more preferably 50: 1 to 8: 1, and even more preferably 25: 1 to 10: 1. .

  The reactive inorganic fine particles (i) are preferably prepared at room temperature (about 20 ° C.) to the boiling point of the dispersion medium. Particularly preferably, the dispersion temperature is 50 to 100 ° C. The dispersion time depends in particular on the type of material used, but is generally from a few minutes to a few hours, for example 1 to 24 hours.

(Ii) Inorganic fine particles
The inorganic fine particles (ii) include a reactive functional group introduced into the inorganic fine particles before coating, a group represented by the following chemical formula (1), and a compound containing a silanol group or a group that generates a silanol group by hydrolysis, a core, It has a reactive functional group on the surface obtained by bonding with metal oxide fine particles as inorganic fine particles.
_{-Q 1 -C (= Q 2)} -NH- (1)
(In the chemical formula (1), Q ₁ represents NH, O (oxygen atom), or S (sulfur atom), and Q ₂ represents O or S.)
When the reactive inorganic fine particles (ii) are used, there are merits that the amount of organic components is increased, and dispersibility and film strength are further increased.

  First, a compound containing a reactive functional group to be introduced into inorganic fine particles before coating, a group represented by the above chemical formula (1), and a silanol group or a group that generates a silanol group by hydrolysis (hereinafter, reactive functional group-modified hydrolysis) In some cases, it may be referred to as a functional silane). In the reactive functional group-modified hydrolyzable silane, the reactive functional group desired to be introduced into the inorganic fine particles can be appropriately selected so that it can react with the resin. Suitable for introducing polymerizable unsaturated groups as described above.

In the reactive functional group-modified hydrolyzable silane, the group [—Q ₁ —C (═Q ₂ ) —NH—] represented by the chemical formula (1) is specifically [—O—C (═O). —NH—], [—O—C (═S) —NH—], [—S—C (═O) —NH—], [—NH—C (═O) —NH—], [—NH. -C (= S) -NH-] and [-S-C (= S) -NH-]. These groups can be used individually by 1 type or in combination of 2 or more types. Among them, from the viewpoint of thermal stability, [—O—C (═O) —NH—] group, [—O—C (═S) —NH—] group and [—S—C (═O) — It is preferable to use at least one NH-] group in combination. The group [—Q ₁ —C (= Q ₂ ) —NH—] represented by the chemical formula (1) generates an appropriate cohesive force due to hydrogen bonding between molecules, and has excellent mechanical strength when formed into a cured product. It is considered that properties such as adhesion to the substrate and heat resistance can be imparted.

  Examples of the group that generates a silanol group by hydrolysis include groups having an alkoxy group, an aryloxy group, an acetoxy group, an amino group, a halogen atom, etc. on the silicon atom. An oxysilyl group is preferred. A silanol group or a group that forms a silanol group by hydrolysis can be combined with the metal oxide fine particles by a condensation reaction or a condensation reaction that occurs following hydrolysis.

Preferable specific examples of the reactive functional group-modified hydrolyzable silane include, for example, compounds represented by the following chemical formula (2).
(OR ^a ) _m
｜ H H
R ^b _3-m —Si—R ^c —S—C—N—R ^d —N—C—O—R ^e — (Y ′) _n (2)
‖ ‖
O O

In the chemical formula (2), Ra and Rb may be the same or different, and are a hydrogen atom or a C1 to C8 alkyl group or aryl group, for example, methyl, ethyl, propyl, butyl, octyl, phenyl, xylyl group Etc. Here, m is 1, 2 or 3. Examples of the group represented by [(RaO) mRb ₃ -mSi-] include a trimethoxysilyl group, a triethoxysilyl group, a triphenoxysilyl group, a methyldimethoxysilyl group, and a dimethylmethoxysilyl group. Of these groups, a trimethoxysilyl group or a triethoxysilyl group is preferable.

Rc is a divalent organic group having a C1 to C12 aliphatic or aromatic structure, and may contain a chain, branched or cyclic structure. Examples of such an organic group include methylene, ethylene, propylene, butylene, hexamethylene, cyclohexylene, phenylene, xylylene, and dodecamethylene. Among these, preferred examples are methylene, propylene, cyclohexylene, phenylene and the like.
Rd is a divalent organic group, and is usually selected from divalent organic groups having a molecular weight of 14 to 10,000, preferably a molecular weight of 76 to 500. For example, chain polyalkylene groups such as hexamethylene, octamethylene, dodecamethylene; alicyclic or polycyclic divalent organic groups such as cyclohexylene and norbornylene; divalent groups such as phenylene, naphthylene, biphenylene and polyphenylene Aromatic group; and these alkyl group-substituted and aryl group-substituted products. In addition, these divalent organic groups may contain an atomic group containing an element other than carbon and hydrogen atoms, and include a polyether bond, a polyester bond, a polyamide bond, a polycarbonate bond, and a group represented by the chemical formula (1). Can also be included.

Re is an (n + 1) -valent organic group, and is preferably selected from a chain, branched or cyclic saturated hydrocarbon group and unsaturated hydrocarbon group.
Y ′ represents a monovalent organic group having a reactive functional group. The reactive functional group itself as described above may be used. For example, when the reactive functional group is selected from polymerizable unsaturated groups, (meth) acryloyl (oxy) group, vinyl (oxy) group, propenyl (oxy) group, butadienyl (oxy) group, styryl (oxy) group, ethynyl (Oxy) group, cinnamoyl (oxy) group, maleate group, (meth) acrylamide group and the like can be mentioned. N is preferably a positive integer of 1 to 20, more preferably 1 to 10, particularly preferably 1 to 5.

  For the synthesis of the reactive functional group-modified hydrolyzable silane used in the present invention, for example, a method described in JP-A-9-100111 can be used. That is, for example, when it is desired to introduce a polymerizable unsaturated group, (i) it can be carried out by an addition reaction of a mercaptoalkoxysilane, a polyisocyanate compound, and an active hydrogen group-containing polymerizable unsaturated compound capable of reacting with an isocyanate group. . Further, (b) the reaction can be carried out by a direct reaction between a compound having an alkoxysilyl group and an isocyanate group in the molecule and an active hydrogen group-containing polymerizable unsaturated compound. Furthermore, (c) it can also be directly synthesized by an addition reaction of a compound having a polymerizable unsaturated group and an isocyanate group in the molecule with mercaptoalkoxysilane or aminosilane.

  In the production of the reactive inorganic fine particles (ii), a method in which a reactive functional group-modified hydrolyzable silane is separately hydrolyzed and then mixed with the inorganic fine particles, followed by heating and stirring, or a reaction A method of hydrolyzing a functional functional group-modified hydrolyzable silane in the presence of inorganic fine particles, and in the presence of other components such as a polyunsaturated organic compound, a monounsaturated organic compound, a radiation polymerization initiator, A method for surface treatment of the inorganic fine particles can be selected, but a method in which the reactive functional group-modified hydrolyzable silane is hydrolyzed in the presence of the inorganic fine particles is preferable. When the reactive inorganic fine particles (ii) are produced, the temperature is usually 20 ° C. or higher and 150 ° C. or lower, and the treatment time is in the range of 5 minutes to 24 hours.

  In order to accelerate the hydrolysis reaction, an acid, salt or base may be added as a catalyst. Preferable examples of the acid include organic acids and unsaturated organic acids; examples of the base include tertiary amines or quaternary ammonium hydroxides. The amount of the acid or base catalyst added is 0.001 to 1.0% by weight, preferably 0.01 to 0.1% by weight, based on the reactive functional group-modified hydrolyzable silane.

  As the reactive inorganic fine particles, powdery fine particles that do not contain a dispersion medium may be used. However, it is preferable to use a fine particle in a solvent-dispersed sol because the dispersion step can be omitted and the productivity is high. The content of reactive inorganic fine particles is preferably 0 to 5% by weight, more preferably 0.25 to 1% by weight, based on the total solid content. When the content is in the above range, the unevenness of the optically anisotropic layer is sufficient and blocking can be effectively prevented, and the surface unevenness can be appropriately sized, so that the black luminance is greatly increased. Increase can be suppressed.

Optical anisotropy (liquid crystal material)
The optical anisotropy agent used for this invention will not be specifically limited if it is a material which can express desired retardation. In the present invention, an optical anisotropic agent exhibiting a nematic phase is preferably used. A nematic liquid crystal can be regularly arranged as compared with an optically anisotropic agent exhibiting another liquid crystal phase.

  As the optical anisotropic agent used in the present invention, a polymerizable optical anisotropic agent having a polymerizable functional group is preferably used. The polymerizable optically anisotropic agent can be polymerized with each other via a polymerizable functional group to fix the alignment state of the molecules, so that the mechanical strength of the optically anisotropic layer can be improved. In addition, it is possible to improve the orientation stability of the optical anisotropy and to effectively prevent fluctuations in Re and Rth due to changes with time and molecular orientation fluctuations in a high temperature environment.

  As the polymerizable functional group, various polymerizable functional groups that are polymerized by the action of ionizing radiation such as ultraviolet rays and electron beams, or heat are used. Representative examples of these polymerizable functional groups include radical polymerizable functional groups or cationic polymerizable functional groups. Further, representative examples of radically polymerizable functional groups include functional groups having at least one addition-polymerizable ethylenically unsaturated double bond, and specific examples include vinyl groups having or not having substituents, An acrylate group (generic name including an acryloyl group, a methacryloyl group, an acryloyloxy group, and a methacryloyloxy group) and the like can be given. Specific examples of the cationic polymerizable functional group include an epoxy group. In addition, examples of the polymerizable functional group include an isocyanate group and an unsaturated triple bond. In the present invention, among these polymerizable functional groups, a functional group having an ethylenically unsaturated double bond is preferably used from the viewpoint of the process.

  The polymerizable optical anisotropic agent may have one or more polymerizable functional groups described above. Further, a polymerizable optical anisotropic agent having a plurality of polymerizable functional groups and a polymerizable optical anisotropic agent having only one polymerizable functional group may be mixed and used. Specific examples of the polymerizable optical anisotropic agent include compounds described in JP-A-7-258638, JP-A-10-508882, and JP-A-2003-287623. it can. The matters disclosed therein form part of the present specification.

  In the present invention, it is preferable to use compounds represented by the following chemical formulas (1) to (10) as the polymerizable optical anisotropic agent.

  You may use an optically anisotropic agent 1 type or in mixture of 2 or more types. In the present invention, when two or more kinds of optical anisotropy agents are mixed and used, a polymerizable optical anisotropy agent and an optical anisotropy agent having no polymerizable functional group are mixed and used. Also good.

Other materials The optically anisotropic layer may contain other agents other than the optically anisotropic agent. Other materials are not particularly limited as long as they do not impair the alignment state of the optical anisotropy agent and the optical properties of the optical anisotropic layer, and may be appropriately selected and used depending on the application. Can do. Examples of other agents include a polymerization initiator, a polymerization inhibitor, a resin, a chiral agent, a plasticizer, a surfactant, and a silane coupling agent.

[Polymerization initiator / polymerization inhibitor]
When using a polymerizable optical anisotropic agent, it is preferable to use a polymerization initiator or a polymerization inhibitor. Examples of the polymerization initiator include benzophenone, methyl o-benzoylbenzoate, 4,4-bis (dimethylamine) benzophenone, 4,4-bis (diethylamine) benzophenone, α-amino acetophenone, 4,4-dichlorobenzophenone. 4-benzoyl-4-methyldiphenyl ketone, dibenzyl ketone, fluorenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, p-tert -Butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyldimethyl ketal, benzylmethoxyethyl acetal, benzoin Tyl ether, benzoin butyl ether, anthraquinone, 2-tert-butylanthraquinone, 2-amylanthraquinone, β-chloroanthraquinone, anthrone, benzanthrone, dibenzsuberone, methyleneanthrone, 4-azidobenzylacetophenone, 2,6-bis (p-azidobenzylidene ) Cyclohexane, 2,6-bis (p-azidobenzylidene) -4-methylcyclohexanone, 2-phenyl-1,2-butadion-2- (o-methoxycarbonyl) oxime, 1-phenyl-propanedione-2- ( o-ethoxycarbonyl) oxime, 1,3-diphenyl-propanetrione-2- (o-ethoxycarbonyl) oxime, 1-phenyl-3-ethoxy-propanetrione-2- (o-benzoyl) oxime Michler's ketone, 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone, naphthalenesulfonyl chloride Quinolinesulfonyl chloride, n-phenylthioacridone, 4,4-azobisisobutyronitrile, diphenyl disulfide, benzthiazole disulfide, triphenylphosphine, camphorquinone, N1717 manufactured by Adeka, carbon tetrabromide, tribromophenyl Examples include a combination of a photoreductive dye such as sulfone, benzoin peroxide, eosin, and methylene blue with a reducing agent such as ascorbic acid or triethanolamine.

  In this invention, these photoinitiators can be used 1 type or in combination of 2 or more types. Furthermore, when using the said photoinitiator, a photoinitiator adjuvant can be used together. Examples of such photopolymerization initiation assistants include tertiary amines such as triethanolamine and methyldiethanolamine, and benzoic acid derivatives such as ethyl 2-dimethylaminoethylbenzoate and ethyl 4-dimethylamidebenzoate. Yes, but not limited to these.

  Examples of the polymerization inhibitor include reactions of diphenylpicrylhydrazide, tri-p-nitrophenylmethyl, p-benzoquinone, p-tert-butylcatechol, picric acid, copper chloride, methylhydroquinone, methoquinone, tert-butylhydroquinone, etc. In view of storage stability, hydroquinone polymerization inhibitors are preferred, and methyl hydroquinone is particularly preferred.

[Resin etc.]
In the present invention, a resin or the like can be added. For example, the polyester prepolymer obtained by condensing a polyhydric alcohol and a monobasic acid or polybasic acid is reacted with (meth) acrylic acid. Polyester (meth) acrylate obtained: Polyurethane (meth) acrylate obtained by reacting a compound having a polyol group and two isocyanate groups with each other and then reacting the reaction product with (meth) acrylic acid; Bisphenol A type Epoxy resin, bisphenol F type epoxy resin, novolak type epoxy resin, polycarboxylic acid polyglycidyl ester, polyol polyglycidyl ether, aliphatic or cycloaliphatic epoxy resin, amino group epoxy resin, triphenolmethane type epoxy resin, dihydroxybenzene type Epoxy such as epoxy resin It includes photopolymerizable liquid crystal compound having an acryl group or a methacryl group or the like; and fat, (meth) photopolymerizable compound in epoxy (meth) acrylate obtained by reacting an acrylic acid.

[Chiral agent]
Examples of the arrangement state of the optical anisotropy agent in the optically anisotropic layer include a state where the optical anisotropy agent is oriented in parallel with respect to the light-transmitting substrate, A state in which the anisotropic agent is vertically oriented can be mentioned. The former liquid crystal structure is called a homogeneous structure (parallel alignment structure). By having such a structure, the retardation member used in the present invention can be optically imparted with properties as an A plate. Further, the latter liquid crystal structure is called a homeotropic structure (vertical alignment structure), and by having such a structure, the retardation member of the present invention can be imparted with properties as an optically positive C plate. it can.

  The arrangement state of the optical anisotropy agent may be a cholesteric arrangement state in which the optical anisotropy agent exhibits a regular helical structure. By having such an arrangement state, the property as an optically negative C plate can be imparted to the phase difference body used in the present invention.

  When the arrangement state of the optically anisotropic agent is changed to the cholesteric arrangement state, a chiral agent that induces a helical structure in the optically anisotropic layer is usually added. As such a chiral agent, a low molecular compound having axial asymmetry in the molecule is preferably used. As a chiral agent used for this invention, the compound represented by the following general formula (11), (12) or (13) can be mentioned, for example.

〔上記一般式（１１）又は（１２）中、
Ｒ_１は水素又はメチル基を示し、
ｃ及びｄは、アルキレン基の鎖長を示し、それぞれ個別に２〜１２の範囲の整数であり、好ましくは４〜１０の範囲であり、より好ましく６〜９の範囲であり、
Ｙは下記一般式（ｉ）〜（ｘｘｉｖ）の任意の一つであり、式（ｉ）、（ｉｉ）、（ｉｉｉ）、（ｖ）及び（ｖｉｉ）のいずれか一つであることが好ましい。〕

[In the above general formula (11) or (12),
R ₁ represents hydrogen or a methyl group,
c and d each represent the chain length of the alkylene group, and are each individually an integer in the range of 2 to 12, preferably in the range of 4 to 10, more preferably in the range of 6 to 9,
Y is any one of the following general formulas (i) to (xxiv), and is preferably any one of formulas (i), (ii), (iii), (v), and (vii). . ]

  The thickness of the optically anisotropic layer is not particularly limited, but is in the range of about 10 μm or less, preferably the lower limit is 0.1 μm or more and the upper limit is about 8 μm or less, more preferably the lower limit is 0.00. It is preferably 5 μm or more and the upper limit is about 5 μm or less.

  The optically anisotropic layer exhibits retardation, but such retardation can be arbitrarily adjusted according to the application. Preferably, Re at a wavelength of 550 nm is in the range of about 0.1 nm to 400 nm. This is because the range is necessary to optically compensate each mode of the liquid crystal panel.

  “Re” means the refractive index Nx in the slow axis direction (the direction with the highest refractive index) and the refraction in the fast axis direction (the direction with the smallest refractive index) in the in-plane direction of the optically anisotropic layer. It is a value represented by the formula of Re = (Nx−Ny) × d by the rate Ny and the thickness d of the optically anisotropic layer. “Rth” means the refractive index Nx in the slow axis direction (the direction with the largest in-plane refractive index) in the plane of the optically anisotropic layer, and the fast axis direction (the direction with the smallest in-plane refractive index). The refractive index Ny, the refractive index Nz in the thickness direction, and the thickness d of the optically anisotropic layer are values represented by the formula Rth = {(Nx + Ny) / 2−Nz} × d. These values can be measured by an automatic birefringence measuring apparatus (manufactured by Oji Scientific Instruments, trade name: KOBRA-21ADH).

According to a preferred aspect of the present invention, the phase difference body has a refractive index in the slow axis direction x of Nx, a refractive index in the fast axis direction y of Ny, and a thickness direction of z in the plane of the optically anisotropic layer. When the refractive index is Nz, the following general formula (I):
Nx> Ny ≧ Nz (I)
Those satisfying the above are preferable.

According to another preferred aspect of the present invention, the phase difference body is
In the plane of the optically anisotropic layer, when the refractive index in the slow axis direction x is Nx, the refractive index in the fast axis direction y is Ny, and the refractive index in the thickness direction z is Nz, the following general formula ( II):
Nx ≦ Ny <Nz (II)
Those satisfying the above are preferable.

According to still another preferred aspect of the present invention, the retardation member has a refractive index in the slow axis direction x of Nx and a refractive index in the fast axis direction y in the plane of the optically anisotropic layer. Ny, where Nz is the refractive index in the thickness direction z, the following general formula (III):
Nx≈Ny> Nz (III)
Those satisfying the above are preferable.

  In the present invention, the phase difference value can be appropriately determined for the purpose of use, but can be as follows. In the case of the optical compensation film for VA, the range of the retardation value is such that Re is about 0 nm to 10 nm and Rth is about 120 nm to 400 nm, or Re is about 40 nm to 70 nm and Rth is 150 nm. It is about 300 nm or less. In the case of the IPS optical compensation film, Re is about 60 nm to 140 nm and Rth is about −400 nm to 200 nm. Furthermore, in the present invention, in the case of the optical compensation film for TN, Re is about 120 nm to 280 nm and Rth is about 60 nm to 140 nm.

2) Light-transmitting substrate The light-transmitting substrate is transparent and has a function of supporting the optically anisotropic layer and other layers. Moreover, even if it is a light transmissive base material containing an additive as needed, it can be used conveniently.

  The transparency of the light-transmitting substrate used in the present invention is preferably such that the transmittance in the visible light region is 80% or more, preferably 90% or more. When the transmittance is in the above range, for example, when the retardation of the present invention is used as a viewing angle compensation film for a liquid crystal display device, it is possible to prevent the display luminance of the liquid crystal display device from being lowered. . The transmittance of the light transmissive substrate can be measured according to JIS K7361-1 (Testing method for total light transmittance of plastic transparent material).

  The light-transmitting substrate may be a flexible material having flexibility or a rigid material having no flexibility, and it is preferable to use a flexible material. By using a flexible material, the manufacturing process of the phase difference body of the present invention can be performed by rolling to roll (the substrate is in the form of a strip-shaped thin film (web, unrolled from the roll state wound on the core). Then, after that, it is possible to obtain a process that is wound again on the core again, so that a phase difference body with excellent productivity can be obtained.

  Examples of the material constituting the flexible material include various cellulose derivatives described later, norbornene polymers, cycloolefin polymers, polyolefin polymers such as amorphous polyolefins, acrylic polymers such as polymethyl methacrylate and modified acrylic polymers, polyvinyl alcohol, and polyimides. And polyester polymers such as polyarylate and polyethylene terephthalate, polysulfone, polyethersulfone, amorphous polyolefin, modified acrylic polymer, polystyrene, epoxy resin, polycarbonate, polyester, etc., cellulose derivatives or cycloolefin polymers Is preferred. This is because the cellulose derivative is particularly excellent in optical isotropy, and the cycloolefin polymer is excellent in durability.

  As the cellulose derivative, it is preferable to use a cellulose ester, and among the cellulose esters, it is preferable to use cellulose acylates. Cellulose acylates are widely produced industrially and are easily available.

  As the cellulose acylates, lower fatty acid esters having 2 to 4 carbon atoms are preferable. Such a lower fatty acid ester may contain only a single lower fatty acid ester, for example, cellulose acetate, and a plurality of fatty acid esters such as cellulose acetate butyrate and cellulose acetate propionate may be used. It may be included.

  In the present invention, cellulose acetate can be particularly preferably used among the lower fatty acid esters. Moreover, as a cellulose acetate, it is most preferable to use the triacetyl cellulose whose average acetylation degree is 57.5-62.5% (substitution degree: 2.6-3.0). Here, the degree of acetylation means the amount of bound acetic acid per unit mass of cellulose. The degree of acetylation can be determined by measurement and calculation of the degree of acetylation in ASTM: D-817-91 (testing method for cellulose acetate, etc.). In addition, the acetylation degree of the triacetyl cellulose which comprises a triacetyl cellulose film can be calculated | required by said method, after removing impurities, such as a plasticizer contained in a film.

  Examples of the cycloolefin polymer include a cycloolefin polymer (COP) or a cycloolefin copolymer (COC), and a cycloolefin polymer is preferable. Since the cycloolefin polymer has low moisture absorption and permeability, it is possible to stabilize the optical characteristics of the retardation body over time. Specific examples of the cycloolefin polymer include, for example, JSR Corporation, trade name: ARTON, Nippon Zeon Corporation, trade name ZEONOR, and the like.

The thickness of the light-transmitting substrate is not particularly limited, but is in the range of about 25 μm to 1000 μm, preferably the lower limit is 30 μm and the upper limit is about 100 μm. When the thickness of the light-transmitting substrate is within the above range, the performance as a support can be exhibited, the processing waste is reduced in the cutting process, etc., and the cutting blade can be prevented from being worn. It becomes. The light-transmitting substrate may be composed of a single layer or a plurality of layers, and may be composed of the same or different composition.
(The base material itself is drawn below.)

Stretching According to a preferred embodiment of the present invention, the light-transmitting substrate itself can be used even if it is stretched. The stretched light-transmitting substrate itself has alignment ability, and the liquid crystal material can be aligned along the stretching direction. Therefore, the stretched light-transmitting substrate can be obtained by stretching the above-described light-transmitting substrate.

  Moreover, it is also possible to use a commercially available stretched light-transmitting substrate, and it is possible to stretch a light-transmitting substrate made of various materials as required. Specifically, polycarbonate polymers, polyester polymers such as polyarylate and polyethylene terephthalate, polyimide polymers, polysulfone polymers, polyethersulfone polymers, polystyrene polymers, polyolefins such as polyethylene and polypropylene Film made of thermoplastic polymer such as polymer based polymer, polyvinyl alcohol polymer, cellulose acetate polymer, polyvinyl chloride polymer, polymethyl methacrylate polymer, or film made of liquid crystal polymer. it can. In the present invention, among them, a polyethylene terephthalate (PET) film is preferably used from the viewpoints of a wide range of stretch ratio and availability.

  The stretch ratio of the stretched film used in the present invention is not particularly limited as long as the stretch ratio is such that the orientation ability can be exhibited. Therefore, even if it is a biaxially stretched film, it can be used as long as the stretch ratio differs between the two axes.

3) Other layers In the present invention, in addition to the light-transmitting substrate and the optically anisotropic layer, other layers such as an alignment layer, a surface treatment layer, a shielding layer, and a stress relaxation layer are provided. There may be. In the present invention, the alignment layer will be described below.

Alignment layer The alignment layer has an alignment regulating force for the liquid crystal material contained in the optically anisotropic layer. As the alignment film used in the present invention, a light containing a rubbing film in which an alignment regulating force is expressed by rubbing the surface of a polymer film, or a photo-alignment material that expresses an alignment regulating force by a photo-alignment method. An alignment film is mentioned, and it is preferable to use a photo-alignment film. This is because by using the photo-alignment film, it becomes easy to adjust the alignment direction of the liquid crystal material, so that it is easy to obtain a phase difference body having a slow axis in an arbitrary direction. In addition, the rubbing film may cause a bright spot defect when, for example, the phase difference body of the present invention is used in a liquid crystal display device due to dust generated in the rubbing treatment for expressing the alignment regulating force. However, since the photo-alignment film can express the alignment regulating force in a non-contact manner by irradiating light, there are few such problems. The “photo-alignment method” is a method for expressing the alignment regulating force (anisotropy) of the alignment layer by irradiating the alignment layer with light having an arbitrary polarization state (polarized light).

  Photoalignment materials are largely divided into photoisomerization materials that reversibly change the alignment regulation force by changing only the molecular shape by irradiating polarized light, and photoreactive materials that change the molecule itself by irradiating polarized light. Can be separated. In the present invention, it is more preferable to use a photoreactive material. The photoreactive material is a material that reacts with polarized light and reacts with molecules to develop an orientation regulating force. Therefore, it becomes possible to irreversibly develop an orientation regulating force, and the stability over time of the orientation regulating force is achieved. Is excellent.

  The photoreactive material can be further classified according to the type of reaction caused by polarized light irradiation. Specifically, a photodimerization type material that develops an alignment regulation force by causing a photodimerization reaction, a photodegradable material that produces an orientation regulation force by producing a photodecomposition reaction, an orientation regulation by producing a photobinding reaction It can be divided into a photocoupled material that expresses force, and a photolytic-coupled material that develops alignment regulation force by causing a photodecomposition reaction and a photocoupled reaction. In the present invention, it is more preferable to use a photodimerization type material.

  The photodimerization-type material is not particularly limited as long as it is a material that can exhibit an orientation regulating force by causing a photodimerization reaction. Especially in this invention, it is preferable that the wavelength of the light which produces a photodimerization reaction exists in the range of 200 nm-300 nm.

  Examples of the photodimerization type material include cinnamate, coumarin, benzylidenephthalimidine, benzylideneacetophenone, diphenylacetylene, stilbazole, uracil, quinolinone, maleimide, or a polymer having a cinnamylidene acetic acid derivative, cinnamate, or , A polymer having at least one of coumarin, a polymer having cinnamate and coumarin are preferably used. Specific examples of such a photodimerization type material include compounds described in JP-A-9-118717, JP-A-10-506420, and JP-A-2003-505561. As cinnamate and coumarin, those represented by the following general paper formulas Ia and Ib are preferably used.

〔上記式中、
Ａは、ピリミジン−２，５−ジイル、ピリジン−２，５−ジイル、２，５−チオフェニレン、２，５−フラニレン、１，４−もしくは２，６−ナフチレンを表すか、非置換であるか、フッ素、塩素または炭素原子１〜１８個の環式、直鎖状もしくは分岐鎖状アルキル残基（非置換であるか、フッ素、塩素によって一または多置換されており、１個以上の隣接しない−ＣＨ₂−基が独立して基Ｃによって置換されていてもよい）によって一または多置換されているフェニレンを表し、
Ｂは、水素原子を表すか、第二の物質、たとえばポリマー、オリゴマー、モノマー、光活性ポリマー、光活性オリゴマーおよび／または光活性モノマーもしくは表面と反応または相互作用することができる基を表し、
Ｃは、−Ｏ−、−ＣＯ−、−ＣＯ−Ｏ−、−Ｏ−ＣＯ−、−ＮＲ¹−、−ＮＲ¹−ＣＯ−、−ＣＯ−ＮＲ1−、−ＮＲ¹−ＣＯ−Ｏ−、−Ｏ−ＣＯ−ＮＲ¹−、−ＮＲ¹−ＣＯ−ＮＲ¹−、−ＣＨ＝ＣＨ−、−Ｃ≡Ｃ−、−Ｏ−ＣＯ−Ｏ−および−Ｓｉ（ＣＨ₃）₂−Ｏ−Ｓｉ（ＣＨ₃）₂−（Ｒ¹は水素原子または低級アルキルを表す）から選択される基を表し、
Ｄは、−Ｏ−、−ＣＯ−、−ＣＯ−Ｏ−、−Ｏ−ＣＯ−、−ＮＲ¹−、−ＮＲ¹−ＣＯ−、−ＣＯ−ＮＲ¹−、−ＮＲ¹−ＣＯ−Ｏ−、−Ｏ−ＣＯ−ＮＲ¹−、−ＮＲ¹−ＣＯ−ＮＲ¹−、−ＣＨ＝ＣＨ−、−Ｃ≡Ｃ−、−Ｏ−ＣＯ−Ｏ−および−Ｓｉ（ＣＨ₃）²−Ｏ−Ｓｉ（ＣＨ₃）₂−（Ｒ¹は水素原子または低級アルキルを表す）から選択される基、芳香族基または脂環式基を表し、
Ｓ₁およびＳ₂は、互いに独立して、単結合またはスペーサー単位、たとえば炭素原子１〜４０個の直鎖状もしくは分岐鎖状アルキレン基（非置換であるか、フッ素、塩素によって一または多置換されており、１個以上の隣接しない−ＣＨ₂−基が独立して基Ｄによって置換されていてもよいが、酸素原子が互いに直接的には結合していない）を表し、
Ｑは、酸素原子または−ＮＲ¹−（Ｒ¹は水素原子または低級アルキルを表す）を表し、
ＸおよびＹは、互いに独立して、水素、フッ素、塩素、シアノ、炭素原子１〜１２個のアルキル（場合によってはフッ素によって置換されており、場合によっては１個以上の隣接しない−ＣＨ₂−基が−Ｏ−、−ＣＯ−Ｏ−、−Ｏ−ＣＯ−および／または−ＣＨ＝ＣＨ−によって置換されている）を表す。〕

[In the above formula,
A represents pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thiophenylene, 2,5-furylene, 1,4- or 2,6-naphthylene, or unsubstituted. Or a cyclic, linear or branched alkyl residue of 1 to 18 carbon atoms (unsubstituted or mono- or polysubstituted by fluorine or chlorine, one or more adjacent Represents a phenylene which is mono- or polysubstituted by a —CH ₂ — group which may be independently substituted by the group C),
B represents a hydrogen atom or a group capable of reacting or interacting with a second substance, such as a polymer, oligomer, monomer, photoactive polymer, photoactive oligomer and / or photoactive monomer or surface;
C is, -O -, - CO -, - CO-O -, - O-CO -, - NR 1 -, - NR 1 -CO -, - CO-NR1 -, - NR 1 -CO-O-, —O—CO—NR ¹ —, —NR ¹ —CO—NR ¹ —, —CH═CH—, —C≡C—, —O—CO—O— and —Si (CH ₃ ) ₂ —O—Si Represents a group selected from (CH ₃ ) ₂ — (R ¹ represents a hydrogen atom or lower alkyl);
D represents —O—, —CO—, —CO—O—, —O—CO—, —NR ¹ —, —NR ¹ —CO—, —CO—NR ¹ —, —NR ¹ —CO—O—. , —O—CO—NR ¹ —, —NR ¹ —CO—NR ¹ —, —CH═CH—, —C≡C—, —O—CO—O— and —Si (CH ₃ ) ² —O—. A group selected from Si (CH ₃ ) ₂ — (R ¹ represents a hydrogen atom or lower alkyl), an aromatic group or an alicyclic group;
S ₁ and S ₂ are independently of each other a single bond or a spacer unit, for example a linear or branched alkylene group of 1 to 40 carbon atoms (unsubstituted or mono- or polysubstituted by fluorine, chlorine And one or more non-adjacent —CH ₂ — groups may be independently substituted by the group D, but the oxygen atoms are not directly bonded to each other),
Q represents an oxygen atom or —NR ¹ — (R ¹ represents a hydrogen atom or lower alkyl);
X and Y are independently of each other hydrogen, fluorine, chlorine, cyano, alkyl of 1 to 12 carbon atoms (optionally substituted by fluorine and optionally one or more non-adjacent —CH ₂ — Group is substituted by -O-, -CO-O-, -O-CO- and / or -CH = CH-). ]

In the present invention, among the cinnamates represented by the above formula and coumarins, those described in JP-T-2004-536185 are preferably used.
When using a photo-alignment film, other materials may be included in addition to the photo-alignment material. As such other materials, monomers or oligomers having one or more functional groups are usually used. Examples of such a monomer or oligomer include monofunctional monomers having an acrylate functional group (for example, reactive ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone) and many others. Functional monomers (for example, polymethylolpropane tri (meth) acrylate, hexanediol (meth) acrylate, triethylene (polypropylene) glycol diacrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri ( (Meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate And isocyanuric acid poly (meth) acrylate (for example, isocyanuric acid EO diacrylate)) and bisphenol fluorene derivatives (for example, bisphenoxyethanol full orange acrylate, bisphenol full orange epoxy acrylate), etc. be able to.

  The monomer or oligomer is preferably a polymerizable liquid crystal material. When a polymerizable liquid crystal material is included in the optically anisotropic layer, the polymerizable liquid crystal material preferably includes the same type of polymerizable liquid crystal material as included in the optically anisotropic layer. In the case of using a method in which the monomer or oligomer is rolled when the alignment layer is laminated on the light-transmitting substrate as a method for producing the retardation member used in the present invention, the alignment layer is at room temperature (20 It is preferable to use a material that becomes solid at ˜25 ° C.). In this case, it is preferable to use a monomer or oligomer that is solid at room temperature (20 to 25 ° C.). Thereby, even when it rolls at the time of alignment layer being laminated | stacked on the light transmissive base material, it can prevent that the blocking resulting from sticking an alignment layer on the back surface of a light transmissive base material arises.

  The content of the monomer or oligomer is not particularly limited as long as it is within a range in which the alignment layer and the optically anisotropic layer can be adhered with desired strength. The range of 0.01 to 3 times the mass of the photoreactive material is preferable, and the range of 0.05 to 1.5 times is particularly preferable. When the content is in the above range, the alignment layer and the optically anisotropic layer can be adhered with a desired strength, and the alignment regulating force of the alignment layer can be sufficiently exhibited. Become. The thickness of the alignment layer is preferably in the range of about 0.01 μm to 0.5 μm, preferably the lower limit is 0.02 μm and the upper limit is about 0.2 μm.

  A solvent can be used as the composition for forming an alignment layer. The solvent is not particularly limited as long as it can dissolve the photo-alignment material and the monomer or oligomer at a desired concentration. For example, hydrocarbon solvents such as benzene and hexane, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, ether solvents such as tetrahydrofuran and 1,2-dimethoxyethane, alkyl halide solvents such as chloroform and dichloromethane, Ester solvents such as methyl acetate, ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, amide solvents such as N, N-dimethylformamide, sulfoxide solvents such as dimethyl sulfoxide, anan solvents such as cyclohexane, methanol, Examples of the alcohol solvent include ethanol and propanol, but are not limited thereto. Further, the solvent used in the present invention may be one kind or a mixed solvent of two or more kinds of solvents.

II. Method for producing phase difference body The method for producing a phase difference body of the present invention comprises forming an optically anisotropic layer and other layers on a light-transmitting substrate. The outline of the production method according to the present invention will be described below.

(1) Material preparation step A light-transmitting substrate, an optically anisotropic layer, and other layer forming compositions are prepared.
(2) Optically anisotropic layer and other layer forming steps After forming the coating film of the optically anisotropic layer forming composition, the liquid crystal material contained in the coating film is aligned to form the optically anisotropic layer. Form. As a method of aligning the liquid crystal material in this step, a method of heating the coating film to a temperature higher than the liquid crystal layer forming temperature of the liquid crystal material is usually used. In addition, an alignment layer can be formed before forming the optically anisotropic layer. In the present invention, the alignment layer cures the monomer or oligomer while cutting the absorption wavelength of the alignment film composition, and then irradiates ultraviolet rays having an arbitrary polarization state to express the alignment regulating force. Thus, an alignment layer can be obtained.

  Specific examples of the method of coating the optically anisotropic layer or other layer forming composition on the light transmissive substrate include a gravure coating method, a reverse coating method, a knife coating method, a dip coating method, Examples thereof include a spray coating method, an air knife coating method, a roll coating method, a printing method, a curtain coating method, a die coating method, a casting method, a bar coating method, an extrusion coating method, and an E-type coating method.

  As a drying method, a commonly used drying method such as a heat drying method, a vacuum drying method, a gap drying method, or the like can be used. In addition, the drying method in the present invention is not limited to a single method, and a plurality of drying methods may be employed, for example, by changing the drying method sequentially according to the amount of solvent remaining.

(3) Stretching treatment In the present invention, the light-transmitting substrate may be stretched after forming the optically anisotropic layer and other layers. In the present invention, in addition to using a stretched light-transmitting substrate, it is possible to stretch the polarizer after constituting the polarizer, which is more preferable. Since the light-transmitting substrate on which each layer is formed is stretched, there is an advantage that it is easy to stabilize the refractive index anisotropy by reducing variations in the degree of expression of refractive index anisotropy due to variations in stretching conditions. Have.

  In this invention, it has the extending process which extends the said polymer film after the said drying process, and also the said refractive index anisotropic material which penetrate | infiltrated in the said polymer film is fixed after the said extending process. You may have an immobilization process. Thus, when extending | stretching before fixing the said refractive index anisotropic material, it is possible to enlarge the change of the retardation value of retardation film in an extending | stretching process.

  Moreover, in this invention, you may have the application | coating process which apply | coats the said coating liquid for phase difference strengthening area | region formation after the extending | stretching process of extending | stretching the said polymer film. Even in such a case, it is possible to reinforce both the in-plane direction and the thickness direction retardation value, and by applying and infiltrating a refractive index anisotropic material after stretching, than that stretched after coating. In the high-temperature and high-humidity test to be performed later, there is a merit that the stretching return is reduced.

III. Physical properties and application of phase difference body The phase difference body can be formed in the form of a thin film (film), a plate, a sheet or the like. The thickness of the phase difference body is in the range of about 30 μm to 200 μm, preferably the lower limit is 30 μm or more and the upper limit is about 100 μm.

  The chromatic dispersion of Re in the phase difference body may be a reverse dispersion type in which the Re value decreases as the wavelength becomes shorter, or a forward dispersion type in which the Re value increases as the wavelength becomes shorter, or the Re value. May be a flat type having no wavelength dependency.

  Examples of the retardation member according to the present invention include an optical compensation film (for example, a viewing angle compensation film), an elliptically polarizing plate, and a brightness enhancement plate used for a liquid crystal display device. Especially, the phase difference body of this invention can be used suitably as an optical compensation film for the viewing angle dependency improvement of a liquid crystal display device.

EXAMPLES The contents of the present invention will be described in detail by the following examples, but the contents of the present invention should not be construed as being limited by the following examples.

Preparation of reactive inorganic fine particles
Reactive inorganic fine particles 1
(1) Surface adsorbed ion removal Water-dispersed colloidal silica (Snowtex ZL, trade name, manufactured by Nissan Chemical Industries, Ltd., pH 9 to 10) having a particle diameter of 90 nm is exchanged with a cation exchange resin (Diaion SK1B, Mitsubishi Chemical Corporation). Ion exchange is performed for 3 hours using 400 g, and then ion exchange is performed for 3 hours using 200 g of anion exchange resin (Diaion SA20A, manufactured by Mitsubishi Chemical Corporation), followed by washing and solid content concentration of 20 An aqueous dispersion of wt% inorganic fine particles was obtained. At this time, the Na ₂ O content of the aqueous dispersion of inorganic fine particles was 7 ppm for each inorganic fine particle.
(2) Surface treatment (introduction of monofunctional monomer)
150 g of isopropanol, 4.0 g of 3,6,9-trioxadecanoic acid, and 4.0 g of methacrylic acid are added to 10 g of the aqueous dispersion of inorganic fine particles subjected to the treatment of (1) above and stirred for 30 minutes. Mixed. The obtained mixed liquid was stirred while being heated at 60 ° C. for 5 hours to obtain an inorganic fine particle dispersion liquid in which methacryloyl groups were introduced on the surface of the inorganic fine particles. Distilled water and isopropanol were distilled off using a rotary evaporator to the obtained inorganic fine particle dispersion, and while adding methyl ethyl ketone so as not to dry, the final residual water and isopropanol were 0.1% by weight, A silica-dispersed methyl ethyl ketone solution having a solid content of 50% by weight was obtained. The reactive inorganic fine particles 1 thus obtained had an average particle size of d50 = 93 nm as a result of measurement with a Microtrac particle size analyzer manufactured by Nikkiso Co., Ltd. The amount of the organic component covering the surface of the inorganic fine particles was 4.05 × 10 ⁻³ g / m ² as a result of measurement by thermogravimetric analysis.

Reactive inorganic fine particles 2
Surface treatment was performed in the same manner as the preparation of the reactive inorganic fine particles 1 except that methacrylic acid was changed to dipentaerythritol pentaacrylate (SR399, trade name, manufactured by Sartomer Co., Ltd.). The reactive inorganic fine particles 2 thus obtained had an average particle diameter of d50 = 93 nm as a result of measurement by the particle size analyzer. The amount of the organic component covering the surface of the inorganic fine particles was 3.84 × 10 ⁻³ g / m ² as a result of measurement by thermogravimetric analysis.

Reactive inorganic fine particles 3
To a solution consisting of 7.8 parts of mercaptopropyltrimethoxysilane and 0.2 part of dibutyltin dilaurate in dry air, 20.6 parts of isophorone diisocyanate was added dropwise at 50 ° C. over 1 hour and then at 60 ° C. Stir for 3 hours. To this, 71.4 parts of pentaerythritol triacrylate was added dropwise at 30 ° C. over 1 hour, and then heated and stirred at 60 ° C. for 3 hours to obtain a compound. Next, 88.5 parts (solid content 26.6 parts) of methanol silica sol (manufactured by Catalyst Chemicals Co., Ltd., trade name, OSCAL series, methanol dispersion, number average particle size 45 nm) under the nitrogen stream was synthesized as described above. A mixed solution of 8.5 parts of the compound and 0.01 parts of p-methoxyphenol was stirred at 60 ° C. for 4 hours. Subsequently, 3 parts of methyltrimethoxysilane as compound (2) is added to this mixed solution, and after stirring for 1 hour at 60 ° C., 9 parts of methyl orthoformate is added, and further heated and stirred at the same temperature for 1 hour. Thus, crosslinkable inorganic fine particles were obtained. The reactive inorganic fine particles 3 thus obtained had an average particle diameter of d50 = 49 nm as a result of measurement by the particle size analyzer. Moreover, the amount of organic components covering the surface was 7.08 × 10 ⁻³ g / m ² as a result of measurement by thermogravimetric analysis.

Reactive inorganic fine particles 4
(1) Removal of surface adsorbed ions When water-dispersed colloidal silica having a particle size of 20 nm was purified by the same production method as that for reactive inorganic fine particles 1, it had an average particle size of d50 = 23 nm. The amount of the organic component covering the surface of the inorganic fine particles was 4.00 × 10 ⁻³ g / m ² as a result of measurement by thermogravimetric analysis.

Reactive inorganic fine particles 5
(1) Removal of surface adsorbed ions When water-dispersed colloidal silica having a particle size of 300 nm was purified by the same production method as reactive inorganic fine particles 1, it had an average particle size of d50 = 350 nm. The amount of the organic component covering the surface of the inorganic fine particles was 5.00 × 10 ⁻³ g / m ² as a result of measurement by thermogravimetric analysis.

Production of phase difference body
Example 1
A radical polymerization initiator (trade name: Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) is added to a solution obtained by dissolving 20% by weight of a photopolymerizable nematic liquid crystal in cyclohexanone. A composition for forming an optically anisotropic layer was prepared by adding 0.5% by weight to the liquid crystal solid content. This optically anisotropic layer forming composition was coated on the surface of a light-transmitting substrate made of a TAC film (manufactured by Fuji Film Co., Ltd., trade name: TF80UL) with a coating amount of 2.5 g / d after drying by bar coating. After coating to m ² and heating at 50 ° C. for 4 minutes to remove the solvent, the coated surface is irradiated with ultraviolet rays of 100 mJ / cm ² to produce a retardation film with the photopolymerizable liquid crystal fixed. did.

Example 2
A retardation film was obtained in the same manner as in Example 1 except that 0.5% by weight of the reactive inorganic fine particles 2 was added in place of the reactive inorganic fine particles 1.

Example 3
A retardation film was obtained in the same manner as in Example 1 except that 0.5% by weight of the reactive inorganic fine particles 3 was added in place of the reactive inorganic fine particles 1.

Example 4
The retardation film produced in Example 1 was uniaxially stretched in the in-plane direction while being heated at 160 ° C. so as to have a stretching ratio of 1.2 times by a stretching experiment apparatus, thereby preparing a retardation film.

Example 5
A radical polymerization initiator (trade name: Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) is added to a solution obtained by dissolving 20% by weight of a photopolymerizable liquid crystal exhibiting homeotropic alignment in toluene, and then reacted. A composition for forming an optically anisotropic layer was prepared by adding 0.3% by weight of the inorganic fine particles 1 to the solid content of the liquid crystal. And the coating amount after drying this barium coating on the surface of the light-transmitting base material which consists of this composition for optically anisotropic layer formation from a TAC film (Fuji Film Co., Ltd. brand name: TF80UL) is 1. Retardation film which fixed the said photopolymerizable liquid crystal by apply | coating so that it might become 5 g / m < ² >, heating at 50 degreeC for 4 minutes, removing a solvent, and irradiating an ultraviolet-ray to an application surface 100mJ / cm < ² >. Was made.

Comparative Example 1
A retardation film was produced in the same manner as in Example 1 except that the composition for forming an optically anisotropic layer was used without adding the reactive inorganic fine particles 1.

Comparative Example 2
Using the retardation film of Comparative Example 1, the same stretching as in Example 4 was performed.

Comparative Example 3
The same coating as in Example 5 was performed using the retardation film of Comparative Example 2.

Comparative Example 4
A retardation film was obtained in the same manner as in Example 1 except that the reactive inorganic fine particles 4 were added in an amount of 0.5% by weight based on the solid content.

Comparative Example 5
A retardation film was obtained in the same manner as in Example 1 except that the reactive inorganic fine particles 1 were added in an amount of 1.0% by weight based on the solid content.

Comparative Example 6
A retardation film was obtained in the same manner as in Example 1 except that 0.5% by weight of the reactive inorganic fine particles 5 was added to the solid content.

The following evaluation tests were performed on the retardation films of the evaluation test example and the comparative example, and the results are shown in Table 1 below.

Evaluation 1: Bonding evaluation test The surface of the retardation film having the uneven shape and the surface of the light-transmitting substrate on the opposite side were bonded between circular metals of φ1.5 cm, and 3 kg / cm ² . After being left at room temperature for 5 days (120 hr) under a weighted condition, it was peeled off, and the state was evaluated according to the following evaluation criteria. This test condition is equivalent to the load applied when a light-transmitting substrate having a specific gravity of about 0.8 to 1.2 and a film thickness of about 40 to 100 μm is present in the center of a 4000 M roll. It is a numerical value.
Evaluation Criteria Evaluation A: No trace of uneven shape was confirmed on the surface of the light-transmitting substrate.
Evaluation (circle): The trace of uneven | corrugated shape was confirmed by the area of less than 1/3 on the surface of the transparent base material.
Evaluation (triangle | delta): The trace of uneven | corrugated shape was confirmed in the surface of the transparent base material in the area of 1/3 or more and less than 2/3.
Evaluation x: Irregular traces were confirmed on the entire surface of the light-transmitting substrate.

Evaluation 2, 3: Re, Rth measurement About the retardation film, Nx, Ny, Nz were measured using an automatic birefringence measuring device (manufactured by Oji Scientific Instruments Co., Ltd., trade name: KOBRA-21ADH). The value of Rth was obtained by introducing it into the following formula.
(1) Re = (Nx−Ny) × d
(2) Rth = {(Nx + Ny) / 2−Nz} × d

Evaluation 4: Black Luminance Measurement Evaluation Black luminance measurement was performed using a visible light spectrometer (Nippon Bunko Co., Ltd.) in which a polarizing plate (manufactured by Nitto Denko Corporation, trade name: G1220DUN) was previously set so as to be crossed Nicol on the light receiving side. ), Product name: JASCO V-7100) (Y value at this time is set to 0.005), and the phase difference body is between the polarizing plate and the projector, and the optical laminate is in-plane method. The Y value when the linear direction is set to coincide with the incident direction is shown.

Evaluation 5: Height of the concavo-convex structure The concavo-convex height was measured with an atomic force microscope (manufactured by Veeco, trade name: AFM Nanoscope V Multimode) under the following conditions, and the height of the optical laminate surface was evaluated. Represents the difference between the maximum and minimum values.
AFM measurement condition measurement method: tapping mode Scanning range: 1 μm ² , 5 μm ²
Scan rate: 1.1Hz
Number of pixels: 512 × 512

Claims (9)

A phase difference body comprising a light-transmitting substrate and an optically anisotropic layer,
The optically anisotropic layer contains fine particles as a blocking inhibitor,
A phase difference body, wherein the surface of the optically anisotropic layer has an uneven shape. In the plane of the optically anisotropic layer, when the refractive index in the slow axis direction x is Nx, the refractive index in the fast axis direction y is Ny, and the refractive index in the thickness direction z is Nz, the following general formula ( I):
Nx> Ny ≧ Nz (I)
The phase difference body according to claim 1, wherein In the plane of the optically anisotropic layer, when the refractive index in the slow axis direction x is Nx, the refractive index in the fast axis direction y is Ny, and the refractive index in the thickness direction z is Nz, the following general formula ( II):
Nx ≦ Ny <Nz (II)
The phase difference body according to claim 1, wherein In the plane of the optically anisotropic layer, when the refractive index in the slow axis direction x is Nx, the refractive index in the fast axis direction y is Ny, and the refractive index in the thickness direction z is Nz, the following general formula ( III):
Nx≈Ny> Nz (III)
The phase difference body according to claim 1, wherein   The phase difference body as described in any one of Claims 1-4 whose height of the convex structure in the said uneven | corrugated shape is 60 nm or more and 200 nm or less.   The phase difference body according to any one of claims 1 to 5, wherein the light-transmitting substrate provided with the optically anisotropic layer is stretched.   The phase difference body as described in any one of Claims 1-6 used for the surface of a polarizing plate. A method for producing a phase difference body comprising a light-transmitting substrate and an optically anisotropic layer,
Preparing the light-transmitting substrate and an optically anisotropic layer-forming composition comprising fine particles as a blocking inhibitor,
The manufacturing method which comprises providing the said composition for optically anisotropic layer formation to the said optically transparent base material, and forming the optically anisotropic layer which has the uneven | corrugated shaped surface.   The manufacturing method according to claim 8, further comprising stretching the light-transmitting substrate provided with the optically anisotropic layer.