KR20140060224A - Resin film, polarizing plate comprising the same, method of producing the same and display apparatus comprising the same - Google Patents

Abstract

The present invention is to provide a novel and modified resin membrane which can improve scratch resistance and a manufacturing method of a resin membrane. In order to solve the problem, according to one aspect of the present invention, a resin membrane in which a plurality of hollow silica particles, a low refractive index layer comprising a coupling agent resin bonding the hollow silica particles and the coupling agent resin rebound wherein fluorine particles are distributed on the surface of a low refractive index layer and which has hollow silica particles in a content of 20 mass% or more and 60 mass% or less and fluorine particles in a content of 2.0 mass% or more and 10 mass% or less is provided.

Description

Technical Field [0001] The present invention relates to a resin film, a polarizing plate including the resin film, a method of manufacturing the same, and a display device including the resin film.

The present invention relates to a resin film, a polarizing plate including the same, a method of manufacturing the same, and a display device including the same.

For example, as disclosed in Patent Document 1, an antireflection film is often pasted on the surface of a liquid crystal monitor, a flat panel display, or the like. The antireflection film prevents reflection of light on the display surface, thereby improving the visibility of the display. The conventional antireflection film has a low refractive index layer with a low refractive index and a high refractive index layer with a refractive index higher than that of the low refractive index layer. The low refractive index layer includes hollow silica particles, an acrylic resin, a fluorinated acrylic resin, and an additive.

The hollow silica particles are silica particles having a hollow structure and have a role of lowering the refractive index of the low refractive index layer. The hollow silica particles have at least a photopolymerizable functional group. As the photopolymerizable functional group, an acryloyl group and a methacryloyl group are known. The photopolymerizable functional group is also referred to as an ionizing radiation curable group.

The acrylic resin serves as a binder for bonding the hollow silica particles together. The fluorinated acrylic resin serves to bind the hollow silica particles together and to lower the refractive index of the low refractive index layer. The additive binds to the functional group of the hollow silica particles distributed on the surface of the low refractive index layer, thereby imparting antifouling property and slip property to the low refractive index layer, that is, the antireflection film. As additives, silicon and fluoropolymers are known.

<Prior Art Literature>

<Patent Literature>

(Patent Document 1) JP2007-264221 A

However, when the additive is present on the surface of the low refractive index layer, its function is exerted. However, in the conventional low refractive index layer, the additive was distributed not only on the surface but also inside. The reason why the additive is distributed in the low refractive index layer is that the hollow silica particles and the fluorinated acrylic resin inhibit the bleed out (migration to the surface) of the additive. That is, the additive can not effectively move to the surface because the hollow silica particles become a barrier. Further, the additive is compatible with the fluorinated acrylic resin. For example, both the fluoropolymer and the fluorinated acrylic resin contain fluorine, and thus are likely to be friendly. That is, the additive stays in the vicinity of the fluorinated acrylic resin.

Therefore, the conventional low refractive index layer can not effectively localize the additive on the surface of the low refractive index layer. Further, the conventional additives were very soft because they were linear polymer. Therefore, although the conventional low refractive index layer has improved initial characteristics of antifouling property and slipperiness to some extent, these characteristics are remarkably lowered by surface wiping and the like, and as a result, scratches easily occur.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a novel and improved resin film and a resin film production method capable of improving scratch resistance.

In order to solve the above problems, according to one aspect of the present invention, there is provided a low refractive index layer comprising a plurality of hollow silica particles, a binder resin for bonding the hollow silica particles to each other, Wherein the content of the hollow silica particles is 20 mass% or more and 60 mass% or less, and the content of fluorine particles is 2.0 mass% or more and 10 mass% or less.

According to this aspect, the bulk fluorine particles having excellent antifouling property, slipperiness and scratch resistance can be effectively bleed out by the repulsive force of the binder resin. Thereby, the resin film can localize the fluorine particles on the surface of the low refractive index layer, so that scratch resistance, antifouling property and slipperiness can be improved. Further, the resin film may improve the film strength.

Here, the binder resin may include multi-branched acrylic resins formed by polymerization of multi-branched acrylate monomers or multi-branched acrylate oligomers.

According to this aspect, since the binder resin contains the multi-branched acrylic resin, the fluorine particles can be bleed out more effectively.

The multi-branched acrylate monomer may have a plurality of photopolymerizable functional groups bonded to any one of a branch point of a second generation or more and a branch point of a second or more generations.

According to this aspect, since the multi-branched acrylate monomer has a plurality of photopolymerizable functional groups bonded to any one of the branch point of the second generation or more and the branch point of the second or more generations, the fluorine particles can be more effectively bleed out.

According to another aspect of the present invention, there is provided a process for producing a hollow fiber membrane, comprising the steps of: mixing a plurality of hollow silica particles, an oligomer for a monomer or binder for a binder capable of bonding hollow silica particles to each other and a coating liquid comprising fluorine particles repelling with an oligomer for a monomer or binder for a binder A step of applying a coating liquid to the substrate, and a step of initiating a polymerization reaction of an oligomer for a monomer or a binder for a binder, wherein the content of the hollow silica particles is 20 mass% to 60 mass% Is not less than 2.0% by mass and not more than 10% by mass.

According to this aspect, the resin film can be easily prepared by applying the coating solution in which the respective materials are dissolved and by merely initiating the polymerization reaction of the oligomer for the binder or the oligomer for the binder.

INDUSTRIAL APPLICABILITY As described above, according to the present invention, the resin film can improve scratch resistance, stain resistance and slipperiness. Further, the resin film can also improve the film strength.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a side cross-sectional view schematically showing the structure of a resin film according to an embodiment of the present invention. FIG.
Fig. 2 is an explanatory diagram showing a schematic structure of a multi-branched acrylate monomer used in the embodiment. Fig.
3 is a cross-sectional view of a polarizing plate according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the specification and drawings, constituent elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description will be omitted. The terms "upper" and "lower" in this specification are based on the drawings, and "upper" may be changed to "lower" and "lower" may be changed to "upper" depending on the point of view. It will be understood that where a layer or structure is referred to herein as "on" or "on ", it encompasses not only just another layer or structure but also intervening layers or structures in between. On the other hand, a layer being referred to as "directly on" or "directly above" In the drawings, the thickness, length, width, and the like of the constituent elements are slightly enlarged in size and can be sufficiently changed by those skilled in the art.

<1. Structure of Resin Film>

First, the structure of the resin film 10 according to the present embodiment will be described with reference to Fig. The resin film 10 contains a low refractive index layer 10a and fluorine particles 40. [ The low refractive index layer 10a includes hollow silica particles 20, a binder resin 30, and a photo initiator. The refractive index of the low refractive index layer is 1.10-1.45. The resin film 10 of the present embodiment is suitably applied to, for example, an antireflection film, but it is suitably applied to other fields, for example, a field using a film having a low refractive index.

(Composition of hollow silica particles 20)

The hollow silica particles (hollow silica fine particles) 20 are nanoscale particles dispersed in the low refractive index layer 10a and having at least a photopolymerizable functional group. Specifically, the hollow silica particles 20 have outer layers, and the inside of the outer layers is hollow or porous. The outer layers and the porous body are mainly composed of silicon oxide. A plurality of photopolymerizable functional groups are bonded to the outer layers. The photopolymerizable functional group and the outer layer are bonded via at least one of a Si-O-Si bond and a hydrogen bond. Examples of the photopolymerizable functional group include an acryloyl group and a methacryloyl group. That is, the hollow silica particles 20 contain at least one of an acryloyl group and a methacryloyl group as a photopolymerizable functional group. The photopolymerizable functional group is also referred to as an ionizing radiation curable group. The hollow silica particles 20 may have at least a photopolymerizable functional group, and the number and kind of these functional groups are not particularly limited. The hollow silica particles 20 may have other functional groups, for example, a thermosetting functional group. Examples of the thermosetting functional group include a hydroxyl group, a silanol group, an alkoxy group, a halogen, a hydrogen, an isocyanate group and the like. The thermosetting functional group is bonded to the hollow silica particles 20 in the same manner as the photopolymerizable functional group.

The average particle diameter of the hollow silica particles 20 is not particularly limited, but is preferably 10 to 100 nm, more preferably 40 to 60 nm. When the average particle diameter is less than 10 nm, the hollow silica particles 20 tend to aggregate, so that the uniform dispersion of the hollow silica particles 20 may not be easy. When the average particle diameter exceeds 100 nm, the transparency of the low refractive index layer 10a may be deteriorated.

Here, the average particle diameter is an arithmetic mean value of the particle diameter of the hollow silica particles 20 (the diameter when the hollow silica particles 20 are assumed to be spheres). The particle diameter of the hollow silica particles 20 is measured by, for example, a laser diffraction / scattering particle size distribution meter (specifically, HORIBA LA-920). On the other hand, the laser diffraction / scattering particle size distribution meter is not limited to HORIBA LA-920. The refractive index of the hollow silica particles 20 varies depending on the refractive index required for the low refractive index layer 10a, but is, for example, 1.10 to 1.40, preferably 1.15 to 1.25. The refractive index of the hollow silica particles 20 is measured by, for example, simulation software (Lambda Research, Tracepro).

The content ratio of the hollow silica particles 20 (the mass% based on the total mass of the hollow silica particles 20, the binder resin 30, the fluorine particles 40, and the photoinitiator) is 20 to 60 mass% As described above, when the content of the hollow silica particles 20 is in this range, the characteristics of the resin film 10 are improved. The more preferable content of the hollow silica particles is more preferably 20 to 50 mass% . When the content of the hollow silica particles is in this range, the characteristics of the resin film 10 become better.

(Constitution of the binder resin 30)

The binder resin 30 has a network structure to connect the hollow silica particles 20 together. The binder resin 30 causes the fluorine particles 40 to be disposed on the surface of the low refractive index layer 10a by bleeding out the fluorine particles 40. [ In the present embodiment, the binder resin 30 is a multi-branched acrylic resin formed by polymerizing a hyper branch type acrylate monomer or a multi-branched type acrylate oligomer. The multi-branched acrylate oligomer is obtained by polymerizing multi-branched acrylate monomers.

Fig. 2 shows the structure of multi-branched acrylate monomer 50 as an example of multi-branched acrylate monomers. The multi-branched acrylate monomer 50 has a core portion 51, a plurality of branch points 52, a plurality of branch portions 53, and a plurality of photopolymerizable functional groups 54. The core portion 51 is a center portion of the multi-branched acrylate monomer 50, and is bonded to at least one branch portion 53. The core portion 51 may be composed of a single element or may be composed of organic residues. Examples of the single element include a carbon atom, a nitrogen atom, a silicon atom, and a phosphorus atom. Examples of the organic residues include various chain compounds and organic residues composed of cyclic compounds. A plurality of core portions 51 may be present.

The branch point 52 is a starting point of the branch portion 53 and at least three branch portions 53 extend from one branch point 52. [ The branch point 52 is connected to the core portion 51 or another branch point 52 via branch portions 53. [ The branch point 52 has the same configuration as that of the core portion 51. That is, the branch point 52 may be composed of a single element or may be composed of organic residues. The branch point 52 is referred to as a first generation, a second generation,... In order from the closest to the core portion 51. That is, the branch point 52 directly connected to the core portion 51 becomes the first generation, and the branch point 52 connected to the branch point 52 of the first generation becomes the second generation.

The multi-branched acrylate monomer used in the present embodiment has at least a branch of the second generation or more. For example, in the example shown in Fig. 2, the multi-branched acrylate monomer 50 has a fourth-generation fork 52a.

The branching section 53 connects the branch point 52 of the first generation and the branch point 52 of the kth generation (k is an integer of 1 or more) and the branch point 52 of the (k + 1) To the branch point 52 of the switch. The branch portion 53 is a coupling number (coupling hand) possessed by the core portion 51 or the branch point 52. On the other hand, it is preferable that the number of generation of the branch point is large. The greater the number of generations, the more complicated the network structure of multi-branched acrylate monomers. As described later, the more complex the network structure of the multi-branched acrylate monomer, the more strongly the fluorine particles 40 can be held, and the scratch resistance of the binder resin 30 is improved.

The photopolymerizable functional group 54 is specifically an acryloyl group or a methacryloyl group. There are a plurality of photopolymerizable functional groups 54, and the plurality of photopolymerizable functional groups 54 are bonded to the branch points 52 of the second generation or more. Of course, the photopolymerizable functional group 54 may be connected to the core portion 51 or the branch point 52 of the first generation. On the other hand, the number of photopolymerizable functional groups 54 in the multi-branched acrylate monomer is preferably as large as possible. This is because the larger the number of photopolymerizable functional groups 54, the larger the cross-linking density of the binder resin 30 and, furthermore, the network structure of the binder resin 30 can be complicated. As described later, the more complex the network structure of the binder resin 30, the stronger the fluorine particles 40 can be retained, and the scratch resistance of the binder resin 30 is improved.

Specific examples of the multi-branched type acrylate monomers include various types of acrylates such as polyester, polyamide, polyurethane, ether, polyether sulfone, polycarbonate, Monomers. The multi-branched acrylate monomer may be a Tadpole type dendrimer, a comet type dendrimer, a twin type dendrimer, a cylinder type dendrimer, or the like.

The multi-branched acrylate monomers having the above-described structure have the following characteristics. First, since the multi-branched acrylate monomer has a high surface tension (for example, 30 or more), the fluorine particles 40 can be effectively bleed out due to the difference in surface tension with the fluorine particles 40. The surface tension is measured by, for example, an automatic surface tension meter (specifically, DY-300 manufactured by Kyowa Interface Science Co., LTD). On the other hand, the automatic surface tension meter is not limited to Kyowa Interface Science DY-300. On the other hand, there are other multifunctional acrylate monomers having the surface tension in the above-mentioned range. However, as the present inventors have studied extensively, it has been found that the fluoride particles 40 can not be effectively bleed out unless they are multi-branched acrylate monomers lost. In the present specification, the surface tension is a value at 25 ° C and the unit is (mN / m).

The surface tension of fluorine particles is 10-22, and the surface tension of multi-branched acrylate monomers or oligomers is 20-35. Thus, the multi-branched acrylate monomer can bleed out the fluorine particles 40, so that the antifouling property, slipperiness, scratch resistance and the like of the resin film 10 can be improved. Further, the multi-branched acrylate monomer can reduce the fluorine particles 40 remaining in the low refractive index layer 10a. Therefore, the crosslinking density of the binder resin 30 is improved, and furthermore, the mechanical strength of the low refractive index layer 10a is improved.

Secondly, multi-branched acrylate monomers (or multi-branched acrylate oligomers polymerized with the monomers) have very low viscosity (mPa · s = cps) at room temperature (25 ° C) Therefore, the multi-branched acrylate monomer can largely flow even during drying, so that it is possible to help bleed out the fluorine particles 40.

That is, as described later, in order to produce the resin film 10, first, a multi-branched acrylate monomer (or multi-branched acrylate oligomer) and fluorine particles 40 are dissolved in a solvent to prepare a coating solution. Then, the coating liquid is applied onto a substrate and dried to form a coating layer. Then, the multi-branched acrylate monomer is polymerized by irradiating the coating layer with light. Thereby, the resin film 10 is formed. Here, although the bleed-out of the fluorine particles 40 occurs in the coated layer, the multi-branched acrylate monomer can greatly flow in the coated layer, and thus can help bleed out the fluorine particles 40.

On the other hand, it is generally known that increasing the number of photopolymerizable functional groups of acrylate monomers and oligomers increases the viscosity of acrylate monomers and oligomers. For example, as urethane-based acrylate oligomers, it is also known that the viscosity (mPa s s = cps) at room temperature (25 캜) is in the range of tens to hundreds of thousands. If the oligomer is used to form the resin film 10, it is expected that the oligomer will largely be prevented from moving in the coating layer, thereby greatly inhibiting the bleed-out of the fluorine particles 40.

On the other hand, from the viewpoint of viscosity, an acrylate monomer or oligomer having only a low viscosity may be used. However, since such a monomer or oligomer does not form a network structure even when polymerized, I can not.

The multi-branched acrylate monomers or oligomers have a viscosity of 600-900 mPa s at 25 캜.

Thirdly, multi-branched acrylate monomers can form a binder resin 30 (acrylic resin) having a very complicated network structure by polymerizing, so that it is possible to firmly retain the fluorine particles 40 by this network structure have.

That is, since the fluorine particles 40 do not particularly have a reactive functional group on the surface thereof, the binder resin 30 needs to physically retain the fluorine particles 40. At this point, since the acrylic resin formed by polymerization of the multi-branched acrylate monomer has a very complicated network structure, the fluorine particles 40 enter the network structure, and the fluorine particles 40 are strongly retained.

Fourth, since the multi-branched acrylate monomer can form a binder resin 30 (acrylic resin) having a very complicated network structure by polymerization, the scratch resistance is improved by this network structure.

That is, the fluorine particles 40 are distributed on the surface of the dried coating liquid by bleeding out in the coating layer. However, the fluorine particles 40 are not distributed without gaps on the surface of the coating layer, and gaps are formed between the fluorine particles 40 (see Fig. 1). Therefore, a part of the binder resin 30 is exposed on the surface. Therefore, the binder resin 30 also needs to have scratch resistance.

The scratch resistance of the binder resin 30 increases as the network structure of the binder resin 30 becomes complicated. The complexity of the network depends on the complexity of the network structure of the multi-branched acrylate monomers themselves and on the size of the cross-linking density of the binder resin 30. [ In this regard, multi-branched acrylate monomers have a very complex network structure. In addition, since multi-branched acrylate monomers have a large number of photopolymerizable functional groups, the crosslinking density of the binder resin 30 is also increased. Therefore, the scratch resistance of the binder resin 30 is also increased.

Fifth, multi-branched acrylate monomers are hardly affected by deterioration by light. As described above, the fluorine particles 40 are not distributed without gaps on the surface of the coating layer, and a gap is formed between the fluorine particles 40. [ In this gap, multi-branched acrylate monomers are exposed.

On the other hand, multi-branched acrylate monomers have photopolymerizable functional groups. The photopolymerizable functional group is easily radicalized by receiving light. Radicalized photopolymerizable functional groups readily react with oxygen in the atmosphere to form oxides (or peroxides). The participating photopolymerizable functional groups lose activity and can not react with other photopolymerizable functional groups.

Therefore, it is expected that some photopolymerizable functional groups among the plurality of photopolymerizable functional groups possessed by the multi-branched acrylate monomers exposed on the surface of the coating layer are inactivated. However, multi-branched acrylate monomers have a large number of photopolymerizable functional groups, so that even if some photopolymerizable functional groups are inactivated, the remaining photopolymerizable functional groups can react with other photopolymerizable functional groups. Further, since the multi-branched acrylate monomer has a complicated network structure, any one of the photopolymerizable functional groups reacts with the other photopolymerizable functional groups, thereby forming a complicated network structure. Thus, multi-branched acrylate monomers can form a complex network structure even if some photopolymerizable functional groups are inactivated. The binder resin 30 having a complex network structure can firmly hold the fluorine particles 40 and also has improved scratch resistance. Therefore, the multi-branched acrylate monomer is hardly affected by deterioration by light.

On the other hand, if the resin film 10 is to be formed of a non-multi-branched acrylate monomer, the photopolymerization action of the acrylate monomer is inactivated by light and oxygen. Here, since the acrylate monomer has only a small number of photopolymerizable functional groups, most of the photopolymerizable functional groups are inactivated. Therefore, the crosslinking density of the binder resin becomes very small. In addition, the structure of the acrylate monomer itself is also simple. Therefore, since the binder resin has a very simple structure, the fluorine particles 40 can not be retained and the scratch resistance is also lowered. That is, acrylate monomers that are not multi-branched are susceptible to deterioration by light.

Sixthly, the multi-branched acrylate monomer can bond strongly with the hollow silica particles 20 by reacting with the photopolymerizable functional groups of the hollow silica particles 20. On the other hand, the hollow silica particles 20 may be directly bonded to each other. That is, the photopolymerizable functional group of the hollow silica particles 20 binds to the photopolymerizable functional groups of the other hollow silica particles 20.

As described above, the multi-branched acrylate monomer (or oligomer) can effectively bleed out the fluorine particles 40 during the production of the resin film 10. Further, the multi-branched acrylate monomers can form a complex network structure by polymerizing with each other, so that the fluorine particles 40 can be firmly retained on the surface of the low refractive index layer 10a. Also, scratch resistance of the exposed portion of the binder resin 30 is improved. Further, the multi-branched acrylate monomer is hardly affected by deterioration due to light.

(Constitution of the fluorine particles 40)

The fluorine particles 40 are additives added to impart the antifouling property, the slip property, and the scratch resistance to the low refractive index layer 10a. The fluorine particles 40 are nanometer sized fluorine-introduced spherical polymers having a structure similar to multi-branched acrylate monomers. That is, the fluorine particles (40) are functional fine particles characterized by having a large number of terminal groups.

Specifically, the fluorine particle 40 is a multi-branched polymer having a core and a branch point of a second generation or more, and has a plurality of fluorine-based functional groups as terminal groups (corresponding to photopolymerizable functional groups of multi-branched acrylate monomers). The fluorine-based functional group is bonded to the branch point of the second generation or more.

Examples of the fluorine-based functional group include (per) fluoroalkyl group and (per) fluoro polyether group. The structure of the (per) fluoroalkyl group is not particularly limited. That is, the (per) fluoroalkyl group is a straight chain (for example, -CF ₂ CF ₃ , -CH ₂ (CF ₂ ) ₄ H, -CH ₂ (CF ₂ ) ₈ CF ₃ , -CH ₂ CH _{2 2) 4} H, and so on) although being, branch structure (e. _{g., CH (CF 3) 2,} CH 2 CF (CF 3) 2, CH (CH 3) CF 2 CF 3, CH (CH 3) (CF 2 ) ₅ CF ₂ H), and may be an alicyclic structure (preferably, a 5-membered ring or a 6-membered ring such as a perfluorocyclohexyl group, a perfluorocyclopentyl group, or an alkyl group substituted by them).

The (per) fluoropolyether group is a (per) fluoroalkyl group having an ether bond, and the structure thereof is not particularly limited. (Per) fluoropolyether groups include, for example, -CH ₂ OCH ₂ CF ₂ CF ₃ , -CH ₂ CH ₂ OCH ₂ C ₄ F ₈ H, -CH ₂ CH ₂ OCH ₂ CH ₂ C ₈ F ₁₇ , -CH ₂ CH ₂ OCF ₂ CF ₂ OCF ₂ CF ₂ H, and a fluorocycloalkyl group having 4 to 20 carbon atoms and having at least 5 fluorine atoms. Examples of the perfluoro poly ether group, _{e.g., - (CF 2) X O} (CF 2 CF 2 O) y, - [CF (CF 3) CF 2 O] x - [CF 2 (CF 3) _{], (CF 2 CF 2 CF} 2 O) can be given a _{x, (CF 2 CF 2 O} ) x or the like. Here, x and y are arbitrary natural numbers.

Since the fluorine particles 40 have fluorine-based functional groups at their end groups, the surface of the fluorine particles 40 is substantially covered with fluorine-based functional groups. Therefore, the fluorine particles 40 are in a very strong bulk form and have excellent antifouling property and slipperiness. In the present embodiment, since the fluorine particles 40 are bleed out onto the surface of the low refractive index layer 10a, the antifouling property, slipperiness and scratch resistance of the resin film 10 are remarkably improved.

The average particle diameter (diameter) of the fluorine particles 40 is not particularly limited, but is preferably 30 nm or less, more preferably 20 nm or less. When the average particle diameter of the fluorine particles 40 is within this range, the bleed-out property, the stain-proof property, and the scratch resistance are further improved.

Here, the average particle diameter is an arithmetic average value of the particle diameter of the fluorine particles 40 (the diameter when the fluorine particles 40 are assumed to be spheres). The particle diameter of the fluorine particles 40 is measured by, for example, a laser diffraction / scattering particle size distribution meter (specifically, HORIBA LA-920). On the other hand, the laser diffraction / scattering particle size distribution meter is not limited to HORIBA LA-920.

The surface tension of the fluorine particles 40 is not particularly limited as long as it is smaller than the surface tension of the multi-branched acrylate monomer, but is preferably 20 or less, more preferably 18 or less. When the surface tension of the fluorine particles 40 is within this range, bleeding-out, antifouling and scratch resistance are further improved.

The resin film 10 formed by bleeding out the fluorine particles 40 preferably has a contact angle of 108 ° or more, more preferably 100 ° or more, and most preferably 100-120 ° . This is because the antifouling property and scratch resistance are further improved when the contact angle becomes a value in these ranges.

On the other hand, the content of the fluorine particles 40 (mass% based on the total mass of the hollow silica particles 20, the binder resin 30, the fluorine particles 40, and the photoinitiator) is 2.0% by mass or more and 10% By mass or less, preferably 4.0% by mass or more and 8% by mass or less.

A part of the fluorine particles 40 protrudes slightly from the surface of the low refractive index layer 10a although the fluorine particles 40 are bleed out to the surface of the low refractive index layer 10a and are fixed at that position Reference). As a result, the scratch resistance of the resin film 10 is further improved. The fact that a part of the fluorine particles 40 protrudes slightly from the surface of the low refractive index layer 10a can be easily judged by measuring the contact angle of pure water, for example. In the low refractive index layer 10a, only a fluorine particle is present as a low surface tension material having a contact angle of pure water of 100 DEG or more. Therefore, if the contact angle of the pure water with the surface of the low refractive index layer 10a is 100 or more, it can be said that the fluorine particles 40 protrude slightly from the surface of the low refractive index layer 10a. Therefore, it can be confirmed that a part of the fluorine particles 40 is slightly protruded from the surface of the low refractive index layer 10a with a simple and good precision.

Further, the fluorine particles 40 may not have reactive functional groups on their surfaces. As described above, since the binder resin 30 is a multi-functional acrylic resin, the fluorine particles 40 are firmly retained by the complex network structure.

The photoinitiator is a material for initiating the photopolymerization, and the kind thereof does not matter. That is, in the present embodiment, all the photoinitiators can be used. However, it is preferable that the photoinitiator is hardly subjected to oxygen inhibition and has good surface hardenability.

The resin film can be used for an antireflection film application. Specifically, the resin film includes a polarizer, a first optical film formed on the upper portion of the polarizer, and a second optical film formed on the lower portion of the polarizer. The polarizer is coated on the upper portion of the first optical film, It can serve as a preventive film. The first optical film and the second optical film may be a protective film or a retardation film. Specific examples of the transparent film include polyester-based, cyclic polyolefin-based (COP), triacetyl Cellulose, acrylic, polycarbonate, polyether sulfone, polysulfone, polyamide, polyimide, polyarylate, and polyvinyl alcohol films, including cellulose (TAC) It does not.

<2. Method of Manufacturing Resin Film (10)

Next, a method of manufacturing the resin film 10 will be described. First, the hollow silica particles 20, the photoinitiator, the monomer for the binder (or the oligomer for the binder in which the monomer for binder is polymerized), and the fluorine particles 40 are put into a solvent and stirred to produce a coating solution. Here, the monomer for the binder is concretely a multi-branched acrylate monomer, and the oligomer for the binder is a multi-branched acrylate oligomer obtained by polymerizing multi-branched acrylate monomers. The kind of the solvent is not particularly limited, but a ketone-based solvent having a boiling point of 110 ° C or higher is suitably used. This is because the solvent can stably dissolve each material and easily bleed out the fluorine particles 40.

Subsequently, the coating liquid is applied (coated) to an arbitrary substrate and dried to form a coating layer. The substrate may be a substrate of a plastic material such as glass or silicon, or may be an optical film. In the case where the substrate is an optical film, an optical film on which a resin film is formed can be obtained, and a polarizing plate including a resin film can be produced when the polarizing plate is adhered to a polarizer. The optical film on which the resin film is formed can serve as a protective film or a retardation film for the polarizer used in the polarizing plate described above and also can provide an antireflection effect. On the other hand, the application method is not particularly problematic, and a known method is applied arbitrarily. At this time, the fluorine particles 40 are bleed out by the repulsive force from the multi-branched acrylate monomer, and are localized on the surface of the coating layer. Here, the multi-branched acrylate monomer flows in the coating layer to help bleed out the fluorine particles 40.

Then, a photopolymerization reaction is initiated. As a result, the binder resin 30 is formed while the fluorine particles 40 are retained on the surface by the binder resin 30. Thereby, the resin film 10 is formed.

As described above, since the multi-branched acrylate monomer can effectively bleed out the fluorine particles 40, the resin film 10 according to the present embodiment is produced in a very simple process. Further, since the fluorine particles 40 are distributed on the surface of the low refractive index layer 10a, it is not necessary to adhere the antifouling sheet separately to the surface of the low refractive index layer 10a.

<3. Polarizer>

Next, the polarizing plate will be described. The polarizing plate may include a resin film. As a result, the antireflection effect, the slipperiness, the scratch resistance, and the film strength improvement effect can be provided to the polarizing plate. 3, a polarizer 100 according to an exemplary embodiment of the present invention includes a polarizer 110, a first optical film 120 formed on an upper portion of the polarizer 110, a second optical film 120 formed on a lower portion of the polarizer 110, A film 130 and a resin film 140 formed on the first optical film 120. The resin film 140 may include a resin film according to one embodiment of the present invention.

The polarizer 110 may be manufactured from a film made of a polyvinyl alcohol-based resin. As the polyvinyl alcohol-based resin, polyvinyl alcohol, polyvinyl formal, polyvinyl acetal, or a saponified product of an ethylene-vinyl acetate copolymer can be used. The degree of saponification of the film made of the polyvinyl alcohol-based resin may be 99 mol% or more, preferably 99-99.5 mol%, the degree of polymerization may be 2000 or more, preferably 2000-2500, and the thickness may be 10 탆 to 200 탆. The polarizer 110 can be produced by dying and stretching iodine onto a film made of a polyvinyl alcohol-based resin. The stretching ratio may be 2.0-6.0. After stretching, the color correction step may be performed by immersing the boric acid solution and the aqueous potassium iodide solution. The thickness of the polarizer 110 may be 10 占 퐉 to 200 占 퐉 and may be used in a display device in the above range.

The first optical film 120 and the second optical film 130 may be formed of the above-mentioned transparent film as a protective film or a retardation film. Specifically, the first optical film may be a polyethylene terephthalate (PET) film, and the second optical film may be a cyclic polyolefin (COP) film. The first optical film 120 and the second optical film 130 may have a thickness of 10 to 200 탆 and may be used in a display device in the above range. Although the first optical film 120 and the second optical film 130 are formed directly on the polarizer 110 in FIG. 3, although not shown in FIG. 3, the first optical film 120 and the second optical film 130 2 optical film 130 may be formed on the upper and lower sides of the polarizer 110 respectively by an adhesive composition for a polarizing plate. Further, although not shown in Fig. 3, the second optical film may be formed on the display panel and the organic light emitting element by the pressure sensitive adhesive for the polarizing plate.

The resin film 140 may be formed of a resin film according to embodiments of the present invention, and may be formed at the uppermost portion of the polarizing plate to realize an antireflection effect. Although the resin film 140 is formed directly on the first optical film 120 in FIG. 3, a functional layer or an optional optical film (not shown in FIG. 3) may be interposed between the resin film and the first optical film. May be further intervened.

The polarizing plate can be produced by a conventional method. Specifically, a polarizer is manufactured by the above-described method, a resin film is coated on one surface of the first optical film, a first optical film is bonded to the upper surface of the polarizer with a surface facing the resin film, And then adhering the film.

<4. Display device>

Next, the display device will be described. The display device according to an embodiment of the present invention may include a resin film, or a polarizing plate including a resin film. The display device may be a liquid crystal display device, an organic light emitting diode display device, or the like.

Example

(Example 1)

Next, an embodiment of the present embodiment will be described. In Example 1, the resin film 10 was produced by the following production method.

(Manufactured by Sartomer Co., CN2304) of 45 mass% (parts by mass) as the oligomer for the binder, 50 mass% hollow silica fine particles (Surulia 4320 manufactured by Nikkaki Kagaku Kasei) 2% by mass of fluorine particles (FX-012, manufactured by Nissan Chemical Industries, Ltd.) as an additive and 3% by mass of a photopolymerization initiator (Irgacure 184 manufactured by BASF Japan) were prepared. Then, these materials were put into 8000 mass% of methyl isobutyl ketone (MIBK) and stirred to prepare a coating solution.

Here, the particle diameter of the hollow silica particles was 50 nm to 60 nm. Therefore, the average particle diameter also falls within this range. The refractive index of the hollow silica particles was 1.25. The surface tension of the multi-branched acrylate oligomer was 32.6, and the viscosity (mPa.s) at 25 DEG C was 750. The surface tension of the fluorine particles was 17.6. On the other hand, the measurement was performed by the above-described apparatus or simulation software.

Then, the coating liquid was applied onto a substrate made of PMMA, and the coating liquid was dried at 90 DEG C for about 1 minute to form a coating layer. Subsequently, the coating layer was cured by irradiating the coating layer with ultraviolet rays for 5 seconds (metal halide lamp: light quantity: 1000 mJ / cm ² ) with nitrogen atmosphere (oxygen concentration: 1000 ppm or less). Thus, a resin film was formed. The thickness of the resin film was about 110 nm. As a method of measuring the film thickness, for example, a visible spectroscopic ellipsometer SMART SE manufactured by HORIBA Co., Ltd. can be mentioned.

(Examples 2 to 9 and Comparative Examples 1 to 6)

Resin films according to Examples 2 to 9 and Comparative Examples 1 to 6 were prepared by carrying out the same treatment as in Example 1 except that the content of each material, the kind of additive, and the type of oligomer for the binder were changed. Table 1 summarizes the content ratios of the respective materials, the types of the additives, and the types of the monomers for the binder.

<Table 1>

In Table 1, the unmanned state indicates that the same materials as in Example 1 were used. Of the additives, * 1 is a linear reactive photoreactive fluoropolymer (KY-1203 from Shin-Etsu Chemical Co., Ltd., surface tension 16.7). * 2 is a linear reactive photoreactive fluoropolymer (OPTURU DAC, surface tension 16.9, available from Daikin Industries, Ltd.). * 3 is a photoreactive fluoropolymer (DIC RS77, surface tension 17.8).

Among the items of the acrylic resin, * 7 represents a multi-branched acrylate oligomer (CN2302, product of Sato MUSA Co., Ltd., surface tension 37.8, viscosity at 25 캜 (mPa s) 300).

(exam)

Then, the following SW rub-off test was performed on the resin films according to each of the examples and the comparative examples.

The surface of the substrate made of PMMA coated with the resin film was wiped 10 times by reciprocating wiping while multiplying the load in the vertical direction (vertical direction) by 500 g / cm ² . The wipes were Kim Wipes Wiper S-200 manufactured by Japan Paper Crescent Co., Ltd.

(evaluation)

The scratch resistance of the resin film after the SW rubbing test was evaluated. In addition, the contact angle and the haze value of each resin film after the SW rub-off test at the initial stage (before the SW rub-off test) were evaluated.

(Scratch resistance evaluation)

The scratch resistance was evaluated according to the following criteria.

Less than three scratches: ◎

4 to 5 scratches or less: ○

6 to 9 scratches: △

More than 10 scratches: ×

(Contact angle evaluation)

2 占 퐇 of pure water was dropped onto a substrate coated with a resin film using a fully automatic contact angle meter DM700 (Kyowa Interface Science Co., Ltd.), and the contact angle (占 was measured.

(Haze value evaluation)

The haze value was measured by a method in accordance with JIS-K-7136. The evaluation results are shown in Table 2.

<Table 2>

Comparing the examples and the comparative examples, the examples showed good initial properties as well as good properties after the SW rub-off test. On the other hand, in the comparative example, the initial characteristics were good, but the results after the SW rubbing test were not good. Therefore, it can be seen that good properties can be obtained by using fluorine particles as an additive, a binder resin as multi-branched acrylic resin, and a content ratio of each material within the above-mentioned range.

As described above, according to the present embodiment, the bulk fluorine particles 40 having excellent antifouling properties, slipperiness, and scratch resistance can be effectively bleed out by the repulsive force of the binder resin 30. [ Thereby, the resin film 10 can localize the fluorine particles 40 on the surface of the low refractive index layer 10a, thereby improving scratch resistance, antifouling property, and slippery property. Further, the resin film 10 can improve the film strength.

Since the binder resin 30 is composed of multi-branched acrylic resin, the fluorine particles 40 can be bleed out more effectively.

The multi-branched acrylate monomer constituting the multi-branched acrylic resin has a plurality of photopolymerizable functional groups (54) bonded to either the branch point (52) of the second generation or more and the branch point of the second or more generations, (40) can be bleed-out more effectively.

The resin film 10 can be formed simply by applying the coating solution in which the respective materials are dissolved and initiating the photopolymerization reaction.

While the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited thereto. It will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention as defined in the appended claims. But is to be understood as falling within the technical scope of the invention.

10: Resin film
20: hollow silica particles
30: binder resin
40: Fluorine particles
50: multi-branched acrylate monomer
100: polarizer, 110: polarizer, 120: first optical film, 130: second optical film, 140:

Claims (11)

A low refractive index layer comprising a plurality of hollow silica particles and a binder resin for bonding the hollow silica particles together;
And fluorine particles distributed on the surface of the low refractive index layer,
The content of the hollow silica particles is 20 mass% or more and 60 mass% or less,
Wherein the content of the fluorine particles is 2.0% by mass or more and 10% by mass or less. The resin film according to claim 1, wherein the binder resin comprises a multi-branched acrylic resin formed by polymerizing a multi-branched acrylate monomer or a multi-branched acrylate oligomer. The resin film according to claim 2, wherein the multi-branched acrylate monomer comprises a plurality of photopolymerizable functional groups bonded to any one of a branch point of a second generation or more and a branch point of the second generation or more. Producing a coating liquid comprising a plurality of hollow silica particles and an oligomer for a monomer or binder for a binder capable of bonding the hollow silica particles together and fluorine particles repelling the oligomer for the monomer or binder for the binder;
Applying the coating liquid to a substrate;
Initiating polymerization of the oligomer for the binder or binder for the binder,
The content of the hollow silica particles is 20 mass% or more and 60 mass% or less,
Wherein the content of the fluorine particles is 2.0% by mass or more and 10% by mass or less. The resin film according to claim 1, wherein the low refractive index layer has a refractive index of 1.10-1.45. The resin film according to claim 1, wherein the binder resin has a network structure. The resin film according to claim 1, wherein the resin film has a contact angle of 100-120 °. The resin film according to claim 1, wherein the fluorine particles have a spherical shape. The resin film according to claim 1, wherein the fluorine particle is a multi-branched polymer having a core and a plurality of fluorine-based functional groups at a terminal group having a branch point of a second generation or more. A polarizing plate comprising the resin film according to any one of claims 1 to 9. A display device comprising the polarizer of claim 10.

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