Functional film, polarizing plate and image display device

Abstract

To provide a functional film that can be produced with available constituents, in which a wavelength dispersion property matches or approximates an ideal curve of a reverse wavelength dispersion property, and also to provide a polarizer and a picture display unit.SOLUTION: A functional film at least includes two or more functional layers. In the functional layer (1), if a refractive index in an in-plane slow axis direction is nx, a refractive index in an in-plane direction orthogonal to the nx is ny, and a refractive index in a depthwise direction of the functional layer (1) is nz, a relation nx>ny is satisfied. The functional layer (2) includes one kind of, or two or more kinds of dichroic infrared absorption pigments or polymers thereof. An absorption axis direction of at least the dichroic infrared absorption pigment to incident light of 750nm is substantially orthogonal to the direction of nx of the functional layer (1).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a functional film, a polarizing plate, and an image display device. [Background technology]

[0002] Liquid crystal display elements and organic electroluminescence (EL) elements are used in various electronic devices to visually transmit information. In liquid crystal display elements such as IPS mode, functional films are used to improve the viewing angle characteristics resulting from the alignment state of liquid crystal molecules, and in organic EL elements, functional films are used to reduce the reflection of external light caused by metal electrodes.

[0003] For example, in a liquid crystal display device such as an IPS mode, an optical film having a retardation layer combining a positive A layer and a positive C layer has been proposed in order to increase contrast when viewed from an oblique direction. In addition, in organic EL devices and the like, a circular polarizer, which is a combination of a λ / 4 phase difference film and a linear polarizer, is used to prevent reflection of external light.

[0004] Thus, functional films with retardation are indispensable for optical elements. However, general-purpose functional films have a wavelength dependency of retardation (hereinafter also called positive wavelength dispersion) in which the retardation measured at long wavelengths in the visible light region is smaller than the retardation measured at short wavelengths, so that the retardation curve deviates from the ideal retardation curve, and there is a problem that the effect of optical compensation varies depending on the wavelength of the incident light.

[0005] To improve this, methods have been proposed, such as using a functional film that has wavelength dependence of retardation (hereinafter also referred to as inverse wavelength dispersion) such that the retardation at long wavelengths is larger than the retardation at short wavelengths (Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] WO2014 / 010325 issue [Patent Document 2] WO2019 / 044859 issue Summary of the Invention [Problem to be solved by the invention]

[0007] In the invention described in Patent Document 1, the reverse wavelength dispersion is insufficient, and the dispersion characteristics of the functional film deviate from the ideal curve of the reverse wavelength dispersion, and therefore improvements were required. To remedy this, Patent Document 2 has developed a material that combines infrared absorbing dyes with specific structures; however, the properties of the material are insufficient, and further improvements have been required, such as the need for a dichroic infrared absorbing dye that is difficult to obtain and has a complex manufacturing process to solve the problem with a single layer of functional film.

[0008] An object of the present invention is to provide a functional film, a polarizing plate, and an image display device that can be produced using readily available components and whose wavelength dispersion characteristics match or approximate the ideal curve of reverse wavelength dispersion. [Means for solving the problem]

[0009] As a result of extensive research, the present inventors have found that the above-mentioned problems can be solved by providing a functional film described below.

[0010] The present invention provides the following functional film, polarizing plate, and image display device. [1] A functional film including at least two functional layers, the refractive index of the functional layer (1) in the slow axis direction in the plane being nx, Slow axis direction The functional layer (2) contains one or more dichroic infrared absorbing dyes or polymers thereof, and the absorption axis direction of at least the dichroic infrared absorbing dye with respect to incident light of 750 nm is aligned with that of the functional layer (1). Slow axis A functional film that is approximately perpendicular to the direction. [2] The functional film according to [1], wherein the functional layer (1) satisfies nx>ny≒nz. [3] The functional film according to [1], wherein the functional layer (1) satisfies nx≒nz>ny. [4] The functional layer (2) is a polymer of a polymerizable composition containing a polymerizable liquid crystal compound, and the long axis direction of the mesogen of the polymerizable liquid crystal compound is the same as that of the functional layer (1). Orthogonal to the slow axis direction The functional film according to any one of [1] to [3], wherein the dichroic dye exhibits positive dichroism and is oriented along the major axis direction of the mesogen of the polymerizable liquid crystal, the direction being approximately parallel to the major axis direction. [5] The functional layer (1) Thickness direction The absorbance (I 750 ) and absorbance at 630 nm wavelength (I 630 ) ratio (I 750 / I 630 ) is 3 or more. [6] The functional film according to any one of [1] to [5], further comprising one or more dichroic ultraviolet absorbing dyes or polymers thereof in at least one of the functional layers. [7] The in-plane retardation (Re) of a functional film for light with a wavelength of 450 nm 450 ), and the in-plane retardation (Re 550 ) and the in-plane retardation (Re 650 ) is Re 450 / Re 550 <1.0, Re 650 / Re 550 The functional film according to any one of [1] to [6], wherein the relationship of [R]=0.05% or more and [R]=0.05% or more. [8] The functional film according to any one of [1] to [7], further comprising a functional layer (3), the functional layer (3) being a functional layer of a positive C plate. [9] The functional film according to any one of [1] to [8], further comprising a functional layer (3), the functional layer (3) comprising a linear polarizing plate.

[10] An image display device having the functional film according to any one of [1] to [9] on a light exit surface of a display element.

[11] The image display device according to

[10] , wherein the image display device is an organic electroluminescence display device and has a metal electrode in an emitting layer. Effect of the Invention

[0011] The functional film, polarizing plate and image display device of the present invention exhibit excellent reverse wavelength dispersion properties without using a dichroic infrared absorbing dye which is difficult to obtain. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic diagram showing a method for improving reverse wavelength dispersion by a dichroic infrared absorbing dye. [Diagram 2] FIG. 1 is a conceptual diagram of a positive dichroic infrared absorbing dye. [Diagram 3] Conceptual diagram of improving wavelength dispersion with one type of dichroic infrared absorbing dye or its polymer [Figure 4] Conceptual diagram of improving wavelength dispersion with two types of dichroic infrared absorbing dyes or their polymers [Diagram 5] Schematic diagram of form 1 [Figure 6] FIG. 1 is a schematic diagram showing a method for improving reverse wavelength dispersion using a dichroic ultraviolet absorbing dye. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described. [Functional Film] The functional film of the present invention may be composed of two functional layers, or may include three or more functional layers. When the functional film has two functional layers, it includes one functional layer (1) and at least one functional layer (2) containing one or more dichroic infrared absorbing dyes or polymers thereof. The order of lamination of the functional layers (1) and (2) is not particularly limited. When a plurality of functional layers are laminated, they may be bonded via an adhesive layer, or a two-layer plastic film laminate may be formed by applying a polymerizable compound to at least one plastic film and then polymerizing the compound by heat or energy rays.

[0014] Examples of the layer structure of the functional film of the present invention are shown below, but the present invention is not limited to these.

[0015] [Table 1]

[0016] In the table, Pos A represents the functional layers of a positive A plate, and Neg A represents the functional layers of a negative A plate. Configuration (1) exhibits the characteristics of a positive A plate with reverse wavelength dispersion by combining functional layer (1), which is a positive A plate that does not contain a dichroic infrared absorbing pigment, with functional layer (2), which is a positive A plate that contains a dichroic infrared absorbing pigment that exhibits positive dichroism, and configuration (2) exhibits the characteristics of a negative A plate with reverse wavelength dispersion by combining functional layer (1), which is a negative A plate that does not contain a dichroic infrared absorbing pigment, with functional layer (2), which is a positive A plate that contains a dichroic infrared absorbing pigment that exhibits positive dichroism.

[0017] In Fig. 1, (A) is an ideal curve of the in-plane retardation due to the wavelength of a plastic film exhibiting reverse wavelength dispersion, but the in-plane retardation increases toward the long wavelength region. In contrast, (B) is a schematic representation of the wavelength dispersion of a conventional plastic film, and the deviation from the ideal curve is particularly large in the long wavelength region. In the present invention, a dichroic infrared absorbing dye is used to improve the in-plane retardation in the long wavelength region, approaching the ideal curve and improving the reverse wavelength dispersion.

[0018] The functional film with reverse wavelength dispersion has an in-plane retardation (Re 450 ), and the in-plane retardation (Re 550 ) and the in-plane retardation (Re 650 ) is Re 450 / Re 550 <1.0 and Re 650 / Re 550 >1.0. This indicates that the retardation is large over the entire visible light range, especially in the long wavelength range (650 nm). 450 / Re 550 is more preferably 0.98 or less, further preferably 0.96 or less, and even more preferably 0.95 or less. The smaller this value, the greater the reverse wavelength dispersion, which is preferable, but from the viewpoint of the compatibility of the compound used with other compounds and the liquid crystallinity described later, it is preferably 0.70 or more, more preferably 0.72 or more, and even more preferably 0.74 or more. 650 / Re 550 is more preferably 1.10 or more, further preferably 1.12 or more, and even more preferably 1.14 or more. The larger this value is, the greater the reverse wavelength dispersion is, and therefore, preferable, but from the viewpoint of the compatibility of the compound used with other compounds and the liquid crystallinity described later, it is preferably 1.30 or less, more preferably 1.28 or less, and even more preferably 1.26 or less.

[0019] The in-plane retardation (Re) can be measured, for example, by using a product called "RETS-100" manufactured by Otsuka Electronics Co., Ltd. or a product called "KOBRA-WR" manufactured by Oji Scientific Instruments Co., Ltd. In-plane phase difference (Re)=(nx-ny)×T[nm] (A) When measuring the in-plane retardation (Re) and the like using Otsuka Electronics' product name "RETS-100", it is preferable to prepare for the measurement according to the following procedures (A1) to (A4). (A1) First, turn on the RETS-100 light source and leave it for 60 minutes or more to stabilize it. After that, select the rotating analyzer method and select θ mode (angle direction phase difference measurement and Rth calculation mode). By selecting this θ mode, the stage becomes a tilt rotation stage.

[0020] (A2) Next, enter the following measurement conditions into the RETS-100. [Measurement conditions] Retardation measurement range: Rotating analyzer method Measurement spot diameter: φ5mm Tilt angle range: -40 degrees to +40 degrees in 10 degree increments (however, select 0 degrees for Re measurement) Measurement wavelength range: 400nm~800nm Average refractive index of functional film (for example, in the case of acrylic resin, the average value is 1.55) Thickness: Actual measured value of thickness (record the thickness measured separately using a SEM or optical microscope).

[0021] (A3) Next, background data is obtained without placing a sample in the instrument, in a closed system, and every time the light source is turned on. (A4) Then, the sample is placed on the stage in the device and measured. The in-plane retardation (Re) and thickness direction retardation (Rth) of the functional film can be measured even when the functional film has other layers such as an ultraviolet absorbing layer on it. When the functional film has other layers on it, it is preferable to measure the surface with higher flatness by placing it so that it faces the stage side.

[0022] The functional film with reverse wavelength dispersion of the present invention preferably has a haze according to JIS K7136:2000 of 3.0% or less, more preferably 2.0% or less, and even more preferably 1.0% or less. Furthermore, the functional film with reverse wavelength dispersion of the present invention preferably has a total light transmittance according to JIS K7361-1:1997 of 80% or more, more preferably 85% or more, and even more preferably 90% or more.

[0023] [Functional Layer] The functional layer in the present invention may be a polymer obtained by applying a polymerizable liquid crystal compound to a strongly stretched plastic film, a weakly stretched plastic film, a non-stretched plastic film, or a substrate, or by polymerizing the polymerized liquid crystal compound after the orientation. The functional layers in the present invention are functional layer (1), functional layer (2), and other functional layer (3). The functional film of the present invention has the properties of an A plate that exhibits reverse wavelength dispersion.

[0024] [Functional layer (1)] The functional layer (1) has the properties of an A plate, and has a refractive index in the slow axis direction in the plane of nx and a refractive index in the slow axis direction in the plane of Slow axis direction When the refractive index in the direction perpendicular to the plane of the film is ny and the refractive index in the thickness direction of the functional layer (1) is nz, the relationship nx>ny is satisfied. The functional layer (1) has a slow axis direction in which the in-plane refractive index is greatest, and the refractive index in the slow axis direction is nx.

[0025] nz represents the refractive index in the thickness direction of the functional layer (1), Slow axis direction and Orthogonal to the slow axis direction The refractive index is the direction perpendicular to the direction. In the functional layer (1), nx>ny, but it may be nx>ny≒nz (a so-called positive A plate) or nx≒nz>ny (a so-called negative A plate). It is preferable that nx>ny≒nz in that the functional layer (1) can be used in a wide range of technical fields.

[0026] The functional layer (1) where nx>ny≈nz and the functional layer (1) where nx≈nz>ny may be a general-purpose plastic film, or may be a functional layer using a polymerizable liquid crystal compound. In addition, the functional layer (1) may exhibit positive wavelength dispersion, reverse wavelength dispersion, or flat wavelength dispersion. From the viewpoint of ease of availability, however, those exhibiting positive wavelength dispersion or flat wavelength dispersion are preferred, since general-purpose plastic films can be used, and those exhibiting positive wavelength dispersion are preferred. To manufacture the functional layer (1) using a polymerizable liquid crystal compound, in the case of a plastic film where nx>ny≒nz, the rod-shaped liquid crystal can be oriented horizontally to the substrate in a so-called homogeneous manner and then polymerized while maintaining the oriented state. In the case of a plastic film where nx≒nz>ny, the functional layer (1) can be prepared by aligning the discotic liquid crystal molecules perpendicular to the substrate, or by aligning the helical axis of the rod-shaped polymerizable liquid crystal compound in a direction that is approximately the same as the direction horizontal to the substrate, and then polymerizing the compound.

[0027] In addition, in this specification, "approximately vertical" means that the intended orientation is vertical, but includes slight deviations from vertical due to fluctuations or the like, and specifically means within 90 degrees ±5 degrees, preferably within 90 degrees ±3 degrees, and more preferably within 90 degrees ±1 degree; "approximately horizontal" means that the intended orientation is horizontal, but includes slight deviations from horizontal due to fluctuations or the like, and specifically means within 90 degrees ±5 degrees, preferably within 90 degrees ±3 degrees, and more preferably within 90 degrees ±1 degree.

[0028] As the rod-like liquid crystal, a polymerizable liquid crystal compound having a positive wavelength dispersion and a polymerizable liquid crystal compound having a reverse wavelength dispersion can be used.

[0029] When the functional layer (1) is a stretched plastic film, the thickness is preferably 20 to 200 μm, more preferably 25 to 180 μm, and even more preferably 30 to 150 μm. By making the thickness 20 μm or more, it is possible to easily improve the mechanical strength. Also, by making the thickness 200 μm or less, it is possible to easily meet the requirement for thinning.

[0030] The stretched plastic film is preferably biaxially stretched. When the polymerizable liquid crystal compound is applied to a substrate for production, the thickness is preferably 0.1 to 5 μm, more preferably 0.2 to 4 μm, and even more preferably 0.5 to 3 μm.

[0031] <Stretched plastic film> Examples of resin components constituting the stretched plastic film include polyester, polyamide, polyimide, polyethersulfone, polysulfone, polypropylene, polymethylpentene, polyvinyl chloride, polyvinyl acetal, polyether ketone, polymethyl methacrylate, polycarbonate, polyurethane, and amorphous olefin (Cyclo-Olefin-Polymer: COP), etc. Among these, polyester is preferred because it is easy to improve the mechanical strength, and polycarbonate and amorphous olefin are preferred because it is easy to adjust the wavelength dispersion.

[0032] A stretched plastic film can be obtained by stretching a resin layer. The stretching method can be biaxial stretching such as sequential biaxial stretching and simultaneous biaxial stretching, or uniaxial stretching such as longitudinal uniaxial stretching.

[0033] The biaxially stretched plastic film can be obtained by stretching a resin layer containing the components constituting the plastic film. The stretching method includes biaxial stretching such as sequential biaxial stretching and simultaneous biaxial stretching. Among the biaxially stretched plastic films, a biaxially stretched polyester film is preferable, and a biaxially stretched polyethylene terephthalate film is more preferable.

[0034] <Discotic Liquid Crystal> In the present invention, a discotic liquid crystal compound may be used to form the functional layer (1). Discotic liquid crystal compounds are described in various documents (C. Destrade et al., Mol. Crysr. Liq. Cryst., vol. 71, page 111 (1981); Quarterly Chemistry Review, No. 22, Chemistry of Liquid Crystals, edited by the Chemical Society of Japan, Chapter 5, Chapter 10, Section 2 (1994); B. Kohne et al., Angew. Chem. Soc. Chem. Comm., page 1794 (1985); J. Zhang et al., J. Am. Chem. Soc., vol. 116, page 2655 (1994), etc.). The polymerization of discotic liquid crystal compounds is described in JP-A-8-27284.

[0035] The discotic liquid crystal compound preferably has a polymerizable group so that it can be fixed by polymerization. For example, a structure in which a polymerizable group is bonded as a substituent to the discotic core of the discotic liquid crystal compound is conceivable, but if the polymerizable group is directly bonded to the discotic core, it becomes difficult to maintain the alignment state during the polymerization reaction. Therefore, a structure having a linking group between the discotic core and the polymerizable group is preferred. In other words, the discotic liquid crystal compound having a polymerizable group is preferably a compound represented by the following general formula (D1).

[0036] [ka]

[0037] In the formula, A D1 is D1 represents a 1-valent discotic group; R D1 is a hydrogen atom, a fluorine atom, a chlorine atom, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or -Sp D1 -P D1wherein one or more hydrogen atoms in the alkyl and alkenyl groups may be substituted with fluorine or chlorine atoms, and when there are a plurality of such atoms, they may be the same or different; one or more -CH2- in the alkyl and alkenyl groups may be substituted with -O-, -COO-, -OCO-, -NH-, -CONH-, -NHCO-, -CH=CH- or -C≡C-, and when there are a plurality of such atoms, they may be the same or different; D1 represents a spacer or a single bond, Sp D1 The hydrogen atom in is -Sp D1 -P D1 may be substituted with P D1 represents a polymerizable group; B D1 represents a divalent linking group, while B D1 The hydrogen atom in is -Sp D1 -P D1 may be substituted with A D2 represents a divalent cyclic group, while A D2 The hydrogen atom in is -Sp D1 -P D1 may be substituted with n D1 represents a natural number from 1 to 20, but A D1 valence of n D2 represents a natural number from 0 to 5, but R D1 , Sp D1 , P D1 , B D1 , A D2 and / or n D2 When multiple are present, they may be the same or different. A D1 is represented by the general formula (A D1 -1)~(A D1 A discotic group represented by the general formula (A D1 -1), (A D1 -2), (A D1 -8) and (A D1 A discotic group represented by the formula (12) is more preferred.

[0038] [ka]

[0039] [ka]

[0040] [ka]

[0041] [ka]

[0042] [ka]

[0043] (Wherein, * represents B D1 Met represents a divalent metal, and the hydrogen atoms in the formula are R D1 may be substituted with R D1 is R D1 is a hydrogen atom, a fluorine atom, a chlorine atom, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, or -Sp D1 -P D1 is preferred, and a hydrogen atom, a fluorine atom, a chlorine atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or -Sp D1 -P D1 are more preferable, which may be linear or branched, and one or more -CH2- groups in the alkyl and alkenyl groups may be substituted by -O-, -COO- or -OCO-. Sp D1 is preferably an alkylene group having 1 to 20 carbon atoms or a single bond, and more preferably an alkylene group having 2 to 8 carbon atoms or a single bond. P D1 is represented by the general formula (P D1 -1)~(P D1 -9), and the polymerizable group represented by the general formula (P D1 The polymerizable group represented by the formula (1) is more preferred.

[0044] [ka]

[0045] (Wherein, * denotes Sp D1 is bonded to R p1 represents a hydrogen atom or a methyl group. B D1 is preferably a single bond, -O-, -COO-, -OCO-, -NH-, -CONH-, -NHCO-, -CH=CH-, -C≡C-, -CH=CH-COO- or -OCO-CH=CH-, and more preferably a single bond, -O-, -COO-, -OCO-, -CH=CH-, -C≡C-, -CH=CH-COO- or -OCO-CH=CH-. A D2 is preferably a divalent group having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocycle which may have a substituent, or a divalent group having an aliphatic hydrocarbon ring which may have a substituent, and is more preferably the following groups (a), (b), and (c). (a) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may be replaced by -O-), (b) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=); and (c) a biphenyl-4,4'-diyl group, a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (provided that one -CH= or two or more non-adjacent -CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by -N=),

[0046] wherein the hydrogen atoms in the groups (a), (b) and (c) each independently represent an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyloxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, a cyano group, a fluorine atom, a chlorine atom or -Sp D1 -P D1 may be substituted with n D1 is preferably 2 to 18, and more preferably 4, 6, 8 or 12. n D2 is preferably 1 to 4, and more preferably 1 or 2. The molecule contains the general formula (P D1 It is preferable that the copolymer has 1 to 20 polymerizable groups represented by -1), and more preferably has 4, 6, 8 or 12 polymerizable groups.

[0047] The discotic nematic liquid crystal phase-solid phase transition temperature of the liquid crystal compound is preferably 30 to 300°C, and more preferably 30 to 170°C.

[0048] <Polymerizable liquid crystal compound with positive wavelength dispersion> In the present invention, one or more kinds of positive wavelength dispersion polymerizable liquid crystal compounds may be used as rod-like liquid crystals to form the functional layer (1). It is more preferable to fix the positive wavelength dispersion polymerizable liquid crystal compound in an aligned state by polymerization. The liquid crystal compound preferably has a partial structure capable of undergoing polymerization or crosslinking reaction by actinic rays, electron beams, heat, etc., and more preferably has a polymerizable group. The number of polymerizable groups in the molecule is preferably from 1 to 6, and more preferably from 1 to 3. As the polymerizable liquid crystal compound having positive wavelength dispersion, a compound represented by general formula (L1) is preferable.

[0049] [ka]

[0050] In the formula, R L1 and R L2 each independently represents R in general formula (D1). D1 It has the same meaning as R L1 and R L2 -Sp L1 -P L1 However, Sp L1 is Sp in general formula (D1). D1 It has the same meaning as P L1 is P in general formula (D1). D1 It means the same thing as A L1 and A L2 are each preferably a divalent group having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocycle which may have a substituent, or a divalent group having an aliphatic hydrocarbon ring which may have a substituent, and are more preferably the following groups (a), (b), and (c). (a) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may be replaced by -O-), (b) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=); and (c) a biphenyl-4,4'-diyl group, a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (provided that one -CH= or two or more non-adjacent -CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by -N=),

[0051] wherein the hydrogen atoms in the groups (a), (b) and (c) each independently represent an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyloxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, a cyano group, a fluorine atom, a chlorine atom or -Sp D1 -P D1 may be substituted with B L1 represents B in general formula (D1). D1 It means the same as n L1 represents a natural number of 1 to 4, with 2, 3 or 4 being preferred.

[0052] The compound represented by general formula (L1) is preferably a compound represented by general formulas (L-1) to (L-4), but is not limited thereto.

[0053] [ka]

[0054] (In the formula, P L11 and P L21 are each independently P L1 and R L21 represents an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms; R L3 represents a fluorine atom, a chlorine atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms, and the phenylene group and the naphthalene-2,6-diyl group in the formula are R L3 may be substituted by n L3 and n L7 Each independently represents a natural number from 2 to 8, and n L4 and n L6 Each independently represents 0 or 1; n L5 represents 1 or 2.)

[0055] Further, polymerizable liquid crystal compounds with positive wavelength dispersion are described in Makromol. Chem., Vol. 190, p. 2255 (1989), Makromol. Chem., Vol. 192, p. 59 (1991), Advanced Compounds described in, for example, Materials, Vol. 5, p. 107 (1993), U.S. Pat. Nos. 4,683,327, 5,622,648, and 5,770,107, International Publication WO 95 / 22586, 95 / 24455, 97 / 00600, 98 / 23580, and 98 / 52905, JP-A 1-272551, 6-16616, 7-110469, 11-80081, and 2001-328973 can be used.

[0056] <Liquid crystal compound exhibiting reverse wavelength dispersion> In the present invention, one or more kinds of polymerizable liquid crystal compounds having reverse wavelength dispersion may be used as the rod-like liquid crystal. As the polymerizable liquid crystal compound having reverse wavelength dispersion, a compound represented by the general formula (R1) is preferable.

[0057] [ka]

[0058] In the formula, R R1 and R R2 each independently represents R in general formula (D1). D1 It has the same meaning as R R1 P R1 -Sp R1 - may be R R2 -Sp R2 -P R2 However, Sp R1 and Sp R2 Each independently represents Sp in general formula (D1). D1 It has the same meaning as P R1 and P R2 each independently represents P in general formula (D1). D1 It has the same meaning as A R2 , A R3 , A R4 and AR5 are each preferably independently a divalent group having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocycle which may have a substituent, or a divalent group having an aliphatic hydrocarbon ring which may have a substituent, and are preferably the following groups (a), (b), and (c). (a) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may be replaced by -O-), (b) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=); and (c) a biphenyl-4,4'-diyl group, a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (provided that one -CH= or two or more non-adjacent -CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by -N=),

[0059] wherein the hydrogen atoms in the groups (a), (b) and (c) each independently represent an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyloxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, a cyano group, a fluorine atom, a chlorine atom or -Sp D1 -P D1 may be substituted with A R1 represents a substituent represented by general formulae (AR1) to (AR7),

[0060] [ka]

[0061] (In the formula, ★ represents B R1 Or B R2Combined with ★★ and B R1 Combined with, ★★★ and D R1 The hydrogen atoms in the formula are bonded to R R1 may be substituted by D R1 represents a substituent represented by general formula (DR1),

[0062] [ka] (In the formula, G R1 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and the alkyl group is unsubstituted or has one or more R R1 may be replaced by J R1 -O-, -S-, -COO-, -OCO-, -OCO-O-, -NG R2 -,-N=CG R2 -,-CO-NG R2 -,-OCO-NG R2 -or-NG R2 - represents G R2 is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, a cycloalkenyl group having 3 to 12 carbon atoms, an organic group having 2 to 30 carbon atoms and an aromatic cyclic group having 6 to 18 carbon atoms (any -CH= in the aromatic hydrocarbon group may be replaced with -N=), or -Sp R2 -P R2 The alkyl group, the cycloalkyl group, the cycloalkenyl group, and the aromatic cyclic group each are unsubstituted or each have one or more R R1the alkyl group may be substituted by the cycloalkyl group or cycloalkenyl group, one -CH2- or two or more non-adjacent -CH2- in the alkyl group may be each independently replaced by -O-, -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -SO2-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-, and one -CH2- or two or more non-adjacent -CH2- in the cycloalkyl group or cycloalkenyl group may each independently be replaced by -O-, -CO-, -COO-, -OCO- or -O-CO-O-; R1 represents an organic group having 2 to 30 carbon atoms and having an aromatic hydrocarbon group, any carbon atom of the aromatic hydrocarbon group may be substituted with a heteroatom, and the aromatic hydrocarbon group is unsubstituted or has one or more R R1 may be substituted by, but K R1 represents a substituent represented by the general formula (KR1) to (KR3),

[0063] [ka]

[0064] (In the formula, ★ indicates J R1 ) B R1 , B R2 , B R3 and B. R4 each independently represents B in general formula (D1). D1 It means the same as n R1 represents a natural number from 1 to 4, preferably 2, 3, or 4; n R2 and n R3 Each independently represents a natural number of 0 to 4, preferably 0, 1 or 2, but R R1 , R R2 , P R1 , P R2 Sp R1 , SpR2 , A R2 , A R3 , A R4 , A R5 , D R1 , G R1 and / or G R2 may be the same or different.

[0065] In addition, as liquid crystal compounds exhibiting reverse wavelength dispersion, compounds described in each of Patent Publications such as JP-A-2007-002210, JP-A-2010-031223, JP-A-2013-509458, WO2014 / 010325, JP-A-2010-84032, and JP-A-2016-166344 may be used.

[0066] <Polymerization initiator> The aligned liquid crystal compound is fixed while maintaining the aligned state. The fixing is preferably performed by using a polymerization reaction, which includes a thermal polymerization reaction using a thermal polymerization initiator and a photopolymerization reaction using a photopolymerization initiator. Among these, a photopolymerization reaction is preferable. Examples of the photopolymerization initiator include α-carbonyl compounds (see U.S. Pat. Nos. 2,367,661 and 2,367,670), acyloin ethers (see U.S. Pat. No. 2,448,828), α-hydrocarbon substituted aromatic acyloin compounds (see U.S. Pat. No. 2,722,512), polynuclear quinone compounds (see U.S. Pat. Nos. 3,046,127 and 2,951,758), combinations of triaryl imidazole dimers and p-aminophenyl ketones (see U.S. Pat. No. 3,549,367), acridine and phenazine compounds (see JP-A-60-105,667 and U.S. Pat. No. 4,239,850), and oxadiazole compounds (see U.S. Pat. No. 4,212,970).

[0067] The amount of the polymerization initiator used is preferably from 0.01 to 20% by mass, and more preferably from 0.5 to 5% by mass, based on the total solid content of the composition for forming a retardation layer. The light irradiation for polymerizing the liquid crystal compound is preferably performed using ultraviolet light. The irradiation energy is preferably 20 mJ / cm. 2 ~2000mJ / cm2 , more preferably 100 to 1000 mJ / cm 2 In order to promote the photopolymerization reaction, the light irradiation may be carried out under heating conditions.

[0068] <Surfactant> The retardation layer forming composition preferably contains a surfactant. Among the surfactants, it is preferable to select and use one or more selected from a fluorine-based surfactant having a polymerizable group and a silicon-based surfactant having a polymerizable group. The content of the surfactant is preferably from 0.01 to 2.0% by mass, and more preferably from 0.1 to 1.0% by mass, based on the total solid content of the composition for forming a retardation layer.

[0069] <Solvent> The composition for forming the retardation layer usually contains a solvent. Examples of the solvent include ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, etc.), ethers (dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons (hexane, etc.), alicyclic hydrocarbons (cyclohexane, etc.), aromatic hydrocarbons (toluene, xylene, etc.), halogenated carbons (dichloromethane, dichloroethane, etc.), esters (methyl acetate, ethyl acetate, butyl acetate, etc.), alcohols (butanol, cyclohexanol, etc.), cellosolves (methyl cellosolve, ethyl cellosolve, etc.), cellosolve acetates, sulfoxides (dimethyl sulfoxide, etc.), amides (dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, etc.), and mixtures of these may also be used.

[0070] The retardation layer can be formed, for example, by applying, drying, and curing a composition for forming a retardation layer. The composition for forming a retardation layer is preferably applied onto an alignment film.

[0071] <Other additives> In the present invention, the composition for forming the retardation layer may contain, in addition to the above components, an optically active compound, a plasticizer, a polymerizable monomer, etc. It is preferable that these components are compatible with the liquid crystal compound and do not inhibit the alignment.

[0072] <Optically active compounds> As the optically active compound, the compounds represented by the general formulae (Ch1) to (Ch4) are preferable.

[0073] [ka]

[0074] (In the formula, R Ch11 , R Ch12 , R Ch13 , R Ch21 , R Ch22 , R Ch31 , R Ch32 and R Ch41 each independently represents R in general formula (D1). D1 It has the same meaning as A Ch11 , A Ch21 , A Ch22 , A Ch31 , A Ch32 and A Ch41 each independently represents A in general formula (D1). D1 It has the same meaning as B Ch11 , B Ch21 , B Ch22 , B Ch31 , B Ch32 and B. Ch41 each independently represents B in general formula (D1). D1 It means the same as n Ch11 , n Ch21 , n Ch22 , n Ch31 , n Ch32 and n Ch41 Each independently represents a natural number of 0 to 4, preferably 0, 1 or 2; Ch12 represents a natural number from 0 to 18, preferably 0, 1 or 2; Ch11 , A Ch21 , A Ch22 , A Ch31 , ACh32 , A Ch41 , B Ch11 , B Ch21 , B Ch22 , B Ch31 , B Ch32 and / or B. Ch41 When there are multiple, they may be the same or different.)

[0075] The polymerizable monomer may be a radically polymerizable or cationic polymerizable compound, preferably a polyfunctional radically polymerizable monomer, and more preferably a compound copolymerizable with the above-mentioned polymerizable group-containing liquid crystal compound. These may be used alone or in combination of two or more. The radical polymerizable monomer may have a double bond in its molecule.By using the radical polymerizable monomer having a double bond in its molecule, the strength of the optical film can be increased, but the viscosity of the retardation layer forming composition increases with the increase in the number of double bonds, so the number of double bonds in the radical polymerizable monomer is preferably 1 or more and 10 or less, and more preferably 1 or more and 8 or less.

[0076] The radical polymerizable monomer is preferably an ester condensate of a polyhydric alcohol and an unsaturated fatty acid. The polyhydric alcohol is preferably ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, dipentaerythritol hexaacrylate, 1,3-butylene glycol, tetramethylene glycol, hexamethylene glycol, neopentyl glycol, nonanediol, decanediol, trimethylolpropane, glycerin, pentaerythritol, or dipentaerythritol. The unsaturated fatty acid is preferably acrylic acid, methacrylic acid, maleic acid, or itaconic acid.

[0077] As the polymerizable monomer, a compound represented by the general formula (P1) is preferable, but it is not limited to these compounds.

[0078] [ka] In the formula, R P1 is R in general formula (D1). D1 It has the same meaning as P P1 is P in general formula (D1). D1 It has the same meaning as:

[0079] The retardation layer forming composition may not contain a polymerizable monomer, but when the functional layer (1) is formed by homeotropically aligning the rod-shaped liquid crystal, it is preferable that the polymerizable monomer is contained in order to impart vertical alignment. When the polymerizable monomer is contained, the content is preferably 2 to 50 mass % of the total amount of the polymerizable compound in the retardation layer forming composition, and more preferably 3 to 40 mass %.

[0080] (Method of applying retardation layer) The composition for forming the retardation layer can be applied by a known method (eg, wire bar coating method, extrusion coating method, direct gravure coating method, reverse gravure coating method, die coating method).

[0081] (Alignment film) The liquid crystal compound may be aligned by an alignment film. The alignment film has a role of facilitating alignment of the liquid crystal compound in the retardation layer when the retardation layer is formed by applying, drying and curing the composition for forming the retardation layer. Even if the retardation layer has an alignment film at the time of formation, the retardation layer can be transferred to another member and the alignment film can be prevented from being transferred during the transfer process to obtain an optical laminate without an alignment film.

[0082] The alignment film can be formed by, for example, applying an alignment layer-forming composition onto a transparent substrate and imparting an alignment control force to the composition. The alignment film-forming composition can be appropriately selected from conventionally known materials such as photodimerization-type materials. The means for imparting an alignment control force to the alignment film can be a conventionally known method, such as a rubbing method, a photoalignment method, a shaping method, or the like. The thickness of the alignment film is preferably 1 to 1,000 nm, and more preferably 60 to 300 nm.

[0083] [Function layer (2)] The functional layer (2) of the present invention is a plastic film different from the functional layer (1) described above, and is used in combination with the functional layer (1) to improve the reverse wavelength dispersion of the functional layer (1).

[0084] When the functional film is an A-plate film with reverse wavelength dispersion, the functional layer (1) becomes an A-plate. In this case, the functional layer (2) to be combined contains one or more non-polymerizable or polymerizable dichroic infrared absorbing dyes exhibiting positive dichroism as the dichroic infrared absorbing dye, and the functional layer (1) Orthogonal to the slow axis direction It is preferable that the major axis direction of the infrared absorbing portion is oriented approximately parallel to the direction of the infrared ray (configuration (1) or (2)).

[0085] The functional layer (2) is preferably a polymer of a polymerizable composition containing a polymerizable liquid crystal compound, and as shown in FIG. 5, the long axis direction of the mesogen of the polymerizable liquid crystal compound is aligned with that of the functional layer (1). Orthogonal to the slow axis direction It is preferable that the direction be substantially parallel to the direction.

[0086] The polymer liquid crystal is a polymer of a polymerizable liquid crystal compound, and the polymerizable liquid crystal compound can be the above-mentioned polymerizable liquid crystal compound. Only one type of polymerizable liquid crystal compound can be used, but two or more types can also be used, and a helical structure can be induced by further using an optically active compound. As the optically active compound, a general-purpose compound can be used, and is not particularly limited. The polymerizable liquid crystal compound is preferably aligned horizontally to the substrate by the alignment film. The alignment film may be a general-purpose horizontal alignment film. A means for imparting an alignment control force to the horizontal alignment film may be a conventionally known method, such as a rubbing method, a photoalignment method, or a shaping method. The thickness of the horizontal alignment film is usually from 1 to 1000 nm, and preferably from 60 to 300 nm.

[0087] [Dichroic infrared absorbing dye or its polymer] The functional layer (2) constituting the functional film in the present invention contains a polymer obtained by polymerizing a compound containing a non-polymerizable dichroic infrared absorbing dye or a dichroic infrared absorbing dye having a polymerizable group. A polymer obtained by polymerizing a compound containing a non-polymerizable dichroic infrared absorbing dye or a dichroic infrared absorbing dye having a polymerizable group has an infrared absorbing partial structure, and the partial structure has a structure in which π electrons are conjugated, as shown in Figure 2. The structure in which π electrons are conjugated has a rod-like shape (1 in Figure 2), and therefore has a long axis direction and a short axis direction of the infrared absorbing site, and since the long axis direction of the infrared absorbing site absorbs more infrared rays than the short axis direction, the polymer exhibits dichroism with respect to infrared absorption. Here, a dichroic infrared absorbing dye in which the orientation direction of the dichroic dye and the direction of the absorption axis are approximately the same exhibits positive dichroism, and a dichroic infrared absorbing dye in which the orientation direction of the dichroic dye and the direction of the absorption axis are approximately perpendicular exhibits negative dichroism. Note that the compound shown in Figure 2 is a positive dichroic dye because the long axis of the molecule and the infrared absorption axis are aligned.

[0088] Since the direction of the infrared absorption axis and the orientation state of the infrared absorbing partial structure are approximately the same, the orientation state of the infrared absorbing partial structure in the plastic film can be determined by the direction of the absorption axis for incident light of 750 nm.

[0089] Since the functional film is used in liquid crystal display elements and organic EL elements, which are image display devices, it is not preferable for the dichroic infrared absorbing dye or its polymer to have strong absorption in the visible light range, since if the dichroic infrared absorbing dye or its polymer inhibits the transmission of visible light, it will cause a change in the color tone of the image and a decrease in brightness. For this reason, plastic films containing one or more dichroic infrared absorbing dyes are Thickness direction The absorbance (I 750 ) and absorbance at 630 nm wavelength (I 630 ) ratio (I 750 / I 630) and / or one or more dichroic infrared absorbing dyes. Thickness direction The absorbance (I 800 ) and absorbance at 630 nm wavelength (I 630 ) and the ratio (I 800 / I 630 ) is preferably 3 or more, more preferably 5 or more, and even more preferably 10 or more; (I 800 / I 630 ) is preferably 5 or more, and more preferably 10 or more. It is also preferable that there is an absorbance peak with a half-width of 50 nm or less on the wavelength side longer than 750 nm. In the present invention, the absorbance peak means a wavelength showing an absorption maximum in the spectroscopic absorption spectrum in the wavelength region of 750 to 850 nm, and when there are multiple absorption maxima, it means an absorption maximum wavelength showing the maximum absorbance among them.

[0090] In the present invention, a polymer obtained by polymerizing a compound containing a non-polymerizable dichroic infrared absorbing dye or a dichroic infrared absorbing dye having a polymerizable group is used to improve the reverse wavelength dispersion of a functional film. A film made of a polymer obtained by polymerizing a polymerizable liquid crystal compound exhibiting conventional reverse wavelength dispersion exhibits reverse wavelength dispersion by introducing a structure having a mesogen portion that exhibits liquid crystallinity as the polymerizable liquid crystal compound and having a conjugated system of π electrons in the minor axis direction of the molecule. However, in the conventional method using only a polymerizable liquid crystal compound, deviation from the ideal curve (A) was observed in the long wavelength region of visible light, as shown in (B) of Figure 1. For this reason, in the present invention, by using an infrared absorbing dye that has low absorbance in the visible light region and increases absorbance toward the infrared region and has dichroism, the in-plane retardation in the long wavelength region of visible light can be increased and the curve can be brought closer to the ideal curve (A) of wavelength dispersion. In particular, the configuration of the present invention is useful for producing a functional film having the properties of an A plate.

[0091] The polymer obtained by polymerizing a compound containing a non-polymerizable dichroic infrared absorbing dye or a dichroic infrared absorbing dye having a polymerizable group may be used alone or in combination of two or more. As shown in Figure 3, it is possible to approach the ideal wavelength dispersive curve (A) by using one infrared absorbing dye having wavelength dispersive properties such as (C), but it is also possible to approach the ideal wavelength dispersive curve (A) by combining compounds having wavelength dispersive properties such as (D) and (E) as shown in Figure 4.

[0092] In the present invention, the functional layer (1) satisfies the relationship of nx>ny and has the characteristics of a positive A plate or a negative A plate. In order to improve the wavelength dispersion in the long wavelength region of visible light in this functional film, the major axis of the infrared absorbing partial structure is aligned in the direction of the functional layer (1). Orthogonal to the slow axis direction It is preferable to arrange the electrodes approximately horizontally in the direction.

[0093] The compound having the structure shown in FIG. 2 is appropriately oriented and polymerized as necessary to improve the reverse wavelength dispersion.

[0094] The dichroic infrared absorbing dye is contained in at least one of the functional layers (2), and it is preferable to apply a composition containing a polymerizable liquid crystal compound, a positive dichroic infrared absorbing dye (illustrated in FIG. 2), an initiator and a solvent to a substrate, evaporate off the solvent, and then irradiate with ultraviolet light to form a plastic film. The positive dichroic infrared absorbing dye may be a polymerizable compound or a non-polymerizable compound.

[0095] In this case, the infrared absorption axis of the positive dichroic infrared absorbing dye is aligned with other polymerizable liquid crystal compounds by the horizontal alignment film, and the alignment direction is aligned with the direction of the plastic film. Orthogonal to the slow axis direction It is preferable that the direction be substantially parallel to the direction of the optical axis in order to improve the reverse wavelength dispersion. Orthogonal to the slow axis direction Since the infrared absorption axis is in the direction, the reverse wavelength dispersion can be improved. Therefore, the functional layer (2) manufactured in this manner has the same properties as the functional layer (1). Slow axis direction and Thickness Infrared absorption in a direction Orthogonal to the slow axis direction Since the wavelength dispersion is smaller than that of the optical fiber, the reverse wavelength dispersion can be effectively improved. Orthogonal to the slow axis direction Not just the direction Thickness In contrast, when the configuration of the present invention is adopted, there is an excellent effect that the amount of the positive dichroic infrared absorbing dye added can be reduced, or the film thickness can be made thinner even with the same amount added.

[0096] Furthermore, since a dichroic infrared absorbing dye generally has low compatibility with other compounds, there are problems in that the dye precipitates over time when made into a polymerizable composition, or that the dye does not dissolve in a required amount in the first place. However, in the present invention, which is effective with a small amount of the dye, these problems do not occur or can be minimized. Furthermore, in the case of the present invention, a positive dichroic compound can be used as the dichroic infrared absorbing dye, and it may be a non-polymerizable dichroic infrared absorbing dye. As the non-polymerizable dichroic infrared absorbing dye, a commercially available compound can be used, so there is a wide range of choices, and it is possible to select a compound that has no compatibility problems. The invention described in Patent Document 2 requires a dichroic infrared absorbing dye with negative dichroism, which is difficult to obtain. Furthermore, a dichroic infrared absorbing dye having a polymerizable group is preferred because it is incorporated into a polymer chain together with other polymerizable compounds, thereby increasing the durability of the functional film.

[0097] In the present invention, an embodiment including two or more functional layers (1) including a dichroic infrared absorbing dye or a polymer thereof, or an embodiment including a plurality of functional layers (2) including a dichroic infrared absorbing dye or a polymer thereof is also preferred.

[0098] The infrared absorbing partial structure is not particularly limited as long as it exhibits dichroism and has absorption in the infrared region as described above, but preferred are a cyanine skeleton, a squarylium skeleton, a pyrylium skeleton, an azo skeleton, an anthraquinone skeleton, a dithiolene skeleton, a diimonium skeleton, and the like.

[0099] The dichroic infrared absorbing dye or the dichroic infrared absorbing dye having a polymerizable group is preferably a compound represented by the following general formulas (IR1) to (IR8).

[0100] [ka]

[0101] In the formula, A IR11 represents a substituent represented by general formulae (AIR11-1) to (AIR11-6),

[0102] [ka] (In the formula, the dashed double bond and the dashed single bond represent A IR11 represents a double bond and a single bond to which R IR11 and R IR12 each independently represents R in general formula (D1). D1 It has the same meaning as A IR12 represents a substituent represented by general formulae (AIR12-1) to (AIR11-16),

[0103] [ka]

[0104] [ka]

[0105] (In the formula, the dashed single bond represents A IR12 represents a single bond to which R IR13 , R IR14 and R IR15 each independently represents R in general formula (D1). D1 It has the same meaning as A IR13 represents a substituent represented by general formulae (AIR13-1) to (AIR13-29),

[0106] [ka]

[0107] [ka]

[0108] [ka]

[0109] (In the formula, the dashed double bond represents A IR13 represents the double bond to which IR13 , R IR14 and R IR15 each independently represents R in general formula (D1). D1 It has the same meaning as A IR11 , R IR11 , R IR12 , R IR13 , R IR14 and / or R IR15 When a plurality of these are present in a molecule, they may be the same or different.

[0110] [ka]

[0111] In the formula, A IR21 A IR12 It has the same meaning as A IR22 A IR13 It has the same meaning as:

[0112] [ka]

[0113] In the formula, R IR41 ~R IR45 each independently represents a substituent represented by general formula (RIR4).

[0114] [ka]

[0115] (In the formula, R IR48 is R in general formula (D1). D1 It has the same meaning as A IR41 is preferably a divalent group having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocycle which may have a substituent, or a divalent group having an aliphatic hydrocarbon ring which may have a substituent, and is preferably the following groups (a), (b), and (c). (a) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may be replaced by -O-), (b) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=); and (c) a biphenyl-4,4'-diyl group, a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (provided that one -CH= or two or more non-adjacent -CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by -N=),

[0116] wherein the hydrogen atoms in the groups (a), (b) and (c) each independently represent an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyloxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, a cyano group, a fluorine atom, a chlorine atom or -Sp D1 -P D1 may be substituted with B IR41 is B in general formula (D1). D1 It means the same as n IR41is n in general formula (D1). D2 It has the same meaning as R IR48 , A IR41 , B IR41 and / or n IR41 When there are multiple Bs, they may be the same or different. IR41 Radical with hydrogen atom removed and / or R IR48 The radicals formed by removing hydrogen atoms from the ring may be bonded to form a ring structure.) As the compound represented by general formula (IR4), the compounds represented by general formulas (IR4-1) to (IR4-3) are preferable.

[0117] [ka]

[0118] In the formula, the general formula R IR46 and R IR47 Each independently represents a substituent represented by the general formula (RIR4), but IR46 and / or R IR47 When there are a plurality of, they may be the same or different.

[0119] [ka] (In the formula, R IR48 is R in general formula (D1). D1 It has the same meaning as A IR41 is preferably a divalent group having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocycle which may have a substituent, or a divalent group having an aliphatic hydrocarbon ring which may have a substituent, and is preferably the following groups (a), (b), and (c). (a) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may be replaced by -O-), (b) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=); and (c) a biphenyl-4,4'-diyl group, a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (provided that one -CH= or two or more non-adjacent -CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by -N=),

[0120] wherein the hydrogen atoms in the groups (a), (b) and (c) each independently represent an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyloxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, a cyano group, a fluorine atom, a chlorine atom or -Sp D1 -P D1 may be substituted with B IR41 is B in general formula (D1). D1 It means the same as n IR41 is n in general formula (D1). D2 It has the same meaning as R IR48 , A IR41 , B IR41 and / or n IR41 When there are multiple, they may be the same or different.)

[0121] [ka] In the formula, the general formula R IR51 and R IR52 each independently represents a substituent represented by general formula (RIR5).

[0122] [ka]

[0123] (In the formula, R IR53 is R in general formula (D1). D1 It has the same meaning as A IR51 is preferably a divalent group having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocycle which may have a substituent, or a divalent group having an aliphatic hydrocarbon ring which may have a substituent, and is preferably the following groups (a), (b), and (c). (a) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may be replaced by -O-), (b) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=); and (c) a biphenyl-4,4'-diyl group, a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (provided that one -CH= or two or more non-adjacent -CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by -N=),

[0124] wherein the hydrogen atoms in the groups (a), (b) and (c) each independently represent an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyloxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, a cyano group, a fluorine atom, a chlorine atom or -Sp D1 -P D1 may be substituted with B IR51 is B in general formula (D1). D1 It means the same as n IR51 is n in general formula (D1). D2 It has the same meaning as R IR53, A IR51 , B IR51 and / or n IR51 When there are multiple, they may be the same or different.)

[0125] [ka]

[0126] In the formula, the general formula R IR61 ~R IR64 each independently represents a substituent represented by general formula (RIR6).

[0127] [ka]

[0128] (In the formula, R IR65 is R in general formula (D1). D1 It has the same meaning as A IR61 is preferably a divalent group having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocycle which may have a substituent, or a divalent group having an aliphatic hydrocarbon ring which may have a substituent, and is preferably the following groups (a), (b), and (c). (a) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may be replaced by -O-), (b) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=); and (c) a biphenyl-4,4'-diyl group, a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (provided that one -CH= or two or more non-adjacent -CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by -N=),

[0129] wherein the hydrogen atoms in the groups (a), (b) and (c) each independently represent an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyloxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, a cyano group, a fluorine atom, a chlorine atom or -Sp D1 -P D1 may be substituted with B IR61 is B in general formula (D1). D1 It means the same as n IR61 is n in general formula (D1). D2 It has the same meaning as R IR65 , A IR61 , B IR61 and / or n IR61 When there are multiple, they may be the same or different.)

[0130] [ka]

[0131] In the formula, the general formula R IR71 represents a substituent represented by the general formula (RIR7), but there are multiple R IR71 may be the same or different.

[0132] [ka]

[0133] (In the formula, R IR72 is R in general formula (D1). D1 It has the same meaning as A IR71 is preferably a divalent group having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocycle which may have a substituent, or a divalent group having an aliphatic hydrocarbon ring which may have a substituent, and is preferably the following groups (a), (b), and (c). (a) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may be replaced by -O-), (b) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=); and (c) a biphenyl-4,4'-diyl group, a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (provided that one -CH= or two or more non-adjacent -CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by -N=),

[0134] wherein the hydrogen atoms in the groups (a), (b) and (c) each independently represent an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyloxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, a cyano group, a fluorine atom, a chlorine atom or -Sp D1 -P D1 may be substituted with B IR71 is B in general formula (D1). D1 It means the same as n IR71 is n in general formula (D1). D2 It has the same meaning as R IR72 , A IR71 , B IR71 and / or n IR71 When there are multiple, they may be the same or different.)

[0135] [ka] In the formula, the general formula R IR81 represents a substituent represented by the general formula (RIR8), but there are multiple RIR81 may be the same or different.

[0136] [ka] (In the formula, R IR82 is R in general formula (D1). D1 It has the same meaning as A IR81 is preferably a divalent group having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocycle which may have a substituent, or a divalent group having an aliphatic hydrocarbon ring which may have a substituent, and is preferably the following groups (a), (b), and (c). (a) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may be replaced by -O-), (b) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=); and (c) a biphenyl-4,4'-diyl group, a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (provided that one -CH= or two or more non-adjacent -CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by -N=),

[0137] wherein the hydrogen atoms in the groups (a), (b) and (c) each independently represent an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkenyloxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, a cyano group, a fluorine atom, a chlorine atom or -Sp D1 -P D1 may be substituted with B IR81 is B in general formula (D1).D1 It means the same as n IR81 is n in general formula (D1). D2 It has the same meaning as R IR82 , A IR81 , B IR81 and / or n IR81 When there are multiple, they may be the same or different.)

[0138] As a preferred structure of the polymerizable compound different from the infrared and ultraviolet absorbing dye, the same compounds as those in the functional layer (1) can be used.

[0139] [Dichroic UV absorbing dye] In the present invention, the wavelength dispersion in the long wavelength region of visible light is improved by using a polymer obtained by polymerizing a compound containing a non-polymerizable dichroic ultraviolet absorbing dye or a dichroic ultraviolet absorbing dye having a polymerizable group, but it is also preferable to further use a dichroic ultraviolet absorbing dye or a polymer thereof to improve the wavelength dispersion in the short wavelength region as well, thereby approaching the ideal curve of the inverse wavelength dispersion (as shown in FIG. 6).

[0140] A polymer obtained by polymerizing a compound containing a non-polymerizable dichroic ultraviolet absorbing dye or a dichroic ultraviolet absorbing dye having a polymerizable group has a structure that absorbs ultraviolet light. The structure is preferably a benzoxazinone skeleton, a benzotriazole skeleton, an azomethine skeleton, an azoxy skeleton, a cyanobiphenyl skeleton, a cyanophenyl ester skeleton, a benzoate skeleton, a cyclohexane carboxylic acid phenyl esters, cyanophenyl cyclohexanes, a phenylpyrimidine skeleton, a phenyldioxane skeleton or a tolane skeleton, and more preferably a benzoxazinone skeleton, a benzotriazole skeleton, an azomethine skeleton or an azoxy skeleton. A polymer obtained by polymerizing a compound containing a non-polymerizable dichroic ultraviolet absorbing dye or a dichroic ultraviolet absorbing dye having a polymerizable group has similar characteristics to a polymer obtained by polymerizing a compound containing a non-polymerizable dichroic infrared absorbing dye or a dichroic infrared absorbing dye having a polymerizable group, except for having an ultraviolet absorbing partial structure, and the orientation and orientation method of the ultraviolet absorbing partial structure have similar characteristics to those of the infrared absorbing partial structure, so description thereof will be omitted. As the compound having a benzoxazinone skeleton or a benzotriazole skeleton, one or more compounds selected from the compounds represented by the general formulae (U1) and (U2) are preferable.

[0141] [ka]

[0142] (In the general formulas (U1) and (U2), X U11 ~X U29 each independently represents a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or -S in the general formula (D1). D1 -P D1 In the alkyl and alkenyl groups, one or more hydrogen atoms are replaced by a fluorine atom, a chlorine atom, or -Sp D1 -P D1 In the alkyl group and the alkenyl group, one or more -CH2- may be substituted with -O-, -COO-, -OCO-, -NH-, -CONH-, -NHCO-, -CH=CH- or -C≡C-, in which case a plurality of -CH2- may be substituted, which may be the same or different, and in the alkyl group and the alkenyl group, one or more -CH2- may be substituted with -O-, -COO-, -OCO-, -NH-, -CONH-, -NHCO-, -CH=CH- or -C≡C-, in which case a plurality of -CH2- may be substituted, which may be the same or different, U11 ~X U29 may each independently be a group represented by general formula (U3), U11 represents B in general formula (D1). D1 Or A D2 In general formula (U3), A U31 is A in general formula (D1). D2It has the same meaning as B U31 is B in general formula (D1). D1 and R U31 is R in general formula (D1). D2 It has the same meaning as R U31 The hydrogen atom in is -Sp D1 -P D1 may be substituted by n U31 represents a natural number from 1 to 3, and Sp D1 and / or P D1 When there are multiple, they may be the same or different.) More specifically, the compounds represented by the general formulae (U11) to (U21) are preferred.

[0143] [ka]

[0144] (In the formula, RU11 and RU12 each independently represent an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms, and one or more hydrogen atoms in the alkyl group and the alkenyl group are replaced with a fluorine atom, a chlorine atom, or -Sp D1 -P D1 In the alkyl group and the alkenyl group, one or more -CH2- may be substituted with -O-, -COO-, -OCO-, -NH-, -CONH-, -NHCO-, -CH=CH- or -C≡C-, in which case a plurality of -CH2- may be substituted, which may be the same or different, D1 and P D1 is Sp in general formula (D1). D1 and P D1 It has the same meaning as

[0145] Since the dichroic ultraviolet absorbing dye or its polymer is also used in an image display device, it is not preferable to strongly inhibit the transmission of visible light. For this reason, the use of a plastic film containing one or more dichroic ultraviolet absorbing dyes Thickness directionThe absorbance (I 350 ) and absorbance at 420 nm (I 420 ) ratio (I 350 / I 420 ) is preferably 10 or more, more preferably 15 or more, and even more preferably 20 or more. It is also preferable that there is an absorbance peak with a half-width of 50 nm or less on the wavelength side shorter than 350 nm.

[0146] <Functional layer (3)> The functional layer (3) is a layer different from the functional layer (1) and the functional layer (2). Examples of the functional layer (3) include a polarizing plate, a positive C layer, a substrate used in producing the functional layer (1) and the functional layer (2), an alignment film layer, a hard coat layer, a low refractive index layer, a high refractive index layer, an antiglare layer, an antifouling layer, an antistatic layer, a gas barrier layer, an antifogging layer, and a transparent conductive layer. The functional layer may be one selected from the above-mentioned layers, or may be a laminate of two or more layers. The functional layer may also be a combination of two or more of the above-mentioned functions. That is, in this specification, the term "hard coat layer", "low refractive index layer", "high refractive index layer", "antiglare layer", "antifouling layer", "antistatic layer", "gas barrier layer", "anti-fogging layer" and "transparent conductive layer" refers not only to a functional layer having a single function, but also to a functional layer having a composite function. For example, the hard coat layer includes an antifouling hard coat layer, an antiglare hard coat layer and a high refractive index hard coat layer. The antifouling layer includes an antiglare antifouling layer and a low refractive index antifouling layer. A polarizing plate and a positive C layer, which are typical examples of functional layers, will be specifically described below.

[0147] <Polarizing plate> The polarizing plate of the present invention has a polarizer. The polarizing plate is used, for example, in combination with a λ / 4 retardation plate to impart anti-reflection properties. In this case, the λ / 4 retardation plate is disposed on the image display device, and the polarizing plate is disposed closer to the viewer than the λ / 4 retardation plate.

[0148] <Polarizer> Examples of polarizers include sheet-type polarizers such as polyvinyl alcohol films, polyvinyl formal films, polyvinyl acetal films, and saponified ethylene-vinyl acetate copolymer films dyed with iodine or the like and stretched, wire-grid-type polarizers made of a large number of metal wires arranged in parallel, coating-type polarizers coated with lyotropic liquid crystal or a dichroic guest-host material, and multilayer thin-film-type polarizers. These polarizers may be reflective polarizers that have the function of reflecting polarized components that are not transmitted.

[0149] The polarizer is preferably arranged so that its absorption axis is approximately parallel or approximately perpendicular to any one side of the sample of the optical biaxially stretched plastic film cut out according to the above-mentioned method. Approximately parallel means within 0 degrees ±5 degrees, preferably within 0 degrees ±3 degrees, more preferably within 0 degrees ±1 degree. Approximately perpendicular means within 90 degrees ±5 degrees, preferably within 90 degrees ±3 degrees, more preferably within 90 degrees ±1 degree.

[0150] <Positive C layer> In a liquid crystal display device, the functional film is preferably a retardation layer in which a positive A layer and a positive C layer are combined in order to increase the contrast with respect to a viewing angle from an oblique direction.

[0151] A positive C layer has the characteristic that when the refractive index in the X-axis direction along the layer surface is nx, the refractive index in the Y-axis direction along the layer surface and perpendicular to the X-axis is ny, and the refractive index in the layer thickness direction is nz>nx≒ny, and the optical axis is in the z direction. For example, it can be formed by applying, on a transparent substrate, an ink for forming a positive C layer, which contains components constituting the positive C layer and a solvent, followed by drying and curing. The content of the liquid crystal compound in the ink for forming the positive C layer is not particularly limited, but is preferably 5% by mass or more and 40% by mass or less, and more preferably 10% by mass or more and 30% by mass or less. If the amount of the liquid crystal compound is less than 5% by mass, a large amount of ink needs to be applied to the transparent substrate, making production difficult, and a large amount of solvent needs to be removed, which is likely to cause a deterioration in reliability due to the remaining solvent. On the other hand, if the amount exceeds 40% by mass, the viscosity of the polymerizable liquid crystal composition becomes too high, making the workability of producing the positive C layer poor. The content of the liquid crystal compound relative to the solid mass (mass excluding the solvent) of the ink for forming the positive C layer is preferably 75 to 99.9 mass %, more preferably 80 to 99 mass %, and further preferably 85 to 98 mass %.

[0152] The ink for forming the positive C layer may contain a polymerization initiator, a leveling agent, an alignment promoter, and the like. The thickness of the positive C layer can be appropriately adjusted taking into consideration the retardation value to be imparted, and is usually about 0.1 to 10 μm. The positive C layer may be a layer exhibiting reverse wavelength dispersion, or may be a layer exhibiting reverse wavelength dispersion by combining a positive C layer with a positive C layer containing a dichroic infrared absorbing dye or a polymer thereof.

[0153] <Adhesive layer> The adhesive used in the adhesive layer of the present invention is not particularly limited, and can be appropriately selected and used, for example, those having acrylic polymers, silicone polymers, polyesters, polyurethanes, polyamides, polyethers, fluorine-based polymers, rubber-based polymers, etc. as base polymers. The adhesive is required to have excellent adhesive properties such as optical transparency, moderate wettability, cohesiveness, adhesion, weather resistance, heat resistance, etc. Furthermore, an adhesive layer with low moisture absorption rate and excellent heat resistance is required from the viewpoints of preventing foaming phenomenon and peeling phenomenon due to moisture absorption, preventing deterioration of optical properties and warping of liquid crystal cells due to thermal expansion difference, etc., and thus forming an image display device with high quality and excellent durability. From this viewpoint, acrylic adhesives are preferred.

[0154] The adhesive may contain, for example, natural or synthetic resins, particularly tackifying resins, and additives such as fillers made of glass fibers, glass beads, metal powder, other inorganic powders, etc., pigments, colorants, antioxidants, etc. The adhesive layer may also contain fine particles and exhibit light diffusing properties.

[0155] The application of the above-mentioned adhesive to the polarizing plate of the present invention is not particularly limited and can be performed by a suitable method. For example, a method of preparing an adhesive solution of about 10 to 40 mass % by dissolving or dispersing a base polymer or its composition in a solvent consisting of a single or mixture of suitable solvents such as toluene and ethyl acetate, and directly applying it to the polarizing plate of the present invention by a suitable spreading method such as a casting method or a coating method, or a method of forming an adhesive layer on a releasable base film according to this method and transferring it to the polarizing plate of the present invention, etc. can be mentioned. Various coating methods are possible, such as gravure coating, bar coating, roll coating, reverse roll coating, and comma coating, with gravure coating being the most common.

[0156] The pressure-sensitive adhesive layer can be provided on one or both sides of the polarizing plate of the present invention as a superposed layer of layers having different compositions or types. When provided on both sides, the pressure-sensitive adhesives on the front and back of the polarizing plate of the present invention do not need to have the same composition or thickness. Pressure-sensitive adhesive layers of different compositions and thicknesses can also be used. The thickness of the pressure-sensitive adhesive layer can be appropriately determined depending on the purpose of use, adhesive strength, etc., and is generally 1 μm to 500 μm, preferably 5 μm to 200 μm, and particularly preferably 10 μm to 100 μm.

[0157] <Application> The functional film of the present invention can be suitably used as a plastic film for an image display device. As described above, the functional film can be used in a liquid crystal display device for the purpose of improving the viewing angle characteristics derived from the alignment state of liquid crystal molecules, and in an organic EL device for the purpose of reducing the reflection of external light by a metal electrode.

[0158] When used as a liquid crystal display element, an IPS liquid crystal display device (IPS-LCD) is preferable.

[0159] In IPS-LCD, liquid crystal compounds change their alignment state in a plane approximately parallel to the substrate by turning on and off the voltage. In an IPS-type liquid crystal display element equipped with the functional film of the present invention, color variation due to oblique viewing angles when viewed obliquely is suppressed by further combining it with a positive A plate. When the functional film of the present invention is used, it functions as an optical compensation film from an oblique viewing angle in a wide band.

[0160] When used in this organic EL element, the functional film of the present invention functions as a part of an external light antireflection film arranged on the emission surface side of the organic EL element. The functional film of the present invention is used together with a polarizer for linear polarization and a retardation film, and has an external light antireflection function as a so-called circular polarizing plate. The positive A plate of the retardation film functions as a λ / 4 retardation layer, and a positive C plate is laminated thereon. EXAMPLES

[0161] 1. Preparation of Plastic Films for Evaluation 1-1. Preparation of a solution containing a polymerizable liquid crystal composition The compositions used in the preparation of the plastic films used in Examples 1 to 4 and Comparative Examples 1 and 2 are summarized in Table 2.

[0162] [Table 2]

[0163] 1: Omnirad907 (manufactured by IGM Resins BV) was used as the initiator.

[0164] As shown in Table 2, a composition was prepared by containing a compound represented by formula (LC1) or (LC2) as a polymerizable liquid crystal compound, a compound represented by formulas (IR1) to (IR6) as a dichroic infrared absorbing dye, a compound represented by formula (UV1) or (UV2) as a dichroic infrared absorbing dye, and further adding an initiator and cyclohexanone as a solvent.

[0165] [ka]

[0166] [ka]

[0167] [ka]

[0168] [ka]

[0169] [ka]

[0170] [ka]

[0171] [ka]

[0172] [ka]

[0173] [ka]

[0174] 1-2. Preparation of plastic film The plastic films were prepared using the above-mentioned compositions 1 and 2, which are polymerizable liquid crystal compositions for positive A plates, and positive A compositions (dye compositions) 1 to 9, according to procedure 1 (see Table 2).

[0175] Step 1: Making the positive A plate A photo-alignment film for horizontal alignment was applied to the surface of a 100 μm-thick PET substrate that did not have an easy-adhesion layer. Then, polarized UV was applied at 50 mJ / cm 2 After irradiation with ultraviolet light (wavelength 365 nm), Composition 1 was applied using a bar coater and dried for 60 seconds at the drying temperature shown in Table 3. The applied surface was then irradiated with ultraviolet light (wavelength 365 nm), and then irradiated with ultraviolet light (wavelength 365 nm). 2 The coating was cured by exposure to ultraviolet light (wavelength 365 nm) to produce coating film 1 with a thickness of approximately 2 μm. Positive A coating films (dye coating films) 1 to 6 were obtained in the same manner, except that positive A compositions (dye compositions) 1 to 6 were used instead of composition 1.

[0176] The physical properties of each coating are summarized in Table 3.

[0177] [Table 3]

[0178] 2. Evaluation 2-1. In-plane phase difference (Re) The in-plane retardation of the above-mentioned coating film was measured. The measuring device used was a product name "RETS-100 (measurement spot: diameter 5 mm)" manufactured by Otsuka Electronics Co., Ltd. Re represents the in-plane retardation, and the unit is nm. Re 450 is the wavelength of 450 nm, Re 550 is the wavelength of 550 nm, Re 650 is the in-plane retardation at a wavelength of 650 nm. This retardation was measured using a KOBRA-WR manufactured by Oji Scientific Instruments Co., Ltd. in the wavelength dispersion characteristic measurement mode with the tilt central axis set to the leading axis. 2-2.Absorbance (I) I630 is a plastic film Thickness This is the transmittance of transmitted light for incident light with a wavelength of 630 nm from the direction of the sample. It was measured using a UV-visible spectrophotometer "UVPC-2450" (Shimadzu Corporation) at a wavelength of 630 nm (I 630 ) and 800 nm (I 800 ) was measured.

[0179] (Examples 1 to 4 and Comparative Examples 1 and 2) Table 4 shows the physical properties of the functional films of Examples 1 to 10 and Comparative Example 1.

[0180] [Table 4]

[0181] <Front color> An organic EL display device was produced by using the produced optical laminate in place of the circular polarizer of the organic EL display panel and each layer provided on the viewing side of the circular polarizer. The obtained organic EL display device was observed from the front with a black screen when the power was off, and was evaluated by the following sensory evaluation. The sensory evaluation was carried out by 20 panelists, and the result with the largest number of panelists was adopted. In addition, when there were two evaluations with the largest number of panelists, the evaluation with the worst result was adopted. A: No redness B: Slightly reddish, but usable C: Too reddish and not suitable for practical use

[0182] In the evaluation of the front color of Examples 1 to 10 of the present invention, no redness was felt, or even if a reddish tint was felt, it was sufficiently usable. In contrast, in Comparative Example 1, the redness was too strong, making it unusable. Thus, it was found that practical optical compensation could be achieved by using the positive A coating film of the present invention. [Explanation of symbols]

[0183] (A) Schematic diagram of an ideal inverse wavelength dispersion curve (B) Schematic diagram of wavelength dispersion curve of functional film using conventional compound (C) Schematic diagram of absorbance curve of dichroic infrared absorbing dye (D) Schematic diagram of absorbance curve of dichroic infrared absorbing dye (E) Schematic diagram of absorbance curve of dichroic infrared absorbing dye 1.Dichroic infrared absorbing dye 2. Substructure that absorbs infrared rays 3. Mesogen Moiety Optionally Having a Side Chain Moiety and a Polymerizable Group 4. Dichroic infrared absorbing dye having a dichroic infrared absorbing site

Claims

1. A functional film including at least two functional layers, When the refractive index in the in-plane direction of the slow axis of the functional layer (1) is nx, the refractive index in the in-plane direction perpendicular to the slow axis direction is ny, and the refractive index in the thickness direction of the functional layer (1) is nz, the relationship of nx>ny is satisfied, the functional layer (2) contains one or more positive dichroic infrared absorbing dyes or polymers thereof, and a polymer of a polymerizable composition containing a polymerizable liquid crystal compound; A functional film in which the absorption axis direction of at least the positive dichroic infrared absorbing dye with respect to incident light of 750 nm is approximately perpendicular to the slow axis direction of the functional layer (1) in the in-plane direction.

2. The functional film according to claim 1 , wherein the functional layer (1) satisfies nx>ny≈nz.

3. The functional film according to claim 1 , wherein the functional layer (1) satisfies nx≈nz>ny.

4. The functional film according to any one of claims 1 to 3, wherein in the functional layer (2), the long axis direction of the mesogen of the polymerizable liquid crystal compound is approximately parallel to a direction perpendicular to the slow axis direction of the functional layer (1), and the positive dichroic infrared absorbing dye is oriented along the long axis direction of the mesogen of the polymerizable liquid crystal compound.

5. The absorbance (I ７５０ ) and absorbance for light of 630 nm wavelength (I ６３０ ) ratio (I ７５０ / I ６３０ 5. The functional film according to claim 1, wherein the number of the first and second electrodes is 3 or more.

6. 6. The functional film according to claim 1, further comprising one or more dichroic ultraviolet absorbing dyes or polymers thereof in at least one of the functional layers.

7. The in-plane retardation (Re) of the functional film for light with a wavelength of 450 nm ４５０), the in-plane retardation (Re ５５０ ) and the in-plane retardation (Re ６５０ )but, R ４５０ / Re ５５０ <1.0 R ６５０ / Re ５５０ >1.0 The functional film according to any one of claims 1 to 6, which satisfies the above relationships.

8. The functional film according to any one of claims 1 to 7, further comprising a functional layer (3), the functional layer (3) being a functional layer of a positive C plate.

9. The functional film according to any one of claims 1 to 8, further comprising a functional layer (3), the functional layer (3) comprising a linear polarizing plate.

10. 10. An image display device comprising the functional film according to claim 1 on a light exit surface of a display element.

11. The image display device according to claim 10, wherein the image display device is an organic electroluminescence display device and has a metal electrode in a light-emitting layer.

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