Optical laminate, method for producing liquid crystal cured film, and method for producing optical laminate

Abstract

Provided is an optical laminate having high heat resistance. The optical laminate has a protective film, a polarizing plate, a substrate film, and a liquid crystal cured film in this order, the thickness of the liquid crystal cured film being 2.5 [mu] m or more, and the liquid crystal cured film having an extract liquid chromatography measurement result satisfying formula (A). (S / M) / (ST / MT) < = 6.4... (A) S: the total peak area of each liquid crystal monomer, M: the extraction solution concentration, ST: the peak area of toluene, and MT: the toluene solution concentration.

Description

Technical Field

[0001] The present invention relates to an optical laminate, a method for manufacturing a liquid crystal cured film, and a method for manufacturing an optical laminate. Background Art

[0002] A circularly polarizing plate is an optical member formed by laminating a polarizing plate and a retardation plate. For example, in a device that displays an image in a planar state, such as an organic EL image display device, it is used to prevent light reflection at the electrodes constituting the device. As the retardation plate constituting the circularly polarizing plate, a retardation plate using a liquid crystal cured film produced by coating a polymerizable liquid crystal compound on a substrate and curing it is known (see Patent Document 1).

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2022-44293 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] In an optical laminate such as a circularly polarizing plate, high heat resistance is required for the liquid crystal cured film. If the heat resistance of the liquid crystal cured film is low, problems such as a change in the in-plane retardation of the liquid crystal cured film due to heat and an increase in reflectance will occur.

[0008] Therefore, an object of the present invention is to provide an optical laminate having high heat resistance and a method for manufacturing the same. Another object of the present invention is to provide a method for manufacturing a liquid crystal cured film capable of obtaining a liquid crystal cured film having high heat resistance.

[0009] Means for Solving the Problems

[0010] To solve the above problems, the present invention provides the following optical laminate, method for manufacturing a liquid crystal cured film, and method for manufacturing an optical laminate.

[0011] [1] An optical laminate having a protective film, a polarizing plate, a substrate film, and a liquid crystal cured film in this order, wherein the thickness of the liquid crystal cured film is 2.5 μm or more, and the results of extraction liquid chromatography measurement of the liquid crystal cured film satisfy the following formula (A).

[0012] (S / M) / (S T / M T ) ≤ 6.4 … (A)

[0013] S: The sum of the peak areas of each liquid crystal monomer

[0014] M: Extraction solution concentration

[0015] S T: Peak area of toluene

[0016] M T : Concentration of toluene solution

[0017] [2] According to the optical laminate described in [1] above, wherein the transmittance of the protective film at 380 nm is 10% or less.

[0018] [3] According to the optical laminate described in [1] or [2] above, wherein the transmittance of the base film at 380 nm is 50% or more.

[0019] [4] According to the optical laminate described in any one of [1] to [3] above, wherein the moisture permeability of the base film is 50 g / m 2 ·24 hr or more.

[0020] [5] According to the optical laminate described in any one of [1] to [4] above, wherein the thickness of the base film is 30 μm or more.

[0021] [6] According to the optical laminate described in any one of [1] to [5] above, wherein the visible light corrected monomer transmittance Ty of the polarizer is 40% or more.

[0022] [7] According to the optical laminate described in any one of [1] to [6] above, wherein the total thickness of the optical laminate is 150 μm or less, and the thickness of the polarizer is 15 μm or less.

[0023] [8] According to the optical laminate described in any one of [1] to [7] above, wherein the thickness of the liquid crystal cured film is 3.5 μm or less.

[0024] [9] A method for manufacturing a liquid crystal cured film, comprising:

[0025] A step of forming a coating film on a base film using a polymerizable liquid crystal composition containing a polymerizable liquid crystal compound; and

[0026] A step of irradiating active energy rays from both sides of the coating film to cure the coating film, thereby forming a liquid crystal cured film having a thickness of 2.5 μm or more and the extraction liquid chromatography measurement result satisfying the following formula (A).

[0027] (S / M) / (S T / M T ) ≤ 6.4 … (A)

[0028] S: Total of peak areas of each liquid crystal monomer

[0029] M: Concentration of extraction solution

[0030] S T: Peak area of toluene

[0031] M T : Concentration of toluene solution

[0032]

[10] According to the method for manufacturing a liquid crystal cured film described in [9] above, wherein the transmittance of the base film at 380 nm is 50% or more.

[0033]

[11] According to the method for manufacturing a liquid crystal cured film described in [9] or

[10] above, wherein the moisture permeability of the base film is 50 g / m 2 ·24 hr or more.

[0034]

[12] According to the method for manufacturing a liquid crystal cured film described in any one of [9] to

[11] above, wherein the thickness of the base film is 30 μm or more.

[0035]

[13] According to the method for manufacturing a liquid crystal cured film described in any one of [9] to

[12] above, wherein the thickness of the liquid crystal cured film is 3.5 μm or less.

[0036]

[14] A method for manufacturing an optical laminate, which is a method for manufacturing an optical laminate having a protective film, a polarizer, a base film, and a liquid crystal cured film in this order, and the manufacturing method includes a step of manufacturing the liquid crystal cured film by the method for manufacturing a liquid crystal cured film described in any one of [9] to

[13] above.

[0037]

[15] According to the method for manufacturing an optical laminate described in

[14] above, wherein the transmittance of the protective film at 380 nm is 10% or less.

[0038]

[16] According to the method for manufacturing an optical laminate described in

[14] or

[15] above, wherein the visible light corrected monomer transmittance Ty of the polarizer is 40% or more.

[0039]

[17] According to the method for manufacturing an optical laminate described in any one of

[14] to

[16] above, wherein the total thickness of the optical laminate is 150 μm or less, and the thickness of the polarizer is 15 μm or less.

[0040] Advantages of the Invention

[0041] According to the present invention, it is possible to provide an optical laminate having high heat resistance and a method for manufacturing the same. Further, according to the present invention, it is possible to provide a method for manufacturing a liquid crystal cured film that can obtain a liquid crystal cured film having high heat resistance. Description of the Drawings

[0042] Figure 1 It is a schematic cross-sectional view showing an example of the optical laminate of the present invention. Detailed Embodiment

[0043] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings as appropriate. It should be noted that in the drawings, the same or equivalent parts are denoted by the same reference numerals, and redundant descriptions are omitted. In addition, the dimensional ratios of the drawings are not limited to the ratios shown in the figures.

[0044] [Optical laminate]

[0045] The optical laminate of the present invention sequentially includes a protective film, a polarizing plate, a substrate film, and a liquid crystal cured film. The thickness of the liquid crystal cured film is 2.5 μm or more, and the results of extraction liquid chromatography measurement of the liquid crystal cured film satisfy the following formula (A).

[0046] (S / M) / (S T / M T )≤6.4 …(A)

[0047] S: The sum of the peak areas of each liquid crystal monomer

[0048] M: Extraction solution concentration

[0049] S T : The peak area of toluene

[0050] M T : Toluene solution concentration

[0051] According to the above optical laminate, by making the thickness of the liquid crystal cured film 2.5 μm or more and making the value of (S / M) / (S T / M T )6.4 or less, high heat resistance can be achieved. The reason for exerting the above effect is not necessarily clear, but the inventors presume that if the value of (S / M) / (S T / M T )is small, the amount of residual liquid crystal monomers is small. Therefore, even in an environment where heat is applied, the residual monomers are less likely to transfer to other layers such as the adhesive layer. As a result, the heat resistance is improved. In addition, according to the above optical laminate, high flex resistance can be achieved, and the generation of interference unevenness can be suppressed.

[0052] In Figure 1 shows a schematic cross-sectional view of the optical laminate of an embodiment of the present invention. Figure 1The optical laminate 100 shown has, in order, an adhesive layer 1, a liquid crystal cured film 2, an alignment film 3, a substrate film 4, an adhesive layer 5, a polarizing plate 6, an adhesive layer 7, and a protective film 8. In the optical laminate 100, a retardation film 10 is formed by the liquid crystal cured film 2, the alignment film 3, and the substrate film 4. The optical laminate 100 of the present embodiment including the retardation film 10 and the polarizing plate 6 may also be a circularly polarizing plate. Further, a separator may be provided on the surface of the adhesive layer 1 opposite to the liquid crystal cured film 2. Hereinafter, each layer constituting the optical laminate 100 will be described.

[0053] <Adhesive layer 1>

[0054] The adhesive layer is suitable for use when laminating the optical laminate to other adherends. The adhesive layer may be a pressure-sensitive adhesive layer or an adhesive layer.

[0055] As the adhesive composition for forming the adhesive layer, a conventionally well-known adhesive composition having excellent optical transparency can be used without particular limitation. For example, an adhesive composition having a base polymer such as a (meth)acrylic resin, a urethane resin, a silicone resin, or a polyvinyl ether resin can be used. Further, the adhesive composition may be an active energy ray-curable adhesive composition, a thermosetting adhesive composition, or the like. Among them, an adhesive composition having a (meth)acrylic resin as a base polymer with excellent transparency, adhesiveness, re-peelability, weather resistance, heat resistance, etc. is suitable. The adhesive composition may further contain a crosslinking agent, a silane compound, an antistatic agent, and the like.

[0056] ((Meth)acrylic resin)

[0057] The (meth)acrylic resin contained in the adhesive composition is preferably a polymer (hereinafter, also referred to as a “(meth)acrylate polymer”) having a structural unit derived from a (meth)acrylic acid alkyl ester represented by the following formula (I) (hereinafter, also referred to as “structural unit (I)”) as a main component (for example, 50 parts by mass or more per 100 parts by mass of the structural units of the (meth)acrylic resin). It should be noted that in the present specification, the (meth)acrylic resin means either an acrylic resin or a methacrylic resin, and “(meth)” such as (meth)acrylate has the same meaning.

[0058]

Chemical formula 1

[0059]

[0060] [In the formula, R 10 represents a hydrogen atom or a methyl group, R 20represents an alkyl group having 1 to 20 carbon atoms, and the above alkyl group may have any of a linear, branched or cyclic structure, and the hydrogen atoms of the above alkyl group may be substituted with an alkoxy group having 1 to 10 carbon atoms.

[0061] Examples of the (meth)acrylate represented by the formula (I) include: methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, isohexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-dodecyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, stearyl (meth)acrylate, tert-butyl (meth)acrylate, etc. Specific examples of the alkyl acrylate containing an alkoxy group include 2-methoxyethyl (meth)acrylate, ethoxymethyl (meth)acrylate, etc. Among them, n-butyl (meth)acrylate or 2-ethylhexyl (meth)acrylate is preferably included, and n-butyl (meth)acrylate is particularly preferably included.

[0062] The (meth)acrylate polymer may contain structural units derived from other monomers in addition to the structural unit (I). The structural units derived from other monomers may be one kind or two or more kinds. Examples of other monomers that the (meth)acrylate polymer may contain include monomers having a polar functional group, monomers having an aromatic group, and acrylamide-based monomers.

[0063] Examples of the monomer having a polar functional group include (meth)acrylates having a polar functional group. Examples of the polar functional group include: hydroxyl group; carboxyl group; substituted amino group or unsubstituted amino group substituted with an alkyl group having 1 to 6 carbon atoms; heterocyclic groups such as epoxy group.

[0064] Based on 100 parts by mass of all the structural units of the (meth)acrylate polymer, the content of the structural units derived from the monomer having a polar functional group in the (meth)acrylate polymer is preferably 10 parts by mass or less, more preferably 0.5 parts by mass or more and 10 parts by mass or less, further preferably 0.5 parts by mass or more and 5 parts by mass or less, and particularly preferably 1 part by mass or more and 5 parts by mass or less.

[0065] Examples of the monomer having an aromatic group include (meth)acrylate esters having one (meth)acryloyl group and one or more aromatic rings (e.g., benzene ring, naphthalene ring, etc.) in the molecule and having a phenyl group, a phenoxyethyl group, or a benzyl group. By including these structural units, it is possible to suppress the whitening phenomenon of the polarizing plate generated in a high-temperature and high-humidity environment.

[0066] Relative to 100 parts by mass of all the structural units of the (meth)acrylate polymer, the content of the structural units derived from the monomer having an aromatic group in the (meth)acrylate polymer is preferably 20 parts by mass or less, more preferably 4 parts by mass or more and 20 parts by mass or less, and still more preferably 4 parts by mass or more and 15 parts by mass or less.

[0067] Examples of the acrylamide-based monomer include N-(methoxymethyl)acrylamide, N-(ethoxymethyl)acrylamide, N-(propoxymethyl)acrylamide, N-(butoxymethyl)acrylamide, N-(2-methylpropoxymethyl)acrylamide, and the like. By including these structural units, it is possible to suppress the bleeding of additives such as the antistatic agent described later.

[0068] In addition, as the structural units derived from other monomers other than the structural unit (I), it is also possible to include structural units derived from styrene-based monomers, structural units derived from vinyl-based monomers, structural units derived from monomers having a plurality of (meth)acryloyl groups in the molecule, and the like.

[0069] The weight average molecular weight of the (meth)acrylic resin (1) (hereinafter, also simply referred to as "Mw") is preferably 500,000 to 2,500,000. If the weight average molecular weight is 500,000 or more, the durability of the adhesive layer in a high-temperature and high-humidity environment can be improved. If the weight average molecular weight is 2,500,000 or less, the operability when coating the coating liquid containing the adhesive composition becomes good. The molecular weight distribution (Mw / Mn) represented by the ratio of the weight average molecular weight (Mw) to the number average molecular weight (hereinafter, also simply referred to as "Mn") is usually 2 to 10. In this specification, the "weight average molecular weight" and the "number average molecular weight" are polystyrene conversion values measured by gel permeation chromatography (GPC) method.

[0070] When the (meth)acrylic resin is dissolved in ethyl acetate to form a solution with a concentration of 20% by mass, the viscosity at 25 °C is preferably 20 Pa·s or less, more preferably 0.1 to 15 Pa·s. If the viscosity of the (meth)acrylic resin at 25 °C is within the above range, it contributes to the improvement of the durability and reprocessability of the polarizing plate including the adhesive layer formed by the above resin. The above viscosity can be measured by a Brookfield viscometer.

[0071] The glass transition temperature (Tg) of the (meth)acrylic resin is, for example, -60 to 20°C, preferably -50 to 15°C, more preferably -45 to 10°C, and further preferably -40 to 0°C. It should be noted that the glass transition temperature can be measured using a differential scanning calorimeter (DSC).

[0072] The (meth)acrylic resin may contain two or more (meth)acrylate polymers. Examples of such (meth)acrylate polymers include: (meth)acrylate polymers with a relatively low molecular weight, having the structural unit (I) derived from the above (meth)acrylate as the main component and a weight average molecular weight in the range of 50,000 to 300,000.

[0073] The (meth)acrylic resin can generally be produced by known polymerization methods such as solution polymerization, bulk polymerization, suspension polymerization, emulsion polymerization, etc. In the production of the (meth)acrylic resin, polymerization is usually carried out in the presence of a polymerization initiator. The amount of the polymerization initiator used is generally 0.001 to 5 parts by mass relative to 100 parts by mass in total of all the monomers constituting the (meth)acrylic resin. The (meth)acrylic resin can also be produced by a method of polymerization using active energy rays such as ultraviolet rays.

[0074] (Crosslinking agent)

[0075] The adhesive composition preferably contains a crosslinking agent. Examples of the crosslinking agent include conventional crosslinking agents (for example, isocyanate compounds, epoxy compounds, aziridine compounds, metal chelate compounds, peroxides, etc.). In particular, from the viewpoints of the pot life of the adhesive composition, crosslinking speed, and durability of the polarizing plate, isocyanate-based compounds are preferred.

[0076] An isocyanate compound is a compound having at least two isocyanate groups (-NCO) in the molecule. Specifically, examples include: toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, naphthalene diisocyanate, triphenylmethane triisocyanate, etc. In addition, examples also include: adducts obtained by reacting these isocyanate compounds with polyols such as glycerol and trimethylolpropane, dimers, and trimers of these isocyanate compounds. Two or more isocyanate compounds can be combined.

[0077] The proportion of the crosslinking agent is, for example, 0.01 to 10 parts by mass, preferably 0.05 to 5 parts by mass, and further preferably 0.1 to 1 part by mass relative to 100 parts by mass of the (meth)acrylic resin.

[0078] (Silane compound)

[0079] The adhesive composition may further contain a silane compound.

[0080] Examples of the silane compound include: vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylethyldimethylsilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, etc. In addition, the silane compound may contain an oligomer derived from the above silane compound.

[0081] With respect to 100 parts by mass of the (meth)acrylic resin, the content of the silane compound in the adhesive composition is usually 0.01 to 10 parts by mass, preferably 0.05 to 5 parts by mass. If the content of the silane compound is 0.01 part by mass or more, there is a tendency for the adhesion between the adhesive layer and the adherend to be improved. If the content is 10 parts by mass or less, there is a tendency for the exudation of the silane compound from the adhesive layer to be suppressed.

[0082] (Antistatic agent)

[0083] The adhesive composition may further contain an antistatic agent. Examples of the antistatic agent include known antistatic agents, and ionic antistatic agents are suitable. Examples of the cationic component constituting the ionic antistatic agent include organic cations and inorganic cations. Examples of the organic cation include pyridinium cation, imidazolium cation, ammonium cation, sulfonium cation, phosphonium cation, etc. Examples of the inorganic cation include alkali metal cations such as lithium cation, potassium cation, sodium cation, cesium cation, and alkaline earth metal cations such as magnesium cation, calcium cation, etc. As the anionic component constituting the ionic antistatic agent, it may be either an inorganic anion or an organic anion. From the aspect of excellent antistatic performance, an anionic component containing a fluorine atom is preferably included. Examples of the anionic component containing a fluorine atom include: hexafluorophosphate anion (PF6 - ), bis(trifluoromethanesulfonyl)imide anion [(CF3SO2)2N - , bis(fluorosulfonyl)imide anion [(FSO2)2N - anion, etc. From the aspect of excellent temporal stability of the antistatic performance of the adhesive composition, an ionic antistatic agent that is solid at room temperature is preferably used.

[0084] The content of the antistatic agent is, for example, 0.01 to 20 parts by mass, preferably 0.1 to 10 parts by mass, and more preferably 1 to 7 parts by mass with respect to 100 parts by mass of the (meth)acrylic resin.

[0085] The adhesive composition may contain additives such as an ultraviolet absorber, a solvent, a crosslinking catalyst, a tackifying resin (tackifier), a plasticizer, etc. alone or in two or more kinds. In addition, a method of incorporating an ultraviolet curable compound into the adhesive composition, irradiating ultraviolet rays after forming the adhesive layer to cure it, and making the adhesive layer harder is also useful.

[0086] The adhesive layer can be formed, for example, by dissolving or dispersing the above adhesive composition in a solvent to form a solvent-containing adhesive composition, and then coating the surface of the layer on which the adhesive layer is to be provided and drying it.

[0087] The thickness of the adhesive layer is usually 0.1 to 30 μm, preferably 3 to 30 μm, and more preferably 5 to 25 μm.

[0088] <Liquid crystal cured film 2>

[0089] The liquid crystal cured film is a layer that exhibits a phase difference and is an optically anisotropic layer formed of a polymer in which a polymerizable liquid crystal compound is oriented. The liquid crystal cured film is also called a retardation film.

[0090] Regarding the liquid crystal cured film, from the viewpoints of thinning and being able to arbitrarily design the wavelength dispersion characteristics, it is preferable to coat a composition containing a polymerizable liquid crystal compound (hereinafter, also referred to as "polymerizable liquid crystal composition") on a transparent substrate to form a liquid crystal cured film formed of a polymer in which a polymerizable liquid crystal compound is oriented. In addition, the polymerizable liquid crystal composition may further contain a solvent, a photoinitiator, a photosensitizer, a polymerization inhibitor, a leveling agent, an adhesion improver, etc.

[0091] The liquid crystal cured film is usually formed by coating a polymerizable liquid crystal composition on an alignment film formed on a substrate film described later and polymerizing the polymerizable liquid crystal compound contained in the above polymerizable liquid crystal composition. It should be noted that the liquid crystal cured film can also be formed by directly coating a polymerizable liquid crystal composition on the substrate film described later and polymerizing the polymerizable liquid crystal compound contained in the above polymerizable liquid crystal composition. The liquid crystal cured film is usually a film formed by curing a polymerizable liquid crystal compound in an oriented state. In order to generate a phase difference in the viewing plane, it needs to be a cured film formed by polymerizing the polymerizable group in a state where the polymerizable liquid crystal compound is oriented horizontally with respect to the substrate surface. At this time, when the polymerizable liquid crystal compound is a rod-shaped liquid crystal, a positive A plate is sufficient, and when the polymerizable liquid crystal compound is a disc-shaped liquid crystal, a negative A plate is sufficient.

[0092] In the optical laminate in which the substrate film described later functions as a protective film for a polarizing plate, since there is no adhesive layer between the protective film (substrate film) and the liquid crystal cured film, the flexibility is poorer than that of an optical laminate that usually has an adhesive layer serving as a cushioning material between the protective film (substrate film) and the liquid crystal cured film. However, according to the present invention, the flexibility can be improved.

[0093] In order to highly achieve the antireflection function, it is sufficient for the liquid crystal cured film to have a λ / 4 plate function (i.e., a phase difference function of π / 2) in the entire visible light region. Specifically, it may be an inverse wavelength dispersion λ / 4 layer, or two or more kinds of liquid crystal cured films with different orientations may be combined. For example, a liquid crystal cured film having a λ / 2 plate function (i.e., a phase difference function of π) and a liquid crystal cured film having a λ / 4 plate function (i.e., a phase difference function of π / 2) may be combined.

[0094] In addition, from the viewpoint of being able to compensate for the antireflection function in the tilt direction, a layer having anisotropy in the thickness direction (positive C plate) may be included. In addition, each liquid crystal cured film may be tilted and oriented, or a cholesteric orientation state may be formed.

[0095] Regarding the λ / 4 function in the entire visible light region, if the in-plane phase difference of light with respect to a wavelength of λ nm is set as R(λ), the liquid crystal cured film preferably satisfies the optical characteristics shown in the following formula (a), and preferably satisfies the optical characteristics shown in the following formula (a), the following formula (b), and the following formula (c).

[0096] 100 nm < Re(550) < 160 nm …(a)

[0097] (In the formula, Re(550) represents the in-plane phase difference value (in-plane retardation) of light with respect to a wavelength of 550 nm.)

[0098] Re(450) / Re(550) ≤ 1.0 …(b)

[0099] 1.00 ≤ Re(650) / Re(550) …(c)

[0100] (In the formula, Re(450) represents the in-plane phase difference value of light with respect to a wavelength of 450 nm, Re(550) represents the in-plane phase difference value of light with respect to a wavelength of 550 nm, and Re(650) represents the in-plane phase difference value of light with respect to a wavelength of 650 nm.)

[0101] If "Re(450) / Re(550)" of the liquid crystal cured film exceeds 1.0, light leakage on the short wavelength side in the circular polarizing plate having the liquid crystal cured film increases. "Re(450) / Re(550)" is preferably 0.7 or more and 1.0 or less, more preferably 0.80 or more and 0.95 or less, still more preferably 0.80 or more and 0.92 or less, and particularly preferably 0.82 or more and 0.88 or less. The value of "Re(450) / Re(550)" can be arbitrarily adjusted by adjusting the mixing ratio of the polymerizable liquid crystal compound, the stacking angle of the plurality of liquid crystal cured films, and the phase difference.

[0102] The in-plane phase difference of the liquid crystal cured film can be adjusted by the thickness of the liquid crystal cured film. Since the in-plane phase difference is determined by the following formula (d), in order to obtain a desired in-plane phase difference (Re(λ)), it is only necessary to adjust Δn(λ) and the film thickness d. It should be noted that Δn(λ) depends on the molecular structure of the polymerizable liquid crystal compound described later.

[0103] Re(λ) = d × Δn(λ) …(d)

[0104] (In the formula, Re(λ) represents the in-plane phase difference at a wavelength of λ nm, d represents the film thickness, and Δn(λ) represents the birefringence at a wavelength of λ nm.)

[0105] The thickness of the liquid crystal cured film is 2.5 μm or more, preferably more than 2.5 μm, more preferably 2.6 μm or more, still more preferably 2.7 μm or more, and particularly preferably more than 3.0 μm. By making the thickness of the liquid crystal cured film 2.5 μm or more, the heat resistance of the optical laminate can be improved, and in addition, the generation of interference unevenness can be suppressed. In addition, the thickness of the liquid crystal cured film is preferably 5.0 μm or less, more preferably 4.0 μm or less, still more preferably 3.8 μm or less, and particularly preferably 3.5 μm or less. By making the thickness of the liquid crystal cured film 5.0 μm or less, it is easy to sufficiently cure the liquid crystal cured film, and the heat resistance can be further improved. From the above viewpoints, the thickness of the liquid crystal cured film is preferably 2.5 to 5.0 μm, more preferably more than 2.5 μm and 4.0 μm or less, still more preferably 2.6 to 3.8 μm, particularly preferably 2.7 to 3.5 μm, and extremely preferably more than 3.0 μm and 3.5 μm or less. The thickness of the liquid crystal cured film can be measured using an interference film thickness meter, a laser microscope, or a stylus type film thickness meter.

[0106] In the extraction liquid chromatography measurement of the liquid crystal cured film, when the total peak area of each liquid crystal monomer is set to S, the extraction solution concentration is set to M (mg / mL), the peak area of toluene is set to S T , and the toluene solution concentration is set to M T (mg / mL), (S / M) / (ST / M T The value of (S / M) / (S T / M T ) is preferably 6.4 or less, more preferably 5.9 or less, and further preferably 5.1 or less. By making the value of (S / M) / (S

[0107] The liquid crystal cured film is cryogenically pulverized, and 100 mg of the cryogenically pulverized liquid crystal cured film is dissolved in 5 mL of THF. Ultrasonic treatment is performed for 10 minutes, and the extract solution with M = 20 mg / mL is prepared by filtering through a 0.45 μm filter, and S is measured under the following measurement conditions. It should be noted that as the measurement sample, a liquid crystal cured film that has been irradiated with active energy rays and cured for 24 hours or more can be used. In addition, the measurement sample does not need to be a single film of the liquid crystal cured film, and even a substrate film or a liquid crystal cured film with a polarizing plate can be measured in the same way by converting according to the thickness.

[0108] Measuring device: Liquid chromatograph (manufactured by Shimadzu Corporation, trade name: LC-20A)

[0109] Ultraviolet-visible light detector: Photodiode array detector (SPD-40M) manufactured by Shimadzu Corporation

[0110] Column: L-column ODS (3.0 mmφ × 100 mm, 5 μm)

[0111] Mobile phase A: Ultra-pure water (added with 0.1% trifluoroacetic acid)

[0112] Mobile phase B: Acetonitrile (added with 0.1% trifluoroacetic acid)

[0113] Gradient conditions:

[0114] Mobile phase B) 70% - 100% - 100% (0 min. - 15 min. - 45 min.)

[0115] Flow rate: 0.5 mL / min.

[0116] Oven temperature: 40°C

[0117] UV detection wavelength: 280 nm (bandwidth: 4 nm, slit width: 8 nm)

[0118] Injection volume: 5 μL

[0119] (Polymerizable liquid crystal compound)

[0120] The polymerizable liquid crystal compounds contained in the polymerizable liquid crystal composition refer to liquid crystal compounds having polymerizable groups, particularly photopolymerizable groups. As such polymerizable liquid crystal compounds, conventionally known polymerizable liquid crystal compounds can be used. The photopolymerizable group refers to a group that can participate in a polymerization reaction through reactive species generated by a photopolymerization initiator, such as reactive free radicals, acids, etc. Examples of the photopolymerizable group include vinyl, vinyloxy, 1-chloroethenyl, isopropenyl, 4-vinylphenyl, acryloyloxy, methacryloyloxy, epoxyethyl, oxetanyl, etc. Among them, acryloyloxy, methacryloyloxy, vinyloxy, epoxyethyl, and oxetanyl are preferred, and acryloyloxy is more preferred. The liquid crystallinity can be thermotropic liquid crystal or lyotropic liquid crystal. From the aspect of enabling precise film thickness control, thermotropic liquid crystal is preferred. In addition, as the phase ordered structure in thermotropic liquid crystal, it can be nematic liquid crystal or smectic liquid crystal. In addition, it can be rod-shaped liquid crystal or disc-shaped liquid crystal. The polymerizable liquid crystal compounds can be used alone or in combination of two or more.

[0121] As the polymerizable liquid crystal compound, from the viewpoint of exhibiting inverse wavelength dispersion, a liquid crystal having a mesomorphic structure in a T-shaped or H-shaped form that further has birefringence in a direction perpendicular to the molecular long axis direction is preferred. From the viewpoint of obtaining stronger dispersion, a T-shaped liquid crystal is more preferred. As the structure of the T-shaped liquid crystal, specifically, for example, the compound represented by the following formula (II) can be cited.

[0122]

Chemical formula 2

[0123]

[0124] In formula (II), Ar represents a divalent aromatic group which may have substituents. The divalent aromatic group preferably contains at least one of a nitrogen atom, an oxygen atom, and a sulfur atom. When there are two or more aromatic groups contained in the divalent group Ar, the two or more aromatic groups may be bonded to each other through a divalent bonding group such as a single bond, -CO-O-, -O-.

[0125] G 1 and G 2 each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group. Here, the hydrogen atoms contained in the divalent aromatic group or the divalent alicyclic hydrocarbon group may be substituted with a halogen atom, an alkyl group having 1 to 4 carbon atoms, a fluoroalkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group, or a nitro group, and the carbon atoms constituting the divalent aromatic group or the divalent alicyclic hydrocarbon group may be replaced with an oxygen atom, a sulfur atom, or a nitrogen atom.

[0126] L 1 、L 2 、B1 and B 2 Each independently represents a single bond or a divalent linking group.

[0127] k and l each independently represent an integer from 0 to 3 and satisfy the relationship 1 ≤ k + l. Here, when 2 ≤ k + l, B 1 and B 2 , G 1 and G 2 may be the same as or different from each other.

[0128] E 1 and E 2 Each independently represents an alkanediyl group having 1 to 17 carbon atoms. Here, the hydrogen atoms contained in the alkanediyl group may be substituted by halogen atoms, and the -CH2- contained in the alkanediyl group may be replaced by -O-, -S-, -COO-. In the case of having multiple -O-, -S-, -COO-, they are not adjacent to each other. P 1 and P 2 Independently represent a polymerizable group or a hydrogen atom, and at least one is a polymerizable group.

[0129] G 1 and G 2 Each independently is preferably a 1,4-phenylene group that can be substituted by at least one substituent selected from halogen atoms and alkyl groups having 1 to 4 carbon atoms, a 1,4-cyclohexanediyl group that can be substituted by at least one substituent selected from halogen atoms and alkyl groups having 1 to 4 carbon atoms, more preferably a 1,4-phenylene group substituted by a methyl group, an unsubstituted 1,4-phenylene group, or an unsubstituted 1,4-trans-cyclohexanediyl group, and particularly preferably an unsubstituted 1,4-phenylene group or an unsubstituted 1,4-trans-cyclohexanediyl group.

[0130] In addition, it is preferred that at least one of the plurality of G 1 and G 2 is a divalent alicyclic hydrocarbon group. In addition, it is more preferably that at least one of the G 1 or L 2 bonded to L 1 and G 2 is a divalent alicyclic hydrocarbon group.

[0131] L 1 and L 2 Each independently is preferably a single bond, an alkylene group having 1 to 4 carbon atoms, -O-, -S-, -R a1 OR a2 -, -R a3 COOR a4 -, -R a5 OCOR a6 -, R a7 OC=OORa8 -, -N=N-, -CR c =CR d -, or -C≡C-. Here, R a1 ~R a8 each independently represents a single bond, or an alkylene group having 1 to 4 carbon atoms, R c and R d represent an alkyl group having 1 to 4 carbon atoms or a hydrogen atom. L 1 and L 2 each independently is more preferably a single bond, -OR a2-1 -, -CH2-, -CH2CH2-, -COOR a4-1 -, or OCOR a6-1 -. Here, R a2-1 , R a4-1 , R a6-1 each independently represents any one of a single bond, -CH2-, -CH2CH2-. L 1 and L 2 each independently is further preferably a single bond, -O-, -CH2CH2-, -COO-, -COOCH2CH2-, or -OCO-.

[0132] B 1 and B 2 each independently is preferably a single bond, an alkylene group having 1 to 4 carbon atoms, -O-, -S-, -R a9 OR a10 -, -R a11 COOR a12 -, -R a13 OCOR a14 -, or -R a15 OC=OOR a16 -. Here, R a9 ~R a16 each independently represents a single bond, or an alkylene group having 1 to 4 carbon atoms. B 1 and B 2 each independently is more preferably a single bond, -OR a10-1 -, -CH2-, -CH2CH2-, -COOR a12 -1 -, or -OCOR a14-1 -. Here, R a10-1 , R a12-1 , R a14-1 each independently represents any one of a single bond, -CH2-, -CH2CH2-. B 1 and B 2Each is independently further preferably a single bond, -O-, -CH2CH2-, -COO-, -COOCH2CH2-, -OCO-, or -OCOCH2CH2-.

[0133] From the viewpoint of exhibiting inverse wavelength dispersibility, k and l are preferably in the range of 2 ≤ k + l ≤ 6, preferably k + l = 4, more preferably k = 2 and l = 2. If k = 2 and l = 2, a symmetric structure is formed, which is therefore preferred.

[0134] E 1 and E 2 Each is independently preferably an alkanediyl having 1 to 17 carbon atoms, more preferably an alkanediyl having 4 to 12 carbon atoms.

[0135] As the polymerizable group represented by P 1 or P 2 Examples of the polymerizable group include an epoxy group, a vinyl group, a vinyloxy group, a 1-chloroethylene group, an isopropenyl group, a 4-vinylphenyl group, an acryloyloxy group, a methacryloyloxy group, an epoxyethyl group, and an oxetanyl group. Among them, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an epoxyethyl group, and an oxetanyl group are preferred, and an acryloyloxy group is more preferred.

[0136] Ar preferably has at least one selected from an aromatic hydrocarbon ring which may have a substituent, an aromatic heterocyclic ring which may have a substituent, and an electron-withdrawing group. Examples of the aromatic hydrocarbon ring include a benzene ring, a naphthalene ring, an anthracene ring, etc., and a benzene ring and a naphthalene ring are preferred. Examples of the aromatic heterocyclic ring include a furan ring, a benzofuran ring, a pyrrole ring, an indole ring, a thiophene ring, a benzothiophene ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a triazole ring, a triazine ring, a pyrroline ring, an imidazole ring, a pyrazole ring, a thiazole ring, a benzothiazole ring, a thiophenothiazole ring, an oxazole ring, a benzoxazole ring, and a phenanthroline ring, etc. Among them, having a thiazole ring, a benzothiazole ring, or a benzofuran ring is preferred, and having a benzothiazolyl group is further preferred. In addition, when Ar contains a nitrogen atom, the nitrogen atom preferably has π electrons.

[0137] In formula (II), the total number N of π electrons contained in the divalent aromatic group represented by Ar π is preferably 8 or more, more preferably 10 or more, further preferably 14 or more, and particularly preferably 16 or more. In addition, it is preferably 30 or less, more preferably 26 or less, and further preferably 24 or less.

[0138] Examples of the aromatic group represented by Ar include the following groups.

[0139] [[Chemical formula 3]]

[0140]

[0141] In formulas (Ar-1) to (Ar-23), the * mark represents a connecting part, and Z 0 、Z 1 and Z 2 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, a cyano group, a nitro group, an alkylsulfinyl group having 1 to 12 carbon atoms, an alkylsulfonyl group having 1 to 12 carbon atoms, a carboxyl group, a fluoroalkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkylthio group having 1 to 12 carbon atoms, an N-alkylamino group having 1 to 12 carbon atoms, an N,N-dialkylamino group having 2 to 12 carbon atoms, an N-alkylsulfamoyl group having 1 to 12 carbon atoms, or an N,N-dialkylsulfamoyl group having 2 to 12 carbon atoms.

[0142] Q 1 、Q 2 and Q 3 each independently represents -CR 2’ R 3’ -, -S-, -NH-, -NR 2’ -, -CO-, or -O-, and R 2’ and R 3’ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

[0143] J 1 and J 2 each independently represents a carbon atom or a nitrogen atom.

[0144] Y 1 、Y 2 and Y 3 each independently represents an optionally substituted aromatic hydrocarbon group or an aromatic heterocyclic group.

[0145] W 1 and W 2 each independently represents a hydrogen atom, a cyano group, a methyl group, or a halogen atom, and m represents an integer of 0 to 6.

[0146] As the aromatic hydrocarbon group for Y 1 、Y 2 and Y 3 Examples of the aromatic hydrocarbon group include aromatic hydrocarbon groups having 6 to 20 carbon atoms such as phenyl, naphthyl, anthryl, phenanthryl, and biphenyl, preferably phenyl and naphthyl, and more preferably phenyl. Examples of the aromatic heterocyclic group include aromatic heterocyclic groups having 4 to 20 carbon atoms containing at least one heteroatom such as nitrogen, oxygen, and sulfur, such as furyl, pyrrolyl, thienyl, pyridyl, thiazolyl, and benzothiazolyl, preferably furyl, thienyl, pyridyl, thiazolyl, and benzothiazolyl.

[0147] Y 1 、Y 2 and Y 3Each independently may be a polycyclic aromatic hydrocarbon group or a polycyclic aromatic heterocyclic group which may be substituted. The polycyclic aromatic hydrocarbon group refers to a condensed polycyclic aromatic hydrocarbon group or a group derived from a collection of aromatic rings. The polycyclic aromatic heterocyclic group refers to a condensed polycyclic aromatic heterocyclic group or a group derived from a collection of aromatic rings.

[0148] Z 0 , Z 1 and Z 2 Each of Z is independently preferably a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, a cyano group, a nitro group, or an alkoxy group having 1 to 12 carbon atoms. 0 More preferably, a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or a cyano group. 1 and Z 2 More preferred are a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group and a cyano group.

[0149] Q 1 , Q 2 and Q 3 Preferred are -NH-, -S-, -NR 2’ -、-O-,R 2’ A hydrogen atom is preferred, and -S-, -O-, and -NH- are particularly preferred.

[0150] Among the formulae (Ar-1) to (Ar-23), the formulae (Ar-6) and (Ar-7) are preferred from the viewpoint of molecular stability.

[0151] In formula (Ar-16) ~ (Ar-23), Y 1 The nitrogen atom and Z 0 Together, they form an aromatic heterocyclic group. Examples of the aromatic heterocyclic group include the aromatic heterocyclic groups described above as aromatic heterocyclic rings that Ar may have, such as a pyrrole ring, an imidazole ring, a pyrroline ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, an indole ring, a quinoline ring, an isoquinoline ring, a purine ring, and a pyrrolidine ring. The aromatic heterocyclic group may have a substituent. In addition, Y 1 The nitrogen atom and Z 0 Together, they are the above-mentioned optionally substituted polycyclic aromatic hydrocarbon groups or polycyclic aromatic heterocyclic groups, for example, benzofuran ring, benzothiazole ring, benzoxazole ring, etc.

[0152] Among the polymerizable liquid crystal compounds, compounds having a maximum absorption wavelength of 300 to 400 nm are preferred. When a photopolymerization initiator is included in the polymerizable liquid crystal composition, there is a possibility that the polymerization reaction and gelation of the polymerizable liquid crystal compound occur during long-term storage. However, if the maximum absorption wavelength of the polymerizable liquid crystal compound is 300 to 400 nm, even when exposed to ultraviolet light during storage, the generation of reactive species from the photopolymerization initiator and the polymerization reaction and gelation of the polymerizable liquid crystal compound caused by the reactive species can be effectively suppressed. Therefore, it is advantageous in terms of the long-term stability of the polymerizable liquid crystal composition, and the orientation and film thickness uniformity of the obtained liquid crystal cured film can be improved. It should be noted that the maximum absorption wavelength of the polymerizable liquid crystal compound can be measured using an ultraviolet-visible spectrophotometer in a solvent. This solvent is a solvent capable of dissolving the polymerizable liquid crystal compound, and examples thereof include chloroform.

[0153] Assuming the total amount of the solid components of the polymerizable liquid crystal composition is 100% by mass, the content of the polymerizable liquid crystal compound in the polymerizable liquid crystal composition is, for example, 70 to 99.5% by mass, preferably 80 to 99% by mass, more preferably 85 to 98% by mass, and still more preferably 90 to 95% by mass. If the content of the polymerizable liquid crystal compound is within the above range, it is advantageous from the viewpoint of the orientation of the obtained liquid crystal cured film. It should be noted that in this specification, the solid components of the polymerizable liquid crystal composition refer to all components after removing volatile components such as organic solvents from the polymerizable liquid crystal composition.

[0154] The polymerizable liquid crystal composition may further contain reactive additives such as a solvent, a leveling agent, a polymerization initiator, a photosensitizer, a polymerization inhibitor, a crosslinking agent, and an adhesive. From the viewpoint of processability, it is preferred to contain a solvent and a leveling agent.

[0155] (Configuration formed by combining a positive wavelength dispersion λ / 2 layer and a positive wavelength dispersion λ / 4 layer)

[0156] As one of the methods for achieving antireflection performance, a configuration formed by combining a positive wavelength dispersion λ / 2 layer and a positive wavelength dispersion λ / 4 layer is known. This configuration can be obtained, for example, by combining a layer having the optical characteristics represented by formulas (e), (g), and (h) with a layer having the optical characteristics represented by formulas (f), (g), and (h) in a specific slow axis relationship.

[0157] 100 nm < Re(550) < 160 nm … (e)

[0158] 200 nm < Re(550) < 320 nm … (f)

[0159] Re(450) / Re(550) ≥ 1.00 … (g)

[0160] 1.00 ≥ Re(650) / Re(550) …(h)

[0161] As a method of combining the above-described configurations, known methods such as Japanese Unexamined Patent Application Publication No. 2015-163935 and WO2013 / 137464 can be cited. From the viewpoint of viewing angle compensation, it is preferable to use a λ / 2 layer of a polymer containing a discotic polymerizable liquid crystal compound and a λ / 4 layer of a polymer containing a rod-like polymerizable liquid crystal compound.

[0162] In addition to the configuration in which the above positive wavelength dispersive λ / 2 layer and positive wavelength dispersive λ / 4 layer are combined, for the configurations of tilted alignment and cholesteric alignment, there is no particular limitation as long as the antireflection function is achieved. For example, known configurations such as WO2021 / 060378, WO2021 / 132616, and WO2021 / 132624 can be cited.

[0163] In the configuration in which the above positive wavelength dispersive λ / 2 layer and positive wavelength dispersive λ / 4 layer are combined, the "thickness of the liquid crystal cured film" in the present invention refers to the total value of the thicknesses of the positive wavelength dispersive λ / 2 layer and the positive wavelength dispersive λ / 4 layer. Among them, when there is an adhesive layer between the positive wavelength dispersive λ / 2 layer and the positive wavelength dispersive λ / 4 layer, the thickness of the adhesive layer is not included in the "thickness of the liquid crystal cured film".

[0164] As the discotic polymerizable liquid crystal compound, for example, a compound containing a group represented by the following formula (W) can be cited.

[0165] [Chemical formula 4]

[0166]

[0167] [In formula (W), R 40 each independently represents the following formula (W-1) to (W-5).]

[0168] [Chemical formula 5]

[0169]

[0170] X 40 and Z 40 represent an alkanediyl group having 1 to 12 carbon atoms, and the hydrogen atoms contained in the alkanediyl group may be substituted with an alkoxy group having 1 to 5 carbon atoms, and the hydrogen atoms contained in the alkoxy group may be substituted with a halogen atom. In addition, -CH2- constituting the alkanediyl group may be replaced with -O- or -CO-.

[0171] (Positive C plate)

[0172] The positive C-plate is not particularly limited as long as it has anisotropy in the thickness direction. In the case where no tilt alignment or cholesteric alignment is performed, it has the optical characteristics represented by the following formula (i).

[0173] nx≈ny<nz …(i)

[0174] The in-plane retardation Re(550) of the positive C-plate at a wavelength of 550 nm is usually in the range of 0 to 10 nm, preferably in the range of 0 to 5 nm. In addition, the retardation Rth(550) in the thickness direction at a wavelength of 550 nm is usually in the range of -170 nm or more and -10 nm or less, preferably -150 nm or more and -20 nm or less, more preferably -100 nm or more and -40 nm or less. If the retardation in the thickness direction is within this range, the antireflection characteristics in the tilt direction can be further improved.

[0175] When the positive C-plate is a stretched film, its thickness is usually 300 μm or less, preferably 5 μm or more and 100 μm or less, more preferably 10 μm or more and 50 μm or less. When the positive C-plate is a coating layer formed by polymerizing a polymerizable liquid crystal, its thickness is usually 10 μm or less, preferably 5 μm or less, more preferably 0.3 μm or more and 3 μm or less. It should be noted that the thickness of the positive C-plate is not included in the "thickness of the liquid crystal cured film" in the present invention.

[0176] The positive C-plate is preferably a coating layer formed by polymerizing one or more polymerizable liquid crystal compounds. As the polymerizable liquid crystal compound, a rod-shaped polymerizable liquid crystal compound is preferably used.

[0177] Examples of the rod-shaped polymerizable liquid crystal compound include compounds represented by formula (III), formula (IV), formula (V), formula (VI), formula (VII), or formula (VIII).

[0178] P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-A14-B16-E12-B17-P12 (III)

[0179] P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-A14-F11 (IV)

[0180] P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-E12-B17-P12 (V)

[0181] P11-B11-E11-B12-A11-B13-A12-B14-A13-F11 (VI)

[0182] P11 - B11 - E11 - B12 - A11 - B13 - A12 - B14 - E12 - B17 - P12 (VII)

[0183] P11 - B11 - E11 - B12 - A11 - B13 - A12 - F11 (VIII)

[0184] [In the formula, A11 represents a divalent alicyclic hydrocarbon group or a divalent aromatic hydrocarbon group. The hydrogen atoms contained in the divalent alicyclic hydrocarbon group and the divalent aromatic hydrocarbon group may be substituted with a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, or a nitro group, and the hydrogen atoms contained in the alkyl group having 1 to 6 carbon atoms and the alkoxy group having 1 to 6 carbon atoms may be substituted with a fluorine atom.]

[0185] B11 represents -O-, -S-, -CO - O-, -O - CO-, -O - CO - O-, -CO - NR 16 -, -NR 16 -, -CO-, -CO-, -CS-, or a single bond. R 16 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.]

[0186] B12 and B13 each independently represent -C≡C-, -CH=CH-, -CH2 - CH2-, -O-, -S-, -C(=O)-, -C(=O)-O-, -O - C(=O)-, -O - C(=O)-O-, -CH=N-, -N=CH-, -N=N-, -C(=O)-NR 16 -, -NR 16 -, -C(=O)-, -OCH2-, -OCF2-, -CH2O-, -CF2O-, -CH=CH - C(=O)-O-, -O - C(=O)-CH=CH-, or a single bond.]

[0187] E11 represents an alkanediyl group having 1 to 12 carbon atoms, and the hydrogen atoms contained in the alkanediyl group may be substituted with an alkoxy group having 1 to 5 carbon atoms, and the hydrogen atoms contained in the alkoxy group may be substituted with a halogen atom. In addition, -CH2 - constituting the alkanediyl group may be replaced with -O- or -CO-.]

[0188] The number of carbon atoms of the aromatic hydrocarbon group and the alicyclic hydrocarbon group of A11 is preferably in the range of 3 to 18, more preferably in the range of 5 to 12, and particularly preferably 5 or 6. As A11, cyclohexane - 1,4 - diyl and 1,4 - phenylene are preferred.]

[0189] As E11, a linear alkanediyl group having 1 to 12 carbon atoms is preferred. -CH2 - constituting the alkanediyl group may be replaced with -O-.]

[0190] As E11, specifically, examples thereof include linear alkanediyls having 1 to 12 carbon atoms such as methylene, ethylene, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, and dodecane-1,12-diyl; -CH2-CH2-O-CH2-CH2-, -CH2-CH2-O-CH2-CH2-O-CH2-CH2-, and -CH2-CH2-O-CH2-CH2-O-CH2-CH2-O-CH2-CH2-.

[0191] As B11, -O-, -S-, -CO-O-, and -O-CO- are preferred, and among them, -CO-O- is more preferred.

[0192] As B12 and B13, -O-, -S-, -C(=O)-, -C(=O)-O-, -O-C(=O)-, and -O-C(=O)-O- are each independently preferred, and among them, -O- or -O-C(=O)-O- is more preferred.

[0193] As the polymerizable group represented by P11, from the viewpoint of high polymerization reactivity, particularly high photopolymerization reactivity, a radical polymerizable group or a cationic polymerizable group is preferred. From the viewpoint of easy handling and easy production of the liquid crystal compound itself, the polymerizable group is preferably a group represented by the following formula (P-11) to formula (P-15).

[0194] [Chemical Formula 6]

[0195]

[0196] [In formula (P-11) to (P-15), R 17 to R 21 each independently represent an alkyl group having 1 to 6 carbon atoms or a hydrogen atom. ]

[0197] Specific examples of the group represented by formula (P-11) to formula (P-15) include groups represented by the following formula (P-16) to formula (P-20).

[0198] [Chemical Formula 7]

[0199]

[0200] P11 is preferably a group represented by formula (P-14) to formula (P-20), and more preferably vinyl, p-stilbenyl, epoxy group, or oxetanyl.

[0201] The group shown in P11-B11- is further preferably acryloyloxy or methacryloyloxy.

[0202] In formulas (III) to (VIII), A12 to A14 are each independently the same as A11 in meaning, B14 to B16 are each independently the same as B12 in meaning, B17 is the same as B11 in meaning, and E12 is the same as E11 in meaning. F11 represents a hydrogen atom, an alkyl group having 1 to 13 carbon atoms, an alkoxy group having 1 to 13 carbon atoms, a cyano group, a nitro group, a trifluoromethyl group, a dimethylamino group, a hydroxyl group, a hydroxymethyl group, a formyl group, a sulfo group (-SO3H), a carboxyl group, an alkoxycarbonyl group having 1 to 10 carbon atoms, or a halogen atom, and -CH2- constituting the alkyl group and the alkoxy group may be replaced by -O-.

[0203] (Solvent)

[0204] The polymerizable liquid crystal composition may contain a solvent. Generally, since the viscosity of the polymerizable liquid crystal compound is high, by forming a polymerizable liquid crystal composition dissolved in a solvent, coating becomes easy. As a result, in most cases, it is easy to form a liquid crystal cured film. As the solvent, a solvent that can completely dissolve the polymerizable liquid crystal compound is preferred, and further, a solvent that is inactive to the polymerization reaction of the polymerizable liquid crystal compound is preferred.

[0205] Examples of the solvent include alcohol solvents such as methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, and propylene glycol monomethyl ether; ester solvents such as ethyl acetate, butyl acetate, ethylene glycol monomethyl ether acetate, γ-butyrolactone, propylene glycol monomethyl ether acetate, and ethyl lactate; ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane, and heptane; aromatic hydrocarbon solvents such as toluene and xylene, nitrile solvents such as acetonitrile; ether solvents such as tetrahydrofuran and dimethoxyethane; chlorine-containing solvents such as chloroform and chlorobenzene; amide solvents such as dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone, and 1,3-dimethyl-2-imidazolidinone. These solvents can be used alone or in combination of two or more.

[0206] Relative to the total amount of the polymerizable liquid crystal composition, the content of the solvent is preferably 50 to 98% by mass. In other words, the content of the solid component in the polymerizable liquid crystal composition is preferably 2 to 50% by mass, more preferably 5 to 30% by mass. If the content of the solid component is 50% by mass or less, the viscosity of the polymerizable liquid crystal composition becomes low, and thus the thickness of the liquid crystal cured film becomes substantially uniform. As a result, there is a tendency that unevenness is less likely to occur in the liquid crystal cured film. In addition, the content of the solid component can be determined in consideration of the thickness of the liquid crystal cured film to be manufactured.

[0207] (Leveling agent)

[0208] The polymerizable liquid crystal composition may contain a leveling agent. A leveling agent is an additive having a function of adjusting the fluidity of the composition and making the film obtained by coating the composition flatter. Examples thereof include organically modified silicone-based, polyacrylate-based, and perfluoroalkyl-based leveling agents. Among them, in the case of making the composition horizontally aligned, polyacrylate-based leveling agents and perfluoroalkyl-based leveling agents are preferred. In the case of making the composition vertically aligned, organically modified silicone-based leveling agents and perfluoroalkyl-based leveling agents are preferred.

[0209] When the polymerizable liquid crystal composition contains a leveling agent, it is preferably 0.01 to 5 parts by mass, more preferably 0.05 to 3 parts by mass, relative to 100 parts by mass of the content of the polymerizable liquid crystal compound. If the content of the leveling agent is within the above range, there is a tendency that the polymerizable liquid crystal compound is easily horizontally aligned and the obtained liquid crystal cured film becomes smoother. If the content of the leveling agent relative to the polymerizable liquid crystal compound exceeds the above range, there is a tendency that unevenness is likely to occur in the obtained liquid crystal cured film. It should be noted that the polymerizable liquid crystal composition may contain two or more kinds of leveling agents.

[0210] (Polymerization initiator)

[0211] The polymerizable liquid crystal composition may contain a polymerization initiator. A polymerization initiator is a compound capable of initiating a polymerization reaction of a polymerizable liquid crystal compound or the like. As the polymerization initiator, from the viewpoint of not depending on the phase state of thermotropic liquid crystals, a photopolymerization initiator that generates active free radicals by the action of light is preferred.

[0212] As long as the photopolymerization initiator is a compound capable of initiating the polymerization reaction of the polymerizable liquid crystal compound, a known photopolymerization initiator can be used. Specifically, photopolymerization initiators capable of generating active free radicals or acids by the action of light can be cited. Among them, photopolymerization initiators that generate free radicals by the action of light are preferred. The photopolymerization initiators can be used alone or in combination of two or more.

[0213] As the photopolymerization initiator, known photopolymerization initiators can be used. For example, as the photopolymerization initiator that generates active free radicals, self-cleavage type benzoin compounds, acetophenone compounds, hydroxyacetophenone compounds, α-aminobenzophenone compounds, oxime ester compounds, acylphosphine oxide compounds, azo compounds, etc. can be used. As the hydrogen abstraction type, benzophenone compounds, alkylbenzophenone compounds, benzoin ether compounds, benzil ketal compounds, dibenzosuberone compounds, anthraquinone compounds, xanthene compounds, thioxanthene compounds, halogenated acetophenone compounds, dialkoxyacetophenone compounds, halogenated bisimidazole compounds, halogenated triazine compounds, triazine compounds, etc. can be used. As the photopolymerization initiator that generates acid, iodonium salts and sulfonium salts, etc. can be used. From the viewpoint of excellent reaction efficiency at low temperatures, self-cleavage type photopolymerization initiators are preferred, and acetophenone compounds, hydroxyacetophenone compounds, α-aminobenzophenone compounds, and oxime ester compounds are particularly preferred.

[0214] The content of the polymerization initiator in the liquid crystal polymerizable composition can be appropriately adjusted according to the type and amount of the liquid crystal polymerizable compound. Usually, it is 0.1 to 30 parts by mass, preferably 0.5 to 10 parts by mass, and more preferably 0.5 to 8 parts by mass with respect to 100 parts by mass of the content of the liquid crystal polymerizable compound. If the content of the polymerization initiator is within the above range, polymerization can be carried out without disturbing the orientation of the liquid crystal polymerizable compound.

[0215] (Sensitizer)

[0216] The liquid crystal polymerizable composition may contain a sensitizer. As the sensitizer, a photosensitizer is preferred. Examples of such a sensitizer include: xanthene compounds such as xanthene and thioxanthene (for example, 2,4-diethylthioxanthene, 2-isopropylthioxanthene, etc.); anthracene compounds such as anthracene and alkoxy-containing anthracene (for example, dibutoxyanthracene, etc.); phenothiazine and rubrene, etc.

[0217] When the liquid crystal polymerizable composition contains a sensitizer, the polymerization reaction of the liquid crystal polymerizable compound contained in the liquid crystal polymerizable composition can be further promoted. The usage amount of the sensitizer is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 10 parts by mass, and further preferably 0.5 to 8 parts by mass with respect to 100 parts by mass of the content of the liquid crystal polymerizable compound.

[0218] (Antioxidant)

[0219] From the viewpoint of enabling the polymerization reaction to proceed stably, the liquid crystal polymerizable composition may contain an antioxidant. By means of the antioxidant, the progress degree of the polymerization reaction of the liquid crystal polymerizable compound can be controlled.

[0220] As the above antioxidant, it may be a main antioxidant selected from phenolic antioxidants, amine antioxidants, quinone antioxidants, and nitroso antioxidants, or it may be a co-antioxidant selected from phosphorus antioxidants and sulfur antioxidants.

[0221] When the polymerizable liquid crystal composition contains an antioxidant, the content of the antioxidant is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 10 parts by mass, and still more preferably 0.5 to 8 parts by mass with respect to 100 parts by mass of the content of the polymerizable liquid crystal compound. The antioxidant can be used alone or in combination of two or more. If the content of the antioxidant is within the above range, polymerization can be carried out without disturbing the orientation of the polymerizable liquid crystal compound.

[0222] (Reactive additive)

[0223] The polymerizable liquid crystal composition may contain a reactive additive. As the reactive additive, it preferably has a carbon-carbon unsaturated bond, an active hydrogen-reactive group, and a mercapto group in its molecule. It should be noted that the "active hydrogen-reactive group" mentioned here refers to a group that is reactive with a group having active hydrogen such as a carboxyl group (-COOH), a hydroxyl group (-OH), and an amino group (-NH2). Representative examples thereof include a glycidyl group, an oxazoline group, a carbodiimide group, an aziridinyl group, an imide group, an isocyanate group, a thiocyanate group, and a maleic anhydride group. The number of reactive groups possessed by the reactive additive is usually 1 to 20, preferably 1 to 10, respectively.

[0224] <Method for manufacturing a liquid crystal cured film>

[0225] The method for manufacturing a liquid crystal cured film according to this embodiment includes: a step of forming a coating film on a substrate film using a polymerizable liquid crystal composition containing a polymerizable liquid crystal compound; and a step of curing the coating film by irradiating active energy rays from both sides of the coating film, thereby forming a liquid crystal cured film having a thickness of 2.5 μm or more and the results of extraction liquid chromatography measurement satisfying the following formula (A).

[0226] (S / M) / (S T / M T ) ≤ 6.4... (A)

[0227] S: The sum of the peak areas of each liquid crystal monomer

[0228] M: Extraction solution concentration

[0229] S T : The peak area of toluene

[0230] M T : Toluene solution concentration

[0231] In the step of forming a coating film, a coating film can be formed by coating a polymerizable liquid crystal composition on an alignment film formed on a substrate film described below and drying it. In the step of forming a liquid crystal cured film, the polymerizable liquid crystal compound in the coating film is polymerized by irradiating active energy rays, whereby a liquid crystal cured film can be formed.

[0232] (Coating of the polymerizable liquid crystal composition)

[0233] Examples of the method of coating the polymerizable liquid crystal composition on the alignment film include an extrusion coating method, a direct gravure coating method, an offset gravure coating method, a CAP coating method, a slit coating method, a microgravure method, a die coating method, an inkjet method, etc. In addition, there are also methods of coating using coating machines such as a dip coater, a bar coater, and a spin coater. Among them, in the case of continuously coating in a roll-to-roll form, a coating method based on the microgravure method, the inkjet method, the slit coating method, or the die coating method is preferred. In the case of coating on a single substrate such as glass, a spin coating method with high uniformity is preferred. In the case of coating in a roll-to-roll form, an alignment film can also be formed by coating an alignment film-forming composition on the substrate film, and then the polymerizable liquid crystal composition can be continuously coated on the obtained alignment film.

[0234] (Drying of the polymerizable liquid crystal composition)

[0235] Examples of the drying method for removing the solvent contained in the polymerizable liquid crystal composition include natural drying, ventilation drying, heat drying, reduced-pressure drying, and combinations thereof. Among them, natural drying or heat drying is preferred. The drying temperature is preferably in the range of 0 to 200°C, more preferably in the range of 20 to 150°C, and further preferably in the range of 50 to 130°C. The drying time is preferably 10 seconds to 10 minutes, more preferably 30 seconds to 5 minutes. Thereby, a coating film containing a polymerizable liquid crystal compound can be formed. The alignment film-forming composition and the alignment polymer composition can also be dried in the same manner.

[0236] (Polymerization of the polymerizable liquid crystal compound)

[0237] As a method for polymerizing a polymerizable liquid crystal compound, photopolymerization is preferred. Photopolymerization is carried out by irradiating a laminate obtained by sequentially laminating a substrate film, an alignment film, and a coating film containing a polymerizable liquid crystal compound with active energy rays. As the active energy rays to be irradiated, they are appropriately selected according to the type of the polymerizable liquid crystal compound contained in the dried film (especially the type of the photopolymerizable functional group possessed by the polymerizable liquid crystal compound), the type of the photopolymerization initiator in the case of containing a photopolymerization initiator, and their amounts. Specifically, one or more types of light selected from visible light, ultraviolet light, infrared light, X-rays, α-rays, β-rays, and γ-rays can be cited. Among them, from the aspect of easily controlling the progress of the polymerization reaction and the aspect that a device widely used in the art can be used as a photopolymerization device, ultraviolet light is preferred, and the type of the polymerizable liquid crystal compound is preferably selected so that photopolymerization can be carried out using ultraviolet light.

[0238] As a light source for the above-mentioned active energy rays, for example, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a halogen lamp, a carbon arc lamp, a tungsten lamp, a gallium lamp, an excimer laser, an LED light source emitting light in a wavelength range of 380 to 440 nm, a chemical lamp, a black light, a microwave-excited mercury lamp, a metal halide lamp, etc. can be cited.

[0239] The ultraviolet irradiation intensity is usually 10 mW / cm 2 ~3,000 mW / cm 2 . The ultraviolet irradiation intensity is preferably the intensity in a wavelength region effective for activating a cationic polymerization initiator or a radical polymerization initiator. The irradiation time of the light is usually 0.1 second to 10 minutes, preferably 1 second to 5 minutes, more preferably 5 seconds to 3 minutes, and further preferably 10 seconds to 1 minute. Irradiating once or more times with such an ultraviolet irradiation intensity, the cumulative light amount is 10 mJ / cm 2 ~3,000 mJ / cm 2 , preferably 50 mJ / cm 2 ~2,000 mJ / cm 2 , more preferably 100 mJ / cm 2 ~1,000 mJ / cm 2 . When the cumulative light amount is below this range, the curing of the polymerizable liquid crystal compound becomes insufficient, and sometimes good transferability cannot be obtained. On the contrary, when the cumulative light amount is above this range, sometimes the retardation film containing the liquid crystal cured film is colored.

[0240] In order to sufficiently cure a liquid crystal cured film having a thickness of 2.5 μm or more and reduce (S / M) / (S T / M T) value, obtain good heat resistance, and irradiate with active energy rays from both sides. When irradiating with active energy rays from both sides, irradiate from the coating film side and the substrate film side of a laminated body in which a substrate film, an alignment film, and a coating film containing a polymerizable liquid crystal compound are sequentially laminated. When irradiating with active energy rays from the substrate film side of the laminated body, the active energy rays are irradiated through the substrate film and the alignment film.

[0241] <Orientation film 3>

[0242] The alignment film has an alignment regulating force for aligning the polymerizable liquid crystal compound in a desired direction.

[0243] The orientation film makes it easy to orient the liquid crystal of the polymerizable liquid crystal compound. The state of liquid crystal orientation such as horizontal orientation, vertical orientation, mixed orientation, and tilted orientation varies according to the properties of the orientation film and the polymerizable liquid crystal compound, and the combination thereof can be selected arbitrarily. For example, if the orientation film is a material that exhibits horizontal orientation as an orientation limiting force, the polymerizable liquid crystal compound can form a horizontal orientation or a mixed orientation, and if it is a material that exhibits vertical orientation, the polymerizable liquid crystal compound can form a vertical orientation or a tilted orientation. Expressions such as horizontal and vertical indicate the direction of the optical axis of the oriented polymerizable liquid crystal compound when the plane of the liquid crystal curing film is used as a reference. For example, vertical orientation refers to an optical axis of the oriented polymerizable liquid crystal compound in a direction perpendicular to the plane of the liquid crystal curing film. The vertical mentioned here refers to 90°±20° relative to the plane of the liquid crystal curing film.

[0244] Regarding the orientation restraining force, when the orientation film is formed of an orientation polymer, it can be arbitrarily adjusted by the surface state and friction conditions, and when it is formed of a photo-orientation polymer, it can be arbitrarily adjusted by polarized light irradiation conditions, etc. In addition, the liquid crystal orientation can also be controlled by selecting the surface tension, liquid crystal properties, etc. of the polymerizable liquid crystal compound.

[0245] As an alignment film formed between the substrate film and the liquid crystal curing film, it is preferred that the alignment film is insoluble in the solvent used when the liquid crystal curing film is formed on the alignment film and has heat resistance in the heating treatment for removing the solvent and aligning the liquid crystal. As alignment films, alignment films containing alignment polymers, photoalignment films, groove alignment films, stretched films stretched along the alignment direction, etc. can be cited. In the case of being applied to a long roll film, a photoalignment film is preferred from the viewpoint of being able to easily control the alignment direction.

[0246] The thickness of the alignment film is usually in the range of 10 nm to 5000 nm, preferably in the range of 10 nm to 1000 nm, and more preferably in the range of 30 to 300 nm.

[0247] Examples of the alignment polymer used in the rubbing alignment film include: polyamides and gelatin having an amide bond in the molecule, polyimides having an imide bond in the molecule and polyamic acids as their hydrolyzates, polyvinyl alcohol, alkyl-modified polyvinyl alcohol, polyacrylamide, polyoxazole, polyethyleneimine, polystyrene, polyvinylpyrrolidone, polyacrylic acid, and polyacrylates. Among them, polyvinyl alcohol is preferred. These alignment polymers can be used alone or in combination of two or more.

[0248] Examples of the rubbing method include: a method in which a film of an alignment polymer formed on the surface of a substrate film by coating an alignment polymer composition on the substrate film and annealing is brought into contact with a rubbing roller wound with a rubbing cloth and rotating.

[0249] The photoalignment film contains a polymer, oligomer, or monomer having a photoreactive group. The photoalignment film obtains an alignment restraining force by irradiating polarized light. From the viewpoint that the direction of the alignment restraining force can be arbitrarily controlled by selecting the polarization direction of the irradiated polarized light, the photoalignment film is more preferred.

[0250] The photoreactive group means a group that generates liquid crystal alignment ability by irradiating light. Specifically, it is a group that undergoes a photoreaction such as an orientation induction or isomerization reaction, dimerization reaction, photocrosslinking reaction, or photodecomposition reaction of molecules generated by irradiating light, which is the origin of the liquid crystal alignment ability. Among these photoreactive groups, from the aspect of excellent alignment property, a group that undergoes a dimerization reaction or a photocrosslinking reaction is preferred. As the photoreactive group capable of undergoing the above reactions, a photoreactive group having an unsaturated bond, particularly a double bond, is preferred, and a group having at least one selected from a carbon-carbon double bond (C = C bond), a carbon-nitrogen double bond (C = N bond), a nitrogen-nitrogen double bond (N = N bond), and a carbon-oxygen double bond (C = O bond) is more preferred.

[0251] As the photoreactive group having a C═C bond, for example, vinyl group, polyene group, stilbenyl group, styrylpyridyl group, styrylpyrazolium group, chalcone group, cinnamoyl group, etc. can be cited. From the viewpoints of easy controllability of reactivity and orientation restricting force when exhibiting photoorientation, chalcone group and cinnamoyl group are preferred. As the photoreactive group having a C═N bond, groups having structures such as aromatic Schiff base and aromatic hydrazone can be cited. As the photoreactive group having an N═N bond, azobenzene group, azonaphthyl group, aromatic heterocyclic azo group, bisazo group, formazyl group, etc., groups having an azoxybenzene as the basic structure can be cited. As the photoreactive group having a C═O bond, benzophenone group, coumarin group, anthraquinone group, maleimide group, etc. can be cited. These groups may have substituents such as alkyl group, alkoxy group, aryl group, allyloxy group, cyano group, alkoxycarbonyl group, hydroxyl group, sulfonic acid group, and haloalkyl group.

[0252] When irradiating polarized light, it may be in the form of directly irradiating polarized light from the film surface, or in the form of irradiating polarized light from the substrate film side and transmitting the polarized light for irradiation. In addition, the polarized light is particularly preferably substantially parallel light. Regarding the wavelength of the irradiated polarized light, it is preferably a wavelength in the wavelength region where the photoreactive group of the polymer or monomer having the photoreactive group can absorb light energy. Specifically, UV (ultraviolet light) in the range of 250 to 400 nm is particularly preferred. As the light source used in this polarized light irradiation, xenon lamp, high-pressure mercury lamp, ultra-high-pressure mercury lamp, metal halide lamp, UV lasers such as KrF and ArF, etc. can be cited, and high-pressure mercury lamp, ultra-high-pressure mercury lamp, and metal halide lamp are more preferred. Since the light emission intensity of the ultraviolet light with a wavelength of 313 nm of these lamps is large, they are preferred. By making the light from the above light source pass through an appropriate polarizer for irradiation, polarized light can be irradiated. As this polarizer, a polarizing filter, Glan-Thompson, Glan-Taylor, etc. polarizing prisms, and a wire grid type polarizer can be used.

[0253] <Substrate film 4>

[0254] The substrate film is a support for forming the retardation layer. As the substrate film, from the aspect of being able to be continuously manufactured, a long strip-shaped roll film is preferred. As the resin constituting the substrate film, for example, polyolefins such as polyethylene, polypropylene, and norbornene-based polymers can be mentioned; cyclic olefin-based resins; polyvinyl alcohol; polyethylene terephthalate; polymethacrylate; polyacrylate; cellulose esters such as triacetyl cellulose, diacetyl cellulose, and cellulose acetate propionate; polyethylene naphthalate; polycarbonate; polysulfone; polyethersulfone; polyether ketone; plastics such as polyphenylene sulfide and polyphenylene ether. Among them, from the viewpoint of transparency and the like when used in optical film applications, a substrate film containing a resin selected from any one of triacetyl cellulose, cyclic olefin-based resin, polymethacrylate, and polyethylene terephthalate is more preferred.

[0255] As commercially available cellulose ester substrates, “FUJITAC Film” (manufactured by Fuji Photo Film Co., Ltd.); “KC8UX2M”, “KC8UY”, and “KC4UY” (the above are manufactured by Konica Minolta Opto, Inc.) and the like can be mentioned.

[0256] As commercially available cyclic olefin-based resins, “Topas” (registered trademark) (manufactured by Ticona (Germany)), “ARTON” (registered trademark) (manufactured by JSR Corporation), “ZEONOR (ゼオノア)” (registered trademark), “ZEONEX (ゼオネックス)” (registered trademark) (the above are manufactured by ZEON Corporation, Japan), and “APEL” (registered trademark) (manufactured by Mitsui Chemicals, Inc.) can be mentioned. Such cyclic olefin-based resins can be formed into films by known methods such as the solvent casting method and the melt extrusion method to form substrate films. Commercially available cyclic olefin-based resin substrates can also be used. As commercially available cyclic olefin-based resin substrates, “Escina(エスシーナ)” (registered trademark), “SCA40” (registered trademark) (the above are manufactured by Sekisui Chemical Co., Ltd.), “Zeonor Film” (registered trademark) (manufactured by Optes Co., Ltd.), and “Arton Film” (registered trademark) (manufactured by JSR Corporation) can be mentioned.

[0257] The thickness of the base film is preferably as thin as possible for practical processing, but if it is too thin, there is a tendency for the strength to decrease and the processability to be poor. The thickness of the base film is usually 5 to 300 μm, preferably 10 to 200 μm, more preferably 20 to 60 μm, and particularly preferably 30 to 50 μm. In particular, if the thickness of the base film is 30 μm or more, when a polymerizable liquid crystal composition is coated on the base film and dried to form a coating film, and then the polymerizable liquid crystal compound in the coating film is polymerized to form a liquid crystal cured film, there is a tendency to suppress the generation of thermal wrinkles of the base film caused by drying and irradiation with active energy rays. If it is 50 μm or less, there is a tendency for the bending resistance of the optical laminate to be further improved. In addition, by peeling off the base film and transferring the polarizing film and the liquid crystal cured film, a further thinning effect can be obtained.

[0258] The transmittance of the base film at 380 nm (the transmittance of light with a wavelength of 380 nm) is preferably 50% or more, more preferably 70% or more, further preferably 80% or more, and particularly preferably 90% or more. By making the transmittance of the base film at 380 nm 50% or more, when irradiating the coating film of the polymerizable liquid crystal composition with active energy rays from the side or both sides of the base film to form a liquid crystal cured film, it is easy to cure the coating film and the heat resistance can be improved. The transmittance of the base film at 380 nm can be measured by an ultraviolet-visible spectrophotometer (manufactured by Shimadzu Corporation, trade name: UV-2450).

[0259] The moisture permeability of the base film is preferably 50 g / m 2 ·24 h or more, more preferably 200 g / m 2 ·24 h or more, further preferably 400 g / m 2 ·24 h or more. If the moisture permeability of the base film is 50 g / m 2 ·24 h or more, the adhesion when bonding the base film to other members (a polarizing plate in Figure 1 ) with an aqueous adhesive can be improved. The moisture permeability of the base film can be measured by the following method. Using a thermo-hygrostat, under the measurement conditions of a temperature of 40 °C, a relative humidity of 90% RH, and a measurement time of 24 hours, the water vapor transmission rate is measured by the moisture permeability test method (cup method, based on JIS Z 0208). The measured water vapor transmission rate is taken as the moisture permeability [g / m 2 ·24 h] at a temperature of 40 °C and a relative humidity of 90% RH.

[0260] <Adhesive Layers 5 and 7>

[0261] The adhesive layer can have the function of bonding the base film of the retardation film to the polarizing plate and the polarizing plate to the protective film. The adhesive layer can be formed from an adhesive composition.

[0262] As an adhesive composition, for example, the following can be cited: an aqueous adhesive composition, a curable adhesive composition that is cured by irradiation with active energy rays such as heat, ultraviolet rays, visible light, electron beams, X-rays, etc. As the aqueous adhesive composition, for example, the following can be cited: a composition obtained by dissolving a polyvinyl alcohol-based resin or a urethane resin as a main component in water, a composition obtained by dispersing a polyvinyl alcohol-based resin or a urethane resin as a main component in water. The aqueous adhesive composition may further contain curable components such as polyaldehydes, melamine-based compounds, zirconium oxide compounds, zinc compounds, glyoxal compounds, water-soluble epoxy resins, and crosslinking agents. As the aqueous adhesive composition, for example, the adhesive composition described in JP-A-2010-191389, the adhesive composition described in JP-A-2011-107686, the composition described in JP-A-2020-172088, the composition described in JP-A-2005-208456, etc. can be cited.

[0263] The curable adhesive composition is preferably an active energy ray-curable adhesive composition that contains a curable (polymerizable) compound as a main component and is cured by irradiation with active energy rays. As the active energy ray-curable adhesive composition, a cationic polymerization type adhesive composition that contains a cationic polymerizable compound as a curable compound, a radical polymerization type adhesive composition that contains a radical polymerizable compound as a curable compound, a hybrid adhesive composition that contains both a cationic polymerizable compound and a radical polymerizable compound as curable compounds, etc. can be cited.

[0264] The cationic polymerizable compound is a compound or oligomer that undergoes a cationic polymerization reaction and cures by irradiation with active energy rays such as ultraviolet rays, visible light, electron beams, X-rays, etc. or by heating. Specifically, epoxy compounds, oxetane compounds, vinyl compounds, etc. can be cited.

[0265] As the epoxy compound, the following can be cited: alicyclic epoxy compounds such as 3,4-epoxycyclohexanecarboxylic acid 3’,4’-epoxycyclohexylmethyl ester (compounds having one or more epoxy groups bonded to an alicyclic ring in the molecule); aromatic epoxy compounds such as diglycidyl ether of bisphenol A (compounds having an aromatic ring and an epoxy group in the molecule); aliphatic epoxy compounds such as 2-ethylhexyl glycidyl ether, 1,4-butanediol diglycidyl ether (compounds having at least one oxirane ring bonded to an aliphatic carbon atom in the molecule), etc.

[0266] As the oxetane compound, compounds having one or more oxetane rings in the molecule such as 3-ethyl-3-{[(3-ethyl-oxetane-3-yl)methoxy]methyl}oxetane can be cited.

[0267] The cationic polymerization type adhesive composition preferably contains a cationic polymerization initiator. The cationic polymerization initiator can be a thermal cationic polymerization initiator or a photo cationic polymerization initiator. Examples of the cationic polymerization initiator include aromatic diazonium salts such as benzenediazonium hexafluoroantimonate; aromatic iodonium salts such as diphenyliodonium tetrakis(pentafluorophenyl)borate; aromatic sulfonium salts such as triphenylsulfonium hexafluorophosphate; iron-arene complexes such as dimethylbenzene-cyclopentadienyliron(II) hexafluoroantimonate. The content of the cationic polymerization initiator is usually 0.1 to 10 parts by mass relative to 100 parts by mass of the cationic polymerizable compound. Two or more cationic polymerization initiators can be included. Examples of the cationic polymerization type adhesive composition include the cationic polymerizable compositions described in JP-A-2016-126345, WO 2019 / 10315, and JP-A-2021-113969.

[0268] The radical polymerizable compound is a compound or oligomer that is cured by a radical polymerization reaction upon irradiation with active energy rays such as ultraviolet rays, visible light, electron beams, and X-rays or by heating. Specifically, compounds having an ethylenically unsaturated bond can be cited. Examples of the compound having an ethylenically unsaturated bond include (meth)acrylic compounds having one or more (meth)acryloyl groups in the molecule, vinyl compounds having one or more vinyl groups in the molecule, and the like. Examples of the (meth)acrylic compound include (meth)acrylate monomers having at least one (meth)acryloyloxy group in the molecule, (meth)acrylamide monomers, and (meth)acrylic oligomers having at least two (meth)acryloyl groups in the molecule obtained by reacting two or more functional group-containing compounds. In the present specification, the (meth)acryloyl group means either an acryloyl group or a methacryloyl group.

[0269] The radical polymerization type adhesive composition preferably contains a radical polymerization initiator. The radical polymerization initiator can be a thermal radical polymerization initiator or a photo radical polymerization initiator. Examples of the radical polymerization initiator include: acetophenone-based initiators such as acetophenone and 3-methylacetophenone; benzophenone-based initiators such as benzophenone, 4-chlorobenzophenone, and 4,4'-diaminobenzophenone; benzoin ether-based initiators such as benzoin propyl ether and benzoin ethyl ether; thioxanthone-based initiators such as 4-isopropylthioxanthone; xanthone, fluorenone, etc. The content of the radical polymerization initiator is usually 0.1 to 10 parts by mass relative to 100 parts by mass of the radical polymerizable compound. Two or more radical polymerization initiators can be included. Examples of the radical polymerization type adhesive composition include the radical polymerizable compositions described in JP-A-2016-126345, JP-A-2016-153474, and WO2017 / 183335.

[0270] The active energy ray curable adhesive composition can contain additives such as an ion scavenger, an antioxidant, a chain transfer agent, a tackifier, a thermoplastic resin, a filler, a flow regulator, a plasticizer, an antifoaming agent, an antistatic agent, a leveling agent, and a solvent as needed.

[0271] The lamination of two layers using the adhesive layer can be carried out as follows: The adhesive composition is applied to at least one of the lamination surfaces selected from the two respective lamination surfaces, the two are overlapped via the applied layer of the adhesive composition, and after being laminated by pressing from above and below using a laminating roll or the like, the adhesive layer is dried and cured by irradiating active energy rays or cured by heating.

[0272] Before forming the applied layer of the adhesive layer, an adhesion-improving treatment such as saponification treatment, corona treatment, plasma treatment, primer treatment, or anchor coating treatment can be performed on at least one of the lamination surfaces selected from the two respective lamination surfaces.

[0273] The formation of the applied layer of the adhesive composition can be carried out by various coating methods such as a die coater, a comma coater, an intaglio coater, a wire bar coater, and a knife coater.

[0274] The light irradiation intensity during the irradiation of active energy rays is determined according to the composition of the active energy ray curable adhesive composition and is not particularly limited, and is preferably 10 mW / cm 2 or more and 1,000 mW / cm 2 or less. It should be noted that the irradiation intensity is preferably the intensity in the wavelength region effective for activating the photo cationic polymerization initiator or the photo radical polymerization initiator. Irradiate once or more times with such a light irradiation intensity, and preferably make the cumulative light amount 10 mJ / cm 2 or more, more preferably 100 mJ / cm 2Above and 1,000 mJ / cm 2 or less.

[0275] The light source used for the polymerization curing of the energy ray curable adhesive composition is not particularly limited, and examples thereof include a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a halogen lamp, a chemical lamp, a black light, a microwave-excited mercury lamp, and a metal halide lamp.

[0276] The thickness of the adhesive layer formed from the aqueous adhesive composition can be, for example, 5 μm or less, preferably 1 μm or less, more preferably 0.5 μm or less, and can be 0.01 μm or more, preferably 0.05 μm or more.

[0277] The thickness of the adhesive layer formed from the energy ray curable adhesive composition can be, for example, 10 μm or less, preferably 5 μm or less, more preferably 3 μm or less, and can be 0.1 μm or more, preferably 0.5 μm or more, more preferably 1 μm or more.

[0278] <Polarizing plate 6>

[0279] As the polarizing plate, for example, a film obtained by uniaxially stretching a polyvinyl alcohol-based resin film (hereinafter, also referred to as "PVA-based film") or the like in a state where iodine or an organic dichroic dye is impregnated into the polymer can be used. The polarizing plate having the above configuration can generally be manufactured through the following steps: a step of uniaxially stretching the PVA-based film; a step of adsorbing the dichroic pigment by dyeing the PVA-based film with a dichroic pigment such as iodine; a step of treating the PVA-based film adsorbed with the dichroic pigment with a crosslinking agent such as a boric acid aqueous solution; and a step of washing with water after the treatment with a crosslinking agent such as a boric acid aqueous solution. The polarizing plate may contain a crosslinking agent.

[0280] The thickness of the polarizing plate is usually 30 μm or less, preferably 18 μm or less, more preferably 15 μm or less, and further preferably 12 μm or less. By making the thickness of the polarizing plate below the above upper limit value, the bending resistance of the optical laminate can be further improved. The thickness of the polarizing plate is usually 1 μm or more, and can also be, for example, 5 μm or more.

[0281] The uniaxial stretching of the PVA-based film can be carried out before, simultaneously with, or after the staining based on the dichroic pigment. In the case where the uniaxial stretching is carried out after the staining, the uniaxial stretching can be carried out before or during the boric acid treatment. Of course, the uniaxial stretching can also be carried out at multiple stages shown here. The uniaxial stretching can adopt methods such as uniaxially stretching along the film conveyance direction between rollers with different circumferential speeds, uniaxially stretching along the film conveyance direction using a hot roller, and stretching along the width direction using a tenter. In addition, the uniaxial stretching can be carried out by dry stretching in the atmosphere or by wet stretching in a state where the PVA-based film is swollen using a solvent such as water. The stretching ratio is usually about 3 to 8 times. In addition, an aqueous solution containing polyvinyl alcohol can be coated on the thermoplastic resin film and then dried, and the thermoplastic resin film can be stretched together by the above method.

[0282] The staining of the PVA-based film based on the dichroic pigment can be carried out, for example, by immersing the PVA-based film in an aqueous solution containing the dichroic pigment. Specifically, as the dichroic pigment, iodine or a dichroic organic dye can be used. It should be noted that the PVA-based film is preferably pre-treated by immersing it in water to swell it before the staining treatment.

[0283] In the case of using iodine as the dichroic pigment, a method of staining by immersing the PVA-based film in an aqueous solution containing iodine and potassium iodide is usually adopted. The content of iodine in this aqueous solution is usually about 0.01 to 1 part by mass per 100 parts by mass of water, and the content of potassium iodide is usually about 0.5 to 20 parts by mass per 100 parts by mass of water. The temperature of the aqueous solution used in the staining is usually about 20 to 40 °C. In addition, the immersion time (staining time) in this aqueous solution is usually about 20 to 1,800 seconds.

[0284] On the other hand, in the case of using a dichroic organic dye as the dichroic pigment, a method of staining by immersing the PVA-based film in an aqueous solution containing a water-soluble dichroic organic dye is usually adopted. The content of the dichroic organic dye in this aqueous solution is usually about 0.0001 to 10 parts by mass per 100 parts by mass of water, preferably 0.001 to 1 part by mass. This dye aqueous solution can contain an inorganic salt such as sodium sulfate as a staining aid. The temperature of the dichroic organic dye aqueous solution used in the staining is usually about 20 to 80 °C. In addition, the immersion time (staining time) in this aqueous solution is usually about 10 to 1,800 seconds.

[0285] The boric acid treatment after dyeing with dichroic dyes can be carried out by immersing the dyed PVA-based film in an aqueous solution containing boric acid. The content of boric acid in the aqueous solution containing boric acid is usually about 2 to 15 parts by mass, preferably 5 to 12 parts by mass, per 100 parts by mass of water. When iodine is used as the dichroic dye, the aqueous solution containing boric acid preferably contains potassium iodide. The content of potassium iodide in the aqueous solution containing boric acid is usually about 0.1 to 15 parts by mass, preferably 5 to 12 parts by mass, per 100 parts by mass of water. The immersion time in the aqueous solution containing boric acid is usually about 60 to 1,200 seconds, preferably 150 to 600 seconds, and more preferably 200 to 400 seconds. The temperature of the aqueous solution containing boric acid is usually 50°C or higher, preferably 50 to 85°C, and more preferably 60 to 80°C.

[0286] The PVA-based film after boric acid treatment is usually subjected to a water washing treatment. The water washing treatment can be carried out, for example, by immersing the PVA-based film after boric acid treatment in water. The temperature of the water in the water washing treatment is usually about 5 to 40°C. In addition, the immersion time is usually about 1 to 120 seconds.

[0287] After water washing, a drying treatment is carried out to obtain a polarizing plate. The drying treatment can be carried out using a hot air dryer or a far-infrared heater. The temperature of the drying treatment is usually about 30 to 100°C, preferably 50 to 80°C. The time of the drying treatment is usually about 60 to 600 seconds, preferably 120 to 600 seconds. By the drying treatment, the moisture rate in the polarizing plate is reduced to a practical level. The moisture rate is usually about 5 to 20 mass%, preferably 8 to 15 mass%, relative to the total mass of the polarizing plate. If the moisture rate is 5 mass% or more, the polarizing plate has sufficient flexibility, so that damage or breakage after drying can be suppressed. In addition, if the moisture rate is 20 mass% or less, the polarizing plate has sufficient thermal stability.

[0288] As described above, it is possible to manufacture a polarizing plate in which dichroic dyes are adsorbed and oriented on a PVA-based film.

[0289] The polarization performance of the polarizing plate can be measured using a spectrophotometer. For example, in the visible light range of wavelengths 380 nm to 780 nm, using a device equipped with a prism polarizing plate on the spectrophotometer, the transmittance (T 1 in the direction of the transmission axis (perpendicular to the orientation direction) and the transmittance (T 2). Regarding the polarization performance in the visible light range, the single transmittance and polarization degree at each wavelength are calculated using the following formulas (Formula 1) and (Formula 2), and the visibility (Japanese: visual sensitivity) correction is further performed using the 2-degree field of view (C light source) of JIS Z 8701, thereby being able to calculate the visibility-corrected single transmittance (Ty) and the visibility-corrected polarization degree (Py). In addition, based on the transmittance measured in the same way, the color matching function (Japanese: color matching function) of the C light source is used to calculate L ＊ a ＊ b ＊ Chromaticity a in the (CIE) color system ＊ and b ＊ , which can obtain the color tone of the polarizer alone (single color tone), the color tone of the polarizers arranged in parallel (parallel color tone), and the color tone of the polarizers arranged orthogonally (orthogonal color tone). ＊ and b ＊ The closer the value is to 0, the more neutral the color tone can be judged to be.

[0290] Single body transmittance (%) = (T 1 +T 2 ) / 2 …(Formula 1)

[0291] Polarization degree (%) = (T 1 -T 2 ) / (T 1 +T 2 )×100 …(Formula 2)

[0292] The visibility correction polarization degree Py of polaroid is usually more than 80%, preferably more than 90%, more preferably more than 95%, more preferably more than 98%, particularly preferably more than 99%, if more than 99.9%, then can be suitably used for liquid crystal display.Improving the visibility correction polarization degree Py of polaroid is beneficial to improving the anti-reflection function of optical laminate.If the visibility correction polarization degree Py is less than 80%, then sometimes can not play the anti-reflection function when used as anti-reflection film.

[0293] The higher the visible light transmittance Ty of the visibility correction monomer of the polarizer, the clearer the white display becomes. However, from the relationships in (Equation 1) and (Equation 2), if the monomer transmittance is excessively increased, there is a problem of a decrease in the degree of polarization. Therefore, the visible light transmittance Ty of the visibility correction monomer is preferably 30% or more, more preferably 35% or more, further preferably 38% or more, and particularly preferably 40% or more. In addition, the visible light transmittance Ty of the visibility correction monomer is preferably 60% or less, more preferably 55% or less, and further preferably 50% or less. From the viewpoint of improving the reflection color tone, it is particularly preferably 43% or more and 46% or less. If the visible light transmittance Ty of the visibility correction monomer is too high, the polarization degree Py of the visibility correction becomes too low, and sometimes the antireflection function when used as an antireflection film becomes insufficient.

[0294] <Protective film 8>

[0295] The protective film has a function of protecting the surface of the polarizer. The polarizer and the protective film can be directly laminated to each other. Here, "directly laminated" includes a method of laminating on the polarizer by the self-adhesiveness of the protective film, and a method of laminating on the polarizer via an adhesive layer or an adhesive layer. In order to improve the adhesion to the polarizer, the protective film can be subjected to surface treatment (for example, corona treatment, etc.), or a thin layer such as a primer layer (also called an easy-adhesion layer) can be formed.

[0296] As the protective film, for example, a resin film excellent in transparency, mechanical strength, thermal stability, moisture barrier property, isotropy, stretchability, etc. can be used. The resin film can be a thermoplastic resin film. Specific examples of such resins include: cellulose-based resins such as triacetyl cellulose; polyester-based resins such as polyethylene terephthalate and polyethylene naphthalate; polyethersulfone-based resins; polysulfone-based resins; polycarbonate-based resins; polyamide-based resins such as nylon and aromatic polyamide; polyimide-based resins; polyolefin-based resins such as polyethylene, polypropylene, and ethylene-propylene copolymer; cyclic polyolefin-based resins (also called norbornene-based resins) having a ring system and a norbornene structure; (meth)acrylic-based resins such as polymethyl methacrylate; polyarylate-based resins; polystyrene-based resins; polyvinyl alcohol-based resins, and mixtures thereof. The protective film of this material can be easily obtained from the market. In addition, thermosetting resins such as (meth)acrylic-based, urethane-based, (meth)acrylic urethane-based, epoxy-based, and silicone-based resins, or ultraviolet curable resins can also be mentioned. In this specification, (meth)acrylic refers to either acrylic acid or methacrylic acid.

[0297] As a chain polyolefin resin, in addition to homopolymers of chain olefins such as polyethylene resin (polyethylene resin as a homopolymer of ethylene, copolymer mainly composed of ethylene), polypropylene resin (polypropylene resin as a homopolymer of propylene, copolymer mainly composed of propylene), copolymers containing two or more kinds of chain olefins can also be cited.

[0298] The cyclic polyolefin resin is a general term for resins polymerized with cyclic olefins as polymerization units. For example, resins described in JP-A-1-240517, JP-A-3-14882, JP-A-3-122137, etc. can be cited. If specific examples of the cyclic polyolefin resin are listed, they are ring-opening (co)polymers of cyclic olefins, addition polymers of cyclic olefins, copolymers of cyclic olefins and chain olefins such as ethylene and propylene (typically random copolymers), graft polymers obtained by modifying them with unsaturated carboxylic acids and their derivatives, and their hydrides. Among them, it is preferable to use norbornene-based resins using norbornene-based monomers such as norbornene and polycyclic norbornene-based monomers as cyclic olefins.

[0299] The polyester resin is a resin having an ester bond in the main chain and is usually a condensate of a polycarboxylic acid or its derivative and a polyol. As the polycarboxylic acid or its derivative, a divalent dicarboxylic acid or its derivative can be used. For example, terephthalic acid, isophthalic acid, dimethyl terephthalate, dimethyl naphthalate, etc. can be cited. As the polyol, a divalent diol can be used. For example, ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, cyclohexanedimethanol, etc. can be cited. As a representative example of the polyester resin, polyethylene terephthalate as a condensate of terephthalic acid and ethylene glycol can be cited.

[0300] The cellulose ester resin is an ester of cellulose and a fatty acid. Specific examples of the cellulose ester resin include cellulose triacetate, cellulose diacetate, cellulose tripropionate, cellulose dipropionate. In addition, copolymers having a plurality of polymerization units constituting these cellulose ester resins and cellulose ester resins in which a part of the hydroxyl groups are modified with other substituents can also be cited. Among them, cellulose triacetate (triacetyl cellulose) is particularly preferable.

[0301] The (meth)acrylic resin is a resin mainly composed of a compound having a (meth)acryloyl group. Specific examples of the (meth)acrylic resin include, for example, poly(meth)acrylates such as polymethyl methacrylate; methyl methacrylate-(meth)acrylic acid copolymer; methyl methacrylate-(meth)acrylate copolymer; methyl methacrylate-acrylate-(meth)acrylic acid copolymer; (meth)acrylate-methyl styrene copolymer (such as MS resin); copolymer of methyl methacrylate and a compound having an alicyclic hydrocarbon group (for example, methyl methacrylate-methyl cyclohexyl methacrylate copolymer, methyl methacrylate-(meth)acrylate norbornene copolymer, etc.). A polymer mainly composed of poly(meth)acrylic acid C1-6 alkyl ester such as polymethyl methacrylate is preferably used, and a methyl methacrylate resin mainly composed of methyl methacrylate (50 to 100% by mass, preferably 70 to 100% by mass) is more preferably used.

[0302] The polycarbonate resin is a polymer in which monomer units are bonded via a carbonate group. The polycarbonate resin may be a resin called a modified polycarbonate in which the polymer skeleton is modified, a copolycarbonate, etc. Details of the polycarbonate resin are described, for example, in Japanese Patent Application Laid-Open No. 2012-31370. The description of this patent document is incorporated herein by reference.

[0303] In the present invention, the substrate film used as the support of the liquid crystal cured film is then adhered to the polarizing plate and functions as a protective film for protecting one surface of the polarizing plate. Thereby, the manufacturing process of the optical laminate can be reduced.

[0304] The thickness of the protective film is preferably 0.1 μm to 60 μm, more preferably 0.5 μm to 40 μm, and further preferably 1 μm to 30 μm.

[0305] From the viewpoint of improving the reflection color tone, the 380 nm transmittance (transmittance of light with a wavelength of 380 nm) of the protective film is preferably 10% or less, more preferably 7% or less, further preferably 5% or less, particularly preferably 3% or less, and extremely preferably 1.5% or less. By making the 380 nm transmittance of the protective film 10% or less, the weather resistance of the optical laminate can be improved. The 380 nm transmittance of the protective film can be measured by the same method as the 380 nm transmittance of the substrate film.

[0306] The protective film can be disposed and used in a manner closer to the viewing side than the polarizing plate. Therefore, surface treatments such as hard coat treatment, antireflection treatment, anti-sticking treatment, antiglare treatment, etc. can be applied to the protective film as needed. Further / alternatively, the following treatment can also be applied to the protective film as needed, that is, a treatment for improving the visibility when viewing through polarized sunglasses (typically, imparting an (elliptical) polarization function, imparting an ultra-high retardation). By applying such a treatment, excellent visibility can be achieved even when viewing a display screen through a polarized lens such as polarized sunglasses. Therefore, an optical laminate having a protective film to which such a treatment has been applied can also be suitably applied to an image display device that can be used outdoors.

[0307] By stretching the film containing the above thermoplastic resin, a protective film can be produced. Examples of the stretching treatment include uniaxial stretching and biaxial stretching. Examples of the stretching direction include the machine flow direction (MD) of the unstretched film, the direction orthogonal thereto (TD), and the direction obliquely intersecting the machine flow direction (MD). Biaxial stretching can be simultaneous biaxial stretching in which stretching is performed simultaneously in two stretching directions, or sequential biaxial stretching in which stretching is performed in a specified direction and then in another direction. The stretching treatment can be performed, for example, by using two or more pairs of pinch rollers with an increased circumferential speed on the outlet side to stretch in the length direction (machine flow direction: MD), or by gripping both end portions of the unstretched film with chucks and expanding in the direction orthogonal to the machine flow direction (TD). At this time, by adjusting the film thickness or the stretching ratio, the retardation value and the wavelength dispersion can be controlled. In addition, by adding a wavelength dispersion regulator to the resin, the wavelength dispersion value can be controlled.

[0308] The protective film can contain any suitable additives according to the purpose. Examples of the additives include antioxidants such as hindered phenol-based, phosphorus-based, and sulfur-based antioxidants, light stabilizers, ultraviolet absorbers, weather stabilizers, heat stabilizers, etc.; reinforcing materials such as glass fibers and carbon fibers; near-infrared absorbers; flame retardants such as tris(dibromopropyl) phosphate, triallyl phosphate, and antimony oxide; antistatic agents such as anionic, cationic, and nonionic surfactants; colorants such as inorganic pigments, organic pigments, and dyes; organic fillers, inorganic fillers; resin modifiers; plasticizers; lubricants; retardation reducing agents, etc. The type, combination, content, etc. of the additives contained can be appropriately set according to the purpose and the desired properties.

[0309] In addition, in order to impart desired surface optical properties or other characteristics, a coating layer (surface treatment layer) may be provided on the outer surface of the protective film. Specific examples of the surface treatment layer include a hard coat layer, an antiglare layer, an antireflection layer, an antistatic layer, and an antifouling layer. The method for forming the surface treatment layer is not particularly limited, and known methods can be used. The surface treatment layer may be formed on one side of the protective film or on both sides.

[0310] The hard coat layer has the function of improving the surface hardness of the protective film and is provided for the purpose of preventing scratches on the surface. The pencil hardness of the hard coat layer is preferably H or harder as measured by the pencil hardness test specified in JIS K 5600-5-4:1999 "General Test Methods for Paints - Part 5: Mechanical Properties of Film Coatings - Section 4: Scratch Hardness (Pencil Method)" (measured with the optical film having the hard coat layer placed on a glass plate).

[0311] The material for forming the hard coat layer is usually a material that cures by heat or light. For example, silicone-based, melamine-based, epoxy-based, (meth)acrylic-based, urethane (meth)acrylate-based organic hard coat materials, and inorganic hard coat materials such as silica can be cited. Among them, urethane (meth)acrylate-based or polyfunctional (meth)acrylate-based hard coat materials are preferably used in terms of good adhesion to the protective film and excellent productivity. In this specification, (meth)acrylate means either acrylate or methacrylate.

[0312] For the purpose of achieving refractive index adjustment, improvement of flexural modulus, stabilization of volume shrinkage rate, and even improvement of heat resistance, antistatic property, antiglare property, etc., the hard coat layer may contain various fillers as desired. In addition, the hard coat layer may also contain additives such as antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, leveling agents, and defoaming agents.

[0313] In order to further improve the strength, the hard coat layer may contain additives. The additives are not limited, and inorganic fine particles, organic fine particles, or a mixture thereof can be cited. In addition, for it to have hardness, the thicker the thickness of the hard coat layer, the better, but if it is too thick, it is likely to crack during cutting, so it can be 1 μm to 20 μm, or it can be 2 μm to 10 μm. The thickness of the hard coat layer is preferably 3 μm to 7 μm.

[0314] The antiglare layer is a layer having a fine concavo-convex shape on the surface, and it is preferably formed using the above-mentioned hard coat material.

[0315] The antiglare layer having fine uneven shapes on the surface can be formed in the following ways: 1) a method of forming a coating film containing fine particles on the protective film and setting the unevenness based on the fine particles; 2) a method of transferring the uneven shape by pressing a coating film containing or not containing fine particles on the protective film against a mold (such as a roller) having an uneven shape on the surface (also called an embossing method), etc.

[0316] The antireflection layer is a layer for weakening the external light reflection on the surface of the protective film for a person observing the protective film, and typically has a reflectance of 1.5% or less for visible light. Such an antireflection layer with such a reflectance can typically be formed by laminating a high refractive index layer having a high refractive index and a low refractive index layer having a low refractive index, or by using the methods and materials described in Japanese Patent Application Laid-Open No. 2021-6929. By adjusting their refractive indices and the thicknesses of the respective layers, the reflected light from each layer can be weakened from each other, achieving an excellent antireflection function.

[0317] As will be described in detail later, the antireflection layer containing a high refractive index layer and a low refractive index layer is preferably manufactured using a coating type composition capable of separately forming a high refractive index layer and a low refractive index layer because the operation is extremely simple. Here, an example of a coating type composition capable of separately forming a high refractive index layer and a low refractive index layer is given. This coating type composition is liquid and contains a suitable curable resin and additives as needed. The coating type composition for forming a high refractive index layer (composition for forming a high refractive index layer) is, for example, a solution obtained by dissolving a curable resin such as urethane acrylate and a photoinitiator for photopolymerization (photoinitiator) such as acetophenone-based, benzophenone-based, benzil dimethyl ketal-based, α-hydroxyalkylbenzophenone-based, α-aminoalkylbenzophenone-based, thioxanthone-based in a solvent such as methyl ethyl ketone and methyl isobutyl ketone. In order to make the coating property better, a leveling agent, preferably a fluorine-based leveling agent, can be contained. In addition, as the coating type composition for forming a low refractive index layer (composition for forming a low refractive index layer), it is a dispersion of silica particles in a solution obtained by dissolving a photoinitiator for photopolymerization (photoinitiator) such as acetophenone-based, benzophenone-based, benzil dimethyl ketal-based, α-hydroxyalkylbenzophenone-based, α-aminoalkylbenzophenone-based, thioxanthone-based in a solvent such as 1-methoxy-2-propyl acetate and methyl isobutyl ketone in a binder resin such as polyethylene glycol diacrylate and pentaerythritol (tri / tetra) acrylate as a curable resin. In order to make the coating property better, a fluorine-based leveling agent can be contained. It should be noted that the coating type compositions for separately forming a high refractive index layer and a low refractive index layer listed here are only examples, and it is preferable to optimize the composition for forming a high refractive index layer and the composition for forming a low refractive index layer respectively according to the characteristics of the antireflection layer to be formed.

[0318] The antireflection layer may, for example, include a low refractive index layer. Alternatively, it may be a multilayer structure further including a high refractive index layer and / or a medium refractive index layer between the protective film and the low refractive index layer.

[0319] The low refractive index layer can be formed by coating a coating liquid containing a cured product of the above curable resin, a light-transmitting resin such as a metal alkoxide polymer, and inorganic particles, and then curing the coating layer as needed. Examples of the inorganic particles include low refractive particles such as LiF (refractive index 1.4), MgF (refractive index 1.4), 3NaF·AlF (refractive index 1.4), AlF (refractive index 1.4), Na3AlF6 (refractive index 1.33), and hollow silica particles.

[0320] The antistatic layer is provided for the purpose of imparting conductivity to the surface of the protective film and suppressing the influence caused by static electricity. For example, the antistatic layer can be formed by coating a resin composition containing a conductive substance (antistatic agent) on the protective film. For example, an antistatic hard coating can be formed by making the antistatic agent coexist with the hard coating material used in the formation of the above hard coating.

[0321] The antifouling layer is provided to impart hydrophobicity, oleophobicity, sweat resistance, antifouling properties, etc. Suitable materials for forming the antifouling layer are fluorine-containing organic compounds. Examples of the fluorine-containing organic compounds include fluorocarbons, perfluorosilanes, and their high molecular compounds. The formation method of the antifouling layer can be a physical vapor deposition method represented by evaporation and sputtering, a chemical vapor deposition method, a wet coating method, etc., depending on the material to be formed. The average thickness of the antifouling layer is usually about 1 to 50 nm, preferably 3 to 35 nm.

[0322] <Optical laminate 100>

[0323] From the viewpoint of obtaining good flex resistance, the total thickness of the optical laminate having the above-described layers can be 70 μm or more, preferably 80 μm or more. Additionally, it can be 150 μm or less, preferably 120 μm or less.

[0324] In addition, the ratio of the thickness of the liquid crystal cured film to the total thickness of the optical laminate can be 2.15% or more. By making the above ratio 2.15% or more, the generation of interference unevenness can be suppressed, and high flex resistance can be obtained. From the above viewpoint, the ratio of the thickness of the liquid crystal cured film to the total thickness of the optical laminate is preferably 2.3% or more, more preferably 2.5% or more. In addition, the ratio of the thickness of the liquid crystal cured film to the total thickness of the optical laminate can be 5% or less, can be 4% or less, can be 3.5% or less, and can also be 3% or less.

[0325] The optical laminate may include a separator for protecting the outer surface of the adhesive layer. The separator is a film temporarily adhered to protect the surface of the adhesive layer until the adhesive layer is adhered to an image display element (such as an organic EL display element) or other optical member. The thickness of the separator is not included in the "total thickness of the optical laminate". The separator is usually composed of a thermoplastic resin film having a release treatment based on a silicone-based, fluorine-based, or other release agent on one side, and the release-treated surface is adhered to the adhesive layer.

[0326] Examples of the thermoplastic resin constituting the separator include polyethylene-based resins such as polyethylene, polypropylene-based resins such as polypropylene, polyester-based resins such as polyethylene terephthalate and polyethylene naphthalate.

[0327] The thickness of the separator is, for example, 10 μm or more and 100 μm or less. If the thickness of the separator is 100 μm or less, the force caused by peeling the separator can be suppressed to a low level, which is advantageous for peeling. If it is 10 μm or more, indentations on the adhesive layer caused by foreign matters during processing can be suppressed, so it is preferred.

[0328] In addition, the film formed of a polyester-based resin may or may not be stretched. From the viewpoint of improving strength, a stretched film is preferred, and it can be uniaxially stretched or biaxially stretched.

[0329] The separator may include an antistatic layer. The antistatic layer can be provided, for example, on the surface of the separator opposite to the surface where the adhesive layer is laminated.

[0330] [Manufacturing method of optical laminate]

[0331] The manufacturing method of the optical laminate of the present embodiment is a manufacturing method of an optical laminate having a protective film, a polarizing plate, a substrate film, and a liquid crystal cured film in sequence, and has a step of manufacturing the liquid crystal cured film by the manufacturing method of the liquid crystal cured film. By this manufacturing method, a liquid crystal cured film with a low value of (S / M) / (S T / M T ) can be formed, so the optical laminate can have high heat resistance.

[0332] [Image display device]

[0333] The image display device includes the above optical laminate and an image display element (such as an organic EL display element). The optical laminate is disposed on the viewing side of the image display element. The optical laminate can be adhered to the image display element via the above adhesive layer.

[0334] The image display device is not particularly limited, and examples thereof include organic electroluminescence (organic EL) display devices, inorganic electroluminescence (inorganic EL) display devices, liquid crystal display devices, electroluminescence display devices, and other image display devices.

[0335] The image display device can be used as a mobile device such as a smartphone or a tablet computer, a television, a digital photo frame, an electronic signboard, a measuring instrument or a metering instrument, an office equipment, a medical device, an electronic computing device, etc.

[0336]

Example

[0337] Hereinafter, examples and comparative examples will be shown to further specifically illustrate the present invention, but the present invention is not limited to these examples. Hereinafter, "parts" and "%" indicating the amount used or the content are based on mass unless otherwise specified.

[0338] [Example 1]

[0339] <Production of liquid crystal cured film>

[0340] (1)Preparation of photo-alignment film-forming composition

[0341] 2 parts of polymer (1) having a number average molecular weight of 28,000 represented by the following formula (1) and 98 parts of o-xylene were mixed, and the resulting mixture was stirred at 80 ° C for 1 hour to obtain a photo-alignment film-forming composition.

[0342]

Chemical formula 8

[0343]

[0344] [In the formula, Me represents a methyl group.]

[0345] (2)Preparation of polymerizable liquid crystal composition (A) for forming a liquid crystal cured film

[0346] 86.0 parts of a polymerizable liquid crystal compound A-1 represented by the following formula (A-1), 14.0 parts of a polymerizable liquid crystal compound A-2 represented by the following formula (A-2), a polyacrylate compound (a leveling agent, manufactured by BYK-Chemie, trade name: BYK-361N) (0.12 part), 2-dimethylamino-2-benzyl-1-(4-morpholinophenyl)butan-1-one (a photopolymerization initiator, manufactured by Ciba Specialty Chemicals, trade name: Irgacure 369) (3.0 parts), and LALOMER LR9000 (trade name, manufactured by BASF Japan) (2.0 parts) were mixed. Further, anisole was added so that the solid content concentration became 9%. A polymerizable liquid crystal composition (A) containing the polymerizable liquid crystal compound A-1 and the polymerizable liquid crystal compound A-2 was obtained. The polymerizable liquid crystal compound A-1 was synthesized by the method described in JP-A-2010-31223. The maximum absorption wavelength λmax(LC) of the polymerizable liquid crystal compound A-1 measured in chloroform was 350 nm.

[0347]

Chemical formula 9

[0348]

[0349]

Chemical formula 10

[0350]

[0351] (3) Production of the retardation film

[0352] Using a corona treatment device (manufactured by Kasuga Electric Co., Ltd., trade name: AGF-B10), a triacetyl cellulose film (manufactured by KONICA MINOLTA, trade name: KC4CZ-TAC, thickness 40 μm) was treated once under the conditions of an output power of 0.3 kW and a treatment speed of 3 m / minute to produce a base film. The transmittance of the base film at 380 nm was 91%, and the moisture permeability was 700 g / m 2 ·24 hr. The above composition for forming a photo-aligned film was coated on the surface of the base film subjected to corona treatment using a bar coater, dried at 80°C for 1 minute, and subjected to polarized UV exposure using a polarized UV irradiation device (SPOT CURE SP-7 (trade name) with a polarizer unit, manufactured by USHIO Inc.) with a cumulative light amount of 100 mJ / cm 2 to form a photo-aligned film. The thickness of the obtained photo-aligned film was measured with an ellipsometer M-220 (trade name, manufactured by JASCO Corporation), and the result was 100 nm.

[0353] Next, the previously prepared polymerizable liquid crystal composition (A) containing a polymerizable liquid crystal compound was coated on the above-mentioned photo-aligned film using a bar coater, and dried at 120 °C for 1 minute to form a coating film containing the polymerizable liquid crystal compound, thereby obtaining a laminate composed of a triacetyl cellulose film (substrate film) / photo-aligned film / coating film. Then, using a high-pressure mercury lamp (manufactured by USHIO Inc., trade name: Unicure VB-15201BY-A), ultraviolet rays were irradiated onto the coating film from the side facing the coating film of the above laminate (in a nitrogen atmosphere, cumulative light amount at a wavelength of 313 nm: 500 mJ / cm 2 ), and further, ultraviolet rays were irradiated from the side of the substrate film of the above laminate under the same conditions, thereby curing the coating film to form a liquid crystal cured film. Thus, a retardation film was formed as a laminate composed of a triacetyl cellulose film (substrate film) / photo-aligned film / liquid crystal cured film. The thickness of the obtained liquid crystal cured film was measured using a laser microscope (manufactured by Olympus Corporation, trade name: LEXT), and the result was 2.7 μm. The value of (S / M) / (S T / M T ) in the extraction liquid chromatography measurement of the liquid crystal cured film was 4.2. The extraction liquid chromatography measurement was performed in the state of the retardation film, which is a laminate composed of a substrate film / photo-aligned film / liquid crystal cured film. In addition, the retardation film used was a retardation film that had been formed by curing the coating film by ultraviolet irradiation to form a liquid crystal cured film and had passed more than 24 hours. The measurement method of the extraction liquid chromatography measurement was as described above.

[0354] <Fabrication of Optical Laminate>

[0355] (4) Fabrication of Polarizer 1 (Iodine PVA Type Polarizer)

[0356] (Swelling Treatment Process)

[0357] A polyvinyl alcohol film (raw material film) with a thickness of 30 μm (manufactured by Kuraray Co., Ltd., average degree of polymerization 2400, saponification degree 99.9 mol%) was continuously unwound from the original roll and conveyed while being immersed in a swelling bath containing pure water at 20 °C for 30 seconds. In this swelling treatment process, the draw ratio based on the raw material film was set to 2.5 times.

[0358] (Dyeing Treatment Process)

[0359] Next, the film after the swelling treatment process was immersed in a dyeing bath at 30 °C with a mass ratio of pure water / potassium iodide / iodine / boric acid of 100 / 2 / 0.01 / 0.3 for 120 seconds. In this dyeing treatment process, the draw ratio based on the film after the swelling treatment process was set to 1.1 times.

[0360] (Crosslinking Treatment Process)

[0361] Next, the film after the dyeing treatment process was immersed in a crosslinking bath at 56°C with a mass ratio of pure water / potassium iodide / boric acid of 100 / 12 / 4 for 70 seconds. In this crosslinking treatment process, the draw ratio based on the film after the dyeing treatment process was set to 1.9 times.

[0362] (Complementary color treatment process)

[0363] Next, the film after the crosslinking treatment process was immersed in a crosslinking bath at 40°C with a mass ratio of potassium iodide / boric acid / pure water of 9 / 2.9 / 100 for 10 seconds.

[0364] (Cleaning treatment process)

[0365] Next, the film after the complementary color treatment process was immersed in a cleaning bath containing pure water at 5°C for 5 seconds.

[0366] (Drying treatment process)

[0367] Next, the film after the cleaning treatment process was passed through a drying furnace, and thus heated and dried at 80°C for 190 seconds to produce a polarizer 1 (polarizing film). The thickness of the obtained polarizer 1 was 12 μm. The visible light correction monomer transmittance Ty of the polarizer 1 was 44.5%.

[0368] (5) Preparation of an aqueous adhesive

[0369] 3 parts by mass of carboxyl-modified polyvinyl alcohol (manufactured by Kuraray Co., Ltd., trade name: KL-318) was dissolved in 100 parts by mass of water to prepare an aqueous polyvinyl alcohol solution. Water-soluble polyamide epoxy resin (manufactured by Taoka Chemical Industry Co., Ltd., trade name: Sumirez Resin 650(30), solid content concentration 30 mass%) was mixed in the obtained aqueous solution at a ratio of 1.5 parts by mass per 100 parts by mass of water to obtain an aqueous adhesive (dry-curing type adhesive).

[0370] (6) Production of an adhesive sheet

[0371] (6-1) Preparation of an acrylic resin solution

[0372] Into a reaction vessel equipped with a condenser tube, a nitrogen inlet tube, a thermometer, and a stirrer, a mixed solution of 81.8 parts of ethyl acetate, 98.0 parts of butyl acrylate, and 2.0 parts of acrylic acid was charged. While displacing the air in the apparatus with nitrogen to make it oxygen-free, the internal temperature was raised to 55°C. Then, a solution prepared by dissolving 0.14 part of azobisisobutyronitrile (polymerization initiator) in 10 parts of ethyl acetate was added in its entirety. After adding the polymerization initiator, it was maintained at this temperature for 1 hour. Then, while maintaining the internal temperature at 54 - 56°C, ethyl acetate was continuously added to the reaction vessel at an addition rate of 17.3 parts / hr. The addition of ethyl acetate was stopped when the concentration of the (meth)acrylic resin reached 35% by mass, and it was further kept at this temperature until 12 hours had elapsed since the start of the addition of ethyl acetate. Finally, ethyl acetate was added for adjustment so that the concentration of the (meth)acrylic resin became 20% by mass, and an acrylic resin solution was prepared. The weight-average molecular weight Mw of the obtained acrylic resin was 1.8 million, and the molecular weight distribution Mw / Mn was 4.2. It should be noted that Mw and Mn were measured as follows: Two columns of "TSKgel GMH" manufactured by Tosoh Corporation were connected in series in a GPC apparatus, and tetrahydrofuran was used as the eluent. Under the conditions of a sample concentration of 2 mg / mL, a sample injection volume of 100 μL, a temperature of 40°C, and a flow rate of 1 mL / minute, the measurement was carried out by conversion with standard polystyrene. HR -H(S)" as columns, and tetrahydrofuran was used as the eluent. Under the conditions of a sample concentration of 2 mg / mL, a sample injection volume of 100 μL, a temperature of 40°C, and a flow rate of 1 mL / minute, the measurement was carried out by conversion with standard polystyrene.

[0373] (6 - 2) Preparation of the Adhesive Composition

[0374] Relative to 80 parts of the solid content of the acrylic resin solution obtained in (6 - 1), 20 parts (solid content) of a difunctional acrylate (obtained from Shin-Nakamura Chemical Co., Ltd., product number "A-DOG"), 3.0 parts of a crosslinking agent (manufactured by Tosoh Corporation, trade name "Coronate L" (ethyl acetate solution of trimethylolpropane adduct of toluene diisocyanate (solid content concentration 75% by mass))) based on the active ingredient, 1.5 parts of a photoinitiator (manufactured by Ciba Specialty Chemicals, trade name "Irgacure 500"), and 0.5 part of a silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., trade name "KBM-403") were added. Further, ethyl acetate was added to make the solid content concentration 13% by mass, and an adhesive composition was obtained. Here, A-DOG is a diacrylate of an acetal compound of hydroxypivalaldehyde and trimethylolpropane and has the structure of the following formula.

[0375] [Chemical Formula 11]

[0376]

[0377] Production of the adhesive sheet (6-3)

[0378] Using an applicator, the adhesive composition prepared in the above (6-2) was applied to the release-treated surface of a separator made of a polyethylene terephthalate film (''PLR-382150'' obtained from LINTEC Corporation) so that the thickness after drying became 25 μm, and dried at 100°C for 1 minute to produce an adhesive layer (adhesive sheet). Next, the surface of the obtained adhesive layer on the side opposite to the separator was bonded to the release-treated surface of a separator made of a release-treated polyethylene terephthalate film (''PLZ-381130'' obtained from LINTEC Corporation). Then, the adhesive layer was irradiated with ultraviolet rays under the following conditions to produce an adhesive sheet.

[0379] <UV irradiation conditions>

[0380] · Using a Fusion UV lamp system (manufactured by Fusion UV Systems Inc.) D Bulb

[0381] · Cumulative light amount: 1500 mJ / cm 2

[0382] (7)Production of the transparent protective film 1

[0383] As the transparent protective film 1, a triacetyl cellulose film (hereinafter sometimes referred to as ''TAC film''), which has a hard coat containing an ultraviolet absorber (hereinafter sometimes referred to as ''NUV-HC layer''), was prepared as a surface treatment layer as described below.

[0384] (Preparation of the surface treatment layer composition)

[0385] As the surface treatment layer composition, 20 parts of EBECRYL4858 (manufactured by DAICEL-ALLNEX), 0.80 part of UVA-01 synthesized in Synthesis Example 1 below, 0.21 part of Irgacure-184 (manufactured by BASF Japan Ltd.), 26 parts of cyclopentanone (manufactured by Kanto Chemical Co., Inc.), and 24 parts of N-methyl-2-pyrrolidone (manufactured by Kanto Chemical Co., Inc.) were mixed and stirred at room temperature for 2 hours to obtain a homogeneous solution.

[0386] (Synthesis Example 1)

[0387] A 200 mL four-necked flask equipped with a Dimroth condenser and a thermometer was set under a nitrogen atmosphere. 10 g of the compound UVA-M-02 powder represented by the following formula synthesized by referring to Patent Document (Japanese Patent Application Laid-Open No. 2014-194508), 3.7 g of acetic anhydride (manufactured by Wako Pure Chemical Industries, Ltd.), 5.8 g of 2-ethoxyethyl cyanoacetate (manufactured by Tokyo Chemical Industry Co., Ltd.), and 60 g of acetonitrile (manufactured by Wako Pure Chemical Industries, Ltd.) were charged and stirred with a magnetic stirrer. At an internal temperature of 25 °C, 4.7 g of N,N-diisopropylethylamine (hereinafter simply referred to as "DIPEA", manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise from a dropping funnel over 1 hour. After the addition was completed, the mixture was further kept at an internal temperature of 25 °C for 2 hours. After the reaction was completed, acetonitrile was removed using a rotary evaporator. Toluene was added to the resulting oily substance, and the insoluble components formed were removed by filtration. The filtrate was concentrated again using a rotary evaporator, and the concentrated solution was subjected to column chromatography (silica gel) for purification and recrystallization from toluene to obtain the target product. The crystals were dried under reduced pressure at 60 °C to obtain 5.2 g of compound UVA-01 in the form of a yellow powder. The yield was 65%. In addition, the absorption maximum wavelength (λmax) of UVA-01 was measured using a spectrophotometer UV-3150 (manufactured by Shimadzu Corporation). As a result, λmax = 389 nm (in 2-butanone), ε(400) was 125 L / (g·cm), and ε(420) / ε(400) was 0.0153.

[0388] Then, 1 1H-NMR analysis was performed, and the following peaks were observed, confirming the formation of compound UVA-01.

[0389] 1 1H-NMR (CDCl3) δ: 1.21 (t, 3H), 2.10 (quIn. 2H), 2.98 - 3.04 (m, 5H), 3.54 - 3.72 (m, 6H), 4.31 (t, 2H), 5.53 (d, 2H), 7.93 (d, 2H)

[0390]

Chemical Formula 12

[0391]

[0392] (Formation of the surface treatment layer)

[0393] On a triacetyl cellulose film with a thickness of 25 μm, the above surface treatment layer composition was coated using a wire bar so that the film thickness after curing became 8 μm, forming a coating film. For the formed coating film, dry air at 70 °C was circulated at a flow rate of 0.5 m / s for 30 seconds, thereby evaporating the solvent. In a nitrogen atmosphere (oxygen concentration of 200 ppm or less), ultraviolet rays were irradiated so that the cumulative light amount became 200 mJ / cm 2 to cure it, thereby forming a surface treatment layer (NUV-HC layer). The transmittance Tr(450) of light with a wavelength of 450 nm of the surface treatment layer (NUV-HC layer) was 90%, the transmittance Tr(420) of light with a wavelength of 420 nm was 50%, and the transmittance Tr(400) at a wavelength of 400 nm was 0%. Thus, a transparent protective film 1 as a triacetyl cellulose film having an NUV-HC layer was obtained. The thickness of the transparent protective film 1 was 33 μm. The transmittance at 380 nm of the transparent protective film 1 was 0%.

[0394] (8) Fabrication of an optical laminate

[0395] The retardation film, polarizer 1, and transparent protective film 1 fabricated above were laminated in sequence. In a state where the polarizer 1 was in contact with the substrate film side of the retardation film and the TAC film of the transparent protective film 1 was in contact with the side of the polarizer 1 opposite to the retardation film, the above aqueous adhesive was injected between the respective layers and laminated using a nip roll so that the angle formed by the absorption axis of the polarizer 1 and the slow axis of the liquid crystal cured film in the retardation film was 45°. Then, it was dried at 60 °C for 2 minutes. Next, the adhesive layer exposed by peeling off one separator from the adhesive sheet fabricated above was laminated on the liquid crystal cured film of the retardation film. Thus, an optical laminate composed of separator / adhesive layer / liquid crystal cured film / photo-alignment film / substrate film / adhesive layer / polarizer 1 / adhesive layer / transparent protective film 1 was obtained. It should be noted that the total thickness of the optical laminate shown in Table 1 refers to the thickness after removing the thickness of the separator (the thickness from the adhesive layer to the transparent protective film 1).

[0396] [Example 2]

[0397] In the fabrication of the above polarizer 1, the concentration of the aqueous solution containing iodine and the immersion time of the film in the aqueous solution were adjusted to obtain a polarizer 2 with a visibility correction monomer transmittance Ty of 42.2% and a thickness of 12 μm. The polarizer 1 was changed to the polarizer 2, and otherwise, the same operations as in Example 1 were performed to obtain the optical laminate of Example 2.

[0398] [Example 3]

[0399] The transparent protective film 1 was changed to the following transparent protective film 2, and the same operations as in Example 1 were carried out except for this, to obtain the optical laminate of Example 3. That is, as the transparent protective film 2, a film (manufactured by Nippon Paper Industries Co., Ltd., thickness 28 μm, 380 nm transmittance 3.5%) in which a hard coat layer (hereinafter sometimes referred to as "HC layer") with a thickness of 3 μm was formed on a stretched film made of a norbornene-based resin with a thickness of 25 μm was used. The HC layer was formed by the following method.

[0400] (Preparation of surface treatment layer composition)

[0401] As the surface treatment layer composition, 20 parts of EBECRYL 4858 (manufactured by DAICEL-ALLNEX Co., Ltd.), 0.21 part of Irgacure-184 (manufactured by BASF Japan Co., Ltd.), 26 parts of cyclopentanone (manufactured by Kanto Chemical Co., Inc.), and 24 parts of N-methyl-2-pyrrolidone (manufactured by Kanto Chemical Co., Inc.) were mixed and stirred at room temperature for 2 hours, thereby obtaining a homogeneous solution.

[0402] (Formation of surface treatment layer)

[0403] On a stretched film made of a norbornene-based resin with a thickness of 25 μm, the above surface treatment layer composition was coated using a wire bar so that the film thickness after curing became 3 μm to form a coating film. For the formed coating film, dry air at 70 °C was passed at a flow rate of 0.5 m / s for 30 seconds to evaporate the solvent, and ultraviolet rays were irradiated in a nitrogen atmosphere (oxygen concentration 200 ppm or less) so that the cumulative light amount became 200 mJ / cm 2 to cure it, thereby forming a surface treatment layer. The transmittance Tr(450) of the surface treatment layer for light with a wavelength of 450 nm was 100%, the transmittance Tr(420) for light with a wavelength of 420 nm was 100%, and the transmittance Tr(400) for light with a wavelength of 400 nm was 100%.

[0404] [Example 4]

[0405] The transparent protective film 1 was changed to the following transparent protective film 3, and the same operations as in Example 1 were carried out except for this, to obtain the optical laminate of Example 4. That is, as the transparent protective film 3, a hard-coated cyclic olefin-based resin film (thickness 14 μm, 380 nm transmittance 5.3%) in which a hard coat layer (HC layer) with a thickness of 1 μm was formed on one side of a cyclic olefin-based resin film (COP film) with a thickness of 13 μm was used. Regarding the HC layer of the transparent protective film 3, except for changing the thickness, it was formed by the same method as the HC layer of the transparent protective film 2.

[0406] [Example 5]

[0407] The base film in the retardation film was changed to the following base film, and otherwise, the operation was the same as in Example 1 to obtain the optical laminate of Example 5. That is, as the base film, a base film obtained by subjecting a triacetyl cellulose film (manufactured by KONICA MINOLTA, thickness 20 μm) to one treatment under the conditions of an output power of 0.3 kW and a treatment speed of 3 m / minute using a corona treatment device (manufactured by Kasuga Electric Co., Ltd., trade name: AGF-B10) was used. The transmittance of the base film at 380 nm was 91%, and the moisture permeability was 1200 g / m 2 ·24 hr.

[0408] [Example 6]

[0409] The base film in the retardation film was changed to the following base film, and otherwise, the operation was the same as in Example 1 to obtain the optical laminate of Example 6. That is, as the base film, a base film obtained by subjecting a triacetyl cellulose film (manufactured by Fujifilm Corporation, trade name: FUJITAC TG60UL, thickness 60 μm) to one treatment under the conditions of an output power of 0.3 kW and a treatment speed of 3 m / minute using a corona treatment device (manufactured by Kasuga Electric Co., Ltd., trade name: AGF-B10) was used. The transmittance of the base film at 380 nm was 91%, and the moisture permeability was 500 g / m 2 ·24 hr.

[0410] [Example 7]

[0411] In the production of the above polarizer 1, the thickness of the raw material film was changed to 60 μm, and the concentration of the iodine-containing aqueous solution and the immersion time of the film in the aqueous solution were adjusted to obtain a polarizer 3 with a visible light corrected monomer transmittance Ty of 42.2% and a thickness of 20 μm. Except for changing the transparent protective film 1 to the following transparent protective film 4 and changing the polarizer 1 to the polarizer 3, the operation was the same as in Example 1 to obtain the optical laminate of Example 7. That is, as the transparent protective film 4, a triacetyl cellulose (TAC) film (manufactured by KONICA MINOLTA, thickness 80 μm, transmittance at 380 nm 1.6%) was used.

[0412] [Example 8]

[0413] The transparent protective film 1 was changed to the following transparent protective film 5, and the thickness of the liquid crystal cured film in the retardation film was changed to 4.0 μm. Otherwise, the operation was the same as in Example 2 to obtain the optical laminate of Example 8. That is, as the transparent protective film 5, a triacetyl cellulose (TAC) film (manufactured by KONICA MINOLTA, thickness 40 μm, transmittance at 380 nm 8.0%) was used. In addition, in the extraction liquid chromatography measurement of the liquid crystal cured film, (S / M) / (ST / M T The value of ( / M) is 5.5.

[0414] [Comparative Example 1]

[0415] In the production of the retardation film, ultraviolet irradiation of the coating film containing the polymerizable liquid crystal compound was performed only from the surface on the coating film side of the laminate composed of the substrate film / photo-alignment film / coating film, and not from the surface on the substrate film side. Otherwise, the operation was the same as in Example 4, and the optical laminate of Comparative Example 1 was obtained. In the extraction liquid chromatography measurement of the liquid crystal cured film, the value of (S / M) / (S T / M T The value of ( / M) is 6.8.

[0416] [Comparative Example 2]

[0417] In the production of the retardation film, ultraviolet irradiation of the coating film containing the polymerizable liquid crystal compound was performed only from the surface on the coating film side of the laminate composed of the substrate film / photo-alignment film / coating film, and not from the surface on the substrate film side. Also, the thickness of the liquid crystal cured film in the retardation film was changed to 2.7 μm. Otherwise, the operation was the same as in Example 8, and the optical laminate of Comparative Example 2 was obtained. In the extraction liquid chromatography measurement of the liquid crystal cured film, the value of (S / M) / (S T / M T The value of ( / M) is 6.8.

[0418] [Evaluation]

[0419] The following evaluations were performed on the optical laminates produced in the examples and comparative examples. The evaluation results are shown in Table 1.

[0420] <Heat resistance>

[0421] The surface on the adhesive layer side of the optical laminate was bonded to an alkali-free glass (manufactured by Corning, product number: EAGLE XG (registered trademark)) having a size of 40 mm × 40 mm and a thickness of 0.7 mm to produce an evaluation sample. The evaluation sample was subjected to a heat resistance test of being stored for 250 hours under dry conditions at a temperature of 85°C, and the change in the in-plane retardation (Re(550)) before and after the test was measured using a retardation measurement device (manufactured by Oji Scientific Instruments Co., Ltd., trade name: KOBRA-WPR). Based on the measurement results, the evaluation was performed according to the following criteria.

[0422] A: The change in the in-plane retardation is less than ±4 nm

[0423] B: The change in the in-plane retardation is 4 nm or more and less than ±6 nm

[0424] C: The change in the in-plane retardation is 6 nm or more

[0425] <Light resistance>

[0426] Attach the surface on the adhesive layer side of the optical laminate to an alkali-free glass (manufactured by Corning Inc., product number: EAGLE XG (registered trademark)) with a size of 40 mm × 40 mm and a thickness of 0.7 mm to produce a sample for evaluation. Place this evaluation sample in a sunshine weather meter (manufactured by Suga Test Instruments Co., Ltd.) under the conditions of a temperature of 63°C and a relative humidity of 50% RH for 375 hours to conduct a light resistance test. After the test, measure the reflection color tone (a * , b * ) with a spectrocolorimeter (manufactured by KONICA MINOLTA INC., product name: CM-2600d), and calculate a * b * according to the following formula, and calculate the change in a * b * before and after the test. The reflection color tone is the value when the light source is D65, and the measurement is carried out using the SCI method (including regular reflection). In addition, during the measurement, place the evaluation sample on the aluminum reflector with the alkali-free glass side corresponding to the aluminum reflector, and in the state of forming a layer structure of aluminum reflector / air / evaluation sample, make light enter from the evaluation sample side for measurement. Based on the following criteria, evaluate according to the measurement results.

[0427] a * b * = 〔(a * ) 2 + (b * ) 2 〕 1 / 2

[0428] A: The change in a * b * is less than 0.5

[0429] B: The change in a * b * is 0.5 or more and less than 1.0

[0430] C: The change in a * b * is 1.0 or more and less than 1.5

[0431] D: The change in a * b * is 1.5 or more

[0432] <Reflection color tone>

[0433] The surface on the adhesive layer side of the optical laminate was bonded to an alkali-free glass (manufactured by Corning Inc., product number: EAGLE XG (registered trademark)) with a size of 40 mm × 40 mm and a thickness of 0.7 mm to produce an evaluation sample. For this evaluation sample, the reflection color tone (a * , b * ) was measured using a spectrocolorimeter (manufactured by KONICA MINOLTA INC., trade name: CM-2600d), and a * b * was calculated according to the following formula. The reflection color tone is the value when the light source is D65, and the measurement is performed using the SCI method (including regular reflection). In addition, during the measurement, the evaluation sample was placed on an aluminum reflector with the alkali-free glass side corresponding to the aluminum reflector, and in a state where the layer structure of aluminum reflector / air / evaluation sample was formed, light was incident from the evaluation sample side for measurement. Based on the measurement results, evaluation was carried out according to the following criteria.

[0434] a * b * = [(a * ) 2 + (b * ) 2 1 / 2

[0435] A: a * b * is less than 4.0

[0436] B: a * b * is 4.0 or more

[0437]

Table 1

[0438]

[0439] Explanation of reference numerals

[0440] 1... Adhesive layer, 2... Liquid crystal cured film, 3... Alignment film, 4... Substrate film, 5... Adhesive layer, 6... Polarizer, 7... Adhesive layer, 8... Protective film, 10... Phase difference film, 100... Optical laminate.​

Claims

1. An optical laminate, which comprises a protective film, a polarizing plate, a substrate film and a liquid crystal cured film in this order, The thickness of the liquid crystal cured film is 2.5 μm or more. The extraction liquid chromatography measurement result of the liquid crystal cured film satisfies the following formula (A): (S / M) / (S T / M T )≤6.4 …(A) S: the sum of the peak areas of each liquid crystal monomer; M: extraction solution concentration; S T : Peak area of ​​toluene; M T : Toluene solution concentration.

2. The optical layered body according to claim 1, wherein: The 380nm transmittance of the protective film is less than 10%.

3. The optical layered body according to claim 1, wherein: The 380 nm transmittance of the substrate film is greater than 50%.

4. The optical laminate according to claim 1, wherein: The moisture permeability of the substrate film is 50 g / m 2 ·More than 24hr.

5. The optical layered body according to claim 1, wherein: The thickness of the substrate film is 30 μm or more.

6. The optical layered body according to claim 1, wherein: The visibility correction single body transmittance Ty of the polarizing plate is greater than or equal to 40%.

7. The optical layered body according to claim 1, wherein: The total thickness of the optical laminate is 150 μm or less, The polarizer has a thickness of 15 μm or less.

8. The optical layered body according to claim 1, wherein: The thickness of the liquid crystal cured film is 3.5 μm or less.

9. A method for producing a liquid crystal cured film, comprising: a step of forming a coating film on a substrate film using a polymerizable liquid crystal composition containing a polymerizable liquid crystal compound; and a step of irradiating the coating film with active energy rays from both sides thereof to cure the coating film, thereby forming a liquid crystal cured film having a thickness of 2.5 μm or more and satisfying the following formula (A) as a result of extraction liquid chromatography measurement, (S / M) / (S T / M T )≤6.4 …(A) S: the sum of the peak areas of each liquid crystal monomer; M: extraction solution concentration; S T : Peak area of ​​toluene; M T : Toluene solution concentration.

10. The method for producing a liquid crystal cured film according to claim 9, wherein: The 380 nm transmittance of the substrate film is greater than 50%.

11. The method for producing a liquid crystal cured film according to claim 9, wherein: The moisture permeability of the substrate film is 50 g / m 2 ·More than 24hr.

12. The method for producing a liquid crystal cured film according to claim 9, wherein: The thickness of the substrate film is 30 μm or more.

13. The method for producing a liquid crystal cured film according to claim 9, wherein: The thickness of the liquid crystal cured film is 3.5 μm or less.

14. A method for producing an optical laminate, which comprises a protective film, a polarizing plate, a substrate film and a liquid crystal cured film in this order, The said manufacturing method has the process of manufacturing the said liquid crystal cured film by the manufacturing method of the liquid crystal cured film in any one of Claims 9-13.

15. The method for producing an optical layered body according to claim 14, wherein: The 380nm transmittance of the protective film is less than 10%.

16. The method for producing an optical layered body according to claim 14, wherein: The visibility correction single body transmittance Ty of the polarizing plate is greater than or equal to 40%.

17. The method for producing an optical layered body according to claim 14, wherein: The total thickness of the optical laminate is 150 μm or less, The polarizer has a thickness of 15 μm or less.

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