KR20230089286A - Achromatic circular polarizer film and antireflection film for display containing with the same - Google Patents

Abstract

The present invention relates to an achromatic circularly polarized film, and more specific, to an achromatic circularly polarized film equipped with a retardation film that prevents or minimizes disclination due to lack of orientation while making the thickness of the retardation film in the circularly polarizing film thinner than before, and a display which applies the same as an anti-reflection film against external light.

Description

Achromatic circular polarizing film and antireflection film for display including the same {ACHROMATIC CIRCULAR POLARIZER FILM AND ANTIREFLECTION FILM FOR DISPLAY CONTAINING WITH THE SAME}

The present invention relates to an achromatic circular polarizing film that can be applied as an external light antireflection film, a retardation film applied thereto, and a display, optical device, etc. to which the achromatic circular polarizing film is applied as an antireflection film.

In a display where light is emitted from a highly reflective surface such as OLED (Organic Light Emitting Diodes) or Micro LED (Micro Light Emitting Diodes, or mini LED), when external light is incident on the display panel, the light incident from the outside is reflected inside the display. There is a problem in that an optical signal emitted from the display is weakened due to reflection, resulting in performance degradation.

In order to solve this problem, a high-end display uses a circular polarizing plate having the same function as that shown in FIG. 1 . According to the structure shown in FIG. 1, light incident from the outside is changed into left circularly polarized light by the circular polarizing plate and is incident, and the polarization direction is changed into right circularly polarized light after being reflected by the reflector. The right-circularly polarized light is again extinguished by the left-circularly polarized plate. At this time, the observer observes only the optical signal emitted from the display or optical element as the external light is extinguished. That is, optical signal interference caused by external light is removed to improve the performance of the display or optical element.

In general, the circular polarization film applied as an antireflection film consists of a linear polarizer and a retardation film. If the retardation film used at this time is formed as a regular dispersion film, color characteristics deteriorate due to retardation deviation at long and short wavelengths than ideal QWP. In addition, there is a problem in that light leakage and color characteristic deterioration due to phase difference deviation in the viewing angle appear.

In order to solve these problems of the existing circular polarization film, a reverse dispersion film was applied as a retardation film, but the reverse dispersion film had a small refractive index anisotropy (Dn) and had to be formed very thickly, with a thickness of 3 μm or more. . In addition, a relatively large thickness reverse dispersion film requires a large orientation force during rubbing orientation or optical orientation, and when the orientation force is low, disclination, a kind of defect, occurs and reflects external light on the display. There is a problem that reduces performance.

Korean Patent Publication No. 10-2014-0077580 (published on 2014.06.24.)

The present invention has optimal optical properties for preventing or minimizing disclination due to lack of orientation while lowering the thickness of a reverse wavelength dispersion quarter-wavelength film among circular polarization films applied as an external light antireflection film. It is intended to provide a circular polarizing film to which a retardation film is applied and an antireflection film for a display having the same.

The achromatic circular polarizing film of the present invention for solving the above problems includes a retardation film and a polarizer on top of the retardation film, and the retardation film includes a quarter-wavelength film (hereinafter referred to as "QWP film").

As a preferred embodiment of the present invention, the retardation film includes a liquid crystal layer and an optical alignment layer.

As a preferred embodiment of the present invention, the quarter wave film may be a reverse wavelength dispersion quarter wave film (hereinafter referred to as "r-AQWP") or a flat wavelength dispersion quarter wave film.

As a preferred embodiment of the present invention, in the achromatic circular polarizing film of the present invention, an optical axis angle between the polarizer and the retardation film may be 20° to 40°.

As a preferred embodiment of the present invention, the achromatic circular polarizing film of the present invention may further include a C plate layer on the other side of the retardation film on which the polarizer is stacked, or a C plate layer between the polarizer and the retardation film. .

As a preferred embodiment of the present invention, in the achromatic circular polarizing film of the present invention, the retardation film may further include a half-wavelength film (hereinafter referred to as "HWP") below or above the QWP film.

As a preferred embodiment of the present invention, the QWP film may include a quarter-wavelength film including a liquid crystal having a twist angle of 40° to 70°.

As a preferred embodiment of the present invention, the QWP film may satisfy the retardation on the optical axis of Equations 1 and 2 below.

[Equation 1]

0.825 ≤ α ≤ 1.045

[Equation 2]

0.965 ≤ β ≤ 1.205

In Equations 1 and 2, α is R ₄₅₀ /R ₅₅₀ , β is R ₆₅₀ /R ₅₅₀ , R ₄₅₀ denotes an optical axial retardation at a light wavelength of 450 nm, R ₅₅₀ denotes an optical axial retardation at a light wavelength of 450 nm, and R ₆₅₀ denotes an optical axial retardation at a light wavelength of 650 nm.

As a preferred embodiment of the present invention, the QWP film may have an optical axis retardation (R ₅₅₀ ) of 120 to 150 nm at a wavelength of 450 nm.

As a preferred embodiment of the present invention, the QWP film may have a thickness of 2.5 to 3.8 μm.

As a preferred embodiment of the present invention, the QWP film includes a liquid crystal layer and an alignment layer, and the liquid crystal layer may be formed of a liquid crystal resin including a polymerizable liquid crystal compound and a chiral dopant.

As a preferred embodiment of the present invention, the polymerizable liquid crystal compound may include a reverse wavelength liquid crystal compound having a refractive index of Equation 3 below and a forward wavelength liquid crystal compound having a refractive index of Equation 4 below.

[Equation 3]

0.040 ≤ │Δn ₁ │ ≤ 0.065

[Equation 4]

0.100 ≤ │Δn ₂ │ ≤ 0.150

In Equations 3 and 4, Δn ₁ and Δn ₂ respectively mean the difference between the refractive index of extraordinary light (n _e ) and the refractive index of normal light (n _o ).

As a preferred embodiment of the present invention, the polymerizable liquid crystal compound may include the reverse wavelength liquid crystal compound and the forward wavelength liquid crystal compound in a weight ratio of 1:0.05 to 0.55.

As a preferred embodiment of the present invention, the photo-alignment layer includes an photo-alignment compound, and the photo-alignment compound includes a liquid crystal photo-alignment agent characterized in that it includes a polymer including a repeating unit represented by Formula 1 below. can

[Formula 1]

또는

이며, R⁴는 C₁~C₁₀의 직쇄형 알킬기, C₃~C₁₀의 분쇄형 알킬기, 탄소원자 1개 이상이 헤테로 원자로 치환된 C₂~C₁₀의 직쇄형 헤테로 알킬기 또는 탄소원자 1개 이상이 헤테로 원자로 치환된 C₃~C₁₀의 분쇄형 헤테로 알킬기이고, m은 중합체의 중량평균분자량 1,000 ~ 1,000,000을 만족하는 정수이며, n은 0 내지 20의 정수이고, *는 결합부위를 의미한다.In Formula 1, R ¹ is a hydrogen atom or an alkyl group of C ₁ to C ₃ , A is -OR ³ -, -NHR ³ - or -SR ³ -, and R ³ is a C ₂ to C ₅ linear alkyl group. Ren's group, and R ² is

or

And, R ⁴ is C ₁ ~ C ₁₀ straight-chain alkyl group, C ₃ ~ C ₁₀ branched alkyl group, C ₂ ~ C ₁₀ straight-chain heteroalkyl group in which at least one carbon atom is substituted with a hetero atom, or one carbon atom The above is a C ₃ ~ C ₁₀ branched heteroalkyl group substituted with a hetero atom, m is an integer satisfying the weight average molecular weight of the polymer of 1,000 to 1,000,000, n is an integer from 0 to 20, and * denotes a bonding site. .

As a preferred embodiment of the present invention, the polymer composition of the liquid crystal photoalignment may be a copolymer further including a repeating unit represented by Chemical Formula 1 and a repeating unit represented by Chemical Formula 2 below.

[Formula 2]

In Formula 2, R ¹ is a hydrogen atom or a C ₁ ~ C ₃ alkyl group, and R ⁵ is a C ₁ ~ C ₁₀ straight-chain alkyl group, a C ₃ ~ C ₁₀ branched alkyl group, or a hetero atom having at least one carbon atom. A C ₂ ~ C ₁₀ straight-chain heteroalkyl group substituted with atoms, a C ₃ ~ C ₁₀ branched heteroalkyl group in which at least one carbon atom is substituted with a hetero atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted phenoxy group, or A substituted or unsubstituted N-phenylamino group, and L is an integer of 1 to 20.

As a preferred embodiment of the present invention, the liquid crystal photo-alignment agent may include the photo-alignment compound and a solvent.

As a preferred embodiment of the present invention, the solvent of the liquid crystal photo-alignment agent is one selected from benzene, toluene, ethyl acetate, butyl acetate, tetrahydrofuran (THF), PGMEA (Propylene glycol methyl ether acetate), dichloromethane and chloroform non-polar solvents including the above; and a polar solvent containing at least one selected from cyclopentanone, cyclohexanone, acetone, dimethylformamide (DMF), and acetonitrile; It may include one or more selected from among.

As a preferred embodiment of the present invention, when a chiral dopant is not used in the liquid crystal layer of the QWP film, the QWP film may satisfy the refractive index of Equation 5 below.

[Equation 5]

0.045 ≤ │Δn│ ≤ 0.080

In Equation 4, Δn means the difference between the refractive index of extraordinary light (n _e ) and the refractive index of normal light (n _o ).

As a preferred embodiment of the present invention, the C plate layer may include a homeotropic alignment liquid crystal polymer film and satisfy the refractive index of Equation 6.

[Equation 6]

n _z > n _x ≒ n _y

In Equation 6, n _x is the refractive index in the direction in which the refractive index in the plane in the slow axis direction is the maximum, n _y is the refractive index in the direction orthogonal to the slow axis in the plane and in the plane, and n _z means the refractive index in the thickness direction .

As a preferred embodiment of the present invention, the thickness direction retardation (R _th ) of the C plate layer according to Equation 1 below may be -120 to -30 nm.

[Equation 1]

_Rth = {(n _x +n _y )/2 - n _z }×d

In Equation 1, n _x is the refractive index in the direction in which the refractive index in the plane in the slow axis direction is the maximum, n _y is the refractive index in the direction orthogonal to the slow axis in the plane and in the plane, n _z is the refractive index in the thickness direction, d is is the thickness of the film.

Another object of the present invention relates to a retardation film applied to the achromatic circular polarizing film, and to provide a retardation film including a quarter-wavelength film having a thickness of 2.5 to 3.8 μm and a liquid crystal twist angle of 40° to 70°. .

Another object of the present invention is an antireflection film for a display, including the above-described circularly polarizing film.

As a preferred embodiment of the present invention, the display may be an Organic Light Emitting Diodes (OLED) display or a Micro Light Emitting Diodes (LED) display.

The circular polarizing film of the present invention can prevent or minimize disclination and light leakage on the front and side surfaces due to lack of orientation of the retardation film and improve color balance through the introduction of a specific optical alignment layer and optimization of the liquid crystal layer. , it is possible to provide a circular polarizing film to which a relatively thin retardation film is applied compared to the conventional one. Such a circularly polarizing film of the present invention is suitable for application as an external light antireflection film for OLED displays and micro LED displays requiring flexibility and thinness.

1 is a conceptual diagram explaining the antireflection principle of a conventional circular polarizing film composed of a polarizer and a retardation film.
2A to 2G each show a schematic diagram of the structure of the circularly polarizing film of the present invention.
3 is a polarization microscope measurement photograph of the reverse wavelength dispersion film prepared in Comparative Example 1 (A) and Example 1 (B) performed in Experimental Example 1.

Terms used in the present invention are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "comprise" or "having" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features or It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

In addition, the expression "~ on or ~ on top" or "~ on the bottom" means directionality, not only when the upper and lower components are in direct contact or spaced apart, but also include another component in the middle Including the case where there is, it means directionality.

The structural description of the achromatic circular polarizing film of the present invention is as follows.

As schematically shown in FIG. 2A, the achromatic circular polarizing film 100 of the present invention is applied to the upper part of the display unit (reflection layer) 1.

The achromatic circular polarization film includes a retardation film 10 and a polarizer 20 on top of the retardation film.

The retardation film may be composed of a quarter-wavelength film (hereinafter referred to as "QWP film"), and the QWP film may be a reverse wavelength dispersion quarter-wavelength film (hereinafter referred to as "r-AQWP film") or a flat wavelength quarter-wavelength film. can

In the achromatic circular polarizing film of the present invention, an optical axis angle between the polarizer and the retardation film may be 20 to 40°, preferably 22° to 38°. At this time, if the optical axis angle between the polarizer and the retardation film is less than 20°, there may be a problem of blue shift in color coordinates, and if the optical axis angle between the polarizer and the retardation film exceeds 40°, there may be a red shift in color coordinates. Therefore, it is preferable to combine the optical properties of the polarizer and the retardation film to satisfy the optical axis angle within the above range.

As shown schematically in FIG. 2B, the retardation film of the achromatic circular polarizing film of the present invention may be composed of the QWP film 12 alone, and as shown schematically in FIG. It is referred to as "HWP film", and may be a retardation film in which 14) is laminated.

In addition, as shown in FIGS. 2D and 2F, the achromatic circular polarizing film of the present invention is a structure in which a C plate layer 30 is formed under a retardation film (QWP film alone, or QWP film and HWP film two-layer structure). 2e and 2g, it may be a structure in which the C plate layer 30 is formed between the polarizer and the retardation film (QWP film alone, or QWP film and HWP film two-layer structure).

It is possible to directly attach the polarizer, retardation film, QWP film, HWP film, and C plate layer constituting the achromatic circular polarizing film of the present invention described above without a separate adhesive layer (or adhesive layer) for combining (or integrating) each. And, although not shown in FIG. 2, if necessary, when bonding (or bonding) between at least one layer, a transparent adhesive layer (OCA, Optically Clear Adhesive) or a transparent adhesive layer may be interposed.

The transparent pressure-sensitive adhesive layer may use an acrylic pressure-sensitive adhesive, and the acrylic pressure-sensitive adhesive includes an acrylic polymer having an alkyl (meth)acrylate monomer unit as a main skeleton as a base polymer. The average number of carbon atoms of the alkyl group of the alkyl (meth) acrylate constituting the main skeleton of the acrylic polymer is about 1 to 12, preferably one having 1 to 9 carbon atoms can be used. As specific examples of the alkyl (meth) acrylate, Methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, la There are uryl (meth)acrylates and the like, and these may be used alone or in combination of two or more.

The acrylic polymer may use a polymer or copolymer obtained by polymerizing or copolymerizing monomers to improve adhesion and heat resistance. Preferred examples include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate hydroxyl group-containing monomers such as (4-hydroxymethylcyclohexyl)-methyl acrylate; carboxyl group-containing monomers such as (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; acid anhydride group-containing monomers such as maleic anhydride and itaconic anhydride; caprolactone adducts of acrylic acid; Contains sulfonic acid groups such as styrenesulfonic acid, allylsulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamidepropanesulfonic acid, sulfopropyl(meth)acrylate, and (meth)acryloyloxynaphthalenesulfonic acid monomer; phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate; maleimide, N-cyclohexylmaleimide, N-phenylmaleimide; N-acryloylmorpholine; (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-hexyl(meth)acrylamide, N-methyl(meth)acrylamide, N-butyl (N-substituted) amide monomers such as (meth)acrylamide, N-butyl (meth)acrylamide, N-methylol (meth)acrylamide, and N-methylolpropane (meth)acrylamide; Aminoethyl (meth)acrylate, aminopropyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, t-butylaminoethyl (meth)acrylate, 3-(3-pyrinidyl)propyl (meth)acrylate (meth)acrylic acid alkylaminoalkyl type monomers such as the like; (meth)acrylic acid alkoxyalkyl-based monomers such as methoxyethyl (meth)acrylate and ethoxyethyl (meth)acrylate; and N-(meth)acryloyloxymethylenesuccinimide, N-(meth)acryloyl-6-oxyhexamethylenesuccinimide, N-(meth)acryloyl-8-oxyoctamethylenesuccinimide, succinimide-based monomers such as N-acryloylmorpholine; A polymer or copolymer obtained by polymerizing or copolymerizing one or more monomers selected from the above may be used as the acrylic polymer.

In addition, the achromatic circularly polarizing film of the present invention may further include a protective film on the polarizer.

In addition, the circular polarizing film of the present invention composed of a polarizer and a retardation film may have a front reflectance of 0.002400 or less, preferably 0.001700 to 0.002350, more preferably 0.001700 to 0.002300. In addition, the side reflectivity (q = 50, f = 45 deg) may be 0.012000 or less, preferably 0.004000 to 0.011500, more preferably 0.005000 to 0.011000.

In addition, the circular polarizing film of the present invention composed of a polarizer, a retardation film, and a C plate layer may have a front reflectance of 0.002300 or less, preferably 0.001500 to 0.002300. In addition, the side reflectivity (q = 50, f = 45 deg) may be 0.010000 or less, preferably 0.003000 to 0.009500, more preferably 0.003500 to 0.008500.

Each layer (or film) constituting the achromatic circular polarizing film of the present invention will be described in detail as follows.

[Polarizer]

In the present invention, the polarizer may use a stretched film in which a dye having absorption anisotropy is adsorbed or a film in which a dye having absorption anisotropy is applied and aligned, and a polarizer commercially available in the art may be used.

[Phase difference film]

The retardation film of the present invention includes a liquid crystal layer and an optical alignment layer, and the retardation film has a very thin QWP having a thickness of 2.5 to 3.8 μm, preferably a thickness of 2.70 to 3.60 μm, and more preferably a thickness of 2.85 to 3.50 μm. film can be applied.

In order to apply such a thin QWP film as a retardation film, the QWP film must satisfy the following optical properties to manufacture a circular polarizing film as an antireflection film.

The QWP film used in the present invention satisfies the retardation on the optical axis of Equations 1 and 2 below.

[Equation 1]

0.825 ≤ α ≤ 1.045, preferably 0.900 ≤ α ≤ 0.995, more preferably 0.915 ≤ α ≤ 0.990

[Equation 2]

0.965≤β≤1.205, preferably 0.970≤β≤1.150, more preferably 0.975≤β≤1.050

In Equations 1 and 2 above, α is R ₄₅₀ /R ₅₅₀ , β is R ₆₅₀ /R ₅₅₀ , R ₄₅₀ denotes an optical axial retardation at a light wavelength of 450 nm, R ₅₅₀ denotes an optical axial retardation at a light wavelength of 450 nm, and R ₆₅₀ denotes an optical axial retardation at a light wavelength of 650 nm.

And, the QWP film may be a reverse wavelength dispersion quarter-wavelength film that satisfies α<β.

In addition, the QWP film may be a flat wavelength dispersion quarter-wavelength film that satisfies α≒β.

In addition, the QWP film may have an optical axis retardation (R ₅₅₀ ) of 120 to 150 nm, preferably 125 to 145 nm, and more preferably 130 nm to 143 nm at a wavelength of 550 nm.

In addition, the QWP film includes a liquid crystal having a twist angle of 40° to 70°, preferably a twist angle of 50° to 70°, and more preferably a twist angle of 56° to 68°. Here, the twist angle means the twist angle of the liquid crystal from the bottom of the QWP film to the top when the direction close to the polarizer film is the top of the QWP film and the direction far from the polarizer film is the bottom of the QWP film, based on the polarizer film. . That is, it means the twisted angle of the upper liquid crystal based on the angle O° of the lower liquid crystal of the QWP film.

In addition, when a chiral dopant is not used in the liquid crystal layer of the QWP film, the QWP film may satisfy the refractive index of Equation 5 below.

[Equation 5]

0.045 ≤│Δn│≤ 0.080, preferably 0.048 ≤│Δn│≤ 0.075, more preferably 0.050 ≤│Δn│≤ 0.070

In Equation 5, Δn means the difference between the refractive index of extraordinary light (n _e ) and the refractive index of normal light (n _o ).

The QWP film for satisfying the above-described thickness and optical properties includes a liquid crystal layer formed of a liquid crystal resin containing a polymerizable liquid crystal compound and a chiral dopant, and an alignment layer for liquid crystal alignment. In addition, the alignment may be performed through rubbing alignment or optical alignment.

The polymerizable liquid crystal compound in the liquid crystal resin includes a reverse wavelength liquid crystal compound having a refractive index of Equation 3 below and a forward wavelength liquid crystal compound having a refractive index of Equation 4 below.

[Equation 3]

0.040 ≤│Δn ₁ │≤ 0.065, preferably 0.040 ≤│Δn ₁ │≤ 0.060, more preferably 0.040 ≤│Δn ₁ │≤ 0.048

[Equation 4]

0.100 ≤│Δn ₂ │≤ 0.150, preferably 0.110 ≤│Δn ₂ │≤ 0.150, more preferably 0.120 ≤│Δn ₂ │≤ 0.140

In Equations 3 and 4, Δn ₁ and Δn ₂ respectively mean the difference between the refractive index of extraordinary light (n _e ) and the refractive index of normal light (n _o ).

In addition, the polymerizable liquid crystal compound may include the reverse wavelength liquid crystal and the forward wavelength liquid crystal in a weight ratio of 1:0.05 to 0.55, preferably 1:0.10 to 0.45 weight ratio, more preferably 1:0.15 to 0.35 weight ratio. It can be included in weight ratio. At this time, if the weight ratio of the regular wavelength liquid crystal is less than 0.05, the alignment of the liquid crystal in the QWP film is insufficient and the optical properties cannot be matched with the polarizer, which may cause a linear lattice defect (disclination). Since the value of the retardation on the optical axis (α, β) of the film may not satisfy Equation 1 and/or Equation 2 above, it is recommended to use it within the above range.

Among the polymerizable liquid crystal compounds, one or a mixture of two or more reverse wavelength liquid crystal compounds satisfying the refractive index of Equation 3 may be used as the reverse wavelength liquid crystal.

As the reverse wavelength liquid crystal compound, at least one selected from commercially available nematic liquid crystal compounds and discotic liquid crystal compounds may be used.

As a reverse wavelength liquid crystal compound, the nematic liquid crystal compound is 2-(C ₁ ~C ₅ alkyl)-1,4-phenylenebis(4-(((4-(acryloyloxy)(C ₁ ~C ₅ alkoxy)carbonyl)oxy)benzoate ((2-(C ₁ ~C ₅ alkyl)-1,4-phenylene bis(4-(((4-(acryloyl oxy)(C ₁ ~C ₅ alkoxy) carbonyl)oxy)benzoate); a copolymer in which two or more polymers having one or more functional groups are copolymerized; and/or a disulfonic acid-based compound having a polycyclic structure.

Polymers having at least one functional group are poly(2,2'-disulfo-4,4'-benzidine terephthalamide, poly(2,2'-disulfo-4,4'-benzidine sulfoterephthalamide, poly( para-phenylene sulfoterephthalamide), poly(2-sulfo-1,4-phenylene sulfoterephthalamide), poly(2,2'-disulfo-4,4'-benzidine naphthalene-2,6-dicar Boxamide, poly(disulfobiphenylene-1,2-ethylene-2,2'-disulfobiphenylene), poly(2,2'-disulfobiphenylene-dioxyterephthaloyl), poly((2 ,2'-disulfobiphenyl-2-sulfodioxyterephthaloyl), poly(sulfophenylene-1,2-ethylene-2,2'-disulfobiphenylene), poly(2-sulfophenylene,1 ,2-ethylene-2'-sulfophenylene), poly(2,2'-disulfobiphenyl-2-sulfo-1,4-dioxymethylphenylene), poly(disulfo-quarterphenylethylene), poly( disulfo-terphenylethylene), poly(sulfo-biphenylethylene), poly(disulfo-biphenylethylene), poly(4,9-disulfobenzo[1,2-d;5,4-d'] Bisoxazole-1,7-ethylene), poly(benzo[1,2-d;5,4-d']bisoxazole-1,7-[1,1'-ethane-1,2-diyl- 2,2'-disulfodibenzene]), poly(4,9-disulfobenzo[1,2-d;5,4-d']bisoxazole-1,7-[1,1'-ethane- 1,2-diyl-2,2'-disulfodibenzene]), poly(benzo[1,2-d;4,5-d']bisthiazole-1,7-[1,1'-ethane-1 ,2-diyl-2,2'-disulfodibenzene]), poly(4,9-disulfobenzo[1,2-d;4,5-d']bisthiazole-1,7-[1, 1'-ethane-1,2-diyl-2,2'-disulfodibenzene]), poly(4,4'-dimethylene-1-sulfobiphenyl)-(4,4'-deoxy-1, 1'-disulfobiphenyl)ether) and poly(4,4'-dimethylene-1,1'-sulfobiphenyl)-(4,4'-dioxy-1,1'-disulfobiphenyl)ether) It may include one or more selected from among.

,

,

,

, 또는

일 수 있으며, R, R₁, R₂, R₃, R₄, R₅는 독립적으로, 수소원자, C₁~C₅의 알킬기, -SO₃H, -PO₃H₂, -(CH₂)_mOH (이때, m은 1 ~ 5이다) 또는 -NH₂이다.And, the functional group is -N=N-,

,

,

,

, or

And, R, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ are independently a hydrogen atom, a C ₁ ~ C ₅ alkyl group, -SO ₃ H, -PO ₃ H ₂ , -(CH ₂ ) _m OH (where m is 1 to 5) or -NH ₂ .

The polycyclic disulfonic acid-based compound is 4,4'-(5,5-dioxydibenzo[b,d]thien-3,7-diyl)dibenzenesulfonic acid, dinaphtho[2,3-b: 2',3'-d]furan disulfonic acid, 12H-benzene[b]phenoxazine disulfonic acid, dibenzo[b,i]oxantrene disulfonic acid, benzo[b]naphtho[2',3':5, 6]dioxino[2,3-i]oxantrene disulfonic acid, dibenzo[b,d]chrysene-7,14-dione disulfonic acid and/or 7-(4-sulfophenyl)dibenzo[b, d]thiophene-3-sulfonic acid-5,5-dioxide, wherein the disulfonic acid compound is -Cl, -Br, -NO ₂ , -F, -CF ³ , -CN, -OH, -OCH ₃ , -OC ₂ H ₅ , -OCOCH 3 , -OCN, -SCN, and -NHCOCH ₃ may include one or more substituents selected from one or more.

As a reverse wavelength liquid crystal compound, the discotic liquid crystal compound has negative refractive index anisotropy (uniaxial), for example, a benzene derivative, a cyclohexane derivative, an azacrown-based macrocycle or a phenylacetylene-based macrocycle at the molecular center. It can include a liquid crystal compound having a structure in which a linear alkyl group, an alkoxy group, a substituted benzoyloxy group, or the like is radially substituted as the mother nucleus. In addition, the discotic liquid crystal compound may be one having a polymerizable unsaturated group (eg, an acryloyl group, a methacryloyl group, a vinyl group, an allyl group, etc.) that is cured by heat or light. there is.

Among the polymerizable liquid crystal compounds, the short-wavelength liquid crystal compound may be used by mixing one type or two or more types of short-wavelength liquid crystals that satisfy the refractive index of Equation 4 above.

At least one selected from commercially available nematic liquid crystal compounds and discotic liquid crystal compounds may be used as the long-wavelength liquid crystal compound.

Examples of the short-wavelength liquid crystal include, for example, a short-wavelength liquid crystal compound represented by Formula 1 and/or Formula 2 below, but is not limited thereto.

[Formula 1]

In Formula 1, R ¹ is -CH ₂ CH ₂ O(C=O)CHCH ₂ , -CH ₂ CH ₂ CH ₂ O(C=O)CHCH ₂ , -CH ₂ CH ₂ CH ₂ CH ₂ O(C =O)CHCH ₂ , is -CH ₂ CH ₂ CH ₂ O(C=O)CHCH ₂ CH ₃ , -CH ₂ CH ₂ CH ₂ CH ₂ O(C=O)CHCH ₂ CH ₃ and X is a halogen element , and n is 0 to 2.

[Formula 2]

X in Formula 2 is -C(=O)O- or -OC(=O)-, and each of R ¹ to R ⁶ may independently be a hydrogen atom, a halogen atom, an alkoxycarbonyl group, a cyano group, or a nitro group.

The liquid crystal resin used to form the r-AQWP film liquid crystal layer is a polymerizable monomer, a polymerization initiator, a tilt control agent, and a leveling agent in addition to the polymerizable liquid crystal compound within a range that does not significantly affect the optical properties of the r-AQWP. agent, a liquid crystal aligning agent, an infrared ray absorbing dye, and/or a solvent may be further included. In addition to this, the liquid crystal resin may further include other additives such as a thixolytic agent, a gelling agent, an antioxidant, and an ultraviolet absorber.

<Chiral dopant>

The chiral dopant serves to induce spiral twist or enhance spiral twist when the liquid crystal compound in the liquid crystal layer is in a liquid crystal state, and a known chiral dopant used in the art may be used, preferably. may use a chiral compound polymerizable with the liquid crystal compound, a photosensitive chiral compound, or the like.

As an example of the polymerizable chiral compound, chiral compounds known in US Patent Publication No. US2003-0026922 and US Patent Registration No. US6217792 may be used. Preferably, a compound represented by Formula 3 below may be used. there is.

[Formula 3]

또는

이며, 바람직하게는

또는

이다. 그리고, 화학식 3의 n은 1 ~ 4이고, 바람직하게는 n은 2 ~ 3이다. 또한, 화학식 3의 B는 C₂~C₈의 직쇄형 알킬렌기, 바람직하게는 C₃~C₅의 직쇄형 알킬렌기이다.A in Formula 3 is -OC(=O)-, -C(=S)-O-,

or

is, preferably

or

am. In Formula 3, n is 1 to 4, preferably n is 2 to 3. Also, B in Formula 3 is a C ₂ -C ₈ straight-chain alkylene group, preferably a C ₃ -C ₅ straight-chain alkylene group.

A specific example of the polymerizable chiral compound is paliocolor LC 759 from BASF, which is commercially available.

In addition, the photosensitive chiral compound has a property of changing its helical twisting power depending on the wavelength and intensity of light it absorbs, and has a molecular structure with one or more chiral centers. , those having the property of forming photoisomers through a photoisomerization reaction by irradiation with light can be used. For a preferred example, a 2-benzylidene-p-menthanone-based compound may be used, and preferably a compound represented by Formula 4 below may be used.

[Formula 4]

In Formula 4, R ¹ is a C ₁ to C ₅ straight-chain alkyl group, C ₃ to C ₅ branched alkyl group, -COOH, -NH ₂ or C ₁ to C ₅ alkoxy group, and R ² is -CN, - NO ₂ , a phenyl group or an alkoxyphenyl group.

As a liquid crystal resin composition, when using a chiral compound, its amount is 0.20 to 1.60 parts by weight, preferably 0.30 to 1.35 parts by weight, preferably 0.50 to 1.32 parts by weight, based on 100 parts by weight of the polymerizable liquid crystal compound of the liquid crystal resin. It is good. At this time, if the chiral compound is used in an amount of less than 0.20 parts by weight or more than 1.60 parts by weight, distortion of the liquid crystal in the liquid crystal layer may be insufficient or excessive, and thus a desired twist angle may not be formed. Therefore, it is preferable to use the chiral compound within the above range.

<Polymeric monomer>

The polymerizable monomer is an optional monomer capable of copolymerizing with a polymerizable liquid crystal compound as an additive component for adjusting the wavelength dispersion characteristics of the retardation film and increasing the high-temperature and moist heat durability through improved dispersibility, and 4-(2-methacryloyl oxyethyloxy)benzoic acid-4'-methoxyphenyl, 4-(6-methacryloyloxyhexyloxy)benzoic acid biphenyl, 4-(2-acryloyloxyethyloxy)benzoic acid-4'-cyano Biphenyl, 4-(2-methacryloyloxyethyloxy)benzoic acid-4'-cyanobiphenyl, 4-(2-methacryloyloxyethyloxy)benzoic acid-3',4'-difluoro Phenyl, 4-(2-methacryloyloxyethyloxy)benzoate naphthyl, 4-acryloyloxy-4'-decylbiphenyl, 4-acryloyloxy-4'-cyanobiphenyl, 4- (2-acryloyloxyethyloxy)-4'-cyanobiphenyl, 4-(2-methacryloyloxyethyloxy)-4'-methoxybiphenyl, 4-(2-methacryloyl Oxyethyloxy)-4'-(4"-fluorobenzyloxy)-biphenyl, 4-acryloyloxy-4'-propylcyclohexylphenyl, 4-methacryloyl-4'-butylbicyclohexyl , 4-acryloyl-4'-amyltolan, 4-acryloyl-4'-(3,4-difluorophenyl)bicyclohexyl, 4-(2-acryloyloxyethyl)benzoic acid (4 -amylphenyl) and 4-(2-acryloyloxyethyl)benzoic acid (4-(4'-propylcyclohexyl)phenyl).

As the composition of the liquid crystal resin, the amount of the polymerizable monomer used is 0.50 to 10.00 parts by weight, preferably 1.00 to 8.00 parts by weight, preferably 3.0 to 7.0 parts by weight, based on 100 parts by weight of the polymerizable liquid crystal compound of the liquid crystal resin. It is good.

<Polymerization Initiator>

The polymerization initiator is a radical polymerization initiator, and a thermal radical initiator and/or an optical radical initiator may be used, preferably an optical radical initiator. Photo-radical initiators include acetophenone-based compounds, biimidazole-based compounds, triazine-based compounds, O-acyloxime-based compounds, onium salt-based compounds, benzoin-based compounds, benzophenone-based compounds, α-diketone-based compounds, and polynuclear quinones. At least one selected from paddy-based compounds, diazo-based compounds, and imidosulfonate-based compounds may be used.

The acetophenone-based compound is 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1- one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-1,2- It may include at least one selected from diphenylethane-1-one, 1,2-octanedione, and 2-benzyl-2-dimethylamino-4'-morpholinobutyrophenone.

The biimidazole-based compound is 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbonylphenyl)-1,2'- Biimidazole, 2,2'-bis(2-bromophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbonylphenyl)-1,2'-biimidazole, 2 ,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4-dichlorophenyl)- 4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4,6-trichlorophenyl)-4,4',5,5'- Tetraphenyl-1,2'-biimidazole, 2,2'-bis(2-bromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2, 2'-bis(2,4-dibromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole and 2,2'-bis(2,4,6-tribe lomophenyl) -4,4', 5,5'-tetraphenyl-1,2'-biimidazole.

As an optical radical initiator, commercially available BASF's Irgacure907, Irgacure 184, Irgacure 369, Irgacure 651, Irgacure 819, Irgacure907, Irgacure OXE02, etc. may be used, or Adekaoptomer N1919 from ADEKA may be used.

As the composition of the liquid crystal resin, the amount of the polymerization initiator is 0.05 to 4.00 parts by weight, preferably 0.1 to 2.0 parts by weight, preferably 0.2 to 1.0 parts by weight, based on 100 parts by weight of the polymerizable liquid crystal compound of the liquid crystal resin. good night.

<Leveling agent>

The leveling agent serves to improve the leveling property of the surface of the retardation film while improving the dispersibility of the liquid crystal compound in the liquid crystal layer, and a fluorine-based surfactant and/or a silicone-based surfactant may be used. In addition, as the fluorine-based surfactant, a pentaerythritol-based surfactant or a dipentaerythritol-based surfactant may be used. As an example of the pentaerythritol-based surfactant, there is a compound represented by Formula 5 below, but the present invention is not limited thereto.

[Formula 5]

이다.In Formula 5, R ¹ is a methylene group, an ethylene group, or a propylene group, and each of R ² to R ⁴ is independently -C _n F _2n+1 , -C _n F _2n H, -CF ₂ O(C ₂ F ₄ )OCF ₃ , or

am.

As a liquid crystal resin composition, when using a leveling agent, its amount is 0.5 to 10.00 parts by weight, preferably 0.8 to 7.5 parts by weight, preferably 1.0 to 5.0 parts by weight, based on 100 parts by weight of the polymerizable liquid crystal compound of the liquid crystal resin. good night.

<liquid crystal aligning agent>

The liquid crystal alignment agent is a polymer having an optical alignment group, and the optical alignment group may include an azobenzene-containing group, a cinnamic acid structure-containing group, a chalcone-containing group, a benzophenone-containing group, and/or a coumarin-containing group. In addition, the polymer may include at least one polymer selected from polyorganosiloxane, styrene-maleimide-based copolymer, acrylic polymer, polyamic acid, polyimide, and polyamic acid ester.

As the composition of the liquid crystal resin, when using the liquid crystal aligning agent, its amount is 2.00 to 10.00 parts by weight, preferably 2.00 to 7.00 parts by weight, preferably 2.0 to 5.0 parts by weight, based on 100 parts by weight of the polymerizable liquid crystal compound of the liquid crystal resin. It is good.

<Infrared ray absorbing dye>

As the infrared absorbing dye, any dye absorbing light with a wavelength of 680 to 900 m may be used without particular limitation. Preferably, the infrared absorbing dye is a dichroic dye having different absorbances in the direction of the major axis of the molecule and the absorbance in the direction of the minor axis of the molecule. Examples of such infrared absorbing pigments include diketopyrrolopyrrole pigments, diimmonium pigments, phthalocyanine pigments, naphthalocyanine pigments, azo pigments, polymethane pigments, anthraquinone pigments, There are pyrylium-based pigments, squarylium-based pigments, triphenylmethane-based pigments, cyanine-based pigments, and aminium-based pigments.

As the composition of the liquid crystal resin, when using the infrared absorbing dye, its amount is 1.00 to 15.00 parts by weight, preferably 1.50 to 10.00 parts by weight, preferably 2.0 to 5.0 parts by weight, based on 100 parts by weight of the polymerizable liquid crystal compound of the liquid crystal resin. It is good.

<Tilt control agent>

The tilt control agent serves to control the tilt angle by reducing or increasing the tilt angle of the liquid crystalline compound, and may include at least one selected from a compound represented by Formula 6 and a polymer represented by Formula 7 there is.

[Formula 6]

R ¹ and R ² in Formula 6 are independently a hydrogen atom, -(OCH ₂ ) _n C ₆ F ₁₃ , -(OCH ₂ CH ₂ ) _n C ₆ F ₁₃ , -(OCH ₂ CH ₂ CH ₂ ) _n C ₆ F ₁₃ or -(OCH ₂ CH ₂ CH ₂ CH ₂ ) _n C ₆ F ₁₃ , where n is an integer from 1 to 3.

[Formula 7]

R ¹ and R ⁸ in Formula 7 are independently a hydrogen atom, -OH, -COOH or -SO ₃ H, and R ² , R ⁴ and R ⁶ are independently a hydrogen atom, a C ₁ ~ C ₃ alkyl group or -COOH And, R ³ , R ⁵ and R ⁷ are independently -COOH, -COOCH ₂ (CF ₂ ) _n H, -COOCH ₂ CH ₂ (CF ₂ ) _n H or -COOCH ₂ CH ₂ OH, and n is 3 to is an integer of 10, x is an integer of 40 to 100, y is an integer of 10 to 30, and z is an integer of 2 to 10.

As a composition of the liquid crystal resin, when using the tilt control agent, its amount is 0.001 to 2.00 parts by weight, preferably 0.01 to 1.80 parts by weight, preferably 0.1 to 1.5 parts by weight, based on 100 parts by weight of the polymerizable liquid crystal compound of the liquid crystal resin. It is good.

<Solvent>

The solvent is propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, ethylene glycol monobutyl ether, diethylene glycol ethyl methyl ether, tetrahydrofuran, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl acetate, acetate n -Butyl, isobutyl acetate, t-butyl acetate, ethyl acetoacetate, propylene glycol monomethyl ether acetate, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, 1 , 2-dimethyl-2-imidazolidinone and N,N-dimethylformamide may contain one or two or more selected from among. In addition, the amount of solvent used is 50 to 150 parts by weight, preferably 50 to 120 parts by weight, more preferably 80 to 120 parts by weight, based on 100 parts by weight of the polymerizable liquid crystal compound. At this time, if the solvent amount is less than 50 parts by weight, the viscosity of the liquid crystal resin is too high and the coating workability is too poor, and using 150 parts by weight of the liquid crystal resin is too low to adversely affect the liquid crystal orientation. It is good.

<Optical Alignment Film (Optical Alignment Layer)>

The photo-alignment layer (photo-alignment layer) may be prepared by coating, drying, and rubbing a liquid crystal photo-alignment agent (or a resin for an alignment layer) on a support.

The application is a coating commonly known in the art such as curtain coating, extrusion coating, roll coating, spin coating, dip coating, bar coating, spray coating, slide coating, print coating, gravure coating, die coating, cap coating or dip coating. The coating may be performed by a method, and a liquid crystal photo-alignment layer having a form of a thin film, film, sheet, or the like may be manufactured.

In addition, an optical film such as a retardation film may be manufactured by directly coating the liquid crystal optical alignment agent on one surface of a liquid crystal film to form a thin film, or by combining the liquid crystal optical alignment agent with a liquid crystal film after forming a film or sheet.

In addition, the liquid crystal photo-alignment agent may include a photo-alignment compound including at least one selected from polyimide, polyvinyl alcohol, polyester, polyallylate, polyamideimide, and polyetherimide. Preferably, the following A polymer containing a repeating unit represented by Formula 1; and a copolymer comprising a repeating unit represented by Formula 1 and a repeating unit represented by Formula 2 below; It may include one or more selected from among.

In addition, the photo-alignment compound is prepared by preparing a compound represented by the following Chemical Formula 3 and a compound represented by the following Chemical Formula 4, respectively; And a compound including at least one selected from a compound represented by the following Chemical Formula 3 and a compound represented by the following Chemical Formula 4 is subjected to a polymerization reaction to form a polymer comprising a repeating unit represented by the following Chemical Formula 1, or the following Chemical Formula 1 and It can be prepared by performing a process including; two steps of preparing a copolymer including a repeating unit represented by Formula 2.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

In Formula 1 and/or Formula 3, R ¹ is a hydrogen atom or a C ₁ to C ₃ alkyl group, preferably R ¹ is a C ₁ to C ₃ alkyl group, and more preferably R ¹ is a C ₁ to C 3 alkyl group. It is an alkyl group of C ₂ .

In addition, A in Formula 1 and/or Formula 3 is -OR ³ -, -NHR ³ - or -SR ³ -, preferably -OR ³ - or -SR ³ -, more preferably -OR ³ -am. ƒZ, and R ³ is a C ₂ to C ₅ straight-chain alkylene group, preferably a C ₂ to C ₅ straight-chain alkylene group, more preferably an ethylene group.

또는

이다. 또한, 상기 R⁴는 C₁~C₁₀의 직쇄형 알킬기, C₃~C₁₀의 분쇄형 알킬기, 탄소원자 1개 이상이 헤테로 원자로 치환된 C₂~C₁₀의 직쇄형 헤테로 알킬기 또는 탄소원자 1개 이상이 헤테로 원자로 치환된 C₃~C₁₀의 분쇄형 헤테로 알킬기이고, 바람직하게는 R⁴는 C₁~C₅의 직쇄형 알킬기, C₄~C₁₀의 분쇄형 알킬기, 탄소원자 1개 이상이 헤테로 원자로 치환된 C₂~C₅의 직쇄형 헤테로 알킬기 또는 탄소원자 1개 이상이 헤테로 원자로 치환된 C₄~C₁₀의 분쇄형 헤테로 알킬기이며, 더욱 바람직하게는 R⁴는 C₁~C₅의 직쇄형 알킬기 또는 C₄~C₁₀의 분쇄형 알킬기이다.In addition, the R ² of Formula 1 and/or Formula 3 is

or

am. In addition, R ⁴ is a C ₁ ~ C ₁₀ straight-chain alkyl group, a C ₃ ~ C ₁₀ branched alkyl group, a C ₂ ~ C ₁₀ straight-chain heteroalkyl group in which at least one carbon atom is substituted with a hetero atom, or a carbon atom 1 It is a C ₃ ~ C ₁₀ branched heteroalkyl group substituted with at least one hetero atom, preferably R ⁴ is a C ₁ ~ C ₅ straight chain alkyl group, a C ₄ ~ C ₁₀ branched alkyl group, or at least 1 carbon atom. A C ₂ ~ C ₅ straight-chain heteroalkyl group substituted with a hetero atom or a C ₄ ~ C ₁₀ branched hetero alkyl group in which at least one carbon atom is substituted with a hetero atom, more preferably R ⁴ is C ₁ ~ C ₅ A straight chain alkyl group or a C ₄ ~ C ₁₀ branched alkyl group.

In Formula 1 and/or Formula 3, n is an integer of 0 to 20, preferably an integer of 0 to 10, more preferably n is an integer of 0 to 5.

In addition, m in Formula 1 is an integer satisfying a weight average molecular weight of 1,000 to 1,000,000 g/mol of the polymer, preferably an integer satisfying a weight average molecular weight of 5,000 to 500,000 g/mol of the polymer, more preferably a polymer. It is an integer that satisfies the weight average molecular weight of 50,000 to 250,000 g/mol.

In Formula 1, * means a binding site of a repeating unit in a polymer.

And, R ¹ in Formula 2 and/or Formula 4 is a C ₁ ~ C ₃ alkyl group, preferably R ¹ is a C ₁ ~ C ₃ alkyl group, more preferably R ¹ is a C ₁ ~ C ₂ is an alkyl group.

In addition, R ⁵ in Formula 2 and/or Formula 4 is a C ₁ ~ C ₅ straight-chain alkyl group, a C ₄ ~ C ₁₀ branched alkyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted phenoxy group, or a substituted or It is an unsubstituted N-phenylamino group, preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted phenoxy group, or a substituted or unsubstituted N-phenylamino group.

In Formula 2, L is an integer of 1 to 20, preferably L is an integer of 1 to 10, more preferably L is an integer of 1 to 8.

Preferred examples of polymers including repeating units represented by the photo-alignment compound of the present invention are represented by Chemical Formulas 1-1 to 1-28 in Tables 1 to 3 below.

chemical formula 1-1 1-2 1-3 1-4 R ¹ -CH ₃ -CH ₃ -CH ₃ -CH ₃ A - -OR ³ - -OR ³ - -OR ³ - ^R3 - -CH ₂ CH ₂ - -CH ₂ CH ₂ - -CH ₂ CH ₂ - ^R2

^R4 -CH ₃ m 4 to 3448 3 to 2994 3 to 2645 3 to 2369 n 0 One 2 3 chemical formula 1-5 1-6 1-7 1-8 R ¹ -CH ₃ -CH ₃ -CH ₃ -CH ₃ A - -OR ³ - -OR ³ - -OR ³ - ^R3 - -CH ₂ CH ₂ - -CH ₂ CH ₂ - -CH ₂ CH ₂ - ^R2

^R4 -CH ₂ CH ₂ CH(CH ₃ ) ₂ m 3 to 2890 3 to 2564 3 to 2304 3 to 2092 n 0 One 2 3 chemical formula 1-9 1-10 1-11 1-12 R ¹ -CH ₃ -CH ₃ -CH ₃ -CH ₃ A - -OR ³ - -OR ³ - -OR ³ - ^R3 - -CH ₂ CH ₂ - -CH ₂ CH ₂ - -CH ₂ CH ₂ - ^R2

^R4 -CH ₂ CH(CH ₂ CH ₃ )CH ₂ CH ₂ CH ₂ CH ₃ m 3 to 2958 3 to 2314 3 to 2100 2 ~1923 n 0 One 2 3

chemical formula 1-13 1-14 1-15 1-16 R ¹ -CH ₃ -CH ₃ -CH ₃ -CH ₃ A - -OR ³ - -OR ³ - -OR ³ - ^R3 - -CH ₂ CH ₂ - -CH ₂ CH ₂ - -CH ₂ CH ₂ - ^R2

^R4 -CH ₃ m 4 to 3448 3 to 2994 3 to 2645 3 to 2369 n 0 One 2 3 chemical formula 1-17 1-18 1-19 1-20 R ¹ -CH ₃ -CH ₃ -CH ₃ -CH ₃ A - -OR ³ - -OR ³ - -OR ³ - ^R3 - -CH ₂ CH ₂ - -CH ₂ CH ₂ - -CH ₂ CH ₂ - ^R2

^R4 -CH ₂ CH ₂ CH(CH ₃ ) ₂ m 3 to 2890 3 to 2564 3 to 2304 3 to 2092 n 0 One 2 3 chemical formula 1-21 1-22 1-23 1-24 R ¹ -CH ₃ -CH ₃ -CH ₃ -CH ₃ A - -OR ³ - -OR ³ - -OR ³ - ^R3 - -CH ₂ CH ₂ - -CH ₂ CH ₂ - -CH ₂ CH ₂ - ^R2

^R4 -CH ₂ CH(CH ₂ CH ₃ )CH ₂ CH ₂ CH ₂ CH ₃ m 3 to 2958 3 to 2314 3 to 2100 2 ~1923 n 0 One 2 3

chemical formula 1-25 1-26 1-27 1-28 R ¹ -CH ₃ -CH ₃ -CH ₃ -CH ₃ A -SR ³ - -SR ³ - -NHR ³ - -NHR ³ - ^R3 -CH ₂ CH ₂ - -CH ₂ CH ₂ - -CH ₂ CH ₂ - -CH ₂ CH ₂ - ^R2

^R4 -CH ₃ m 3 to 2857 3 to 2439 4 to 3003 3 to 2659 n One 2 One 2

The photo-alignment compound of the present invention described above can be used as an photo-alignment agent for photo-alignment of liquid crystals of a liquid crystal film, and can be used as an alignment agent composition or a photosensitive material.

The liquid crystal photo-alignment agent of the present invention includes the photo-alignment compound; And a solvent; may include.

The solvent is a solvent that does not dissolve or affect the substrate of the plastic material, and the solubility of the photo-alignment compound is 10 mg/mL or more, preferably 20 mg/mL or more, more preferably 22 to 110 mg/mL can be used that satisfies At this time, the solubility is a measurement of the maximum amount of solute that can be dissolved in 1 mL of a solvent at room temperature (25° C.).

As specific examples of solvents satisfying such solubility, the solvents include non-polar solvents; and polar solvents; It may include one or more selected from among.

The non-polar solvent may include at least one selected from benzene, toluene, ethyl acetate, butyl acetate, tetrahydrofuran (THF), PGMEA (Propylene glycol methyl ether acetate), dichloromethane, and chloroform, preferably ethyl acetate , Butyl acetate, may include one or more selected from tetrahydrofuran (THF) and PGMEA, more preferably may include one or more selected from butyl acetate, tetrahydrofuran (THF) and PGMEA.

The polar solvent may include at least one selected from cyclopentanone, cyclohexanone, acetone, dimethylformamide (DMF) and acetonitrile, and preferably acetone, dimethylformamide (DMF), acetonitrile and dimethyl It may contain at least one selected from sulfoxide (DMSO).

In addition, two or more of the non-polar solvents and / or polar solvents may be mixed and used in consideration of the type of photo-alignment agent, the characteristics of the support to which the coating liquid is applied, the manufacturing conditions, etc., and a preferred embodiment is toluene and cyclohexane Paddy, toluene and PGMEA, butyl acetate and cyclohexanone, butyl acetate and PGMEA, etc. may be appropriately mixed and used. It can be used by mixing butyl acetate and cyclohexanone in a volume ratio of 4:1, butyl acetate and cyclohexanone in a volume ratio of 1 to 4:1, and butyl acetate and PGMEA in a volume ratio of 1 to 4:1.

And, the thickness of the alignment layer may be 0.001 ~ 2.00 μm, preferably 0.001 ~ 1.00 μm.

In addition, a known support may be used as the support, and it is preferable to use a material made of a material that can be separated from the alignment film after formation of the alignment film. For example, the support may be a polyolefin resin such as polyethylene, polypropylene, norbornene-based polymer; Cyclic olefin resin; polyvinyl alcohol resin; polyethylene terephthalate resin; polymethacrylic acid ester resin; polyacrylic acid ester resin; cellulose ester resins such as triacetyl cellulose resin, diacetyl cellulose resin, and cellulose acetate propionate; polyethylene naphthalate; polycarbonate resin; polysulfone resin; polyethersulfone resin; polyether ketone resin; polyphenylene sulfide resin; and polyphenylene oxide resin; One made of a resin containing at least one selected from among may be used.

In addition, the surface of the support may be subjected to release treatment such as silicon treatment.

<HWP film>

As described above, the retardation film of the present invention may further include an HWP film.

The HWP film may be introduced by forming on top of the r-AQWP film so as to exist between the polarizer and the r-AQWP.

Further, the HWP film may use a stretched film or may use a liquid crystal polymer film including a liquid crystal layer formed of a liquid crystal resin containing a polymerizable liquid crystal compound and an alignment layer for liquid crystal alignment. In addition, the alignment may be performed through rubbing alignment or optical alignment.

<C plate layer>

The C plate layer used in the present invention is a liquid crystal polymer film, or may be formed by coating a liquid crystal polymer on a retardation film or polarizer.

And, when the C plate layer is a liquid crystal polymer film, it may be a stretched film or a film in which a liquid crystal layer made of liquid crystal polymer and an alignment film layer for aligning liquid crystals are laminated. In addition, the alignment may be performed through rubbing alignment or optical alignment.

The liquid crystal polymer film constituting the C plate layer may be a vertically aligned liquid crystal polymer film that satisfies the refractive index of Equation 6.

[Equation 6]

n _z > n _x ≒ n _y

In Equation 6, n _x is the refractive index in the direction in which the refractive index in the plane in the slow axis direction is the maximum, n _y is the refractive index in the direction orthogonal to the slow axis in the plane and in the plane, and n _z means the refractive index in the thickness direction .

In addition, the C plate layer may have a thickness direction retardation (R _th ) of -120 to -30 nm, preferably -90 to -60 nm according to Equation 1 below, and a circularly polarized film to which the C plate layer is applied (anti-reflection Film) can be adjusted and applied according to a large TV display, mobile display, rollable display, etc. to be applied.

[Equation 1]

_Rth = {(n _x +n _y )/2 - n _z }×d

In Equation 1, n _x is the refractive index in the direction in which the refractive index in the plane in the slow axis direction is the maximum, n _y is the refractive index in the direction orthogonal to the slow axis in the plane and in the plane, n _z is the refractive index in the thickness direction, d is is the thickness of the film.

Hereinafter, the present invention will be described in more detail through examples, but the following examples are not intended to limit the scope of the present invention, which should be interpreted to aid understanding of the present invention.

[Example]

Preparation Example 1: Preparation of photo-alignment compound

A polymer having a repeating unit represented by Chemical Formula 1-2 was prepared as follows through the reaction shown in Reaction Scheme 1 below.

[Scheme 1]

(1) Preparation of compound A

40 g (220 mmol) of 4-methoxycinnamic acid, 240 g (2.2 mol) of diethylene glycol, and 68 g (560 mmol) of dimethylaminopyridine (DMAP) were dissolved in 400 mL of acetonitrile, and 1-ethyl 56 g (290 mmol) of -3-(3-dimethylaminopropyl)carbodiimide (EDCI) was added dropwise.

Next, after stirring at 25° C. for 18 hours, acetonitrile was distilled off under reduced pressure and dissolved in 600 mL of ethyl acetate. The solution was washed three times with 200 mL of 1M HCl aqueous solution to remove residual DMAP, and washed three times with 300 mL of saturated NaHCO ₃ aqueous solution to remove a small amount of 4-methoxycinnamic acid.

Next, ethyl acetate was distilled off under reduced pressure to obtain 53 g (200 mmol) of Compound A of Scheme 1.

(2) Preparation of compound B

17 g (65 mmol) of the above compound A, 7.3 g (85 mmol) of methacrylic acid, and 1.6 g (13 mmol) of DMAP were dissolved in 120 mL of dichloromethane, and 24 g (120 mmol) of N in 60 mL of dichloromethane ,N'-dicyclohexylcarbodiimide (DCC) was slowly added dropwise.

Next, after stirring at 25°C for 2 hours, the precipitate was filtered off and dichloromethane was distilled off under reduced pressure.

Next, the residue was purified by silica gel column chromatography (hexane/ethyl acetate = 5/1) to obtain 16 g (48 mmol) of compound B of Scheme 1 as a white powder.

(3) Preparation of a polymer containing a repeating unit represented by Chemical Formula 1-2

After dissolving 11 g (33 mmol) of compound B and 85 mg (0.52 mmol) of 2,2'-azobisisobutyronitrile (AIBN) in 20 mL of DMF, it was flushed with argon for 15 minutes. .

Next, after stirring at 70° C. for 4 hours, the solution was added dropwise to 500 mL of methanol at room temperature. The precipitate precipitated was separated by filtration, dissolved in 20 mL of dichloromethane, and then added dropwise to 500 mL of methanol to precipitate. This process was repeated three times, followed by filtration and drying to prepare an optical alignment compound (white powder, weight average molecular weight of 190,000 g/mol), which is a polymer containing 9.4 g of a repeating unit represented by Chemical Formula 1-2.

Preparation example 2

A polymer having a repeating unit represented by Chemical Formula 1-5 was prepared as follows through a reaction shown in Reaction Scheme 2 below.

[Scheme 2]

(1) Preparation of C compound

40 g (240 mmol) of 4-hydroxycinnamic acid was dissolved in 400 mL of ethanol, and NaOH aqueous solution (20 g, 140 mL) was slowly added dropwise, followed by stirring at 95 ^° C. for 30 minutes.

Next, 46 mL of isoamyl bromide was slowly added dropwise, followed by stirring at 95 ^° C. for additional 3 days. After acidification by adding 5N HCl aqueous solution, the precipitate was separated by filtration. The remaining small amount of impurities was washed away with heptane to give 54 g (230 mmol) of Scheme 2 C compound as a white powder.

(2) Preparation of D compound

30 g (130 mmol) of the white powdery compound A, 22 g (170 mmol) of 2-hydroxyethyl methacrylate, and 1.6 g (13 mmol) of 4-dimethylaminopyridine (DMAP) were mixed with tetrahydrofuran (THF). Dissolved in 200 mL, and 34 g (170 mmol) of N,N'-dicyclohexylcarbodiimide (DCC) in 100 mL of THF was slowly added dropwise.

Next, after stirring at 25°C for 5 hours, the precipitate was removed by filtration and THF was distilled off under reduced pressure.

Next, the residue was purified by silica gel column chromatography (hexane/ethyl acetate = 45/1) to obtain 31 g (89 mmol) of compound B of Scheme 1 as a white powder.

(3) Preparation of a polymer containing a repeating unit represented by Formula 1-5

After dissolving 21 g (61 mmol) of the previously prepared compound B and 160 mg (1.0 mmol) of 2,2'-azobisisobutyronitrile (AIBN) in 42 mL of dimethylformamide (DMF), it was stirred for 15 minutes. It was flushed with argon.

Next, after stirring at 70° C. for 6 hours, the solution was added dropwise to 800 mL of methanol at room temperature (about 25° C.). After separating the precipitate by filtration, it was dissolved in 40 mL of dichloromethane and then added dropwise to 800 mL of methanol to precipitate. This process was repeated three times, followed by filtration and drying to prepare an optical alignment agent (white powder, weight average molecular weight of 83,000 g/mol), which is a polymer containing 19 g of a repeating unit represented by Chemical Formula 1-5.

Preparation Example 3

A polymer having a repeating unit represented by Chemical Formula 1-9 was prepared as follows through the reaction shown in Reaction Scheme 3 below.

[Scheme 3]

(1) Preparation of E compound

60 g (370 mmol) of 4-hydroxycinnamic acid was dissolved in 600 mL of ethanol, and NaOH aqueous solution (30 g, 200 mL) was slowly added dropwise, followed by stirring at 95 ^° C. for 30 minutes.

Next, 105 mL of 2-ethylhexyl bromide was slowly added dropwise, followed by stirring at 95 ^° C. for additional 3 days. After acidification by adding 5N HCl aqueous solution, the precipitate was separated by filtration. The remaining small amount of impurities was washed away with heptane to give 94 g (340 mmol) of E compound of Scheme 3 as a white powder.

(2) Preparation of compound F

50 g (180 mmol) of the above compound E in the form of a white powder, 30 g (230 mmol) of 2-hydroxyethyl methacrylate, and 2.2 g (18 mmol) of 4-dimethylaminopyridine (DMAP) were mixed with tetrahydrofuran (THF). Dissolved in 350 mL, and 47 g (230 mmol) of N,N'-dicyclohexylcarbodiimide (DCC) in 150 mL of THF was slowly added dropwise.

Next, after stirring at 25°C for 5 hours, the precipitate was removed by filtration and THF was distilled off under reduced pressure.

Next, the residue was purified by silica gel column chromatography (hexane/ethyl acetate = 50/1) to obtain 51 g (130 mmol) of compound F of Scheme 3 as a white powder.

(3) Preparation of a polymer containing repeating units represented by Chemical Formulas 1-9

After dissolving 16 g (41 mmol) of compound F prepared above and 100 mg (0.61 mmol) of 2,2'-azobisisobutyronitrile (AIBN) in 30 mL of dimethylformamide (DMF), it was stirred for 15 minutes. It was flushed with argon.

Next, after stirring at 70° C. for 6 hours, the solution was added dropwise to 600 mL of methanol at room temperature (about 25° C.). The precipitate precipitated was separated by filtration, dissolved in 30 mL of dichloromethane, and then added dropwise to 600 mL of methanol to precipitate. This process was repeated three times, followed by filtration and drying to prepare an optical alignment compound (white powder, weight average molecular weight of 95,000 g/mol), which is a polymer containing 14 g of repeating units represented by Chemical Formulas 1-9.

Preparation Example 4

A polymer having a repeating unit represented by Chemical Formula 1-15 was prepared as follows through a reaction shown in Scheme 4 below.

[Scheme 4]

(1) Preparation of G compound

60 g (340 mmol) of methyl 4-hydroxycinnamate was dissolved in 100 mL of dimethylformamide (DMF), and 190 g (1.4 mol) of K ₂ CO ₃ and 28 g (170 mmol) of KI were added dropwise, followed by 80 ^o C for 10 min.

Next, 100 g (610 mmol) of triethylene glycol monochlorohydrin was slowly added dropwise, followed by stirring at 80 ^° C. for additional 24 hours.

Next, the salts were removed by filtration and concentrated under reduced pressure, and then the solution was added dropwise to 900 mL of distilled water at room temperature. The precipitate precipitated was washed with distilled water to obtain 91 g (290 mmol) of Compound G of Scheme 4.

(2) Preparation of H compound

35 g (110 mmol) of the above compound G, 13 g (150 mmol) of methacrylic acid, and 2.8 g (23 mmol) of 4-dimethylaminopyridine (DMAP) were dissolved in 200 mL of dichloromethane, and 41 g in 120 mL of dichloromethane. g (200 mmol) of N,N'-dicyclohexylcarbodiimide (DCC) was slowly added dropwise.

Next, after stirring at 25°C for 4 hours, the precipitate was filtered off and dichloromethane was distilled off under reduced pressure.

Next, the residue was purified by silica gel column chromatography (hexane/ethyl acetate = 10/1) to obtain 33 g (87 mmol) of Compound H of Scheme 4.

(3) Preparation of a polymer containing a repeating unit represented by Formula 1-15

After dissolving 35 g (92 mmol) of the previously prepared H compound and 230 mg (1.4 mmol) of 2,2'-azobisisobutyronitrile (AIBN) in 70 mL of DMF, flushing with argon for 15 minutes ( fluxing).

Next, after stirring at 70° C. for 4 hours, the solution was added dropwise to 1.2 L of methanol at room temperature. The precipitate precipitated was separated by filtration, dissolved in 60 mL of dichloromethane, and then added dropwise to 1.2 L of methanol to precipitate. This process was repeated three times, followed by filtration and drying to prepare an optical alignment compound (white powder, weight average molecular weight of 110,000 g/mol), which is a polymer containing 30 g of repeating units represented by Chemical Formulas 1-15.

Preparation Example 5

A polymer having a repeating unit represented by Chemical Formula 1-23 was prepared as follows through a reaction shown in Scheme 5 below.

[Scheme 5]

(1) Preparation of compound I

45 g (160 mmol) of 2-ethylhexyl-4-hydroxycinnamate was dissolved in 80 mL of dimethylformamide (DMF), and 95 g (690 mmol) of K ₂ CO ₃ and 15 g (90 mmol) of KI were added dropwise. After that, the mixture was stirred at 80 ^° C for 20 minutes.

Next, 54 g (320 mmol) of triethylene glycol monochlorohydrin was slowly added dropwise, followed by stirring at 80 ^° C. for additional 24 hours.

Next, the salts were removed by filtration and concentrated under reduced pressure, and the solution was added dropwise to 750 mL of distilled water at room temperature. The precipitate precipitated was washed with distilled water to obtain 53 g (130 mmol) of Compound I of Scheme 5.

(2) Preparation of J compound

25 g (61 mmol) of the above compound I, 6.8 g (80 mmol) of methacrylic acid, and 1.5 g (12 mmol) of 4-dimethylaminopyridine (DMAP) were dissolved in 150 mL of dichloromethane, and 23 g in 60 mL of dichloromethane. g (110 mmol) of N,N'-dicyclohexylcarbodiimide (DCC) was slowly added dropwise.

Next, after stirring at 25°C for 4 hours, the precipitate was filtered off and dichloromethane was distilled off under reduced pressure.

Next, the residue was purified by silica gel column chromatography (hexane/ethyl acetate = 15/1) to obtain 20 g (42 mmol) of Compound J of Scheme 5.

(3) Preparation of a polymer containing a repeating unit represented by Chemical Formula 1-23

After dissolving 18 g (38 mmol) of the previously prepared J compound and 94 mg (0.57 mmol) of 2,2'-azobisisobutyronitrile (AIBN) in 40 mL of DMF, flushing with argon for 15 minutes. ) was done.

Next, after stirring at 70° C. for 4 hours, the solution was added dropwise to 800 mL of methanol at room temperature. After separating the precipitate by filtration, it was dissolved in 40 mL of dichloromethane and then added dropwise to 800 mL of methanol to precipitate. This process was repeated three times, followed by filtration and drying to prepare an optical alignment compound (white powder, weight average molecular weight: 75,000 g/mol), which is a polymer containing 16 g (33 mmol) of a repeating unit represented by Chemical Formula 1-23.

Experimental Example 1: Measurement of solubility of photo-alignment compound in solvent

The solubility (mg/mL) of the optical alignment compound prepared in Preparation Examples 1 to 5 in the solvent was measured, and the results are shown in Table 4 below.

The measurement of solubility in the solvent is the measurement of the maximum amount (mg) of the solute (photoalignment compound) that can be dissolved in 1 mL of the solvent at 25°C.

division
(Solubility mg/ml, 25℃) Preparation Example 1 Preparation example 2 Preparation Example 3 Preparation Example 4 Preparation Example 5 non-polar
menstruum benzene 86 >100 >100 >100 >100 toluene 92 >100 >100 >100 >100 ethyl acetate 67 82 91 84 94 butyl acetate 24 36 30 46 42 tetrahydrofuran >100 75 88 96 95 PGMEA 45 32 25 40 36 dichloromethane 74 87 80 >100 >100 chloroform >100 92 >100 85 >100 polarity
menstruum cyclo
pentanone 39 42 56 60 44 cyclo
Hexanon 35 45 62 52 56 acetone >100 >100 >100 >100 >100 DMF >100 >100 >100 >100 >100 DMSO 6.4 5.3 2.8 4.3 3.2

Referring to Table 4, all of the compounds of Preparation Examples 1 to 5 in DMSO showed too low solubility.

In addition, butyl acetate and PGMEA (Propylene glycol methyl ether acetate) among non-polar solvents, and cyclopentanone and cyclohexanone among polar solvents showed slightly lower solubility compared to other solvents, but all of them were commercially available at 20 mg/mL or higher. It was confirmed that it had excellent solubility above the acceptable solubility.

Experimental Example 2: Measurement of solubility of photo-alignment compound in solvent

After preparing a mixed solvent by mixing a solvent with slightly low solubility with a solvent with high solubility, the solubility of the photo-alignment compound was measured in the same manner as in Experimental Example 1, and the results are shown in Table 5 below.

Mixed solvent 1 is toluene and cyclohexanone in a 3: 1 volume ratio, mixed solvent 2 is toluene and PGMEA in a 3: 1 volume ratio, mixed solvent 3 is toluene and PGMEA in a 3: 1 volume ratio, mixed solvent 4 is butyl acetate and It is a solvent mixed with PGMEA in a volume ratio of 3:1.

division
(Solubility mg/ml, 25℃) Preparation Example 1 Preparation example 2 Preparation Example 3 Preparation Example 4 Preparation Example 5 Mixed solvent 1 (toluene:cyclohexanone = 3:1) 64 80 52 72 85 Mixed solvent 2 (toluene:PGMEA=3:1) 60 74 54 64 85 Mixed solvent 3 (butyl acetate: cyclohexanone
=3:1) 32 40 36 38 43 Mixed solvent 4 (butyl acetate: PGMEA=3:1) 26 35 29 35 36

Comparing the solubility measurement results of Table 5 with Table 1, it was confirmed that the solubility of the photo-alignment compound generally increased due to the mixed use rather than butyl acetate or PGMEA alone.

Through Experimental Examples 1 and 2, when preparing the liquid crystal photo-alignment layer, a liquid crystal photo-alignment layer was prepared by applying an appropriate solvent in consideration of the type of optical alignment agent used in the liquid crystal photo-alignment layer coating solution, the characteristics of the support to which the coating solution is applied, manufacturing conditions, etc. I was able to confirm that it could be done.

Example 1: Preparation of retardation film (r-AQWP film)

(1) Manufacture of liquid crystal photo-alignment layer

3% by weight of the optical alignment compound of Preparation Example 1 and 93% by weight of the mixed solvent were mixed and stirred to prepare a coating solution for a liquid crystal optical alignment layer. The mixed solvent was prepared by mixing toluene and PGMEA at a volume ratio of 3:1.

Next, the coating liquid for the liquid crystal optical alignment layer was coated on a triacetyl-cellulose (TAC) film substrate having a thickness of 60 μm using a spin coater, and then dried at 90° C. for 2 minutes to prepare a liquid crystal optical alignment layer having a thickness of about 0.3 μm.

(2) Manufacture of liquid crystal resin

2-(C ₁ alkyl)-1,4-phenylenebis(4-(((4-(acryloyloxy)(C ₄ alkoxy)carbonyl)oxy)benzoate and benzo[b]naphtho A reverse wavelength liquid crystal compound containing [2',3':5,6]dioxino[2,3-i]oxantrene disulfonic acid in a weight ratio of 1:0.5 was prepared. It satisfies the refractive index (Δn ₁ ) of -1.

Then, a positive-wavelength liquid crystal compound represented by Chemical Formula 1-1 was prepared. The constant wavelength liquid crystal compound satisfies the refractive index (Δn ₂ ) of Equation 4-1 below.

[Formula 1-1]

In Formula 1-1, R ¹ is -CH ₂ CH ₂ CH ₂ CH ₂ O(C=O)CHCH ₂ , and n is 0.

[Equation 3-1]

0.042 ≤ │Δn│ ≤ 0.048

[Equation 4-1]

0.125 ≤ │Δn ₂ │ ≤ 0.135

Next, a polymerizable liquid crystal compound was prepared so that the reverse wavelength liquid crystal compound and the forward wavelength liquid crystal compound were mixed in a weight ratio of 1:0.2.

Based on 100 parts by weight of the polymerizable liquid crystal compound, 1.1 parts by weight of a polymerizable chiral dopant (paliocolor LC 759 from BASF), a polymerizable monomer, 4-(2-methacryloyloxyethyloxy)-4'-( 3.8 parts by weight of 4″-fluorobenzyloxy)-biphenyl, 0.32 parts by weight of Irgacure 907 (BASF) as an optical radical initiator, 4.0 parts by weight as a leveling agent, 2.2 parts by weight of a polyamic acid ester polymer having a coumarin-containing group as a liquid crystal alignment agent A liquid crystal resin was prepared by mixing 0.64 parts by weight of a tilt control agent, a compound represented by Formula 6-1, and 87 parts by weight of a mixed solvent in which propylene glycol monomethyl ether and N-methyl-2-pyrrolidone were mixed as solvents.

[Formula 6-1]

R ¹ and R ² in Formula 6-1 are -(OCH ₂ CH ₂ CH ₂ ) _n C ₆ F ₁₃ , and n is 2.

[Formula 5-1]

In Formula 5-1, R ¹ is a methylene group, and each of R ² , R ³ , and R ⁴ is -CF ₂ O(C ₂ F ₄ )OCF ₃ .

(2) film formation

An alignment film in which an alignment film layer having a thickness of 0.3 µm was formed on an upper portion of a cellulose ester support (substrate) having a thickness of 60 µm was prepared.

After bar-coating and applying the previously prepared liquid crystal resin to the alignment layer, drying at about 120° C. for 60 seconds, UV irradiation (wavelength: 365 nm, light intensity: 500 mJ/cm ² ) with a high-pressure mercury lamp under a nitrogen atmosphere, and curing. By forming a liquid crystal layer, an r-AQWP film (retardation film) was prepared.

In the retardation film, the total thickness of the alignment layer and the liquid crystal layer excluding the support was 3.10 μm.

Examples 2 to 6

A liquid crystal resin and a retardation film were prepared in the same manner as in Example 1, but as shown in Table 1 below, the liquid crystal resin was prepared by varying the weight ratio of the reverse wavelength liquid crystal compound and the forward wavelength liquid crystal compound in the liquid crystal resin, and then the retardation film was used. was prepared, and Examples 2 to 5 were carried out, respectively.

Examples 7 to 10

In the same manner as in Example 1, a liquid crystal photo-alignment layer, a liquid crystal resin, and a retardation film were prepared in the same manner as in Example 1, but the liquid crystal photo-alignment layer was prepared by changing the type of optical alignment compound in the liquid crystal photo-alignment agent as shown in Table 6 below. After manufacturing, a retardation film was prepared using this, and Examples 6 to 9 were performed, respectively.

Comparative Example 1

A liquid crystal resin and a retardation film were prepared in the same manner as in Example 1, but as a liquid crystal compound in the liquid crystal resin, only a reverse wavelength liquid crystal compound was used and the liquid crystal resin was prepared without using a chiral dopant, and then the liquid crystal resin A retardation film having a thickness of 3.44 μm was prepared by using.

Comparative Example 2

A liquid crystal resin and a retardation film were prepared in the same manner as in Example 1, but as shown in Table 1 below, the liquid crystal resin was prepared by varying the weight ratio of the reverse wavelength liquid crystal compound and the forward wavelength liquid crystal compound in the liquid crystal resin, and then using this to prepare a 2.12㎛ A thick retardation film was prepared.

Comparative Example 3

A liquid crystal resin and a retardation film were prepared in the same manner as in Example 1, except that 2 parts by weight of a chiral dopant was used, and the liquid crystal resin was prepared in the same manner and composition as in Example 1, and then the retardation was made using the liquid crystal resin. A film was made.

division in liquid crystal resin
Reverse wavelength liquid crystal and forward wavelength liquid crystal compound weight ratio Chiral dopant usage liquid crystal photo-alignment agent
photo-alignment compound Example 1 1:0.25 1.1 parts by weight Preparation Example 1 Example 2 1:0.11 1.1 parts by weight Preparation Example 1 Example 3 1:0.18 1.1 parts by weight Preparation Example 1 Example 4 1:0.43 1.1 parts by weight Preparation Example 1 Example 5 1:0.53 1.1 parts by weight Preparation Example 1 Example 6 1:0.25 1.3 parts by weight Preparation Example 1 Example 7 1:0.18 1.1 parts by weight Preparation example 2 Example 8 1:0.43 1.1 parts by weight Preparation Example 3 Example 9 1:0.53 1.1 parts by weight Preparation Example 4 Example 10 1:0.25 1.1 parts by weight Preparation Example 5 Comparative Example 1 1:0 0 Preparation Example 1 Comparative Example 2 1:0.77 1.1 parts by weight Preparation Example 1 Comparative Example 3 1:0.25 2.0 parts by weight Preparation Example 1

Experimental Example 1: Measurement of optical properties of retardation film

Optical axis retardation and refractive index (Δn = difference between extraordinary light refractive index (n _e ) and normal light refractive index ( _no )) of the retardation films prepared in Examples 1 to 10 and Comparative Examples 1 to 3 were measured, and the results are shown in Table 2 below. The thickness reduction rate in Table 2 below is calculated and shown based on the thickness of the retardation film of Comparative Example 1.

division optical on-axis phase difference index of refraction
(Δn) thickness reduction rate
(thickness) twist angle α β Comparative Example 1 0.841 1.029 0.04 0% (3.44㎛) 10° or less Example 1 0.978 0.991 - 10.47% (3.08㎛) 58-62° Example 2 0.936 1.018 - 4.94% (3.27㎛) 60-64° Example 3 0.955 1.002 - 5.82% (3.24㎛) 59-63° Example 4 0.988 0.989 - 17.73% (2.83㎛) 56-60° Example 5 0.992 0.982 - 23.55% (2.63㎛) 55-59° Example 6 0.977 0.990 - 6.98% (3.20㎛) 66-67° Example 7 0.974 0.995 - 9.88% (3.10㎛) 58-62° Example 8 0.972 0.988 - 16.28% (2.88㎛) 57-61° Example 9 0.971 0.986 - 18.90% (2.79㎛) 56-60° Example 10 0.968 0.984 - 20.93% (2.72㎛) 56-60° Comparative Example 2 1.105 0.921 - 38.37% (2.12㎛) 54-58° Comparative Example 3 0.958 1.004 - 9.88% (3.10㎛) 104-108° α is R ₄₅₀ /R ₅₅₀ , β is R ₆₅₀ /R ₅₅₀ , R ₄₅₀ is the optical axial retardation at a light wavelength of 450 nm, R ₅₅₀ is the optical axial retardation at a light wavelength of 450 nm,
R ₆₅₀ is the optical on-axis retardation at a light wavelength of 650 nm.

Looking at the optical property measurement results in Table 7, it can be confirmed that the retardation films of Examples 1 to 10 exhibit reverse wavelength dispersion or flat dispersion characteristics.

On the other hand, Comparative Example 2 had a problem in that the film thickness was thin, but had a constant wavelength dispersibility characteristic.

In addition, in the case of Comparative Example 1, the reverse wavelength dispersion is high, but the polarization microscope image (200 times) of the film prepared in Example 1 and Comparative Example 1 in A (Example 1) and B (Comparative Example 1) of FIG. ), and looking at this, in the case of Comparative Example 1, it can be confirmed that disclination, which is an alignment defect, has occurred. In contrast, it was confirmed that the film of Example 1 did not have such defects.

In addition, in the case of Comparative Example 3 using an excessive amount of chiral dopant, there was a very high twist angle exceeding 70 °.

Production Example 1: Production of circular polarizing film

After applying a transparent adhesive film (OCA, Optically Clear Adhesive) on top of the stretched polarizer (manufacturer: LG Chem) with a thickness of 200 μm and forming an adhesive layer, the retardation film prepared in Example 1 was laminated on top of the adhesive layer and A circular polarizer was prepared by drying.

Preparation Example 2

In the circular polarizing film of Preparation Example 1, a 0.9 μm-thick C plate (manufacturer: Clap Co., Ltd.) was laminated under the retardation film to prepare a circular polarizer.

The C plate satisfies the refractive index of Equation 6 below, and has a thickness direction retardation (R _th ) of -80 to -83 nm.

[Equation 6]

n _z > n _x ≒ n _y

In Equation 6, n _x is the refractive index in the direction in which the refractive index in the plane in the slow axis direction is the maximum, n _y is the refractive index in the direction orthogonal to the slow axis in the plane and in the plane, and n _z means the refractive index in the thickness direction .

Preparation Examples 3 to 7

A circular polarizing film was prepared in the same manner as in Preparation Example 1, but Preparation Examples 3 to 7 were performed using the retardation film of Examples 2 to 6 instead of Example 1 as shown in Table 8 below.

Comparative Preparation Example 1

After applying a transparent adhesive film (OCA, Optically Clear Adhesive) and forming an adhesive layer on top of a 200 μm-thick stretched polarizer (manufacturer: LG Chem), the retardation film prepared in Comparative Example 3 was laminated on top of the adhesive layer and A circular polarizer was prepared by drying.

Experimental Example 2: Measurement of optical properties of circularly polarizing film 2

Simulation measurements (color contour) were performed on the light leakage characteristics of the circular polarizing films of Preparation Examples 1 to 2 and Comparative Preparation Example 1, and simulation measurement data, frontal reflectivity, lateral reflectance simulator data and thickness direction retardation (R _th ) is shown in Table 8 below.

In addition, the optical axis angles of the retardation film and the polarizer of Preparation Examples 1 to 7 and Comparative Preparation Example 1 were measured, and the results are shown in Table 8 below.

division phase difference
film circular polarization film
reflectivity phase difference film
polarizer
optical axis angle face side
(measurement standard:
q=50, f=45 degrees) Preparation Example 1 Example 1 0.002218 0.010084 25° (±0.2°) Preparation Example 2 Example 1 0.000223 0.006015 - Preparation Example 3 Example 2 0.002000 0.007696 - Production Example 4 3 in implementation 0.002124 0.008762 - Preparation Example 5 Example 4 0.002306 0.011083 - Preparation Example 6 Example 5 0.002364 0.011544 - Preparation Example 7 Example 6 0.002281 0.009082 22° (±0.2°) Comparative Preparation Example 1 Comparative Example 3 0.002473 0.012091 45° (±0.2°)

Looking at the physical property measurement results in Table 8, it was confirmed that the circular polarizing films prepared in Preparation Examples 1 to 7 had very excellent antireflection with a frontal reflectance of 0.002400 or less and a side reflectance of 0.012000 or less. In addition, Preparation Example 2 in which the C plate was formed showed lower reflectivity measurement results on both the front and side surfaces than Preparation Example 1, and through this, it was confirmed that the antireflection effect was increased during the formation of the C plate.

And, looking at Preparation Examples 1 to 7, as the amount of the constant wavelength liquid crystal used in the retardation film increased, the value of the lateral reflectance increased, so the antireflection effect tended to decrease.

In addition, Comparative Preparation Example 1 prepared with a retardation film without using a chiral dopant showed a relatively poor antireflection effect, although the thickness of the retardation film itself was thin compared to Preparation Examples 1 and 2, and the optical axis Angle values tended to be high.

Although the preferred embodiments of the present invention have been described and illustrated using specific terms above, such terms are only used to clearly explain the present invention, and the embodiments and described terms of the present invention are the technical spirit and scope of the following claims. It is obvious that various changes and changes can be made without departing from the scope. Such modified embodiments should not be individually understood from the spirit and scope of the present invention, and should be said to fall within the scope of the claims of the present invention.

Reference Numerals 1: reflective layer (display unit) 10: retardation film
12: QWP film (r-AQWP film or flat dispersion film) 14: HWP film
20: polarizer 30: C plate layer
100: achromatic circular polarization film

Claims (15)

A retardation film including a liquid crystal layer and an optical alignment layer and a polarizer on top of the retardation film,
The retardation film includes a quarter-wavelength film containing liquid crystal having a twist angle of 40 ° to 70 °,
The quarter-wavelength film includes a reverse wavelength dispersion film or a flat wavelength dispersion film,
The quarter-wavelength film is an achromatic circular polarizing film, characterized in that it satisfies the retardation on the optical axis of Equations 1 and 2 below;
[Equation 1]
0.825 ≤ α ≤ 1.045
[Equation 2]
0.965 ≤ β ≤ 1.205
In Equations 1 and 2, α is R ₄₅₀ /R ₅₅₀ , β is R ₆₅₀ /R ₅₅₀ , R ₄₅₀ denotes an optical axial retardation at a light wavelength of 450 nm, R ₅₅₀ denotes an optical axial retardation at a light wavelength of 450 nm, and R ₆₅₀ denotes an optical axial retardation at a light wavelength of 650 nm.
The method of claim 1, wherein the photo-alignment layer includes an photo-alignment compound,
The optical alignment compound is an achromatic circularly polarizing film, characterized in that it comprises a liquid crystal optical alignment agent, characterized in that it comprises a polymer containing a repeating unit represented by the following formula (1);
[Formula 1]

In Formula 1, R ¹ is a hydrogen atom or an alkyl group of C ₁ to C ₃ , A is -OR ³ -, -NHR ³ - or -SR ³ -, and R ³ is a C ₂ to C ₅ linear alkyl group. Ren's group, and R ² is

or

And, R ⁴ is C ₁ ~ C ₁₀ straight-chain alkyl group, C ₃ ~ C ₁₀ branched alkyl group, C ₂ ~ C ₁₀ straight-chain heteroalkyl group in which at least one carbon atom is substituted with a hetero atom, or one carbon atom The above is a C ₃ ~ C ₁₀ branched heteroalkyl group substituted with a hetero atom, m is an integer satisfying the weight average molecular weight of the polymer of 1,000 to 1,000,000, n is an integer from 0 to 20, and * denotes a bonding site. .
According to claim 2,
The polymer is an achromatic circularly polarizing film, characterized in that it comprises a liquid crystal optical alignment agent characterized in that it comprises a copolymer further comprising a repeating unit represented by the formula (1) and a repeating unit represented by the following formula (2);
[Formula 2]

In Formula 2, R ¹ is a hydrogen atom or a C ₁ ~ C ₃ alkyl group, and R ⁵ is a C ₁ ~ C ₁₀ straight-chain alkyl group, a C ₃ ~ C ₁₀ branched alkyl group, or a hetero atom having at least one carbon atom. A C ₂ ~ C ₁₀ straight-chain heteroalkyl group substituted with atoms, a C ₃ ~ C ₁₀ branched heteroalkyl group in which at least one carbon atom is substituted with a hetero atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted phenoxy group, or A substituted or unsubstituted N-phenylamino group, and L is an integer of 1 to 20.
The method of claim 2, wherein the liquid crystal photo-alignment agent includes the photo-alignment compound and a solvent,
The solvent is a non-polar solvent containing at least one selected from benzene, toluene, ethyl acetate, butyl acetate, tetrahydrofuran (THF), PGMEA (Propylene glycol methyl ether acetate), dichloromethane, and chloroform; and
a polar solvent containing at least one selected from cyclopentanone, cyclohexanone, acetone, dimethylformamide (DMF), and acetonitrile; An achromatic circularly polarizing film comprising at least one selected from among.
The achromatic circularly polarizing film according to claim 1, wherein R ₅₅₀ is 120 to 150 nm.
The method of claim 1, wherein the optical axis angle between the polarizer and the retardation film is 20 ° to 40 °,
The quarter wave film is an achromatic circular polarizing film, characterized in that the thickness of 2.5 ~ 3.8 ㎛.
The method of claim 1, wherein the liquid crystal layer is formed of a liquid crystal resin containing a polymerizable liquid crystal compound and a chiral dopant,
The polymerizable liquid crystal compound is an achromatic circularly polarizing film, characterized in that it comprises a reverse wavelength liquid crystal compound having a refractive index of Equation 3 and a forward wavelength liquid crystal compound having a refractive index of Equation 4 below;
[Equation 3]
0.040 ≤ │Δn ₁ │ ≤ 0.065
[Equation 4]
0.100 ≤ │Δn ₂ │ ≤ 0.150
In Equations 3 and 4, Δn ₁ and Δn ₂ respectively mean the difference between the refractive index of extraordinary light (n _e ) and the refractive index of normal light (n _o ).
The achromatic circularly polarizing film according to claim 7, wherein the polymerizable liquid crystal compound comprises the reverse wavelength liquid crystal compound and the forward wavelength liquid crystal compound in a weight ratio of 1:0.05 to 0.55.
The achromatic circular polarizing film according to claim 1, further comprising a C plate layer on the other side of the retardation film on which the polarizer is stacked, or further comprising a C plate layer between the polarizer and the retardation film.
The achromatic circularly polarizing film according to claim 1, wherein the retardation film further comprises a half-wavelength film under or above the quarter-wavelength film.
8. The method of claim 7, wherein the C plate layer includes a homeotropic liquid crystal polymer film, and an achromatic circularly polarized film that satisfies the refractive index of Equation 6;
[Equation 6]
n _z > n _x ≒ n _y
In Equation 6, n _x is the refractive index in the direction in which the refractive index in the plane in the slow axis direction is the maximum, n _y is the refractive index in the direction orthogonal to the slow axis in the plane and in the plane, and n _z means the refractive index in the thickness direction .
The achromatic circularly polarizing film according to claim 9, wherein the C plate layer has a thickness direction retardation (R _th ) of -120 to -30 nm according to Equation 1 below;
[Equation 1]
_Rth = {(n _x +n _y )/2 - n _z }×d
In Equation 1, n _x is the refractive index in the direction in which the refractive index in the plane in the slow axis direction is the maximum, n _y is the refractive index in the direction orthogonal to the slow axis in the plane and in the plane, n _z is the refractive index in the thickness direction, d is is the thickness of the film.
A quarter-wavelength film having a thickness of 2.50 to 3.80 μm and a liquid crystal twist angle of 40 ° to 70 °,
The quarter-wavelength film includes a liquid crystal layer and an optical alignment layer,
The quarter-wavelength film is a retardation film for an achromatic circular polarizing film, characterized in that the reverse wavelength dispersion film or flat wavelength dispersion film.
An antireflection film for a display comprising the circular polarizing film of any one of claims 1 to 13.
The antireflection film for a display according to claim 14, wherein the display is an Organic Light Emitting Diodes (OLED) display or a Micro LED (Light Emitting Diodes) display.

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