KR20090045836A - Curable resin composition for prism film and prism film - Google Patents

Abstract

The present invention is an ultraviolet curable (meth) acrylate monomer (A) represented by the following formula (1), an ultraviolet curable (meth) acrylate monomer (B) represented by the following formula (2), a polyfunctional (meth) acrylate monomer (C) It provides the cured resin composition for prism layer formation of the prism film containing one or more photoinitiator (D).

 (Formula 1)

(Formula 2)

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , Ar, X, Y, m, n are as defined in the specification.)

High refractive index, prism, UV curable monomer

Description

Curable Resin Composition and Prism Film for Prism Layer Formation

FIELD OF THE INVENTION The present invention relates to photocurable resin compositions which are cured rapidly by irradiation with ultraviolet light, in particular photocurable resin compositions useful for producing optical components such as lenses, optical discs, prisms and lens sheets in mold polymerization. The resin composition is also suitable for use as a surface coating material for plastic film substrates used in optical materials such as liquid crystal display device substrates.

The prism sheet for improving the front brightness of the backlight unit used in the liquid crystal display device is molded into a specific shape from a transparent material having a specific refractive index. In the method of manufacturing a prism sheet, the said patent has the method of integrally molding using the transparent glass which has a refractive index of a specific range, the method of shape | molding a prism shape from UV curable resin composition, etc. Plastic materials typified by the UV curable resins can be used only in limited applications for heat resistance. That is, if a representative lens sheet of a prism sheet obtained from a conventional UV curable resin is used in a high temperature environment, part of the lens sheet is fused on the surface of the backlight, leaving a sticky trace. This is a fatal flaw that adversely affects the optical performance of the product. Moreover, attention has been paid to liquid crystal display elements using plastic films as substrates instead of glass substrates in view of producing thinner and larger liquid crystal cells having curved display surfaces. However, when a plastic film is used as the substrate, the outer surface of the substrate is easily damaged, damaging its appearance, causing irregular reflections, and being damaged. This adversely affects the optical characteristics of the liquid crystal display device. For this reason, a coating layer of a UV curable resin is provided on the surface of the substrate to increase the hardness of the substrate surface, thereby obtaining a liquid crystal display device in which the surface is hardly damaged.

However, if the coating layer is formed using a conventional UV curable resin, the obtained image is darker than the image obtained from the liquid crystal display device using the glass substrate due to insufficient transparency, light coloring resistance, etc., and the quality is degraded.

 The present invention provides a cured resin composition for forming a prism layer having excellent productivity, high transparency, high refractive index of a cured product, high surface hardness, excellent dimensional accuracy, and excellent heat resistance, in order to improve the disadvantages of the prior art. The purpose is to provide.

The present invention for achieving the above object is an ultraviolet curable (meth) acrylate monomer (A) represented by the following formula (1), ultraviolet curable (meth) acrylate monomer (B) represented by the following formula (2), polyfunctional ( It provides the cured resin composition for prism layer formation of the prism film characterized by including a meta) acrylate monomer (C) and 1 or more photoinitiator (D).

 (Formula 1)

(X is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, Y is an oxygen atom or a sulfur atom, R ₁ is an aliphatic or aromatic hydrocarbon having 1 to 30 carbon atoms, with or without heterocycle, R ₂ and R ₃ Are each independently hydrogen, a halogen element, a cyano group, a nitro group, or an aliphatic or aromatic hydrocarbon having 1 to 30 carbon atoms containing at least one sulfur element or oxygen atom in the molecule, or an aliphatic hydrocarbon having 1 to 30 carbon atoms, without substituents. Or aromatic hydrocarbons.)

(Formula 2)

(X is an oxygen atom or a sulfur atom, R ₄ is an alkylene group or a hydroxyalkylene group having 2 to 6 carbon atoms, R ₅ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms and Ar is an aromatic hydrocarbon having 6 to 30 carbon atoms) M is an integer of 0 or 1, and n is an integer of 0 to 10.

Moreover, the said ultraviolet curable (meth) acrylate monomer (A) is a urethane with the compound which has one or more isocyanate groups in a molecule | numerator in 3- (biphenyl-2-yloxy) -2-hydroxypropyl (meth) acrylate. It provides the cured resin composition for prism layer formation of the prism film obtained by the coupling reaction and containing (meth) acrylate whose refractive index is 1.5 or more.

In addition, the said ultraviolet curable (meth) acrylate monomer (A) is obtained by the urethane bond reaction with the compound which has one or more isocyanate groups in a molecule | numerator in 2-hydroxy-3-phenylsulfanylpropyl (meth) acrylate. It provides the cured resin composition for prism layer formation of the prism film characterized by including (meth) acrylate whose refractive index is 1.5 or more.

In addition, the compound having an isocyanate group may be 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1,8-diisocyanatooctane, 1,12-diisocyanatodecane, 1,5-diisocyanate NATO-2-methylpentane, trimethyl-1,6-diisocyanatohexane, 1,3-bis (isocyanatomethyl) cyclohexane, trans-1,4-cyclohexene diisocyanate, 4,4'-methylenebis (Cyclohexyl isocyanate), isophorone diisocyanate, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, xylene-1,4-diisocyanate, tetramethylxylene-1,3- From diisocyanate, 1, -chloromethyl-2,4-diisocyanate, 4,4'-methylenebis (2,6-dimethylphenylisocyanate), 4,4'-oxybis (phenylisocyanate), hexamethylene diisocyanate With trifunctional isocyanates derived, trimethanepropanol adduct toluene diisocyanate, etc. It provides a cured resin composition for forming a prism layer of a prism film, characterized in that at least one compound selected from the group consisting of.

The ultraviolet curable (meth) acrylate monomer (B) has a refractive index of 1.5 or more and a (meth) acrylate having a viscosity of 5 to 15000 cps at 25 ° C., for forming a prism layer of a prism film. It provides a cured resin composition.

In addition, R ₄ of the general formula (2) provides a cured resin composition for forming a prism layer of a prism film, characterized in that 1,2-ethylyl or 2-hydroxy-1,3-propylyl.

In addition, the polyfunctional (meth) acrylate monomer (C) is a prism characterized by using bisphenol A type, or bisphenol F type and bisphenol AD type glycidyl (meth) acrylate in order to improve adhesion to the substrate. The cured resin composition for prism layer formation of a film is provided.

In addition, 10 to 70 parts by weight of the compound of the ultraviolet curable (meth) acrylate monomer (A) represented by the formula (1) relative to 100 weight of the composition, the ultraviolet curable (meth) acrylate monomer (B) represented by the formula (2) 10 to 60 parts by weight of the compound, 5 to 50 parts by weight of the polyfunctional (meth) acrylate monomer (C), 0.1 to 10 parts by weight of the photoinitiator (D) is formed of a prism layer of the prism film The curable resin composition for is provided.

The present invention also provides a prism film comprising a prism layer formed of the above-described composition on one surface of the transparent base film.

The present invention also provides a backlight unit comprising the above-described prism film.

The present invention also provides a liquid crystal display device having the above-described backlight unit.

Hereinafter, the present invention will be described in more detail. The following detailed description is a description of an embodiment, and therefore, although limited and assertive, does not limit the scope of rights defined by the claims.

The cured resin composition for prism layer formation of the prism film of this invention is the ultraviolet curable (meth) acrylate monomer (A) represented by following formula (1), the ultraviolet curable (meth) acrylate monomer (B) represented by following formula (2), It is characterized by including a polyfunctional (meth) acrylate monomer (C) and one or more photoinitiators (D).

(Formula 1)

(X is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, Y is an oxygen atom or a sulfur atom, R ₁ is an aliphatic or aromatic hydrocarbon having 1 to 30 carbon atoms, with or without heterocycle, R ₂ and R ₃ Are each independently hydrogen, a halogen element, a cyano group, a nitro group, or an aliphatic or aromatic hydrocarbon having 1 to 30 carbon atoms containing at least one sulfur element or oxygen atom in the molecule, or an aliphatic hydrocarbon having 1 to 30 carbon atoms, without substituents. Or aromatic hydrocarbons.)

Although not limited, the (meth) acrylate monomer (A) represented by the formula (1) may be used in oxirane compounds such as 2- (biphenyl-2-yloxymethyl) oxirane and 2-phenylsulfanylmethyloxirane ( The (meth) acrylate obtained by reacting with meta) acrylic acid can be obtained through a urethane bond with a compound containing at least one isocyanate group in a molecule, and the compound containing an isocyanate group is 1,4-diisocyanatobutane, 1, 6-diisocyanatohexane, 1,8-diisocyanatooctane, 1,12-diisocyanatodecane, 1,5-diisocyanato-2-methylpentane, trimethyl-1,6-diisocyanatohexane, 1 , 3-bis (isocyanatomethyl) cyclohexane, trans-1,4-cyclohexene diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, toluene-2,4-diisocyanate , Toluene-2,6-diisocyanate, xylene-1,4-di Isocyanate, tetramethylxylene-1,3-diisocyanate, 1, -chloromethyl-2,4-diisocyanate, 4,4'-methylenebis (2,6-dimethylphenylisocyanate), 4,4'-oxy It may be selected from the group consisting of bis (phenyl isocyanate), trifunctional isocyanate derived from hexamethylene diisocyanate, trimethane propanol adduct toluene diisocyanate and the like.

The (meth) acrylate monomer (A) is preferably contained in 10 to 70 parts by weight with respect to 100 parts by weight of the composition, when less than 10 parts by weight is difficult to meet the expectation of improving the refractive index, when more than 70 parts by weight There is a problem that the color coordinates worsen after coating.

The ultraviolet curable (meth) acrylate monomer (B) is a (meth) acrylate monomer represented by the following formula (2).

(Formula 2)

(X is an oxygen atom or a sulfur atom, R ₄ is an alkylene group or a hydroxyalkylene group having 2 to 6 carbon atoms, R ₅ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms and Ar is an aromatic hydrocarbon having 6 to 30 carbon atoms) M is an integer of 0 or 1, and n is an integer of 0 to 10.

Although not limited, preferably, a high refractive index material having a refractive index of 1.5 or more and a viscosity at 25 ° C. of 5 to 15000 cps in the (meth) acrylate monomer (B) represented by Chemical Formula 2 is obtained by curing the high refractive index of the prism layer. It is preferable as a substance which forms the prism layer of the prism film which maintains and improves a brightness | luminance, the hardness after hardening, the viscosity is excellent, workability, and especially the adhesive force with a base film is increased.

In addition, the (meth) acrylate monomer (B) is 2-hydroxy-3- ( o -phenylphenoxy) propyl acrylate, 2-hydroxy-3- ( m -phenylphenoxy) propyl acrylate, 2- Hydroxy-3- ( p -phenylphenoxy) propyl acrylate, benzyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, neopentyl glycol benzoate ( At least one (meth) acrylate selected from the group consisting of meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate and 2-phenylsulfanylethyl (meth) acrylate. The cured resin composition for prism layer formation of a prism film is provided.

The (meth) acrylate monomer (B) is preferably contained 10 to 60 parts by weight with respect to 100 parts by weight of the composition, when less than 10 parts by weight, it is difficult to meet the expectations of improving the refractive index and adhesion, more than 60 parts by weight In one case, there is a problem in that the workability is inferior because the viscosity is not easy to adjust.

The polyfunctional (meth) acrylate monomer (C) may be further included in the composition to improve adhesion to the substrate and is mainly from the group consisting of bisphenol A, bisphenol F, bisphenol AD type glycidyl (meth) acrylate It is preferable to use one or more kinds.

The polyfunctional (meth) acrylate monomer (C) is preferably contained 5 to 50 parts by weight with respect to 100 parts by weight of the composition, when less than 5 parts by weight, it is difficult to meet the expectation of improving the adhesion, more than 50 parts by weight In the case of work, there is a problem inferior workability.

The photoinitiator (D) may be used a conventional photoinitiator, selected from the group consisting of a photoinitiator of the phosphine oxide (phospine oxide), propane (propanone), ketone (type) system, formate (formate) system It may be more than one species.

In addition, the photoinitiator (D) is 2-methyl-1- [4- (methylthio) phenyl] 2-morpholinpropanone-1, diphenylketone benzyldimethyl ketal, 2-hydroxy-2-methyl-1- Phenyl-1-one, 4-hydroxy cyclo phenyl ketone, dimethoxy-2-phenylatetophenone, anthraquinone, fluorene, triphenylamine, carbazole, 3-methylacetophenone, 4-knoloacetophenone, Cured resin composition for forming a prism layer of a prism film, which is at least one photoinitiator selected from the group consisting of 4,4-dimethoxyacetophenone, 4,4-diaminobenzophenone, and 1-hydroxycyclohexyl phenyl ketone. To provide.

The photoinitiator preferably contains 0.1 to 10 parts by weight based on 100 parts by weight of the composition. If the amount is less than 0.1 parts by weight, sufficient photocuring may not be achieved, and a blocking phenomenon may occur. If the amount is more than 10 parts by weight, photoinitiators remain after curing, resulting in surface precipitation of residual photoinitiators when left for a long time.

In addition to the above materials, antioxidants, ultraviolet absorbers, light stabilizers, thermal polymerization inhibitors, labelling agents, surfactants, lubricants, and the like may be used together in the cured resin composition for forming the prism layer.

Next, the prism film using the composition for prism layer formation of the said prism film is demonstrated.

The prism film of the present invention is characterized by comprising a prism layer formed on one surface of the transparent base film from the transparent base film and the composition for forming a prism layer of the present invention.

As a method of manufacturing the prism film of the present invention, the composition for forming a prism layer of the present invention is coated on a frame in which a three-dimensional structure (prism structure) having a brightness enhancement function is stamped by a conventionally known method, In the state in which one surface is in contact with the coating surface of the stamp frame, ultraviolet rays are irradiated toward the transparent base film to photocur the composition coated on the frame. Then, by separating the cured coating layer adhered to the transparent substrate film from the engraving frame, it is possible to produce a prism film formed with a prism layer made of the composition for forming a prism layer on one surface of the transparent substrate film.

The compositions of the present invention may also be usefully used for other optical materials such as microstructure-containing optical articles (eg films). Exemplary optical materials include, but are not limited to, optical lenses such as Fresnel lenses, optical films such as high refractive index films, microrepeated films such as fully internal reflective films, light enhancement films, flat panel films, multilayer films, retroreflective sheets, optical fibers or Optical tubes and the like.

The present invention also provides a backlight unit of a liquid crystal display device having the prism film. The backlight unit device is not limited and may employ a structure known in the art. For example, a light diffusion plate, a prism sheet, or the like may be provided on a light guide plate for guiding light of a light source and a light source such as an LED, and an upper surface of the light guide plate. It is preferable that the said prism sheet is a prism film mentioned above.

Finally, another embodiment of the present invention is a liquid crystal display device comprising the above-mentioned backlight unit device. The prism film of the present invention can be preferably used in reflective, transmissive, semi-transmissive LCD or LCD of various driving methods such as TN type, STN type, OCB type, HAN type, VA type, and IPS type. In addition, the prism film of the present invention can be preferably used for various display devices such as a plasma display, a field emission display, an organic EL display, an inorganic EL display, and an electronic paper.

The present invention provides a composition for forming a prism layer having a high refractive index, having a viscosity characteristic that is easy to form a prism layer of a prism film, improving surface hardness and adhesion with the base film after forming the prism film, and having excellent brightness. do.

The present invention will be further illustrated by the following examples, which are only specific examples of the present invention, and are not intended to limit or limit the protection scope of the present invention.

 Synthesis Example 1 Glycidyl (meth) acrylate Synthesis

230 g of 2-phenylglycidylphenol, 69 g of acrylic acid, 5 g of tetrabutylammonium bromide, and 0.1 g of 4-methoxyphenol were added to a 1 L flask equipped with a condenser, and the temperature was raised to 90 ° C., followed by stirring for 12 hours. The reaction was terminated at 0.1 or less by measuring the acid value.

Synthesis Example 2 Glycidyl (meth) acrylate Synthesis

230 g of sulfanyl glycidylphenol, 80 g of acrylic acid, 5 g of tetrabutylammonium bromide, and 0.1 g of 4-methoxyphenol were added to a 1 L flask equipped with a condenser, and the temperature was raised to 90 ° C., followed by stirring for 12 hours. The reaction was terminated at 0.1 or less by measuring the acid value.

 Synthesis Example 3 Synthesis of Multifunctional (meth) acrylate with Urethane Bond

Into a 1 L flask equipped with a condenser, 300 g of glycidyl (meth) acrylate prepared in Synthesis Example 1, 50 g of 2,4-diisocyanatotoluene and 2 g of dibutyltin laurate were added, and the temperature was raised to 60 ° C., followed by 3 Stirred for hours. Termination of the reaction was terminated by disappearance of the isocyanate characteristic peak of 1720Cm ^{−1 as} a result of IR analysis.

Synthesis Example 4 Synthesis of polyfunctional (meth) acrylate with urethane bond

Into a 1 L flask equipped with a condenser, 300 g of glycidyl (meth) acrylate prepared in Synthesis Example 2, 40 g of 2,4-diisocyanatotoluene and 1.5 g of dibutyltin laurate were added and the temperature was raised to 60 ° C. Stir for 3 hours. Termination of the reaction was terminated by disappearance of the isocyanate characteristic peak of 1720Cm ^{−1 as} a result of IR analysis.

As an embodiment of the composition of the present invention, each composition and composition ratio are shown in Table 1 below.

<Table 1>

ingredient Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Comparative Example 1 Comparative Example 2 Comparative Example 3 UV Curing Monomer Synthesis Example 3 25 30 40 50 Synthesis Example 4 25 30 40 UV curing monomer (a) 15 20 17 13 15 20 17 45 37.5 UV curable monomer (b) 15 10 13 17 15 10 13 25 UV curable monomer (c) 40 35 25 15 40 35 25 35 High refractive monomer (a) 37.5 37.5 45 High refractive monomer (b) 12.5 12.5 Photoinitiator Oxy-phenyl-acetic 2- [2-hydroxy-ethoxy] ethyl ester 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 Diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5

Synthesis Example 3: 3- (biphenyl-2-yloxy) -2-hydroxypropyl acrylate

Synthesis Example 4 2-hydroxy-3-phenylsulfanylpropyl acrylate

UV-curable monomer (a): 2-hydroxy-3- ( o -phenylphenoxy) propyl acrylate

UV curing monomer (b): 2-phenoxyethyl acrylate

UV-curing monomer (c): bisphenol A glycidyl ether acrylate

High refractive monomer (a): fluorene ethyl acrylate

High refractive monomer (b): acryloyl morpholine

Evaluation methods for the above examples are as follows.

(1) Viscosity Evaluation of Composition

The viscosity at 25 ° C. was measured using a rotational viscometer according to JIS K7117.

(2) refractive index evaluation of the composition

The refractive index is measured using a refractometer (model name: 1T, Japan ATAGO ABBE) to measure the refractive index of the composition. The light source for the measurement was a D-beam sodium lamp of 589.3 nm.

(3) Adhesive force evaluation (falling number / 100)

After coating the composition on the transparent PET base film, applying a pressure to the thickness of 3㎛ by superimposing a smooth metal plate on the surface, and then cured to remove the metal plate, only 100 of the cured thickness within the area of 10 × 10 ㎜ After the incision into the matrix structure, the number of stripped matrices is indicated while adhering the tape thereon and strongly releasing vertically.

(4) mountain separation

After mounting the coated film on the 17-inch backlight unit as shown in No. 2, the backlight unit is mounted on a device that reciprocates 60 times per minute and reciprocates for 10 hours. If it is very bad, if it is 7-9 places, if it is bad, if it is 4-6 places, if it is 1 ~ 3, it is good, if not, it is classified as good.

(4) pencil hardness

Pencil hardness was measured using a pencil hardness tester (PHT, manufactured by Seokbo Science, Inc.) under a 500g load. The pencil was made 5 times per pencil hardness using Mitsubishi products. If there were two or more gases, it was determined to be defective.

Kiss: 0 OK

Kiss: 1 OK

Ges: 2 or more NG

(6) curling

The sample cut into the square shape of A4 size (29.7 X 21.0 cm) was placed on a flat glass plate with the coated surface of the film facing up, and the distance from the square glass plate was measured at 25 ° C. and 50% RH, and then averaged. Was taken as a measured value.

Very good: 0 to 15 mm, good: 15 to 30 mm, poor: 30 to 50 mm, very poor: more than 50 mm.

The results evaluated by the above-described evaluation result method of the composition is shown in Table 2-1 and Table 2-2.

<Table 2-1>

Example One 2 3 4 5 6 7 Viscosity (cps / 25 ℃) 770 856 900 950 856 900 800 Refractive index 1.547 1.544 1.548 1.543 1.544 1.548 1.547 Adhesion 0/100 0/100 0/100 0/100 0/100 0/100 0/100 Mountain crossing Very good Very good Good Good Very good Good Good Pencil hardness 3H 3H 2H 2H 3H 2H 2H curling Very good Good Good Good Good Good Good

<Table 2-2>

Comparative example One 2 3 Viscosity (cps / 25 ℃) 750 692 562 Refractive index 1.551 1.536 1.531 Adhesion 2/100 0/100 3/100 Mountain crossing Bad Bad Bad Pencil hardness 2H 1H 1H curling Bad Bad Very bad

Claims (11)

UV-curable (meth) acrylate monomer (A) represented by the following formula (1), UV-curable (meth) acrylate monomer (B) represented by the following formula (2), polyfunctional (meth) acrylate monomer (C), one The above photoinitiator (D) is included, The cured resin composition for prism layer formation of the prism film characterized by the above-mentioned. (Formula 1)

(X is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, Y is an oxygen atom or a sulfur atom, R ₁ is an aliphatic or aromatic hydrocarbon having 1 to 30 carbon atoms, with or without heterocycle, R ₂ and R ₃ Are each independently hydrogen, a halogen element, a cyano group, a nitro group, or an aliphatic or aromatic hydrocarbon having 1 to 30 carbon atoms containing at least one sulfur element or oxygen atom in the molecule, or an aliphatic hydrocarbon having 1 to 30 carbon atoms, without substituents. Or aromatic hydrocarbons.) (Formula 2)

(X is an oxygen atom or a sulfur atom, R ₄ is an alkylene group or a hydroxyalkylene group having 2 to 6 carbon atoms, R ₅ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms and Ar is an aromatic hydrocarbon having 6 to 30 carbon atoms) M is an integer of 0 or 1, and n is an integer of 0 to 10. The method of claim 1, wherein the ultraviolet curable (meth) acrylate monomer (A) is a 3- (biphenyl-2-yloxy) -2-hydroxypropyl (meth) acrylate having at least one isocyanate group in a molecule. Cured resin composition for prism layer formation of the prism film obtained by the urethane bond reaction with a compound, and containing (meth) acrylate whose refractive index is 1.5 or more. The urethane bond reaction of claim 1, wherein the ultraviolet curable (meth) acrylate monomer (A) is a 2-hydroxy-3-phenylsulfanylpropyl (meth) acrylate with a compound having at least one isocyanate group in a molecule thereof. Cured resin composition for prism layer formation of the prism film characterized by including the (meth) acrylate of refractive index 1.5 or more obtained by the thing. The compound according to claim 2, wherein the compound having an isocyanate group is 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1,8-diisocyanatooctane, 1,12-diisocyanatodecane, 1, 5-diisocyanato-2-methylpentane, trimethyl-1,6-diisocyanatohexane, 1,3-bis (isocyanatomethyl) cyclohexane, trans-1,4-cyclohexene diisocyanate, 4,4 '-Methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, xylene-1,4-diisocyanate, tetramethylxylene-1, 3-diisocyanate, 1, -chloromethyl-2,4-diisocyanate, 4,4'-methylenebis (2,6-dimethylphenylisocyanate), 4,4'-oxybis (phenylisocyanate), hexamethylenedi Trifunctional Isocyanates Derived from Isocyanates, Trimethanepropanol Adduct Toluenediisocyanae One or more selected compounds of the prism layer to form the cured resin composition of the prismatic film, which is characterized from the group consisting of and the like. The prism film of claim 1, wherein the ultraviolet curable (meth) acrylate monomer (B) comprises a (meth) acrylate having a refractive index of 1.5 or more and a viscosity at 25 ° C of 5 to 15000 cps. Cured resin composition for prism layer formation The cured resin composition for forming a prism layer according to claim 1, wherein R ₁ in Chemical Formula 2 is 1,2-ethylyl or 2-hydroxy-1,3-propylyl. The method according to claim 1, wherein the polyfunctional (meth) acrylate monomer (C) uses bisphenol A type, or bisphenol F type and bisphenol AD type glycidyl (meth) acrylate to improve adhesion with the substrate. Cured resin composition for prism layer formation of the prism film characterized by the above-mentioned. According to claim 1, 10 to 70 parts by weight of the compound of the ultraviolet curable (meth) acrylate monomer (A) represented by the formula (1) relative to 100 weight of the composition, the ultraviolet curable (meth) acrylate represented by the formula (2) 10 to 60 parts by weight of the compound of the monomer (B), 5 to 50 parts by weight of the polyfunctional (meth) acrylate monomer (C), 0.1 to 10 parts by weight of the photoinitiator (D) comprises a prism film Cured resin composition for forming a prism layer. A prism film comprising a prism layer formed of the composition of any one of claims 1 to 8 on one surface of the transparent base film. A backlight unit comprising the prism film of claim 9. A liquid crystal display device comprising the backlight unit of claim 10.