KR20160053276A - Optical sheet and optical display apparatus comprising the same - Google Patents

Abstract

The present invention relates to an optical sheet and an optical display device including the same. The optical sheet comprises: a base film; and an optical pattern layer formed on one surface of the base film. Therefore, the optical sheet can increase brightness with a high refraction rate when a liquid crystal display device is used.

Description

TECHNICAL FIELD [0001] The present invention relates to an optical sheet and an optical display device including the optical sheet.

The present invention relates to an optical sheet and an optical display device including the optical sheet.

A liquid crystal display device includes a base film and an optical sheet including an optical pattern formed on the base film. A light guide plate may be disposed under the optical sheet, or another optical sheet may be disposed between the optical sheet and the light guide plate. The optical sheet refracts light emitted from the light guide plate and emits the light. In order to increase the brightness of the liquid crystal display device, the refractive index of the optical sheet must be increased. However, there has been a limit in increasing the refractive index of the optical sheet when the high refractive index monomer is used. Further, even when the refractive index of the optical sheet is increased, yellowing occurs in the optical sheet, and adhesion and the like are not good.

Further, a protective sheet or another optical sheet may be further formed on the optical sheet. The optical pattern can be influenced by the contact of the optical pattern layer of the optical sheet with the protective sheet or the like and the brightness of the liquid crystal display device can be lowered so that it is necessary to improve the scratch resistance in addition to the refractive index.

The background art of the present invention is disclosed in Korean Patent Publication No. 2013-0074115.

An object of the present invention is to provide an optical sheet having a high refractive index and capable of increasing brightness when used in a liquid crystal display, and an optical display device including the same.

Another object of the present invention is to provide an optical sheet excellent in restitution force, scratch resistance and impact resistance, and an optical display device including the optical sheet.

The above and other objects of the present invention can be achieved by the present invention described below.

One aspect of the present invention relates to an optical sheet.

According to one embodiment, the optical sheet includes a base film and an optical pattern layer formed on one surface of the base film, wherein the optical pattern layer includes a unit derived from a (meth) acrylic compound represented by the following formula Wherein the optical pattern layer is formed by pressing the optical pattern layer with an indenter under the conditions [i] to iii) below, and when the pressing force of the optical pattern layer with the indenter is 30 mN, Hmax, which is the depth at which the light enters the optical pattern layer, is 3 [mu] m to 15 [mu] m:

[Chemical Formula 1]

이고, 여기서 X₁ 및 X₂는 각각 독립적으로 *-O-* 또는 *-S-*이고, Q는 탄소수 1 내지 10의 알킬렌이고, Y는 수소 또는 메틸기이고, n은 1 내지 50의 정수이고, *는 결합부위를 나타낸다)(Wherein R ₁ , R ₂ and R ₃ are each independently

, Wherein X ₁ and X ₂ are each independently * -O- * or * -S- *, Q is alkylene having 1 to 10 carbon atoms, Y is hydrogen or a methyl group, and n is an integer of 1 to 50 And * represents a binding site)

[Measuring conditions]

i) Initial force at which the indenter presses the optical pattern layer: 0 mN

ii) the rate of increase per second of the force the indenter presses the optical pattern layer: 0.6 mN / s

iii) Direction in which the indenter presses the optical pattern layer: direction perpendicular to the optical pattern layer

iv) The indenter uses a bar having a circular cross section having a diameter of 50 μm.

According to another embodiment, the optical pattern layer may have a Δh of 1.3 μm or less in the following formula (1).

<Formula 1>

H = h2 - h1

(Where h1 is the pressing force of the optical pattern layer with the indenter under the conditions of i) to iv), when the pressing force of the indenter on the optical pattern layer before reaching hmax is 5 mN, When the optical pattern layer is pressed by the indenter under the conditions of i) to iv), the pressing force of the indenter on the optical pattern layer after reaching the hmax is 5 mN The depth at which the indenter enters the optical pattern layer).

According to another embodiment, the optical pattern layer is formed of a composition for forming an optical pattern containing 25% by weight to 75% by weight of a (meth) acrylic compound represented by the general formula (1), and Δh is 0 μm to 0.9 μm .

According to another embodiment, the optical pattern layer is formed of a composition for forming an optical pattern containing 5% by weight to 40% by weight of a (meth) acrylic compound represented by the general formula (1), and Δh is from 0.5 μm to 1.3 μm .

According to another embodiment, the refractive index of the optical pattern layer may be 1.50 to 1.70.

According to another embodiment of the present invention, the optical pattern layer is formed on the optical pattern layer in such a manner that an ag pole (AG Pol) and a weight having a weight between 0 and 100 g are sequentially placed on the optical pattern layer, The weight of the first weight at which the optical pattern layer begins to be damaged after the reciprocating motion can be 15 g or more.

According to another embodiment, the optical pattern layer may be an ethylene group.

According to another embodiment, the optical sheet may further include a coating layer on the other surface of the base film.

Another aspect of the invention relates to a composite optical sheet.

According to one embodiment, the composite optical sheet includes a first optical sheet and a second optical sheet formed on the first optical sheet, and at least one of the first optical sheet and the second optical sheet includes the optical Sheet.

According to another embodiment, the first optical sheet includes an optical pattern layer formed of a composition for forming an optical pattern containing 5% by weight to 40% by weight of a (meth) acrylic compound represented by the following general formula (1) Lt; / RTI &gt; to &lt; RTI ID = 0.0 &gt;

[Chemical Formula 1]

이고, 여기서 X₁ 및 X₂는 각각 독립적으로 *-O-* 또는 *-S-*이고, Q는 탄소수 1 내지 10의 알킬렌이고, Y는 수소 또는 메틸기이고, n은 1 내지 50의 정수이고, *는 결합부위를 나타낸다).(Wherein R ₁ , R ₂ and R ₃ are each independently

, Wherein X ₁ and X ₂ are each independently * -O- * or * -S- *, Q is alkylene having 1 to 10 carbon atoms, Y is hydrogen or a methyl group, and n is an integer of 1 to 50 , And * indicates a binding site).

According to another embodiment, the first optical sheet may comprise 35 wt% to 60 wt% of a monomer having a refractive index of 1.62 or more, 5 wt% to 40 wt% of a (meth) acrylic compound represented by the formula (1) % To 50% by weight of an optical pattern layer formed of a composition for forming an optical pattern.

According to another embodiment, the second optical sheet includes an optical pattern layer formed of a composition for forming an optical pattern containing 25 wt% to 75 wt% of a (meth) acrylic compound represented by the following general formula (1) Can be from 0 [mu] m to 0.9 [mu] m:

[Chemical Formula 1]

이고, 여기서 X₁ 및 X₂는 각각 독립적으로 *-O-* 또는 *-S-*이고, Q는 탄소수 1 내지 10의 알킬렌이고, Y는 수소 또는 메틸기이고, n은 1 내지 50의 정수이고, *는 결합부위를 나타낸다).(Wherein R ₁ , R ₂ and R ₃ are each independently

, Wherein X ₁ and X ₂ are each independently * -O- * or * -S- *, Q is alkylene having 1 to 10 carbon atoms, Y is hydrogen or a methyl group, and n is an integer of 1 to 50 , And * indicates a binding site).

According to another embodiment, the first optical sheet comprises 15 to 40% by weight of a monomer having a refractive index of 1.62 or more, 25 to 75% by weight of a (meth) acrylic compound represented by the formula (1) % To 40% by weight of an optical pattern layer formed of a composition for forming an optical pattern.

Another aspect of the present invention relates to an optical display device.

According to one embodiment, the optical display device may include the optical sheet or the composite optical sheet.

The present invention has the effect of providing an optical sheet having a high refractive index and capable of raising the brightness of a liquid crystal display device and having excellent restoring force, scratch resistance and impact resistance, and an optical display device including the optical sheet.

1 is a perspective view of an optical sheet according to one embodiment.
Fig. 2 is a cross-sectional view taken along line XY in Fig. 1. Fig.
3 is a perspective view of an optical sheet according to another embodiment.
4 is a perspective view of a composite optical sheet according to one embodiment.
5 is a perspective view of an optical display device according to one embodiment.
6 is a conceptual diagram of hmax and? H.

Embodiments of the present application will now be described in more detail with reference to the accompanying drawings. However, the techniques disclosed in this application are not limited to the embodiments described herein but may be embodied in other forms. It should be understood, however, that the embodiments disclosed herein are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the width, thickness, and the like of the components are enlarged in order to clearly illustrate the components of each device. Like numbers refer to like elements throughout the several views.

The terms "upper" and "lower" in this specification are defined with reference to the drawings, wherein "upper" may be changed to "lower", "lower" What is referred to as &quot; on &quot; may include not only superposition, but also intervening other structures in the middle. On the other hand, what is referred to as &quot; directly on &quot; or &quot; directly above &quot;

As used herein, &quot; (meth) acrylic &quot; means acrylic and / or methacrylic.

Hereinafter, an optical sheet according to an embodiment of the present invention will be described with reference to Fig. FIG. 1 is a perspective view of an optical sheet according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line X-Y in FIG.

1, an optical sheet 100 according to an embodiment of the present invention includes a base film 110 and an optical pattern layer 120 formed on one surface of the base film 110. The optical pattern layer 120 (Meth) acrylic compound represented by the following formula (1), and the optical pattern layer (120) has a maximum indentation depth (hmax) of 3 탆 to 15 탆:

[Chemical Formula 1]

이고, 여기서 X₁ 및 X₂는 각각 독립적으로 *-O-* 또는 *-S-*이고, Q는 탄소수 1 내지 10의 알킬렌이고, Y는 수소 또는 메틸기이고, n은 1 내지 50의 정수이고, *는 결합부위를 나타낸다)(Wherein R ₁ , R ₂ and R ₃ are each independently

, Wherein X ₁ and X ₂ are each independently * -O- * or * -S- *, Q is alkylene having 1 to 10 carbon atoms, Y is hydrogen or a methyl group, and n is an integer of 1 to 50 And * represents a binding site)

The optical sheet 100 is disposed on a light guide plate or other optical sheet in a liquid crystal display device, and refracts and emits light incident from a light guide plate or another optical sheet. The optical pattern layer 120 of the optical sheet 100 of the embodiment of the present invention includes the (meth) acrylic compound represented by the above formula (1) and the hmax of the optical pattern layer 120 is 3 탆 or more, Can be emitted at a high luminance, and scratch resistance can be enhanced. Specifically, the hmax of the optical pattern layer 120 may be 3 to 15 占 퐉, specifically 3 占 퐉 to 10 占 퐉, more specifically 3 占 퐉 to 8 占 퐉. The scratch resistance is excellent in the above-mentioned range, and the incident light can be emitted with high luminance.

6 is a conceptual diagram of hmax and? H. 6, "hmax" refers to an optical pattern of an optical pattern 100 of an optical sheet 100 of FIG. 1 by an indentor by micro indentation on an arbitrary portion of the optical pattern layer 120 When the optical pattern layer is pressed with an indenter under the measurement conditions of i) to iv), when the pressing force of the optical pattern layer with the indenter becomes 30 mN, It can be the depth into the layer:

[Measuring conditions]

i) Initial force at which the indenter presses the optical pattern layer: 0 mN

ii) the rate of increase per second of the force the indenter presses the optical pattern layer: 0.6 mN / s

iii) Direction in which the indenter presses the optical pattern layer: direction perpendicular to the optical pattern layer

iv) The indenter uses a bar having a circular cross section having a diameter of 50 μm.

For example, 'hmax' is obtained by preparing a specimen by cutting an optical sheet having an optical pattern layer in a width-by-height (5 cm x 5 cm) length, placing the optical pattern layer of the specimen on the indenter side of the micro- , The optical pattern layer was pressed in the vertical direction (gravity direction) with respect to the optical pattern with the indenter for 50 seconds, stopped for 5 seconds, and then again at a reduction rate of 0.6 mN / s Means the depth at which the indenter enters the optical pattern layer when the pressing force is 30 mN (i.e., when the pressing force is 50 seconds) when the indenter is released by reducing the pressing force. The indenter may be a circular bar having a cross-section of 50 mu m in diameter.

The optical pattern layer 120 may have a Δh of 1.3 μm or less, for example, 0 μm to 1.3 μm, specifically 0 μm to 0.9 μm, more specifically 0 μm to 0.7 μm, in the following formula (1) The optical sheet is not damaged by absorbing an external impact in the range of from 0 to 50 탆, and the scratch resistance of the optical sheet can be increased because the closer to 0 탆 the better the restoring force is:

<Formula 1>

H = h2 - h1

(Where h1 is the pressing force of the optical pattern layer with the indenter under the conditions of i) to iv), when the pressing force of the indenter on the optical pattern layer before reaching hmax is 5 mN, (Unit: 占 퐉) of the dentor into the optical pattern layer, and h2 is the refractive index of the optical pattern layer after reaching hmax when pressing the optical pattern layer with the indenter under the conditions of i) to iv) (Unit: 占 퐉) in which the indenter enters the optical pattern layer when the pressing force is 5 mN.

Referring to Fig. 6, &quot; DELTA h &quot; indicates an optical sheet having an optical pattern layer formed on an arbitrary portion of the optical pattern layer 120 of the optical sheet 100 of Fig. 1 in a transversal x vertical (5 cm x 5 cm) The optical pattern layer in the specimen was placed on the indenter side of the micro-indentation device. The pressing force was increased from 0 mN to 0.6 mN / s to increase the optical pattern layer with an indenter for 50 seconds. (H) when the indenter enters the optical pattern layer when the indenter is released by depressing it in the direction perpendicular to the layer (gravity direction), stopping for 5 seconds, and then decreasing the pressing force again at a rate of 0.6 mN / H1 is the depth at which the indenter enters the optical pattern layer when the pressing force before reaching hmax is 5mN and h2 is the pressing force after reaching hmax when hmax reaches hmax. The depth at which the indenter enters the optical pattern layer at 5 mN , And h2 - h1 is defined as h.

Specifically, the content of the (meth) acrylic compound in the optical pattern layer 120 of the optical pattern layer 120 or? H may be different depending on the required application.

In one embodiment, the optical pattern layer 120 comprises 5% to 40% by weight, specifically 10% to 30% by weight, more specifically 15% by weight to 5% by weight, of the (meth) 25% by weight, and Δh may be 0.5 μm to 1.3 μm, specifically 0.5 μm to 1.2 μm, more specifically 0.5 μm to 1.0 μm. The refractive index of the optical sheet 100 is high in the above-mentioned range, and the brightness of the optical display device can be increased.

In another embodiment, the optical pattern layer 120 comprises 25% to 75%, specifically 35% to 65%, more specifically 40% to 60% by weight of the (meth) acrylic compound of Formula 1 Wt%, and Δh may be 0 μm to 0.9 μm, specifically 0 μm to 0.7 μm, more specifically 0 μm to 0.5 μm. The optical pattern layer 120 is not affected by contact with the protective sheet or another optical sheet formed on at least one surface of the optical sheet 100 in the above-mentioned range, and thus the high brightness of the liquid crystal display device can be maintained.

Specifically, Q may be an ethylene group in the (meth) acrylic-based composition represented by Formula 1 contained in the optical pattern layer 120. When Q is an ethylene group, there is an advantage that the resilience and impact resistance can be increased by the fluidity of the ethylene oxide bonded to the triazine core.

In an embodiment, the optical sheet 100 may have X ₁ of R ₁ , R ₂ and R ₃ as * -S- * or * -O- *, preferably * -S- *. When X ₁ is * -S- *, triazine is adjacent to sulfur (S) to increase the polarizability, which is advantageous in that the refractive index of the (meth) acrylic compound can be increased.

In other embodiments, n of R ₁ , R ₂ and R _{3 above} may be an integer from 1 to 50, preferably an integer from 1 to 20, preferably an integer from 1 to 10. Within the above range, the viscosity, restoring force and impact resistance of the composition for forming an optical pattern containing the (meth) acrylic compound can be balanced.

The optical sheet 100 has a light exit surface as a top surface and a light incident surface as a bottom surface so that light incident from the bottom surface is emitted to the top surface, A pattern layer 120 may be included.

The base film 110 includes a light incident surface and supports the optical pattern layer 120. The thickness of the base film 110 is not limited, but may be 10 to 300 탆, specifically 50 to 125 탆, Lt; / RTI &gt;

The base film 110 can have a refractive index of 1.5 to 1.7, and can be used in the optical sheet in the above range, securing a refractive index of 1.59 or more of the optical sheet, and emitting light with high brightness.

The base film 110 may be formed of the same or different material as the optical pattern layer 120, and may be a transparent film formed of, for example, a thermoplastic resin or a composition containing the thermoplastic resin. Specifically, the thermoplastic resin may be a polyester resin including a polyethylene terephthalate resin and a polyethylene naphthalate resin, a polyacetal resin, a (meth) acrylic resin, a polycarbonate resin, a styrene resin, a vinyl resin, a polyphenylene ether Butadiene-styrene copolymer resin, poly (meth) acrylate resin, polyaryl sulfone resin, polyether sulfone resin, polyether sulfone resin, polyether sulfone resin, polyether sulfone resin, , A polyphenylene sulfide-based resin, and a fluorine-based resin.

The optical pattern layer 120 includes a light exit surface and refracts light emitted from the base film 110. The optical pattern layer 120 has one or more optical patterns formed on the base film, But the optical pattern is not limited to this. The optical pattern may be a prism having a polygonal cross section (a polygon having a number of sides of 4 to 10), a micro lens pattern, a lenticular lens pattern, an emboss pattern, or a combination thereof May be included.

Referring to FIG. 2, the height of the optical pattern layer 120, that is, the optical pattern may be the same or different for each pattern. Specifically, the height H may be 10 μm to 40 μm, for example, 10 μm to 30 μm And there is no moire in the above range, and a condensing effect can be obtained. The pitch P of the optical patterns 110 may be the same or different for each pattern. Specifically, the pitch may be 10 탆 to 60 탆, for example, 20 탆 to 60 탆. In this range, It can be effective. The apex angle alpha of the optical pattern can be 80 DEG to 100 DEG, and the brightness enhancement effect can be obtained in the above range.

According to one embodiment of the present invention, the optical sheet 100 of the present invention may have a refractive index of the optical pattern layer 120 of 1.50 to 1.70, for example, 1.52 to 1.67. There is an advantage that light incident at the above-mentioned range can be emitted with high luminance.

According to another embodiment, in the optical sheet 100 of the present invention, the AGP and the weight having a weight between 0 and 100 g are sequentially placed on the optical pattern layer 120, (Scratch resistance) of the initial weight at which the optical pattern layer 120 starts to be damaged after the round trip (AG Pol) is reciprocated three times may be 15 g or more, preferably 20 g or more. Even if a protective sheet or another optical sheet is further formed on the optical sheet 100 in the above range, the optical pattern is influenced by the contact of the optical pattern layer 120 with the protective sheet or the like, and the brightness of the liquid crystal display device is lowered There is an advantage that it can be prevented.

Hereinafter, the present invention will be described with reference to FIG. 3 of another embodiment. 3 is a perspective view of an optical sheet of another embodiment of the present invention.

3, an optical sheet 200 according to another embodiment of the present invention includes a base film 110, an optical pattern layer 120 formed on the base film 110, and a coating layer 130 formed below the base film 110. [ And the optical pattern layer 120 may have a refractive index of 1.50 or more and the optical pattern layer 120 may have a hmax of 3 占 퐉 or more, for example, 3 占 퐉 to 15 占 퐉. As a result, the refractive index of the optical sheet can be increased to increase the brightness and the scratch resistance can be improved. Further, since the coating layer 130 is further formed, the diffusing effect of the optical sheet can be further enhanced, and moir 辿 caused by the optical pattern can be prevented. Except that a coating layer is further formed, and therefore only the coating layer will be described in the following.

The coating layer 130 may be formed of an ultraviolet ray curable resin, and may have a thickness of 1 탆 to 10 탆, and may be used in the optical sheet in the above range.

The coating layer 130 may be a diffusion coating layer, and a pattern for diffusing function, for example, an irregular pattern may be formed. The concavo-convex pattern can be formed by a sand blast method, a hot press method, a casting method of a transparent resin, or a method of dispersing fine particles on the back surface of a substrate film. As an example, a method of transferring the concavo-convex pattern of the pull-up roll produced by the sand blasting method in which irregularities are formed by hitting the surface of the pull-up roll with a bead having a diameter of 1 탆 to 200 탆 is transferred to the other surface of the base film . Specifically, an ultraviolet curable resin is injected between a pull roll formed with a concavo-convex pattern and a base film so that the pull roll is allowed to pass over the base film while being in contact with the ultraviolet curable resin. At this time, it is possible to form the light-diffusing layer on the base film by curing the UV by irradiating the curable resin.

The composite optical sheet of the present invention may include the optical sheet of the embodiment of the present invention. A composite optical sheet according to an embodiment of the present invention will be described with reference to FIG.

4, the composite optical sheet 300 of the embodiment of the present invention includes a first optical film 310 including a first base film 305 and a first optical pattern layer 310 formed on the first base film 305, And a second optical pattern layer 330 formed on the first optical sheet 320 and formed on the second base film 335 and the second base film 335, (340), and the first optical sheet (320) or the second optical sheet (340) may include the optical sheet of the embodiment of the present invention.

Specifically, the first optical sheet 320 or the second optical sheet 240 may have different contents or restitution powers of the (meth) acrylic compound of Formula 1 of the optical pattern layers 310 and 330 depending on the required application.

For example, in the case of the first optical sheet 320, the amount of the (meth) acrylic compound of Formula 1 may be 5 wt% to 40 wt%, specifically 10 wt% to 30 wt% Specifically, it may contain 15 wt% to 25 wt%, and Δh may be 0.5 μm to 1.3 μm, specifically 0.5 μm to 1.2 μm, more specifically 0.5 μm to 1.0 μm. The refractive index of the first optical sheet 320 is high in the above-mentioned range, and the brightness of the optical display device can be increased.

In an embodiment, the first optical sheet comprises 35 to 60% by weight of a monomer having a refractive index of 1.62 or more, 5 to 40% by weight of a (meth) acrylic compound represented by Formula 1, and 20 to 50% % Of an optical pattern layer formed of a composition for forming an optical pattern. Within the above range, the balance of scratch resistance and restoring force is excellent.

The monomer having a refractive index of 1.62 or more can be used as a composition for forming an optical pattern together with the compound of Formula 1 and can be used without limitation as long as the refractive index is 1.62 or more.

Specifically, a compound represented by the following formula (3) can be used:

(3)

(여기서, 상기 R₃는 수소 원자 또는 메틸기이고, X₃는 -O- 또는 -N(R)-(R: 수소 원자 또는 탄소수 1 내지 10의 알킬기)이며, *는 결합 부위를 나타냄)이고, Y₁　및 Y₂　중 적어도 하나는

이며, n₁　및 n₂의 평균값은 각각 독립적으로 1 내지 4이다).R ₁ and R ₂ are each independently an alkylene group having 2 to 10 carbon atoms, an arylene group having 6 to 20 carbon atoms, an alkylarylene group or an arylalkylene group having 7 to 20 carbon atoms, Ar ₁ is a group having 6 to 10 carbon atoms X ₁ and X ₂ are each independently -O- or -S-, Y ₁ and Y ₂ are each independently a hydrogen atom, -OH, -SH, -NH ₂ or

(Wherein R ₃ is a hydrogen atom or a methyl group, X ₃ is -O- or -N (R) - (R is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms), and * At least one of Y ₁ and Y ₂ is

And the average values of n ₁ and n ₂ are independently 1 to 4).

이고, X₃는 -O- 또는 -N(R)-(R: 수소 원자 또는 탄소수 1 내지 10의 알킬기)일 경우, UV 경화 후 광학패턴과 기재필름과의 부착력이 우수하여 기재필름으로부터 광학패턴이 잘 떨어지지 아니한다.Preferably, Y &lt; _{1 &gt;} or Y &lt; _{2 &gt};

, And X ₃ is -O- or -N (R) - (R is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms), the adhesion between the optical pattern and the base film after UV curing is excellent, This does not fall well.

Monomers having a refractive index of 1.62 or more may include, for example, one or more of the following formulas (3-1) and (3-2):

[Formula 3-1]

.

.

[Formula 3-2]

The non-phosphorous monomer may be used as a composition for forming an optical pattern together with the compound of Formula (1). Specifically, the non-phosphorus monomer includes at least one of an arylene group having 6 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an arylalkylene group having 7 to 10 carbon atoms, and an arylalkyl group having 7 to 10 carbon atoms, By further lowering the refractive index difference with the monomer of the formula (1), compatibility of the composition for forming an optical pattern and transparency of the optical pattern can be improved.

For example, non-phosphorus monomers include [4- (phenylthio) phenyl] alkyl esters, including [4- (phenylthio) phenyl] methyl (meth) (1,4-phenylene alkylene) esters, and the like, but they are not limited thereto. They may be synthesized or used as commercially available products .

As another example, the second optical sheet 320 may contain 25 wt% to 75 wt%, specifically 35 wt% to 65 wt% of the (meth) acrylic compound of Formula 1, Specifically, it may contain 40 wt% to 60 wt%, and Δh may be 0 μm to 0.9 μm, specifically 0 μm to 0.7 μm, more specifically 0 μm to 0.5 μm. The optical pattern layer 330 is not affected by contact with the protective sheet or another optical sheet formed on at least one surface of the second optical sheet 340 in the above-described range, and high brightness of the liquid crystal display device can be maintained. ,

In an embodiment, the first optical sheet comprises 15 wt% to 40 wt% of a monomer having a refractive index of 1.62 or more, 25 wt% to 75 wt% of a (meth) acrylic compound represented by the following formula (1) By weight based on the total weight of the composition.

The monomers having a refractive index of 1.62 or more and non-phosphorus monomers are as described above.

4, the first optical sheet 320 emits the light incident from the light guide plate (not shown in FIG. 4) to the second optical sheet 340, and FIG. 4 shows that the first optical pattern layer 310 is a triangular prism Layer. However, the first optical pattern layer is not limited to this, and may include a prism, a microlens pattern, a lenticular lens pattern, an emboss pattern, or a combination thereof, the cross section of which is a polygon (polygon having 4 to 10 sides) can do.

4, the longitudinal direction of the first optical pattern layer 310 of the first optical sheet 320 is y1, the pitch direction thereof is x1, and the second optical pattern layer 330 of the second optical sheet 340 X2 in the longitudinal direction and y2 in the pitch direction, the angle formed by y1 and x2 may be about 85 to about 95 and may be about 90, for example.

The first optical sheet 320 and the second optical sheet 340 are in a detachable state without being adhered to each other.

The second optical sheet 340 is formed on the first optical pattern layer 310.

The refractive index of the first optical sheet 320 can be about 1.62 to about 1.70, and light can be emitted at a high luminance in the above range.

The first base film (305) may be formed of the same or different resin as the second base film (335).

The first optical pattern layer 310 may be formed of a conventional ultraviolet ray curable resin or may be formed of a composition for forming an optical pattern including the monomer of Formula 1 to increase the refractive index of the first optical sheet to emit light with high brightness have.

The optical display device of the present invention may include an optical sheet or a composite optical sheet of the embodiment of the present invention, and may be, for example, a liquid crystal display device. A liquid crystal display device according to an embodiment of the present invention will be described with reference to FIG. 5 is a perspective view of a liquid crystal display device according to an embodiment of the present invention.

5, a liquid crystal display 400 according to an exemplary embodiment of the present invention includes a light source 410, a light guide plate 420 for guiding light emitted from the light source 410, a reflective sheet 420 disposed below the light guide plate 420, A diffusion sheet 430 disposed on the top of the light guide plate 420 and a composite optical sheet 440 disposed on the top of the diffusion sheet 430. The composite optical sheet 440 includes the diffuser sheet 450, Of the composite optical sheet.

A light source cover 410a may be disposed outside the light source 410 of the backlight unit. Here, although not shown, a liquid crystal display panel and an antireflection layer are sequentially stacked on the liquid crystal display device 400 to constitute a liquid crystal display device.

The light source 410 generates light, and various light sources such as a linear light source lamp, a planar light source lamp, a CCFL, or an LED may be used.

The light guide plate 420 guides the light generated by the light source 410 to the diffusion sheet 430, and may be omitted when a direct-type light source is employed.

The reflective sheet 450 reflects light generated from the light source 410 and supplies the light to the diffusion sheet 430.

The diffusion sheet 430 diffuses and scatters the light incident through the light guide plate 420 and supplies the light to the composite optical sheet 540.

The composite optical sheet 440 functions to refract light incident through the diffusion sheet 430 and condense the light onto a plane of a liquid crystal display panel (not shown). The composite optical sheet 440 may be formed of various shapes such as a shape of a light collecting portion and an angle of an inclined surface of a light collecting portion according to various design goals such as high condensing efficiency, wide viewing angle, prevention of moire phenomenon, And combinations thereof, are commercially available.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to embodiments of the present invention. However, the following examples are provided to aid understanding of the present invention, and the scope of the present invention is not limited to the following examples.

Example

Production Example 1

114 mL (0.81 mol) of triethylamine, 50 g (0.271 mol) of cyanuric chloride and 500 mL of tetrahydrofuran (THF) were added to a 1 L round bottom flask and stirred. Then, 100 mL of tetrahydrofuran (THF) in which 63.5 g (0.81 mol) of 2-mercaptoethanol was dissolved was dropped dropwise for 20 minutes in a dropwise manner. Thereafter, the reaction was allowed to proceed at room temperature for 3 hours. After completion of the reaction, the white salt produced was removed from the vacuum filter. The obtained solid product was purified by column chromatography (elution: hexane / ethyl acetate = 5: 1) to give a pale yellow transparent liquid intermediate. (55.3 g, yield 66%).

15.5 g (0.05 mol) of the above-prepared intermediate 1,3,5-trimercaptoethanol triazine and 21 mL (0.15 mol) of triethylamine were added to a 1 L round bottom flask, The mixture was stirred at 0 DEG C for 30 minutes with 400 mL of tetrahydrofuran (THF). 13.6 g (0.15 mol) of acroylchloride dissolved in 50 mL of tetrahydrofuran (THF) was dropped dropwise at intervals of 10 minutes. The whole reaction mixture was stirred at 0 DEG C for about 1 hour, and the resulting salt was vacuum filtered. The resulting liquid product was washed several times with water to remove salt, and a pale yellow liquid (meth) acrylic compound (Preparation Example 1 of Table 1) was obtained without purification. (21.2 g, yield 90%, refractive index (RI): 1.57, viscosity 270 cps to 470 cps)

Production Example 2

114 mL (0.81 mol) of triethylamine, 50 g (0.271 mol) of cyanuric chloride and 500 mL of tetrahydrofuran (THF) were added to a 1 L round bottom flask and stirred. Then, 100 mL of tetrahydrofuran (THF) in which 63.5 g (0.81 mol) of 2-mercaptoethanol was dissolved was dropped dropwise for 20 minutes in a dropwise manner. Thereafter, the reaction was allowed to proceed at room temperature for 3 hours. After the completion of the reaction, the resulting salt was removed under reduced pressure. The obtained solid product was purified by short column chromatography (elution: hexane / ethyl acetate = 5: 1) to give a pale yellow primary intermediate. (55.3 g, yield 66%).

Then, 132 mL (0.15 mol) of ethylene oxide solution (50 g / L in methylenechloride solution, Sigma Aldrich) was added to the 500 mL round bottom flask, and then nitrogen gas was refluxed while stirring. Then, ₂ g (0.015 mol, 10 mol%) of AlCl ₃ was added and the mixture was further stirred for 1 hour. 15.5 g (0.05 mol) of the prepared 1,3,5-trimercaptoethanol triazine was dissolved in 200 mL of dichloromethane, and the solution was further stirred for 4 hours while dropwise at 0 ° C. The obtained liquid product was washed several times with water to remove unreacted ethyleneoxide and acid catalyst, and then methylene chloride was removed under reduced pressure to obtain a transparent liquid type target compound (second intermediate). (18 g, 82% yield)

15.5 g (0.05 mol) of the second intermediate prepared above and 21 mL (0.15 mol) of triethylamine were stirred in a 1 L round bottom flask at 0 占 폚 for 30 minutes with 400 mL of tetrahydrofuran (THF). 13.6 g (0.15 mol) of acroylchloride dissolved in 50 mL of tetrahydrofuran (THF) was dropped dropwise at intervals of 10 minutes. The whole reaction mixture was stirred at 0 ° C for about 1 hour, and the resulting salt was filtered off. The resulting liquid product was washed several times with water to remove salt, and pale yellow liquid (n = 2) (meth) acrylic compound (Preparation Example 2 of Table 1) was obtained without purification. (20 g, yield 85%, refractive index (RI): 1.55, viscosity 430 cps)

Production Examples 3 to 6

In order to prepare the (meth) acrylic compounds having the structures shown in Tables 1 and 2 below, the same procedure as in Production Example 2 was repeated except that 2-mercaptoethanol was replaced by ethane-1,2-dithiol or ethane- (Meth) acrylate compound was synthesized in the same manner as in Preparation Example 2 except that diol was applied or thiazine or oxirane was used to grow the functional group of triazine to adjust n, .

The control of n value can be controlled by multiplying the amount of ethylene oxide solution by n times the molar ratio of cyanuric chloride. For example, the n value can be adjusted by applying an ethylene oxide solution (50 g / L in methylenechloride solution, Sigma Aldrich) in the amount of 66 mL (0.15 mol) x n in Production Example 2.

Production Example 7

To prepare an acrylic compound having the structure shown in the following Table 2, ethane-1,2-dithiol was used instead of 2-mercaptoethanol in Production Example 2, and thiirane ) To synthesize an acrylic compound in the same manner as in Example 2 except that the functional group of triazine was grown to control n, and the presence of the following compound was confirmed.

Production Example 8

Except that an ethane-1,2-diol was used instead of 2-mercaptoethanol in Production Example 2 to prepare an acrylic compound having the structure shown in Table 2 below, an acrylic compound And the presence of the following compounds was confirmed.

Production Example 9

42.2 mL (0.3 mol) of triethylamine, 17.7 g (0.1 mol) of thiocyanuric acid and 250 mL of tetrahydrofuran (THF) were added to a 500 mL round bottom flask and stirred. Then 50 mL of tetrahydrofuran (THF), in which 34.5 g (0.33 mol) of methacryloyl chloride had been dissolved, was dropped dropwise for 10 minutes in a dropwise manner. The reaction was then allowed to proceed at room temperature for 2 hours. After completion of the reaction, the white salt produced was removed from the vacuum filter. The resulting solid product was washed several times with water (1 L x 2) to remove the resulting salt. The desired compound (Preparation Example 9 of Table 2) in pale yellowish transparent, solid form was obtained without further purification. (35 g, 92% yield)

The compounds used in the following Examples and Comparative Examples are as follows.

(A) a monomer having a refractive index of 1.62 or more: a compound represented by the following formula (2) was used.

(2)

(B) (meth) acrylic compound

Examples 1 to 8: The (meth) acrylic compounds of Production Examples 1 to 8 were respectively used.

Examples 9 to 16: The (meth) acrylic compounds of Preparation Examples 1 to 8 were used in amounts different from those of Examples 1 to 8 only.

- Comparative Examples 1 and 3: TMPTA (Trimethylolpropane triacrylate, Miramer M300, Miwon Special Chemical Co.) represented by the following formula was used.

Comparative Examples 2 and 4: The (meth) acrylic compound of Production Example 9 was used.

(C) Non-phosphorus monomer: HRI-84 (refractive index: 1.602) manufactured by Daerim Chemical Co., Ltd. was used.

Example 1

25 parts by weight of a monomer represented by the following formula 2, 45 parts by weight of the compound of Preparation Example 1, 24 parts by weight of a non-phosphorous monomer (HRI-84 manufactured by Daelim Chemical Co., refractive index: 1.602), 3 parts by weight of a crosslinking agent (PN662NT, refractive index: 1.503) and 3 parts by weight of initiator (TPO produced by BASF, refractive index: 1.6) were mixed and stirred to prepare a composition for forming an optical pattern. A composition for forming an optical pattern was coated on one surface of a PET (polyethylene terephthalate) film (manufacturer: MITSUBISHI, trade name, T910E, thickness: 75 μm) for a transparent base film, and the height was 12 μm, the pitch was 24 μm, An optical sheet was prepared by applying a pattern to a coating using a pattern roll having a triangular pattern knitted at 90 ° and curing at 350 mJ / cm ² .

(2)

Examples 2 to 8

An optical sheet was prepared in the same manner as in Example 1 except that the (meth) acrylic compound prepared in Production Examples 2 to 8 was used instead of the compound of Production Example 1.

Example 9

42 parts by weight of the monomer of the following formula 2, 12 parts by weight of the compound of the preparation example 1, 40 parts by weight of the non-phosphorus monomer (HRI-84 manufactured by Daerim Chemical Co., refractive index: 1.602), 3 parts by weight of a crosslinking agent (PN662NT, refractive index: 1.503) and 3 parts by weight of initiator (TPO produced by BASF, refractive index: 1.6) were mixed and stirred to prepare a composition for forming an optical pattern. A composition for forming an optical pattern was coated on one surface of a PET (polyethylene terephthalate) film (manufacturer: MITSUBISHI, trade name, T910E, thickness: 75 μm) for a transparent base film, and the height was 12 μm, the pitch was 24 μm, An optical sheet was prepared by applying a pattern to a coating using a pattern roll having a triangular pattern knitted at 90 ° and curing at 350 mJ / cm ² .

(2)

Examples 10 to 16

An optical sheet was prepared in the same manner as in Example 9 except that the (meth) acrylic compound prepared in Production Examples 2 to 8 was used instead of the compound of Production Example 1, respectively.

Comparative Examples 1 to 2

An optical sheet was prepared in the same manner as in Example 1 except that TMPTA was used in Comparative Example 1 instead of the compound of Preparation Example 1, and the compound of Preparation Example 9 was used in Comparative Example 2.

Comparative Examples 3 to 4

An optical sheet was prepared in the same manner as in Example 9 except that TMPTA was used in Comparative Example 3 instead of the compound of Preparation Example 1, and the compound of Preparation Example 9 was used in Comparative Example 4.

The properties of the prepared optical sheets were evaluated by the following methods, and the results are shown in Table 3 below.

Hmax (占 퐉) ? H (占 퐉) Refractive index Scratch resistance (g) Example 1 4.1 0.89 1.61 10 Example 2 4.5 0.87 1.61 10 Example 3 6.2 0.66 1.61 10 Example 4 8.5 0.52 1.60 20 Example 5 11.5 0.31 1.60 20 Example 6 13.8 0.19 1.59 20 Example 7 6.1 0.66 1.61 10 Example 8 6.2 0.65 1.61 10 Example 9 5.1 1.26 1.63 5 Example 10 5.2 1.25 1.63 5 Example 11 5.9 0.98 1.63 5 Example 12 7.1 0.82 1.63 7 Example 13 9.8 0.73 1.62 7 Example 14 11.9 0.59 1.62 7 Example 15 5.9 0.98 1.63 5 Example 16 6.0 0.97 1.62 5 Comparative Example 1 4.5 5 1.44 2 Comparative Example 2 3.8 4 1.49 One Comparative Example 3 4 7 1.49 2 Comparative Example 4 2 5 1.54 One

Property evaluation method

(1) hmax and? H: hmax and? H were measured using a microindentation measuring device FISHER SCOPE (HM2000XYp). The indenter is circular in cross section with a diameter of 50 mu m. The optical sheet on which the optical pattern layer was formed was cut to a width of 5 cm x 5 cm to prepare a specimen. The optical pattern layer of the specimen was placed on the indenter side of the micro-indentation device. Increasing the pressing force at an increasing rate of mN / s, pushing the optical pattern layer vertically in the gravity direction with the indenter for 50 seconds, stopping the indenter for 5 seconds, then decreasing the pressing force at 0.6 mN / s again When the indenter is released, a graph is drawn with the pressing force on the y-axis and the depth of the indenter in the optical pattern layer as the x-axis. The depth at which the indenter enters the optical pattern layer is hmax when the pressing force is 30 mN (when it is pressed for 50 seconds). hmax of the optical pattern layer is 5 mN when the indenter has reached the depth h1 and hmax when the indenter enters the optical pattern layer, Is the depth at which the optical pattern layer enters the optical pattern layer is h2, h2-h1 is DELTA h.

(2) Refractive index: Using the refractometer (model name: DTM-N, Japan ATAGO ABBE CO. LTD.), The refractive indexes of the optical sheets prepared in Examples and Comparative Examples were measured. The light source for the measurement was a 589.3 nm D-light sodium lamp.

(3) Scratch resistance: The optical pattern layer of the optical sheet was placed so as to face the AG layer of AG Pol (AG layer: TOPPAM Grade VH44, haze 20%) for 40 "TV, , Lift the AG Pol for 40 "TV 3 times at 5 cm intervals, and measure the weight of the first weight at which the optical pattern layer begins to be damaged. The larger the weight of the weight, the higher the scratch resistance.

As shown in Table 3, it can be seen that Examples 1 to 16, which fall within the scope of the present invention, exhibit excellent restitution, high brightness due to a high refractive index, and excellent scratch resistance.

On the other hand, in the case of Comparative Examples 1 to 4 which do not fall within the scope of the present invention, the restitution force is low and the scratch resistance is degraded.

Claims (14)

A base film and an optical pattern layer formed on one surface of the base film,
Wherein the optical pattern layer comprises a unit derived from a (meth) acrylic compound represented by the following formula (1)
Wherein the optical pattern layer is formed by pressing the optical pattern layer with an indenter in [Measuring Conditions] of i) to iv), and when the pressing force of the optical pattern layer with the indenter is 30 mN, An optical sheet having a depth hmax of 3 占 퐉 to 15 占 퐉, the depth of which enters the optical pattern layer:
[Chemical Formula 1]

(Wherein R ₁ , R ₂ and R ₃ are each independently

, Wherein X ₁ and X ₂ are each independently * -O- * or * -S- *, Q is alkylene having 1 to 10 carbon atoms, Y is hydrogen or a methyl group, and n is an integer of 1 to 50 And * represents a binding site)
[Measuring conditions]
i) Initial force at which the indenter presses the optical pattern layer: 0 mN
ii) the rate of increase per second of the force the indenter presses the optical pattern layer: 0.6 mN / s
iii) Direction in which the indenter presses the optical pattern layer: direction perpendicular to the optical pattern layer
iv) The indenter uses a bar having a circular cross section having a diameter of 50 μm.
2. The optical sheet according to claim 1, wherein the optical pattern layer has an optical thickness DELTA h of 1.3 [
<Formula 1>
H = h2 - h1
(Where h1 is the pressing force of the optical pattern layer with the indenter under the conditions of i) to iv), when the pressing force of the indenter on the optical pattern layer before reaching hmax is 5 mN, When the optical pattern layer is pressed by the indenter under the conditions of i) to iv), the pressing force of the indenter on the optical pattern layer after reaching the hmax is 5 mN The depth at which the indenter enters the optical pattern layer).
The optical element according to claim 2, wherein the optical pattern layer is formed of a composition for forming an optical pattern containing 25% by weight to 75% by weight of a (meth) acrylic compound represented by Formula 1, Optical sheet.
The optical element according to claim 2, wherein the optical pattern layer is formed of a composition for forming an optical pattern containing 5 to 40% by weight of a (meth) acrylic compound represented by Formula 1, Optical sheet.
The optical sheet according to claim 1, wherein the optical pattern layer has a refractive index of 1.50 to 1.70.
2. The optical element according to claim 1, wherein AGP Pol and AG Pol are sequentially reciprocated three times on the optical pattern layer in the state where the weight is between 0 and 100 g, Wherein the weight of the initial weight at which the layer starts to be damaged is 15 g or more.
The optical sheet according to claim 1, wherein the optical pattern layer is an ethylene group.
The optical sheet according to claim 1, wherein the optical sheet further comprises a coating layer on the other surface of the base film.
The first optical sheet, and
And a second optical sheet formed on the first optical sheet,
Wherein at least one of the first optical sheet and the second optical sheet comprises the optical sheet of claim 1.
The optical sheet according to claim 9, wherein the first optical sheet comprises an optical pattern layer formed of a composition for forming an optical pattern containing 5 to 40% by weight of a (meth) acrylic compound represented by the following general formula (1) 0.5 to 1.3 [micro] m composite optical sheet:
[Chemical Formula 1]

(Wherein R ₁ , R ₂ and R ₃ are each independently

, Wherein X ₁ and X ₂ are each independently * -O- * or * -S- *, Q is alkylene having 1 to 10 carbon atoms, Y is hydrogen or a methyl group, and n is an integer of 1 to 50 , And * indicates a binding site).
The optical sheet according to claim 10, wherein the first optical sheet comprises 35 to 60% by weight of a monomer having a refractive index of 1.62 or more, 5 to 40% by weight of a (meth) acrylic compound represented by the formula (1) To 50% by weight of an optical pattern layer formed of a composition for forming an optical pattern.
The optical sheet according to claim 9, wherein the second optical sheet comprises an optical pattern layer formed of a composition for forming an optical pattern containing 25% by weight to 75% by weight of a (meth) acrylic compound represented by the following formula Composite optical sheet having 0 占 퐉 to 0.9 占 퐉:
[Chemical Formula 1]

(Wherein R ₁ , R ₂ and R ₃ are each independently

, Wherein X ₁ and X ₂ are each independently * -O- * or * -S- *, Q is alkylene having 1 to 10 carbon atoms, Y is hydrogen or a methyl group, and n is an integer of 1 to 50 , And * indicates a binding site).
The optical sheet according to claim 12, wherein the first optical sheet comprises 15 to 40% by weight of a monomer having a refractive index of 1.62 or more, 25 to 75% by weight of a (meth) acrylic compound represented by the formula (1) To 40% by weight of an optical pattern layer formed of a composition for forming an optical pattern.
An optical display device comprising the optical sheet of claim 1 or the composite optical sheet of claim 9.

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