KR102237002B1 - Composite optical film and display apparatus comprising the same - Google Patents

Abstract

The present invention includes a first optical layer including a first optical pattern, a second optical layer formed on the first optical layer and including a second optical pattern, and a buffer layer formed between the first optical layer and the second optical layer. It includes, and relates to a composite optical film having a modulus of the buffer layer of 1 MPa to 100 MPa.

Description

Composite optical film and display apparatus comprising the same

The present invention relates to a composite optical film and a display device including the same.

The liquid crystal display device includes a backlight unit including a light source, a light guide plate, a prism sheet, a diffusion sheet, and the like. Recently, an attempt to thin the backlight unit continues.

The composite optical film is made by laminating an upper optical sheet and a lower optical sheet on which a prism is formed with an adhesive layer to be integrated, and has an effect of thinning the backlight unit. The prism pattern of the lower optical sheet has a structure in which the upper part penetrates the adhesive layer, and since it is a laminated sheet structure, there is a risk of separation between sheets. It can be damaged.

The background technology of the present invention is disclosed in Korean Patent Registration No. 10-1155876.

The problem to be solved by the present invention is to provide a composite optical film having excellent impact resistance.

Another problem to be solved by the present invention is to provide a composite optical film without separation between the laminated sheets during cutting.

Another problem to be solved by the present invention is to provide a composite optical film in which the damage of the mountain portion of the lower prism pattern is reduced.

A composite optical film according to an aspect of the present invention includes a first optical layer including a first optical pattern, a second optical layer formed on the first optical layer and including a second optical pattern, and a first optical layer and a second optical layer. A buffer layer formed between layers may be included, and a modulus of the buffer layer may be 1 MPa to 100 MPa.

A display device according to another aspect of the present invention may include the composite optical film.

The composite optical film of the present invention may have excellent impact resistance.

The composite optical film of the present invention may not have separation between the laminated sheets at the time of cutting.

In the composite optical film of the present invention, damage to the peaks of the lower prism pattern may be reduced.

1 is a cross-sectional view of a composite optical film according to an embodiment of the present invention.
2 is a cross-sectional view of a composite optical film according to another embodiment of the present invention.
3 is a perspective view of a liquid crystal display according to an exemplary embodiment of the present invention.

Hereinafter, specific examples of the present application will be described in more detail with reference to the accompanying drawings. However, the technology disclosed in the present application is not limited to the specific examples described herein and may be embodied in other forms. However, the embodiments introduced herein are provided so that the disclosed content may be thorough and complete, and the spirit of the present application may be sufficiently conveyed to those skilled in the art. In the drawings, in order to clearly express each component, the size of the component, such as width or thickness, is slightly enlarged. In addition, although only some of the constituent elements are shown for convenience of description, those skilled in the art will be able to easily grasp the remaining parts of the constituent elements. In addition, those of ordinary skill in the relevant field will be able to implement the spirit of the present application in various other forms within the scope of the technical spirit of the present application.

In the present specification, "upper part" and "lower part" are defined based on the drawings, and "upper part" may be changed to "lower part" and "lower part" may be changed to "upper part" according to the viewpoint of the view, and "on" or What is referred to as “on” may include a case where other structures are interposed not only above but also in the middle. On the other hand, what is referred to as "directly on" or "directly on" indicates that no other structure is intervened.

In the present specification, "(meth)acrylic" means acrylic and/or methacrylic.

In the present specification, "oligomer" means that the number of repeating units is at least 2 and not a polymer.

Hereinafter, a composite optical film according to an embodiment of the present invention will be described with reference to FIG. 1. 1 is a schematic diagram showing a cross section of a composite optical film according to an embodiment of the present invention.

The composite optical film according to an embodiment of the present invention is formed on the first optical layer 110 including the first optical pattern 112, the first optical layer 110, and includes the second optical pattern 122. A second optical layer 120 and a buffer layer 130 formed between the first optical layer 110 and the second optical layer 120 may be included.

The first optical layer 110 may include a first base layer 111 and a first optical pattern 112 formed on the first base layer 111. The first optical layer may play a role of changing a path of light that is incident through the light incidence surface by the lower surface as the light incidence surface and the upper surface as the light-exiting surface to emit light by changing a path of light through the light-exiting surface as the upper surface.

The first base layer 111 may include a thermoplastic resin, and the thermoplastic resin includes a polyester resin, a polycarbonate resin, a polyacetal resin, an acrylic resin, a styrene resin, a vinyl resin, a polyphenylene ether resin, Acyclic polyolefin resin, cycloolefin resin, acrylonitrile-butadiene-styrene copolymer resin, polyacrylate resin, polyarylsulfone resin, polyether sulfone resin, polyphenylene sulfide resin, fluorine resin, etc. However, it is not limited thereto. The thickness of the first base layer 111 may be 10 to 300 μm, specifically 10 to 100 μm, but is not limited thereto.

The first optical pattern 112 may be formed on one surface of the first base layer 111 and may serve to increase luminance by condensing incident light incident from the lower surface. The first optical pattern 112 may include a prism pattern having a triangular cross section or a polygon having 4 to 10 sides, a microlens pattern, a lenticular lens, an emboss pattern, or a combination thereof. In FIGS. 1 and 2, the first optical pattern 112 is illustrated as a prism having a triangular cross section, but this is only an example and is not limited thereto.

Specifically, the first optical pattern 112 may be a prism pattern having a triangular cross section, and specifically, may be a prism pattern for high luminance. For example, the apex angle of the prism pattern may be 70° to 110°, and there may be an effect of improving luminance within the above range.

The height H of the first optical pattern 112 may be 5 μm to 100 μm, specifically 10 μm to 30 μm, but is not limited thereto. The pitch of the first optical pattern 112 may be 10 μm to 200 μm, specifically 20 μm to 60 μm, but is not limited thereto.

In the first optical pattern 112, a convex portion of an upper portion of the pattern may be partially inserted into the buffer layer 130. The depth at which the first optical pattern 112 is inserted into the buffer layer 130 may be, for example, greater than 0 and 20% or less, specifically 5% to 10% of the height H of the first optical pattern 112. Within the above range, the first optical layer 110 and the second optical layer 120 are not separated, and luminance deterioration can be prevented. The depth at which the first optical pattern 112 is inserted into the buffer layer 130 is vertical from the lower surface of the second base layer 121 of the second optical layer 120 to the upper vertex of the first optical pattern 112 to be described later. It may be 3 μm to 10 μm in length, but is not limited thereto.

In this specification, "insertion" means that the upper convex portion of the first optical pattern 112 penetrates the buffer layer 130 and exists inside the buffer layer 130, and "vertex" is the height of the first optical pattern 112 Means the highest point.

The first optical pattern 112 may be formed of a composition including an ultraviolet-curable unsaturated compound and an initiator, or may be formed of the same or different material as the first base layer 111. As an example, UV-curable unsaturated compounds are epoxy (meth) acrylate, urethane (meth) acrylate, phenylphenol ethoxylated (meth) acrylate, trimethylolpropane ethoxylated (meth) acrylate, phenoxy Benzyl (meth)acrylate, phenylphenoxyethyl (meth)acrylate, ethoxylated thiodiphenyl di(meth)acrylate, phenylthioethyl (meth)acrylate monomers or oligomers thereof, or fluorene derivatives unsaturated It may include a resin, but is not limited thereto. The initiator may be a ketone-based, phosphine oxide-based, phosphorus-based, triazine-based, acetophenone-based or benzophenone-based photopolymerization initiator, but is not limited thereto.

The second optical layer 120 is formed on the first optical layer 110 and includes a second base layer 121 and a second optical pattern 122 formed on one surface of the second base layer 121. I can. The second optical layer 120 is incident from the first optical layer 110 through the light incidence surface by the lower surface as the light incidence surface and the upper surface as the light-exiting surface, and passes the path of light through the light-exiting surface as the upper surface. It can play a role to change and display.

The second base layer 121 may include a thermoplastic resin, and the thermoplastic resin is a polyester resin, a polycarbonate resin, a polyacetal resin, an acrylic resin, a styrene resin, a vinyl resin, a polyphenylene ether resin, Acyclic polyolefin resin, cycloolefin resin, acrylonitrile-butadiene-styrene copolymer resin, polyacrylate resin, polyarylsulfone resin, polyether sulfone resin, polyphenylene sulfide resin, fluorine resin, etc. However, it is not limited thereto. The thickness of the second base layer 121 may be 10 to 300 μm, specifically 10 to 100 μm, but is not limited thereto.

The second optical pattern 122 may include a pattern for changing a path of light incident from the first optical layer 110. For example, the second optical pattern 122 may include a prism pattern having a triangular cross section or a polygon having 4 to 10 sides, a microlens pattern, a lenticular lens, an emboss pattern, or a combination thereof.

The height H of the second optical pattern 122 may be 5 μm to 100 μm, specifically 10 μm to 30 μm, but is not limited thereto. The pitch of the second optical pattern 122 may be 10 μm to 200 μm, specifically 20 μm to 60 μm, but is not limited thereto.

The second optical pattern 122 may be formed of the same or different composition as the composition forming the first optical pattern 112, or may be formed of the same or different material as the second base layer 121.

The buffer layer 130 is formed between the first optical layer 110 and the second optical layer 120, and can be integrated by bonding the first optical layer 110 and the second optical layer 120 to each other. For example, the buffer layer 130 may be formed on the lower surface of the second optical layer 120. In addition, a part of the upper portion of the first optical pattern 112 is inserted and absorbs pressure or impact applied to the upper portion of the first optical pattern 112 to prevent damage to the first optical pattern 112. I can.

The buffer layer 130 may have a modulus of 1 MPa to 100 MPa, specifically 10 MPa to 50 MPa. Within the above range, the first optical layer 110 and the second optical layer 120 may not be separated when cutting, while having excellent impact resistance and adhesion, and preventing damage to the first optical pattern.

The surface roughness Ra of the buffer layer 130 may be 0.001 μm to 1.0 μm, specifically 0.2 μm to 0.5 μm. Specifically, the surface roughness may be a surface roughness measured from the side of the first optical pattern 112 of the buffer layer 130. Within the above range, since rainbow, mura, and Newton's ring are not visually recognized, there is no uneven screen display, and screen visibility may be excellent.

The buffer layer 130 may be formed of a composition for a buffer layer including a curable resin having excellent transparency and capable of forming a crosslinking bond. For example, the curable resin may be a photocurable resin or a thermosetting resin, and specifically, a urethane resin, an epoxy resin, an epoxy resin-Lewis acid or polyethylol resin, an unsaturated polyester-styrene resin, acrylic acid or methacrylic acid Ester-based resins, etc. can be used, and more specifically, urethane-based (meth)acrylate resins, urethane-based polyol resins, epoxy resins, polyester-based (meth)acrylate resins, non-urethane-based (meth)acrylate resins, or these A combination of can be used.

The composition for the buffer layer may include a urethane-based (meth)acrylate resin. The urethane-based (meth)acrylate resin may be a monofunctional or polyfunctional urethane (meth)acrylate oligomer, specifically 1 or more functional, more specifically 2 to 6 functional urethane (meth)acrylate oligomers, more specifically 2 It may be a functional urethane (meth)acrylate oligomer, and may have a modulus suitable for the buffer layer within the above range. For example, a polycarbonate-based bifunctional urethane acrylate oligomer may be used, but is not limited thereto. The urethane-based (meth)acrylic oligomer may have a weight average molecular weight (Mw) of 500 g/mol to 20,000 g/mol, specifically 2,000 g/mol to 10,000 g/mol, and more specifically 3,000 g/mol to 10,000 g/mol. . The molecular weight may have a modulus suitable for the buffer layer within the above range.

The urethane-based (meth)acrylate resin may be included in an amount of 30% to 80% by weight, specifically 50% to 80% by weight, based on a solid content of the composition for a buffer layer. Within the above range, the impact of the upper portion of the first optical pattern may be buffered, and adhesion may be excellent.

The composition for the buffer layer may include a urethane-based polyol resin. The urethane-based polyol resin may be a bifunctional polyol, and for example, KUB360 manufactured by Kangnam Chemical Co., Ltd. may be used, but the present invention is not limited thereto. The urethane-based polyol resin may have a weight average molecular weight (Mw) of 5,000 g/mol to 30,000 g/mol, specifically 10,000 g/mol to 20,000 g/mol.

The urethane-based polyol resin may be used alone as a curable resin in the composition for the buffer layer, or when used in combination with other curable resins, 0% to 30% by weight, specifically 5% to 20% by weight, based on the solid content of the composition for the buffer layer Can be included. Within the above range, the impact of the upper portion of the first optical pattern may be buffered, and adhesion may be excellent.

The composition for the buffer layer may include an epoxy resin. The epoxy resin may be an epoxy resin, an epoxy resin-Lewis acid resin, and specifically may include a copolymer having at least one bonding structure selected from the group consisting of bisphenol type, novolak type, glycidyl type and alicyclic group. However, it is not limited to these. For example, bisphenol A or F type polymer or modified epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, epoxy resin selling dicyclopentadiene as the main skeleton, dimer acid modified epoxy resin, An epoxy resin or a urethane-modified epoxy resin having propylene glycol as its main skeleton may be exemplified, and it may be a thermosetting resin that does not have an acrylic group.

The epoxy resin may have a weight average molecular weight of 10,000 g/mol to 100,000 g/mol. Within the above range, there may be excellent adhesion, adhesion reliability, and surface irregularities.

The epoxy resin may be included in an amount of 0% to 30% by weight, specifically 5% to 25% by weight based on solid content in the composition for the buffer layer. Within the above range, there may be excellent adhesion, surface irregularities, and adhesion reliability improvement effects.

The composition for the buffer layer may include a polyester-based (meth)acrylate resin. The polyester-based (meth)acrylate resin may be a polyester (meth)acrylate oligomer, for example, a 2-6 functional polyester (meth)acrylate oligomer, and specifically, a 2-3 functional polyester ( A meth)acrylate oligomer may be used, but is not limited thereto. The polyester-based (meth)acrylate resin may have a weight average molecular weight (Mw) of 1,000 g/mol to 10,000 g/mol, specifically 3,000 g/mol to 6,000 g/mol.

The polyester (meth)acrylate resin may be included in an amount of 0% to 30% by weight, specifically 5% to 20% by weight, based on a solid content of the composition for a buffer layer. Within the above range, the impact of the upper portion of the first optical pattern may be buffered, and adhesion may be excellent.

The composition for the buffer layer may include a non-urethane-based (meth)acrylate resin. The non-urethane-based (meth)acrylate resin is a non-urethane-based, which does not contain a urethane group, and may be a non-urethane-based (meth)acrylate-based monomer. It may contain one or more of (meth)acrylate-based monofunctional or polyfunctional monomers, specifically monofunctional or more, specifically bifunctional to 6functional monomers, a linear or branched C1-C20 alkyl group Polyfunctional (meth)acrylate having a (meth)acrylate, a (meth)acrylate having an alkyl group having 1 to 20 carbon atoms having a hydroxy group, a (meth)acrylate having an alicyclic group having 3 to 20 carbon atoms, and a polyhydric alcohol having 3 to 20 carbon atoms ( Meth)acrylate, or a mixture thereof. More specifically, the binder is isobornyl (meth)acrylate, cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate , Ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, tris(2-hydroxyethyl)isocyanuate tri(meth)acrylate , Glycerol tri(meth)acrylate, ethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, hexanediol di(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipenta It may include at least one of erythritol hexa (meth) acrylate and cyclodecane dimethanol di (meth) acrylate, but is not limited thereto.

Specifically, the non-urethane-based (meth)acrylate-based monomer is a trifunctional (meth)acrylate monomer having three (meth)acrylate groups, and is modified with a (meth)acrylic monomer of a polyhydric alcohol having 3 to 20 carbon atoms, and an alkoxy group. It may include at least one of the (meth)acrylic monomers of polyhydric alcohols having 3 to 20 carbon atoms. (Meth)acrylic monomers of polyhydric alcohols having 3 to 20 carbon atoms are specifically trimethylolpropane tri(meth)acrylate, glycerol tri(meth)acrylate, One or more of pentaerythritol tri(meth)acrylate and dipentaerythritol tri(meth)acrylate may be included, but are not limited thereto. Specifically, it may have an alkoxy group having 1 to 5 carbon atoms, for example, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated glyceryl tri(meth)acrylic It may include one or more of a rate (propoxylated glyceryl tri(meth)acrylate), but is not limited thereto.

The non-urethane-based (meth)acrylate resin may be included in an amount of 0% to 35% by weight, specifically 5% to 30% by weight, based on a solid content of the composition for a buffer layer. The adhesive strength may be excellent within the above range.

The buffer layer 130 may include an initiator. The initiator may include a photoinitiator, for example, phosphine oxide, cyclohexylphenylketone, and the like, and these may be included alone or in combination of two or more. The initiator may be included in 1% to 10% by weight, specifically 1% to 5% by weight, based on the solid content of the composition for the buffer layer, in the above range, the composition for the buffer layer can be completely cured and the remaining amount of the initiator remains. It can prevent the transparency of the deterioration.

The composition for the buffer layer may further include a solvent to increase the coatability of the composition for the buffer layer. For example, the solvent may be at least one of methyl ethyl ketone and ethyl acetate.

The composition for the buffer layer may further include conventional additives, for example, a dispersant, an antistatic agent, a surfactant, and the like.

The thickness of the buffer layer 130 may be 5 μm to 50 μm, specifically 8 μm to 30 μm, and more specifically 10 μm to 20 μm. Within the above range, impact resistance and adhesion may be excellent, and the first optical pattern 112 may be prevented from being damaged, and the first optical layer 110 and the second optical layer 120 may not be separated during cutting.

Hereinafter, a composite optical film according to another embodiment of the present invention will be described with reference to FIG. 2. 2 is a schematic diagram showing a cross section of a composite optical film according to another embodiment of the present invention.

The composite optical film according to another embodiment of the present invention is formed on the first optical layer 110 including the first optical pattern 112 and the first optical layer 110, and includes the second optical pattern 122. A second optical layer 120, a buffer layer 130 ′, and an adhesive layer 140 may be included between the first optical layer 110 and the second optical layer 120. It is the same as described for the composite optical film according to an embodiment of the present invention, except that the buffer layer 130 ′ and the adhesive layer 140 are included between the first optical layer 110 and the second optical layer 120.

The buffer layer 130 ′ is formed between the first optical layer 110 and the second optical layer 120, for example, the buffer layer 130 ′ may be formed on the lower surface of the second optical layer 120. . The buffer layer 130 ′ may serve to prevent damage to the first optical pattern 112 by absorbing a pressure or impact applied to the upper portion of the first optical pattern 112.

The buffer layer 130 ′ is formed on a lower surface of the second optical layer 120, an adhesive layer 140 may be formed under the buffer layer 130 ′, and the buffer layer 130 ′ is a first optical pattern 112 The upper part of) can be inserted or not inserted.

The buffer layer 130 ′ may have a modulus of 1 MPa to 100 MPa, specifically 10 MPa to 50 MPa. Within the above range, the first optical layer 110 and the second optical layer 120 may not be separated during cutting while having excellent impact resistance and preventing damage to the first optical pattern.

The thickness of the buffer layer 130 ′ may be 2 μm to 30 μm, specifically 5 μm to 15 μm. Within the above range, impact resistance and adhesion may be excellent, and the first optical pattern 112 may be prevented from being damaged, and the first optical layer 110 and the second optical layer 120 may not be separated during cutting.

The buffer layer 130 ′ may be formed of a composition for a buffer layer including a photocurable resin or a thermosetting resin that is excellent in transparency and capable of forming a crosslinking bond. For example, the photocurable resin or thermosetting resin may be a urethane resin, an epoxy resin, an epoxy resin-Lewis acid or polyethylol resin, an unsaturated polyester-styrene resin, acrylic acid or methacrylic acid ester resin, etc. , Specifically, a urethane-based (meth)acrylate resin, a urethane-based polyol resin, an epoxy resin, a polyester-based (meth)acrylate resin, a non-urethane-based (meth)acrylate resin, or a combination thereof may be used.

Since the composition for the buffer layer is specifically the same as described for the composite optical film of the embodiment of the present invention, description thereof will be omitted.

The adhesive layer 140 is formed between the first optical layer 110 and the second optical layer 120, for example, the adhesive layer 140 may be formed on the lower surface of the buffer layer 130 ′.

The adhesive layer 140 is formed between the first optical layer 110 and the second optical layer 120, and can be integrated by bonding the first optical layer 110 and the second optical layer 120 to each other. For example, the adhesive layer 140 may be formed on the lower surface of the second optical layer 120. In addition, the adhesive layer 140 inserts a part of the upper portion of the first optical pattern 112 together with the buffer layer 130 ′, and absorbs the pressure or impact applied to the upper portion of the first optical pattern 112 to form the first optical pattern. (112) can play a role in preventing damage.

The surface roughness Ra of the adhesive layer 140 may be 0.001 μm to 1.0 μm, specifically 0.2 μm to 0.5 μm. Specifically, the surface roughness may be a surface roughness measured on the lower surface of the adhesive layer 140. Within the above range, since rainbow, mura, and Newton's ring are not visually recognized, there is no uneven screen display, and screen visibility may be excellent.

The thickness of the adhesive layer 140 may be 0.1 µm to 5 µm, specifically 0.5 µm to 3 µm, and has excellent impact resistance and adhesion within the above range, and has an effect of preventing damage to the first optical pattern 112 and at the same time. When the first optical layer 110 and the second optical layer 120 are cut, they may not be separated.

The adhesive layer 140 may be formed of a composition for an adhesive layer including a photocurable resin or a thermosetting resin that is excellent in transparency and capable of forming a crosslinking bond. For example, the photocurable resin or thermosetting resin may be a urethane resin, an epoxy resin, an epoxy resin-Lewis acid or polyethylol resin, an unsaturated polyester-styrene resin, acrylic acid or methacrylic acid ester resin, etc. , Specifically, a urethane-based (meth)acrylate resin, a urethane-based polyol resin, an epoxy resin, a polyester-based (meth)acrylate resin, a non-urethane-based (meth)acrylate resin, or a combination thereof may be used.

Specifically, since the composition for the adhesive layer is the same as described for the composition for the buffer layer forming the buffer layer 130 ′, the description is omitted. The curable resin forming the buffer layer 130 ′ may be, for example, a urethane-based polyol resin, but is not limited thereto. The curable resin forming the buffer layer 130 ′ and the adhesive layer 140 may be the same or different from each other.

The thickness of the adhesive layer 140 may be thinner than that of the buffer layer 130 ′, and a thickness ratio of the adhesive layer 140 and the buffer layer 130 ′ may be 1:1 to 1:10. Good impact resistance can be obtained within the above range.

When the adhesive layer 140 and the buffer layer 130 ′ are stacked, the modulus measured on the surface of the adhesive layer may be 1 MPa to 100 MPa, specifically 10 MPa to 30 MPa. Within the above range, the first optical layer 110 and the second optical layer 120 may not be separated when cutting, while having excellent impact resistance and adhesion, and preventing damage to the first optical pattern.

In this embodiment, in the first optical pattern 112, the convex portions of the pattern upper portion may be partially inserted into the adhesive layer 140 or the adhesive layer 140 and the buffer layer 130 ′. The depth at which the first optical pattern 112 is inserted into the adhesive layer 140 or the adhesive layer 140 and the buffer layer 130 ′ is greater than 0 and 20% or less of the height H of the first optical pattern 112 , Specifically, it may be 5% to 10%. Within the above range, the first optical layer 110 and the second optical layer 120 are not separated, and luminance deterioration can be prevented. The depth at which the first optical pattern 112 is inserted into the adhesive layer 140 or the adhesive layer 140 and the buffer layer 130 ′ is from the lower surface of the second base layer 121 of the second optical layer 120 to be described later. The vertical length to the top vertex of the first optical pattern 112 may be 3 μm to 10 μm, but is not limited thereto.

Hereinafter, a method of manufacturing a composite optical film according to an embodiment of the present invention will be described.

A method of manufacturing a composite optical film according to an embodiment of the present invention provides a first optical layer and a second optical layer, applies a composition for a buffer layer on one surface of the second optical layer, and first cures the buffer layer line- It may include forming a buffer layer by forming a cured layer, contacting the first optical layer with the pre-curing layer for the buffer layer, and second curing the pre-curing layer for the buffer layer.

The first optical layer, the second optical layer, and the buffer layer are the same as described for the composite optical film according to the embodiments of the present invention.

Each of the first optical layer and the second optical layer can be manufactured by a conventional method. Specifically, the first optical layer includes a first optical pattern, a composition for forming a first optical pattern is coated on one surface of the first substrate layer, and a pattern on the coating is performed using a pattern roll in which the first optical pattern is engraved. It can be prepared by applying and curing. As the second optical layer, the second base layer may be used alone, or a composition for forming a second optical pattern is coated on the other surface of the second base layer, and the pattern is applied to the coating by using a pattern roll in which the second optical pattern is engraved. And can be prepared by curing.

A composition for a buffer layer is applied to one side of the second optical layer, specifically one side of the second base layer. The application method is not particularly limited, and may be, for example, die coating, roll coating, spin coating, bar coating, or the like.

After the composition for the buffer layer is applied, first curing is performed to form a pre-cured layer for the buffer layer. Through the first curing, the composition for the buffer layer can be prevented from flowing down when the first optical pattern penetrates, thereby preventing a decrease in luminance. The first curing may include exposure with ultraviolet rays 1mJ/cm2 to 100mJ/cm2 when the composition for the buffer layer contains a photocurable resin, and when the composition for the buffer layer contains a thermosetting resin, 24 at 35-50°C It may include heat curing for hours to 72 hours, but is not limited thereto.

The first optical layer is brought into contact with the pre-curing layer for the buffer layer. Specifically, by penetrating the first optical pattern into the pre-curing layer for the buffer layer, the first optical layer and the second optical layer may be integrated due to the second curing.

The buffer layer is formed by second curing the pre-curing layer for the buffer layer. The pre-curing layer for the buffer layer may be second cured, so that the first optical layer and the second optical layer may be integrated through the buffer layer. When the composition for the buffer layer contains a photocurable resin, the second curing may include exposure with ultraviolet rays of 200mJ/cm2 to 500mJ/cm2, and when the composition for the buffer layer contains a thermosetting resin, it is 24 at 35-50°C. It may include heat curing for hours to 72 hours, but is not limited thereto.

Hereinafter, a method of manufacturing a composite optical film according to another embodiment of the present invention will be described.

In the method of manufacturing a composite optical film according to another embodiment of the present invention, a first optical layer and a second optical layer are provided, a composition for a buffer layer is applied to one surface of the second optical layer, and cured to form a buffer layer. The adhesive layer is applied by applying a composition for an adhesive layer on one side and curing the first to form a pre-curing layer for the adhesive layer, contacting the first optical layer with the pre-curing layer for the adhesive layer, and second curing the pre-curing layer for the adhesive layer. It may include forming. It is the same as described for the method of manufacturing a composite optical film according to an embodiment of the present invention, except for forming a buffer layer and forming an adhesive layer on one side of the buffer layer.

A composition for a buffer layer is applied to one side of the second optical layer, specifically one side of the second base layer. The application method is not particularly limited, and may be, for example, die coating, roll coating, spin coating, bar coating, or the like.

After the composition for a buffer layer is applied, it is cured to form a buffer layer. When the composition for the buffer layer contains a photocurable resin, it may include exposure with ultraviolet rays of 200mJ/cm2 to 500mJ/cm2, and when the composition for the buffer layer contains a thermosetting resin, at 35-50° C. for 24 hours to 72 hours It may include thermal curing during, but is not limited thereto. It may further include drying before curing after applying the composition for the buffer layer.

The adhesive layer composition is applied to one side of the buffer layer. The application method is not particularly limited, and may be, for example, die coating, roll coating, spin coating, bar coating, or the like.

After the composition for an adhesive layer is applied, it is first cured to form a pre-cured layer for an adhesive layer. Through the first curing, the composition for the adhesive layer can be prevented from flowing down when the first optical pattern penetrates, thereby preventing a decrease in luminance. The first curing may include exposure with ultraviolet rays 1mJ/cm2 to 100mJ/cm2 when the composition for the adhesive layer contains a photocurable resin, and when the composition for the adhesive layer contains a thermosetting resin, 24 at 35-50°C It may include heat curing for hours to 72 hours, but is not limited thereto.

The first optical layer is brought into contact with the pre-curing layer for the adhesive layer. Specifically, by penetrating the first optical pattern into the pre-curing layer for the adhesive layer, the first optical layer and the second optical layer may be integrated due to the second curing.

The adhesive layer is formed by second curing the pre-curing layer for the adhesive layer. The first optical layer and the second optical layer may be integrated by second curing the pre-curing layer for the adhesive layer. The second curing may include exposure with ultraviolet rays of 200mJ/cm2 to 500mJ/cm2 when the composition for the adhesive layer contains a photocurable resin, and when the composition for the adhesive layer contains a thermosetting resin, it is 24 at 35-50°C. It may include heat curing for hours to 72 hours, but is not limited thereto.

Hereinafter, a method of manufacturing a composite optical film according to another embodiment of the present invention will be described.

The method of manufacturing a composite optical film according to another embodiment of the present invention provides a first optical layer and a second optical layer, applies a composition for a buffer layer on one surface of the second optical layer, and applies a surface roughness (Ra) to the composition for a buffer layer. ) A pattern of 0.001㎛ to 1.0㎛ is transferred and first cured to form a pre-curing layer for the buffer layer, contacting the first optical layer with the pre-curing layer for the buffer layer, and second curing the pre-curing layer for the buffer layer To form a buffer layer. After applying the composition for the buffer layer on one side of the second optical layer, except for transferring the pattern having a surface roughness (Ra) of 0.001㎛ to 1.0㎛, with respect to the manufacturing method of the composite optical film according to an embodiment of the present invention Same as described. Therefore, only the step of transferring the pattern will be described below.

After the composition for a buffer layer is applied to one surface of the second optical layer, a pattern having a surface roughness (Ra) of 0.001 μm to 1.0 μm is transferred to the buffer layer composition.

The pattern may be transferred on the composition for a buffer layer using a transfer film having a surface roughness of 0.001 μm to 1.0 μm, or may be transferred by a sand blasting method. The transfer film has a predetermined surface roughness on the surface and transfers the pattern to the composition for a buffer layer, and the surface roughness becomes 0.2 μm to 1.0 μm, so that a buffer layer having a surface roughness of 0.001 μm to 1.0 μm after the second curing can be implemented. Specifically, the surface roughness of the transfer film may be 0.001 μm to 1.0 μm.

After the pattern is transferred, first curing may be performed to form a pre-cured layer for the buffer layer, and the applied buffer layer may be dried before the pattern transfer.

When a transfer film is used during pattern transfer, the transfer film may be placed on the composition for a buffer layer and the composition for a buffer layer may be first cured. As a result, the composition for the buffer layer can be first cured even with a low UV radiation amount by maintaining a closed state blocked from oxygen and/or moisture. In addition, by using the transfer film, it is possible to impart haze to the buffer layer without introducing inorganic particles into the buffer layer, thereby suppressing the occurrence of rainbow and/or mura. In addition, by performing the second curing after the first curing, a wicking phenomenon due to penetration of the first optical pattern can be suppressed to prevent a decrease in luminance.

The transfer film can be produced using a commercially available product or a metal roll using a sand blasting method. In order to facilitate separation after the first curing, the transfer film may be subjected to a release treatment with a fluorine-based or silicone-based material on a surface in contact with the composition for a buffer layer.

The method of manufacturing a composite optical film according to another embodiment of the present invention provides a first optical layer and a second optical layer, applies a composition for a buffer layer on one surface of the second optical layer, and cures to form a buffer layer, and a buffer layer A composition for an adhesive layer was applied to one side of the adhesive layer, and a pattern having a surface roughness (Ra) of 0.001 μm to 1.0 μm was transferred to the adhesive layer composition and first cured to form a pre-cured layer for the adhesive layer, and then on the pre-cured layer for the adhesive layer. It may include forming an adhesive layer by contacting the first optical layer and second curing the pre-curing layer for the adhesive layer. The same as described for the method of manufacturing a composite optical film according to another embodiment of the present invention, except for transferring a pattern having a surface roughness (Ra) of 0.001 μm to 1.0 μm after applying the adhesive layer composition to one side of the buffer layer. Do. The step of transferring the pattern may be performed in the same manner as the step of transferring the pattern to the above-described composition for a buffer layer, except for transferring the pattern after applying the composition for an adhesive layer to one side of the buffer layer instead of one side of the second optical layer.

The optical display device of the present invention may include, but is not limited to, the composite optical film of the embodiments of the present invention, and may be a liquid crystal display device, an organic light emitting display device, etc. In the liquid crystal display device, the light source is an LED lamp or a CCFL May be included.

Referring to FIG. 3, a liquid crystal display device according to an embodiment of the present invention will be described. 3 is a perspective view of a liquid crystal display according to an exemplary embodiment of the present invention.

The liquid crystal display 300 according to the present embodiment includes a light source 310, a light guide plate 320 for guiding light emitted from the light source 310, a reflective sheet 350 disposed under the light guide plate 320, and a light guide plate. 320, a diffusion sheet 330 disposed on the top of the diffusion sheet 330 and a composite optical film 340 disposed on the diffusion sheet 330, and the composite optical film 340 is a composite optical film of the embodiments of the present invention. Can include.

A light source cover 31a may be disposed outside the light source 310 of the backlight unit. In addition, although not shown here, a liquid crystal display panel and an antireflection layer are sequentially stacked on the liquid crystal display device 300 to constitute a liquid crystal display device.

The light source 310 generates light, and various light sources such as a line light source lamp or a surface light source lamp, CCFL or LED may be used.

The light guide plate 320 guides the light generated from the light source 310 to the diffusion sheet 330, and may be omitted when a direct light source is used.

The reflective sheet 350 serves to reflect light generated from the light source 310 and supply it in the direction of the diffusion sheet 330.

The diffusion sheet 330 diffuses and scatters light incident through the light guide plate 320 and supplies it to the composite optical film 340.

The composite optical film 340 refracts light incident through the diffusion sheet 330 and condenses the light on the plane of the liquid crystal display panel (not shown). The composite optical film 340 is modified in various design values such as the shape of the condensing unit and the angle of the inclined surface of the condensing unit according to various design goals such as high light condensing efficiency, wide viewing angle, prevention of moiré phenomenon, and prevention of optical wet out with other films. And combinations are possible and are being applied commercially.

Hereinafter, the configuration and operation of the present invention will be described in more detail through preferred embodiments of the present invention. However, the following examples are for aiding understanding of the present invention, and the scope of the present invention is not limited to the following examples.

Components used in Examples and Comparative Examples are as follows.

(A) Curable resin:

(a1) Urethane diacrylate oligomer (CN965, Sartomer, bifunctional)

(a2) Urethane diacrylate oligomer (CN981, Sartomer, bifunctional)

(a3) Urethane-based acrylate oligomer (PSU1129, Soltech, bifunctional)

(a4) Urethane-based polyol resin (KUB360, Gangnam Chemical, bifunctional)

(a5) Epoxy acrylate oligomer (CN120, Sartomer, bifunctional, molecular weight 1,000g/mol)

(a6) Epoxy resin (YP50, Kukdo Chemical, molecular weight 55,000g/mol)

(a7) ethoxylated trifunctional acrylate monomer (SR502, Sartomer)

(a8) trifunctional acrylate monomer (SR351, Sartomer)

(B) initiator:

(b1) Irgacure184 (Ciba Special Chemical)

(b2) CL-100 (trifunctional isocyanate, Gangnam Chemical)

(C) Solvent:

(c1) methyl ethyl ketone (MEK, Samjeon Pure Chemical)

(c2) distilled water

Preparation Example 1: Composition for the first buffer layer

As a curable resin, 21 parts by weight of urethane diacrylate oligomer (CN965, Sartomer) and 8.10 parts by weight of ethoxylated trifunctional acrylate monomer (SR502, Sartomer) were mixed and stirred for 10 minutes, and the initiator, Irgacure184 ( Ciba Special Chemical) was added 0.90 parts by weight and stirred for 10 minutes, and 70.0 parts by weight of methyl ethyl ketone (MEK, Samjeon Pure Chemical) was added and stirred for 10 minutes, and then degassed for 10 minutes to obtain the composition for buffer layer of Preparation Example 1. Was prepared.

Preparation Examples 2 to 6: Composition for first buffer layer

Except for using the (A) curable resin, (B) initiator, and (C) solvent in the components and contents shown in Table 1 below, compositions for buffer layers of Preparation Examples 2 to 6 were prepared in the same manner as in Preparation Example 1.

Preparation Example 7: Composition for adhesive layer

To 37.5 parts by weight of a urethane-based polyol resin (KUB360, Gangnam Chemical, Bifunctional) 7.50 parts by weight of CL-100 (Gangnam Chemical) as an initiator was added, stirred for 10 minutes, and 55.0 parts by weight of methyl ethyl ketone (MEK, Samjeon Pure Chemical) as a solvent was added. Then, the mixture was stirred for 10 minutes, and then degassed for 10 minutes to prepare a composition for an adhesive layer.

Preparation Example 8: Preparation of the first optical layer

Uvicx581CI (Fluorene-based high-refractive resin, RI: 1.581) is coated on one side of the PET base film (thickness 50µm), which is the first base layer, and has a cross-sectional triangular shape with the same height of 25µm, a pitch of 50µm, and an apex angle of 90°. A first optical layer was prepared by applying the pattern to the coating material using a pattern roll having a prism pattern engraved thereon, and curing it by exposure.

Preparation Example 9: Preparation of the second optical layer

Uvicx581CI (Fluorene-based high refractive resin, RI: 1.581) is coated on one side of the PET base film (thickness 50µm), which is the second base layer, and has a cross-sectional triangular shape with the same height of 25µm, a pitch of 50µm, and an apex angle of 90°. A second optical layer was manufactured by forming a second optical pattern using a pattern roll in which the prism pattern was engraved.

(Unit: parts by weight) Manufacturing Example 1 Manufacturing Example 2 Manufacturing Example 3 Manufacturing Example 4 Manufacturing Example 5 Manufacturing Example 6 (A) (a1) 21 0 20.24 0 0 0 (a2) 0 21 0 0 0 0 (a3) 0 0 0 0 15 0 (a4) 0 0 0 35.57 0 0 (a5) 0 0 0 0 0 21 (a6) 0 0 0 0 6 0 (a7) 8.1 8.1 7.81 0 0 0 (a8) 0 0 0 0 7.5 8.1 (B) (b1) 0.9 0.9 0.87 0 1.5 0.9 (b2) 0 0 1.44 8.89 0 0 (C) (c1) 70 70 69.06 54.83 70 70 (c2) 0 0 0.58 0.71 0 0 Total 100 100 100 100 100 100

Example 1

After coating the composition for the buffer layer of Preparation Example 1 on the other side of the second base layer of the second optical layer prepared in Preparation Example 9 with a Mayer bar, drying it in an oven at 80° C. for 2 minutes, and exposed to ultraviolet rays at 300 mJ/㎠ to a thickness of 10 μm A buffer layer of was prepared, and the adhesive layer composition of Preparation Example 7 was applied to a thickness of 2 μm on the buffer layer, and dried in an oven at 80° C. for 2 minutes to form an adhesive layer.

The first optical layer and the first optical layer so that the prism mountain direction of the prism pattern of the first optical layer prepared in Preparation Example 8 is orthogonal to the second optical layer, and the upper portion of the prism pattern of the first optical layer is inserted into the adhesive layer. The two optical layers were laminated and heat-aged at 40° C. for 2 days to prepare a composite optical film.

Example 2

A composite optical film was manufactured in the same manner as in Example 1, except that the composition for the buffer layer of Preparation Example 2 was used instead of the composition for the buffer layer of Preparation Example 1.

Example 3

A composite optical film was manufactured in the same manner as in Example 1, except that the composition for the buffer layer of Preparation Example 3 was used instead of the composition for the buffer layer of Preparation Example 1.

Example 4

After coating the composition for the buffer layer of Preparation Example 4 on the other side of the second base layer of the second optical layer prepared in Preparation Example 9 with a Mayer bar, it was dried in an oven at 80° C. for 2 minutes, and a buffer layer having a thickness of 10 μm was prepared, and silicone After laminating the coated release film (MRF38, Mitsubishi Plastics), it was heat-aged at 40°C for 2 days. Then, after removing the release film, the adhesive layer composition of Preparation Example 7 was applied to a thickness of 2 μm on the coated buffer layer, and dried in an oven at 80° C. for 2 minutes to form an adhesive layer.

The first optical layer and the first optical layer so that the prism mountain direction of the prism pattern of the first optical layer prepared in Preparation Example 8 is orthogonal to the second optical layer, and the upper portion of the prism pattern of the first optical layer is inserted into the adhesive layer. The two optical layers were laminated and heat-aged at 40° C. for 2 days to prepare a composite optical film.

Example 5

After coating the composition for the buffer layer of Preparation Example 5 on the other side of the second base layer of the second optical layer prepared in Preparation Example 9 with a Mayer bar, it was dried in an oven at 80° C. for 2 minutes, and a black light lamp (FL20SBL (20W), Sankyo Denki) was exposed to ultraviolet rays of 10mJ/cm2 and first cured to prepare a buffer layer having a thickness of 10 μm.

The first optical layer and the first optical layer so that the prism mountain direction of the prism pattern of the first optical layer prepared in Preparation Example 8 is orthogonal to the second optical layer, and the upper portion of the prism pattern of the first optical layer is inserted into the buffer layer. The two optical layers were laminated, and the laminated sheet was prepared by second curing by UV exposure of 500mJ/cm2 with a metal UV lamp (D bulb, Fusion).

Example 6

After coating the composition for the buffer layer of Preparation Example 1 on the other side of the second base layer of the second optical layer prepared in Preparation Example 9 with a Mayer bar, drying it in an oven at 80° C. for 2 minutes, and exposed to ultraviolet rays at 300 mJ/㎠ to a thickness of 10 μm A buffer layer of was prepared, and the adhesive layer composition of Preparation Example 7 was applied on the buffer layer to a thickness of 2 μm to form an adhesive layer. After drying in an oven at 80° C. for 2 minutes, a transfer film having a pattern having a surface roughness of 0.5 μm was laminated to engrave a random pattern.

While removing the transfer film so that the prism mountain direction of the prism pattern of the first optical layer prepared in Preparation Example 8 is orthogonal to the second optical layer, the upper portion of the prism pattern of the first optical layer is inserted into the adhesive layer. The first optical layer and the second optical layer were laminated and heat-aged at 40° C. for 2 days to prepare a composite optical film.

Example 7

After coating the composition for the buffer layer of Preparation Example 5 on the other side of the second base layer of the second optical layer prepared in Preparation Example 9 with a Mayer bar, drying it in an oven at 80° C. for 2 minutes, and exposing the film to Black Light at 50 mJ/cm 2 A buffer layer having a thickness of 10 μm was prepared by curing 1, and a transfer film having a pattern having a surface roughness of 0.5 μm was laminated.

While removing the pattern transfer film so that the direction of the prism mountain of the prism pattern of the first optical layer prepared in Preparation Example 8 is orthogonal to the second optical layer, the upper portion of the prism pattern of the first optical layer is inserted into the buffer layer. The first optical layer and the second optical layer were laminated, and then subjected to ultraviolet light exposure of 300mJ/cm2 with a metal UV lamp (D-bulb, Fusion) to second cure to prepare a laminated sheet.

Comparative Example 1

A composite optical film was manufactured in the same manner as in Example 1, except that the composition for the buffer layer of Preparation Example 6 was used instead of the composition for the buffer layer of Preparation Example 1.

Comparative Example 2

The adhesive layer composition of Preparation Example 7 was applied to the other surface of the second base layer of the second optical layer prepared in Preparation Example 9 to a thickness of 2 μm and dried in an oven at 80° C. for 2 minutes to prepare an adhesive layer.

The first optical layer and the first optical layer so that the prism mountain direction of the prism pattern of the first optical layer prepared in Preparation Example 9 is orthogonal to the second optical layer, and the upper portion of the prism pattern of the first optical layer is inserted into the adhesive layer. The two optical layers were laminated and heat-aged at 40° C. for 2 days to prepare a composite optical film.

The following physical properties were evaluated for the composite optical films of Examples and Comparative Examples.

(1) Modulus (MPa): For the adhesive layer (Examples 1 to 4 and 6, Comparative Examples 1 to 2) or the buffer layer (Examples 5 and 7) before lamination of the first optical layer of the composite optical films of Examples and Comparative Examples Using an indentation equipment (FISCHERSCOPE, HM2000, tip: vickers vv516) while maintaining a force of 80mN for 5 seconds, after randomly selecting a measurement location with a micro indenter, 5 points were measured at 25°C and the average value was calculated.

(2) Peeling strength (gf/30mm): The laminated composite optical film of the first optical layer and the second optical layer of Examples and Comparative Examples was measured for a sample having a width of 15 cm × 30 mm. Using a universal testing machine (H5KT, Tinius Olsen) at a rate of 10 mm/sec, the buffer layer of the second optical layer (Examples 5 and 7) or the buffer layer and the adhesive layer (Examples 1 to 4 and 6, Comparative Examples 1 to 2) The 90° peel force was measured.

(3) Impact resistance (cm): The minimum height at which peeling of the laminated surface due to free-fall impact starts to occur by dropping a ball having a weight of 36 g on the composite optical films of Examples and Comparative Examples from 0 to 50 cm ( cm) was measured to evaluate the impact resistance. The higher the value, the better the impact resistance.

Example Comparative example One 2 3 4 5 6 7 One 2 Modulus (Mpa) 45 73 43 68 85 45 85 581 455 Adhesion (gf/30mm) 135 154 145 149 78 135 75 152 143 Impact resistance (cm) 15 15 15 15 15 15 15 5 5

From the results of Table 1, it can be seen that the modulus of the composite optical film of the embodiment is within the range of 1 MPa to 100 MPa, and a composite optical film having excellent impact resistance can be provided. On the other hand, in the case of the comparative example, it can be seen that the modulus is out of the scope of the present invention and the impact resistance is poor.

Claims (15)

A first optical layer including a first optical pattern,
A second optical layer formed on the first optical layer and including a second base layer and a second optical pattern formed on the second base layer, and
A buffer layer formed between the first optical layer and the second optical layer,
The modulus of the buffer layer is 1 MPa to 100 MPa,
The first optical pattern is formed of a composition containing an ultraviolet curable unsaturated compound or a thermoplastic resin,
The second base layer is formed of a thermoplastic resin, the composite optical film. The method of claim 1,
The first optical pattern is a composite optical film of a prism pattern. The method of claim 1,
The second optical pattern is a composite optical film including a prism having a polygonal cross section, a microlens pattern, a lenticular lens pattern, an emboss pattern, or a combination thereof. The method of claim 1,
The first optical pattern is a composite optical film inserted into the buffer layer. The method of claim 4,
A composite optical film having a depth at which the first optical pattern is inserted into the buffer layer is greater than 0 and 20% or less of the height of the first optical pattern. The method of claim 4,
The depth at which the first optical pattern is inserted into the buffer layer is 3 μm to 10 μm in a vertical length from a lower surface of the second optical layer to an upper vertex of the first optical pattern. The method of claim 1,
A composite optical film having a thickness of the buffer layer of 5 μm to 50 μm. The method of claim 1,
The buffer layer is a composite optical film comprising a urethane-based (meth)acrylate resin, a urethane-based polyol resin, an epoxy resin, a polyester-based (meth)acrylate resin, a non-urethane-based (meth)acrylate resin, or a combination thereof. The method of claim 1,
A composite optical film having a surface roughness (Ra) of 0.001 μm to 1.0 μm of the buffer layer. The method of claim 1,
A composite optical film further comprising an adhesive layer formed between the buffer layer and the second optical layer. The method of claim 10,
A composite optical film having a modulus of 1 MPa to 100 MPa measured by a micro indenter using an indentation equipment (FISCHERSCOPE, HM2000, tip: vickers vv516) while maintaining the adhesive layer side with a force of 80 mN for 5 seconds. The method of claim 10,
The thickness of the buffer layer is thicker than the thickness of the adhesive layer composite optical film. The method of claim 10,
The adhesive layer has a thickness of 0.1 μm to 5 μm, and the buffer layer has a thickness of 2 μm to 30 μm. The method of claim 10,
The first optical pattern is a composite optical film inserted into the adhesive layer or the adhesive layer and the buffer layer. A display device comprising the composite optical film of any one of claims 1 to 14.

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