Polarizing plate protective film, polarizing plate including same, and liquid crystal display device

Abstract

Provided are a polarizing plate protective film, a polarizing plate including the same, and a liquid crystal display device, the polarizing plate protective film containing a light-absorbing layer including a resin and a dye that includes a quencher-incorporated dipyrromethene-based dye.

Description

Polarizer protective film, polarizer including the same, and liquid crystal display device

[0001] The present invention relates to a polarizing plate protective film, and a polarizing plate and a liquid crystal display device including the same.

[0002] Liquid crystal display devices, known as a type of image display device, are non-emissive devices that do not emit light from the liquid crystal panel itself that displays images. Therefore, liquid crystal display devices incorporate a backlight unit. This backlight unit is placed behind the liquid crystal panel and supplies light to the liquid crystal panel.

[0003] In white LED light-emitting devices that use white LEDs (light-emitting diodes) as the light source for their backlight units, various methods are known, including a method of producing white light by mixing blue light emitted from a blue LED with light emitted from a yellow phosphor, and a method of producing white light by mixing light emitted from blue, green, and red LEDs. However, these methods have a problem of a narrow color reproduction range compared to displays using organic light-emitting diodes (OLEDs). It has been found that this problem can be addressed by incorporating a dye with a specific absorption wavelength into the protective film of the polarizer used in liquid crystal display devices (a film that protects the polarizer, hereinafter referred to as the "polarizer protective film"). However, it is known that incorporating such a dye into the polarizer protective film reduces the polarization performance of the polarizer due to depolarization caused by fluorescence emitted by the dye, which is detrimental to achieving high contrast. It is also known that the dye is prone to degradation over time due to light exposure.

[0004] Dyes exhibiting excellent light resistance have been studied not only in polarizing filter protective films but also in optical filters. For example, Patent Document 1 describes an optical filter containing a catechol-coordinated dipyrromethene boron complex compound having a specific structure. Patent Document 1 also describes that the catechol-coordinated dipyrromethene boron complex compound selectively absorbs light in the wavelength range of 480 to 530 nm, is less likely to emit fluorescence that causes contrast reduction, and exhibits excellent light resistance. Furthermore, Patent Document 2 describes an optical film containing a dipyrromethene cobalt complex having a specific structure in which two dipyrromethene ligands are coordinated. Patent Document 2 describes that the dipyrromethene cobalt complex has a ΔG (a value calculated under specific conditions using the quantum chemistry calculation program Gaussian 16) of −1.0 kcal / mol or more before and after the reaction between the boron dipyrromethene of the dipyrromethene ligand and singlet oxygen, and that the dipyrromethene cobalt complex can selectively and efficiently absorb light with a wavelength of around 500 nm (external light and secondary emission from the light source of a display device), and further has excellent light resistance.

[0005] JP 2023-051753 A JP 2023-101372 A

[0006] The present inventors have studied polarizing plate protective films that use a dipyrromethene dye, and have found that the optical filter described in Patent Document 1 and the optical film described in Patent Document 2 both have poor light absorption tailing due to the specific structure of the dipyrromethene dye, and when applied to an image display device, they unnecessarily absorb display light from the liquid crystal display device. An object of the present invention is to provide a polarizing plate protective film that uses a dipyrromethene dye and has excellent absorption tailing and light fastness, a polarizing plate including this polarizing plate protective film, and a liquid crystal display device including this polarizing plate.

[0007] The above problems have been solved by the following means. <1> A polarizing plate protective film comprising a light-absorbing layer containing a resin and a dye including a quencher-containing dipyrromethene dye. <2> The polarizing plate protective film according to <1>, wherein the dye includes two or more dyes having different main absorption wavelength bands, with the proviso that at least one of the two or more dyes having different main absorption wavelength bands is the quencher-containing dipyrromethene dye. <3> The polarizing plate protective film according to <1> or <2>, wherein the quencher-containing dipyrromethene dye is represented by the following general formula (P): In the above formula, R １ ~R ６ represents a hydrogen atom or a substituent. ７ and R ８ represents a fluorine atom. ９ represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, or an electron-donating quencher moiety. １ ~R ６ and R ９ <4> The polarizing plate protective film according to <3>, wherein the electron-donating quencher moiety is a ferrocenyl group represented by the following general formula (2M), or an aryl group having at least one of an amino group, an alkoxy group, a hydroxy group, and a nitro group as a substituent: In the above formula, L represents a single bond or a divalent linking group that is not conjugated with the dipyrromethene dye in the quencher-containing dipyrromethene dye. １ｍ ~R ９ｍ each represents a hydrogen atom or a substituent. M is an atom that can constitute a metallocene compound, and represents Fe, Co, Ni, Ti, Cu, Zn, Zr, Cr, Mo, Os, Mn, Ru, Sn, Pd, Rh, V, or Pt. * represents a bonding site with the dipyrromethene dye in the quencher-incorporated dipyrromethene dye. <5> The above L is a single bond or an arylene group having 6 to 12 carbon atoms, and the above R １ｍ ~R ９ｍis a hydrogen atom, a halogen atom, an alkyl group, an acyl group, or an alkoxy group, and M is Fe. <6> A polarizing plate comprising the polarizing plate protective film according to any one of <1> to <5>. <7> A liquid crystal display device comprising the polarizing plate according to <6>. <8> The liquid crystal display device according to <7>, wherein the polarizing plate protective film is disposed between a liquid crystal cell and a polarizer.

[0008] In the present invention, when there are multiple substituents or linking groups, etc. (hereinafter referred to as substituents, etc.) represented by a specific symbol or formula, or when multiple substituents, etc. are specified simultaneously, unless otherwise specified, the respective substituents, etc. may be the same or different from each other. The same applies to the specification of the number of substituents, etc. Furthermore, when multiple substituents, etc. are adjacent (especially when they are adjacent), they may be linked to each other to form a ring, unless otherwise specified. Furthermore, unless otherwise specified, rings, such as alicyclic rings, aromatic rings, and heterocyclic rings, may be further condensed to form a condensed ring. In the present invention, unless otherwise specified, the light-absorbing layer may contain one or more of the components (dyes, resins, other components, etc.) constituting the light-absorbing layer. In the present invention, the polymer may be either a chain polymerization polymer or a condensation polymerization polymer, and may be either a homopolymer or a copolymer. Furthermore, if it is a copolymer, it may be either a random polymer, a block polymer, etc. In the present invention, unless otherwise specified, the double bond may be either E-type or Z-type in the molecule, or a mixture thereof. In the present invention, the term "compound" (including complexes) refers to the compound itself, its salts, and its ions. It also includes compounds with partially modified structures, provided that the effects of the present invention are not impaired. Furthermore, compounds that are not specified as substituted or unsubstituted may have any substituent, provided that the effects of the present invention are not impaired. This also applies to substituents and linking groups. In the present invention, a numerical range expressed using "to" refers to a range that includes the numerical values ​​before and after "to" as the lower and upper limits. In the present invention, a composition encompasses not only mixtures with constant component concentrations (i.e., uniformly dispersed components), but also mixtures with component concentrations that vary within a range that does not impair the intended function. In the present invention, "having a main absorption wavelength band in the wavelength range XX to YY nm" means that the wavelength showing maximum absorption (i.e., the maximum absorption wavelength) is present in the wavelength range XX to YY nm.Therefore, as long as this absorption maximum wavelength is within the above wavelength range, the entire absorption band including this wavelength may be within the above wavelength range, or it may extend beyond the above wavelength range. Furthermore, when there are multiple absorption maximums, it is sufficient that the absorption maximum wavelength exhibiting the greatest absorbance is within the above wavelength range. That is, absorption maximum wavelengths other than the absorption maximum wavelength exhibiting the greatest absorbance may be located either inside or outside the above wavelength range XX to YY nm. In the present invention, the main absorption wavelength band of the dye refers to the main absorption wavelength band of the dye measured in the state of a polarizing plate protective film. Specifically, in the Examples described below, this is measured in the state of a polarizing plate protective film in which a light-absorbing layer is laminated on a substrate under the conditions described in the section "Measurement of Transmittance and Calculation of Absorption Maximum." In the present invention, "(meth)acrylate" refers to either or both of acrylate and methacrylate, "(meth)acrylic acid" refers to either or both of acrylic acid and methacrylic acid, and "(meth)acryloyl" refers to either or both of acryloyl and methacryloyl.

[0009] The polarizing plate protective film of the present invention uses a dipyrromethene dye and exhibits excellent absorption tailing and light resistance. Also, the polarizing plate and liquid crystal display device of the present invention use a dipyrromethene dye in the polarizing plate protective film constituting them and exhibit excellent absorption tailing and light resistance.

[0010] FIG. 1 is a schematic diagram showing an outline of one embodiment of a liquid crystal display device equipped with a polarizing plate of the present invention.

[0011] [Polarizer Protective Film] The polarizer protective film of the present invention is a polarizer protective film containing a light-absorbing layer containing a resin and a dye containing a quencher-containing dipyrromethene dye (hereinafter simply referred to as "dye"). The polarizer protective film of the present invention, having the above-described structure, can exhibit excellent absorption tailing and lightfastness, even while using a dipyrromethene dye. While the reason for this is unclear, it is believed that the quencher-containing dipyrromethene dye contained in the light-absorbing layer can deactivate the excited state of the dipyrromethene dye excited by light irradiation to the ground state due to the quencher moiety contained in the quencher-containing dipyrromethene dye, thereby suppressing a decrease in absorbance. Furthermore, the polarizer of the present invention, which includes the polarizer protective film of the present invention and a polarizer, can exhibit superior lightfastness that exceeds that of the polarizer protective film of the present invention alone, as shown in the examples described below.

[0010] This is because the polarizer is configured to suppress the transmission of oxygen molecules, thereby preventing the quencher moiety contained in the quencher-containing dipyrromethene dye from being oxidized by oxygen and deteriorating, and is therefore thought to exhibit superior light resistance compared to the light resistance exhibited by the polarizer protective film alone. Furthermore, the polarizer protective film of the present invention can achieve excellent light resistance by using the quencher-containing dipyrromethene dye without using the catechol-coordinated dipyrromethene boron complex compound having a specific structure described in Patent Document 1 or the dipyrromethene cobalt complex having a specific structure in which two dipyrromethene ligands are coordinated described in Patent Document 2. As a result, the light resistance and the absorption tail of the dipyrromethene dye can be excellent.

[0012] The polarizing plate protective film of the present invention is a film provided directly on at least one surface of a polarizer or indirectly via another layer such as an adhesive layer, and serves to protect the polarizer by preventing the polarizer from being scratched or contaminated by foreign matter during the manufacturing process, transportation process, storage, etc. Note that the polarizing plate protective film of the present invention may be a polarizing plate protective film made of a light-absorbing layer, or may be a polarizing plate protective film in which the light-absorbing layer is provided on a substrate film described below, and may be a self-supporting film consisting of a single light-absorbing layer, or may not be a self-supporting film. Note that when the polarizing plate protective film of the present invention is incorporated into the polarizing plate of the present invention or when the polarizing plate of the present invention is incorporated into a liquid crystal display device, if a substrate film is laminated on the light-absorbing layer in the polarizing plate protective film of the present invention, the substrate film may be incorporated while still laminated on the light-absorbing layer, or the substrate film may be incorporated in a state where it is peeled off from the light-absorbing layer.

[0013] [Light-absorbing layer] <Dye> The light-absorbing layer contains a dye containing a quencher-containing dipyrromethene dye. In the polarizing plate protective film of the present invention, the dye containing a quencher-containing dipyrromethene dye is preferably dispersed (preferably dissolved) in the resin constituting the light-absorbing layer. This dispersion may be random, regular, or the like.

[0014] (Dipyrromethene Dyes with Built-in Quenchers) In the present invention, the term "dipyrromethene dyes with built-in quenchers" refers to dyes in which a quencher moiety is covalently linked to a dipyrromethene dye via a linking group. Examples of the dipyrromethene dyes with built-in quenchers include dipyrromethene dyes with built-in electron-donating quenchers, in which the quencher moiety is an electron-donating quencher moiety, and dipyrromethene dyes with built-in electron-accepting quenchers, in which the quencher moiety is an electron-accepting quencher moiety. The electron-donating quencher moiety refers to a structural moiety that donates an electron to the lower-energy-level SOMO (Singly Occupied Molecular Orbital) of two SOMOs (Singly Occupied Molecular Orbitals) of the dipyrromethene dye in an excited state, and then accepts an electron from the higher-energy-level SOMO of the dipyrromethene dye, thereby deactivating the excited dipyrromethene dye to the ground state. The electron-accepting quencher moiety refers to a structural moiety that accepts an electron from the SOMO with the higher energy level of the two SOMOs of the dipyrromethene dye in an excited state and then donates an electron to the SOMO with the lower energy level of the dipyrromethene dye, thereby deactivating the excited dipyrromethene dye to the ground state. As shown in the above mechanism, the quencher-containing dipyrromethene dye contained in the light-absorbing layer can effectively suppress the decrease in absorbance and the generation of fluorescence associated with light absorption by the dipyrromethene dye by the quencher moiety linked to the dipyrromethene dye. Therefore, the quencher moiety in the quencher-containing dipyrromethene dye is a quencher moiety that can quench the fluorescence of the dipyrromethene dye, and it is not important which part of the chemical structure of the quencher-containing dipyrromethene dye corresponds to the quencher moiety.

[0015] Examples of the electron-donating quencher moiety include a ferrocenyl group represented by the following general formula (2M), and the aryl groups described in paragraphs

[0199] to

[0212] and

[0234] to

[0287] of WO 2019 / 066043, Aurore Loudet and Kevin Burgess, Chemical Reviews, 2007, Vol. 107, No. 11, pp. 4896-4898 of pp. 4891-4932, and Hisato Sunahara et al., Journal of the American Chemical Society, 2007, Vol. 129, No. 17, Examples of the quencher moiety include the quencher moiety in the quencher compound described on pages 5597-5604, and are preferably a ferrocenyl group represented by the following general formula (2M): or at least one of an amino group, an alkoxy group, a hydroxy group, and a nitro group, or an aryl group having at least one of these as a substituent, and more preferably a ferrocenyl group represented by the following general formula (2M): Furthermore, examples of the electron-accepting quencher moiety include the quencher moiety in the quencher compound described in paragraphs

[0288] to

[0310] of WO 2019 / 066043.

[0016] A ferrocenyl group represented by general formula (2M)

[0017] In general formula (2M), L represents a single bond or a divalent linking group that is not conjugated with the dipyrromethene dye (hereinafter referred to as the "dipyrromethene dye portion") in the quencher-containing dipyrromethene dye. １ｍ ~R ９ｍ represents a hydrogen atom or a substituent. M is an atom that can constitute a metallocene compound, and represents Fe, Co, Ni, Ti, Cu, Zn, Zr, Cr, Mo, Os, Mn, Ru, Sn, Pd, Rh, V, or Pt. * represents a bonding site to the dipyrromethene dye moiety. In the present invention, when L in general formula (2M) is a single bond, the cyclopentadienyl ring (R in general formula (2M)) that is bonded to the dipyrromethene dye moiety is a cyclopentadienyl ring. １ｍ The ring having the formula (I) is not included in the conjugated structure that is conjugated with the dipyrromethene dye moiety.

[0018] The divalent linking group that can be taken as L is not particularly limited as long as it is a linking group that is not conjugated with the dipyrromethene dye moiety, and may contain the above-mentioned conjugated structure inside it or at the end of the cyclopentadiene ring in general formula (2M). Examples of the divalent linking group include an alkylene group having 1 to 20 carbon atoms, an arylene group having 6 to 20 carbon atoms, a divalent heterocyclic group obtained by removing two hydrogen atoms from a heterocycle, -CH=CH-, -CO-, -CS-, -NR- (wherein R represents a hydrogen atom or a monovalent substituent), -O-, -S-, and -SO ２ - or -N=CH-, or a divalent linking group formed by combining a plurality of these (preferably 2 to 6). Preferred are alkylene groups having 1 to 8 carbon atoms, arylene groups having 6 to 12 carbon atoms, -CH=CH-, -CO-, -NR- (wherein R is as defined above), -O-, -S-, and -SO ２ - and -N=CH- or a divalent linking group formed by combining two or more (preferably 2 to 6) groups selected from this group, and particularly preferred are alkylene groups having 1 to 4 carbon atoms, phenylene groups, -CO-, -NH-, -O- and -SO ２ - or a linking group formed by combining two or more (preferably 2 to 6) groups selected from this group. The combined divalent linking group is not particularly limited, but may be -CO-, -NH-, -O-, or -SO ２ A group containing - is preferred, and is -CO-, -NH-, -O- or -SO ２ A linking group formed by combining two or more types of -, or -CO-, -NH-, -O- and -SO ２ - is a linking group formed by combining at least one of - with an alkylene group or an arylene group. ２ Examples of the linking group formed by combining two or more types of - include -COO-, -OCO-, -CONH-, -NHCOO-, -NHCONH-, and -SO ２ -NH-, -CO-, -NH-, -O- and -SO ２Examples of the linking group formed by combining at least one of - with an alkylene group or an arylene group include groups formed by combining -CO-, -COO-, or -CONH- with an alkylene group or an arylene group. The substituent that can be taken as R is not particularly limited, and can be any of R in the general formula (P) described later. １ ~R ６ The substituents are the same as those that can be taken as the substituents.

[0019] L is a single bond, an alkylene group having 1 to 8 carbon atoms, an arylene group having 6 to 12 carbon atoms, —CH═CH—, —CO—, —NR— (wherein R is as defined above), —O—, —S—, or —SO ２ A group selected from the group consisting of - and -N=CH- or a group formed by combining two or more groups selected from this group is preferred.

[0020] L may have one or more substituents. The substituents that L may have are not particularly limited, and examples thereof include R １ ~R ６ When L has a plurality of substituents, the substituents bonded to adjacent atoms may be bonded to each other to form a ring structure.

[0021] The alkylene group that can be taken as L may be any of linear, branched, or cyclic, so long as it has 1 to 20 carbon atoms, and examples thereof include methylene, ethylene, propylene, methylethylene, methylmethylene, dimethylmethylene, 1,1-dimethylethylene, butylene, 1-methylpropylene, 2-methylpropylene, 1,2-dimethylpropylene, 1,3-dimethylpropylene, 1-methylbutylene, 2-methylbutylene, 3-methylbutylene, 4-methylbutylene, 2,4-dimethylbutylene, 1,3-dimethylbutylene, pentylene, Examples of L include hexylene, heptylene, octylene, ethane-1,1-diyl, propane-2,2-diyl, cyclopropane-1,1-diyl, cyclopropane-1,2-diyl, cyclobutane-1,1-diyl, cyclobutane-1,2-diyl, cyclopentane-1,1-diyl, cyclopentane-1,2-diyl, cyclopentane-1,3-diyl, cyclohexane-1,1-diyl, cyclohexane-1,2-diyl, cyclohexane-1,3-diyl, cyclohexane-1,4-diyl, methylcyclohexane-1,4-diyl, etc. In the alkylene group, L may contain -CO-, -CS-, -NR- (wherein R is as defined above), -O-, -S-, -SO ２ When a linking group containing at least one of - and -N=CH- is adopted, the group such as -CO- may be incorporated at any position in the alkylene group, and the number of groups incorporated is not particularly limited.

[0022] The arylene group that can be used as L is not particularly limited as long as it is a group having 6 to 20 carbon atoms, and examples thereof include R １ ~R ６ Among the aryl groups that can be taken as L, there can be mentioned groups in which one hydrogen atom has been further removed from each of the groups exemplified as the aryl group having 6 to 20 carbon atoms. The heterocyclic group that can be taken as L is not particularly limited, and examples thereof include R １ ~R ６ Examples of the heterocyclic group include groups in which one hydrogen atom has been further removed from each of the groups exemplified as the heterocyclic group that can be taken as the heterocyclic group.

[0023] In general formula (2M), the remaining partial structure excluding the linking group L corresponds to a structure (metallocene structural part) obtained by removing one hydrogen atom from a metallocene compound. In the present invention, the metallocene compound that serves as the metallocene structural part can be any known metallocene compound without any particular limitation, as long as it is a compound that conforms to the partial structure defined by general formula (2M) above (a compound in which a hydrogen atom is bonded in place of L). The metallocene structural part defined by general formula (2M) will be specifically described below.

[0024] In general formula (2M), R １ｍ ~R ９ｍ R each represents a hydrogen atom or a substituent. １ｍ ~R ９ｍ The substituents that can be used as the substituents are not particularly limited, but for example, R １ ~R ６ The substituents R can be selected from those which can be taken as R １ｍ ~R ９ｍ are each preferably a hydrogen atom, a halogen atom, an alkyl group, an acyl group, an alkoxy group, an amino group, or an amide group, more preferably a hydrogen atom, a halogen atom, an alkyl group, an acyl group, or an alkoxy group, still more preferably a hydrogen atom, a halogen atom, an alkyl group, or an acyl group, particularly preferably a hydrogen atom, a halogen atom, or an alkyl group, and most preferably a hydrogen atom.

[0025] R １ｍ ~R ９ｍ Examples of alkyl groups that can be used as R １Among the alkyl groups that can be taken as R, alkyl groups having 1 to 8 carbon atoms are preferred, and examples thereof include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, isobutyl, pentyl, tert-pentyl, hexyl, octyl, and 2-ethylhexyl. This alkyl group may have a halogen atom as a substituent. Examples of alkyl groups substituted with a halogen atom include chloromethyl, dichloromethyl, trichloromethyl, bromomethyl, dibromomethyl, tribromomethyl, fluoromethyl, difluoromethyl, trifluoromethyl, 2,2,2-trifluoroethyl, perfluoroethyl, perfluoropropyl, and perfluorobutyl. In addition, R １ｍ In the alkyl group which can be taken as the above, at least one methylene group forming the carbon chain may be substituted with -O- or -CO-. Examples of the alkyl group in which a methylene group is substituted with -O- include alkyl groups in which a terminal methylene group is substituted, such as methoxy, ethoxy, propoxy, isopropoxy, isobutoxy, sec-butoxy, tert-butoxy, 2-methoxyethoxy, chloromethyloxy, dichloromethyloxy, trichloromethyloxy, bromomethyloxy, dibromomethyloxy, tribromomethyloxy, fluoromethyloxy, difluoromethyloxy, trifluoromethyloxy, 2,2,2-trifluoroethyloxy, perfluoroethyloxy, perfluoropropyloxy, and perfluorobutyloxy, as well as alkyl groups in which an internal methylene group of the carbon chain, such as 2-methoxyethyl, is substituted. Examples of the alkyl group in which a methylene group is substituted with —CO— include acetyl, propionyl, monochloroacetyl, dichloroacetyl, trichloroacetyl, trifluoroacetyl, propan-2-one-1-yl, and butan-2-one-1-yl.

[0026] In general formula (2M), M is an atom that can constitute a metallocene compound and represents Fe, Co, Ni, Ti, Cu, Zn, Zr, Cr, Mo, Os, Mn, Ru, Sn, Pd, Rh, V, or Pt. Among these, M is preferably Fe, Ti, Co, Ni, Zr, Ru, or Os, more preferably Fe, Ti, Ni, Ru, or Os, still more preferably Fe or Ti, and most preferably Fe.

[0027] Further, a 2-hydroxy-5-methoxy-phenyl group, a 3,4,5-trimethoxyphenyl group, a 2,4,6-trimethoxyphenyl group, a 2,6-dimethoxyphenyl group, a 6-hydroxynaphthyl group, a 4-methoxynaphthyl group, a 2,4,6-trimethylphenyl group, and a 9-phenylanthracenyl group are also preferred examples of the electron-donating quencher moiety.

[0028] On the other hand, the electron-accepting quencher moiety is preferably a structure having an electron-withdrawing substituent such as a halogen atom or a nitro group, and preferred examples thereof include a 3-nitrophenyl group, a 3,5-dinitrophenyl group, a 2-methoxy-5-nitro-phenyl group, a nitro group, and an iodine atom.

[0029] The ferrocenyl group represented by the general formula (2M) includes L, R １ｍ ~R ９ｍ and a group formed by combining the preferred ones of M and M together are preferred, and for example, L is a single bond, an alkylene group having 2 to 8 carbon atoms, an arylene group having 6 to 12 carbon atoms, -CH=CH-, -CO-, -NR- (wherein R is as defined above), -O-, -S-, -SO ２ - and -N=CH- or a combination of two or more groups selected from this group, and R １ｍ ~R ９ｍ Examples of the groups include a group formed by combining a hydrogen atom, a halogen atom, an alkyl group, an acyl group, or an alkoxy group as L and Fe as M. Among these, groups formed by combining a single bond or an arylene group having 6 to 12 carbon atoms as L and Fe as R are particularly preferred. １ｍ ~R ９ｍ is preferably a group formed by combining a hydrogen atom, a halogen atom, an alkyl group, an acyl group, or an alkoxy group with Fe as M; L is preferably a single bond or an arylene group having 6 to 12 carbon atoms; and R１ｍ ~R ９ｍ A group formed by combining a hydrogen atom as the group and Fe as M is more preferred.

[0030] In the above-mentioned quencher-incorporating dipyrromethene dye, the dipyrromethene dye refers to a dye in which a dipyrromethene ligand, which is a monovalent bidentate ligand, forms a complex with a typical element or a transition element. The typical element or transition element to which the dipyrromethene ligand is coordinated is not particularly limited, and examples thereof include B, Zn, Mg, Si, Sn, Rh, Pt, Pd, Mo, Mn, Pb, Cu, Ni, Co, and Fe, with B being preferred, and B being more preferred. Furthermore, the typical element or transition element to which the dipyrromethene ligand is coordinated may have a ligand other than the dipyrromethene ligand, and may further include a fluorine atom, a fluorine atom, or a fluorine atom represented by the R ７ and R ８ The ligand is preferably a fluorine atom, or a ligand of a carboxylic acid, a ketone, a diketone or an acetoacetic ester, more preferably a fluorine atom.

[0031] The dipyrromethene dye containing a quencher is preferably a dipyrromethene dye containing an electron-donating quencher, and more preferably a dipyrromethene dye containing an electron-donating quencher represented by the following general formula (P).

[0032] Dipyrromethene dyes containing an electron-donating quencher represented by general formula (P)

[0033] In the above formula, R １ ~R ６ represents a hydrogen atom or a substituent. ７ and R ８ represents a fluorine atom or a ligand coordinated by an oxygen atom. ７ and R ８ is a ligand coordinated by an oxygen atom, R ７ and R ８ may be a bidentate ligand formed by linking R ９represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, or an electron-donating quencher moiety. １ ~R ９ At least one of the groups comprises an electron-donating quencher moiety.

[0034] (i) R １ ~R ６ R １ ~R ６ represents a hydrogen atom or a substituent. １ ~R ６Examples of the substituent that can be adopted as the alkyl group include a halogen atom (e.g., fluorine, chlorine, bromine), an alkyl group (preferably having 1 to 48 carbon atoms, more preferably having 1 to 24 carbon atoms, which is a linear, branched, or cyclic alkyl group, such as methyl, ethyl, propyl, isopropyl, butyl, t-butyl, pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, dodecyl, hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl, 1-norbornyl, and 1-adamantyl), an alkenyl group (preferably having 2 to 48 carbon atoms, more preferably having 1 to 24 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, t-butyl, pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, dodecyl, hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl, 1-norbornyl, and 1-adamantyl), and an alkenyl group (preferably having 2 to 48 carbon atoms, more preferably having 1 to 24 carbon atoms). alkenyl groups having 2 to 18 carbon atoms, for example, vinyl, allyl, 3-buten-1-yl), aryl groups (preferably aryl groups having 6 to 48 carbon atoms, more preferably 6 to 24 carbon atoms, for example, phenyl, naphthyl), heterocyclic groups (preferably heterocyclic groups having 1 to 32 carbon atoms, more preferably 1 to 18 carbon atoms, for example, 2-thienyl, 4-pyridyl, 2-furyl, 2-pyrimidinyl, 1-pyridyl, 2-benzothiazolyl, 1-imidazolyl, 1-pyrazolyl, benzotriazol-1-yl), silyl groups (preferably having 3 to 38 carbon atoms, more preferably 1 to 24 carbon atoms, for example, phenyl, naphthyl), silyl groups having 3 to 18 carbon atoms, for example, trimethylsilyl, triethylsilyl, tributylsilyl, t-butyldimethylsilyl, and t-hexyldimethylsilyl), hydroxyl groups, cyano groups, nitro groups, alkoxy groups (preferably alkoxy groups having 1 to 48 carbon atoms, more preferably 1 to 24 carbon atoms, for example, methoxy, ethoxy, 1-butoxy, 2-butoxy, isopropoxy, t-butoxy, dodecyloxy, cycloalkyloxy groups, for example, cyclopentyloxy and cyclohexyloxy), aryloxy groups (preferably 6 to 48 carbon atoms, More preferably, it is an aryloxy group having 6 to 24 carbon atoms, for example, phenoxy, 1-naphthoxy), a heterocyclic oxy group (preferably a heterocyclic oxy group having 1 to 32 carbon atoms, more preferably a heterocyclic oxy group having 1 to 18 carbon atoms, for example, 1-phenyltetrazole-5-oxy, 2-tetrahydropyranyloxy), a silyloxy group (preferably a silyloxy group having 1 to 32 carbon atoms, more preferably a silyloxy group having 1 to 18 carbon atoms, for example, trimethylsilyloxy, t-butyldimethylsilyloxy, diphenylmethylsilyloxy), an acyloxy group (preferably a group having 2 to 48 carbon atoms,more preferably an acyloxy group having 2 to 24 carbon atoms, for example, acetoxy, pivaloyloxy, benzoyloxy, dodecanoyloxy), an alkoxycarbonyloxy group (preferably an alkoxycarbonyloxy group having 2 to 48 carbon atoms, more preferably an alkoxycarbonyloxy group having 2 to 24 carbon atoms, for example, ethoxycarbonyloxy, t-butoxycarbonyloxy, a cycloalkyloxycarbonyloxy group, for example, cyclohexyloxycarbonyloxy), an aryloxycarbonyloxy group (preferably an aryloxycarbonyloxy group having 7 to 32 carbon atoms, more preferably an aryloxycarbonyloxy group having 7 to 24 carbon atoms, for example, phenoxycarbonyloxy),

[0035] carbamoyloxy groups (preferably carbamoyloxy groups having 1 to 48 carbon atoms, more preferably carbamoyloxy groups having 1 to 24 carbon atoms, for example, N,N-dimethylcarbamoyloxy, N-butylcarbamoyloxy, N-phenylcarbamoyloxy, N-ethyl-N-phenylcarbamoyloxy), sulfamoyloxy groups (preferably sulfamoyloxy groups having 1 to 32 carbon atoms, more preferably sulfamoyloxy groups having 1 to 24 carbon atoms, for example, N,N-diethylsulfamoyloxy, N-propylsulfamoyloxy), alkylsulfonyloxy groups (preferably alkylsulfonyloxy groups having 1 to 3 carbon atoms, for example, N,N-dimethylcarbamoyloxy, N-butylcarbamoyloxy, N-phenylcarbamoyloxy, N-ethyl-N-phenylcarbamoyloxy), alkylsulfonyloxy groups (preferably having 6 to 32 carbon atoms, more preferably having 6 to 24 carbon atoms, such as phenylsulfonyloxy), acyl groups (preferably having 1 to 48 carbon atoms, more preferably having 1 to 24 carbon atoms, such as formyl, acetyl, pivaloyl, benzoyl, tetradecanoyl, cyclohexanoyl), alkoxycarbonyl groups, an alkoxycarbonyl group (preferably an alkoxycarbonyl group having 2 to 48 carbon atoms, more preferably an alkoxycarbonyl group having 2 to 24 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, octadecyloxycarbonyl, cyclohexyloxycarbonyl, or 2,6-di-tert-butyl-4-methylcyclohexyloxycarbonyl); an aryloxycarbonyl group (preferably an aryloxycarbonyl group having 7 to 32 carbon atoms, more preferably an aryloxycarbonyl group having 7 to 24 carbon atoms, such as phenoxycarbonyl); a carbamoyl group (preferably a carbamoyl group having 1 to 48 carbon atoms, more preferably a carbamoyl group having 1 to 24 carbon atoms); yl groups, for example, carbamoyl, N,N-diethylcarbamoyl, N-ethyl-N-octylcarbamoyl, N,N-dibutylcarbamoyl, N-propylcarbamoyl, N-phenylcarbamoyl, N-methyl-N-phenylcarbamoyl, and N,N-dicyclohexylcarbamoyl; amino groups (preferably amino groups having 32 or less carbon atoms, more preferably amino groups having 24 or less carbon atoms, for example, amino, methylamino, N,N-dibutylamino, tetradecylamino, 2-ethylhexylamino, and cyclohexylamino); anilino groups (preferably having 6 to 32 carbon atoms,More preferably, it is an anilino group having 6 to 24 carbon atoms, for example, anilino, N-methylanilino), a heterocyclic amino group (preferably a heterocyclic amino group having 1 to 32 carbon atoms, more preferably 1 to 18 carbon atoms, for example, 4-pyridylamino), a carbonamido group (preferably a carbonamido group having 2 to 48 carbon atoms, more preferably 2 to 24 carbon atoms, for example, acetamido, benzamido, tetradecanamido, pivaloylamido, cyclohexanamido), a ureido group (preferably a ureido group having 1 to 32 carbon atoms, more preferably 1 to 24 carbon atoms, for example, ureido, N,N-diamino), methylureido, N-phenylureido), imido groups (preferably imido groups having 36 or less carbon atoms, more preferably 24 or less carbon atoms, for example, N-succinimido, N-phthalimido), alkoxycarbonylamino groups (preferably alkoxycarbonylamino groups having 2 to 48 carbon atoms, more preferably 2 to 24 carbon atoms, for example, methoxycarbonylamino, ethoxycarbonylamino, t-butoxycarbonylamino, octadecyloxycarbonylamino, cyclohexyloxycarbonylamino), aryloxycarbonylamino groups (preferably represents an aryloxycarbonylamino group having 7 to 32 carbon atoms, more preferably 7 to 24 carbon atoms, such as phenoxycarbonylamino), a sulfonamido group (preferably a sulfonamido group having 1 to 48 carbon atoms, more preferably 1 to 24 carbon atoms, such as methanesulfonamido, butanesulfonamido, benzenesulfonamido, hexadecanesulfonamido, and cyclohexanesulfonamido), a sulfamoylamino group (preferably a sulfamoylamino group having 1 to 48 carbon atoms, more preferably 1 to 24 carbon atoms, such as N,N-dipropylsulfa N-ethyl-N-dodecylsulfamoylamino), azo groups (preferably azo groups having 1 to 32 carbon atoms, more preferably an azo group having 1 to 24 carbon atoms, for example, phenylazo, 3-pyrazolylazo), alkylthio groups (preferably an alkylthio group having 1 to 48 carbon atoms, more preferably an alkylthio group having 1 to 24 carbon atoms, for example, methylthio, ethylthio, octylthio, cyclohexylthio), arylthio groups (preferably an arylthio group having 6 to 48 carbon atoms, more preferably an arylthio group having 6 to 24 carbon atoms, for example, phenylthio), heterocyclic thio groups (preferably having 1 to 32 carbon atoms,More preferably, it is a heterocyclic thio group having 1 to 18 carbon atoms, for example, 2-benzothiazolylthio, 2-pyridylthio, 1-phenyltetrazolylthio), an alkylsulfinyl group (preferably an alkylsulfinyl group having 1 to 32 carbon atoms, more preferably an alkylsulfinyl group having 1 to 24 carbon atoms, for example, dodecanesulfinyl), an arylsulfinyl group (preferably an arylsulfinyl group having 6 to 32 carbon atoms, more preferably an arylsulfinyl group having 6 to 24 carbon atoms, for example, phenylsulfinyl), an alkylsulfonyl group (preferably an alkylsulfonyl group having 1 to 48 carbon atoms, more preferably an alkylsulfonyl group having 1 to 24 carbon atoms, for example, methylsulfonyl, ethylsulfonyl, propylsulfonyl, butylsulfonyl, isopropylsulfonyl, 2-ethylhexylsulfonyl, hexadecylsulfonyl, octylsulfonyl, cyclohexylsulfonyl), an arylsulfonyl group (preferably an alkylsulfonyl group having 6 carbon atoms, arylsulfonyl groups having from 1 to 48 carbon atoms, more preferably from 6 to 24 carbon atoms, such as phenylsulfonyl and 1-naphthylsulfonyl), sulfamoyl groups (preferably sulfamoyl groups having 32 or less carbon atoms, more preferably 24 or less carbon atoms, such as sulfamoyl, N,N-dipropylsulfamoyl, N-ethyl-N-dodecylsulfamoyl, N-ethyl-N-phenylsulfamoyl and N-cyclohexylsulfamoyl), sulfo groups, phosphonyl groups (preferably phosphonyl groups having 1 to 32 carbon atoms, more preferably 1 to 24 carbon atoms, such as phenoxyphosphonyl, octyloxyphosphonyl and phenylphosphonyl), and phosphinoylamino groups (preferably phosphinoylamino groups having 1 to 32 carbon atoms, more preferably 1 to 24 carbon atoms, such as diethoxyphosphinoylamino and dioctyloxyphosphinoylamino). １ ~R ６ Examples of the substituent that can be adopted include the electron-donating quencher moiety in the above-mentioned quencher-containing dipyrromethene dye.

[0036] R １ ~R ６ The substituents that can be taken as R may be further substituted with a substituent. In this case, R １ ~R ６ The substituents that may be further substituted by the substituents that can be taken as R１ ~R ６ Examples of substituents that can be taken as R １ ~R ６ When the substituent that can be taken as R is substituted with two or more substituents, these two or more substituents may be the same or different. １ ~R ６ Preferred examples of the group include a hydrogen atom, a halogen atom, an alkyl group, an acyl group, an alkoxycarbonyl group, an acyloxy group, an amido group, a carbamoyl group, an aryl group, a heterocyclic group, and a nitro group.

[0037] R １ and R ２ , R ２ and R ３ , R ４ and R ５ , R ５ and R ６ may each independently bond to each other to form a 5-, 6-, or 7-membered saturated or unsaturated ring. The 5-, 6-, or 7-membered saturated or unsaturated ring formed may be further substituted with a substituent. In this case, the substituent that the 5-, 6-, or 7-membered saturated or unsaturated ring formed may further have includes the above-mentioned R １ ~R ６ When the 5-, 6-, or 7-membered saturated or unsaturated ring formed is substituted with two or more substituents, these two or more substituents may be the same or different.

[0038] (ii) R ７ and R ８ R ７ and R ８ represents a fluorine atom or a ligand coordinated by an oxygen atom. ７ and R ８ is a ligand coordinated by an oxygen atom, R ７ and R ８ may be a bidentate ligand formed by linking R ７ and R ８ As the ligand coordinated by the oxygen atom, which can be taken as R ７and R ８ In addition to bidentate ligands formed by linking R, examples of the ligand include carboxylate ion ligands such as acetato, ketone or diketone ligands such as acetonato or acetylacetonato, acetoacetic ester ligands, and catechol ligands, and the carboxylate ion ligands, ketone or diketone ligands, and acetoacetic ester ligands are preferred. The benzene ring in the catechol ligand may have a substituent, and examples of the substituents that may be included include the above-mentioned R １ ~R ６ The description of the substituents that can be taken as R ７ and R ８ are preferably all fluorine atoms.

[0039] (iii) R ９ R ９ represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, or an electron-donating quencher moiety. ９ Examples of the halogen atom, alkyl group, aryl group and heterocyclic group that can be taken as R ９ The halogen atom, alkyl group, aryl group and heterocyclic group that can be taken as R １ ~R ６ The descriptions of the halogen atom, alkyl group, aryl group, and heterocyclic group that can be taken as R can be applied to each of them. ９ Examples of the electron-donating quencher moiety that can be used as R include the electron-donating quencher moiety in the above-mentioned quencher-containing dipyrromethene dye. ９ is preferably a hydrogen atom, an alkyl group, an aryl group, or a heterocyclic group.

[0040] However, R １ ~R ９ At least one of "R" contains an electron-donating quencher moiety. １ ~R ９ "at least one of R contains an electron-donating quencher moiety" means that R １ ~R ９ At least one of R is an electron-donating quencher moiety, or R １ ~R ９is a substituent substituted with an electron-donating quencher moiety. The substitution position containing the electron-donating quencher moiety is R １ ~R ９ Any of the above is acceptable, １ ~R ６ and R ９ and R ２ , R ５ and R ９ More preferably, R ９ It is more preferable that R ７ and R ８ is a fluorine atom, the substitution position containing the electron-donating quencher moiety is １ ~R ６ and R ９ and R ２ , R ５ and R ９ More preferably, R ９ The electron-donating quencher moiety can be the same as that described for the electron-donating quencher moiety in the above-mentioned quencher-incorporating dipyrromethene dye, and is preferably a ferrocenyl group represented by the above-mentioned general formula (2M), or at least one of an amino group, an alkoxy group, a hydroxy group, and a nitro group, or an aryl group having at least one of these as a substituent, and more preferably a ferrocenyl group represented by the above-mentioned general formula (2M).

[0041] Examples of the above-mentioned quencher-containing dipyrromethene dye include the following exemplary compounds. In the following, Me represents a methyl group, and Et represents an ethyl group. However, the above-mentioned quencher-containing dipyrromethene dye is not limited to these.

[0042]

[0043]

[0044] The quencher-containing dipyrromethene dye can be synthesized by a conventional method, for example, by referring to the description in Dalton Trans., 2010, Vol. 39, pp. 9929-9935 and JP-A No. 2023-051753. The quencher-containing dipyrromethene dye has a good absorption tail, and therefore, in the polarizing plate protective film of the present invention, the 10% absorption width of the quencher-containing dipyrromethene dye can be, for example, less than 66%, preferably 65% ​​or less, more preferably 64% or less, and even more preferably 63% or less.

[0045] It is also preferable that the light-absorbing layer contains two or more dyes with different main absorption wavelength bands, i.e., two or more dyes with different main absorption wavelength bands, including at least one of the quencher-containing dipyrromethene dyes. It is known that the use of a combination of two or more dyes with different main absorption wavelength bands can result in reduced lightfastness compared to the use of a single dye alone. However, even when the quencher-containing dipyrromethene dye is used in combination with two or more dyes with different main absorption wavelength bands, it can exhibit lightfastness comparable to that of a single quencher-containing dipyrromethene dye, thereby suppressing the deterioration in lightfastness that can occur when two or more dyes with different main absorption wavelength bands are combined. For example, when the light-absorbing layer contains at least two of the following dyes A to D, at least one of which is the quencher-containing dipyrromethene dye, it can exhibit lightfastness comparable to that of a single quencher-containing dipyrromethene dye. Although the present invention is not limited thereto, a preferred embodiment is one in which the light-absorbing layer contains the quencher-containing dipyrromethene dye as the dye B described below, and further contains at least one of the dyes A, C, and D described below (preferably the dye A described below).

[0046] The dye preferably includes at least one of the following dyes A to D. Dye A: A dye having a main absorption wavelength band in the wavelength range of 390 to 435 nm Dye B: A dye having a main absorption wavelength band in the wavelength range of 480 to 520 nm Dye C: A dye having a main absorption wavelength band in the wavelength range of 580 to 620 nm Dye D: A dye having a main absorption wavelength band in the wavelength range of 640 to 780 nm Dye A is not particularly limited, and various dyes can be used, as long as it has a main absorption wavelength band in the wavelength range of 390 to 435 nm in the polarizing plate protective film of the present invention. Dye B is not particularly limited, and various dyes can be used, as long as it has a main absorption wavelength band in the wavelength range of 480 to 520 nm in the polarizing plate protective film of the present invention. Dye C is not particularly limited, and various dyes can be used, as long as it has a main absorption wavelength band in the wavelength range of 580 to 620 nm in the polarizing plate protective film of the present invention. Dye D is not particularly limited, and various dyes can be used, as long as it has a main absorption wavelength band in the wavelength range of 640 to 780 nm in the polarizing plate protective film of the present invention. The wavelength range in which dye A has its main absorption wavelength band is preferably 400 to 435 nm, more preferably 405 to 435 nm. The wavelength range in which dye B has its main absorption wavelength band is preferably 490 to 520 nm, more preferably 490 to 515 nm. The wavelength range in which dye C has its main absorption wavelength band is preferably 580 to 615 nm, more preferably 585 to 610 nm. The wavelength range in which dye D has its main absorption wavelength band is preferably 640 to 750 nm, more preferably 650 to 700 nm. However, at least one of dyes A to D contains the above-mentioned quencher-containing dipyrromethene dye, and it is particularly preferred that the dye contains a quencher-containing dipyrromethene dye corresponding to dye B.

[0047] Specific examples of dye A include porphyrin-based, squaraine-based, cyanine (CY)-based, pyrrole methine-based, and indoaniline-based dyes. Preferred examples of the pyrrole methine dye include the pyrrole methine dyes represented by formula (A1) or (A2) described in paragraphs

[0022] to

[0066] of WO 2022 / 138925 and the following compound (E-42).

[0048]

[0049] Preferred examples of the porphyrin dye include porphyrin dyes represented by the following general formula (7), which contain copper, magnesium, zinc, cobalt, titanium, iron, vanadium, or vanadium oxide as a central metal.

[0050]

[0051] In the above formula, X １ ~X ８ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a substituted or unsubstituted ethenyl group, a substituted or unsubstituted ethynyl group, an aryl group, an aryloxy group, an aryloxycarbonyl group, an alkylthio group, an arylthio group, or an acyl group. １ ~X ８ Adjacent groups among R may be bonded to each other to form an aromatic ring together with the carbon atoms that they substitute. １８ ~R ２１ represents an aryl group. M represents copper, magnesium, zinc, cobalt, titanium, iron, vanadium, or vanadium oxide. In the above formula, the nitrogen atoms located above and below M on the paper indicate that they are coordinated to M by an unshared electron pair.

[0052] X １ ~X ８ The halogen atom, alkyl group, alkoxy group, aryl group, aryloxy group, aryloxycarbonyl group, alkylthio group, arylthio group and acyl group that can be taken as R １ ~R ６ The descriptions of the halogen atom, alkyl group, alkoxy group, aryl group, aryloxy group, aryloxycarbonyl group, alkylthio group, arylthio group and acyl group in the substituents that can be taken as X can be applied. １ ~X ８The alkyl group that can be taken as the substituent may have a substituent, and examples of the alkyl group substituted with a substituent include an aralkyl group, a halogenoalkyl group, an alkoxyalkyl group, an aryloxyalkyl group, an aralkyloxyalkyl group, and a halogenoalkoxyalkyl group. The substituent in the alkyl group substituted with these substituents also applies to the R １ ~R ６ or the corresponding substituent in the substituent that can be taken as R in the above general formula (P). １ ~R ６ The description of the substituents that are a combination of multiple corresponding substituents in the substituents that can be taken as X can also be applied. １ ~X ８ The alkoxy group which can be taken as R in the general formula (P) may have a substituent, and examples of the alkoxy group substituted with a substituent include an aralkyloxy group and a halogenoalkoxy group. The substituent in the alkoxy group substituted with these substituents is also the same as that in R in the general formula (P) above. １ ~R ６ The description of the corresponding substituents in the substituents that can be taken as X can be applied. １ ~X ８ The substituted ethenyl group and the substituent that the substituted ethynyl group may have include R １ ~R ６ The substituents in the substituents that can be taken as R can be applied. １８ ~R ２１ The aryl group that can be taken as R in the above general formula (P) is １ ~R ６ The description of the aryl group in the substituents that can be taken as the aryl group can be applied.

[0053] Among them, X １ ~X ８ is preferably a hydrogen atom, a halogen atom, a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms.

[0054] Furthermore, as the porphyrin dye represented by general formula (7), commercially available products can be used without any restrictions, and for example, porphyrin compounds that satisfy the main absorption wavelength band of dye A, which are sold by Tokyo Chemical Industry Co., Ltd., Yamada Chemical Co., Ltd., etc., can be used. For example, FDB-002 (trade name, manufactured by Yamada Chemical Co., Ltd.) used in the examples described below corresponds to the porphyrin dye represented by general formula (7).

[0055] The dye A preferably contains a pyrrole methine dye represented by general formula (A1) of WO 2022 / 138925, since the absorption waveform in the main absorption wavelength band is sharp.

[0056] Specific examples of dye B include pyrrole methine (PM), rhodamine (RH), boron dipyrromethene (BODIPY), and squaraine (SQ) dyes. The above-mentioned quencher-containing dipyrromethene dyes are also preferred as dye B. Specific examples of dye C include tetraaza porphyrin (TAP), squaraine, and cyanine (CY) dyes. Preferred examples thereof include squaraine dyes and quencher-containing dyes represented by any one of general formulas (1) to (9) described in paragraphs

[0072] to

[0169] of WO 2021 / 221122, as well as the following compounds (C-121) and (C-122).

[0057]

[0058] Among these, the above-mentioned dyes B and C preferably contain squaraine dyes, and more preferably contain squaraine dyes represented by general formula (1) described in WO 2021 / 221122, because they have sharp absorption waveforms in the main absorption wavelength band. By using dyes B and C with sharp absorption waveforms as described above, the original color of the image of the OLED display device can be maintained at an excellent level.

[0059] Specific examples of dye D include porphyrin-based, squaraine-based, cyanine (CY)-based, and indoaniline-based dyes. Preferred examples of squaraine-based dyes include squaraine-based dyes represented by general formula (14) described in paragraphs

[0089] to

[0099] of WO 2023 / 228799. Preferred examples of indoaniline-based dyes include indoaniline-based dyes represented by general formula (v) or (va-a) described in paragraphs

[0064] to

[0072] of WO 2023 / 234353.

[0060] The total content of the dyes in the light-absorbing layer is preferably 0.1 to 50% by mass, more preferably 0.3 to 40% by mass, even more preferably 0.5 to 30% by mass, particularly preferably 0.7 to 20% by mass, and especially preferably 1.0 to 15% by mass. The total content of the quencher-containing dipyrromethene dyes in the light-absorbing layer is preferably 0.1 to 30% by mass, more preferably 0.3 to 20% by mass, even more preferably 0.5 to 15% by mass, particularly preferably 0.7 to 10% by mass, and especially preferably 1.0 to 10% by mass.

[0061] When the light-absorbing layer contains the dyes A to D, the total content of the dyes A to D in the light-absorbing layer is preferably 0.01 to 45% by mass, more preferably 0.1 to 30% by mass, and even more preferably 0.1 to 10% by mass. When the light-absorbing layer contains the dyes A to D, the content of each of the dyes A to D in the light-absorbing layer is preferably 0.01 to 45% by mass, more preferably 0.1 to 30% by mass, and even more preferably 0.1 to 10% by mass.

[0062] <Resin> The resin contained in the light-absorbing layer (hereinafter also referred to as "matrix resin") is not particularly limited as long as it can disperse (preferably dissolve) the dye and has the desired light transmittance (preferably a light transmittance of 80% or more in the visible wavelength range of 400 to 800 nm). The matrix resin preferably contains a low-polarity matrix resin that enables the quencher-containing dipyrromethene dye to exhibit sharper absorption. Here, low polarity preferably means that the fd value defined by the following relational formula I is 0.45 or greater. Relational formula I: fd = δd / (δd + δp + δh) In relational formula I, δd, δp, and δh respectively represent the terms corresponding to the London dispersion force, the dipole-dipole force, and the hydrogen bonding force relative to the solubility parameter δt calculated by the Hoy method. Specific calculation methods are described in paragraphs

[0131] to

[0133] of WO 2022 / 138925. That is, fd indicates the ratio of δd to the sum of δd, δp, and δh. By setting the fd value to 0.45 or more, it becomes easier to obtain a sharper absorption waveform. Furthermore, when the light absorbing layer contains two or more types of matrix resins, the fd value is calculated as follows: fd=Σ(w ｉ ・fd ｉ ) where w ｉ is the mass fraction of the i-th matrix resin, fd ｉ indicates the fd value of the i-th matrix resin.

[0063] Furthermore, if the matrix resin exhibits a certain degree of hydrophobicity, the moisture content of the light-absorbing layer can be reduced to, for example, 0.5% or less, which is preferable from the viewpoint of improving the light resistance of the polarizing plate protective film of the present invention including the light-absorbing layer. The resin may contain any conventional component in addition to the polymer. However, the fd of the matrix resin is a calculated value for the polymer constituting the matrix resin.

[0064] Preferred examples of the matrix resin include polystyrene resin and cyclic polyolefin resin. Typically, the fd value of polystyrene resin is 0.45 to 0.60, and the fd value of cyclic polyolefin resin is 0.45 to 0.70. In addition to these preferred resins, it is also preferable to use resin components that impart functionality to the light-absorbing layer, such as resins containing polymers having an aromatic ring or alicyclic structure in the side chain, as described below, and resin components that impart functionality to the light-absorbing layer, such as extensible resin components, release property-controlling resin components, and adhesion-improving resin components, as described below. In other words, in the present invention, the term "matrix resin" is used to include not only the resins described above and those described below, but also extensible resin components, release property-controlling resin components, and adhesion-improving resin components. It is preferable for the matrix resin to contain polystyrene resin in order to sharpen the absorption waveform of the dye.

[0065] (Polystyrene Resin) The polystyrene contained in the polystyrene resin refers to a polymer containing a styrene component. The polystyrene preferably contains 50% by mass or more of the styrene component. The light-absorbing layer may contain one type of polystyrene or two or more types of polystyrene. Here, the styrene component is a structural unit derived from a monomer having a styrene skeleton in its structure. In order to control the photoelastic coefficient and hygroscopicity to values ​​within a preferred range for the light-absorbing layer constituting the polarizing plate protective film, the polystyrene more preferably contains 70% by mass or more of the styrene component, and even more preferably contains 85% by mass or more. It is also preferable that the polystyrene is composed only of the styrene component.

[0066] Among polystyrenes, polystyrenes composed solely of a styrene component include homopolymers of styrene compounds and copolymers of two or more styrene compounds. Here, the term "styrene compound" refers to a compound having a styrene skeleton in its structure, and includes not only styrene but also compounds into which a substituent has been introduced to the extent that the ethylenically unsaturated bond of styrene can function as a reactive (polymerizable) group. Specific styrene compounds include, for example, styrene; alkylstyrenes such as α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 3,5-dimethylstyrene, 2,4-dimethylstyrene, o-ethylstyrene, p-ethylstyrene, and tert-butylstyrene; and substituted styrenes in which a hydroxyl group, an alkoxy group, a carboxyl group, a halogen atom, or the like has been introduced into the benzene nucleus of styrene, such as hydroxystyrene, tert-butoxystyrene, vinylbenzoic acid, o-chlorostyrene, and p-chlorostyrene. Among these, from the standpoints of availability and material cost, the polystyrene used in the present invention is preferably a homopolymer of styrene (i.e., polystyrene).

[0067] Furthermore, the constituent components other than the styrene component that may be contained in the polystyrene are not particularly limited. That is, the polystyrene may be a styrene-diene copolymer, a styrene-polymerizable unsaturated carboxylic acid ester copolymer, or the like. A mixture of polystyrene and synthetic rubber (e.g., polybutadiene and polyisoprene) can also be used. High-impact polystyrene (HIPS) obtained by graft-polymerizing styrene onto synthetic rubber is also preferred. Also preferred is polystyrene obtained by dispersing a rubber-like elastomer in a continuous phase of a polymer containing a styrene component (e.g., a copolymer of a styrene component and a (meth)acrylic acid ester component) and graft-polymerizing the copolymer onto the rubber-like elastomer (graft-type high-impact polystyrene, referred to as "graft HIPS"). Furthermore, so-called styrene-based elastomers can also be suitably used. The polystyrene may also be hydrogenated (hydrogenated polystyrene). The hydrogenated polystyrene is not particularly limited, but hydrogenated styrene-diene copolymers such as hydrogenated styrene-butadiene-styrene block copolymer (SEBS) obtained by hydrogenating SBS (styrene-butadiene-styrene block copolymer) and hydrogenated styrene-isoprene-styrene block copolymer (SEPS) obtained by hydrogenating SIS (styrene-isoprene-styrene block copolymer) are preferred. Only one type of hydrogenated polystyrene may be used, or two or more types may be used. Furthermore, the polystyrene may be modified polystyrene. The modified polystyrene is not particularly limited, but examples thereof include polystyrene into which a reactive group such as a polar group has been introduced. Specific examples thereof include acid-modified polystyrene such as maleic acid-modified polystyrene and epoxy-modified polystyrene.

[0068] As the polystyrene, multiple types of polystyrenes with different compositions, molecular weights, etc. can be used in combination. Polystyrene-based resins can be obtained by conventional methods such as anionic, bulk, suspension, emulsion, or solution polymerization. In addition, in polystyrene, at least a portion of the unsaturated double bonds in the benzene rings of the conjugated diene and styrene monomer may be hydrogenated. The hydrogenation rate can be measured by nuclear magnetic resonance (NMR) spectroscopy.

[0069] As the polystyrene resin, commercially available products may be used, for example, "CLEAREN 530L" and "CLEAREN 730L" manufactured by Denki Kagaku Kogyo Co., Ltd., "TUFPREN 126S" and "ASAPRENE T411" manufactured by Asahi Kasei Corporation, "KRATON D1102A" and "KRATON D1116A" manufactured by Kraton Polymers Japan, "STYROLUX S" and "STYROLUX T" manufactured by Styrolusion, "Asaflex 840" and "Asaflex 860" manufactured by Asahi Kasei Chemicals Corporation (SBS), "679", "HF77", and "SGP-10" manufactured by PS Japan, "DIC STYRENE XC-515" and "DIC STYRENE XC-535" manufactured by DIC Corporation (GPPS), "475D", "H0103", and "HT478" manufactured by PS Japan, and "DIC STYRENE" manufactured by DIC. GH-8300-5 (both collectively referred to as HIPS). Examples of hydrogenated polystyrene resins include the "Tuftec H Series" manufactured by Asahi Kasei Chemicals Corporation, the "Kraton G Series" manufactured by Shell Japan (both collectively referred to as SEBS), the "Dynaron" (hydrogenated styrene-butadiene random copolymer) manufactured by JSR Corporation, and the "Septon" (SEPS) manufactured by Kuraray Co., Ltd. Examples of modified polystyrene resins include the "Tuftec M Series" manufactured by Asahi Kasei Chemicals Corporation, the "Epofriend" manufactured by Daicel Corporation, the "Polar Group Modified Dynaron" manufactured by JSR Corporation, and the "Reseda" manufactured by Toagosei Co., Ltd.

[0070] It is also preferable that the polystyrene resin contains a polystyrene resin (also referred to as an adhesion improving resin) that exhibits adhesion improving properties. The adhesion improving resin is more preferably the above-mentioned polystyrene resin to which a functional group and / or a thermally crosslinkable group that imparts adhesiveness has been added. Examples of functional groups that impart adhesiveness include groups that form hydrogen bonds with polyvinyl alcohol, such as oxazolyl groups (sometimes referred to as oxazolin groups), carbonamide groups, sulfonamide groups, and hydroxy groups. It is also preferable that the adhesion improving resin has a thermally crosslinkable group. The thermally crosslinkable group is a group that undergoes a crosslinking reaction upon heating, and specific examples thereof include a carboxyl group, oxazolyl group, hydroxyl group, isocyanato group, maleimide group, acetoacetoxy group, epoxy group, amino group, furyl group, and acid anhydride group. When both the adhesion improving resin and the copolymer (a) described below have a thermally crosslinkable group, the copolymer (a) can be fixed to the surface of the polarizing plate protective film by reacting these thermally crosslinkable groups, thereby enabling the development of higher adhesiveness. The reaction between the thermally crosslinkable groups can be carried out by heating. In this case, the copolymer (a) can be fixed to the surface of the polarizing plate protective film functional film by reacting the thermally crosslinkable groups by heating, which is preferable because it does not require a process of incorporating a compound (monomer) having a reactive group in the molecule and curing this monomer by irradiation with ionizing radiation such as ultraviolet light to fix the copolymer (a) to the surface of the functional film.

[0071] Specific examples of the adhesion improving resin include the styrene-based resins having thermal crosslinkable groups described in paragraphs

[0090] and

[0091] of International Publication No. 2019 / 066043. However, the adhesion improving resin is not limited to these.

[0072] The above-mentioned hydrogenated polystyrene resins and those to which functional groups and / or thermally crosslinkable groups that impart adhesiveness are added can also be preferably used as adhesion-improving resins. Specific examples include the "Tuftec H Series" manufactured by Asahi Kasei Chemicals Corporation, the "Kraton G Series" manufactured by Shell Japan (both SEBS), the "Dynaron" (hydrogenated styrene-butadiene random copolymer) manufactured by JSR Corporation, the "Septon" (SEPS) manufactured by Kuraray Co., Ltd., the "Tuftec M Series" manufactured by Asahi Kasei Chemicals Corporation, the "Epofriend" manufactured by Daicel Corporation, the "Polar Group-Modified Dynaron" manufactured by JSR Corporation, and the "Reseda" manufactured by Toagosei Co., Ltd.

[0073] The adhesion improving resin may be used alone, or multiple types of adhesion improving resins with different repeating unit compositions, molecular weights, etc. may be used in combination. The adhesion improving resin can be obtained by known anionic, bulk, suspension, emulsion, or solution polymerization methods. In the adhesion improving resin, the unsaturated double bonds of the benzene rings of the conjugated diene and / or styrene monomer may be hydrogenated. The hydrogenation rate can be measured by nuclear magnetic resonance (NMR) spectroscopy. The content of the adhesion improving resin may be within the range of the content of the matrix resin.

[0074] The light-absorbing layer preferably contains a polyphenylene ether resin in addition to the polystyrene resin. By incorporating both polystyrene resin and polyphenylene ether resin, the toughness of the light-absorbing layer can be improved, and defects such as cracks can be suppressed even in harsh environments such as high temperatures and high humidity. Examples of the polyphenylene ether resin include Zylon S201A, S202A, and S203A (all trade names) manufactured by Asahi Kasei Corporation. Alternatively, a resin prepared by pre-mixing polystyrene resin and polyphenylene ether resin may be used. Examples of mixed resins of polystyrene resin and polyphenylene ether resin include Zylon 1002H, Zylon 1000H, Zylon 600H, Zylon 500H, Zylon 400H, Zylon 300H, and Zylon 200H (all trade names) manufactured by Asahi Kasei Corporation. When the light-absorbing layer contains a polystyrene resin and a polyphenylene ether resin, the mass ratio of the two, polystyrene resin / polyphenylene ether resin, is preferably 99 / 1 to 50 / 50, more preferably 98 / 2 to 60 / 40, and even more preferably 95 / 5 to 70 / 30. By setting the blending ratio of the polyphenylene ether resin within the above preferred range, the light-absorbing layer has sufficient toughness, and when solution-formed, the solvent can be appropriately evaporated.

[0075] (Cyclic Polyolefin Resin) The cyclic olefin compound forming the cyclic polyolefin contained in the cyclic polyolefin resin (also referred to as polycycloolefin resin) is not particularly limited as long as it has a ring structure containing a carbon-carbon double bond, and examples thereof include norbornene compounds, monocyclic olefin compounds other than norbornene compounds, cyclic conjugated diene compounds, and vinyl alicyclic hydrocarbon compounds. Examples of cyclic polyolefins include (1) polymers containing structural units derived from norbornene compounds, (2) polymers containing structural units derived from monocyclic olefin compounds other than norbornene compounds, (3) polymers containing structural units derived from cyclic conjugated diene compounds, (4) polymers containing structural units derived from vinyl alicyclic hydrocarbon compounds, and hydrogenated polymers containing structural units derived from each of the compounds (1) to (4). In the present invention, polymers containing structural units derived from norbornene compounds and polymers containing structural units derived from monocyclic olefin compounds include ring-opened polymers of each compound. As the cyclic polyolefin resin, the description of the cyclic polyolefin resin described in paragraphs

[0112] to

[0125] of WO 2023 / 228799 can be applied as is.

[0076] (Polymer having an aromatic ring or alicyclic structure in the side chain) As the polymer constituting the above resin, a polymer having an aromatic ring or alicyclic structure in the side chain (hereinafter also referred to as polymer P) is also preferred from the viewpoint that the molecular weight of the resin is less likely to decrease due to ultraviolet irradiation, and a (meth)acrylic polymer containing a structural unit having an aromatic ring or alicyclic structure is more preferred. Here, the (meth)acrylic polymer refers to a polymer containing at least one structural unit derived from (meth)acrylic acid and a structural unit derived from a (meth)acrylic acid ester. In addition, in the present invention, the "main chain" refers to the relatively longest bond chain in the molecule of the polymer compound, and the "side chain" refers to an atomic group branched from the main chain.

[0077] Examples of monomers that lead to structural units having an aromatic ring include benzyl acrylate, benzyl methacrylate, naphthyl acrylate, naphthyl methacrylate, naphthyl methyl acrylate, and naphthyl methyl methacrylate. When the polymer P does not contain a structural unit having a carboxy group, the content of the structural unit having an aromatic ring is preferably 5 to 100 mol%, more preferably 10 to 100 mol%, and even more preferably 20 to 100 mol%, when the total of all structural units of the polymer P is taken as 100 mol%. When the polymer P contains a structural unit having a carboxy group, the content of the structural unit having an aromatic ring is preferably 0 to 97 mol%, more preferably 0 to 95 mol%, even more preferably 0 to 90 mol%, and particularly preferably 0 to 80 mol%, when the total of all structural units of the polymer P is taken as 100 mol%.

[0078] Examples of monomers that derive structural units having an alicyclic structure include dicyclopentanyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, and adamantyl (meth)acrylate. When the polymer P contains structural units having an alicyclic structure, the content of the structural units having an alicyclic structure is preferably 1 to 90 mol%, more preferably 5 to 90 mol%, and even more preferably 5 to 80 mol%, when the total of all structural units of the polymer P is taken as 100 mol%.

[0079] It is also preferable that the polymer P contains a structural unit having a carboxy group. Examples of monomers that derive a structural unit having a carboxy group include (meth)acrylic acid, crotonic acid, itaconic acid, maleic acid, and fumaric acid, with (meth)acrylic acid being preferred. When the polymer P contains a structural unit having a carboxy group, the content of the structural unit having a carboxy group is preferably 1 to 70 mol%, more preferably 1 to 60 mol%, even more preferably 5 to 60 mol%, particularly preferably 10 to 60 mol%, and especially preferably 20 to 55 mol%, when the total of all structural units of the polymer P is taken as 100 mol%.

[0080] From the viewpoint of adjusting the glass transition temperature, the polymer P may contain a structural unit having an alkyl group having 1 to 14 carbon atoms. Examples of structural units having an alkyl group having 1 to 14 carbon atoms include structural units derived from alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, sec-butyl (meth)acrylate, pentyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-ethylbutyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, lauryl (meth)acrylate, and tetradecyl (meth)acrylate. In the present invention, structural units having an alkyl group having 1 to 14 carbon atoms may be used alone, or two or more types may be used in combination. The content of structural units having an alkyl group having 1 to 14 carbon atoms in the polymer P is preferably 0 to 95 mol %.

[0081] The polymer constituting the resin preferably contains the above-mentioned polystyrene resin and the above-mentioned polymer P. In this case, the above-mentioned polystyrene resin preferably contains a polystyrene resin that exhibits the above-mentioned adhesion improving effect. The content ratio of the above-mentioned polystyrene resin to the above-mentioned polymer P in the polymer constituting the resin is, for example, preferably 30 to 95:5 to 70, more preferably 40 to 95:5 to 60, and even more preferably 50 to 95:5 to 50.

[0082] The mass average molecular weight (Mw) of the polymer constituting the resin is preferably 5,000 to 500,000, more preferably 10,000 to 200,000, and even more preferably 15,000 to 200,000. In the present invention, the mass average molecular weight of the polymer can be measured as a polystyrene-equivalent molecular weight by gel permeation chromatography (GPC). Specifically, a GPC apparatus HLC-8220 (trade name, manufactured by Tosoh Corporation) is used, tetrahydrofuran is used as the eluent, and G3000HXL + G2000HXL columns (both trade names, manufactured by Tosoh Corporation) are used, and the measurement can be performed at 23°C with a flow rate of 1 mL / min by RI (differential refractive index). When two or more polymers are contained, it is preferable that the mass average molecular weight of each polymer falls within the above-mentioned preferred range.

[0083] The content of the matrix resin in the light-absorbing layer is preferably 50% by mass or more but less than 100% by mass, more preferably 60% by mass or more but less than 100% by mass, and even more preferably 65% ​​by mass or more but less than 100% by mass. The upper limit is also preferably 99% by mass or less, more preferably 97% by mass or less. The matrix resin may be used alone or in combination of two or more types.

[0084] (Extensible Resin Component) The light-absorbing layer can contain an appropriately selected resin component that exhibits extensibility (also referred to as an extensible resin component). Specific examples include acrylonitrile-butadiene-styrene resin (ABS resin), styrene-butadiene resin (SB resin), isoprene resin, butadiene resin, polyether-urethane resin, and silicone resin. These resins may also be hydrogenated as appropriate. As the extensible resin component, it is preferable to use an ABS resin or an SB resin, and it is more preferable to use an SB resin.

[0085] The SB resin may be, for example, a commercially available product, such as TR2000, TR2003, TR2250 (all trade names, manufactured by JSR Corporation), Clearene 210M, 220M, 730V (all trade names, manufactured by Denka Company Limited), Asaflex 800S, 805, 810, 825, 830, 840 (all trade names, manufactured by Asahi Kasei Corporation), and Eporex SB2400, SB2610, SB2710 (all trade names, manufactured by Sumitomo Chemical Co., Ltd.).

[0086] When the light absorbing layer contains an extensible resin component, the matrix resin preferably contains the extensible resin component in an amount of 15 to 95% by mass, more preferably 20 to 50% by mass, and even more preferably 25 to 45% by mass.

[0087] As the extensible resin component, when a sample having a thickness of 30 μm and a width of 10 mm is prepared using the extensible resin component alone and the breaking elongation at 25° C. is measured in accordance with JIS 7127, the extensible resin component preferably exhibits a breaking elongation of 10% or more, more preferably 20% or more.

[0088] (Adhesion-improving resin component) It is also preferable to incorporate a component (adhesion-improving resin component) into the matrix resin that improves the adhesion between the light-absorbing layer in the polarizing plate protective film and a layer that is in contact with the light-absorbing layer, etc., thereby achieving higher adhesion between the light-absorbing layer in the polarizing plate protective film and other layers, films, films, or other articles. In particular, it is preferable to incorporate a component that improves the adhesion between the polarizing plate protective film and a polarizer. In the following description, a case will be described in which the object to which the light-absorbing layer in the polarizing plate protective film is adhered (adhesion object) is an adhesive layer or a polarizer, but the adhesion object is not limited to these.

[0089] -Boronic Acid Group- or Boronic Acid Ester Group-Containing Copolymer-The light-absorbing layer may contain, as a component that enhances adhesion to other layers, a boronic acid group- or boronic acid ester group-containing copolymer, for example, a copolymer containing a repeating unit represented by the following general formula (ID) and a repeating unit represented by the following general formula (IID) (hereinafter also referred to as "copolymer (a)"), and / or a crosslinking reaction product derived from copolymer (a). The light-absorbing layer preferably contains at least one of copolymer (a) and a crosslinking reaction product derived from copolymer (a), and may contain only one of them or both.

[0090]

[0091] In general formula (ID), R １ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. ２ represents an alkyl group having 1 to 20 carbon atoms and having at least one fluorine atom as a substituent, or —Si(R ａ３ ) (R ａ４ ) represents a group containing O—. ａ３ and R ａ４ each independently represents an alkyl group having 1 to 12 carbon atoms or an aryl group which may have a substituent. L represents a divalent linking group composed of at least one of -O-, -(C=O)O-, -O(C=O)-, a divalent aliphatic chain group, and a divalent aliphatic cyclic group.

[0092]

[0093] In general formula (IID), R １０ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. １１ and R １２ each independently represents a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group; R １１ and R １２ may be linked to X. １ represents a divalent linking group.

[0094] --Copolymer (a) or a crosslinking reaction product derived from copolymer (a)-- The copolymer (a) or a crosslinking reaction product derived from copolymer (a) that can be contained in the light-absorbing layer will be described below.

[0095] R in general formula (ID) １ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and still more preferably a hydrogen atom or a methyl group.

[0096] R in general formula (ID) ２ is preferably an alkyl group having 1 to 20 carbon atoms and having at least one fluorine atom as a substituent (fluoroalkyl group), more preferably a fluoroalkyl group having 1 to 18 carbon atoms, and even more preferably a fluoroalkyl group having 2 to 15 carbon atoms. The number of fluorine atoms in the fluoroalkyl group is preferably 1 to 25, more preferably 3 to 21, and most preferably 5 to 21.

[0097] In general formula (ID), L represents a divalent linking group consisting of at least one selected from the group consisting of -O-, -(C=O)O-, -O(C=O)-, a divalent aliphatic chain group, and a divalent aliphatic cyclic group. １ The carbon atom on the side is bonded to C=O, and R ２ represents a bond between R and O, and -O(C=O)- represents a bond between R １ The carbon atom on the side is bonded to O, and R ２ represents a bond between C═O and C═O. As the divalent aliphatic chain group which can be taken by L, an alkylene group having 1 to 20 carbon atoms is preferred, and an alkylene group having 1 to 10 carbon atoms is more preferred. As the divalent aliphatic cyclic group which can be taken by L, a cycloalkylene group having 3 to 20 carbon atoms is preferred, and a cycloalkylene group having 3 to 15 carbon atoms is more preferred. As L, -(C═O)O- or -O(C═O)- is preferred, and -(C═O)O- is more preferred.

[0098] From the viewpoint of surface uneven distribution (the function of unevenly distributing the copolymer (a) on the surface of the light-absorbing layer), which is advantageous for adhesion, and from the viewpoint of radical polymerizability, it is particularly preferable that the repeating unit represented by general formula (ID) is a repeating unit represented by the following general formula (IIID):

[0099]

[0100] In general formula (IIID), R １ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. ma and na each independently represent an integer of 1 to 18, and satisfy the condition ma+na≦19. X represents a hydrogen atom or a fluorine atom.

[0101] R in general formula (IIID) １ is R in general formula (ID). １ The same applies to the preferred range.

[0102] In general formula (IIID), ma and na each independently represent an integer of 1 to 18. From the viewpoint of surface uneven distribution, which is advantageous for adhesion, and from the viewpoint of availability of raw materials and ease of production, ma in general formula (IIID) is preferably an integer of 1 to 8, and more preferably an integer of 1 to 5. Furthermore, na is preferably an integer of 1 to 15, more preferably an integer of 1 to 12, even more preferably an integer of 2 to 10, and most preferably an integer of 5 to 7.

[0103] X in general formula (IIID) represents a hydrogen atom or a fluorine atom, and is preferably a fluorine atom. The repeating unit represented by general formula (ID) or general formula (IIID) may further have a substituent, if substitutable. As the substituent, those selected from the substituent group Y described in paragraphs

[0154] to

[0168] of International Publication No. 2019 / 066043 are preferred, and a hydroxy group is more preferred.

[0104] The repeating unit represented by formula (ID) or (IIID) can be introduced by polymerization of a monomer. Preferred examples of the monomer include 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3,3-pentafluoropropyl (meth)acrylate, 2-(perfluorobutyl)ethyl (meth)acrylate, 2-(perfluorohexyl)ethyl (meth)acrylate, 2-(perfluorooctyl)ethyl (meth)acrylate, 2-(perfluorodecyl)ethyl (meth)acrylate, 2-(perfluoro-3-methylbutyl)ethyl (meth)acrylate, 2-(perfluoro-5-methylhexyl)ethyl (meth)acrylate, 2-(perfluoro-7-methyloctyl)ethyl (meth)acrylate, 1H,1H,3H-tetrafluoropropyl (meth)acrylate, 1H,1H,5H-octafluoropentyl (meth)acrylate, and 1H,1H,7H-decyl (meth)acrylate. Examples of such hydroxypropyl acrylates include decafluoroheptyl (meth)acrylate, 1H,1H,9H-hexadecafluorononyl (meth)acrylate, 1H-1-(trifluoromethyl)trifluoroethyl (meth)acrylate, 1H,1H,3H-hexafluorobutyl (meth)acrylate, 3-perfluorobutyl-2-hydroxypropyl (meth)acrylate, 3-perfluorohexyl-2-hydroxypropyl (meth)acrylate, 3-perfluorooctyl-2-hydroxypropyl (meth)acrylate, 3-(perfluoro-3-methylbutyl)-2-hydroxypropyl (meth)acrylate, 3-(perfluoro-5-methylhexyl)-2-hydroxypropyl (meth)acrylate, and 3-(perfluoro-7-methyloctyl)-2-hydroxypropyl (meth)acrylate.

[0105] R in general formula (ID) ２ is -Si(R ａ３ ) (R ａ４ )O—(siloxane bond), and —Si(R ａ３ ) (R ａ４Another preferred embodiment is a polysiloxane structure containing a siloxane bond represented by the formula (IVD) O- as a repeating unit. In this case, the copolymer (a) is preferably a graft copolymer having a polysiloxane structure introduced into a side chain. The compound having a siloxane bond for obtaining this graft copolymer is more preferably a compound represented by the following general formula (IVD):

[0106]

[0107] R ａ３ and R ａ４ each independently represents an alkyl group (including a haloalkyl group) having 1 to 12 carbon atoms, or an aryl group. The alkyl group is preferably an alkyl group having 1 to 10 carbon atoms. Examples include a methyl group, an ethyl group, and a hexyl group. The alkyl group may be a haloalkyl group substituted with a halogen atom, and the haloalkyl group is preferably a fluorinated alkyl group having 1 to 10 carbon atoms. Examples include a trifluoromethyl group and a pentafluoroethyl group. The aryl group is preferably an aryl group having 6 to 20 carbon atoms. Examples include a phenyl group and a naphthyl group. Among these, R ａ３ and R ａ４ is preferably a methyl group, a trifluoromethyl group, or a phenyl group, and particularly preferably a methyl group. ａ１ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. ａ５ represents an alkyl group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms. nn is preferably an integer of 10 to 1000, more preferably an integer of 20 to 500, and even more preferably an integer of 30 to 200. ａ３ may be the same or different, and nn R ａ４ may be the same or different.

[0108] Examples of compounds having a siloxane bond for graft copolymerization include polysiloxane macromers containing a (meth)acryloyl group at one end (e.g., Silaplane 0721, Silaplane 0725 (all trade names, manufactured by JNC Corporation), AK-5, AK-30, AK-32 (all trade names, manufactured by Toagosei Co., Ltd.), KF-100T, X-22-169AS, KF-102, X-22-3701IE, X-22-164B, X-22-164C, X-22-5002, X-22-173B, X-22-174D, X-22-167B, and X-22-161AS (all trade names, manufactured by Shin-Etsu Chemical Co., Ltd.)).

[0109] Next, the following general formula (IID) will be described. Copolymer (a) contains a repeating unit represented by general formula (IID) in addition to the repeating unit represented by general formula (ID). In copolymer (a), the repeating unit represented by general formula (IID) has a strong interaction with hydroxyl groups. That is, when a coating solution of a composition for forming a light-absorbing layer is applied to a substrate and an adhesive layer having hydroxyl groups is then formed on the surface of the coating solution, some or all of the repeating units represented by general formula (IID) interact with the hydroxyl groups, causing copolymer (a) to diffuse and be adsorbed at the interface of the adhesive layer having hydroxyl groups and inside the adhesive layer. Therefore, after the light-absorbing layer and the adhesive layer are brought into contact with each other, copolymer (a) having a repeating unit represented by general formula (IID) added to the coating solution exists in the light-absorbing layer, the adhesive layer, and the interface between them as a copolymer having the same chemical structure as general formula (IID), or as a derivative (crosslinked product) having a structure in which the repeating unit represented by general formula (IID) has reacted with the hydroxyl groups of the adhesive layer. In this way, because the copolymer (a) having a repeating unit represented by general formula (IID) interacts with the adhesive layer, the adhesion between the adhesive layer and the light-absorbing layer containing the copolymer (a) can be increased regardless of the ratio of the copolymer (a) present in the adhesive layer and / or the light-absorbing layer, and as a result, the adhesion to the polarizer via the adhesive layer can be increased. The adhesion between the polarizer containing polyvinyl alcohol and the light-absorbing layer can also be increased in a similar manner. Even when the light-absorbing layer is attached to something other than the adhesive layer, if the object has hydroxyl groups on its surface, the adhesion can be increased in the same way as in the case of the adhesive layer.

[0110]

[0111] In general formula (IID), R １０ is preferably a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and most preferably a hydrogen atom or a methyl group.

[0112] In general formula (IID), R １１ and R １２Examples of the substituted or unsubstituted aliphatic hydrocarbon group that can be used as the alkyl group include substituted or unsubstituted alkyl groups, alkenyl groups, and alkynyl groups. Specific examples of the alkyl group include linear, branched, or cyclic alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, hexadecyl, octadecyl, eicosyl, isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl, neopentyl, 1-methylbutyl, isohexyl, 2-methylhexyl, cyclopentyl, cyclohexyl, 1-adamantyl, and 2-norbornyl. Specific examples of the alkenyl group include linear, branched, or cyclic alkenyl groups such as vinyl, 1-propenyl, 1-butenyl, 1-methyl-1-propenyl, 1-cyclopentenyl, and 1-cyclohexenyl groups. Specific examples of the alkynyl group include ethynyl, 1-propynyl, 1-butynyl, and 1-octynyl groups.

[0113] R １１ and R １２ Specific examples of the substituted or unsubstituted aryl group that R may take include a phenyl group. Further examples include a group obtained by removing one hydrogen atom from a condensed ring formed by two to four benzene rings, and a group obtained by removing one hydrogen atom from a condensed ring formed by a benzene ring and an unsaturated five-membered ring, and specific examples include a naphthyl group, an anthryl group, a phenanthryl group, an indenyl group, an acenaphthenyl group, a fluorenyl group, and a pyrenyl group. １１ and R １２Examples of the substituted or unsubstituted heteroaryl groups that each of the above may take include heteroaryl groups obtained by removing one hydrogen atom from a heteroaromatic ring containing one or more heteroatoms selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom. Specific examples of heteroaromatic rings containing one or more heteroatoms selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom include pyrrole, furan, thiophene, pyrazole, imidazole, triazole, oxazole, isoxazole, oxadiazole, thiazole, thiadiazole, indole, carbazole, benzofuran, dibenzofuran, thianaphthene, dibenzothiophene, indazole, benzimidazole, anthranil, benzisoxazole, benzoxazole, benzothiazole, purine, pyridine, pyridazine, pyrimidine, pyrazine, triazine, quinoline, acridine, isoquinoline, phthalazine, quinazoline, quinoxaline, naphthyridine, phenanthroline, and pteridine.

[0114] R １１ and R １２ may be linked to each other, in which case R １１ and R １２ are each independently an alkyl group or an aryl group, and are preferably linked to each other; R １１ and R １２ It is more preferable that are alkyl groups and are linked to each other.

[0115] In general formula (IID), X １ Examples of the divalent linking group represented by the formula include -(C=O)O-, -O(C=O)-, -(C=O)NH-, -O-, -CO-, -NH-, -O(C=O)-NH-, -O(C=O)-O-, and -CH ２ - and having 7 or more carbon atoms. １ It is also preferable that the divalent linking group represented by the following formula (I) is an arylene group.

[0116] In general formula (IID), R １１ , R １２ and X １may be substituted with one or more substituents, if possible. Examples of the substituent include a monovalent non-metallic atomic group excluding a hydrogen atom, and are selected from, for example, the substituent group Y described in paragraphs

[0154] to

[0168] of WO 2019 / 066043. Furthermore, the substituents in the substituent group Y described in paragraphs

[0154] to

[0168] of WO 2019 / 066043 may, if possible, be bonded to each other or to the hydrocarbon group that substitutes them to form a ring.

[0117] R in general formula (IID) １１ and R １２ are each independently a hydrogen atom or an alkyl group, or are both alkyl groups which are bonded to each other to form a ring; R １１ and R １２ and are more preferably both hydrogen atoms or both alkyl groups and bonded to each other to form a ring.

[0118] From the viewpoint of adhesiveness, the repeating unit represented by general formula (IID) is preferably a repeating unit represented by the following general formula (VD): The improvement in adhesiveness due to the repeating unit represented by general formula (VD) is presumed to be due to the effect of bringing the polarity closer to that of the adhesive layer having a hydroxyl group.

[0119]

[0120] In general formula (VD), R １０ , R １１ and R １２ are R in general formula (IID), １０ , R １１ and R １２ It is synonymous with X. １１ -(C=O)O-, -O(C=O)-, -(C=O)NH-, -O-, -CO-, -CH ２ represents a divalent linking group selected from the group consisting of -. １２ -(C=O)O-, -O(C=O)-, -(C=O)NH-, -O-, -CO-, -NH-, -O(C=O)-NH-, -O(C=O)-O-, -CH ２- represents a divalent linking group containing at least one bond selected from the group consisting of - and at least one substituted or unsubstituted aromatic ring. １１ and the above X １２ The total number of carbon atoms is 7 or more.

[0121] X in general formula (VD) １１ As X, —(C═O)O—, —O(C═O)—, and —(C═O)NH— are preferred, and —(C═O)O— is most preferred. １２ X preferably contains 1 to 5 aromatic rings, more preferably 2 to 4 aromatic rings, and even more preferably 2 to 3 aromatic rings. １２ Examples of the aromatic ring contained in R in general formula (VD) include a benzene ring and a naphthalene ring. １０ , R １１ and R １２ The preferred ranges of R in general formula (IID) are １０ , R １１ and R １２ is the same as:

[0122] The repeating unit represented by formula (IID) or (VD) is more preferably a repeating unit represented by formula (VID) below.

[0123]

[0124] In the general formula (VID), X ２１ represents —(C═O)O— or —(C═O)NH—. X ２２ -(C=O)O-, -O(C=O)-, -(C=O)NH-, -O-, -CO-, -NH-, -O(C=O)-NH-, -O(C=O)-O-, -CH ２ - is a divalent linking group containing at least one bond selected from ２２ may contain a substituted or unsubstituted aromatic ring.

[0125] R in general formula (VID) １０ , R １１ and R １２ The preferred ranges of R in general formula (IID) are １０ , R １１ and R １２ It is the same as: X２２ The aromatic ring of １２ The aromatic ring is the same as that of

[0126] The repeating unit represented by general formula (IID), (VD), or (VID) can be obtained by polymerization of a monomer. Specific examples of preferred monomers that provide the repeating unit represented by general formula (IID), (VD), or (VID) include the monomers described in paragraphs

[0165] to

[0168] of International Publication No. 2019 / 066043. However, the present invention is not limited thereto.

[0127] Furthermore, the copolymer (a) in the present invention may have a repeating unit (other repeating unit) other than the repeating unit represented by general formula (ID) and the repeating unit represented by general formula (IID), if necessary.

[0128] Other types of monomers that provide other repeating units can be those described in Polymer Handbook 2nd ed., J. Brandrup, Wiley Interscience (1975), Chapter 2, pages 1 to 483. Examples include compounds having one addition-polymerizable unsaturated bond selected from acrylic acid, methacrylic acid, acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, dialkyl itaconates, and dialkyl or monoalkyl esters of fumaric acid.

[0129] Specific examples of monomers that provide other repeating units include the monomers described in paragraphs

[0171] to

[0175] of International Publication No. 2019 / 066043.

[0130] Furthermore, it is also possible to convert the structure of the polymer after polymerization by a polymer reaction, and introduce a structure other than the repeating unit represented by general formula (ID) or general formula (IID).

[0131] Furthermore, the copolymer (a) preferably has a thermally crosslinkable group. The thermally crosslinkable group of the copolymer (a) can be the same as that described for the polystyrene resin. The copolymer (a) preferably contains a repeating unit having a thermally crosslinkable group. Examples of a monomer that provides a repeating unit having a thermally crosslinkable group include a monomer that provides the above-mentioned other repeating unit and has a thermally crosslinkable group, or a monomer that provides the other repeating unit substituted with a thermally crosslinkable group.

[0132] It is particularly preferred that the copolymer (a) be thermally crosslinked with other compounds contained in the light-absorbing layer. By thermally crosslinking, the copolymer (a) can be fixed to the surface of the light-absorbing layer, and higher adhesion can be achieved between the light-absorbing layer and other layers, membranes, films, or other articles. In particular, it is preferred that the copolymer (a) and the styrene-based resin described below each have a thermally crosslinkable group that is reactive with each other.

[0133] The content of the repeating unit represented by general formula (ID) in the copolymer (a) is preferably 5 to 95 mass%, more preferably 8 to 90 mass%, and even more preferably 10 to 85 mass%, based on the total mass of the copolymer (a).

[0134] The content of the repeating unit represented by general formula (IID) in the copolymer (a) is preferably from 0.5 to 80 mass%, more preferably from 1 to 70 mass%, and even more preferably from 2 to 60 mass%, based on the total mass of the copolymer (a).

[0135] The content of the repeating unit having a thermal crosslinkable group in the copolymer (a) is preferably 0.5 to 90 mass %, more preferably 1 to 85 mass %, and even more preferably 2 to 80 mass %, based on the total mass of the copolymer (a).

[0136] The mass average molecular weight (Mw) of the copolymer (a) is preferably 1,000 to 200,000, more preferably 1,800 to 150,000, even more preferably 2,000 to 150,000, particularly preferably 2,500 to 140,000, and extremely preferably 20,000 to 120,000. The number average molecular weight (Mn) of the copolymer (a) is preferably 500 to 160,000, more preferably 600 to 120,000, even more preferably 600 to 100,000, particularly preferably 1,000 to 80,000, and extremely preferably 2,000 to 60,000. The dispersity (Mw / Mn) of the copolymer (a) is preferably 1.00 to 18.00, more preferably 1.00 to 16.00, even more preferably 1.00 to 14.00, particularly preferably 1.00 to 12.00, and extremely preferably 1.00 to 10.00. The mass average molecular weight and number average molecular weight are values ​​measured by gel permeation chromatography (GPC) under the following conditions. [Eluent] N-methyl-2-pyrrolidone (NMP) [Apparatus] EcoSEC HLC-8320GPC (manufactured by Tosoh Corporation) [Column] TSKgel SuperAWM-H (manufactured by Tosoh Corporation) [Column temperature] 40°C [Flow rate] 0.50 ml / min

[0137] The copolymer (a) can be synthesized by a known method.

[0138] Specific examples of the copolymer (a) include the copolymers described in paragraphs

[0185] to

[0188] of International Publication No. 2019 / 066043. However, the present invention is not limited thereto.

[0139] The content of copolymer (a) may be within the range of the content of the matrix resin. From the viewpoint of strengthening adhesion to the object to be adhered without impairing the function of the light-absorbing layer, the content of copolymer (a) is preferably 0.0001 to 40 mass%, more preferably 0.001 to 20 mass%, and even more preferably 0.005 to 10 mass%, when the total solid content (all components excluding the solvent) of the light-absorbing layer is taken as 100 mass%.

[0140] The matrix resin may contain, in addition to the adhesion-improving resin, a resin having the above-mentioned functional group imparting adhesiveness and / or a thermally crosslinkable group.

[0141] <Other Components> The light absorbing layer may contain a leveling agent (surfactant), an anti-fading agent described in paragraphs

[0245] to

[0261] of WO 2021 / 014973, a matting agent described in paragraphs

[0262] to

[0264] of WO 2021 / 014973, etc. Furthermore, when the light absorbing layer uses the matrix resin described in

[0145] to

[0189] of WO 2021 / 132674 as a resin, it may contain the following association inhibitor.

[0142] (Aggregation inhibitor) The light-absorbing layer preferably contains an aggregation inhibitor to inhibit or prevent the association of dye molecules in the light-absorbing layer by interacting with the dye. The aggregation inhibitor is preferably contained as a compound that sharpens the absorption waveform of the dye contained in the light-absorbing layer and exhibits the function of improving light fastness. The aggregation inhibitor used in the present invention may be any of the aggregation inhibitors described in paragraphs

[0177] to

[0228] of WO 2022 / 138925.

[0143] When the light-absorbing layer contains an association inhibitor, the content of the association inhibitor in the light-absorbing layer is preferably 0.1 to 30% by mass, more preferably 1 to 20% by mass, and even more preferably 2 to 15% by mass. The content of the association inhibitor in the light-absorbing layer is preferably 10 to 1,000 parts by mass, more preferably 20 to 700 parts by mass, and even more preferably 30 to 500 parts by mass, relative to 100 parts by mass of the total content of the dyes.

[0144] (Leveling Agent) A leveling agent (surfactant) can be appropriately mixed into the light-absorbing layer. Commonly used compounds can be used as the leveling agent, with fluorine-containing surfactants being particularly preferred. Specific examples include the compounds described in paragraphs

[0028] to

[0056] of JP-A No. 2001-330725. Preferred examples include copolymers comprising a structural unit having a fluorine-substituted alkyl group and a structural unit derived from an alkyl (meth)acrylate ester in a copolymer represented by formula (IV) described in paragraph

[0054] of JP-A No. 2001-330725. Furthermore, commercially available products such as the Megafac F (trade name) series manufactured by DIC Corporation can also be used. The content of the leveling agent in the light-absorbing layer can be adjusted appropriately depending on the purpose.

[0145] The light absorbing layer may contain, in addition to the above components, a low-molecular-weight plasticizer, an oligomer-based plasticizer, a retardation adjuster, an ultraviolet absorber, a deterioration inhibitor, a peeling promoter, an infrared absorber, an antioxidant, a filler, a compatibilizer, and the like.

[0146] <Method for producing light-absorbing layer> The light-absorbing layer can be produced by a conventional method, such as a solution film-forming method, a melt extrusion method, or a method (coating method) of forming a coating layer on a substrate film (release film) by any method, and stretching can also be combined as appropriate. The light-absorbing layer is preferably produced by a coating method. As the solution film-forming method and melt extrusion method, the descriptions of the solution film-forming method and melt extrusion method in

[0268] to

[0274] of WO 2021 / 014973 can be applied as is.

[0147] (Coating Method) In the coating method, a solution of the material for the light absorbing layer is applied to a substrate film to form a coating layer. A release agent or the like may be applied in advance to the surface of the substrate film as needed to control adhesion to the coating layer. The coating layer can be incorporated into a polarizing plate or a liquid crystal display device with the substrate film laminated thereon, or can be laminated to other components via an adhesive layer in a subsequent process, and then the substrate film can be peeled off and used. Any adhesive can be used as the adhesive constituting the adhesive layer. The substrate film can be stretched as needed with the solution of the material for the light absorbing layer applied to the substrate film or with the coating layer laminated thereon.

[0148] The solvent used in the solution of the material for the light-absorbing layer can be appropriately selected from the viewpoints of being able to dissolve or disperse the material for the light-absorbing layer, being able to easily form a uniform surface in the coating and drying steps, being able to ensure liquid preservation, having an appropriate saturated vapor pressure, etc.

[0149] -Addition of Dye (Pigment)- The timing of adding the dye to the material for the light absorbing layer is not particularly limited as long as it is added at the time of film formation. For example, the dye may be added at the time of synthesis of the polymer that constitutes the matrix resin, or may be mixed with the material for the light absorbing layer when preparing a coating liquid for the material for the light absorbing layer.

[0150] -Base film- The base film used to form the light absorbing layer by a coating method or the like preferably has a film thickness of 5 to 100 μm, more preferably 10 to 75 μm, and even more preferably 15 to 55 μm. When the film thickness is equal to or greater than the above-mentioned preferable lower limit, sufficient mechanical strength is easily ensured, and defects such as curling, wrinkling, and buckling are less likely to occur. Furthermore, when the film thickness is equal to or less than the above-mentioned preferable upper limit, when a multilayer film of the light absorbing layer and the base film is stored, for example, in the form of a long roll, the surface pressure applied to the multilayer film is easily adjusted to an appropriate range, and adhesion defects are less likely to occur.

[0151] The surface energy of the substrate film is not particularly limited, but the adhesive strength between the light-absorbing layer and the substrate film can be adjusted by adjusting the relationship between the surface energies of the material of the light-absorbing layer and the coating solution and the surface energy of the surface of the substrate film on which the light-absorbing layer is formed. If the difference in surface energy is reduced, the adhesive strength tends to increase, and if the difference in surface energy is increased, the adhesive strength tends to decrease, and the surface energy difference can be set appropriately.

[0152] The surface energy of the substrate film can be calculated using the Owens method from the contact angle values ​​of water and methylene iodide. A contact angle meter, DM901 (manufactured by Kyowa Interface Science Co., Ltd.), can be used to measure the contact angle. The surface energy of the substrate film on the side where the light-absorbing layer is formed is preferably 41.0 to 48.0 mN / m, and more preferably 42.0 to 48.0 mN / m. When the surface energy is equal to or greater than the preferred lower limit, the uniformity of the thickness of the light-absorbing layer can be improved, and when the surface energy is equal to or less than the preferred upper limit, the peel strength between the light-absorbing layer and the substrate film can be easily controlled within an appropriate range.

[0153] Furthermore, the surface unevenness of the substrate film is not particularly limited, but can be adjusted, for example, for the purpose of preventing adhesion failure when a multilayer film of the light absorbing layer and the substrate film is stored in a long roll form, depending on the relationship between the surface energy, hardness, and surface unevenness of the surface of the light absorbing layer and the surface energy and hardness of the surface of the substrate film opposite to the side on which the light absorbing layer is formed. Increasing the surface unevenness tends to suppress adhesion failure, while decreasing the surface unevenness tends to reduce the surface unevenness of the light absorbing layer and the haze of the polarizing plate protective film, and can be set appropriately.

[0154] Any material or film can be used as the substrate film. Specific examples of the material include polyester polymers (including polyethylene terephthalate), olefin polymers, cycloolefin polymers, (meth)acrylic polymers, cellulose polymers, and polyamide polymers. Furthermore, the substrate film can be subjected to a surface treatment to adjust its surface properties. For example, corona treatment, room temperature plasma treatment, saponification treatment, etc. can be performed to reduce the surface energy, and silicone treatment, fluorine treatment, olefin treatment, etc. can be performed to increase the surface energy.

[0155] -Peel Force Between Light-Absorbing Layer and Base Film- When the light-absorbing layer is formed by a coating method, the peel force between the light-absorbing layer and the base film can be controlled by adjusting the material of the light-absorbing layer, the material of the base film, the internal strain of the light-absorbing layer, etc. This peel force can be measured, for example, by a test in which the base film is peeled off in a 90° direction, and the peel force measured at a rate of 300 mm / min is preferably 0.001 to 5 N / 25 mm, more preferably 0.01 to 3 N / 25 mm, and even more preferably 0.05 to 1 N / 25 mm. If the peel force is equal to or greater than the preferred lower limit, peeling can be prevented except in the step of peeling the base film, and if the peel force is equal to or less than the preferred upper limit, peeling defects (e.g., zipping and cracking of the light-absorbing layer) can be prevented in the peeling step.

[0156] <Film Thickness of Light-Absorbing Layer> The film thickness of the light-absorbing layer is not particularly limited, but is preferably 1 to 18 μm, more preferably 1 to 12 μm, and even more preferably 1 to 8 μm. When the film thickness is equal to or less than the above-mentioned preferred upper limit, the addition of a high concentration of dye to a thin film can suppress a decrease in polarization degree due to fluorescence emitted by the dye (pigment). Furthermore, when a quencher and an anti-fading agent are contained, their effects are easily manifested. On the other hand, when the film thickness is equal to or greater than the above-mentioned preferred lower limit, uniformity of in-plane absorbance is easily maintained. Furthermore, by keeping the film thickness within the above-mentioned preferred range, when incorporated into a liquid crystal display device, display unevenness after aging at high temperature and high humidity is unlikely to occur, and stable transport during the manufacture of the light-absorbing layer and the polarizing plate can be achieved. In the present invention, a film thickness of 1 to 18 μm means that the thickness of the light-absorbing layer is within the range of 1 to 18 μm regardless of the location measured. This also applies to film thicknesses of 1 to 12 μm and 1 to 8 μm. The film thickness can be measured using an electronic micrometer (e.g., manufactured by Anritsu Corporation).

[0157] <Absorbance of Light-Absorbing Layer> In the light-absorbing layer, the maximum absorbance of the quencher-containing dipyrromethene dye is usually preferably 0.01 to 1, and more preferably 0.1 to 0.6. In the light-absorbing layer, the absorbance of the quencher-containing dipyrromethene dye can be adjusted by the type and amount of the quencher-containing dipyrromethene dye added (the content in the light-absorbing layer), etc.

[0158] <Moisture Content of Light-Absorbing Layer> From the viewpoint of durability, the moisture content of the light-absorbing layer is preferably 0.5% by mass or less, and more preferably 0.3% by mass or less, regardless of the film thickness, under conditions of 25°C and a relative humidity of 80%. In this specification, the moisture content of the light-absorbing layer can be measured using a sample with a thicker film thickness as necessary. After conditioning the sample for 24 hours or more, the moisture content is measured by the Karl Fischer method using a moisture meter and a sample drying device (for example, "CA-03" and "VA-05" (both manufactured by Mitsubishi Chemical Corporation)), and the moisture content can be calculated by dividing the moisture content (g) by the sample mass (g, including the moisture content).

[0159] <Glass Transition Temperature (Tg) of Light-Absorbing Layer> The glass transition temperature of the light-absorbing layer is preferably 50 to 140°C, more preferably 60 to 130°C, and even more preferably 70 to 120°C. When the glass transition temperature is equal to or higher than the preferred lower limit, deterioration during high-temperature use can be suppressed. When the glass transition temperature is equal to or lower than the preferred upper limit, the organic solvent used in the coating liquid can be prevented from remaining in the light-absorbing layer. The glass transition temperature of the light-absorbing layer can be measured by the following method. In a differential scanning calorimeter (X-DSC7000 (manufactured by IT Measurement & Control Co., Ltd.)), 20 mg of the light-absorbing layer is placed in a measuring pan, and the pan is heated from 30°C to 120°C at a rate of 10°C / min in a nitrogen stream, maintained at this temperature for 15 minutes, and then cooled to 30°C at a rate of -20°C / min. Thereafter, the pan is heated again from 30°C to 250°C at a rate of 10°C / min, and the temperature at which the baseline begins to deviate from the low temperature side is taken as the glass transition temperature Tg. The glass transition temperature of the light absorbing layer can be adjusted by mixing two or more polymers having different glass transition temperatures, or by changing the amount of a low molecular weight compound such as an anti-fading agent added.

[0160] <Treatment of Light-Absorbing Layer> The light-absorbing layer may be subjected to a hydrophilization treatment such as a glow discharge treatment, a corona discharge treatment, or an alkali saponification treatment, with a corona discharge treatment being preferred. In the present invention, it is also preferred to use the light-absorbing layer after the hydrophilization treatment has been performed on the layer to be bonded to a polarizer. Note that the bonding to the polarizer may be performed via an adhesive layer described below. It is also preferred to apply the methods disclosed in JP-A-6-94915 or JP-A-6-118232.

[0161] The obtained film may be subjected to a heat treatment step, a superheated steam contact step, an organic solvent contact step, etc., as required. In addition, a surface treatment may be appropriately performed.

[0162] [Polarizing Plate] The polarizing plate of the present invention includes the polarizing plate protective film of the present invention. The polarizing plate of the present invention preferably has a polarizer and polarizing plate protective films on both sides of the polarizer, and the polarizing plate protective film of the present invention is provided on at least one side of the polarizer. When the polarizing plate protective film of the present invention is provided on only one side of the polarizer, a conventional polarizing plate protective film may be provided on the side of the polarizer opposite to the side on which the polarizing plate protective film of the present invention is provided. The polarizing plate protective film may be provided directly on the polarizer so as to be in contact with the polarizer, or may be provided via an adhesive layer or the like, which will be described later.

[0163] -Performance of Polarizing Plate- The polarizing plate used in the present invention preferably has a polarization degree of 99.95% or more, more preferably 99.97%, and even more preferably 99.99% or more. In the present invention, the polarization degree of the polarizing plate is calculated by calculating a polarization degree spectrum from the crossed transmittance and parallel transmittance measured at wavelengths of 380 to 700 nm using an automatic polarizing film measuring device (for example, VAP-7070 manufactured by JASCO Corporation) using the following formula, and further calculating the weighted average of the light source (auxiliary illuminant C) and the CIE (Commission Internationale de l'Eclairage) standard relative luminous efficiency (Y): Polarization degree (%) = [(parallel transmittance - crossed transmittance) / (crossed transmittance + parallel transmittance)] １／２ ×100 The degree of polarization can be measured as follows. Two samples (5 cm × 5 cm) are prepared by attaching a polarizing plate to glass via an adhesive. The crossed transmittance and parallel transmittance are measured by setting the glass side of the sample facing the light source. Measurements are taken for two samples, and the average values ​​are taken as the crossed transmittance and parallel transmittance, respectively. When investigating the effect of a polarizing plate protective film on the degree of polarization, the polarizing plate protective film to be evaluated is usually placed and attached on the glass side. Other preferable optical properties of the polarizing plate used in the present invention are described in paragraphs

[0238] to

[0255] of JP 2007-086748 A, and it is preferable that these properties be satisfied.

[0164] Shape and Configuration—The shape of the polarizing plate of the present invention includes not only polarizing plates in the form of film pieces cut to a size that can be directly incorporated into a liquid crystal display device, but also polarizing plates produced in a long form by continuous production and wound up into a roll (e.g., a roll length of 2,500 m or more or 3,900 m or more). For use in large-screen liquid crystal displays, the width of the polarizing plate is preferably 1,470 mm or more. The polarizing plate of the present invention is also preferably configured by laminating a separate film to one surface of the polarizing plate in addition to a polarizer and at least one polarizing plate protective film of the present invention. The separate film is used to protect the polarizing plate during shipping, product inspection, etc. The separate film is used to cover the pressure-sensitive adhesive layer provided for laminating the polarizing plate to a liquid crystal cell, and is used on the side of the polarizing plate that will be laminated to the liquid crystal cell.

[0165] [Polarizer] The polarizer that can be used in the polarizing plate of the present invention is preferably composed of polyvinyl alcohol (PVA) and dichroic molecules, but as described in JP-A-11-248937, a polyvinylene-based polarizer can also be used in which a polyene structure is generated by dehydrating and dechlorinating PVA or polyvinyl chloride and then oriented.

[0166] The thickness of the polarizer film before stretching is not particularly limited, and from the viewpoints of film retention stability and stretching uniformity, the thickness is preferably 1 μm to 1 mm, and more preferably 5 to 200 μm. Alternatively, as described in JP-A-2002-236212, a thin PVA film may be used that generates a stress of 10 N or less when stretched 4 to 6 times in water.

[0167] -Method for producing polarizer- The method for producing a polarizer is not particularly limited, but for example, it is preferable to form a film from the PVA and then introduce dichroic molecules to form a polarizer. The PVA film can be produced by referring to the methods described in paragraphs

[0213] to

[0237] of JP 2007-86748 A, Japanese Patent No. 3342516, JP 09-328593 A, JP 2001-302817 A, JP 2002-144401 A, etc.

[0168] (Method of Laminating Polarizer and Polarizing Plate Protective Film) The polarizing plate of the present invention is produced by laminating (stacking) the polarizing plate protective film of the present invention on at least one surface of the polarizer, and may be produced by laminating a conventional polarizing plate protective film on the surface opposite to the surface having the polarizing plate protective film of the present invention. It is preferable to produce the polarizing plate by a method in which the polarizing plate protective film is alkali-treated and then laminated to both surfaces of a polarizer produced by immersing and stretching a polyvinyl alcohol film in an iodine solution using an adhesive such as an aqueous solution of fully saponified polyvinyl alcohol.

[0169] In the polarizing plate of the present invention, the polarizing plate protective film is preferably attached to the polarizer so that the transmission axis of the polarizer and the slow axis of the polarizing plate protective film are substantially parallel, perpendicular, or at 45°. The slow axis can be measured by various known methods, for example, using a birefringence meter (KOBRADH, manufactured by Oji Scientific Instruments). Here, "substantially parallel" means that the direction of the principal refractive index nx of the polarizing plate protective film and the direction of the transmission axis of the polarizing plate intersect at an angle of ±5° or less, preferably at an angle of ±1° or less, and more preferably at an angle of ±0.5° or less. An intersecting angle of 1° or less is preferable because the polarization performance under crossed Nicol polarizing plate conditions is less likely to decrease and light leakage is less likely to occur. The direction of the principal refractive index nx and the direction of the transmission axis being orthogonal or 45° to each other means that the angle at which the direction of the principal refractive index nx and the direction of the transmission axis intersect is within a range of ±5° from the exact angle related to orthogonality and 45°, and the error from the exact angle is preferably within a range of ±1°, and more preferably within a range of ±0.5°.

[0170] [Adhesive Layer] The polarizing plate of the present invention is preferably a polarizing plate obtained by bonding the polarizing plate protective film and the polarizer via an adhesive layer. The thickness of the adhesive layer is typically 1 to 10,000 nm, preferably 30 to 5,000 nm, and more preferably 50 to 3,000 nm. By adjusting the thickness of the adhesive layer within the above range, adhesion between the polarizing plate protective film and the polarizer can be ensured and deformation failure can be suppressed. The adhesive layer in the polarizing plate of the present invention preferably contains a water-soluble material. Specifically, the surface-treated surface of the polarizing plate protective film used in the polarizing plate of the present invention can be directly bonded to one or both sides of the polarizer using an adhesive composed of an aqueous solution of a polyvinyl alcohol-based resin. As the adhesive, an aqueous solution of a polyvinyl alcohol-based adhesive such as polyvinyl alcohol or polyvinyl acetal (e.g., polyvinyl butyral), or a photocurable adhesive can be used, with an aqueous solution of fully saponified polyvinyl alcohol being the most preferred. As the photocurable adhesive (adhesive that cures upon irradiation with light), any photocurable adhesive commonly used for bonding a polarizer and a polarizing plate protective film can be used without any particular limitation, and preferred examples include the photocurable adhesives described in paragraphs 0375 to 0416 of WO 2019 / 066043.

[0171] Furthermore, a pressure-sensitive adhesive layer can be applied to the surface of the polarizer protective film in the polarizer of the present invention. The pressure-sensitive adhesive layer can be a layer made of a pressure-sensitive adhesive composition containing a base polymer such as a (meth)acrylic resin, a styrene resin, or a silicone resin, to which a crosslinking agent such as an isocyanate compound, an epoxy compound, or an aziridine compound has been added. The polarizer of the present invention can be attached to another layer (preferably a liquid crystal cell) in a liquid crystal display device via the pressure-sensitive adhesive layer. The pressure-sensitive adhesive layer can preferably be the same as that described below for pressure-sensitive adhesive layers in liquid crystal display devices.

[0172] The polarizing plate protective film of the present invention may further be laminated with any optical film as long as the effects of the present invention are not impaired. The optical properties and materials of the optional optical film are not particularly limited, but a film containing (or having as its main component) at least one of cellulose ester resin, acrylic resin, cyclic olefin resin, and polyethylene terephthalate resin can be preferably used. An optically isotropic film or an optically anisotropic retardation film may be used. As the optional optical film containing a cellulose ester resin, for example, Fujitac TD80UL (manufactured by Fujifilm Corporation) can be used. Examples of the optical film containing an acrylic resin include an optical film containing a (meth)acrylic resin containing a styrene-based resin as described in Japanese Patent No. 4,570,042, an optical film containing a (meth)acrylic resin having a glutarimide ring structure in the main chain as described in Japanese Patent No. 5,041,532, an optical film containing a (meth)acrylic resin having a lactone ring structure as described in Japanese Patent Laid-Open No. 2009-122664, and an optical film containing a (meth)acrylic resin having a glutaric anhydride unit as described in Japanese Patent Laid-Open No. 2009-139754. Examples of the optical film containing a cyclic olefin resin include a cyclic olefin resin film as described in paragraph

[0029] and subsequent paragraphs of Japanese Patent Laid-Open No. 2009-237376, and a cyclic olefin resin film containing an additive that reduces Rth as described in Japanese Patent No. 4,881,827 and Japanese Patent Laid-Open No. 2008-063536.

[0173] The polarizer protective film of the present invention contains a dipyrromethene dye containing a quencher, which exhibits excellent absorption tailing and light fastness, and therefore, in the liquid crystal display device of the present invention, the dipyrromethene dye containing a quencher in the light absorbing layer of the polarizer protective film constituting the film suppresses unnecessary absorption of display light of the liquid crystal display, thereby improving the transmittance of display light of the liquid crystal display and exhibiting excellent light fastness. Therefore, by applying the polarizer protective film of the present invention, in which the combination and contents of dyes contained in the light absorbing layer are adjusted, to the liquid crystal display device of the present invention, it is possible to expand the color gamut while suppressing a decrease in brightness, and further, the dipyrromethene dye containing a quencher in the light absorbing layer improves the transmittance of display light of the liquid crystal display and exhibits excellent light fastness.

[0174] [Liquid Crystal Display Device] The liquid crystal display device of the present invention includes at least one polarizing plate of the present invention. As long as the liquid crystal display device of the present invention includes the polarizing plate of the present invention, the other configurations of commonly used liquid crystal display devices can be used without any particular limitation. The liquid crystal display device of the present invention preferably includes a configuration in which the polarizing plate of the present invention is bonded to a liquid crystal cell, and more preferably includes a configuration in which the polarizing plate of the present invention is bonded to a liquid crystal cell via a pressure-sensitive adhesive layer.

[0175] FIG. 1 is a schematic diagram illustrating an example of a liquid crystal display device of the present invention. In FIG. 1, the liquid crystal display device 10 comprises a liquid crystal cell having a liquid crystal layer 5 and a liquid crystal cell upper electrode substrate 3 and a liquid crystal cell lower electrode substrate 6 disposed above and below the liquid crystal layer 5, and an upper polarizing plate 1 and a lower polarizing plate 8 disposed on both sides of the liquid crystal cell. A color filter layer may be laminated on the upper electrode substrate 3 or the lower electrode substrate 6. A backlight unit B is disposed on the back of the liquid crystal display device 10. Light-emitting diodes, laser diodes, electroluminescent elements, etc. can be used as the light source for the backlight unit B, but light-emitting diodes (LEDs) are preferred from the perspective of brightness. Among these, a white LED combining a blue LED with a yellow phosphor, or a white LED combining a blue LED, a green LED, and a red LED, is preferred from the perspective of improving color reproducibility when combined with the polarizing plate of the present invention. A light source combining a blue LED with an optical element containing quantum dots is also preferred.

[0176] The upper polarizing plate 1 and the lower polarizing plate 8 each have a laminated structure in which a polarizer is sandwiched between two polarizing plate protective films. In the liquid crystal display device 10 of the present invention, at least one of the polarizing plates is the polarizing plate of the present invention. The polarizing plate protective film of the present invention may be disposed between the liquid crystal cell and the polarizer, or may be disposed on the side of the polarizer opposite to the side on which the liquid crystal cell is located. It is preferable that the polarizer is incorporated into the liquid crystal display device of the present invention so that the polarizer is located on the viewer's side of the polarizing plate protective film of the present invention. For example, the polarizing plate protective film of the present invention is preferably disposed between the liquid crystal cell upper electrode substrate 3 and the polarizer in the upper polarizing plate 1. The liquid crystal display device 10 includes a direct-view type, an image projection type, and an optical modulation type. It is also preferable that the liquid crystal display device be an active matrix liquid crystal display device using three-terminal or two-terminal semiconductor elements such as TFTs (Thin Film Transistors) or MIMs (Metal Insulator Metals). It is also preferable that the liquid crystal display device be a passive matrix liquid crystal display device, typified by the STN (Super Twisted Nematic) mode, known as time-division driving. Furthermore, an IPS (In Plane Switching) mode liquid crystal display device described in paragraphs 0128 to 0136 of JP-A-2010-102296 is also a preferred embodiment of the liquid crystal display device of the present invention.

[0177] [Adhesive layer] In the liquid crystal display device of the present invention, the polarizing plate of the present invention is preferably bonded to the liquid crystal cell via an adhesive layer, and more preferably the surface of the polarizing plate of the present invention on the protective film side is bonded to the liquid crystal cell via an adhesive layer. As the adhesive layer, the descriptions relating to the adhesive layer and the adhesive composition used for the adhesive layer in the OLED display device described in

[0296] to

[0347] of WO 2021 / 014973 can be applied as is.

[0178] The method for forming the pressure-sensitive adhesive layer is not particularly limited, and examples thereof include a method in which a pressure-sensitive adhesive composition is applied to the polarizing plate of the present invention using a conventional means such as a bar coater, followed by drying and curing; a method in which the pressure-sensitive adhesive composition is first applied to the surface of a release substrate, dried, and then the pressure-sensitive adhesive layer is transferred to the polarizing plate of the present invention using the release substrate, followed by aging and curing. The release substrate is not particularly limited, and any release substrate can be used, such as the substrate film used in the above-mentioned method for producing a light-absorbing layer. In addition, the conditions for application, drying, aging, and curing can also be appropriately adjusted based on conventional methods.

[0179] The present invention will be described in more detail below based on examples. The materials, amounts used, ratios, processing details, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the examples shown below. In the following examples, "parts" and "%" representing the composition are based on mass unless otherwise specified. Room temperature means 25°C. In addition, λ ｍａｘ means the maximum absorption wavelength showing the maximum absorbance.

[0180] [Preparation of Polarizing Plate Protective Film (Polarizing Plate Protective Film)] The materials used in preparing the polarizing plate protective film are as follows. <Matrix Resin (Resin)> (Resin 1) A benzyl methacrylate-methacrylic acid random copolymer (manufactured by Fujikura Chemical Industries, Ltd., ACRYBASE FF-187 (trade name), methacrylic acid content 30 mol%, mass average molecular weight 27,500) was used as Resin 1. (Resin 2) An oxazoline group-containing reactive polystyrene resin (manufactured by Nippon Shokubai Co., Ltd., EPOCROS RPS-1005 (trade name), mass average molecular weight 160,000) was used as Resin 2.

[0181] <Dye> The dyes used were as follows: ｍａｘ is the λ value of each dye in a polarizing plate protective film, measured for a polarizing plate protective film having a light absorbing layer laminated on a substrate under the conditions described in the section below [Measurement of transmittance and calculation of absorption maximum value]. ｍａｘ In addition, Me represents a methyl group, and Et represents an ethyl group.

[0182] The free energy change of the dye B-1, as defined in claim 1 of JP-A No. 2023-101372, is −1.8 kcal / mol.

[0183] Pyrromethene 546 (manufactured by Tokyo Chemical Industry Co., Ltd., boron dipyrromethene dye, λ ｍａｘ = 501 nm) was used as dye R-1.

[0184] FDB-002 (trade name, manufactured by Yamada Chemical Industry Co., Ltd., porphyrin vanadium complex dye, λ ｍａｘ = 432 nm)

[0185] Exemplary compound (G-1) described in JP-A No. 2023-051753 was used as dye R-3.

[0186] Compound 1 described in Table 1 of JP-A No. 2023-051753 was used as dye R-4.

[0187] The pyrrole methine dye (λ ｍａｘ = 427 nm) was used as dye A-1.

[0188] (Adhesion-improving resin component 1) A boronic acid ester group-containing copolymer (AD-19) composed of the following components was used as adhesion-improving resin component 1. The content ratios of the following components are based on mass.

[0189] (Substrate 1) Cellulose acylate film (manufactured by Fujifilm Corporation, product name: ZRD40SL)

[0190] <1-1. Production of Polarizing Plate Protective Film No. 1> (1) Preparation of Light-Absorbing Layer-Forming Liquid The components were mixed in the composition shown below to prepare light-absorbing layer-forming liquid (composition) Ba-1. ------------------------------------------------ Composition of Light-Absorbing Layer-Forming Liquid Ba-1 ------------------------------------------------ Resin 1 15.9 parts by mass Resin 2 80.0 parts by mass Adhesion-improving resin component 1 0.90 parts by mass Dye B-1 3.22 parts by mass Toluene (solvent) 396.7 parts by mass Cyclohexanone (solvent) 56.7 parts by mass Isopropyl alcohol (solvent) 113.3 parts by mass

[0191] Subsequently, the obtained light-absorbing layer forming solution Ba-1 was filtered using a filter paper (#63, manufactured by Toyo Roshi Kaisha, Ltd.) having an absolute filtration accuracy of 10 μm, and further filtered using a sintered metal filter (trade name: Pall Filter PMF, media code: FH025, manufactured by Pall Corporation) having an absolute filtration accuracy of 2.5 μm.

[0192] (2) Preparation of Polarizing Plate Protective Film The light-absorbing layer-forming solution Ba-1 after the filtration treatment was applied to the substrate 1 using a bar coater so that the film thickness after drying would be 2.2 μm, and then dried at 130° C. to prepare a polarizing plate protective film No. 1 in which a light-absorbing layer was laminated on the substrate 1.

[0193] <1-2. Preparation of Polarizing Plate Protective Films No. 2 to 5 and c1 to c6> Polarizing plate protective films No. 2 to 5 and c1 to c6 were prepared in the same manner as polarizing plate protective film No. 1, except that the type and amount of dye used in preparing polarizing plate protective film No. 1 were changed as shown in Table 3 below. When changing the amount of dye used, the contents of resin 1 and resin 2 were changed while keeping the content ratio of resin 1 and resin 2 constant, so that the total content of resin 1, resin 2, adhesion-improving resin component 1, and dye was 100 parts by mass. Polarizing plate protective films No. 1 to 5 are polarizing plate protective films (polarizing plate protective films) of the present invention, and polarizing plate protective films No. c1 to c6 are polarizing plate protective films (polarizing plate protective films) for comparison.

[0194] [Measurement of transmittance, calculation of absorption maximum value, and 10% value width] The polarizer protective film obtained was attached to a glass plate with a commercially available acrylate-based adhesive, with the substrate 1 side of the polarizer protective film facing the glass, to obtain a sample for measuring the polarization degree. Furthermore, a reference polarizer protective film prepared in the same manner except that no dye was contained in the polarizer protective film was attached to the glass with an acrylate-based adhesive to obtain a reference sample for measuring the polarization degree. The single-plate transmittance of these polarizer protective film Nos. 1 to 5 and c1 to c6 samples for measuring the polarization degree was measured in the same manner as for the polarizers described below, and Ab ｘ (λ)-Ab ０ The absorbance difference (λ) was calculated, and the maximum value of this absorbance difference was defined as the absorption maximum. Furthermore, at the absorption peak of the dye shown in the Dye B column in Table 3, the difference between the two wavelengths showing 10% of the absorbance of the absorption maximum (100%) (10% value width) was read. The 10% value width of Dye B is shown in the table.

[0195] <2-1. Preparation of Polarizing Plate No. 101> (1) Saponification Treatment of Polarizing Plate Protective Film A commercially available cellulose triacetate film (trade name: Fujitac TG60UL, manufactured by Fujifilm Corporation) was immersed in a 2.3 mol / L aqueous sodium hydroxide solution at 55°C for 3 minutes. It was washed in a water washing bath at room temperature and neutralized with 0.05 mol / L sulfuric acid at 30°C. It was washed again in a water washing bath at room temperature and further dried with hot air at 100°C. In this way, the surface of the cellulose triacetate film was saponified.

[0196] (2) Preparation of Polarizing Plate A polarizer was prepared by adsorbing iodine onto a stretched polyvinyl alcohol film. The light-absorbing layer side of Polarizing Plate Protective Film No. 1 was attached to one side of the polarizer using a 3% by mass aqueous solution of polyvinyl alcohol (manufactured by Kuraray Co., Ltd., product name: PVA-117H). Furthermore, a cellulose triacetate film (product name: Fujitac TG60UL, manufactured by Fujifilm Corporation) that had been saponified as described above was attached to the surface of the polarizer opposite to the side to which Polarizing Plate Protective Film No. 1 was attached using a 3% by mass aqueous solution of polyvinyl alcohol (manufactured by Kuraray Co., Ltd., product name: PVA-117H). Subsequently, after drying at 70°C, a commercially available acrylate-based pressure-sensitive adhesive was applied to the substrate 1 side of Polarizing Plate Protective Film No. 1 to form an acrylate-based pressure-sensitive adhesive / Polarizing Plate Protective Film No. A polarizing plate No. 101 was prepared by laminating a polarizing plate No. 1 (inner polarizing plate protective film) / a polarizer / a cellulose triacetate film (outer polarizing plate protective film) in this order.

[0197] <2-2. Preparation of Polarizing Plates Nos. 102 to 105 and c11 to c16> Polarizing plate Nos. 102 to 105 and c11 to c16 were prepared in the same manner as in the preparation of polarizing plate No. 101, except that polarizing plate protective film Nos. 2 to 5 and c1 to c6 were used instead of polarizing plate protective film No. 1. Polarizing plate Nos. 101 to 105 are polarizing plates of the present invention, and polarizing plate Nos. c11 to c16 are polarizing plates for comparison.

[0198] [Transmittance Measurement] The degree of polarization of the resulting polarizing plates (5 cm long x 5 cm wide) was measured. The polarizing plates were attached to glass with the polarizing plate protective films No. 1 to 5 and c1 to c6 facing the glass via an acrylate-based adhesive, to obtain samples for polarization measurement. A reference polarizing plate, prepared in the same manner except that no dye was contained in the polarizing plate protective film, was attached via an acrylate-based adhesive to obtain reference samples for polarization measurement. These samples were placed in an automatic polarizing film measuring device VAP-7070 (product name) manufactured by JASCO Corporation, with the glass side of the sample facing the light source, and the single-plate transmittance, cross transmittance, and parallel transmittance were measured in 1-nm increments in the wavelength range of 380 nm to 700 nm. (Calculation of Degree of Polarization) The degree of polarization spectrum was calculated from the measured values ​​of the orthogonal transmittance and parallel transmittance according to the following formula, and the degree of polarization was calculated by calculating a weighted average of the light source (auxiliary illuminant C) and the CIE (Commission Internationale de l'Eclairage) standard luminous efficiency (Y), and the degree of polarization was evaluated according to the following criteria: Degree of polarization (%) = [(parallel transmittance - orthogonal transmittance) / (orthogonal transmittance + parallel transmittance)] １／２ ×100 - Evaluation criteria (degree of polarization) - A: The degree of polarization is 99.95% or more. B: The degree of polarization is 99.90% or more and less than 99.95%. C: The degree of polarization is less than 99.90%. (Calculation of maximum absorption value) The obtained single-plate transmittance was converted into absorbance, and the absorbance Ab of the polarization measurement sample at each wavelength λnm was calculated. ｘ (λ) and the absorbance Ab of a reference polarization measurement sample (using a polarizing plate protective film containing no dye). ０ (λ), Ab ｘ (λ)-Ab ０ The maximum absorbance difference (λ) was defined as the absorption maximum.

[0199] <3-1. Preparation of Laminate No. 201> A commercially available cellulose triacetate film (trade name: Fujitac TG60UL, manufactured by Fujifilm Corporation) was attached to the light absorbing layer side of Polarizing Plate Protective Film No. 1 via a commercially available acrylate-based pressure-sensitive adhesive, thereby preparing Laminate No. 201 in which cellulose triacetate film / acrylate-based pressure-sensitive adhesive / Polarizing Plate Protective Film No. 1 were laminated in this order.

[0200] <3-2. Preparation of Laminates Nos. 202 to 205 and c21 to c26> Laminates Nos. 202 to 205 and c21 to c26 were prepared in the same manner as in the preparation of Laminate No. 201, except that polarizer protective films Nos. 2 to 5 and c1 to c6 were used instead of polarizer protective film No. 1. Laminates Nos. 201 to 205 are laminates containing the polarizer protective film of the present invention, and polarizers Nos. c21 to c26 are laminates containing a polarizer protective film for comparison.

[0201] [Measurement of transmittance and calculation of absorption maximum value] The laminate obtained was attached to a glass plate with the polarizing plate protective film Nos. 1 to 5 and c1 to c6 of the laminate facing the glass via a commercially available acrylate-based adhesive, to obtain a polarization measurement sample. Furthermore, a reference laminate prepared in the same manner except that no dye was contained in the polarizing plate protective film was attached via an acrylate-based adhesive to obtain a reference polarization measurement sample. The single-plate transmittance of these polarization measurement samples of laminate Nos. 201 to 205 and c21 to c26 was measured in the same manner as for the above polarizing plates, and Ab ｘ (λ)-Ab ０ (λ) was calculated to determine the maximum absorption value.

[0202] The obtained polarizing plate protective film, polarizing plate, and laminate were evaluated for light resistance as follows.

[0203] <Light resistance> The polarizing plate protective film, polarizing plate, or laminate prepared above was measured using a Super Xenon Weather Meter SX75 (trade name, manufactured by Suga Test Instruments Co., Ltd., with an integrated illuminance of 150 W / m at a wavelength of 300 nm to 400 nm) ２) was used, and light was irradiated for 40 hours or 134 hours in an environment of 60°C and 50% relative humidity, and the absorption maximum after 40 hours of light irradiation and the absorption maximum after 134 hours of light irradiation were calculated using the method described above for calculating the absorption maximum. For each of the 40-hour light irradiation test and the 134-hour light irradiation test, the retention rate of the absorption maximum after light irradiation was calculated using the following formula, and light resistance was evaluated according to the following criteria: [Retention rate of absorption maximum after light irradiation (%)] = ([Absorption maximum after light irradiation] / [Absorption maximum before light irradiation]) × 100 - Evaluation criteria (light resistance) - A: The retention rate of the absorption maximum after light irradiation is 95% or more. B: The retention rate of the absorption maximum after light irradiation is 85% or more and less than 95%. C: The retention rate of the absorption maximum after light irradiation is 70% or more and less than 85%. D: The retention rate of the maximum absorption value after light irradiation is 40% or more and less than 70%. E: The retention rate of the maximum absorption value after light irradiation is less than 40%. The results are summarized in Tables 1 to 3 below.

[0204]

[0205]

[0206]

[0207] (Notes for the table) Dye amount: This refers to the amount of dye blended in 100 parts by mass of the light absorbing layer, and the unit is parts by mass. Dyes A and B refer to dyes A and B, respectively, that have a main absorption wavelength band in the specific wavelength range described above. "-" indicates that the corresponding dye is not contained. Lightfastness @ 40 hours indicates the evaluation result of lightfastness in a 40-hour light irradiation test, and lightfastness @ 134 hours indicates the evaluation result of lightfastness in a 134-hour light irradiation test.

[0208] The results in Tables 1 to 3 above reveal the following. Polarizing plate Nos. c11 and c12, and polarizing plate protective film Nos. c1 and c2 in laminate Nos. c21 and c22, are not polarizing plate protective films of the present invention in that the light absorbing layer contains dye R-1, a dipyrromethene dye that does not contain a quencher moiety. In these polarizing plate Nos. c11 and c12, laminate Nos. c21 and c22, and polarizing plate protective film Nos. c1 and c2, dye R-1 exhibited poor light resistance under both 40-hour and 134-hour light irradiation conditions. Furthermore, polarizing plate Nos. c13 and c14, and polarizing plate protective film Nos. c3 and c4 in laminate Nos. c23 and c24, are not polarizing plate protective films of the present invention in that the light absorbing layer contains dye R-2, a squarylium dye. These polarizing plate Nos. In the case of c13 and c14, laminates c23 and c24, and polarizer protective films c3 and c4, dye R-2 exhibited poor lightfastness under at least 134 hours of light irradiation, with a 10% bandwidth of 75 nm and poor absorption tailing. In particular, laminate c23 and polarizer protective film c3, which contained only dye R-2 as the dye, received a rating of B in lightfastness under 40 hours of light irradiation, whereas laminate c24 and polarizer protective film c4, which contained dyes R-2 and FDB-002 as dyes, received a rating of C in lightfastness under 40 hours of light irradiation. The combined use of dye R-2 with FDB-002 resulted in a 5% decrease in the retention of the absorption maximum of dye R-2 after 40 hours of light irradiation. Furthermore, polarizer No. c15 and laminate c3 were also poorly rated for lightfastness under 40 hours of light irradiation. Polarizer protective film No. c5 in polarizer No. c25 is different from the polarizer protective film of the present invention in that the light-absorbing layer contains dye R-3, which is a catechol-coordinated dipyrromethene boron complex compound, while polarizer protective film No. c6 in polarizer No. c16 and laminate No. c26 is different from the polarizer protective film of the present invention in that the light-absorbing layer contains dye R-4, which is a dipyrromethene cobalt complex coordinated with two dipyrromethene ligands. These polarizer No. c15, laminate No. c25, and polarizer protective film No. c5 had a 10% peak width of 68 nm, while polarizer No. c16, laminate No. c26, and polarizer protective film No. c6 had a 10% peak width of 66 nm, and all of them exhibited poor absorption tailing.In contrast, in the polarizer protective films Nos. 1 to 5 of the present invention, which are polarizer protective films, and polarizers Nos. 101 to 105 and laminates Nos. 201 to 205 each including these polarizer protective films No. 1 to 5, the quencher-containing dipyrromethene dyes B-1 and B-2 maintained an absorption maximum value of 85% or more after light irradiation under both 40-hour and 134-hour light irradiation conditions, demonstrating excellent light fastness. In addition, Dyes B-1 and B-2, which are dipyrromethene dyes with built-in quenchers, have 10% value widths of 63 nm and 60 nm, respectively, which are narrower than those of Dye R-3, a catechol-coordinated dipyrromethene boron complex compound, and Dye R-4, a dipyrromethene cobalt complex coordinated with two dipyrromethene ligands, used in the above-mentioned Comparative Examples, and provide absorption waveforms with sharp tails. Therefore, even when the polarizer protective film or polarizer of the present invention is applied to a liquid crystal display device, the transmittance of display light can be improved. Furthermore, Polarizers Nos. 102 and 104, Laminates Nos. 202 and 204, and Polarizer Protective Film No. In Examples 2 and 4, when dye B-1 or B-2, a quencher-containing dipyrromethene dye, was used in combination with FDB-002, the decrease in the absorption maximum retention rate of dye B-1 and B-2 after 40 hours of light irradiation was suppressed to less than 1%, and even when two or more dyes with different main absorption wavelength bands were contained, dyes containing quencher-containing dipyrromethene dyes exhibited excellent light fastness. In particular, when the polarizing plate was formed using the polarizing plate protective film of the present invention, dyes B-1 and B-2 exhibited an absorption maximum retention rate of 95% or more after 134 hours of light irradiation, demonstrating excellent light fastness.

[0209] While the present invention has been described in connection with embodiments thereof, we do not intend to limit our invention to any of the details of the description unless otherwise specified, and believe that the claims should be construed broadly without departing from the spirit and scope of the invention as set forth in the appended claims.

[0210] This application claims priority based on Japanese Patent Application No. 2024-109489, filed on July 8, 2024, the contents of which are incorporated herein by reference as part of the present specification.

[0211] REFERENCE SIGNS LIST 1 Upper polarizer 2 Direction of absorption axis of upper polarizer 3 Liquid crystal cell upper electrode substrate 4 Alignment control direction of upper substrate 5 Liquid crystal layer 6 Liquid crystal cell lower electrode substrate 7 Alignment control direction of lower substrate 8 Lower polarizer 9 Direction of absorption axis of lower polarizer B Backlight unit 10 Liquid crystal display device

Claims

1. A polarizing plate protective film comprising a light absorbing layer containing a resin and a dye containing a quencher-containing dipyrromethene dye.

2. The polarizer protective film according to claim 1, wherein the dyes comprise two or more dyes having different main absorption wavelength bands, with the proviso that at least one of the two or more dyes having different main absorption wavelength bands is the quencher-containing dipyrromethene dye.

3. The polarizing plate protective film according to claim 1, wherein the dipyrromethene dye having a built-in quencher is represented by the following general formula (P): In the above formula, R １ ~R ６ represents a hydrogen atom or a substituent. ７ and R ８ represents a fluorine atom. ９ represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, or an electron-donating quencher moiety. １ ~R ６ and R ９ At least one of the groups comprises an electron-donating quencher moiety.

4. The polarizing plate protective film described in claim 3, wherein the electron-donating quencher moiety is a ferrocenyl group represented by the following general formula (2M), or an aryl group having at least one of an amino group, an alkoxy group, a hydroxy group, and a nitro group as a substituent. In the above formula, L represents a single bond or a divalent linking group that is not conjugated with the dipyrromethene dye in the quencher-containing dipyrromethene dye. １ｍ ~R ９ｍ represents a hydrogen atom or a substituent. M is an atom that can constitute a metallocene compound, and represents Fe, Co, Ni, Ti, Cu, Zn, Zr, Cr, Mo, Os, Mn, Ru, Sn, Pd, Rh, V, or Pt. * represents a bonding site with the dipyrromethene dye in the quencher-incorporated dipyrromethene dye.

5. The L is a single bond or an arylene group having 6 to 12 carbon atoms, and the R １ｍ ~R ９ｍ 5. The polarizer protective film according to claim 4, wherein is a hydrogen atom, a halogen atom, an alkyl group, an acyl group, or an alkoxy group, and M is Fe.

6. A polarizing plate comprising the polarizing plate protective film according to any one of claims 1 to 5.

7. A liquid crystal display device comprising the polarizing plate according to claim 6.

8. The liquid crystal display device according to claim 7, wherein the polarizing plate protective film is disposed between the liquid crystal cell and the polarizer.

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