JP2014032229A - Optical component having hard coat layer, and optical management unit, backlight assembly and display including optical component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical component excellent in scratch resistance.SOLUTION: The optical component includes an optical functional layer having a first surface and a hard coat layer disposed on the first surface of the optical functional layer. The hard coat layer contains a mixture of nanoparticles and a binder. The nanoparticles constitute 40 mass% to 95 mass% of the whole mass of the hard coat layer; 10 mass% to 50 mass% of the nanoparticles have an average particle diameter in the range from 2 nm to 200 nm; and 50 mass% to 90 mass% of the nanoparticles have an average particle diameter in the range from 60 nm to 400 nm. A ratio of the average particle diameter of the nanoparticles having an average particle diameter in the range from 60 to 400 nm to the average particle diameter of the nanoparticles having an average particle diameter in the range from 2 nm to 200 nm ranges from 2:1 to 200:1.

Description

  The present disclosure relates to an optical component having a hard coat layer with improved scratch resistance, and a light management unit, a backlight assembly and a display including the optical component, and more particularly, an optical incorporated in an optical display device such as a liquid crystal display. The present invention relates to a component, and a light management unit, a backlight assembly and a display including the optical component.

  Optical components such as polarizing film, diffusion film, and prism film are used in LCDs such as laptop computers, mobile phones, and tablets for the purpose of improving brightness, uniforming the image quality in the display area, saving power, and reducing weight. It has been incorporated. These optical components are stacked in a direction perpendicular to the optical axis of the liquid crystal display. Therefore, when an external force such as a finger press or a drop impact is applied to the liquid crystal display, the prism structured surface of the prism film contacts the surface of another optical component and damages the surface, and the display quality of the liquid crystal display May deteriorate. Therefore, a hard coat treatment for protecting the surface of an optical film such as a polarizing film is generally performed.

US Pat. No. 5,104,929 and US Pat. No. 7,074,463 disclose hard coat materials comprising SiO ₂ nanoparticles modified with a photocurable silane coupling agent for the purpose of surface protection of optical display devices such as liquid crystal displays. It is described that it can be used.

Japanese Patent Application Laid-Open No. 2004-085925 discloses that, in a film having a hard coat layer formed by sequentially laminating a primer layer and a hard coat layer on at least one surface of a transparent substrate, the primer layer adheres to the transparent substrate. The force is applied to JIS-Z0237 after a primer layer formed with a film thickness of 0.1 to 1 μm and a transparent substrate are stacked on one side of the transparent substrate and pressurized with a pressure of 1 N / cm ² at room temperature. The compliant 180 degree peeling force is 0.001 to 4N, and the hydroxyl value A (KOHmg / g) of the pre-curing resin composition of the primer layer is 3 ≦ A ≦ 50, and before the hard coat layer is cured. A film having a hard coat layer characterized in that the hydroxyl value B (KOHmg / g) of the resin composition is 30 ≦ B ≦ 200 ”is described.

Japanese Patent Application Laid-Open No. 2010-211196 states that “a polarizing film made of a uniaxially stretched polyvinyl alcohol-based resin film in which iodine or a dichroic dye is adsorbed and oriented, and a resin film laminated on at least one surface of the polarizing film. The surface of the resin film opposite to the side facing the polarizing film was rubbed 10 times under the conditions of a load of 250 g / cm ² , a stroke width of 5 cm, and a speed of 50 reciprocations / minute using steel wool. The number of scratches at the time is 10 or less, and “polarizing plate which is a back side polarizing plate disposed between a liquid crystal cell and a backlight included in the liquid crystal display device” is described.

US Pat. No. 5,104,929 US Pat. No. 7,074,463 JP 2004-085925 A JP 2010-211196 A

  An object of the present disclosure is to provide an optical component such as a polarizing film, a diffusion film, and a prism film excellent in scratch resistance, and a light management unit, a backlight assembly, and a display including the optical component.

  According to an embodiment of the present disclosure, an optical component including an optical functional layer having a first surface, and a hard coat layer disposed on the first surface of the optical functional layer, the hard coat The layer comprises a mixture of nanoparticles and a binder, the nanoparticles comprising 40% to 95% by weight of the total weight of the hard coat layer, 10% to 50% by weight of the nanoparticles being 2 nm to 200 nm The average particle size of the nanoparticles having an average particle size in the range, 50% to 90% by weight of the nanoparticles having an average particle size in the range of 60 nm to 400 nm, and an average particle size in the range of 60 nm to 400 nm. An optical component is provided wherein the ratio of the diameter to the average particle size of nanoparticles having an average particle size in the range of 2 nm to 200 nm is in the range of 2: 1 to 200: 1.

  According to some other embodiments of the present disclosure, a light management unit, a backlight assembly, and a display including the optical component are provided.

  Since the hard coat layer highly filled with nanoparticles has high optical transparency, it does not affect the optical characteristics of the optical functional layer. According to the present disclosure, it is possible to obtain an optical component having desired optical characteristics and exhibiting both excellent scratch resistance and impact resistance. Moreover, the display excellent in durability can be obtained by using the optical component of this indication.

  The above description should not be regarded as disclosing all the embodiments of the present invention and all the advantages related to the present invention.

It is sectional drawing of the reflective polarizing film of one Embodiment of this indication. It is sectional drawing of the prism film of one Embodiment of this indication. 6 is a graph showing simulation results between mass ratios and packing ratios of small particle groups and large particle groups for several particle size combinations (small particle groups / large particle groups). It is sectional drawing of the liquid crystal display of one Embodiment of this indication. It is sectional drawing of the liquid crystal display of another embodiment of this indication. It is sectional drawing of the liquid crystal display of another embodiment of this indication. It is a schematic diagram of the steel wool abrasion resistance test apparatus used in the Example. It is a schematic diagram of the ET test apparatus used in the Example.

  Hereinafter, the present invention will be described in more detail for the purpose of illustrating representative embodiments of the present invention, but the present invention is not limited to these embodiments.

  In the present disclosure, “(meth) acryl” means “acryl or methacryl”, and “(meth) acrylate” means “acrylate or methacrylate”.

  An optical component according to an embodiment of the present disclosure includes an optical functional layer having a first surface, and a hard coat layer including a mixture of nanoparticles and a binder disposed on the first surface of the optical functional layer. Including. In some embodiments, the optical functional layer is selected from the group consisting of a reflective polarizing layer, an absorbing polarizing layer, a diffusing layer, and a prism layer having a prism structured surface. As these optical functional layers, for example, a reflective polarizing film, an absorptive polarizing film, a diffusing film, a prism film and the like used in the technical field of liquid crystal displays can be used.

  The reflective polarizing layer divides non-polarized light emitted from the light source into a reflected polarized light component (for example, S-polarized light) and a transmitted polarized light component (for example, P-polarized light). The transmitted polarized component is incident on the absorbing polarizing layer positioned above the reflective polarizing layer. On the other hand, the reflected polarized light component returns to the light source side, is reflected by the reflecting plate, and enters the reflective polarizing layer again. Since part of the reflected polarization component is depolarized by the reflective polarizing layer, part of the light incident on the reflective polarizing layer again can pass through the reflective polarizing layer and reach the absorbing polarizing layer. . When the reflective polarizing layer is used, the luminance of the liquid crystal display can be improved by reusing light from the light source.

  As the reflective polarizing layer, for example, a reflective polarizing film using a multilayer optical film (MOF), a diffuse reflective polarizing film (DRPF) such as a continuous / dispersed phase polarizer, a wire grid reflective polarizing film, a cholesteric reflective type A polarizing film etc. can be used. Both reflective polarizing films using MOF and diffuse reflective polarizing films including continuous / dispersed phase polarizers exploit the difference in refractive index between at least two materials, usually at least two polymer materials. . As the MOF reflective polarizing film, for example, one disclosed in US Pat. No. 5,882,774 can be used, and those available from 3M Company as the trade name “DBEF-Q” can be mentioned. As the DRPF, those disclosed in US Pat. Nos. 5,825,543, 5,867,316, and 5,751,388 can be used. Examples of the wire grid reflective polarizing film include those described in US Pat. No. 6,122,103. Examples of the cholesteric reflective polarizing film include those described in US Pat. No. 5,793,456 and US Patent Application Publication No. 2002/0159019. The cholesteric reflective polarizing film may be provided with a quarter-wave retardation layer on the exit surface, whereby the light transmitted through the cholesteric reflective polarizing film changes to linearly polarized light.

  The absorption-type polarizing layer absorbs light in one polarization state (for example, S-polarized light) and transmits light in the other polarization state (for example, P-polarized light) when receiving non-polarized light emitted from a light source, Polarized light is supplied to the liquid crystal layer of the liquid crystal display panel. The light from the light source may be transmitted through the reflective polarizing layer as necessary. In this case, the absorbing polarizing layer is a clean-up polarized light that absorbs light in one polarization state that has leaked through the reflective polarizing layer. Acts as a child. As the absorptive polarizing layer, an absorptive polarizing film exhibiting dichroism known in this technical field can be used, and examples thereof include those disclosed in US Pat. Nos. 6,610,356 and 6,096,375.

As the diffusion layer, a diffusion film known in the art can be used, and the diffusion film is usually a film obtained by subjecting the surface of the polymer film to a diffusion surface treatment by mat processing (including bead coating) or texture processing. The diffusion film can also be formed by subjecting the surface to another diffusing surface treatment such as sandblasting or arranging a plurality of minute protrusions, or can be formed by dispersing diffusing particles such as TiO ₂ inside. You can also. For example, the diffusion film can be formed by various molding methods from a composition containing a resin such as polycarbonate resin, acrylic resin, polyester resin, epoxy resin, polyurethane resin, polyamide resin, polyolefin resin, silicone resin (including modified silicone such as silicone polyurea). Can be produced. Specific examples of the diffusion film include a light diffusion film manufactured by Eiwa Co., Ltd. and “Opulse (trade name) series”. The diffusion film can be used in any thickness depending on the purpose of use, but is generally selected in consideration of thinning and weight reduction of the liquid crystal display device. The thickness of the diffusion film is usually , About 5 μm to about 1000 μm, preferably about 5 μm to about 500 μm, more preferably about 5 μm to about 200 μm. The thickness of the diffusion film is most preferably in the range of about 5 μm to about 150 μm.

  The prism layer has a prism structured surface that redirects light off the optical axis of the liquid crystal display in a direction closer to the optical axis. Thereby, the light quantity of an optical axis direction can be increased and the brightness | luminance of an image can be improved. As the prism layer, for example, a prism film having a prism-structured surface composed of a plurality of prism arrays that re-direct light from a light source by refraction and reflection can be used. Examples of such prism films include prism films available from 3M Company under the trade names “TBEF2-Tn”, “TBEF2-GT”, and “BEF4-GT”.

  The optical article may contain a combination of two or more optical functional layers. For example, the optical component may be a composite optical film that includes both a reflective diffusion layer and a prism layer having a prism structured surface.

  The thickness of the optical functional layer ranges from about 5 μm to about 1 mm (in some embodiments, from about 10 μm to about 500 μm, or from about 15 μm to about 200 μm), but the thickness is outside these ranges. However, it may be useful.

  FIG. 1 shows a cross-sectional view of a reflective polarizing film 10 that is an optical component according to an embodiment of the present disclosure. The reflective polarizing film 10 includes a reflective polarizing layer 12 having a first surface, and a hard coat layer 14 containing a mixture of nanoparticles and a binder disposed on the first surface of the reflective polarizing layer 12. Including. An absorptive polarizing film having an absorptive polarizing layer, a diffusing film having a diffusing layer, and the like may have a similar cross-sectional structure.

  A cross-sectional view of a prism film 20, which is an optical article of another embodiment of the present disclosure, is shown in FIG. The prism film 20 includes a prism layer 22 having a first surface (bottom surface in the drawing), and a hard coat layer 24 containing a mixture of nanoparticles and a binder disposed on the first surface of the prism layer 22. Including. The prism layer 22 in FIG. 2 has a prism structured surface on the top surface facing the bottom surface (first surface).

  Typical binders contained in the hard coat layer include resins obtained by polymerizing curable monomers and / or curable oligomers, resins obtained by polymerizing sol-gel glass, and the like. More specific examples of the resin include acrylic resin, urethane resin, epoxy resin, phenol resin, and polyvinyl alcohol. Furthermore, the curable monomer or curable oligomer can be selected from curable monomers or curable oligomers known in the art, and a mixture of two or more curable monomers, a mixture of two or more curable oligomers. Alternatively, a mixture of one or more curable monomers and one or more curable oligomers may be used. In some embodiments, the resin includes dipentaerythritol pentaacrylate (eg, available from Sartomer Company, Exton, Pa. Under the trade designation “SR399”), pentaerythritol triacrylate isophorone diisocyanate (IPDI) (eg, , Available from Nippon Kayaku Co., Ltd. (Tokyo, Japan) as trade name “UX-5000”), urethane acrylate (for example, trade name “UV1700B” and trade name “from Nippon Synthetic Chemical Industry Co., Ltd., Osaka, Japan)” UB6300B "), trimethylhydroxyl diisocyanate / hydroxyethyl acrylate (TMHDI / HEA, for example, trade name" Ebecryl 4 "from Daicel Cytec Co., Ltd., Tokyo, Japan) 858 ", polyethylene oxide (PEO) modified bis-A diacrylate (available from Nippon Kayaku Co., Ltd. (Tokyo, Japan) as trade name" R551 "), PEO modified bis-A epoxy Acrylate (for example, available as trade name “3002M” from Kyoeisha Chemical Co., Ltd. (Osaka, Japan)), silane-based UV curable resin (eg, trade name “SK501M” from Nagase ChemteX Corporation (Osaka, Japan)) Available), and 2-phenoxyethyl methacrylate (for example, available from Sartomer under the trade designation “SR340”); and those polymerized using mixtures thereof. For example, using 2-phenoxyethyl methacrylate in the range of about 1.0% to about 20% by weight has been observed to improve adhesion to polycarbonate. Bifunctional resins (eg PEO-modified bis-A diacrylate “R551”) and trimethylhydroxyl diisocyanate / hydroxyethyl acrylate (TMHDI / HEA) (eg available from Daicel Cytec Co., Ltd. under the trade name “Ebecryl 4858”) ) Has been observed to simultaneously improve the hardness, impact resistance and flexibility of the hard coat.

  The amount of binder in the hardcoat layer is typically from about 5% to about 60% by weight of the total weight of the hardcoat layer, in some embodiments from about 10% to about 40%, or about 15 mass% to about 30 mass%. According to the present disclosure, the hard coat layer can be formed even if the amount of the binder is relatively small.

  If necessary, the hard coat layer may be further cured with another curable monomer or curable oligomer. Typical curable monomers or curable oligomers include (a) 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, and 1,6-hexanediol. Monoacrylate monomethacrylate, ethylene glycol diacrylate, alkoxylated aliphatic diacrylate, alkoxylated cyclohexanedimethanol diacrylate, alkoxylated hexanediol diacrylate, alkoxylated neopentyl glycol diacrylate, caprolactone modified neopentyl glycol hydroxypivalate di Acrylate, caprolactone modified neopentyl glycol hydroxypivalate diacrylate, cyclohexanedimethanol diacrylate, diethyleneglycol Diacrylate, dipropylene glycol diacrylate, ethoxylated (10) bisphenol A diacrylate, ethoxylated (3) bisphenol A diacrylate, ethoxylated (30) bisphenol A diacrylate, ethoxylated (4) bisphenol A diacrylate, hydroxy Pivalaldehyde-modified trimethylolpropane diacrylate, neopentyl glycol diacrylate, polyethylene glycol (200) diacrylate, polyethylene glycol (400) diacrylate, polyethylene glycol (600) diacrylate, propoxylated neopentyl glycol diacrylate, tetra Ethylene glycol diacrylate, tricyclodecane dimethanol diacrylate, triethylene glycol diacrylate (B) glycerol triacrylate, trimethylolpropane triacrylate, ethoxylated triacrylate (eg ethoxylated (3) trimethylolpropane triacrylate) Ethoxylated (6) trimethylolpropane triacrylate, ethoxylated (9) trimethylolpropane triacrylate, ethoxylated (20) trimethylolpropane triacrylate, etc.), pentaerythritol triacrylate, propoxylated triacrylate (eg propoxylated) (3) Glyceryl triacrylate, propoxylated (5.5) Glyceryl triacrylate, propoxylated (3) Trimethylolpropane triacrylate, propylene Compounds having three (meth) acrylic groups such as ropoxylated (6) trimethylolpropane triacrylate), trimethylolpropane triacrylate, tris (2-hydroxyethyl) isocyanurate triacrylate; (c) ditrimethylolpropanetetra Acrylate, dipentaerythritol pentaacrylate, ethoxylated (4) compound having four or more (meth) acrylic groups such as pentaerythritol tetraacrylate, pentaerythritol tetraacrylate, caprolactone modified dipentaerythritol hexaacrylate; (d) Oligomeric (meth) acrylic compounds such as urethane acrylate, polyester acrylate, epoxy acrylate; the above polyacrylamide analogues; and this Include polyfunctional (meth) acrylic monomers and polyfunctional (meth) acrylate oligomer selected from the group consisting of. Such compounds are commercially available, and at least some are available from, for example, Sartomer, UCB Chemicals Corporation (Smyrna, GA), Aldrich Chemical Company, Milwaukee, Wis. Other useful (meth) acrylates include hydantoin moiety-containing poly (meth) acrylates as reported, for example, in US Pat. No. 4,262,072.

  Preferred curable monomers or curable oligomers contain at least three (meth) acrylic groups. Preferred commercially available curable monomers or curable oligomers are trimethylolpropane triacrylate (TMPTA) (trade name “SR351”), pentaerythritol tri / tetraacrylate (PETA) (trade names “SR444” and “SR295”), and Examples thereof include dipentaerythritol pentaacrylate (trade name “SR399”) available from Sartomer. Furthermore, a mixture of polyfunctional (meth) acrylate and monofunctional (meth) acrylate, such as a mixture of PETA and 2-phenoxyethyl acrylate (PEA), can also be used.

  The mixture of nanoparticles included in the hardcoat layer comprises about 40% to about 95% by weight of the total weight of the hardcoat layer, and in some embodiments, about 60% by weight of the total weight of the hardcoat layer. To about 90% by weight, or even about 70% to about 85% by weight. The mixture of nanoparticles comprises about 10% to about 50% by weight of nanoparticles having an average particle size in the range of about 2 nm to about 200 nm (hereinafter also referred to as a group of small particles or a first group of nanoparticles), and About 50% by mass to about 90% by mass of nanoparticles having an average particle size in the range of about 60 nm to about 400 nm (hereinafter also referred to as a group of large particles or a second group of nanoparticles). For example, the mixture of nanoparticles may comprise a first group of nanoparticles having an average particle size of about 2 nm to about 200 nm and a second group of nanoparticles having an average particle size of about 60 nm to about 400 nm of about 10:90 to about 50:50. It can be obtained by mixing at a mass ratio.

The average particle size of the nanoparticles can be measured with a transmission electron microscope (TEM) using techniques commonly used in the art. In measuring the average particle size of the nanoparticles, the sol sample was placed on a 400 mesh copper TEM grid with an ultra-thin carbon substrate on top of mesh lacey carbon (available from Ted Pella Inc. (Redding, Calif.)). By dripping, a sol sample for a TEM image can be prepared. Some of the droplets can be removed by contacting the side or bottom of the grid with the filter paper. The remainder of the sol solvent can be removed by heating or standing at room temperature. Thereby, particles can be left on the ultrathin carbon substrate, and imaging can be performed with the minimum interference from the substrate. The TEM image can then be recorded at a number of locations across the grating. Enough images are recorded to allow particle size measurements of 500-1000 particles. The average particle size of the nanoparticles can then be calculated based on the measured particle size in each sample. The TEM image can be obtained using a high-resolution transmission electron microscope (available under the trade name “Hitachi H-9000” from Hitachi High-Technologies Corporation) operating at 300 KV (using a LaB ₆ source). The images can be recorded using a camera (eg, available from Gatan, Inc. (Pleasanton, Calif.) Under the trade name “GATAN ULTRASCAN CCD”: model number 895, 2k × 2k chip). Images can be taken at 50,000x and 100,000x magnifications. In some samples, images can be taken at a magnification of 300,000 times.

Typically, the nanoparticles are inorganic particles. Examples of the inorganic particles include alumina, tin oxide, antimony oxide, silica (SiO, SiO ₂ ), zirconia, titania, ferrite and other inorganic oxides, a mixture thereof, or a mixed oxide thereof; metal vanadate, Examples thereof include metal tungstate, metal phosphate, metal nitrate, metal sulfate, and metal carbide. An inorganic oxide sol can be used as the inorganic oxide nanoparticles. For example, in the case of silica nanoparticles, silica sol obtained using water glass (sodium silicate solution) as a starting material can be used. Since silica sol obtained from water glass has a very narrow particle size distribution depending on the production conditions, the use of such silica sol can control the filling rate of nanoparticles in the hard coat layer more accurately, and can achieve desired characteristics. Can be obtained.

  The average particle size of the group of small particles ranges from about 2 nm to about 200 nm. Preferably, it is about 2 nm to about 150 nm, about 3 nm to about 120 nm, or about 5 nm to about 100 nm. The average particle size of the large group of particles ranges from about 60 nm to about 400 nm. Preferably, it is about 65 nm to about 350 nm, about 70 nm to about 300 nm, or about 75 nm to about 200 nm.

  The mixture of nanoparticles comprises a particle size distribution of at least two different nanoparticles. The particle size distribution of the mixture of nanoparticles may exhibit bimodality or multimodality that peaks at the average particle size of the group of small particles and the average particle size of the group of large particles. In addition to the particle size distribution, the nanoparticles may be the same or different (eg, compositionally surface modified or not surface modified). In some embodiments, the ratio of the average particle size of nanoparticles having an average particle size in the range of about 2 nm to about 200 nm and the average particle size of nanoparticles having an average particle size in the range of about 60 nm to about 400 nm is 2: 1 to 200: 1, and in some embodiments 2.5: 1 to 100: 1, or 2.5: 1 to 25: 1. Examples of preferable combinations of average particle diameters include 5 nm / 190 nm, 5 nm / 75 nm, 20 nm / 190 nm, 5 nm / 20 nm, 20 nm / 75 nm, 75 nm / 190 nm, or 5 nm / 20 nm / 190 nm. By using a mixture of nanoparticles having different sizes, it is possible to fill the hard coat layer with a large amount of nanoparticles and increase the hardness of the hard coat layer.

  Further, for example, by selecting the type, amount, size, and ratio of the nanoparticles, the transparency (such as haze) and hardness can be changed. In some embodiments, a hardcoat layer that combines the desired transparency and hardness can be obtained.

  The mass ratio (%) between the group of small particles and the group of large particles can be selected depending on the particle size used or a combination of particle sizes used. The preferred mass ratio can be selected according to the particle size used or a combination of particle sizes used, using software available under the trade name “CALVOLD2”, for example, a combination of particle sizes ( Selection of the model for Estimating the Void Fraction in can be selected based on simulations between the mass ratio of small particle groups and large particle groups and the packing factor for small particle groups / large particle groups) a Three-Component Randomly Packed Bed, "See also M. Suzuki and T. Shima: Powder Technol., 43, 147-153 (1985)). The simulation result is shown in FIG. According to this simulation, the mass ratio (small particle group: large particle group) is about 45:55 to about 13:87 or about 40:60 to about 15:85 at a combination of 5 nm / 190 nm; The mass ratio is about 45:55 to about 10:90 or 35:65 to about 15:85 in the 75 nm combination; the mass ratio is about 45:55 to about 10:90 in the 20 nm / 190 nm combination; 5 nm The mass ratio is about 50:50 to about 20:80 for the combination of 20 nm / 20 nm; the mass ratio is about 50:50 to about 22:78 for the combination of 20 nm / 75 nm; Preferably from about 50:50 to about 27:73.

  In some embodiments, the preferred combination of particle size and nanoparticles can be used to increase the amount of nanoparticles that fill the hardcoat layer and adjust the transparency and hardness of the resulting hardcoat layer can do.

  The thickness of the hard coat layer is generally in the range of about 80 nm to about 30 μm (in some embodiments, about 200 nm to about 20 μm, or about 1 μm to about 10 μm), but thicknesses outside these ranges Even in some cases, it can be usefully used. By using a mixture of nanoparticles of different sizes, it may be possible to obtain a hard coat layer that is thicker and harder.

  If necessary, the surface of the nanoparticles may be modified using a surface treatment agent. Generally, the surface treatment agent is a first end that binds to the particle surface (via covalent bonds, ionic bonds, or strong physisorption), renders the particles compatible with the resin, and / or is resin during curing. And a second end that reacts with. Examples of surface treating agents include alcohols, amines, carboxylic acids, sulfonic acids, phosphonic acids, silanes, and titanates. The preferred type of surface treatment is determined in part by the chemistry of the nanoparticle surface. Silane is preferred when silica and other siliceous fillers are used as the nanoparticles. In the metal oxide, silane and carboxylic acid are preferable. The surface modification can be performed either before, during, or after mixing with the curable monomer or curable oligomer. When silane is used, the reaction between the silane and the nanoparticle surface is preferably performed before mixing with the curable monomer or curable oligomer. The required amount of surface treatment agent depends on several factors such as the particle size and type of the nanoparticles, the molecular weight and type of the surface treatment agent. In general, it is preferred that approximately one surface treatment agent layer adhere to the surface of the particles. The required deposition procedure or reaction conditions also depend on the surface treatment used. When silane is used, the surface treatment is preferably carried out at high temperature for about 1 hour to about 24 hours under acidic or basic conditions. Surface treatment agents such as carboxylic acids usually do not require high temperatures and long time.

  Representative examples of the surface treatment agent include, for example, isooctyltrimethoxysilane, polyalkylene oxide alkoxysilane (for example, available from Momentive Specialty Chemicals, Inc. (Columbus, OH) under the trade name “SILQUEST A1230”), N— (3-triethoxysilylpropyl) methoxyethoxyethoxyethyl carbamate, 3- (methacryloyloxy) propyltrimethoxysilane (available from Alfa Aesar (Ward Hill, Mass.) Under the trade designation “SILQUEST A174”), 3- ( Acryloyloxy) propyltrimethoxysilane, 3- (methacryloyloxy) propyltriethoxysilane, 3- (methacryloyloxy) propylme Rudimethoxysilane, 3- (acryloyloxy) propylmethyldimethoxysilane, 3- (methacryloyloxy) propyldimethylethoxysilane, 3- (methacryloyloxy) propyldimethylethoxysilane, vinyldimethylethoxysilane, phenyltrimethoxysilane, n-octyl Trimethoxysilane, dodecyltrimethoxysilane, octadecyltrimethoxysilane, propyltrimethoxysilane, hexyltrimethoxysilane, vinylmethyldiacetoxysilane, vinylmethyldiethoxysilane, vinyltriacetoxysilane, vinyltriethoxysilane, vinyltriisopropoxy Silane, vinyltrimethoxysilane, vinyltriphenoxysilane, vinyltri (t-butoxy) silane, vinyltri (isobutoxy) Silane, vinyltriisopropenoxysilane, vinyltris (2-methoxyethoxy) silane, styrylethyltrimethoxysilane, mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, acrylic acid, methacrylic acid, oleic acid, stearin Compounds such as acid, dodecanoic acid, 2- [2- (2-methoxyethoxy) ethoxy] acetic acid (MEEAA), β-carboxyethyl acrylate, 2- (2-methoxyethoxy) acetic acid, methoxyphenylacetic acid, and mixtures thereof. Can be mentioned.

  If necessary, the binder of the hard coat layer may further contain known additives such as an ultraviolet absorber, an antifouling agent, an antifogging agent, a leveling agent, and an antistatic agent.

  In some embodiments, an ultraviolet absorber is included in the hard coat layer binder. In this embodiment, the optical component can be protected from ultraviolet rays contained in the light emitted from the light source. The ultraviolet absorber can be mixed with a curable monomer or a curable oligomer. Known ultraviolet absorbers can be used, for example, benzophenone (for example, available under the trade name “Uvinul 3050” from BASF AG), benzotriazole (eg, available under the trade name “Tinvin 928” from BASF AG) ), Triazine-based (for example, available from BASF AG under the trade name “Tinuvin 1577”), salicylate-based, diphenylacrylate-based, cyanoacrylate-based UV absorbers, and hindered amine light stabilizers (HALS) (for example, BASF) The trade names “Tinuvin 292” and “Tinvin 622” from AG can be used. By using a combination of a known ultraviolet absorber and a hindered amine light stabilizer, the ultraviolet absorptivity of the hard coat layer can be further increased as compared with the case where each is used alone.

  The amount of the ultraviolet absorber added is, for example, from about 0.01 parts by weight to about 20 parts by weight (in some embodiments, about 0.1 parts by weight with respect to 100 parts by weight in total of the nanoparticles, the curable monomer, and the curable oligomer). 1 part by mass to about 15 parts by mass, or about 0.2 part by mass to about 10 parts by mass). In certain embodiments, an optical component that includes a UV absorber in the hardcoat layer can achieve UV transmission of less than 3%.

  In some embodiments, an antifouling agent is included in the binder of the hard coat layer. When an antifouling agent is used, adhesion of dust and the like to the hard coat layer surface can be prevented. A fluorinated (meth) acrylic compound can be used as an antifouling agent. Examples of the fluorinated (meth) acrylic compound include HFPO urethane acrylate or modified HFPO as described in JP-A-2008-538195. The fluorinated (meth) acrylic compound is included in the binder of the hard coat layer as an unreacted fluorinated (meth) acrylic compound, as a reaction product reacted with a curable monomer or curable oligomer, or as a combination thereof. . As an antifouling agent, a silicone polyether acrylate (for example, available from Evonik Goldschmidt GmbH (Essen, Germany) under the trade name “TEGORAD2250”) can also be used.

In the present disclosure, the _{HFPO, F (CF (CF 3} ) CF 2 O) n CF (CF 3) - (n is 2 to 15) includes perfluoroether moiety represented by, and such a perfluoroether site Means a compound.

  The antifouling agent is preferably a polyfunctional fluorinated (meth) acrylic compound. Since the polyfunctional fluorinated (meth) acrylic compound has a plurality of (meth) acrylic groups, it can react with a curable monomer or curable oligomer as a crosslinking agent, or a functional group contained in a binder at a plurality of sites. Can interact non-covalently with the group. As a result, antifouling durability can be enhanced. When a polyfunctional fluorinated (meth) acrylic compound is used as an antifouling agent, the coefficient of friction on the surface of the hard coat layer may be lowered to improve scratch resistance in some cases. When a polyfunctional fluorinated (meth) acrylic compound having 3 or more (meth) acrylic groups is used, the antifouling durability can be further improved.

  The polyfunctional fluorinated (meth) acrylic compound is preferably a perfluoroether compound having two or more (meth) acrylic groups because the perfluoroether group imparts excellent antifouling properties to the hard coat layer.

As the perfluoroether compound having two or more (meth) acryl groups, for example, a polyfunctional perfluoroether (meth) acrylate described in JP2008-538195A, JP2008-527090A, or the like is used. it can. As such a polyfunctional perfluoroether (meth) acrylate, specifically,
_{HFPO-C (O) N (} H) CH (CH 2 OC (O) CH = CH 2) 2;
_{HFPO-C (O) N (} H) C (CH 2 CH 3) (CH 2 OC (O) CH = CH 2) 2;
_{HFPO-C (O) NHC (} CH 2 OC (O) CH = CH 2) 3;
_{HFPO-C (O) N (} CH 2 CH 2 OC (O) CH = CH 2) 2;
_{HFPO-C (O) NHCH 2} CH 2 N (C (O) CH = CH 2) CH 2 OC (O) CH = CH 2;
_{HFPO-C (O) NHCH (} CH 2 OC (O) CH = CH 2) 2;
_{HFPO-C (O) NHC (} CH 3) (CH 2 OC (O) CH = CH 2) 2;
_{HFPO-C (O) NHC (} CH 2 CH 3) (CH 2 OC (O) CH = CH 2) 2;
_{HFPO-C (O) NHCH 2} CH (OC (O) CH = CH 2) CH 2 OC (O) CH = CH 2;
_{HFPO-C (O) NHCH 2} CH 2 CH 2 N (CH 2 CH 2 OC (O) CH = CH 2) 2;
_{HFPO-C (O) OCH 2} C (CH 2 OC (O) CH = CH 2) 3;
_{HFPO-C (O) NH (} CH 2 CH 2 N (C (O) CH = CH 2)) 4 CH 2 CH 2 NC (O) -HFPO;
_{CH 2 = CHC (O) OCH} 2 CH (OC (O) HFPO) CH 2 OCH 2 CH (OH) CH 2 OCH 2 CH (OC (O) HFPO) CH 2 OCOCH = CH 2;
_{HFPO-CH 2 O-CH 2} CH (OC (O) CH = CH 2) CH 2 OC (O) CH = CH 2
Etc.

The polyfunctional perfluoropolyether (meth) acrylate is, for example, a poly (hexafluoropropylene oxide) ester such as HFPO-C (O) OCH ₃ or a poly (hexafluoropropylene oxide) acid halide: HFPO-C (O). HFPO with HFPO-amide polyol or polyamine, HFPO-ester polyol or polyamine, HFPO-amide, or mixed amine and alcohol groups by reacting F with a material containing at least three alcohols or primary or secondary amino groups Synthesis through the first step of producing an ester, the second step of (meth) acrylating the alcohol group and / or amine group with (meth) acryloyl halide, (meth) acrylic anhydride, or (meth) acrylic acid To do You can. _{Alternatively, HFPO-C (O) N} (H) CH 2 CH 2 CH 2 N (H) CH 3 and the like adducts of trimethylol propane triacrylate (TMPTA), reactive perfluoroalkyl ether and poly (meth) acrylate It can also be synthesized using a Michael type addition reaction.

  As a polyfunctional fluorinated (meth) acrylic compound, the perfluoroether moiety is divalent, and both ends thereof are directly or via other groups or bonds (ether bond, ester bond, amide bond, urethane bond, etc.) ( Those having a (meth) acryl group bonded thereto are preferred. While not being bound by any theory, such a compound is more firmly bonded to the hard coat layer to enhance the antifouling durability, and the perfluoroether portion between the (meth) acryl groups is the hard coat layer. It is considered that it is easy to move to the surface and orient in the in-plane direction, and as a result, the antifouling property can be sufficiently developed.

  The polyfunctional fluorinated (meth) acrylic compound may contain siloxane units. When the nanoparticles are inorganic oxides, multifunctional fluorinated (meth) acrylic compounds containing siloxane units are not only the reaction of (meth) acrylic groups with curable monomers or curable oligomers, It is considered that the interaction with the particles allows the hard coat layer to be held more firmly, and the antifouling durability can be further enhanced. The nanoparticles are preferably silica nanoparticles that are chemically similar to siloxane bonds and have high affinity.

  The polyfunctional fluorinated (meth) acrylic compound containing a siloxane unit has, for example, one ethylenically unsaturated group added to a linear or cyclic oligosiloxane or polysiloxane (hydrogensiloxane) containing 3 or more Si—H bonds. Alternatively, a perfluoropolyether compound having two or more is added (hydrosilylation) in the presence of a platinum catalyst or the like in an amount of less than 1 equivalent with respect to the Si—H bond, and the hydroxyl group-containing ethylenic group is added to the remaining Si—H bond. Similarly, a saturated compound can be synthesized by addition (hydrosilylation) in the presence of a platinum catalyst and the like, and then reacting a hydroxyl group with epoxy (meth) acrylate, urethane (meth) acrylate, or the like. The partial molecular weight of the perfluoroether moiety calculated from the chemical formula can be 500-30000.

  The siloxane unit is preferably a cyclic siloxane unit derived from tetramethylcyclotetrasiloxane, pentamethylcyclopentasiloxane or the like in order to sufficiently exhibit the antifouling property due to the fluorinated site. The number of silicon atoms constituting the cyclic siloxane unit is preferably 3-7.

Examples of the polyfunctional fluorinated (meth) acrylic compound containing a siloxane unit include perfluoropolyether compounds having two or more (meth) acrylic groups described in JP 2010-285501 A. For example, the compounds of the formulas (19) and (21) in the same publication are divalent perfluoropolyether groups: —CF ₂ (OCF ₂ CF ₂ ) _p (OCF ₂ ) _q OCF ₂ — (p / q = 0. 9, p + q≈45), each having a structure in which cyclic siloxanes having 4 silicon atoms are bonded to both ends, and three acryloyloxy groups are bonded to these cyclic siloxanes via urethane bonds. The hard coat layer can be suitably used.

  The amount of the antifouling agent added is, for example, from about 0.01 parts by weight to about 20 parts by weight (in some embodiments, about 0.1 parts by weight with respect to 100 parts by weight in total of the nanoparticles, the curable monomer, and the curable oligomer). 1 part by mass to about 10 parts by mass, or about 0.2 part by mass to about 5 parts by mass).

  In some embodiments, an antifogging agent is included in the binder of the hard coat layer. In this embodiment, it is possible to prevent dew condensation inside the apparatus when a notebook personal computer including a liquid crystal display, a mobile phone, a tablet or the like is used in an environment with a large temperature change. The antifogging agent can be mixed with a curable monomer or a curable oligomer. As an antifogging agent, anionic, cationic, nonionic or amphoteric surfactants can be used, for example, sorbitan monostearate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monobehenate, sorbitan and alkylene Sorbitan surfactants such as glycol condensate and fatty acid ester; glycerol monopalmitate, glycerol monostearate, glycerol monolaurate, diglycerol monopalmitate, glycerol dipalmitate, glycerol distearate, diglycerol Glycerin-based surfactants such as monopalmitate / monostearate, triglycerin monostearate, triglyceryl distearate, or alkylene oxide adducts thereof; polyethylene glycol monostearate Polyethylene glycol surfactants such as polyethylene glycol monopalmitate and polyethylene glycol alkylphenyl ether; trimethylolpropane surfactants such as trimethylolpropane monostearate; pentaerythritol monopalmitate, pentaerythritol monostearate Pentaerythritol surfactants such as alkylene oxide adducts of alkylphenols; esters of sorbitan / glycerin condensates with fatty acids, esters of sorbitan / alkylene glycol condensates with fatty acids; diglycerin dioleate sodium lauryl sulfate, Sodium dodecylbenzenesulfonate, cetyltrimethylammonium chloride, dodecylamine hydrochloride, lauric acid laurylamide Phosphate, triethyl cetyl ammonium iodide, oleyl amino diethylamine hydrochloride, dodecyl pyridinium salts, and isomers thereof. The antifogging agent may have a functional group that reacts with the curable monomer or curable oligomer.

  The amount of the antifogging agent added is, for example, about 0.01 parts by mass to about 20 parts by mass with respect to a total of 100 parts by mass of the nanoparticles, the curable monomer, and the curable oligomer (in some embodiments, about 0.1 parts by mass). 1 part by mass to about 15 parts by mass, or about 0.2 part by mass to about 10 parts by mass).

  The hard coat precursor that can be used to form the hard coat layer is a mixture of the above nanoparticles, curable monomers and / or curable oligomers, initiators, and optionally methyl ethyl ketone (MEK) or 1-methoxy. It includes the above-mentioned additives such as a solvent such as 2-propanol (MP-OH), an ultraviolet absorber, an antifouling agent, an antifogging agent, a leveling agent, and an antistatic agent. The hard coat precursor of an embodiment includes a mixture of nanoparticles and a binder, the nanoparticles comprising 40% to 95% by weight of the total weight of the nanoparticles and binder, and 10% to 50% by weight of the nanoparticles. % Has an average particle size in the range of 2 nm to 200 nm, 50% to 90% by weight of the nanoparticles have an average particle size in the range of 60 nm to 400 nm, and an average particle size in the range of 60 nm to 400 nm. The ratio of the average particle size of the nanoparticles to the average particle size of the nanoparticles having an average particle size in the range of 2 nm to 200 nm is in the range of 2: 1 to 200: 1.

  As is generally known in the art, specific components of the hardcoat precursor can be combined to prepare the hardcoat precursor. For example, two or more different size modified or unmodified nanoparticle sols are mixed with a curable monomer and / or curable oligomer together with an initiator in a solvent and the solvent added to form the desired solid The hard coat precursor can be prepared by adjusting the content. As the reaction initiator, for example, a photoinitiator or a thermal polymerization initiator known in this technical field can be used. Depending on the curable monomer and / or curable oligomer used, the solvent may not be used.

  When using surface-modified nanoparticles, the hard coat precursor can be prepared as follows, for example. Inhibitors and surface modifiers are added to the solvent in a container (eg, in a glass bottle), and the resulting mixture is added to the aqueous solution in which the nanoparticles are dispersed, followed by stirring. The container is sealed and placed in an oven, for example at high temperature (eg 80 ° C.) for several hours (eg 16 hours). The water is then removed from the solution, for example using a rotary evaporator at high temperature (eg 60 ° C.). Solvent is added to the solution and then evaporated to remove residual water from the solution. It may be preferable to repeat the latter half of the steps several times. By adjusting the amount of solvent, the concentration of nanoparticles can be adjusted to a desired concentration (mass%).

  Techniques for applying a hard coat precursor (solution) to the surface of an optical functional layer are known in the art, such as bar coating, dip coating, spin coating, capillary coating, spray coating, gravure coating, and screen printing. Is mentioned. The coated hard coat precursor can be dried, if necessary, and cured by a polymerization method known in the art such as a photopolymerization method using ultraviolet rays or an electron beam or a thermal polymerization method. Thus, an optical component of the present disclosure can be obtained by forming a hard coat layer on the optical functional layer.

  In some embodiments, in order to improve the adhesion between the hard coat layer and the optical functional layer, the surface of the optical functional layer is subjected to primer treatment, or a primer layer is disposed on the surface of the optical functional layer.

  Primer treatment is known in the art, and examples include surface treatment such as plasma treatment, corona discharge treatment, flame treatment, electron beam irradiation, surface roughening, ozone treatment, chemical oxidation treatment using chromic acid or sulfuric acid. It is done.

  As a material for the primer layer, for example, a (meth) acrylic resin (a (meth) acrylate homopolymer, a copolymer of two or more (meth) acrylates, or a copolymer of (meth) acrylate and another polymerizable monomer) Coalesced), urethane resin (for example, two-component curable urethane resin composed of polyol and isocyanate curing agent), (meth) acryl-urethane copolymer (for example, acrylic-urethane block copolymer), polyester resin, butyral resin , Chlorinated polyolefins such as vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, chlorinated polyethylene, chlorinated polypropylene, and copolymers and derivatives thereof (for example, chlorinated ethylene-propylene copolymer, Chlorinated ethylene-vinyl acetate copolymer, acrylic modified chlorinated Polypropylene, maleic acid-modified chlorinated polypropylene anhydride, urethane-modified chlorinated polypropylene) and the like.

  The primer layer can be formed by applying a primer solution prepared by dissolving the above resin in a solvent by a method known in the art and drying it. The thickness of the primer layer generally ranges from about 0.1 μm to about 20 μm (in some embodiments, from about 0.5 μm to about 5 μm).

  Hereinafter, the light management unit, the backlight assembly, and the display using the optical component of the present disclosure will be described with reference to FIGS. 4 to 6. It should not be construed that the present invention is limited to the embodiment.

  An example of a general configuration of a liquid crystal display used for a cellular phone or the like is shown in FIG. The liquid crystal display 50 includes, in order from the bottom, a reflecting plate 38, a light guide plate 36 in which the light source 42 is disposed on the side, a diffusion layer 32, and two prism layers 22A in which the upwardly facing prism rows are orthogonal to each other. And 22B, the reflective polarizing layer 12, the absorptive polarizing layer 16, the adhesive layer 18 for adhering these polarizing layers, and the liquid crystal display panel 44 connected to the controller 46. FIG. 4 shows an edge light system in which the light source 42 is disposed on the side of the light guide plate 36. However, a direct type system in which the light source is disposed under the diffusion layer without using the light guide plate is used depending on the application. It can also be adopted.

  As a light source, a cold cathode fluorescent tube, a filament lamp, an arc lamp, a light emitting diode (LED), a flat fluorescent panel, or the like can be used. A specular reflector or a diffuse reflector can be used as the reflector. Examples of the specular reflector include polyester-based multilayer optical films available from 3M Company under the trade names “ESR” and “ESR2”. Examples of the diffuse reflector include polymer sheets such as polyethylene terephthalate (PET), polycarbonate (PC), polypropylene (PP), and polystyrene (PS) filled with diffuse reflective particles such as titanium dioxide, barium sulfate, and calcium carbonate. It is done. As a light guide plate, one surface of a tapered polymer plate such as polymethyl methacrylate (PMMA), polycarbonate (PC), or polycycloolefin (COP) is provided with dots, grooves, irregularities, etc. of reflective material In addition, those known in this technical field can be used.

  In the embodiment shown in FIG. 4, hard coat layers 14 and 24 are disposed on the lower surface of the reflective polarizing layer 12 and the lower surface of the prism layer 22A, respectively. The hard coat layers 14 and 24 face the prism structured surfaces of the underlying prism layers 22A and 22B, respectively, and protect the reflective polarizing layer 12 and the prism layer 22A from scratches caused by these prism structured surfaces. ing. In the embodiment in which the mat coating is applied to the lower surface of the prism layer 22A, the hard coat layer may not be disposed under the prism layer 22A. The dashed line in FIG. 4 indicates the optical axis of the liquid crystal display.

  The liquid crystal display 50 shown in FIG. 4 includes two prism layers 22A and 22B arranged such that the prism rows are orthogonal to each other, but in some embodiments there is one prism layer. In this case, the hard coat layer may not be disposed on the lower surface of the prism layer. Also, in FIG. 4, the absorbing polarizing layer 16 is bonded to the reflective polarizing layer 12 via an adhesive layer 18, but in some embodiments the absorbing polarizing layer is spaced from the reflective polarizing layer. Or disposed on the lower surface of the liquid crystal display panel.

  For example, a light management unit according to an embodiment of the present disclosure includes a prism having an optical component including a reflective polarizing layer (12) and a hard coat layer (14), and a prism structured surface facing the hard coat layer (14). A film (22A) is included at least. The light management unit may further include an absorptive polarizing layer (16), and may further include an additional prism film (22B). The light management unit of another embodiment of the present disclosure includes an optical component including a prism layer (22A) having a prism structured surface and a hard coat layer (24), and a prism structured surface facing the hard coat layer (24). At least a prism film (22B). The light management unit may further include a diffusion layer (32), a light guide plate (36), a reflection plate (38), or a combination thereof.

  In the liquid crystal display 52 shown in FIG. 5 used for a mobile phone of a type different from FIG. 4, the composite optical film 26 in which the two optical functional layers of the prism layer 22A and the reflective polarizing layer 12 are integrated is used. The hard coat layer 24 is disposed on the lower surface of the reflective polarizing layer 12. The hard coat layer 14 is also disposed on the lower surface of the absorption polarizing layer 16. The hard coat layers 14 and 24 face the prism structured surfaces of the prism layers 22A and 22B below the hard coat layers 14 and 24, respectively, and the absorbing polarizing layer 16 and the reflective polarizing layer 12 are separated from scratches by these prism structured surfaces. Protect. In the embodiment in which the matte coating is applied to the lower surface of the reflective polarizing layer 12, the hard coat layer may not be disposed under the reflective polarizing layer 12.

  The liquid crystal display 52 shown in FIG. 5 includes two prism layers 22A and 22B arranged such that the prism rows are orthogonal to each other, but in some embodiments the prism layer 22B is not used. In this case, the hard coat layer may not be disposed on the lower surface of the reflective polarizing layer 12. Moreover, the absorption-type polarizing layer 16 may be disposed on the lower surface of the liquid crystal display panel.

  For example, a light management unit according to an embodiment of the present disclosure includes a prism having an optical component including an absorption-type polarizing layer (16) and a hard coat layer (14), and a prism structured surface facing the hard coat layer (14). The film (composite optical film 26) is included at least. The light management unit may further include an additional prism film (22B). The light management unit of another embodiment of the present disclosure includes an optical component including a prism layer (22A) having a prism-structured surface and a reflective polarizing layer (12) and a hard coat layer (24), and a hard coat layer (24 At least a prism film (22B) having a prism-structured surface facing. The light management unit may further include a diffusion layer (32), a light guide plate (36), a reflection plate (38), or a combination thereof.

  In the liquid crystal display 54 shown in FIG. 6 used for a tablet or the like, an additional diffusion layer 32B is disposed between the reflective polarizing layer 12 and the prism layer 22A, and a hard coat layer is formed on the lower surface of the diffusion layer 32B. 34 is arranged. Further, the hard coat layers 14 and 24 are also disposed on the lower surface of the reflective polarizing layer 12 and the lower surface of the prism layer 22A, respectively. The hard coat layers 14 and 34 face the prism structured surface of the underlying prism layer 22A, and protect the reflective polarizing layer 12 and the diffusing layer 32B from scratches and the like by the prism structured surface. The hard coat layer 24 faces the prism structured surface of the underlying prism layer 22B, and protects the prism layer 22A from scratches and the like by the prism structured surface. In the embodiment in which the mat coating is applied to the lower surface of the diffusion layer 32B and / or the prism layer 22A, the hard coat layer may not be disposed below the diffusion layer 32B and / or the prism layer 22A.

  The liquid crystal display 54 shown in FIG. 6 includes two prism layers 22A and 22B arranged such that the prism rows are orthogonal to each other, but in some embodiments there is one prism layer. In this case, the hard coat layer may not be disposed on the lower surface of the prism layer. In FIG. 6, the absorbing polarizing layer 16 is bonded to the reflective polarizing layer 12 via the adhesive layer 18, but in some embodiments, the absorbing polarizing layer is spaced from the reflective polarizing layer. Or disposed on the lower surface of the liquid crystal display panel.

  For example, the light management unit according to an embodiment of the present disclosure includes an optical component including a diffusion layer (32B) and a hard coat layer (34), and a prism film having a prism structured surface facing the hard coat layer (34). 22A) at least. The light management unit includes an additional prism film (22B), a reflective polarizing film (12), an absorbing polarizing film (16), a diffusion layer (32), a light guide plate (36), a reflective plate (38), or these Further combinations may be included.

  According to some embodiments of the present disclosure, a backlight assembly including a light source and the light management unit, and a display including the light source, a liquid crystal display panel, and the light management unit are provided.

  The components of the light management unit, backlight assembly and display may be fixedly placed in the frame, with or without optically transparent adhesive, diffusing adhesive, or optical diffusion between the components You may adhere | attach using the contact bonding layer which consists of an acrylic foam tape.

  In the following examples, specific embodiments of the present disclosure are illustrated, but the present invention is not limited thereto. All parts and percentages are by weight unless otherwise specified.

<Evaluation method>
The characteristics of the reflective polarizing film having the hard coat layer of the present disclosure were evaluated according to the following methods.

1. Steel Wool Abrasion Resistance Test The scratch resistance of the hard coat layer disposed on the surface of the reflective polarizing film was evaluated by the surface change after the steel wool abrasion resistance test. In the steel wool abrasion resistance test, # 0000 steel wool of 10 mm square was used, and the surface of the hard coat layer on the reflective polarizing film was 100 times (cycled) at a load of 250 g, a stroke of 85 mm, and a speed of 60 cycles / minute. ) Or 200 times (cycle). FIG. 7 shows a schematic diagram of a steel wool wear resistance test apparatus 60 (rubbing tester IMC-157C, obtained from Imoto Seisakusho Co., Ltd.). Here, the reflective polarizing film 10 is fixed on the stage 61, the load of the weight 63 is applied to the steel wool 64 through the stylus 62, and the stage 61 is reciprocated to polish the surface of the sample. The steel wool abrasion resistance test simulates scratching when a reflective polarizing film incorporated in a liquid crystal display comes into contact with a prism film.

  The degree of surface change was evaluated visually in three stages: “no scratch”, “no significant scratch”, and “noticeable scratch” that cannot be used as a reflective polarizing film.

2. Optical properties The optical properties (effective transmittance and color shift) of the reflective polarizing film were measured using an ET test apparatus (manufactured by 3M Company). “Effective transmittance” is the ratio of the luminance of the component transmitted through the polarizing plate in the light emitted from the light source (backlight), and is defined as the ratio of the luminance when the sample is used and the luminance when the sample is not used. The “Color shift” is the change in the color of the component transmitted through the polarizing plate in the light emitted from the light source (backlight), and is defined as the amount of change in color when the sample is used and when not used. The

  FIG. 8 shows a schematic diagram of the configuration of the ET test apparatus 80. Light emitted from a lamp (not shown) of the light source device 84 via the optical fiber 85 enters the light box 83, and light scattered through a diffusion plate (not shown) provided on the upper side of the light box is reflected. Incident on the polarizing film 10. The luminance and color of the light transmitted through the reflective polarizing film 10 and the polarizing unit 82 are measured by the spectrocolorimeter 81. Details of the equipment and test procedure are as follows.

Sample: 76.2 mm × 127 mm (3 inches × 5 inches), 0 degree bias Spectrocolorimeter: PR-650 (or equivalent) manufactured by Photosearch
Polarization unit: P / N 03FPG007 (or equivalent) manufactured by Melles Griot, single unit transmittance 32%, parallel Nicol transmittance ≧ 20%
Light box: 6.35 mm thick Teflon (registered trademark) diffusion plate Direct type light box Light source device: DCR II w manufactured by Fostec
Lamp: EKE 21V150W
Apparatus: Spectra Colorimeter (available from Model PR-650, Spectra Scan, Photo Research Inc.)
Procedure: A sample of a reflective polarizing film that had been hard-coated was placed on a Teflon (registered trademark) diffusion plate of a light box, and the luminance and color were measured.

  The reagents and raw materials used in this example are shown in Table 1 below.

<Preparation of surface-modified silica sol (sol 1)>
A surface-modified silica sol (“sol 1”) was prepared as follows. 5.95 g SILQUEST A174 and 0.5 g PROSTAB were added to a mixture of 400 g NALCO 2329 and 450 g 1-methoxy-2-propanol in a glass bottle and stirred for 10 minutes at room temperature. The glass bottle was sealed and placed in an 80 ° C. oven for 16 hours. Water was removed from the resulting solution with a rotary evaporator at 60 ° C. until the solid content of the solution was close to 45% by mass. 200 g of 1-methoxy-2-propanol was added to the resulting solution and then the remaining water was removed using a rotary evaporator at 60 ° C. The latter step was repeated twice to remove more water from the solution. Finally, the SiO ₂ sol containing surface-modified SiO ₂ nanoparticles with an average particle size of 75 nm, with the addition of 1-methoxy-2-propanol to adjust the concentration of all SiO ₂ nanoparticles to 45% by weight. (Hereinafter referred to as sol 1).

<Preparation of surface-modified silica sol (sol 2)>
A surface-modified silica sol (“sol 2”) was prepared as follows. Surface modified SiO ₂ nanoparticles with an average particle size of 20 nm were modified in the same manner as sol 1 except that 400 g NALCO 2327, 25.25 g SILQUEST A174 and 0.5 g PROSTAB were used. An SiO ₂ sol containing 45% by mass (hereinafter referred to as sol 2) was obtained.

<Preparation of hard coat precursor (HC)>
108.33 g of sol 1, 58.33 g of sol 2, and 25.0 g of Kayrad UX-5000 were mixed. 2.00 g of Irgacure 2959 as a photopolymerization initiator, 0.01 g of BYK-UV3500 as a leveling agent, and 2.50 g of KY-1203 as an antifouling agent were added to the mixture. Next, 1-methoxy-2-propanol was added to adjust the solid content to 50.1% by mass to prepare a hard coat precursor HC.

  The composition of HC is shown in Table 2.

<Example 1>
The hard coat precursor HC was applied to the back surface of an advanced polarizer film (APF, reflective polarizing film, obtained from 3M Company) using a Mayer rod # 4, and dried at 60 ° C. for 5 minutes. Next, Fusion UV System Inc. The H-bulb (DRS model) was used to irradiate the coated surface with ultraviolet rays (UV-A) at an illuminance of 900 mW / cm ² in a nitrogen atmosphere. The thickness of the hard coat layer was 1.2 μm. In this way, a reflective polarizing film having a hard coat layer was prepared.

<Example 2>
A reflective polarizing film having a hard coat layer was prepared in the same procedure as in Example 1 except that the Mayer rod # 8 was used. The thickness of the hard coat layer was 3.5 μm.

<Comparative Example 1>
A sample obtained by subjecting the APF to no hard coat treatment was prepared as Comparative Example 1.

  The results of evaluating these reflective polarizing films are shown in Table 3.

DESCRIPTION OF SYMBOLS 10 Reflective polarizing film 12 Reflective polarizing layer 14, 24, 34 Hard coat layer 16 Absorption polarizing layer 18 Adhesive layer 20 Prism film 22, 22A, 22B Prism layer 26 Composite optical film 32, 32A, 32B Diffusion layer 36 Light guide plate 38 reflector 42 light source 44 liquid crystal display panel 46 control device 50, 52, 54 liquid crystal display 60 steel wool wear resistance test device 61 stage 62 stylus 63 weight 64 steel wool 80 ET test device 81 spectrocolorimeter 82 polarization unit 83 light box 84 Light source device 85 Optical fiber

Claims (7)

An optical component comprising: an optical functional layer having a first surface; and a hard coat layer disposed on the first surface of the optical functional layer, wherein the hard coat layer comprises a mixture of nanoparticles and a binder ,
The nanoparticles constitute 40% by mass to 95% by mass of the total mass of the hard coat layer,
10% to 50% by weight of the nanoparticles have an average particle size in the range of 2 nm to 200 nm, 50% to 90% by weight of the nanoparticles have an average particle size in the range of 60 nm to 400 nm, The ratio of the average particle size of nanoparticles having an average particle size in the range of 60 nm to 400 nm and the average particle size of nanoparticles having an average particle size in the range of 2 nm to 200 nm is in the range of 2: 1 to 200: 1. , Optical components.   The optical component according to claim 1, wherein the optical functional layer is selected from the group consisting of a reflective polarizing layer, an absorbing polarizing layer, a diffusing layer, and a prism layer having a prism structured surface.   The optical component according to claim 1, wherein the nanoparticles include surface-modified nanoparticles.   The optical component according to any one of claims 1 to 3, wherein the binder includes a fluorinated (meth) acrylic compound, a reaction product thereof, or a combination thereof.   A light management unit comprising the optical component according to claim 1 and a prism film having a prism structured surface, wherein the hard coat layer faces the prism structured surface. , Light management unit.   A backlight assembly comprising a light source and the light management unit according to claim 5.   A display comprising a light source, a liquid crystal display panel, and the light management unit according to claim 5.

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