KR20170022895A - Composition for light guiding plate, light guiding plate and method for producing the same, and edge-light type surface emitting apparatus - Google Patents

Abstract

Provided is a composition for a light guide plate for producing a light guide plate, which suppresses luminance unevenness and can efficiently output light suppressing the degree of yellow to a light output surface side of a light guide substrate. The composition for a light guide plate according to the present invention comprises: light diffusion particle(A); and a phosphoric acid ester (B), wherein the phosphoric ester (B) has a polymerizable functional group.

Description

TECHNICAL FIELD [0001] The present invention relates to a composition for a light guide plate, a light guide plate, a method for producing the same, and an edge light type surface emitting device.

The present invention relates to a composition for a light guide plate, and more particularly to a light guide plate suitable for an edge light type surface light emitting device and a manufacturing method thereof.

A surface light emitting device used for a liquid crystal display panel or a signboard is a direct type in which a light source is disposed in a planar form to form surface uniform light emission by a diffusion plate or the like and an edge light type in which a light source is disposed on an end face of a light guide plate It is known.

The edge light type surface light emitting device has a light source and a light guide plate. The light guide plate includes a light guiding plate and a light diffusing portion. Light from the light source propagates inside the light guiding plate, and is emitted in a plane by a light diffusing portion disposed on the surface of the light guiding plate. Such a light guide plate is manufactured by applying a composition for a light guide plate containing light diffusing particles to a light guide substrate as described in Patent Documents 1 to 4, and fabricating a light diffusion portion.

Japanese Patent Application Laid-Open No. 09-145937 Japanese Unexamined Patent Application Publication No. 146771 Japanese Patent Application Laid-Open No. H02-216528 Japanese Patent Laid-Open Publication No. 1-178345

Such a surface light emitting device is required to be further improved in energy efficiency, and a technique for sufficiently extracting the light supplied from the light source to the light guide substrate toward the light output surface side of the light guide substrate is required.

The present invention has been made in order to solve the problems in the conventional art as described above. Some embodiments of the present invention provide a composition for a light guide plate for producing a light guide plate capable of suppressing unevenness in brightness and capable of efficiently emitting light whose degree of yellow is suppressed to the light exit surface side of the light guide plate.

In addition, some embodiments according to the present invention provide a light guide plate capable of suppressing luminance unevenness and capable of efficiently emitting light with suppressed degree of yellow, a method of manufacturing the same, and an edge type surface light emitting device provided with the light guide plate.

The present invention has been made to solve at least a part of the above-mentioned problems, and can be realized as the following aspects or applications.

[Application Example 1]

In one form of the composition for a light guide plate according to the present invention,

The light-diffusing particles (A)

Phosphoric acid ester (B)

And the phosphate ester (B) has a polymerizable functional group.

[Application example 2]

In the composition for a light guide plate of Application Example 1,

Further comprises a photopolymerizable component (C)

Mb / (Mb + Mc) = 0.001 to 0.06 when the content of the phosphate ester (B) is Mb (mass part) and the content of the photopolymerizable component (C) is Mc (mass part).

[Application Example 3]

In the composition for a light guide plate of Application Example 1 or Application Example 2,

The phosphoric acid ester (B) may be a compound represented by the following general formula (1).

(In the general formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a divalent organic group, and n represents an integer of 1 or 2)

[Application example 4]

In the composition for a light guide plate according to any one of Application Examples 1 to 3,

And may further contain a hydroquinone derivative.

[Application Example 5]

In the composition for a light guide plate according to any one of Application Examples 1 to 4,

And may further contain a colorant (D).

[Application Example 6]

In the composition for a light guide plate of Application Example 5,

(D) may be contained in an amount of 0.01 × 10 ^-4 to 10 × 10 ^-4 parts by mass based on 100 parts by mass of the light-diffusing particles (A).

[Application Example 7]

In the composition for a light guide plate of Application Example 5 or Application Example 6,

The colorant (D) may be a blueing agent.

[Application Example 8]

In one form of the light guide plate according to the present invention,

A light guide plate comprising a light-guiding substrate and a light diffusion portion,

Wherein the value of the surface roughness Ra of the light-guiding substrate is Ra < 1 nm,

Wherein the light diffusing portion contains light diffusing particles (A) having an average particle diameter D (nm)

200 < D / Ra < 5000.

[Application Example 9]

According to an aspect of a method of manufacturing a light guide plate according to the present invention,

A method for manufacturing a light guide plate including a light guiding plate and a light diffusion portion,

On the light guide substrate having a surface roughness Ra of Ra < 1 nm,

The light diffusing portion is manufactured by applying the composition for a light guide plate of any one of Application Examples 1 to 7, which contains light diffusing particles (A) having an average particle diameter D (nm) and 200 <D / Ra < .

[Application Example 10]

According to an aspect of the edge light type surface light emitting device according to the present invention,

And a light guide plate of Application Example 8 is provided.

According to the present invention, it is possible to manufacture a light guide plate capable of suppressing unevenness of brightness and emitting light with reduced degree of yellow efficiently to the light exit surface side by applying the composition to the light guide plate to form a light diffusion portion. Further, according to the present invention, there is provided a light guide plate capable of suppressing luminance unevenness and capable of efficiently emitting light with suppressed degree of yellow color, a method of manufacturing the same, and an edge type surface light emitting device provided with the light guide plate.

1 is a schematic cross-sectional view showing an example of an edge light type surface emitting device.
2 is a plan view of the side of the light guide plate on which the light diffusion portion is formed.

Hereinafter, preferred embodiments according to the present invention will be described in detail. It is to be understood that the present invention is not limited to the following embodiments, but includes various modifications embodying the invention without departing from the gist of the invention. The term "(meth) acrylic acid" in the present specification covers both of "acrylic acid" and "methacrylic acid". The term &quot; (meth) acrylate &quot; is a concept covering both of &quot; acrylate &quot; and &quot; methacrylate &quot;. The term "(meth) allyl" is a concept encompassing both "allyl" and "methallyl".

1. Composition for a light guide plate

The composition for a light guide plate is a composition used for manufacturing a light diffusion portion of a light guide plate. One form of the composition for a light guide plate according to the present embodiment contains light diffusing particles (A) and phosphoric acid ester (B), and the phosphoric ester (B) has a polymerizable functional group.

Hereinafter, the components of the composition for a light guide plate will be described in detail.

1.1. The light-diffusing particles (A)

As the light-diffusing particles (A), inorganic particles or organic particles can be used. As the inorganic particles, calcium carbonate particles, barium sulfate particles, titanium dioxide particles and the like can be preferably used. As the organic particles, core-shell type organic particles, hollow organic particles, and non-spherical shaped, dissimilar organic particles are preferable. The light-diffusing particles (A) used in the present invention can be used singly or in combination of two or more kinds.

The average particle diameter D (cumulative 50% particle diameter D50) of such light diffusing particles (A) is preferably 200 to 5000 nm, more preferably 300 to 4000 nm. The inorganic particles having a particle diameter D50 falling within the above range can be obtained by appropriately selecting them based on the particle size distribution from a commercial product. The core shell particles, the organic particles, the releasing particles and the like can be produced by the method described in International Publication No. 2005/071014 or Japanese Patent Laid-Open Publication No. 2013-93205.

It is preferable that the absolute value of refractive index difference |? N | between the light-diffusing particle (A) and the photopolymerizable component described below after polymerization is 0.02? |? N |? 1.3. For example, when a photopolymerizable monomer having no hydroxyl group or a photopolymerizable oligomer is used as the photopolymerizable component, calcium carbonate particles (refractive index: n = 1.59) and barium sulfate particles (refractive index: n = 1.64) and titanium dioxide particles (refractive index: n = 2.7) are used.

In 100 parts by mass of the composition for a light guide plate, the content of the light-diffusing particles (A) is preferably 0.5 to 30 parts by mass. The content of the light-diffusing particles (A) in the composition for a light guide plate is preferably 0.5 to 30% by mass based on the total mass of the composition for a light guide plate.

1.2. Phosphoric ester (B)

The phosphoric acid ester (B) used in the present invention is not particularly limited as long as it has a polymerizable functional group, and may be radical polymerizable or cationic polymerizable. The phosphate ester (B) used in the present invention is preferably a phosphate ester represented by the following general formula (1). When the phosphoric acid ester (B) is photopolymerizable, in the present invention, the phosphoric acid ester (B) and the photopolymerizable component (C) described later are treated as different components.

(In the general formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a divalent organic group, and n represents an integer of 1 or 2)

The phosphoric ester (B) is suitably used to improve balance between hardness, scratch resistance, abrasion resistance and low curl performance when a composition for a light guide plate is used as a cured coating film.

In the general formula (1), R ² is a divalent organic group, preferably a divalent hydrocarbon group, and is preferably a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms.

Examples of the phosphoric acid ester (B) used in the present invention include mono or bis (2- (meth) acryloyloxyethyl) acid phosphate, mono or bis (2- (meth) acryloyloxypropyl) , Mono- or bis (3- (meth) acryloyloxypropyl) acid phosphate, mono- or bis (6- (meth) acryloyloxyhexyl) acid phosphate, mono- or bis (1-chloromethyl-2- (meth) acryloyloxyethyl) acid phosphate, 2-methacryloyloxyethylphenyl acid phosphate, etc., and lactone-modified products thereof, polyoxy Alkylene-modified products, and the like. Among them, mono or bis (2- (meth) acryloyloxyethyl) acid phosphate is preferable from the viewpoint of obtaining a cured product having high hardness. The phosphoric acid esters (B) used in the present invention may be used singly or in combination of two or more.

Examples of the phosphoric acid ester (B) include trade names: LIGHT ESTER P-1M, P-2M, KAYAMER PM-2 manufactured by Kyoeisha Chemical Co., , PM-21 and the like can be used.

In 100 parts by mass of the composition for a light guide plate, the content Mb of the phosphoric acid ester (B) is preferably 0.07 to 5 parts by mass, more preferably 0.2 to 2 parts by mass. The content of the phosphoric acid ester (B) in the composition for a light guide plate is preferably 0.07 to 5 mass%, more preferably 0.2 to 2 mass%, based on the total mass of the composition for a light guide plate. When the content of the phosphoric acid ester (B) is within the above range, the adhesion of the light diffusion part made of the composition for a light guide plate according to the present invention can be improved.

1.3. The photopolymerizable component (C)

When a light diffusing portion is produced by using a composition for a light curing type light guide plate, the photopolymerizable component is preferably a radically polymerizable component, more preferably a photopolymerizable functional group such as a vinyl group. As the photopolymerizable component (C), for example, a photopolymerizable monomer or a photopolymerizable polymer can be used. As specific examples of such photopolymerizable component (C), for example, compounds described in International Publication No. 2005/071014 or Japanese Patent Laid-Open Publication No. 2013-93205 can be used timely.

As the photopolymerizable monomer, for example, a vinyl aromatic compound, an unsaturated nitrile, a (meth) acrylic acid ester, an unsaturated carboxylic acid ester, and an unsaturated amide can be used.

Examples of the vinylaromatic compound include styrene,? -Methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-tert-butylstyrene, divinylbenzene, diisopropenylbenzene, -Chlorostyrene, 1,1-diphenylethylene, p-methoxystyrene, N, N-dimethyl-p-aminostyrene, N, N-diethyl- Can be used.

Examples of the unsaturated nitrile include (meth) acrylonitrile,? -Chloroacrylonitrile,? -Chloromethylacrylonitrile,? -Methoxyacrylonitrile,? -Ethoxyacrylonitrile, crotonic acid nitrile, Itaconitrile, itaconic acid dinitrile, maleic acid dinitrile, fumaric acid dinitrile, and the like.

Examples of the (meth) acrylic esters include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, (Meth) acrylate, n-octyl (meth) acrylate, sec-butyl (meth) acrylate, tert- (Meth) acrylate, stearyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2- ethoxyethyl (Meth) acrylate;

(Meth) acrylate esters having a hydroxyl group such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and 3-hydroxypropyl (meth) acrylate; (Meth) acrylic acid monoesters of polyalkylene glycols such as polyethylene glycol and polypropylene glycol;

Cyano group-containing (meth) acrylate esters such as cyanoethyl (meth) acrylate and cyanopropyl (meth) acrylate; (Meth) acrylic acid aryloxyalkyl esters such as 2-phenoxyethyl (meth) acrylate, 2-phenoxypropyl (meth) acrylate and 3-phenoxypropyl (meth) acrylate;

(Meth) acrylic acid monoesters of alkoxypolyalkylene glycols such as methoxypolyethylene glycol, ethoxypolyethylene glycol, methoxypolypropylene glycol and ethoxypolypropylene glycol; (Meth) acrylic acid monoesters of aryloxypolyalkylene glycols such as phenoxypolyethylene glycol and phenoxypolypropylene glycol; (Meth) acrylic acid diesters of alkylene glycols such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol and neopentyl glycol;

(Meth) acrylic acid diester of a polyalkylene glycol (the number of alkylene glycol units is, for example, 2 to 23) such as polyethylene glycol, polypropylene glycol and the like, a terminal hydroxypolybutadiene, a terminal hydroxypolyisoprene, (Meth) acrylic acid diesters of polymers having hydroxyl groups at both terminals, such as terminal hydroxybutadiene-acrylonitrile copolymer and both terminal hydroxypolycaprolactone;

Glycerin, 1,2,4-butanetriol, trimethylolalkane (the number of carbon atoms of the alkane is, for example, 1 to 3), tetramethylolalkane (the number of carbon atoms of the alkane is, for example, 1 to 3), pentaerythritol (Meth) acrylic acid diesters such as trihydric or higher polyhydric alcohols such as (meth) acrylic acid triester or (meth) acrylic acid tetraester;

(Meth) acrylic acid triesters of polyalkylene glycol adducts of polyhydric alcohols having three or more hydroxyl groups, (meth) acrylic acid oligo esters such as (meth) acrylic acid tetraesters; Etc. may be used.

Specific examples of the unsaturated carboxylic acid esters include unsaturated carboxylic acid esters such as methyl crotonate, ethyl crotonate, propyl crotonate, butyl crotonate, methyl cinnamate, ethyl cinnamate, propyl cinnamate, Can be used.

Specific examples of the unsaturated amide include unsaturated amides such as (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, N- (2-hydroxyethyl) (meth) acrylamide, N, N- (Meth) acrylamide, N, N'-methylenebis (meth) acrylamide, N, N'-ethylenebis , And unsaturated amides such as cinnamic acid amide and the like.

As the photopolymerizable polymer, any known photopolymerizable polymer can be used as long as it has a photopolymerizable group introduced into the polymer backbone, but it is preferably a radical polymerizable polymer. The polymer skeleton of such a photopolymerizable polymer includes a polyethylene skeleton, a polyurethane skeleton, a polyester skeleton, a polyamide skeleton, a polyimide skeleton, a polyoxyalkylene skeleton, and a polyphenylene skeleton, and preferably a polyethylene skeleton, It is a polyurethane skeleton. Examples of the photopolymerizable group include (meth) acryloyl groups, alkenyl groups, cinnamoyl groups, cinnamylidene acetyl groups, benzalacetophenone groups, styrylpyridine groups,? -Phenylmaleimide groups, A benzoquinone group, a stilbene group, a dithiocarbamate group, a thiophene group, a dithiocarbamate group, a thiophene group, a thiophene group, (Meth) acryloyl group and a cinnamoyl group, and particularly preferably a (meth) acryloyl group and a cinnamoyl group, and particularly preferably a (Meth) acryloyl group.

In the case where the composition for a light guide plate contains a photopolymerizable component (C), the content Mc of the photopolymerizable component (C) in the 100 parts by mass of the composition for a light guide plate is preferably 50 to 95 parts by mass, more preferably 65 to 80 parts by mass Do. The content of the photopolymerizable component (C) in the composition for a light guide plate is preferably 50 to 95 mass%, more preferably 65 to 80 mass%, based on the total mass of the composition for a light guide plate. When the content ratio of the photopolymerizable component (C) is within the above range, the light diffusion particles (A) contained in the light diffusion portion manufactured using the composition for a light guide plate according to the present embodiment can be maintained at a sufficient strength, It is possible to effectively prevent the light diffusion particles (A) from being peeled off and generating foreign matter.

When the composition for a light guide plate contains a photopolymerizable component (C), when the content of the phosphoric acid ester (B) is Mb (mass part) and the content of the photopolymerizable component (C) is Mc (mass part) (Mb + Mc) = 0.001 to 0.1, more preferably Mb / (Mb + Mc) = 0.001 to 0.06, and Mb / (Mb + Mc) = 0.005 to 0.06 desirable. When the value of Mb / (Mb + Mc) is within the above range, the light extraction efficiency of the light diffusion portion manufactured using the composition for a light guide plate according to the present embodiment can be improved.

1.4. The colorant (D)

The composition for a light guide plate according to the present embodiment may contain a colorant (D). The colorant (D) is preferably a blueing agent. The "blueing agent" in the present invention is a component that adjusts color by absorbing light in a wavelength region such as orange to yellow in the visible light region.

When the light-guiding substrate is a resin substrate, the resin substrate tends to absorb light in the blue wavelength region among the light emitted from the light source. For this reason, the light intensity of the blue wavelength region decreases with the light guided in the light guide substrate for a longer period of time. As a result, in the light diffusing portion remote from the light source, light that has passed through the light guide substrate for a longer time reaches, so that yellowish light tends to be emitted. Therefore, by using a light diffusing section including a coloring agent such as a bluing agent, it becomes possible to cancel the change in such color tone.

As the bluing agent, a dye and a pigment are preferable, and examples thereof include inorganic dyes and pigments such as ultramarine blue, persimmon blue and cobalt blue, phthalocyanine blueing agents, condensed polycyclic blueing agents (for example, indigo blueing agents, anthraquinone blue And organic pigments and pigments such as a pigment and an ink. Of these, condensed polycyclic blueing agents are preferred, and anthraquinone-based bluing agents are more preferred.

As the anthraquinone type blueing agent, a blueing agent containing an anthraquinone ring represented by the following formula (2), a compound represented by the following formula (3), and the like can be used.

Such anthraquinone-based blueing agents are also commercially available and include, for example, Plast Blue 8510, Plast Blue 8514, Plast Blue 8516, Plast Blue, 8520, Plast Blue 8540, Plast Blue 8580 and Plast Blue 8590 (all of which are manufactured by Arimoto Kagaku Kogyo Co., Ltd.), Macrolux Violet B, Macrolux Violet 3R, Macrolux blue RR (all manufactured by Bayer), Dia Resin Blue B, Dia Resin Violet D, Dia Resin Blue J, Dia Resin Blue N and Dia Resin Blue G (all manufactured by Mitsubishi Kagaku) Plast Violet B (manufactured by Sumitomo Chemical Co., Ltd.), tetrazole blue RLS (manufactured by Sand), and the like. The colorant (D) used in the present invention may be used alone or in combination of two or more.

Of these commercially available blueing agents, Plast Blue 8510, Plast Blue 8514, Plast Blue 8516, Plast Blue 8520, Plast Blue 8516, ) 8540, Plast Blue 8580, Plast Blue 8590 are preferable, and Plast Blue 8514 is particularly preferable.

The content of the coloring agent (D) in the composition for light guide plate according to the present embodiment, the light diffusing particle (A) relative to 100 parts by mass of 0.01 × 10 ^-4 to 10 × 10 ^{- 4} parts by mass denied preferably, 0.1 × 10 ^-4 to 1 × 10 ^- is more preferably ⁴ parts by mass. When the content ratio of the colorant (D) is within the above range, the adhesiveness of the light diffusion portion manufactured using the composition for a light guide plate according to the present embodiment can be improved.

1.5. Photopolymerization initiator

When a light diffusing portion is produced by using a composition for a light curing type light guide plate, the photopolymerization initiator can be appropriately selected from those conventionally used in the field of ultraviolet curable resins. As the photopolymerization initiator, the compounds described in International Publication No. 2005/071014 or Japanese Patent Laid-Open Publication No. 2013-93205 can be timely used.

Examples of the photopolymerization initiator include? -Diketone compounds such as diacetyl, methylbenzoylformate and benzyl; Benzoin, pivaloin and the like; Acyloin ethers such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether and benzoin isobutyl ether; Polynuclear quinones such as anthraquinone, 2-ethyl anthraquinone, 2-tert-butyl anthraquinone, and 1,4-naphthoquinone; Acetophenone, 2-hydroxy-2-methyl-propiophenone, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxyphenylacetophenone, 2,2-diethoxyacetophenone and trichloroacetophenone Acetophenones; Benzophenones such as benzophenone, methyl-o-benzoyl benzoate and Michler's ketone; Xanthone, thioxanthone, and 2-chlorothioxanthone.

When the composition for a light guide plate contains a photopolymerization initiator, the content of the photopolymerization initiator in the 100 parts by mass of the composition for a light guide plate is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass. The content of the photopolymerization initiator in the composition for the light guide plate is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass.

1.6. Other components

The composition for a light guide plate according to the present embodiment may contain components other than the light diffusion particles (A), the phosphoric acid ester (B), the photopolymerizable component (C), the colorant (D) and the photopolymerization initiator. For example, by using an aliphatic urethane (meth) acrylate or the like, the viscosity and photo-curability of the composition for a light guide plate can be controlled, and the surface tension of the composition for a light guide plate and the wettability Can be controlled. Also, by using the binder described in International Publication No. 2005/071014 or Japanese Patent Laid-Open Publication No. 2013-93205, a light diffusion portion having improved mechanical strength such as adhesion can be manufactured.

The composition for a light guide plate according to the present embodiment preferably contains a hydroquinone derivative. Examples of the hydroquinone derivatives include hydroquinone derivatives such as hydroquinone, hydroquinone monomethyl ether, mono-tert-butylhydroquinone, catechol, p-tert-butyl catechol, p- Hydroxyaromatic compounds such as di-tert-butylhydroquinone, 2,6-di-tert-butyl-m-cresol, pyrogallol and? -Naphthol, benzoquinone, 2,5-diphenyl-p-benzoquinone, p -Toluoquinone, p-xyloquinone or the like is preferably used.

When the composition for a light guide plate contains a hydroquinone derivative, the content of the hydroquinone derivative in the 100 parts by mass of the composition for a light guide plate is preferably 0.001 to 2 parts by mass, more preferably 0.01 to 1 part by mass. The content of the hydroquinone derivative in the composition for a light guide plate is preferably 0.001 to 2 mass%, more preferably 0.01 to 1 mass%, based on the total mass of the composition for a light guide plate. When the content of the hydroquinone derivative is within the above range, the whiteness of the light diffusion portion manufactured using the composition for a light guide plate according to the present embodiment can be further improved. Further, the hydroquinone derivative is generally known as a storage stabilizer (polymerization inhibitor). However, in the case of nitrosoamine metal salts such as N-nitrosophenylhydroxylamine aluminum salt generally used as the similar storage stabilizer, it is sometimes difficult to further improve the whiteness such as yellowing of the light diffusing portion.

2. Light guide plate and manufacturing method thereof

The light guide plate according to the present embodiment includes a light guide plate and a light diffusing portion, wherein the surface roughness Ra of the light guiding plate has a value of Ra <1 nm and the light diffusing portion has light diffusing particles having an average particle diameter D (nm) A), and 200 < D / Ra < 5000.

The method for manufacturing a light guide plate according to the present embodiment is a method for manufacturing a light guide plate including a light guide substrate having a surface roughness Ra of Ra <1 nm and light diffusing particles A having an average particle diameter D (nm) 5,000, and the light diffusing portion is fabricated by applying the composition for a light guide plate described above.

1 is a cross-sectional view showing a transmissive image display apparatus including an embodiment of a light guide plate according to the present invention. The transmission type image display apparatus 100 shown in Fig. 1 is mainly composed of a surface light source device 20 and a transmission type image display section 30. Fig. The planar light source device 20 includes a light guide plate 1 having a light guiding substrate 11 and a light diffusion portion 12 and a light source provided on a side of the light guide plate 1 for supplying light to the light guide plate 1 3). In the edge light type surface light source device shown in Fig. 1, the light diffusion portion 12 has a plurality of dot shapes.

The light guiding substrate 11 has a substantially rectangular parallelepiped shape and has an emission surface S1, an emission surface S2 on the opposite side of the emission surface S1, and four end surfaces S3 ₁ to S3 ₄ intersecting the emission surface S1 and the emission surface S2 . In the present embodiment, the four end faces S3 ₁ to S3 ₄ are substantially orthogonal to the emission face S1 and the emission face S2.

The light guide plate 1 further includes a plurality of light diffusing portions 12 provided on the side of the emitting surface S2. As shown in Fig. 2, the plurality of light diffusing portions 12 are arranged on the emission surface S2 so as to be spaced apart from each other. Fig. 2 is a plan view of the light-guiding substrate when viewed from the side of the exit surface S2. In Fig. 2, the light source 3 is also shown for convenience of explanation. In Fig. 2, the light diffusion portions 12 are disposed apart from each other. The number and arrangement pattern of the light diffusion portions 12 are adjusted so that light on a uniform plane is efficiently emitted from the emission surface S1 and, if necessary, from the emission surface S2.

As shown in Figs. 1 and 2, the light source 3 is disposed on either side of the pair of end faces S3 ₁ , S3 ₂ facing each other, or on the side of S3 ₁ , S3 ₂ . As shown in Fig. 2, for example, a plurality of point light sources may be arranged along two sides or one side of the four sides constituting the rectangular emitting surface S2 of the light-guiding substrate 11 .

In the above configuration, light output from the light source 3 is incident on the light guide substrate 11 from the end faces S3 ₁ and S3 ₂ . The light incident on the light guiding substrate 11 is irregularly reflected by the light diffusing portion 12 and the shape of the light diffusing portion 12 can be adjusted so that light on a uniform surface is efficiently emitted from the emission surface S1 and the emission surface S2 have. For example, in the case of Fig. 1, the light emitted from the emitting surface S1 is supplied to the transmissive-type image display section 30. Fig.

Hereinafter, the members constituting the light guide plate and the manufacturing method of the light guide plate will be described in detail.

2.1. Light-

The light guide plate (1) has a light guiding plate (11). The surface roughness Ra of the light-guiding substrate 11 is preferably Ra <1 nm considering the light extraction efficiency from the exit surface S1 and the exit surface S2, and preferably Ra <0.5 nm. In consideration of the adhesion between the light diffusing portion and a light-guiding substrate described later, Ra> 0.1 nm is preferable, and Ra> 0.2 nm is more preferable.

The surface roughness Ra of the end face of the light guiding substrate 11 is set such that light that can be practically used when the light from the light source is 2 mu m or less is emitted from the light source to the light guiding substrate 11 As shown in FIG.

The "surface roughness Ra" of the light-guiding substrate 11 in the present invention means "arithmetic average roughness" measured in accordance with JIS B0601-2001.

Generally, in the edge light type surface light emitting device, when light is generated from a light source, heat is generated, and accordingly, the temperature of the light guiding substrate rises. In the case of using a resin plate as the light-guiding substrate, since the thermal expansion coefficient of the resin plate is high, the dimensional change due to heat of the light-guiding substrate becomes larger than the dimensional change of the liquid crystal panel. However, due to the narrowing of the frame of the liquid crystal display device, it is difficult to correct the dimensional change of the light-guiding substrate in the frame portion of the liquid crystal display device. For this reason, as the material of the light-guiding substrate 11, a resin plate having small dimensional change due to heat may be used, but a glass substrate is preferable. When the light-guiding substrate 11 is a glass substrate, the maximum transmittance of the glass substrate at an optical path length of 100 mm and a wavelength range of 350 to 750 nm is preferably 50% or more.

The coefficient of thermal expansion of the light-guiding substrate 11 is preferably 120 x 10 &lt; ^-7 &gt; / DEG C or less. When the coefficient of thermal expansion exceeds the above range, the difference in dimensional change due to heat between the display panel and the light guide substrate tends to increase. The deformation point of the light-guiding substrate 11 is preferably 550 DEG C or higher. If the deformation point is less than the above range, the heat resistance of the light-guiding substrate 11 tends to deteriorate. For example, when a reflective film, a diffusion film, or the like is formed on the surface of the light-guiding substrate 11 at a high temperature, . Here, the &quot; strain point &quot; can be measured based on JIS R3103.

2.1.1. Glass composition

As the glass composition constituting the glass substrate, SiO ₂ of 40 to 70 mass%, Al ₂ O ₃ 2 to 25 mass%, B ₂ O ₃ 0 to 20% by weight, R ₂ O (R is Li, Na, 0 to 10 mass% of MgO, 0 to 15 mass% of CaO, 0 to 10 mass% of SrO, 0 to 15 mass% of BaO, and 0 to 10 mass% of ZnO, 0 to 10% by mass, preferably contains from 0 to 10% by weight of ZrO _2.

SiO ₂ is a component that becomes a network former of glass, and is a component that reduces thermal expansion coefficient and reduces dimensional change caused by heat. It is also a component that increases acid resistance and strain point. When the content of SiO ₂ is increased, the high-temperature viscosity is increased and the meltability is lowered, and the cristobalite siltite is likely to precipitate at the time of molding. On the other hand, if the content of SiO ₂ is decreased, the coefficient of thermal expansion increases, and the dimensional change due to heat tends to increase. Also, acid resistance and strain points are likely to be lowered.

Al ₂ O ₃ is a component that reduces the coefficient of thermal expansion and reduces the dimensional change due to heat. It also has the effect of increasing the strain point or inhibiting the precipitation of cristobalite in molding. When the content of Al ₂ O ₃ is within the above range, the liquid phase temperature rises and it becomes difficult to form the glass substrate. On the other hand, when the content of Al ₂ O ₃ is decreased, the coefficient of thermal expansion is increased and the dimensional change due to heat tends to increase. And the strain point is likely to be lowered.

B ₂ O ₃ is a component which acts as a flux and improves the meltability by lowering the high temperature viscosity. It is also a component that reduces the thermal expansion coefficient and reduces the dimensional change caused by heat. When the content of B ₂ O ₃ is within the above range, the dimensional change due to heat can be suppressed and the meltability can be improved and the workability can be improved.

R ₂ O is a component that lowers the high temperature viscosity and improves the meltability. When the content of R ₂ O is within the above range, the strain point can be improved and the maximum transmittance near the wavelength of 550 nm can be improved.

MgO is a component which improves the melting property by lowering only the high temperature viscosity without lowering the strain point. When the content of MgO is within the above range, it is possible to suppress precipitation of the siltite during molding.

CaO is a component which improves the melting property by lowering only the high-temperature viscosity without lowering the strain point. When the content of CaO is within the above range, precipitation of the siltite during molding can be suppressed.

SrO is a component that enhances chemical resistance and devitrification. When the content of SrO is within the above range, the coefficient of thermal expansion is lowered and the dimensional change due to heat can be suppressed.

BaO is a component that enhances chemical resistance and resistance to devitrification in the same manner as SrO. When the content of BaO is within the above range, the coefficient of thermal expansion is lowered and the dimensional change due to heat can be suppressed.

ZnO is a component that improves the meltability. If the content of ZnO is within the above range, resistance to devitrification can be improved.

ZrO ₂ is a component that increases the strain point. When the content of ZrO ₂ is within the above range, it is possible to suppress deposition of the siltite during molding.

The content of transition metal oxides such as Fe ₂ O ₃ , Cr ₂ O ₃ , V ₂ O ₅ , NiO, MnO ₂ , Nd ₂ O ₃ , CeO ₂ and Er ₂ O ₃ is preferably 0.1 mass% or less. If the content of the transition metal oxide is excessively large, the light extraction efficiency may be lowered.

Other components may be introduced in addition to the above components. For example, in order to lower the liquidus temperature, up to 3 mass% each of Y ₂ O ₃ , La ₂ O ₃ , Nb ₂ O ₅ and P ₂ O ₅ , As ₂ O ₃ , Sb ₂ O ₃ , SnO ₂ , SO ₃ , F, Cl, and the like in a total amount of up to 2% by mass.

2.1.2. Manufacturing method of glass substrate

The glass substrate can be manufactured by an overflow down-draw method, a slot down draw method, a float method, a roll-out method, a lead-down method, or the like. Further, in the float method, the temperature difference and composition difference of the front and back surfaces of the glass ribbon are likely to occur at the time of molding, but if the temperature control during molding is strictly performed, the temperature difference and compositional difference can be reduced. In the overflow down-draw method, the temperature difference and the composition difference between the front and back surfaces of the glass ribbon are difficult to generate at the time of molding, and the glass substrate having a good surface quality with unburned is easily formed.

Further, the glass substrate may be applied to a glass substrate used for a display panel to have the function of the light-guiding substrate. By doing so, the member configuration of the display device can be simplified.

2.2. The light-

The light guide plate 1 according to the present embodiment includes a light diffusing portion 12 containing light diffusing particles (A). The average particle diameter D (nm) of the light-diffusing particles A is preferably in a relationship of 200 <D / Ra <5000 to the surface roughness Ra (nm) of the light-guiding substrate 11, &Lt; 4000 is more preferable. When the value of D / Ra is within the above range, it is possible to suppress the incorporation of voids at the interface between the light guide substrate 11 and the light diffusion portion 12, thereby improving light extraction efficiency and realizing homogeneous surface light emission do.

Fig. 2 is a plan view of the light-guiding substrate 11 when viewed from the side of the emission surface S2. In Fig. 2, the light source 3 is also shown for convenience of explanation. 2, the light diffusion portions 12 are in the form of a plurality of substantially circular dots spaced apart from each other. However, the shape and the like may be adjusted in consideration of the necessary light extraction efficiency from the emission surface S1 and the emission surface S2 . The shape of the light diffusing portion 12 shown in Fig. 2 is for convenience of explanation, and can be adjusted in consideration of the required light extraction efficiency from the exit surface S1 and the exit surface S2.

The light diffusion portion 12 can be manufactured using the composition for a light guide plate described above. The light diffusion portion 12 may be formed on the light guide substrate 11 by a screen printing method, an offset printing method, a spray coating method in which the composition for a light guide plate is sprayed from a nozzle, or the like. For example, the light guide plate can be manufactured by a method described in International Publication Nos. 2005/071014, 2013-93205, 2012-178345, and the like.

As such a composition for a light guide plate, a thermosetting or photo-curable composition for a light guide plate is preferable. In order to effectively suppress the deformation of the light guide substrate by the heat treatment, it is more preferable to fabricate the light diffusion section using the composition for the light guide plate of the light curing type. The composition for a light guide plate for forming the light diffusion portion 12 is preferably a radiation curable composition for a light guide plate containing a photopolymerizable component and a photopolymerization initiator in a photocurable composition for a light guide plate.

It is preferable that the area of the light diffusion portion 12 is 5% or more and 95% or less with respect to 100% of the area of the light guide substrate 11. [ The ratio of the planar area occupied by the light diffusing portion 12 on the coated surface of the light guiding substrate 11 and the applied area of the composition for the light guide plate or the applied area of the light guiding plate composition, It is preferable that the ratio of the coating area to the area of the coating surface of the substrate 11 is increased. Thus, the brightness of the light guide plate can be made substantially uniform.

2.3. Light source

As shown in Figs. 1 and 2, the light source 3 is disposed on the side of the end faces S3 ₁ and S3 ₂ . The light source 3 may be a linear light source such as a cold cathode fluorescent lamp (CCFL), or a point light source such as an LED. In this case, as shown in Fig. 2, a plurality of point light sources are arranged along two opposite sides of four sides constituting the rectangular emitting surface S2 of the light guide plate 11, for example, 12 and the light source 3 are preferably combined.

In the above configuration, light output from the light source 3 is incident on the light guide plate 11 from the end faces S3 ₁ and S3 ₂ . The light incident on the light guide plate 11 is diffused or diffused in the light diffusing portion 12, so that the light is emitted from the exit surface S1 or S2. The light emitted from the emission surface S1 or S2 is supplied to the transmission type image display section 30 or the like. The number of light diffusion portions 12 and the arrangement pattern can be appropriately adjusted so that light on a uniform plane is efficiently emitted from the emission surface.

2.4. The transmissive-type image display section

1, the transmissive-type image display section 30 is arranged opposite to the light guide plate 1 on the light exit surface S1 side of the light guide plate 1, and light emitted from the light exit surface S1 passes through the transmissive image display section 30 ). As the transmissive-type image display section 30, for example, a liquid crystal display section having a liquid crystal cell can be used.

3. Example

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples. In the examples and comparative examples, &quot; part &quot; and &quot;% &quot; are based on mass unless otherwise specified.

3.1. Production of light diffusing particles (A)

3.1.1. Fabrication of hollow particles

109.5 parts of water, 0.2 part of sodium dodecylbenzenesulfonate (trade name: F65, manufactured by Kao Corporation) and 0.5 part of sodium persulfate were fed into a reaction vessel of 2 liter capacity. On the other hand, 90 parts of methyl methacrylate, 10 parts of methacrylic acid, 2.5 parts of octylthioglycol as a molecular weight regulator, 0.1 part of an emulsifier (trade name: F65, manufactured by Kao Corporation) and 40 parts of water were mixed and stirred to prepare an aqueous dispersion Sieve. 20% of the aqueous dispersion of the monomer mixture was charged into the reaction vessel, and the temperature in the reaction vessel was elevated to 75 캜 while stirring the liquid, and the polymerization reaction was conducted for 1 hour. Thereafter, the remaining monomer mixture Was continuously added to the reaction vessel over 2 hours and further aged for 2 hours to obtain an aqueous dispersion of seed particles having a solid content of 40% and a particle diameter of 0.2 탆.

186 parts of water was put into a 2 liter reaction vessel, and 25 parts of the aqueous dispersion of the seed particles and 0.5 part of sodium persulfate were added to the reaction vessel. On the other hand, a mixture of 79.5 parts of methyl methacrylate, 20 parts of methacrylic acid, 0.5 parts of divinylbenzene (purity 81%), 3 parts of octylthioglycol, 0.1 parts of emulsifier (trade name: F65, Followed by mixing and stirring to prepare an aqueous dispersion of the monomer mixture. Next, the liquid in the reaction vessel was heated and maintained at a temperature of 80 DEG C with stirring, and the aqueous dispersion of the monomer mixture was continuously fed into the reaction vessel over 3 hours. Thereafter, aging was further performed for 2 hours to obtain an aqueous dispersion of first polymer particles having a solid content of 31% and a particle diameter of 0.41 탆.

240 parts of water was put in a reaction vessel of 2 liters in capacity, and 48.4 parts of the above-mentioned aqueous dispersion of the first polymer particles, 20 parts of styrene and 0.4 part of sodium persulfate were added, and the temperature in the reaction vessel was raised to 80 deg. , And polymerization of styrene was carried out for 30 minutes to obtain polymer particles in which styrene was incorporated in the first polymer particles. Meanwhile, 56.5 parts of styrene, 3 parts of ethylene glycol dimethacrylate, 0.1 part of an emulsifier (trade name: F65, manufactured by Kao Corporation) and 40 parts of water were mixed and stirred to prepare an aqueous dispersion of a second polymerizable monomer, The liquid in the reaction vessel was maintained at 80 캜 with stirring, and the aqueous dispersion of the second polymerizable monomer was continuously fed into the reaction vessel over a period of 4 hours. At this time, 0.5 parts of acrylic acid was added all at once into the reaction vessel and copolymerized with styrene at 2 hours after the start of charging the aqueous dispersion of the second polymerizable monomer. After all of the aqueous dispersion of the second polymerizable monomer was charged into the reaction vessel, 20 parts of divinylbenzene (purity: 81%) was added thereto in a batch to prepare a first polymer particle having a surface layer of styrene, acrylic acid, To obtain core-shell-shaped polymer particles obtained by polymerizing and laminating acrylate, divinylbenzene. About 15 minutes after the completion of the addition of all the second polymerizable monomers, 5 parts of 20% ammonia aqueous solution was added all at once while stirring was continued, and the temperature was raised to 90 占 폚 and aged for 2 hours with stirring. Thereafter, 0.3 part of t-butyl hydroperoxide and 0.1 part of formaldehyde resin were added and left as it was for 1 hour while stirring to prepare a water dispersion.

The obtained water dispersion was dried using a spray dryer (Pilot series L-12 type) manufactured by Okawara Chemical Industries, Ltd. to obtain a hollow body having a single hole having a particle diameter of 1.1 탆, an inner diameter of 0.9 탆 and a volume vacancy rate of 55% Particles were obtained.

3.1.2. Fabrication of Core Shell Particles

90 parts of styrene and 10 parts of methacrylic acid as a water-soluble initiator were subjected to emulsion polymerization using potassium persulfate to obtain an average of a styrene-derived structural unit and a methacrylic acid-derived structural unit (mass ratio) An aqueous dispersion of seed particles having a particle diameter of 1.0 mu m was prepared.

Next, 2 parts of 3,5,5-trimethylhexanoyl peroxide (product name: Peroil (registered trademark) 355, manufactured by Nichiyu Corporation, water solubility: 0.01%), 0.1 part of sodium lauryl sulfate, and 20 parts of water And the mixture was emulsified with stirring, and then further made into fine particles with an ultrasonic homogenizer (manufactured by Mizuho Kogyo Co., Ltd.) to obtain an aqueous dispersion of a polymerizable monomer. 15 parts of the aqueous dispersion of the seed particles was added to the aqueous dispersion of the prepared polymerizable monomer, and the mixture was stirred for 16 hours. After stirring, 95 parts of styrene and 5 parts of divinylbenzene were added and stirred at 40 占 폚 for 3 hours. Thereafter, the mixture was heated to 75 占 폚 and polymerized for 3 hours to obtain water containing core particles having an average particle diameter of 2.0 占 퐉 The body was obtained.

Next, 22.1 parts of the aqueous dispersion having the same composition as the aqueous dispersion of the polymerizable monomer described above and 40 parts of the core particles described above were mixed and stirred for 16 hours. After stirring, 8 parts of methyl methacrylate and 2 parts of trimethylolpropane trimethacrylate were added and stirred at 40 DEG C for 1 hour. Thereafter, the temperature was raised to 75 DEG C and the polymerization reaction was carried out for 3 hours to coat the surface of the core particles To prepare an aqueous dispersion of core shell particles.

The obtained water dispersion was dried by using a spray dryer (model number "B-290 type", manufactured by Nippon Express Co., Ltd.) to obtain core shell particles having an average particle diameter of 2.2 μm. The thickness of the shell layer was calculated as the difference between the average particle diameter of the core shell particles and the average particle diameter of the core particles, and was 0.2 탆.

3.1.3. Production of dissociated particles

2 parts of t-butyl peroxy-2-ethylhexanoate (trade name "Perbutyl (registered trademark) O", manufactured by Nichiyu Corporation), 0.1 part of sodium lauryl sulfate and 20 parts of water were stirred and emulsified, Further, the mixture was made into fine particles by means of a generizer to obtain an aqueous dispersion. 15 parts of monodisperse polystyrene particles having a number average particle diameter of 1.0 mu m were added to the obtained aqueous dispersion and stirred for 16 hours. Subsequently, 70 parts of styrene, 20 parts of divinylbenzene and 10 parts of 2-hydroxyethyl methacrylate were added and stirred at 40 DEG C for 3 hours. Thereafter, the temperature was raised to 75 DEG C and the polymerization reaction was carried out for 3 hours, To obtain a water dispersion containing the first polymer particles having a diameter of 1.7 탆.

22.1 parts of the same aqueous dispersion as that of the above-mentioned aqueous dispersion and 20 parts of the above-mentioned first polymer particles were mixed and stirred for 16 hours. Subsequently, 90 parts of styrene and 10 parts of divinylbenzene were added, and the mixture was stirred at 40 DEG C for 3 hours. Thereafter, the temperature was raised to 75 DEG C and polymerization was carried out for 3 hours to prepare an aqueous dispersion of dispersed particles.

The obtained water dispersion was dried by using a spray dryer (model number "L-8 type", manufactured by Okawara Chemical Industries, Ltd.) to obtain powdery shaped release particles. The obtained release particles had an average particle diameter of 3.8 mu m, a short diameter of 1.7 mu m and a long diameter of 2.5 mu m.

3.2. Example 1

9.5 parts by mass of calcium carbonate particle A (Brilliant 1500 manufactured by Shiraishi Calcium Co., Ltd.), 15.2 parts by mass of an aliphatic polyurethane acrylate (CN985B88, manufactured by Satomaru Japan Co., Ltd.) as a photopolymerizable oligomer 9.5 parts by mass of isobornyl acrylate (Light Acrylate IBXA, manufactured by Kyoeisha Chemical Co., Ltd.) as a photopolymerizable monomer, 1 part by mass of 1,4-butanediol diacrylate (SR213 ), 4.7 parts by mass of hydroxyhexylphenylethylketone (Irgacure 184, manufactured by BASF Japan Co., Ltd.) as a photopolymerization initiator, phenylbis (2,4,6-trimethylbenzoyl) phosphine oxide 2.8 parts by mass of 4,4 '- [1,10-dioxo-1,10-decanediyl] bis (oxy) bis [2,2,6 , 0.04 part by mass of 6-tetramethyl] -1-piperidinyloxy (Irgas Tab UV10, manufactured by BASF Japan K.K.), 10 parts by mass of a dispersant (Nippon Rubrizol Co., 4.7 parts by mass of a polyvinyl butyral resin (SOLSPERSE 36000), and 0.5 parts by mass of bis (2- (meth) acryloyloxyethyl) phosphate as a phosphate ester (B) A) was dispersed to prepare a composition for a light guide plate containing calcium carbonate particles as the light-diffusing particles (A). The average particle diameter D50 of the light-diffusing particles (A) contained in the composition for a light guide plate was 685 nm.

The cumulative 50% particle diameter D50 (average particle diameter D) of calcium carbonate used as the light-diffusing particle (A) was measured by dynamic light scattering method using a Malvern Zetasizer Nano S manufactured by Parent Company Respectively. Specifically, 1 g of a composition for a light guide plate and 100 g of cyclohexanone were mixed to prepare a dispersion for measurement. The dispersion was sonicated for 10 minutes using an ultrasonic cleaner or a homogenizer. Then, the dispersion was put into a sample inlet of a Zetasizer Nano S, and the particle diameter and the volume of the light-diffusing particle (A) were measured. D50 is the particle diameter at the time when the integrated volume is 50% of the total volume of all the particles when the particle diameter and the volume of the whole particles are measured and the volume is sequentially added starting from the particles having a small particle diameter.

A light guiding substrate made of glass (product name: &quot; OA-10G &quot;, manufactured by Nippon Denshikarasu Co., Ltd., a glass substrate having a surface roughness Ra of 0.5 nm manufactured by an overflow method) was placed on a work stage, Was screen-printed in a dot shape, and then cured by ultraviolet irradiation to prepare a light guide plate. The application conditions and irradiation conditions of ultraviolet rays are as follows.

<Coating Conditions>

The dots were screen-printed under the following conditions. The dot diameter was 300 mu m, the dot film thickness was 15 mu m, and the dot pattern had a pitch gradient design of 500 to 2000 mu m in pitch.

Dimensions of the light guiding board: length (length in the light guiding direction) 718 mm, width 413 mm, thickness 0.7 mm

Coated surface: Outgoing surface (surface of light guiding substrate)

· Application method: Screen printing

· Mesh: 420 mesh / inch

· Squeegee angle: 50 °

· Squeegee speed: 65 mm / s

· Squeegee pressure: 0.198 kgf / cm 2

Clearance: 1.1 mm

<Ultraviolet irradiation condition>

· Lamp: High-pressure mercury lamp (using a short-wavelength cut filter less than 280 nm)

Irradiation dose: 550 mJ / cm 2 (365 nm)

&Lt; Evaluation of luminance unevenness &

A white light diffusion plate was laminated on the non-planar surface of the light guide plate, and a light diffusion film was laminated on the coated surface to produce a side light type backlight. When the sidelight type backlight is observed by visual observation at a position 2 m away from the front side and uniform brightness is detected on the entire surface and luminance unevenness can not be recognized and can be judged to be very good, "⊚" &Quot; is judged to be usable for applications in which strictly uniform luminance is not required, and &quot; Good &quot; is judged to be defective when brightness unevenness is clearly recognized and is difficult to use.

&Lt; Evaluation of degree of yellow color &

Further, when the sidelight type backlight is observed by naked eyes at a position 2 m away from the front and the color is white and can be judged to be very good, &quot;? &Quot;, when it can be judged that the color tone is mixed with a little yellow but is good Quot ;, and &quot; DELTA &quot; when it can be judged that it can be used for applications in which the color tone is slightly yellow but does not require strict white light emission, Respectively.

3.3. Examples 2 to 5 and Comparative Examples 1 to 2

The light-diffusing particles (A) were changed to the particles shown in Table 1, the phosphoric acid ester (B) and the photopolymerizable component (C) were changed to the component amounts shown in Table 1 and the surface roughness Ra of the light- A composition for a light guide plate was prepared and evaluated in the same manner as in Example 1. [ In Table 1, the surface roughness Ra of the light-guiding substrate was adjusted by grinding the alkali-free glass substrate using ceria abrasives to provide the light guide plate.

3.4. Example 6

3.1.1. 5 parts by mass of the hollow particles prepared in the section of "Production of hollow particles" were dispersed in 35.2 parts by mass of bisphenol A epoxy diacrylate (trade name "CN104", manufactured by Arc Machinery Co., Ltd.) using an ultrasonic dispersing machine, (2- (meth) acryloyloxyethyl) -3-phenoxypropyl acrylate (trade name: New Frontier PGA, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as the phosphoric acid ester 0.5 part by mass of a phosphate (Nippon Kayaku Co., Ltd., product name "KAYAMER PM-2") and 0.05 part by mass of hydroquinone monomethyl ether were further mixed, and 1-hydroxycyclohexyl phenyl ketone (manufactured by BASF Japan Co., , Irgacure 184) were mixed to prepare a composition for a light guide plate containing hollow particles as the light-diffusing particles (A).

Using the prepared composition for a light guide plate, coating was carried out in the same manner as in Example 1 and further drying at 100 캜 was carried out to obtain a light guide plate having a light diffusion portion containing hollow particles. The obtained light guide plate was evaluated in the same manner as in Example 1. The results are shown in Table 1.

3.5. Example 7

"3.1.2. 10 parts by mass of the core shell particles prepared in the item &quot; Production of core shell particles &quot;, 35 parts by mass of bisphenol A epoxy diacrylate (trade name: CN104, manufactured by Arc Machinery Co., Ltd.) (2- (meth) acryloyloxy (meth) acrylate as the phosphoric acid ester (B), 42.5 parts by mass of the hydroxy-3-phenoxypropyl acrylate (trade name: New Frontier PGA, manufactured by Daiichi Kogyo Seiyaku Co., 1 part by mass of ethyl acrylate (manufactured by Nippon Kayaku Co., Ltd. under the trade name of "KAYAMER PM-2") and 0.05 part by mass of hydroquinone monomethyl ether were further mixed and then 1-hydroxycyclohexyl phenyl ketone (BASF Japan Co., Ltd., Irgacure 184) were mixed to prepare a composition for a light guide plate containing core shell particles as the light-diffusing particles (A).

A light guide plate was prepared in the same manner as in Example 1 except that a composition for a light guide plate produced by irradiating ultraviolet rays at 500 mJ / cm 2 with a high pressure mercury lamp was used as ultraviolet light irradiation conditions. The obtained light guide plate was evaluated in the same manner as in Example 1. The results are shown in Table 1.

3.6. Example 8

30 parts by mass of the releasing particles prepared in the section &quot; 3.1.3. Preparation of the releasing particles &quot;, 33.6 parts by mass of bisphenol A epoxy diacrylate (trade name: CN104, manufactured by Arc Machinery Co., Ltd.) , 40.9 parts by mass of 2-hydroxy-3-phenoxypropyl acrylate (trade name: New Frontier PGA, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) , 4 parts by mass of 2,2'-azobisisobutyronitrile (manufactured by Nippon Kayaku Co., Ltd. under the trade name of "KAYAMER PM-2") and 0.05 part by mass of hydroquinone monomethyl ether were further mixed, and 1-hydroxycyclohexyl phenyl ketone (BASF (Irgacure 184, manufactured by Nippon Paint Co., Ltd.) were mixed to prepare a composition for a light guide plate containing a release particle as the light-diffusing particles (A).

Using the thus-prepared composition for a light guide plate, coating was carried out in the same manner as in Example 1, and further drying was conducted at 60 캜 for 3 hours to obtain a light guide plate provided with a light diffusing portion containing the releasing particles. The obtained light guide plate was evaluated in the same manner as in Example 1. The results are shown in Table 1.

3.7. Comparative Examples 3 to 5

The phosphoric ester (B) and the photopolymerizable component (C) were changed to the component amounts shown in Table 1, and the surface roughness Ra of the light-guiding substrate to be used was changed to Table 1 , A composition for a light guide plate was prepared and evaluated in the same manner as in Example 7 for Comparative Example 4 and for Example 8 for Comparative Example 5, respectively. In Table 1, the surface roughness Ra of the light-guiding substrate was adjusted by grinding the alkali-free glass substrate using ceria abrasives to provide the light guide plate.

3.8. Example 9

9.5 parts by mass of calcium carbonate particle A (Brilliant 1500 manufactured by Shiraishi Calcium Co., Ltd.), 15.2 parts by mass of an aliphatic polyurethane acrylate (CN985B88, manufactured by Satomaru Japan Co., Ltd.) as a photopolymerizable oligomer 9.5 parts by mass of isobornyl acrylate (Light Acrylate IBXA, manufactured by Kyoeisha Chemical Co., Ltd.) as a photopolymerizable monomer, 1 part by mass of 1,4-butanediol diacrylate (SR213 ), 4.7 parts by mass of hydroxyhexylphenylethylketone (Irgacure 184, manufactured by BASF Japan Co., Ltd.) as a photopolymerization initiator, phenylbis (2,4,6-trimethylbenzoyl) phosphine oxide 2.8 parts by mass of 4,4 '- [1,10-dioxo-1,10-decanediyl] bis (oxy) bis [2,2,6 , 0.04 part by mass of 6-tetramethyl] -1-piperidinyloxy (Irgas Tab UV10, manufactured by BASF Japan K.K.), 10 parts by mass of a dispersant (Nippon Rubrizol Co., (Meth) acryloyloxyethyl) acid phosphate 0.5 part by mass as a phosphate ester (B), 0.5 part by mass of an anthraquinone (Wako Pure Chemical Industries Co., Ltd. by dispersing the light-diffusing particles to processing a mixture comprising ⁴ parts by weight) by the bead mill dispersion machine (a), ^-), Ltd.) to 0.5 × 10 ^{- 4} parts by weight (5.26 × 10 based on 100 parts by mass of the light diffusing particles A composition for a light guide plate containing calcium carbonate particles as the light-diffusing particles (A) was prepared. A light guide plate was prepared and evaluated in the same manner as in Example 1 except that the composition for a light guide plate thus produced was used.

3.9. Examples 10 to 13 and Comparative Example 6

(B), the photopolymerizable component (C) and the colorant (D) were changed to the amounts shown in Table 2, and the amounts of the light-diffusing particles (A) A light guide plate composition was prepared and evaluated in the same manner as in Example 1, except that the surface roughness Ra of the light guide substrate used in Table 2 was used. In Table 2, the surface roughness Ra of the light-guiding substrate was adjusted by grinding the alkali-free glass substrate using ceria abrasives to provide the light guide plate.

3.10. Example 14

3.1.1. 5 parts by mass of the hollow particles prepared in the section of "Production of hollow particles" were dispersed in 35.2 parts by mass of bisphenol A epoxy diacrylate (trade name "CN104", manufactured by Arc Machinery Co., Ltd.) using an ultrasonic dispersing machine, (2- (meth) acryloyloxyethyl) -3-phenoxypropyl acrylate (trade name: New Frontier PGA, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as the phosphoric acid ester 0.5 part by mass of phosphate (manufactured by Nippon Kayaku Co., Ltd. under the trade name of "KAYAMER PM-2") and 0.05 part by mass of hydroquinone monomethyl ether were further mixed and 1-hydroxycyclohexyl phenyl ketone (produced by BASF Japan Co., , Irgacure 184), 0.03 占 10 ^-4 parts by mass of an anthraquinone-based bluing agent (product name: Plast Blue 8514, manufactured by Arimoto Kagaku Kogyo Co., Ltd.) as a colorant (D) relative to 100 parts by weight of particles 0.6 × 10 ^{- 4} parts by weight ) Were mixed to prepare a composition for a light guide plate containing hollow particles as the light-diffusing particles (A).

Using the thus prepared composition for a light guide plate, coating was carried out in the same manner as in Example 1 and further drying at 100 캜 was carried out to obtain a light guide plate having a light diffusion portion containing hollow particles. The obtained light guide plate was evaluated in the same manner as in Example 1. The results are shown in Table 2.

3.11. Example 15

"3.1.2. 10 parts by mass of the core shell particles prepared in the item &quot; Production of core shell particles &quot;, 35 parts by mass of bisphenol A epoxy diacrylate (trade name: CN104, manufactured by Arc Machinery Co., Ltd.) (2- (meth) acryloyloxy (meth) acrylate as the phosphoric acid ester (B), 42.5 parts by mass of the hydroxy-3-phenoxypropyl acrylate (trade name: New Frontier PGA, manufactured by Daiichi Kogyo Seiyaku Co., 1 part by mass of ethyl acrylate (manufactured by Nippon Kayaku Co., Ltd. under the trade name of "KAYAMER PM-2") and 0.05 part by mass of hydroquinone monomethyl ether were further mixed and then 1-hydroxycyclohexyl phenyl ketone (BASF Japan Co., 7.85 parts by mass of Irgacure 184 manufactured by Mitsui Chemicals, Inc.) and 0.09 x 10 ^-4 parts by mass of an anthraquinone-based bluing agent (Plast Blue 8510, product of Arimoto Kagaku Kogyo Co., Ltd.) as a colorant (D) (0.9 x 10 ^{&lt; -4} &gt; parts by mass relative to 100 parts by mass of the light- ) Were mixed to prepare a composition for a light guide plate containing core shell particles as the light-diffusing particles (A).

A light guide plate was prepared in the same manner as in Example 1 except that a composition for a light guide plate manufactured by irradiating ultraviolet light at 500 mJ / cm 2 with a high pressure mercury lamp as an ultraviolet light irradiation condition was used. The obtained light guide plate was evaluated in the same manner as in Example 1. The results are shown in Table 2.

3.12. Example 16

"3.1.3. 30 parts of the modified particles prepared in the section &quot; Production of Dispersion Particles &quot; and 33.6 parts of bisphenol A epoxy diacrylate (trade name: CN104, manufactured by Arc Machinery Co., Ltd.) were dispersed using an ultrasonic dispersing machine, (2- (meth) acryloyloxyethyl) -3-phenoxypropyl acrylate (trade name: New Frontier PGA, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as the phosphoric acid ester 4 parts by weight of a phosphate (Nippon Kayaku Co., Ltd., product name: "KAYAMER PM-2") and 0.05 parts by weight of hydroquinone monomethyl ether were further mixed, and 1-hydroxycyclohexyl phenyl ketone (manufactured by BASF Japan Co., Irgacure 184) 7.85 parts by weight, 8520) to 0.1 × 10 (anthraquinone-based bluing agent (Arimoto Kagaku Kogyo, product name "plast-blue (plast blue as D)) a colorant ⁴ parts by mass of the (light-diffusing 0.33 x 10 &lt;&quot;&gt; ^{- 4} parts by mass based on 100 parts by mass of the particles) To prepare a composition for a light guide plate containing the releasing particles as the light-diffusing particles (A).

Using the thus-prepared composition for a light guide plate, coating was carried out in the same manner as in Example 1, and further drying was conducted at 60 캜 for 3 hours to obtain a light guide plate provided with a light diffusing portion containing the releasing particles. The obtained light guide plate was evaluated in the same manner as in Example 1. The results are shown in Table 2.

3.13. Comparative Examples 7 to 8

The phosphoric ester (B), the photopolymerizable component (C) and the colorant (D) were changed to the component amounts shown in Table 2 while changing the kind of the phosphoric acid ester (B) to butoxyethyl acid phosphate. A composition for a light guide plate was prepared and evaluated in the same manner as in Example 15 for Comparative Example 7 and for the Comparative Example 8, in the same manner as in Example 16, except that the illuminance Ra was as shown in Table 2. In Table 2, the surface roughness Ra of the light-guiding substrate was adjusted by grinding the alkali-free glass substrate using ceria abrasives to provide the light guide plate.

3.14. Evaluation results

Table 1 to Table 2 together show the main composition of the composition for a light guide plate used in Examples 1 to 16 and Comparative Examples 1 to 8 and evaluation results thereof.

The abbreviations in Tables 1 to 2 mean the following components, respectively.

&Lt; Light diffusion particle (A) >

Calcium carbonate particle A: Brilliant 1500 manufactured by Shiraishi Calcium Co., Ltd., D50 = 685 nm

Calcium carbonate particles B: a product of Shiraishi Calcium Co., Ltd., &quot; Silver W &quot;, D50 = 350 nm

Barium sulfate particles: manufactured by Sakai Kagaku Kogyo Co., Ltd., product name: precipitated barium sulfate 100, D50 = 324 nm

Titanium dioxide particle A: product name "Titanium oxide tape R-820N" manufactured by Ishihara Sangyo Co., Ltd., D50 = 433 nm

Titanium dioxide particles B: Titanium oxide JR-1000 manufactured by Teika Corporation, D50 = 643 nm

Hollow particles: 3.1.1. Manufacture of hollow particles ".

Core shell particles: 3.1.2. Manufacture of Core Shell Particles ".

· Discrete particles: those produced in the section 3.1.3, "Production of Discrete Particles".

<Phosphoric ester (B)>

B1: Bis (2- (meth) acryloyloxyethyl) acid phosphate

B2: Butoxyethyl acid phosphate

&Lt; Colorant (D) >

D1: Anthraquinone

D2: Anthraquinone-based bluing agent (product name: Plast Blue 8514, manufactured by Arimoto Kagaku Kogyo Co., Ltd.)

D3: Anthraquinone blue aging agent (Plast Blue 8510, product of Arimoto Kagaku Kogyo Co., Ltd.)

D4: Anthraquinone-based bluing agent (product name: Plast Blue 8520, manufactured by Arimoto Kagaku Kogyo Co., Ltd.)

According to Examples 1 to 16, it can be seen that the light guide plate according to the present invention exhibits good light emission characteristics.

The present invention is not limited to the above embodiment, and various modifications are possible. The present invention includes substantially the same configuration as the configuration described in the embodiment (for example, a configuration in which functions, methods, and results are the same or a configuration in which the purpose and the effect are the same). Further, the present invention includes a configuration in which a non-essential portion of the configuration described in the above embodiments is replaced with another configuration. The present invention also includes configurations that exhibit the same operational effects as those described in the above embodiments, or configurations that can achieve the same purpose. The present invention also includes a configuration in which known technology is added to the configuration described in the above embodiment.

1: light guide plate
3: Light source
11:
12:
20: surface light source device
30: transmission type image display unit
100: transmission type image display device (liquid crystal display device)
S1 · S2: exit surface
S3 ₁ , S3 ₂ , S3 _3, and S3 ₄ :

Claims (10)

The light-diffusing particles (A)
Phosphoric acid ester (B)
Wherein the phosphoric acid ester (B) has a polymerizable functional group. The composition according to claim 1, further comprising a photopolymerizable component (C)
(Mb + Mc) = 0.001 to 0.06 when the content of the phosphoric acid ester (B) is Mb (mass part) and the content of the photopolymerizable component (C) is Mc Composition. The composition for a light guide plate according to claim 1 or 2, wherein the phosphoric acid ester (B) is a compound represented by the following general formula (1).

(In the general formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a divalent organic group, and n represents an integer of 1 or 2) The composition for a light guide plate according to any one of claims 1 to 3, further comprising a hydroquinone derivative. The composition for a light guide plate according to any one of claims 1 to 4, further comprising a colorant (D). The method of claim 5, wherein the light diffusing particles (A) the coloring agent (D) based on 100 parts by mass of 0.01 × 10 ^-4 to 10 × 10 ^-4 parts by weight containing composition for light guide plate. The composition for a light guide plate according to claim 5 or 6, wherein the coloring agent (D) is a blueing agent. A light guide plate comprising a light-guiding substrate and a light diffusion portion,
Wherein the value of the surface roughness Ra of the light-guiding substrate is Ra < 1 nm,
Wherein the light diffusing portion contains light diffusing particles (A) having an average particle diameter D (nm)
200 < D / Ra < 5000. A method for manufacturing a light guide plate including a light guiding plate and a light diffusion portion,
On the light guide substrate having a surface roughness Ra of Ra < 1 nm,
A light diffusing plate composition according to any one of claims 1 to 7, wherein the light diffusing particle (A) having an average particle diameter D (nm) is contained and 200 < D / Ra < Wherein the light guide plate is made of a metal. An edge light type surface emitting device comprising the light guide plate according to claim 8.

Images