Laminate

Abstract

The present invention provides a laminate with which it is possible to obtain an image display device that provides a bright field of view without blackout even when an image is viewed through polarized sunglasses. The laminate according to the present invention includes an optical film, a polarizer, and a liquid crystal layer 2 in this order. The optical film includes a substrate, an alignment film, and a liquid crystal layer 1 in this order. The optical film has an in-plane retardation of 70-143 nm at a wavelength of 550 nm.

Description

Laminate

[0001] This invention relates to a laminate for obtaining a bright field of view without blackout when viewing a display while wearing polarized sunglasses.

[0002] Conventionally, in image display devices, a method is known in which a circular polarizer is placed on the viewing side of the image display panel to suppress the decrease in visibility due to reflection of ambient light. A circular polarizer is an optical laminate that includes a polarizer and an optical film (for example, a phase difference film such as a quarter-wave plate). For example, a configuration like that shown in Patent Document 1 below is known.

[0003] International Publication No. 2019 / 160044

[0004] In recent years, image display devices are sometimes viewed through polarized sunglasses. When an observer wearing polarized sunglasses views an image displayed on an image display device that uses a polarizing plate on the light-emitting side, the screen may appear completely black (blackout) or the field of view may become dark. The present invention aims to provide a laminate that allows for an image display device with a bright field of view without blackout, even when viewing the image through polarized sunglasses.

[0005] The inventors of the present invention have conducted extensive research on the above-mentioned problems and have found that the above problems can be achieved with the following configuration.

[0006] (1) A laminate comprising an optical film, a polarizer, and a liquid crystal layer 2 in that order, wherein the optical film comprises a substrate, an alignment film, and a liquid crystal layer 1 in that order, and the in-plane retardation of the optical film at a wavelength of 550 nm is 70 to 143 nm. (2) The laminate according to (1), wherein the polarizer is arranged on the liquid crystal layer 1 side of the optical film. (3) The laminate according to (1) or (2), wherein the total thickness of the optical film is 45 μm or less. (4) The laminate according to any one of (1) to (3), wherein the alignment film is obtained by curing a composition having a photo-aligning polymer having a photo-aligning group and at least one selected from a radical-polymerizable group and a cationic-polymerizable group. (5) The laminate according to any one of (1) to (4), wherein the alignment film is obtained by curing a composition having a photo-aligning polymer having a photo-aligning group, a radical-polymerizable group, and a cationic-polymerizable group. (6) The laminate according to (4) or (5), wherein the alignment film is a photo-alignment film obtained by curing a photo-alignment film forming composition containing a photo-aligning polymer and an epoxy compound, the content of the photo-aligning polymer is 10 to 50% by mass with respect to the total solid content of the photo-alignment film forming composition, and the epoxy equivalent A of the epoxy compound, represented by the following formula, is 300 or less. (Formula) A = Mw / n Mw represents the molecular weight of the epoxy compound, and n represents the number of epoxy groups contained in one molecule of the epoxy compound. (7) The laminate according to any one of (1) to (6), wherein a hard coat layer is provided on the side of the substrate opposite to the side on which the alignment film is provided. (8) The laminate according to any one of (1) to (7), wherein the transmittance of the optical film at a wavelength of 380 nm is 20% or less. (9) The optical film according to any one of (1) to (8), wherein the substrate is a triacetylcellulose substrate. (10) The laminate according to any one of (1) to (9), wherein the angle between the slow axis of the optical film and the absorption axis of the polarizer is 30 to 60 degrees. (11) The laminate according to any one of (1) to (10), wherein the liquid crystal layer 2 is composed of one or more liquid crystal layers, and the liquid crystal layer 2 has a λ / 4 function.

[0007] According to the present invention, it is possible to provide a laminate that can obtain an image display device with a bright field of view without blackout, even when viewing an image through polarized sunglasses.

[0008] The embodiments of the present invention will be described in detail below. In this specification, numerical ranges expressed using "~" mean a range that includes the numbers before and after it as the lower and upper limits, respectively. The following descriptions of constituent elements may be based on representative embodiments and specific examples, but the present invention is not limited to such embodiments. Furthermore, "orthogonal" and "parallel" in relation to angles mean a range of ±10° from the exact angle, and "same" and "different" in relation to angles can be determined based on whether the difference is less than 5°. In this specification, "visible light" refers to 380 nm to 780 nm. In this specification, unless otherwise specified, the measurement wavelength is 550 nm. Next, the terms used in this specification will be explained.

[0009] <Slow Axis> In this specification, the "slow axis" refers to the direction in which the refractive index is maximum within the plane. When referring to the slow axis of a phase difference film, it refers to the slow axis of the entire phase difference film.

[0010] <Re(λ), Rth(λ)> In this specification, Re(λ) and Rth(λ) represent the in-plane retardation and thickness-direction retardation at wavelength λ, respectively. The values ​​for in-plane retardation and thickness-direction retardation are those measured using an AxoScan OPMF-1 (manufactured by OptoScience Co., Ltd.) with light of the measurement wavelength. Specifically, by inputting the average refractive index ((nx + ny + nz) / 3) and film thickness (d (μm)) into the AxoScan OPMF-1, the following can be calculated: Late axis direction (°) Re(λ) = R0(λ) Rth(λ) = ((nx + ny) / 2 - nz) × d Note that R0(λ) is displayed as a numerical value calculated by the AxoScan OPMF-1, but it means Re(λ).

[0011] [Optical Film] The optical film of the present invention comprises at least a substrate, an alignment film, and a liquid crystal layer 1. Due to the recent trend towards thinner polarizing plates, the thickness of the optical film of the present invention is preferably 45 μm or less, and more preferably 10 to 33 μm. In particular, the total thickness of the optical film is preferably 45 μm or less, and more preferably 10 to 33 μm. Here, the total thickness of the optical film refers to the total thickness from the surface of the substrate opposite to the side on which the alignment film is provided to the surface of the liquid crystal layer 1 opposite to the side on which the alignment film is provided. For example, if the optical film further includes a cured layer and has a structure of substrate / cured layer / alignment film / liquid crystal layer 1, the total thickness of the optical film is the thickness from the substrate including the cured layer to the liquid crystal layer 1.

[0012] From the viewpoint of polarizer durability, the optical film of the present invention preferably has a transmittance of 20% or less at a wavelength of 380 nm. The lower limit of the above transmittance is not particularly limited and may be 0% or 0.1% or more.

[0013] Each component forming this optical film will be described in detail below.

[0014] [Substrate] The optical film of the present invention includes a substrate. From the viewpoint of easily controlling the polarization state, the in-plane retardation Re(550) of the substrate at a wavelength of 550 nm is preferably 10 nm or less, more preferably 5 nm or less, and even more preferably 3 nm or less. The lower limit is not particularly limited, but 0 nm is an example. As the material forming the substrate, a polymer that is excellent in optical performance, transparency, mechanical strength, thermal stability, moisture shielding properties, and isotropy is preferred. The substrate is preferably transparent. Transparent means that the transmittance of visible light is 60% or more, preferably 80% or more, and more preferably 90% or more. Examples of polymer films that can be used as substrates include cellulose acylate films (e.g., cellulose triacetate film (refractive index 1.48), cellulose diacetate film, cellulose acetate butyrate film, and cellulose acetate propionate film), polyolefin films such as polyethylene and polypropylene, polyester resin films such as polyethylene terephthalate and polyethylene naphthalate, polyethersulfone films, polyacrylic resin films such as polymethyl methacrylate, polyurethane resin films, polyester films, polycarbonate films, polysulfone films, polyether films, polymethylpentene films, polyetherketone films, (meth)acrylonitrile films, and films of polymers having an alicyclic structure (norbornene resin (Arton: trade name, manufactured by JSR Corporation), and amorphous polyolefin (Zeonex: trade name, manufactured by Nippon Zeon Co., Ltd.)). Among these, triacetylcellulose, polyethylene terephthalate, or polymers having an alicyclic structure are preferred as materials for polymer films, and triacetylcellulose is more preferred from an optically isotropic viewpoint. In other words, a cellulose acylate film is preferred as the substrate, and a triacetylcellulose substrate is more preferred. To improve adhesion between the substrate and the layer provided thereon, the substrate may be subjected to surface treatment (e.g., glow discharge treatment, corona discharge treatment, ultraviolet (UV) treatment, and flame treatment).Further, an adhesive layer (undercoat layer) may be provided on the base material. Further, in order to impart slipperiness during the conveyance process to the base material or to prevent adhesion between the back surface and the front surface after winding, it is preferable to form a polymer layer on the surface of the base material by mixing inorganic particles having an average particle diameter of about 10 to 100 nm at a solid content mass ratio of 5 to 40%. Examples of the method for forming the polymer layer include a method of applying a composition for forming a polymer layer to one side of the base material and a method of co-casting the composition for forming a polymer layer on the base material. As the lower limit value of the film thickness of the base material, 5 μm or more is preferable, and 10 μm or more is more preferable. As the upper limit value of the film thickness, 80 μm or less is preferable, 45 μm or less is more preferable, and 25 μm or less is even more preferable. When the film thickness of the base material is 25 μm or less, it is preferable from the viewpoint of thinning the polarizing plate.

[0015] [Additives for the base material] Various additives (for example, optical anisotropy adjusters, wavelength dispersion adjusters, fine particles, plasticizers, ultraviolet absorbers, deterioration inhibitors, and release agents, etc.) can be added to the base material. Further, when the base material is a cellulose acetate film, the timing of addition may be any time in the dope preparation process (process for preparing a cellulose acetate solution), but a process of adding an additive at the end of the dope preparation process and then preparing may also be performed. The ultraviolet absorber (UV absorber) contributes to improving the durability of the polarizer. In particular, in the aspect where the base material is used as a surface protection film of a polarizing plate, the addition of a UV absorber is effective. There is no particular limitation on the UV absorber that can be used in the present invention. Any of the UV absorbers used in conventional base materials can be used. Examples of the UV absorber include the compounds described in JP-A-2006-184874. Polymer UV absorbers can also be preferably used, and particularly, the polymer type UV absorber described in JP-A-6-148430 is preferably used. The amount of the UV absorber used is not uniform depending on the type of the UV absorber, usage conditions, etc., but it is more preferable that the UV absorber is contained at a ratio of 1 to 3% by mass with respect to the main component. Examples of the UV absorber having the following structure are given below, but the UV absorber to be added is not limited thereto.

[0016]

[0017] [Alignment Film] The alignment film is preferably disposed on a substrate.

[0018] The alignment film is not particularly limited as long as it has a function of aligning liquid crystal compounds. Generally, the alignment film is mainly composed of a polymer. There are descriptions of many polymer materials for alignment films in a large number of documents, and a large number of commercially available products can be obtained. As the polymer material for the alignment film, polyvinyl alcohol, polyimide or derivatives thereof are preferred, and modified or unmodified polyvinyl alcohol is more preferred. The above-mentioned polymer materials for alignment films are known to be subjected to rubbing treatment by a known method and used as a rubbed alignment film. Examples of the alignment film include the alignment film described in WO2001 / 088574, pages 43, line 24 to page 49, line 8; the alignment film made of modified polyvinyl alcohol described in paragraphs

[0071] to

[0095] of Japanese Patent No. 3907735; and the liquid crystal alignment film formed by the liquid crystal aligning agent described in JP-A-2012-155308.

[0019] When forming the alignment film, it is preferable to use a photoalignment film as the alignment film because an object does not come into contact with the surface of the alignment film, and it is possible to prevent surface deterioration. Examples of the photoalignment film include an alignment film formed of a polymer material such as a polyamide compound and a polyimide compound described in paragraphs

[0024] to

[0043] of WO2005 / 096041; a liquid crystal alignment film formed by a liquid crystal aligning agent having a photoalignment group described in JP-A-2012-155308; and a product named LPP-JP265CP manufactured by Rolic Technologies.

[0020] The thickness of the alignment film is preferably 0.01 to 10 μm, more preferably 0.01 to 1 μm, and even more preferably 0.01 to 0.5 μm in terms of relaxing surface irregularities that may exist on the substrate and forming an optically anisotropic layer with a uniform film thickness.

[0021] (Photo-alignment film) As described above, the present invention may also use a photo-alignment film as the alignment film. A photo-alignment film is a photo-alignment film containing a compound having a photo-aligning group. A photo-aligning group is a group that has a photo-alignment function in which rearrangement or an anisotropic chemical reaction is induced by irradiation with anisotropic light (for example, plane-polarized light). From the viewpoint of excellent uniformity of orientation and good thermal and chemical stability, a photo-aligning group that undergoes at least one of dimerization and isomerization by the action of light is preferred.

[0022] Examples of photo-directing groups that dimerize upon the action of light include groups having the skeleton of at least one derivative selected from the group consisting of cinnamic acid derivatives, coumarin derivatives, chalcone derivatives, maleimide derivatives, and benzophenone derivatives. Examples of photo-directing groups that isomerize upon the action of light include groups having the skeleton of at least one compound selected from the group consisting of azobenzene compounds, stilbene compounds, spiropyran compounds, cinnamic acid compounds, and hydrazono-β-ketoester compounds.

[0023] The photo-directing group is preferably a group having the skeleton of at least one derivative selected from the group consisting of cinnamic acid derivatives, coumarin derivatives, chalcone derivatives, and maleimide derivatives, or a group having the skeleton of at least one compound selected from the group consisting of azobenzene compounds, stilbene compounds, and spiropyran compounds, and more preferably a cinnamoyl group.

[0024] Among compounds having photo-aligning groups, photo-aligning polymers having cinnamoyl groups are preferred because they are less affected by contact with the photo-aligning film. Furthermore, the above effect becomes more pronounced if the compound having photo-aligning groups also has crosslinking groups. The crosslinking group can be any group that crosslinks, but cationic polymerizable groups such as epoxy groups, or radical polymerizable groups such as acrylates and methacrylates are preferred. In other words, it is preferable for a compound having photo-aligning groups (especially the photo-aligning polymer described later) to have a photo-aligning group and at least one selected from radical polymerizable groups and cationic polymerizable groups. On the other hand, for adhesion improvement described later, it is even more preferable for a compound having photo-aligning groups to have both cationic polymerizable groups and radical polymerizable groups, as they can be used functionally separated, such as using cationic polymerizable groups for the hard film of the photo-aligning film and using radical polymerizable groups for adhesion improvement. In other words, it is preferable for a compound having photo-aligning groups (especially the photo-aligning polymer described later) to have a photo-aligning group, a radical polymerizable group, and a cationic polymerizable group.

[0025] The compound having a photo-orienting group is preferably a photo-orienting polymer comprising repeating unit A having a photo-orienting group and repeating unit B having a crosslinking group. Preferred embodiments of the photo-orienting polymer will be described in detail.

[0026] <Optical alignment polymer> The optical alignment polymer used in the present invention is preferably an optical alignment polymer containing a repeating unit A having an optical alignment group and a repeating unit B having a crosslinkable group. As the structure of the main chain of the repeating unit A and the repeating unit B, known structures can be mentioned. Examples of the structure of the main chain of the repeating unit A and the repeating unit B include a skeleton selected from the group consisting of (meth)acrylic, styrene, siloxane, cycloolefin, methylpentene, amide, and aromatic ester, a skeleton selected from the group consisting of (meth)acrylic, siloxane, and cycloolefin is more preferable, and a (meth)acrylic skeleton is even more preferable. That is, it is preferably an optical alignment polymer containing a repeating unit A having a cinnamoyl group having an acrylic skeleton and a repeating unit B having a crosslinkable group having an acrylic skeleton.

[0027] As the optical alignment polymer, a copolymer having a repeating unit A containing an optical alignment group represented by the following formula (A) and a repeating unit B containing a crosslinkable group represented by the following formula (B) is preferable.

[0028]

[0029] In the above formula (A), R １ represents a hydrogen atom or a methyl group. L １ represents a divalent linking group. R ２ , R ３ , R ４ , R ５ and R ６ each independently represent a hydrogen atom or a substituent, and among R ２ , R ３ , R [[ID= 28]] ４ , R ５ and R ６ , two adjacent groups may be bonded to form a ring. In the above formula (B), R ７ represents a hydrogen atom or a methyl group, L ２ represents a divalent linking group, and X represents a crosslinkable group.

[0030] L in the above formula (A) １The divalent linking group represented by will be explained. Examples of divalent linking groups include divalent hydrocarbon groups which may have substituents, divalent heterocyclic groups which may have substituents, -O-, -S-, -N(Q)-, -CO-, and groups which are combinations thereof. Q represents a hydrogen atom or substituent. Divalent hydrocarbon groups may be linear, branched, or cyclic. Examples of divalent hydrocarbon groups include divalent aliphatic hydrocarbon groups such as alkylene groups having 1 to 10 carbon atoms (preferably 1 to 5), alkenylene groups having 1 to 10 carbon atoms, and alkylene groups having 1 to 10 carbon atoms; divalent alicyclic hydrocarbon groups such as cycloalkane rings having 3 to 10 carbon atoms; and divalent aromatic hydrocarbon groups such as arylene groups. Examples of divalent heterocyclic groups include divalent aliphatic heterocyclic groups such as oxolane-diyl, oxane-diyl, piperidine-diyl, and piperazine-diyl; and divalent aromatic heterocyclic groups such as pyridylene (pyrididine-diyl), pyridazine-diyl, imidazole-diyl, thienylene (thiophene-diyl), and quinolylene (quinoline-diyl). The number of carbon atoms in the divalent heterocyclic group is preferably 1 to 12. Examples of groups combining these include groups combining at least two selected from the group consisting of the above-mentioned optionally substituted divalent hydrocarbon groups, optionally substituted divalent heterocyclic groups, -O-, -S-, -N(Q)- (where Q represents a hydrogen atom or substituent), and -CO-, specifically -(COO-divalent hydrocarbon group). ｐExamples include -O- (where p represents an integer of 1 or more), -CO-NH-divalent hydrocarbon group-O-, -COO-divalent hydrocarbon group-NH-, -COO-divalent heterocyclic group-, -CO-divalent heterocyclic group-, -COO-divalent hydrocarbon group-divalent heterocyclic group-, -CO-divalent heterocyclic group-divalent hydrocarbon group-O-, -CO-NH-divalent hydrocarbon group-divalent heterocyclic group-, -CO-divalent heterocyclic group-divalent hydrocarbon group-NH-, and -divalent hydrocarbon group-O-. Substituents that alkylene groups and arylene groups may have, as well as substituents represented by Q, include, for example, halogen atoms, alkyl groups, alkoxy groups, aryl groups, aryloxy groups, cyano groups, carboxyl groups, alkoxycarbonyl groups, and hydroxyl groups.

[0031] Next, in the above formula (A) R ２ , R ３ , R ４ , R ５ and R ６ The substituents represented by one aspect of the above formula (A) will be explained. ２ , R ３ , R ４ , R ５ and R ６ However, as mentioned above, it may be a hydrogen atom instead of a substituent.

[0032] In the above formula (A), R ２ , R ３ , R ４ , R ５ and R ６ The substituents represented in one embodiment are preferably, independently, a halogen atom, a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, a linear alkyl halide having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a cyano group, an amino group, or a group represented by the following formula (11), because the photo-aligning group interacts more easily with the liquid crystal compound, resulting in better liquid crystal alignment.

[0033]

[0034] Here, in formula (11) above, * represents the bond position with the benzene ring in formula (A) above, and R ９ This represents a monovalent organic group.

[0035] Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms.

[0036] Regarding the group represented by the above formula (11), R in the above formula (11) ９ Examples of monovalent organic groups represented by include linear or cyclic alkyl groups having 1 to 20 carbon atoms. Linear alkyl groups with 1 to 6 carbon atoms are preferred, specifically including methyl, ethyl, and n-propyl groups, with methyl or ethyl groups being preferred. Cyclic alkyl groups with 3 to 6 carbon atoms are preferred, specifically including cyclopropyl, cyclopentyl, and cyclohexyl groups, with cyclohexyl groups being preferred. Note that R in formula (11) above refers to... ９ The monovalent organic group represented by may be a combination of multiple linear alkyl groups and cyclic alkyl groups, either directly or via single bonds.

[0037] In the present invention, the photo-aligning group interacts more readily with the liquid crystal compound, resulting in better liquid crystal alignment. ２ , R ３ , R ４ , R ５ and R ６ Of these, at least R ４ It is preferable that R represents the substituents described above, and furthermore, the linearity of the resulting photo-oriented polymer is improved, it interacts more easily with the liquid crystal compound, and the liquid crystal orientation is further improved, ２ , R ３ , R ５ and R ６ It is more preferable that both represent hydrogen atoms.

[0038] In the present invention, the reaction efficiency is improved when the resulting photo-aligned film is irradiated with light, so R in formula (A) above is used. ４However, it is preferably an alkyl group, a halogenated alkyl group, or an alkoxy group, more preferably an alkoxy group, and particularly preferably an alkoxy group having 6 to 16 carbon atoms.

[0039] Next, L in formula (B) above ２ Let's explain the divalent linking group represented by .

[0040] As a divalent linking group, it is preferable that the photo-aligning group interacts more easily with the liquid crystal compound, resulting in better liquid crystal alignment. This is because the photo-aligning group interacts more readily with the liquid crystal compound, resulting in better liquid crystal alignment. Therefore, a divalent linking group is preferable that is a combination of at least two groups selected from the group consisting of linear groups having 1 to 18 carbon atoms (which may have substituents), branched or cyclic alkylene groups having 3 to 18 carbon atoms (which may have substituents), arylene groups having 6 to 12 carbon atoms (which may have substituents), ether groups (-O-), carbonyl groups (-C(=O)-), and imino groups (-NH-) (which may have substituents).

[0041] Examples of substituents that the alkylene group, arylene group, and imino group may have include halogen atoms, alkyl groups, alkoxy groups, aryl groups, aryloxy groups, cyano groups, carboxyl groups, alkoxycarbonyl groups, and hydroxyl groups. Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0042] Next, the crosslinkable group represented by X in formula (B) above will be explained. X (crosslinkable group) in formula (B) above can be any known crosslinkable group. Among these, cationic polymerizable groups or radical polymerizable groups are preferred due to their excellent adhesion to the upper layer.

[0043] Examples of cationic polymerizable groups include epoxy groups, epoxycyclohexyl groups, and oxetanyl groups.

[0044] Examples of radical polymerizable groups include acryloyl groups, methacryloyl groups, vinyl groups, styryl groups, and allyl groups.

[0045] In the present invention, it is preferable that the repeating unit B includes a repeating unit in which X in formula (B) is a crosslinkable group represented by a cationic polymerizable group (hereinafter also abbreviated as "repeating unit B1") and a repeating unit in which X in formula (B) is a crosslinkable group represented by a radical polymerizable group (hereinafter also abbreviated as "repeating unit B2"), for the reason that the strength of the optical film and laminate of the present invention, as described later, is increased.

[0046] Specific examples of repeating units A containing the photo-directing group represented by the above formula (A) include the following repeating units A-1 to A-44. In the following formula, Me represents a methyl group and Et represents an ethyl group. In the following specific examples, the "1,4-cyclohexyl group" contained in the divalent linking group of repeating units A-1 to A-10 may be either the cis or trans isomer, but the trans isomer is preferred.

[0047]

[0048]

[0049] On the other hand, specific examples of repeating units B-1 to B-17 shown below are repeating units B-1 to B-17 that include the crosslinkable group represented by the above formula (B).

[0050]

[0051] Furthermore, specific examples of repeating units B-18 to B-47 shown below are examples of repeating units B-18 to B-47 that include the crosslinkable group represented by the above formula (B).

[0052]

[0053] The photo-oriented polymer used in the present invention preferably satisfies the following formula (12) in mass ratio of the content a of the repeating unit A described above to the content b of the repeating unit B described above. It is more preferably satisfied by formula (13), even more preferably by formula (14), and particularly preferably by formula (15). 0.03 ≤ a / (a+b) ≤ 0.5 ... (12) 0.03 ≤ a / (a+b) ≤ 0.3 ... (13) 0.03 ≤ a / (a+b) ≤ 0.2 ... (14) 0.05 ≤ a / (a+b) ≤ 0.2 ... (15)

[0054] Furthermore, when the photo-aligning polymer used in the present invention has repeating units B2 as described above, along with the repeating unit B1, it is preferable that the mass ratio of the content a of repeating unit A, the content b1 of repeating unit B1, and the content b2 of repeating unit B2 satisfy the following formula (16), and more preferably the following formula (17). This is because it is possible to further increase the strength of the optically anisotropic layer including the photo-aligning film while maintaining good liquid crystal alignment and adhesion.

[0055] The photo-oriented polymer used in the present invention may have other repeating units in addition to the repeating units A and B described above, as long as they do not hinder the effects of the present invention. Examples of monomers (radical polymerizable monomers) that form such other repeating units include acrylic acid ester compounds, methacrylic acid ester compounds, maleimide compounds, acrylamide compounds, acrylonitrile, maleic anhydride, styrene compounds, and vinyl compounds.

[0056] The method for synthesizing the photo-oriented polymer used in the present invention is not particularly limited. For example, it can be synthesized by mixing a monomer that forms the repeating unit A described above, a monomer that forms the repeating unit B described above, and a monomer that forms any other repeating unit, and polymerizing them in an organic solvent using a radical polymerization initiator.

[0057] The weight-average molecular weight (Mw) of the photo-oriented polymer used in the present invention is preferably 10,000 to 500,000, and more preferably 30,000 to 300,000, for the reason that it further improves liquid crystal alignment.

[0058] The alignment film used in the present invention is preferably an alignment film having an average refractive index of 1.55 to 1.8 at a wavelength of 550 nm. More preferably, the average refractive index at a wavelength of 550 nm is 1.55 to 1.7 in order to reduce the refractive index difference with the anisotropic light absorption film, from the viewpoint of further improving anti-reflective performance.

[0059] Furthermore, the alignment film used in the present invention preferably has an in-plane refractive index anisotropy Δn at a wavelength of 550 nm of 0.05 to 0.45. It is more preferably 0.1 to 0.4, and even more preferably 0.1 to 0.3. By appropriately controlling the refractive index anisotropy of the alignment film, the anti-reflective function can be further improved.

[0060] In the present invention, the thickness of the alignment film is typically in the range of 10 to 10,000 nm, preferably 10 to 1,000 nm, and more preferably 10 to 300 nm. By appropriately controlling the thickness of the alignment film, interference can be utilized to further enhance the anti-reflective performance.

[0061] The photo-alignment film-forming composition may contain one or more other additives. For example, additives are added for the purpose of adjusting the refractive index of the photo-alignment film-forming composition. From the viewpoint of compatibility with compounds having photo-aligning groups, compounds having a hydrophilic group and a (meth)acryloyloxy group are preferred as additives. The above additives can be added in an amount that does not significantly reduce the alignment ability. Examples of the hydrophilic group include hydroxyl groups, carboxyl groups, sulfo groups, and amino groups.

[0062] The content of the photo-aligning compound (preferably a photo-aligning polymer) of the present invention in the photo-aligning film-forming composition of the present invention is not particularly limited, but when the photo-aligning film-forming composition contains an organic solvent as described later, it is preferably 0.1 to 50 parts by mass, and more preferably 0.5 to 10 parts by mass, per 100 parts by mass of the organic solvent. The content of the photo-aligning compound (preferably a photo-aligning polymer) is preferably 5 to 95% by mass, and more preferably 10 to 50% by mass, based on the total solid content of the photo-aligning film-forming composition.

[0063] The photo-alignment film-forming composition of the present invention preferably contains an organic solvent from the viewpoint of ease of workability in producing the photo-alignment film. Specifically, the organic solvent may include, for example, ketones (e.g., acetone, 2-butanone, methyl isobutyl ketone, cyclohexanone, and cyclopentanone), ethers (e.g., dioxane and tetrahydrofuran), aliphatic hydrocarbons (e.g., hexane), alicyclic hydrocarbons (e.g., cyclohexane), aromatic hydrocarbons (e.g., toluene, xylene, and trimethylbenzene), and halogenated carbons (e.g., dichloromethane, dichloroethane, dichlorobenzene, and chlorotoluene). Examples of suitable substances include esters (e.g., methyl acetate, ethyl acetate, and butyl acetate), water, alcohols (e.g., ethanol, isopropanol, butanol, and cyclohexanol), cellosolves (e.g., methyl cellosolve and ethyl cellosolve), cellosolve acetates, sulfoxides (e.g., dimethyl sulfoxide), and amides (e.g., dimethylformamide and dimethylacetamide). These may be used individually or in combination of two or more.

[0064] The photo-alignment film-forming composition of the present invention may contain other components besides those mentioned above, such as crosslinking catalysts, adhesion improvers, leveling agents, surfactants, and plasticizers.

[0065] Methods for applying an alignment film-forming composition (particularly a photo-alignment film-forming composition) onto a substrate include known methods such as spin coating, extrusion, gravure coating, die coating, bar coating, and applicator coating, as well as printing methods such as flexographic coating. When polarizers are manufactured using a continuous Roll-to-Roll manufacturing method, gravure coating, die coating, and printing methods such as flexographic coating are typically used as the coating method.

[0066] A photo-aligned film is manufactured by irradiating a film formed from the above materials with linearly polarized or unpolarized light. In this specification, "linearly polarized light irradiation" and "unpolarized light irradiation" refer to operations that cause a photoreaction in the photo-aligned material. The wavelength of light used varies depending on the photo-aligned material used and is not particularly limited as long as it is the wavelength necessary for the photoreaction. The peak wavelength of the light used for irradiation is preferably 200 to 700 nm, and ultraviolet light with a peak wavelength of 400 nm or less is more preferred.

[0067] Light sources used for light irradiation include commonly used light sources such as tungsten lamps, halogen lamps, xenon lamps, xenon flash lamps, mercury lamps, mercury xenon lamps, and carbon arc lamps; various lasers [e.g., semiconductor lasers, helium-neon lasers, argon ion lasers, helium-cadmium lasers, and YAG (yttrium aluminum garnet) lasers]; light-emitting diodes; and cathode ray tubes.

[0068] Methods for obtaining linearly polarized light include using polarizers (e.g., iodine polarizers, two-color dye polarizers, and wire grid polarizers), using prism-type elements (e.g., Grant-Thomson prisms) or reflective polarizers utilizing the Brewster angle, or using light emitted from a polarized laser light source. Alternatively, filters or wavelength conversion elements may be used to selectively irradiate only the light of the required wavelength.

[0069] When linearly polarized light is used, the light is irradiated from the top or back surface of the alignment layer, perpendicularly or obliquely to the surface of the alignment layer. The angle of incidence of the light varies depending on the photo-alignment material, but is preferably 0 to 90° (perpendicular), and more preferably 40 to 90°. When unpolarized light is used, the alignment layer is irradiated with unpolarized light from an oblique angle. The angle of incidence is preferably 10 to 80°, more preferably 20 to 60°, and even more preferably 30 to 50°. The irradiation time is preferably 1 to 60 minutes, and more preferably 1 to 10 minutes.

[0070] If patterning is required, a method can be employed in which light irradiation using a photomask is performed the number of times necessary to create the pattern, or a method can be employed in which the pattern is written by laser scanning.

[0071] (Epoxy Compound) Furthermore, the above-mentioned photo-alignment film-forming composition preferably contains an epoxy compound. Conventionally known epoxy compounds can be used. Here, the epoxy compound is preferably a compound having epoxy groups that do not fall under the category of the photo-aligning polymer described above, that is, a compound that has epoxy groups but does not have photo-aligning groups.

[0072] Examples of epoxy compounds include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, brominated bisphenol A type epoxy compounds, bisphenol S type epoxy compounds, diphenyl ether type epoxy compounds, hydroquinone type epoxy compounds, naphthalene type epoxy compounds, biphenyl type epoxy compounds, fluorene type epoxy compounds, phenol novolac type epoxy compounds, orthocresol novolac type epoxy compounds, trishydroxyphenylmethane type epoxy compounds, trifunctional epoxy compounds, tetraphenyloleethane type epoxy compounds, dicyclopentadienephenol type epoxy compounds, hydrogenated bisphenol A type epoxy compounds, bisphenol A kernel-containing polyol type epoxy compounds, polypropylene glycol type epoxy compounds, glycidyl ester type epoxy compounds, glycidylamine type epoxy compounds, glyoxal type epoxy compounds, alicyclic epoxy compounds, and heterocyclic epoxy compounds. Of these, alicyclic epoxy compounds are preferred. Here, an alicyclic epoxy compound refers to a compound having at least one alicyclic epoxy group. Furthermore, an alicyclic epoxy group refers to a monovalent substituent having a fused epoxy ring and a saturated hydrocarbon ring, preferably a monovalent substituent having a fused epoxy ring and a cycloalkane ring. More preferred alicyclic epoxy compounds include those having one or more structures in a single molecule in which an epoxy ring and a cyclohexane ring are fused.

[0073] In the present invention, the epoxy compound is preferably a polymer having repeating units containing epoxy groups (particularly alicyclic epoxy groups) in its side chains.

[0074] The molecular weight of the epoxy compound is preferably 1000 or more, because the photo-oriented polymer described above tends to be unevenly distributed on the surface of the photo-oriented film. Furthermore, the upper limit of the molecular weight of the epoxy compound is preferably 100,000 or less, from the viewpoint of ensuring solubility. In the present invention, the molecular weight of the epoxy compound is more preferably 2000 to 70,000 or less. Examples of epoxy compounds having such molecular weights include polymers having the repeating unit described above as repeating unit B1 of the photo-oriented polymer.

[0075] The epoxy compound content is preferably 60 to 98% by mass, and more preferably 70 to 90% by mass, relative to the total solid content of the photo-alignment film-forming composition.

[0076] The epoxy equivalent A of the epoxy compound is preferably 1000 or less, and more preferably 300 or less. Specifically, it is preferably 100 to 1000, more preferably 100 to 300, and even more preferably 150 to 250. The epoxy equivalent A can be expressed as A = Mw / n, where Mw is the molecular weight of the epoxy compound and n is the number of epoxy groups contained in one molecule of the epoxy compound.

[0077] [Liquid Crystal Layer 1] Liquid crystal layer 1 is an optically anisotropic layer formed by curing using a liquid crystal compound. The type of liquid crystal compound is not particularly limited. As liquid crystal layer 1, for example, an optically anisotropic layer obtained by forming a low-molecular-weight liquid crystal compound in a nematic orientation in a liquid crystal state and then fixing it by photocrosslinking or thermal crosslinking, and an optically anisotropic layer obtained by forming a polymer liquid crystal compound in a nematic orientation in a liquid crystal state and then fixing the orientation by cooling can be used. In this invention, the liquid crystal compound is a layer formed by fixing the liquid crystal compound by polymerization or the like, and it is no longer necessary for it to exhibit liquid crystal properties after it has become a layer. The liquid crystal compound is preferably a polymerizable liquid crystal compound. The polymerizable liquid crystal compound may be a polyfunctional polymerizable liquid crystal compound or a monofunctional polymerizable liquid crystal compound.

[0078] Generally, liquid crystal compounds can be classified into rod-shaped and disc-shaped types based on their shape. Furthermore, each type has low-molecular-weight and high-molecular-weight types. High-molecular-weight compounds generally refer to those with a degree of polymerization of 100 or more (Polymer Physics and Phase Transition Dynamics, by Masao Doi, p. 2, Iwanami Shoten, 1992). In the present invention, any type of liquid crystal compound can be used, but it is preferable to use rod-shaped liquid crystal compounds or disc-shaped liquid crystal compounds (discotic liquid crystal compounds). Two or more types of rod-shaped liquid crystal compounds, two or more types of disc-shaped liquid crystal compounds, or mixtures of rod-shaped and disc-shaped liquid crystal compounds may be used. It is more preferable to form the compounds using rod-shaped or disc-shaped liquid crystal compounds that have reactive groups, as this reduces the impact of temperature and humidity changes, and it is even more preferable that at least one of them has two or more reactive groups in one liquid crystal molecule. The liquid crystal compounds may also be a mixture of two or more types, in which case it is preferable that at least one of them has two or more reactive groups. As rod-shaped liquid crystal compounds, those described in Japanese Patent Publication No. 11-513019 and Japanese Patent Application Publication No. 2007-279688 can be preferably used, and as discotic liquid crystal compounds, those described in Japanese Patent Application Publication No. 2007-108732 and Japanese Patent Application Publication No. 2010-244038 can be preferably used, but are not limited to these. As liquid crystal compounds, inverse wavelength dispersive liquid crystal compounds (inverse dispersion compounds) may also be used. In this specification, when measuring the in-plane retardation (Re) value of a film made using a liquid crystal compound at a specific wavelength (visible light range), a liquid crystal compound in which the Re value becomes the same or higher as the measurement wavelength increases is called an inverse wavelength dispersive liquid crystal compound, and a liquid crystal compound in which the Re value decreases as the measurement wavelength increases is called a forward wavelength dispersive liquid crystal compound.

[0079] In the liquid crystal layer, the molecules of the liquid crystal compound may be fixed in one of the following orientation states: vertical orientation, horizontal orientation, hybrid orientation, or tilted orientation. To produce a phase difference plate with symmetrical viewing angle dependence, it is preferable that the disc surface of the discotic liquid crystal compound is substantially perpendicular to the film surface (liquid crystal layer surface), or that the long axis of the rod-shaped liquid crystal compound is substantially horizontal to the film surface (liquid crystal layer surface). A discotic liquid crystal compound being substantially perpendicular means that the average angle between the film surface (liquid crystal layer surface) and the disc surface of the discotic liquid crystal compound is in the range of 70 to 90°. In particular, the average angle is preferably 80 to 90°, and more preferably 85 to 90°. A rod-shaped liquid crystal compound being substantially horizontal means that the angle between the film surface (liquid crystal layer surface) and the director of the rod-shaped liquid crystal compound is in the range of 0 to 20°. In particular, the angle is preferably 0 to 10°, and more preferably 0 to 5°. The liquid crystal layer may be a layer in which liquid crystal compounds are immobilized in a torsion orientation with the thickness direction as the helical axis. For example, as disclosed in Japanese Patent No. 5753922, Japanese Patent No. 5960743, and International Publication No. 2021 / 033631, a liquid crystal layer may be provided which has a layer in which rod-shaped or disc-shaped liquid crystal compounds are immobilized in a torsion orientation with the thickness direction as the helical axis.

[0080] The liquid crystal layer may consist of only one layer, or it may be a laminate of two or more liquid crystal layers.

[0081] The liquid crystal layer can be formed by applying a coating solution containing liquid crystal compounds such as rod-shaped liquid crystal compounds and discotic liquid crystal compounds, and optionally other components such as polymerization initiators, orientation control agents, and other additives described later, onto an orientation film.

[0082] The in-plane retardation of the liquid crystal layer at a wavelength of 550 nm is preferably 70 to 143 nm. By setting it within this range, an image display device with a balanced transmittance and color can be provided when the display is observed with polarizing glasses. The upper limit of the in-plane retardation of the liquid crystal layer at a wavelength of 550 nm is preferably 143 nm or less, more preferably 135 nm or less, and even more preferably 130 nm or less. The lower limit of the in-plane retardation of the liquid crystal layer at a wavelength of 550 nm is preferably 70 nm or more, more preferably 75 nm or more, and even more preferably 80 nm or more. The thickness of the liquid crystal layer is preferably 8 μm or less, more preferably 5 μm or less, and even more preferably 0.3 to 3 μm.

[0083] [Hard Coat Layer] The optical film described in the present invention may have a hard coat layer on one or both of its surfaces. That is, the optical film may have a hard coat layer on the surface opposite to the surface on which the alignment film of the substrate is provided. By providing a hard coat layer, scratches during polarizing plate processing can be prevented. The hard coat layer is preferably formed from a compound that has radical polymerizable groups and polymerizes upon ultraviolet irradiation. Many known compounds can be used as such compounds. Furthermore, from the viewpoint of suppressing cracks due to elongation, it is also preferable to have a polymerizable compound that has hydrogen bonding groups. Such compounds are exemplified, for example, in International Publication No. 2022 / 209923. In addition, various additives (e.g., refractive index adjusters, leveling agents, lubricants, fine particles, UV inhibitors, and degradation inhibitors) can be added to the hard coat layer. By adjusting the refractive index, reflection from the surface in contact with the hard coat layer can be suppressed. Furthermore, by adding leveling agents and lubricants, a smooth and scratch-resistant optical film can be provided. From the viewpoint of preventing damage to the substrate during handling, it is preferable that the hard coat layer be provided on the side of the optical film substrate opposite to the side on which the alignment film is provided.

[0084] [Characteristics of the Optical Film] The in-plane retardation of the optical film at a wavelength of 550 nm is preferably 70 to 143 nm. By setting it within this range, an image display device with a balanced transmittance and color can be provided when the display is observed with polarizing glasses. The upper limit of the in-plane retardation of the liquid crystal layer at a wavelength of 550 nm is preferably 143 nm or less, more preferably 135 nm or less, and even more preferably 130 nm or less. The lower limit of the in-plane retardation of the liquid crystal layer at a wavelength of 550 nm is preferably 70 nm or more, more preferably 75 nm or more, and even more preferably 80 nm or more. Furthermore, it is preferable that the optical film exhibits inverse wavelength dispersion. Inverse wavelength dispersion refers to the property that when the in-plane retardation (Re) value of the optical film at a specific wavelength (visible light range) is measured, the Re value becomes the same or higher as the measured wavelength increases.

[0085] [Laminate] The laminate of the present invention includes the optical film and polarizer described above. The optical film is used together with the polarizer to solve the problem of blackout occurring when observing polarized sunglasses, as light emitted from the display passes through the polarizer and becomes linearly polarized. In addition, a liquid crystal layer (hereinafter sometimes referred to as liquid crystal layer 2) may be provided on the side of the polarizer opposite to the side on which the optical film is installed. For example, when used in an image display device in which the display is an OLED (Organic Light Emitting Diode), it is preferable that the liquid crystal layer 2 has a λ / 4 function. Having a λ / 4 function suppresses the reflection of ambient light on the OLED substrate, and good visibility can be obtained. Specifically, the λ / 4 function is a function that converts linearly polarized light of a certain wavelength to circularly polarized light (or circularly polarized light to linearly polarized light). The optical film and the polarizer, and the polarizer and the liquid crystal layer 2 can be bonded together via an adhesion layer. Examples of adhesion layers include known adhesive layers and adhesive layers. The polarizer constituting the laminate and the optionally included liquid crystal layer 2 are described below.

[0086] [Polarizer] The polarizer may be a conventionally known polarizer composed of a resin film containing a dichroic substance (for example, iodine as a component of the light-absorbing anisotropic film-forming composition described later, a dichroic dye, etc.) (for example, a polyvinyl alcohol (PVA)-based resin film, etc.). A polarizer made by adsorbing iodine or a dichroic dye onto polyvinyl alcohol and stretching it will be described. As a method for obtaining a polarizer by stretching and dyeing a laminated film in which a polyvinyl alcohol layer is formed on a substrate, examples include Japanese Patent No. 5048120, Japanese Patent No. 5143918, Japanese Patent No. 4691205, Japanese Patent No. 4751481, and Japanese Patent No. 4751486, and these known technologies relating to polarizers can also be preferably used. Examples of coated polarizers include those described in WO2018 / 124198, WO2018 / 186503, WO2019 / 132020, WO2019 / 132018, WO2019 / 189345, Japanese Patent Publication No. 2019-197168, Japanese Patent Publication No. 2019-194685, and Japanese Patent Publication No. 2019-139222, and known technologies related to these polarizers can also be preferably utilized.

[0087] In addition to the conventionally known polarizers described above, films formed by fixing the orientation state of a light-absorbing anisotropic film-forming composition containing a liquid crystal compound and a dichroic substance are also preferred, for the reason that they have better crack resistance. The components included in the light-absorbing anisotropic film-forming composition will be described below.

[0088] (Liquid Crystal Compound) The above-mentioned composition for forming an anisotropic light-absorbing film contains a liquid crystal compound. This allows for the orientation of dichroic substances to a higher degree of orientation while suppressing the deposition of dichroic substances. As the liquid crystal compound, either a polymer liquid crystal compound or a low-molecular-weight liquid crystal compound can be used, and a polymer liquid crystal compound is preferred because it can achieve a high degree of orientation. In addition, a polymer liquid crystal compound and a low-molecular-weight liquid crystal compound may be used in combination. Here, "polymer liquid crystal compound" refers to a liquid crystal compound that has repeating units in its chemical structure. Also, "low-molecular-weight liquid crystal compound" refers to a liquid crystal compound that does not have repeating units in its chemical structure. Examples of polymer liquid crystal compounds include the thermotropic liquid crystal polymer described in Japanese Patent Application Publication No. 2011-237513 and the polymer liquid crystal compounds described in paragraphs

[0012] to

[0042] of International Publication No. 2018 / 199096. Examples of low-molecular-weight liquid crystal compounds include those described in paragraphs

[0072] to

[0088] of Japanese Patent Application Publication No. 2013-228706, among which liquid crystal compounds exhibiting smectic properties are preferred. Examples of such liquid crystal compounds include those described in paragraphs

[0019] to

[0140] of International Publication No. 2022 / 014340, which are incorporated herein by reference. It is preferable that the liquid crystal compound is one that does not exhibit dichroism in the visible light region.

[0089] The above-mentioned composition for forming an anisotropic light-absorbing film may contain one or two liquid crystal compounds, but it is preferable to contain three or more liquid crystal compounds that satisfy the following condition, in order to make it easier to adjust the transmittance haze of the anisotropic light-absorbing film to 0.40% or less. Condition: The mass X of the liquid crystal compound with the largest content and the mass Y of the liquid crystal compound with the smallest content satisfy the following formula (2): X × 0.1 ≤ Y < X (2) In this invention, the above condition is satisfied if the content (mass) of three or more liquid crystal compounds is the same and represents the maximum value. Also, if the content (mass) of three or more liquid crystal compounds is the same and represents the minimum value, the above condition is satisfied if the composition further contains a liquid crystal compound with a mass X that satisfies the above formula (2), with the mass of any one of the liquid crystal compounds being Y. Also, if the content (mass) of two liquid crystal compounds is the same and represents the maximum value, the above condition is satisfied if the composition further contains a liquid crystal compound with a mass Y that satisfies the above formula (2), with the mass of any one of the liquid crystal compounds being X. Furthermore, if the content (mass) of the two liquid crystal compounds is the same and represents the minimum value, and the mass of one of the liquid crystal compounds is Y, and the mixture also contains a liquid crystal compound of mass X that satisfies formula (2) above, then the above conditions shall be met.

[0090] In the present invention, it is preferable that the LogP values ​​of three or more liquid crystal compounds satisfying the above conditions are all 5 or less, because it becomes easier to further adjust the transmittance haze of the light-absorbing anisotropic film to 0.40% or less, and the crack resistance is improved. Here, the logP value is an index that expresses the hydrophilic and hydrophobic properties of the chemical structure, and is sometimes called the hydrophilic-hydrophobic parameter. The logP value can be calculated using software such as ChemBioDraw Ultra or HSPiP (Ver. 4.1.07). It can also be determined experimentally by methods such as those in OECD Guidelines for the Testing of Chemicals, Sections 1, Test No. 117. In the present invention, unless otherwise specified, the value calculated by inputting the structural formula of the compound into HSPiP (Ver. 4.1.07) is adopted as the logP value.

[0091] Furthermore, in the present invention, it is preferable that three or more liquid crystal compounds satisfying the above conditions all have a biphenyl skeleton, as this makes it easier to further adjust the transmittance haze of the light-absorbing anisotropic film to 0.40% or less. Here, a biphenyl skeleton refers to a skeleton in which two phenyl groups (Ph) are single-bonded, and examples include a biphenyldiyl group (-Ph-Ph-).

[0092] Furthermore, in the present invention, it is preferable that at least one of the three or more liquid crystal compounds satisfying the above conditions is a polymer liquid crystal compound, as this makes it easier to further adjust the transmittance haze of the light-absorbing anisotropic film to 0.40% or less.

[0093] The liquid crystal compound content is preferably 25 to 2000 parts by mass, more preferably 100 to 1300 parts by mass, and even more preferably 200 to 900 parts by mass, relative to 100 parts by mass of the dichroic substance content described later. Having the liquid crystal compound content within the above range further improves the degree of orientation of the dichroic substance. If two or more liquid crystal compounds are included, the above-mentioned liquid crystal compound content refers to the total content of the liquid crystal compounds.

[0094] (Dichroic substance) The above-mentioned composition for forming anisotropic light-absorbing films contains a dichroic substance. Here, a dichroic substance refers to a dye whose absorbance differs depending on the direction. Furthermore, the dichroic substance may or may not exhibit liquid crystalline properties.

[0095] Dichroic materials are not particularly limited and include iodine, visible light absorbing materials (dichroic dyes), luminescent materials (fluorescent materials, phosphorescent materials), ultraviolet absorbing materials, infrared absorbing materials, nonlinear optical materials, carbon nanotubes, and inorganic materials (e.g., quantum rods). Conventionally known dichroic materials can be used. Specifically, for example, paragraphs

[0067] to

[0071] of JP 2013-228706, paragraphs

[0008] to

[0026] of JP 2013-227532, paragraphs

[0008] to

[0015] of JP 2013-209367, paragraphs

[0045] to

[0058] of JP 2013-14883, paragraphs

[0012] to

[0029] of JP 2013-109090, paragraphs

[0009] to

[0017] of JP 2013-101328, JP 20 Paragraphs

[0051] to

[0065] of Japanese Patent Publication No. 13-37353, paragraphs

[0049] to

[0073] of Japanese Patent Publication No. 2012-63387, paragraphs

[0016] to

[0018] of Japanese Patent Publication No. Hei 11-305036, paragraphs

[0009] to

[0011] of Japanese Patent Publication No. 2001-133630, paragraphs

[0030] to

[0169] of Japanese Patent Publication No. 2011-215337, paragraphs

[0021] to

[0075] of Japanese Patent Publication No. 2010-106242, paragraph

[0011] of Japanese Patent Publication No. 2010-215846 Paragraphs

[0025] to

[0025] of JP 2011-048311, paragraphs

[0017] to

[0069] of JP 2011-213610, paragraphs

[0013] to

[0133] of JP 2011-237513, paragraphs

[0074] to

[0246] of JP 2016-006502, paragraphs

[0005] to

[0051] of JP 2018-053167, paragraphs

[0014] to

[0032] of JP 2020-11716, International Publication Paragraphs

[0005] to

[0041] of Publication No. 2016 / 060173, paragraphs

[0008] to

[0062] of International Publication No. 2016 / 136561, paragraphs

[0014] to

[0033] of International Publication No. 2017 / 154835, paragraphs

[0014] to

[0033] of International Publication No. 2017 / 154695, paragraphs

[0013] to

[0037] of International Publication No. 2017 / 195833, paragraphs

[0014] to

[0034] of International Publication No. 2018 / 164252,Examples include paragraphs

[0021] to

[0030] of International Publication No. 2018 / 186503, paragraphs

[0043] to

[0063] of International Publication No. 2019 / 189345, paragraphs

[0043] to

[0085] of International Publication No. 2019 / 225468, paragraphs

[0050] to

[0074] of International Publication No. 2020 / 004106, and paragraphs

[0015] to

[0038] of International Publication No. 2021 / 044843.

[0096] Dichroic azo dye compounds are preferred as the dichroic substance. Dichroic azo dye compounds refer to azo dye compounds whose absorbance differs depending on the direction. Dichroic azo dye compounds may or may not exhibit liquid crystalline properties. If a dichroic azo dye compound exhibits liquid crystalline properties, it may exhibit either nematic or smectic properties. The temperature range in which the liquid crystalline phase is exhibited is preferably room temperature (about 20 to 28°C) to 300°C, and more preferably 50 to 200°C from the viewpoint of handling and manufacture suitability.

[0097] In the present invention, from the viewpoint of color adjustment, it is preferable to use a mixture containing, as a dichroic substance, a dye compound having a maximum absorption wavelength in the range of 380 nm to less than 455 nm (particularly a dichroic azo dye compound), a dye compound having a maximum absorption wavelength in the range of 455 nm to less than 560 nm (particularly a dichroic azo dye compound), and a dye compound having a maximum absorption wavelength in the range of 560 nm to 700 nm (particularly a dichroic azo dye compound).

[0098] The angle between the slow axis of the optical film of the present invention and the absorption axis of the polarizer is preferably 30 to 60°, and more preferably 35 to 50°. By controlling the angle, sufficient brightness can be obtained and color fringing can be reduced even when observing the display through polarized sunglasses.

[0099] Furthermore, it is preferable that the optical film of the present invention has the liquid crystal layer 1 side facing the polarizing plate side. This prevents scratches on the liquid crystal layer 1 after lamination to the polarizing plate. In addition, the light resistance of the liquid crystal layer 1 can be improved by adding a UV absorber to the support or hard coat layer.

[0100] [Liquid Crystal Layer 2] Preferably, the liquid crystal layer 2 has λ / 4 functionality. The constituent material of the liquid crystal layer 2 having λ / 4 functionality is not particularly limited, and it is a layer formed from a composition containing a liquid crystal compound, exhibiting optical anisotropy expressed by the orientation of the molecules of the liquid crystal compound. By providing it on the side opposite to the viewing side of the polarizer, an anti-reflective function can be provided. The liquid crystal layer 2 having λ / 4 functionality may be formed using a liquid crystal compound. The type of liquid crystal compound is not particularly limited, and various liquid crystal compounds exemplified in the liquid crystal layer 1 above can be used. As the liquid crystal compound, an inverse wavelength dispersive liquid crystal compound (inverse dispersive compound) may be used. The liquid crystal layer 2 having λ / 4 functionality may be a single liquid crystal layer or composed of two or more liquid crystal layers. For example, liquid crystal layers exemplified in International Publication No. 2019 / 022156, International Publication No. 2022 / 045187, and International Publication No. 2024 / 242041 may be used. When the liquid crystal layer 2 is formed from multiple liquid crystal layers, methods for forming each of the multiple liquid crystal layers by a coating method, a method for directly bonding the multiple liquid crystal layers by plasma treatment, and a method for bonding the multiple liquid crystal layers via an adhesive layer can be used. Known adhesive layers and bonding agents can be used as the adhesive layer.

[0101] One embodiment in which the liquid crystal layer is formed from multiple liquid crystal layers is one in which liquid crystal layer 2 includes a liquid crystal layer that is a λ / 2 plate and a liquid crystal layer that is a λ / 4 plate. A λ / 4 plate is a plate that has the function of converting linearly polarized light of a certain wavelength to circularly polarized light (or circularly polarized light to linearly polarized light). More specifically, it is a plate in which the in-plane retardation Re at a predetermined wavelength λnm is λ / 4 (or an odd multiple thereof). The in-plane retardation (Re(550)) of the λ / 4 plate at a wavelength of 550 nm may have an error of about 25 nm, centered on the ideal value (137.5 nm), and is preferably 110 to 160 nm, and more preferably 120 to 150 nm. A λ / 2 plate is an optically anisotropic film in which the in-plane retardation Re(λ) at a specific wavelength λnm satisfies Re(λ) ≈ λ / 2. This equation only needs to be achieved at any wavelength in the visible light region (for example, 550 nm). In particular, it is preferable that the in-plane retardation Re(550) at a wavelength of 550 nm satisfies the following relationship: 210 nm ≤ Re(550) ≤ 300 nm. The angle between the in-plane slow axis of the λ / 2 plate and the in-plane slow axis of the λ / 4 plate is not particularly limited, but 60 ± 20° is preferred.

[0102] Another embodiment in which the liquid crystal layer is formed from multiple liquid crystal layers includes a layer 1 with a vertically oriented disc-shaped liquid crystal compound fixed thereon, an optically anisotropic layer 2 with a torsionally oriented rod-shaped liquid crystal compound fixed thereon with the thickness direction as the helical axis, and a layer 3 with a vertically oriented rod-shaped liquid crystal compound fixed thereon. The in-plane retardation of layer 1 at a wavelength of 550 nm is preferably 140 to 220 nm. The product Δnd of the refractive index anisotropy Δn of layer 2 and the thickness d of layer 2, measured at a wavelength of 550 nm, is preferably 140 to 220 nm. Note that refractive index anisotropy Δn refers to the refractive index anisotropy of the optically anisotropic layer. The above Δnd is measured using an AxoScan (polarimeter) device from Axometrics Inc. and its device analysis software. The torsion angle of the liquid crystal compound in layer 2 (torsion angle in the orientation direction of the liquid crystal compound) is preferably 90 ± 30° (within the range of 60 to 120°). The in-plane retardation of layer 3 at a wavelength of 550 nm is preferably 0 to 10 nm. The retardation in the thickness direction of layer 3 at a wavelength of 550 nm is preferably -140 to -20 nm. The angle between the in-plane slow axis of layer 1 and the absorption axis of the polarizer is preferably 40 to 85°. The in-plane slow axis of layer 1 and the in-plane slow axis of layer 2 on the layer 1 side are preferably parallel.

[0103] Furthermore, in another embodiment in which the liquid crystal layer is formed from multiple liquid crystal layers, it may include a positive A plate and a positive C plate. The in-plane retardation of the positive A plate at a wavelength of 550 nm is preferably 100 to 180 nm. The retardation in the thickness direction of the positive C plate at a wavelength of 550 nm is preferably -140 to -20 nm. When the refractive index in the in-plane slow axis direction (the direction in which the refractive index in the plane is maximum) of the film is nx, the refractive index in the direction perpendicular to the in-plane slow axis is ny, and the refractive index in the thickness direction is nz, the positive A plate satisfies the relationship given by equation (A1). Note that the positive A plate exhibits a positive value for Rth. Equation (A1) nx > ny ≈ nz Note that the above "≈" includes not only the case where the two are completely identical, but also the case where the two are substantially identical. "Substantially identical" means, for example, that (ny - nz) × d (where d is the film thickness) is between -10 and 10 nm, preferably between -5 and 5 nm, which is included in "ny ≈ nz". A positive C plate satisfies the relationship in equation (C1). Note that a positive C plate shows a negative value for Rth. Equation (C1) nz > nx ≈ ny Note that the above "≈" includes not only cases where the two are completely identical, but also cases where the two are substantially identical. "Substantially identical" means, for example, that (nx - ny) × d (where d is the film thickness) is between 0 and 10 nm, preferably between 0 and 5 nm, which is included in "nx ≈ ny".

[0104] When the liquid crystal layer 2 has λ / 4 functionality, the in-plane retardation Re(550) at a wavelength of 550 nm is preferably 100 to 180 nm, more preferably 120 to 160 nm, and even more preferably 130 to 150 nm. It is also preferable that Re(450) / Re(550) < 1.0. The thickness of the liquid crystal layer 2 is preferably 10 μm or less, more preferably 5 μm or less, and even more preferably 0.3 to 3 μm. When the liquid crystal layer 2 has multiple layers, the total thickness of the multiple layers is preferably 15 μm or less, more preferably 10 μm or less, and even more preferably 0.5 to 6 μm.

[0105] The above-described laminate can be applied to an image display element. More specifically, an image display device can be obtained by placing the above-described laminate on an image display element. When the image of the obtained image display device is viewed through polarized sunglasses, the field of view is bright without blackout. Known image display elements can be used as the above-described image display element. Examples of image display elements include organic electroluminescent display elements and liquid crystal display elements.

[0106] [Example 1] [Preparation of Cellulose Acylate Film 1 Substrate] <Preparation of Core Layer Cellulose Acylate Dope> The following composition was placed in a mixing tank and stirred to dissolve each component, and a cellulose acetate solution to be used as the core layer cellulose acylate dope was prepared. -------------------------------------------------- Core layer cellulose acylate dope -------------------------------------------------- 100 parts by mass of cellulose acetate with an acetyl substitution degree of 2.88 15 parts by mass of plasticizer described in the examples of Japanese Patent Application Publication No. 2014-167577 430 parts by mass of methylene chloride (first solvent) 64 parts by mass of methanol (second solvent) -------------------------------------------------- <Preparation of outer layer cellulose acylate dope> 10 parts by mass of the following mat agent solution was added to 90 parts by mass of the above core layer cellulose acylate dope to prepare a cellulose acetate solution to be used as the outer layer cellulose acylate dope. -------------------------------------------------- Mat Solution -------------------------------------------------- ・Silica particles with an average particle size of 20 nm (AEROSIL R972, manufactured by Nippon Aerosil Co., Ltd.) 2 parts by mass ・Methylene chloride (first solvent) 76 parts by mass ・Methanol (second solvent) 11 parts by mass ・Cellulose acylate dope for the above core layer 1 part by mass --------------------------------------------------

[0107] The core layer cellulose acylate dope and the outer layer cellulose acylate dope were filtered using filter paper with an average pore size of 34 μm and a sintered metal filter with an average pore size of 10 μm. Then, the core layer cellulose acylate dope and the outer layer cellulose acylate dope on both sides were simultaneously cast into a drum at 20°C from the casting port (band casting machine). The film was peeled from the drum when the solvent content in the film was approximately 20% by mass, and both ends of the film in the width direction were fixed with tenter clips. The film was then dried while being stretched transversely at a stretching ratio of 1.15 times. After that, the obtained film was further dried by being transported between rolls in a heat treatment device to produce an optical film with a thickness of 25 μm, which was designated as cellulose acylate film 1. The in-plane retardation of the obtained cellulose acylate film 1 at a wavelength of 550 nm was 1 nm or less. The obtained cellulose acylate film 1 was used as a substrate. Cellulose acylate film 1 is a triacetylcellulose substrate.

[0108] [Formation of the alignment film] The alignment film forming coating liquid PA1, described later, was continuously applied onto the cellulose acylate film 1 using a wire bar. The substrate on which the coating film was formed was heated with 134°C hot air for 75 seconds. Next, the cured film was irradiated with ultraviolet light (10 mJ / cm²) through a wire grid polarizer. ２ A photo-alignment film PA-1 was formed using a light source (ultra-high pressure mercury lamp, measurement wavelength 313 nm). At this time, the transmission axis of the wire grid polarizer was set at a 45° clockwise angle with respect to the longitudinal direction of the film. The film thickness of the photo-alignment film PA-1 was 0.5 μm.

[0109] ------------------------------------------------------------------- (Coating solution PA1 for orientation film formation) ------------------------------------------------------------------- Polymer PA-1 140.7 parts by mass 38.7% butyl acetate solution of Polymer EP-1 1090.8 parts by mass Thermal acid generator B 33.8 parts by mass Diisopropyl ethylamine 3.4 parts by mass Methyl isobutyl ketone 1496.0 parts by mass Butyl acetate 2235.3 parts by mass -------------------------------------------------------------------

[0110] Polymer PA-1 (In the formula, the numerical values ​​listed for each repeating unit represent the content (mass%) of each repeating unit relative to the total number of repeating units. Weight-average molecular weight: 32000)

[0111]

[0112] Polymer EP-1 (weight-average molecular weight 45,000, epoxy equivalent: 209) (In the formula, the numerical values ​​listed for each repeating unit represent the content (mass%) of each repeating unit relative to the total number of repeating units.)

[0113]

[0114] Thermal acid generator B

[0115]

[0116] [Formation of Liquid Crystal Layer] A liquid crystal layer forming solution LC1 with the following composition was continuously applied to the above-mentioned photo-alignment film PA-1 using a wire bar. To dry the solvent of the coating solution and mature the alignment of the rod-shaped liquid crystal compound, the coating on the alignment film was heated with 70°C hot air for 90 seconds, and UV irradiation was performed at 70°C under conditions of an oxygen concentration of 100 ppm (parts per million) or less to fix the orientation of the liquid crystal compound, form a liquid crystal layer, and obtain optical film 1. The thickness of the liquid crystal layer was 0.9 μm. The angle of the slow axis was 45° counterclockwise with respect to the longitudinal direction. The in-plane retardation Re(550) at 550 nm was 100 nm, indicating forward wavelength dispersion.

[0117] --------------------------------------------------------------------------- (Coating solution LC1 for liquid crystal layer formation) --------------------------------------------------------------------------- Rod-shaped liquid crystal compound LC1-1 940 parts by mass Rod-shaped liquid crystal compound LC1-2 403 parts by mass Ethylene oxide-modified trimethylolpropane triacrylate (V#360, manufactured by Osaka Organic Chemical Co., Ltd.) 53.7 parts by mass Photopolymerization initiator Irgacure 819 (manufactured by BASF) 40.3 parts by mass 14.5% solution of cyclopentanone of leveling agent KA1 23.1 parts by mass Ethyl propionate 1780 parts by mass Methyl isobutyl ketone 1760 parts by mass ---------------------------------------------------------------------------

[0118] Rod-shaped liquid crystal compound LC1-1

[0119]

[0120] Rod-shaped liquid crystal compound LC1-2

[0121]

[0122] Leveling agent KA1 (In the formula below, a, b, and c represent the content (mass%) of each repeating unit relative to the total number of repeating units, where a is 56% by mass, b is 36% by mass, and c is 8% by mass. The weight-average molecular weight was 17,000.)

[0123]

[0124] [Example 2] An optical film 2 was obtained in the same manner as in Example 1, except that cellulose acylate film 1 was replaced with cellulose acylate film TJ25 (manufactured by Fujifilm Corporation: thickness 25 μm).

[0125] [Example 3] [Formation of Hard Coat Layer] The cellulose acylate substrate surface of the optical film 2 obtained in Example 2, opposite to the surface where the liquid crystal layer is formed, was continuously coated with the following hard coat layer forming composition HC1 using a wire bar. Then, after drying at 120°C for 5 minutes, an air-cooled mercury lamp was used to irradiate the film at 25°C and an oxygen concentration of 100 ppm (parts per million) or less, with an irradiation dose of 300 mJ / cm². ２ The optical film 3 was obtained by irradiating it with ultraviolet light. The thickness of the hard coat layer was 3 μm. --------------------------------------------------- (Coating solution HC1 for forming the hard coat layer) --------------------------------------------------- Polymerizable compound HC1 below 1707.1 parts by mass Polyfunctional acrylate A-TMMT (manufactured by Shin Nakamura Chemical Industry Co., Ltd.) 526.9 parts by mass Photopolymerization initiator Irgacure 127 (manufactured by BASF) 105.4 parts by mass Photopolymerization initiator Irgacure 819 (manufactured by BASF) 26.3 parts by mass RS-90 (manufactured by DIC Corporation, solid content concentration 10% by mass) 26.3 parts by mass Methyl isobutyl ketone 2634.4 parts by mass ---------------------------------------------------

[0126] Polymerizable compound HC1

[0127]

[0128] [Example 4] (Alkali saponification treatment) After raising the surface temperature of the cellulose acylate film 1 to 40°C, an alkaline solution with the composition shown below was applied to the band surface of the film using a bar coater at a rate of 14 ml / m². ２ The film was coated and heated to 110°C. The heated cellulose acylate film 1 was transported for 10 seconds under a steam-type far-infrared heater manufactured by Noritake Co., Limited. Subsequently, using a bar coater, 3 ml / m of pure water was applied to the cellulose acylate film 1. ２ The film was then applied. Next, the cellulose acylate film 1 was washed with water using a fountain coater and dried with an air knife three times, and then transported to a 70°C drying zone for 10 seconds to dry, thereby producing an alkaline saponification-treated cellulose acylate film.

[0129] --------------------------------------------------- (Alkaline solution) --------------------------------------------------- Potassium hydroxide 4.7 parts by mass Water 15.8 parts by mass Isopropanol 63.7 parts by mass Surfactant SF-1:C １４ H ２９ O(CH ２ CH ２ O) ２０ H 1.0 parts by mass Propylene glycol 14.8 parts by mass -------------------------------------------------------------------

[0130] [Formation of Orientation Film] An orientation film-forming composition with the following composition was continuously applied to the surface of the cellulose acylate film that had undergone alkali saponification treatment using a #14 wire bar. The resulting coated film was dried with hot air at 60°C for 60 seconds, and then with hot air at 100°C for 120 seconds to obtain an orientation film (thickness: 0.9 μm).

[0131] ------------------------------------------------------------------- (Composition for forming an oriented film) ------------------------------------------------------------------- Modified polyvinyl alcohol-1 below 100 parts by mass Sodium dodecyl sulfate 1.0 part by mass Photopolymerization initiator Irgacure 2959 (manufactured by BASF) 7.5 parts by mass Compound 1 below 1.75 parts by mass Water 2620 parts by mass Methanol 873 parts by mass -------------------------------------------------------------------

[0132] Modified Polyvinyl Alcohol-1 [In the formula below, the numerical values ​​listed for each repeating unit represent the content (mol%) of each repeat relative to the total number of repeating units.]

[0133]

[0134] Compound 1 (Et represents an ethyl group)

[0135]

[0136] [Formation of Optical Anisotropic Layer] The alignment film prepared above was continuously subjected to rubbing. At this time, the longitudinal direction of the long film and the transport direction were parallel, and the rotation axis of the rubbing roller was set to 45° clockwise with respect to the longitudinal direction of the film (transport direction). Next, a liquid crystal layer was formed in the same manner as in Example 1 to obtain optical film 4.

[0137] [Example 5] In Example 1, the amount of liquid crystal layer applied was adjusted to obtain an optical film 5 with an in-plane retardation of 70 nm at a wavelength of 550 nm.

[0138] [Example 6] In Example 1, the amount of liquid crystal layer applied was adjusted to obtain an optical film 6 with an in-plane retardation of 130 nm at a wavelength of 550 nm.

[0139] [Example 7] [Formation of Liquid Crystal Layer] The following composition LC2 was continuously coated onto the photo-alignment film PA-1 described in Example 1 using a wire bar. The coating formed on the photo-alignment film was heated to 120°C with hot air, then cooled to 60°C, and then heated at a wavelength of 365 nm and a pressure of 100 mJ / cm using a high-pressure mercury lamp under a nitrogen atmosphere. ２ The coating is irradiated with ultraviolet light, followed by heating to 120°C while applying 500 mJ / cm² of UV light. ２ An optical film 7 was obtained by irradiating the coating with ultraviolet light to form a liquid crystal layer. The thickness of the liquid crystal layer was 2.1 μm. The angle of the slow axis was 45° counterclockwise with respect to the longitudinal direction. The in-plane retardation at a wavelength of 550 nm was 100 nm, indicating inverse wavelength dispersion. The Re(450) / Re(550) ratio was 0.82.

[0140] --------------------------------------------------------------------------- (Composition LC2) --------------------------------------------------------------------------- The following rod-shaped liquid crystal compound LC1-3 30.0 parts by mass The following rod-shaped liquid crystal compound LC1-4 30.0 parts by mass The following rod-shaped liquid crystal compound LC1-5 27.0 parts by mass The above rod-shaped liquid crystal compound LC1-1 8.0 parts by mass The following rod-shaped liquid crystal compound LC1-6 5.0 parts by mass The following polymerization initiator PI1 0.50 parts by mass The above leveling agent KA1 14.5% cyclopentanone solution 0.06 parts by mass Cyclopentanone 181.0 parts by mass Methyl ethyl ketone 54.0 parts by mass ---------------------------------------------------------------------------

[0141] Rod-shaped liquid crystal compound LC1-3 (tBu represents a tert-butyl group)

[0142]

[0143] Rod-shaped liquid crystal compound LC1-4

[0144]

[0145] Rod-shaped liquid crystal compound LC1-5

[0146]

[0147] Rod-shaped liquid crystal compound LC1-6 (Me represents a methyl group)

[0148]

[0149] Polymerization initiator PI1

[0150]

[0151] [Example 8] An optical film 8 was obtained in the same manner as in Example 7, except that cellulose acylate film 1 was replaced with cellulose acylate film TJ25 (manufactured by Fujifilm Corporation: thickness 25 μm).

[0152] [Example 9] [Formation of Hard Coat Layer] The hard coat layer forming composition HC1 was continuously applied to the substrate surface of the optical film 8 obtained in Example 8, on the side opposite to the surface where the liquid crystal layer is formed, using a wire bar. Then, after drying at 120°C for 5 minutes, an air-cooled mercury lamp was used to irradiate the film at 25°C and an oxygen concentration of 100 ppm (parts per million) or less, with an irradiation dose of 300 mJ / cm². ２ The optical film 9 was obtained by irradiating it with ultraviolet light. The thickness of the hard coat layer was 3 μm.

[0153] [Example 10] In Example 8, the amount of composition LC2 applied was adjusted to create a liquid crystal layer with a thickness of 2.9 μm and an in-plane retardation of 141 nm at a wavelength of 550 nm. Subsequently, the hard coat layer forming composition HC1 was continuously applied to the cellulose acylate substrate surface opposite to the surface where the liquid crystal layer was formed using a wire bar. After drying at 120°C for 5 minutes, irradiation was performed using an air-cooled mercury lamp at 25°C and an oxygen concentration of 100 ppm (parts per million) or less, with an irradiation dose of 300 mJ / cm². ２ An optical film 10 was obtained by irradiating it with ultraviolet light. The thickness of the hard coat layer was 4 μm.

[0154] [Evaluation] [Measurement of optical film thickness] The thickness of the optical film was measured using a contact-type film thickness gauge.

[0155] [Measurement of liquid crystal layer thickness] The thickness of the liquid crystal layer was measured using a reflectance spectrometer FE3000 (manufactured by Otsuka Electronics Co., Ltd.).

[0156] [Absorption Measurement] The absorption characteristics of optical films 1 to 10 prepared in Examples 1 to 10 were measured using a spectrophotometer (UV-3150; manufactured by Shimadzu Corporation). The results are shown in Table 1. The transmittance in Table 1 represents the transmittance (%) at a wavelength of 380 nm.

[0157] [Preparation of Evaluation Panels] Optical films 1 to 10 prepared in Examples 1 to 10 were cut into 70 mm x 40 mm strips by rotating them counterclockwise by 45° along their longitudinal direction to obtain evaluation films. An evaluation panel was prepared by laminating the coated surface of the evaluation film onto a SAMSUNG GALAXY S24 equipped with an organic EL panel (organic EL display element) using a pressure-sensitive adhesive (SK2057, manufactured by Soken Chemical Co., Ltd.), aligning the longitudinal direction. Comparative Example 1 was prepared without laminating the optical film.

[0158] [Blackout Suppression Effect] The video source was displayed on the fabricated evaluation panel, and the panel was rotated around an axis perpendicular to the panel surface. The visibility of the display screen as seen through polarized sunglasses (compatible with polarized sunglasses) was observed from the front of the panel and evaluated according to the following criteria. Polarized sunglasses with a transmission axis in the vertical direction were used. A: The image is visible in all orientations. B: There is an orientation in which the display screen darkens, making the image difficult to see.

[0159] [Brightness] The prepared evaluation panel was used to display text with a white background and black text. The panel was rotated around an axis perpendicular to the panel surface, and observed from the front of the panel. The angle at which the panel appeared darkest was found using polarized sunglasses, and the brightness of the background portion of the screen at that angle was evaluated. Polarized sunglasses with a transmission axis in the vertical direction were used. In practical terms, A to D are preferable. A: Sufficiently bright B: Bright C: Somewhat dark D: Dark, but text is recognizable and there is no practical problem E: Very dark, text is not recognizable

[0160] In Table 1, the "Re" column represents the in-plane retardation at a wavelength of 550 nm for the optical film obtained in each example. In Table 1, the "Re(450) / Re(550)" column represents the ratio of the in-plane retardation at a wavelength of 450 nm to the in-plane retardation at a wavelength of 550 nm for the optical film.

[0161]

[0162] [Example 21] [Preparation of Polarizer] A roll of polyvinyl alcohol (PVA) film with a thickness of 60 μm was continuously stretched in the longitudinal direction in an iodine aqueous solution and dried to obtain a polarizer with a thickness of 13 μm. The luminous efficiency corrected single transmittance of the polarizer was 43%. At this time, the absorption axis direction and the longitudinal direction of the polarizer coincided. A cellulose acylate film TJ25 (manufactured by Fujifilm Corporation: thickness 25 μm) was bonded to one side of the above polarizer using the PVA adhesive described below to prepare a linear polarizer. (Preparation of PVA Adhesive) 100 parts by mass of a polyvinyl alcohol resin having an acetoacetyl group (average degree of polymerization: 1200, degree of saponification: 98.5 mol%, degree of acetoacetylation: 5 mol%) and 20 parts by mass of methylol melamine were dissolved in pure water at a temperature of 30°C, and the PVA adhesive was prepared as an aqueous solution adjusted to a solid content concentration of 3.7% by mass.

[0163] [Preparation of Double-Sided Polarizing Plate 1] The surface of the liquid crystal layer of the long optical film 1 prepared in Example 1 and the surface of the polarizer of the long linear polarizing plate prepared above (the side opposite to the cellulose acylate film TJ25) were continuously bonded together using a pressure-sensitive adhesive (SK2057, manufactured by Soken Chemical Co., Ltd.). Subsequently, the cellulose acylate film TJ25 bonded to the side opposite to the polarizer was peeled off to expose the polarizer, thereby preparing a single-sided polarizing plate 1. After bonding the exposed polarizer with a film having a cellulose acylate film, an alignment film A, and an optical anisotropy layer A as described in Example 1 of International Publication No. 2019 / 022156 using a pressure-sensitive adhesive (SK2057, manufactured by Soken Chemical Co., Ltd.), the cellulose acylate film and the alignment film A were peeled off to expose the optical anisotropy layer A. Furthermore, a pressure-sensitive adhesive (SK2057, manufactured by Soken Chemical Co., Ltd.) was used to bond a film having a cellulose acylate film, an alignment film A, and an optical anisotropy layer C as described in Example 25 of International Publication No. 2019 / 022156 to the surface of the optical anisotropy layer A. After this, the cellulose acylate film and the alignment film A were peeled off to expose the optical anisotropy layer C. A double-sided polarizing plate 1 was fabricated by the above procedure, in which the cellulose acylate film 1, the photo-alignment film PA-1, the liquid crystal layer, the linear polarizer, the optical anisotropy layer A (λ / 2 plate), and the optical anisotropy layer C (λ / 4 plate) were arranged in this order. Furthermore, when observed from the liquid crystal layer side, and with the transmission axis of the linear polarizer as the reference (0°), clockwise rotation is expressed as a positive value. The slow axis angle of the liquid crystal layer was +45°, the slow axis angle of optical anisotropy layer A (λ / 2 plate) was 72.5°, and the slow axis angle of optical anisotropy layer C (λ / 4 plate) was 12.5°.

[0164] [Example 22] Using a pressure-sensitive adhesive (SK2057, manufactured by Soken Chemical Co., Ltd.), the surface of the optical anisotropy layer (3a) of the optical film (3c-3b-3a) described in Example 3 of International Publication No. 2022 / 045187 was bonded to the exposed polarizer surface of the single-sided polarizing plate 1 prepared in Example 21. Subsequently, the cellulose acylate film on the optical anisotropy layer (3c) side was peeled off, exposing the surface of the optical anisotropy layer (3c) that was in contact with the cellulose acylate film. By following the above procedure, a double-sided polarizing plate 2 was prepared in which the cellulose acylate film 1, photoalignment film PA-1, liquid crystal layer, linear polarizer, optical anisotropy layer 3a, optical anisotropy layer 3b, and optical anisotropy layer 3c were arranged in this order. Furthermore, when observed from the cellulose acylate film 1 side, and with the absorption axis of the linear polarizer as the reference (0°), clockwise rotation is expressed as a positive value. The slow axis angle of the liquid crystal layer was +45°, and the slow axis angle of the optically anisotropic layer (3a) was -76°. In addition, the orientation axis angle of the liquid crystal compound on the optically anisotropic layer (3a) side of the optically anisotropic layer (3b) was -76°, which coincided with the slow axis direction of the optically anisotropic layer (3a).

[0165] [Example 23] [Preparation of Panel-side λ / 4 Plate] The above composition LC2 was coated onto the photo-alignment film E1 described in Comparative Example 1-1 of International Publication No. 2024 / 242041 using a bar coater. The coating formed on the photo-alignment film E1 was heated to 120°C with hot air, then cooled to 60°C, and then heated at a wavelength of 365 nm with a high-pressure mercury lamp at 100 mJ / cm² under a nitrogen atmosphere. ２ The coating is irradiated with ultraviolet light, followed by heating to 120°C while applying 500 mJ / cm² of UV light. ２By irradiating the coating with ultraviolet light, the orientation of the liquid crystal compound was fixed, and an optical film FIA having an optically anisotropic layer FIA was fabricated. The thickness of the optically anisotropic layer FIA was 2.9 μm, and Re(550) was 142 nm. Furthermore, the optically anisotropic layer FIA satisfied the relationship Re(450) ≤ Re(550) ≤ Re(650). Re(450) / Re(550) was 0.82. The optically anisotropic layer corresponds to a so-called λ / 4 plate. The surface of the optically anisotropic layer FIA of the above optical film FIA was bonded to the phase difference layer of the positive C plate FC-1 described in Comparative Example 1-1 of International Publication No. 2024 / 242041 using the UV adhesive 1 described therein, and the cellulose acylate film A1 on the optical film FIA side was peeled off to obtain the optical film FIAC. In Example 21, a pressure-sensitive adhesive (SK2057, manufactured by Soken Chemical Co., Ltd.) was used to bond the optical film FIA side of the optical film FIAC to the exposed polarizer surface of the single-sided polarizing plate 1, and the cellulose acylate film on the optical film FIAC side was peeled off. Following the above procedure, a double-sided polarizing plate 3 was fabricated in which the cellulose acylate film 1, photoalignment film PA-1, liquid crystal layer, linear polarizer, optical anisotropy layer FIA, and positive C plate FC-1 were arranged in this order. When observed from the cellulose acylate film 1 side, and with the absorption axis of the linear polarizer as the reference (0°), clockwise rotation was expressed as a positive value. The slow axis angle of the optical anisotropy layer 1 was +45°, and the slow axis angle of the optical anisotropy layer FIA was -45°.

[0166] [Example 24] A double-sided polarizing plate 4 was prepared in the same manner as in Example 23, except that the angle at which the optical film 1 was bonded was changed. Observing from the cellulose acylate film 1 side, and with the absorption axis of the linear polarizer as the reference (0°), clockwise rotation was expressed as a positive value. The slow axis angle of the liquid crystal layer was +30°, and the slow axis angle of the optical anisotropy layer FIA was -45°.

[0167] [Example 25] A double-sided polarizing plate 5 was prepared in the same manner as in Example 23, except that the bonding angle of the optical film 1 was changed. Observing from the cellulose acylate film 1 side, and with the absorption axis of the linear polarizer as the reference (0°), clockwise rotation was expressed as a positive value. The slow axis angle of the liquid crystal layer was +60°, and the slow axis angle of the optical anisotropy layer FIA was -45°.

[0168] [Example 26] A double-sided polarizing plate 6 was prepared in the same manner as in Example 23, except that the bonding surface of the optical film 1 was changed to the cellulose acylate film 1 side. Observing from the liquid crystal layer side, and with the absorption axis of the linear polarizer as the reference (0°), clockwise rotation was expressed as a positive value. The slow axis angle of the liquid crystal layer was -45°, and the slow axis angle of the optical anisotropy layer FIA was -45°.

[0169] [Example 27] An optical film CP1 was prepared by the method described in Example 1 of International Publication No. 2023 / 214502, comprising a cellulose acylate film A1 (substrate), a photoalignment film B1, a light absorption anisotropy layer C1, and a protective layer D1 adjacent to each other in this order. When the transmittance in the wavelength range of 280 to 780 nm was measured using a spectrophotometer, the average visible light transmittance of the optical film CP1 was found to be 42%, the absorption axis was parallel to the longitudinal direction, and it was confirmed that it functions as a polarizer. A pressure-sensitive adhesive (SK2057, manufactured by Soken Chemical Co., Ltd.) was used to bond the protective layer D1 side of the optical film CP1 to the cellulose acylate film 1 side of the optical anisotropy layer 1, and the cellulose acylate film A1 on the optical film CP1 side was peeled off to expose the photoalignment film B1, thereby preparing a single-sided polarizer 7. A pressure-sensitive adhesive (SK2057, manufactured by Soken Chemical Co., Ltd.) was used to bond the optical film FIA side of the optical film FIAC described in Example 23 to the exposed photo-alignment film B1 side of the single-sided polarizing plate 7, and the cellulose acylate film on the optical film FIAC side was peeled off. Following the above procedure, a double-sided polarizing plate 7 was fabricated in which the cellulose acylate film 1, photo-alignment film PA-1, liquid crystal layer, protective layer D1, light absorption anisotropy layer C1, photo-alignment film B1, optical anisotropy layer FIA, and positive C plate FC-1 were arranged in this order. When observed from the cellulose acylate film 1 side, and with the absorption axis of the light absorption anisotropy layer C1 as the reference (0°) and clockwise rotation as a positive value, the slow axis angle of the optical anisotropy layer 1 was +45°, and the slow axis angle of the optical anisotropy layer FIA was -45°.

[0170] [Example 28] A double-sided polarizing plate 8 was manufactured in the same manner as in Example 23, except that optical film 1 was replaced with optical film 9.

[0171] [Example 29] A double-sided polarizing plate 9 was manufactured in the same manner as in Example 22, except that optical film 1 was replaced with optical film 2.

[0172] [Example 30] A double-sided polarizing plate 10 was manufactured in the same manner as in Example 22, except that optical film 1 was replaced with optical film 3.

[0173] [Example 31] A double-sided polarizing plate 11 was manufactured in the same manner as in Example 22, except that optical film 1 was changed to optical film 4.

[0174] [Example 32] A double-sided polarizing plate 12 was manufactured in the same manner as in Example 22, except that optical film 1 was replaced with optical film 5.

[0175] [Example 33] A double-sided polarizing plate 13 was manufactured in the same manner as in Example 22, except that optical film 1 was replaced with optical film 6.

[0176] [Example 34] A double-sided polarizing plate 14 was manufactured in the same manner as in Example 22, except that optical film 1 was replaced with optical film 7.

[0177] [Example 35] A double-sided polarizing plate 15 was manufactured in the same manner as in Example 22, except that optical film 1 was replaced with optical film 8.

[0178] [Example 36] A double-sided polarizing plate 16 was manufactured in the same manner as in Example 22, except that optical film 1 was replaced with optical film 10.

[0179] [Comparative Example 21] A double-sided polarizing plate H1 was prepared in the same manner as in Example 21, except that optical film 1 was changed to cellulose acylate film TJ25 (25 μm, manufactured by Fujifilm).

[0180] [Evaluation] [Blackout] The double-sided polarizing plates 1 to 16 and H1 prepared in Examples 21 to 36 and Comparative Example 21 were cut into 70 mm x 40 mm strips, offset by 45° clockwise from the longitudinal direction, to obtain evaluation films. A SAMSUNG GALAXY S4 equipped with a commercially available organic EL panel (organic EL display element) was disassembled, the bonded polarizer and phase difference film were peeled off, and the prepared double-sided polarizing plates were bonded together using a pressure-sensitive adhesive (SK2057, manufactured by Soken Chemical Co., Ltd.) so that the optical films 1 to 10 or the cellulose acylate film TJ25 were on the opposite side from the organic EL display element, to prepare an evaluation panel, and the blackout suppression effect was evaluated using the method described above.

[0181] [Brightness] The prepared evaluation panel was used to display text with a white background and black text. The panel was rotated around an axis perpendicular to the panel surface, and observed from the front of the panel. The angle at which the panel appeared darkest was found using polarized sunglasses, and the brightness of the background portion of the screen at that angle was evaluated. Polarized sunglasses with a transmission axis in the vertical direction were used. In practical terms, A to D are preferable. A: Sufficiently bright B: Bright C: Somewhat dark D: Dark, but text is recognizable and there is no practical problem E: Very dark, text is not recognizable

[0182] In Table 2, the "Optical Film" column represents the type of optical film used in the double-sided polarizer of each embodiment. In Table 2, the "Liquid Crystal Layer 2" column represents the type of layer corresponding to liquid crystal layer 2 in the double-sided polarizer of each embodiment, where "1" represents a combination of optical anisotropy layer A (λ / 2 plate) and optical anisotropy layer C (λ / 4 plate), "2" represents a combination of optical anisotropy layer 3a, optical anisotropy layer 3b, and optical anisotropy layer 3c, and "3" represents a combination of optical anisotropy layer FIA and positive C plate FC-1. Note that all of the above embodiments "1" to "3" have λ / 4 functionality. In Table 2, the "Lagging Axis Angle (°)" column represents the angle (°) between the absorption axis of the polarizer in the double-sided polarizer of each embodiment and the in-plane lagging axis of the optical film. In Table 2, the "Re (nm)" column represents the in-plane retardation (nm) of the optical film in the double-sided polarizing plate of each example at a wavelength of 550 nm.

[0183]

[0184] As shown in Table 2, the desired effects were obtained when using the laminate of the present invention.

Claims

1. A laminate comprising an optical film, a polarizer, and a liquid crystal layer 2 in that order, wherein the optical film comprises a substrate, an alignment film, and a liquid crystal layer 1 in that order, and the in-plane retardation of the optical film at a wavelength of 550 nm is 70 to 143 nm.

2. The laminate according to claim 1, wherein the polarizer is arranged on the liquid crystal layer 1 side of the optical film.

3. The laminate according to claim 1, wherein the total thickness of the optical film is 45 μm or less.

4. The laminate according to claim 1, wherein the orientation film is obtained by curing a composition having a photo-orienting polymer having a photo-orienting group and at least one selected from a radical polymerizable group and a cationic polymerizable group.

5. The laminate according to claim 1, wherein the orientation film is obtained by curing a composition having a photo-orienting polymer having a photo-orienting group, a radical polymerizable group, and a cationic polymerizable group.

6. The laminate according to claim 4, wherein the orientation film is a photo-alignment film obtained by curing a photo-alignment film forming composition comprising the photo-aligning polymer and an epoxy compound, the content of the photo-aligning polymer is 10 to 50% by mass with respect to the total solid content of the photo-alignment film forming composition, and the epoxy equivalent A of the epoxy compound, represented by the following formula, is 300 or less. (Formula) A = Mw / n Mw represents the molecular weight of the epoxy compound, and n represents the number of epoxy groups contained in one molecule of the epoxy compound.

7. The laminate according to claim 1, wherein a hard coat layer is provided on the surface of the substrate opposite to the surface on which the orientation film is provided.

8. The laminate according to claim 1, wherein the transmittance of the optical film at a wavelength of 380 nm is 20% or less.

9. The optical film according to claim 1, wherein the substrate is a triacetylcellulose substrate.

10. The laminate according to claim 1, wherein the angle between the slow axis of the optical film and the absorption axis of the polarizer is 30 to 60 degrees.

11. The laminate according to claim 1, wherein the liquid crystal layer 2 is composed of one or more liquid crystal layers, and the liquid crystal layer 2 has a λ / 4 function.

Images