CN100489618C - Brightness strengthening film for LCD and its manufacturing method - Google Patents

Abstract

A liquid crystal display having a brightness enhancement film and a method of manufacturing the brightness enhancement film, the method including providing a solution of high molecular weight resin on a high molecular weight film, uniformly distributing the solution of high molecular weight resin on the high molecular weight film, and drying the solution of high molecular weight resin to form a high molecular weight resin layer, wherein the high molecular weight resin layer has a hexagonal lattice structure.

Description

Brightness enhancement film for liquid crystal display and manufacturing method thereof

technical field

The invention relates to a brightness enhancement film for liquid crystal displays and a manufacturing method thereof.

Background technique

Liquid crystal display (LCD) is one of the most widely used flat-panel display devices at present. It is composed of two substrates formed with electrodes that generate an electric field and a liquid crystal layer interposed between them, and a voltage is applied to the electrodes to rearrange the liquid crystal. layer of liquid crystal molecules, thereby adjusting the light transmittance of the liquid crystal layer of the display device.

Such a liquid crystal display includes: a backlight section that generates light; an optical sheet section that makes the brightness of light from the backlight section uniform; and a display section that displays images using the uniform light.

Among them, the optical sheet part is composed of diffusion film, prism film and brightness enhancement film. The brightness enhancement film is formed by laminating more than hundreds of thin films, so it has a thickness of 140 to 440 μm, and the manufacturing process is complicated.

Also, the diffusion film, the prism film, and the brightness enhancement film of the optical sheet portion are formed independently and arranged at predetermined intervals, respectively.

However, with the enlargement of liquid crystal displays, diffusion films, prism films, and brightness enhancement films made of different materials expand to different extents due to temperature and humidity, and this inconsistent expansion tends to cause ripples. Furthermore, such a moire shape of the optical sheet portion causes display defects such as spots.

Contents of the invention

According to an embodiment of the present invention, there is provided a method of manufacturing a brightness enhancement film for a liquid crystal display, the method comprising the steps of: providing a polymer resin solution on the polymer film; on the molecular film; and drying the polymer resin solution to form a polymer resin layer, wherein the polymer resin layer has a hexagonal lattice structure.

According to an embodiment of the present invention, it further includes a step of thermally stretching the polymer film and the polymer resin layer in a predetermined direction.

Preferably, the polymer film may comprise polycarbonate or polyethylene terephthalate material.

The thickness of the hexagonal lattice structure of the polymer resin layer is about 10nm to 800nm.

The polymer resin solution is uniformly coated on the polymer film by using a spin coating method or a blade mounting method.

Preferably, the polymer resin layer comprises polysulfone, polymethyl methacrylate, polystyrene, polyvinyl chloride, polyvinyl alcohol, polynorbornene, a polymer formed by copolymerization of the above-identified polymers, or One of the derivatives.

The thermal extension treatment temperature of the polymer film is between the glass transition temperature of the polymer film and the glass transition temperature+100°C.

The length of the polymer film and the polymer resin layer after thermal stretching is 1.1 to 8 times longer than that before thermal stretching.

According to an embodiment of the present invention, there is provided a brightness enhancement film for a liquid crystal display, comprising: a polymer film; and a polymer resin layer formed on the polymer film, wherein the polymer resin layer has a hexagonal lattice structure.

Preferably, the polymer film and the polymer resin layer are thermally stretched in a predetermined direction.

The polymer film is polycarbonate or polyethylene terephthalate material.

The thickness of the hexagonal lattice structure of the polymer resin layer is about 10nm to 800nm.

The polymer resin layer contains polysulfone, polymethyl methacrylate, polystyrene, polyvinyl chloride, polyvinyl alcohol, polynorbornene, a polymer formed by copolymerization of the above-identified polymers, or a derivative thereof kind of.

According to an embodiment of the present invention, a method for manufacturing a liquid crystal display is provided, comprising the steps of: disposing a first ultraviolet crosslinking agent on a diffusion film; uniformly coating the first ultraviolet crosslinking agent on the diffusion film; The enhanced film is placed on the first ultraviolet cross-linking agent; the second ultraviolet cross-linking agent is arranged on the brightness enhancement film; the second ultraviolet cross-linking agent is evenly coated on the brightness enhancement film; the prism film is placed on the second ultraviolet cross-linking agent on the agent; irradiating ultraviolet rays to the first and second ultraviolet crosslinking agents, wherein a polymer resin layer with a hexagonal lattice structure is formed on the polymer film of the brightness enhancement film.

Preferably, the first and second ultraviolet crosslinking agents are uniformly coated on the diffusion film and the brightness enhancement film respectively by using a spin coating method or a blade mounting method.

According to an embodiment of the present invention, there is provided a liquid crystal display, comprising: a display portion capable of displaying images; a backlight portion supplying light to the display portion; and an optical sheet portion located between the display portion and the backlight portion, and comprising There are a diffusion film, a prism film, and a brightness enhancement film, wherein the brightness enhancement film includes a polymer film and a polymer resin layer formed on the polymer film and having a hexagonal lattice structure.

A brightness enhancement film is formed on the diffusion film, and a prism film is formed on the brightness enhancement film.

The liquid crystal display above further includes: attaching the diffusion film and the brightness enhancement film with a first ultraviolet crosslinking agent; and attaching the brightness enhancement film and the prism film with a second ultraviolet crosslinking agent.

According to an embodiment of the present invention, there is provided a method of manufacturing a brightness enhancement film for a liquid crystal display, the method comprising the following steps: laminating a plurality of photocrystalline colloidal particles in a photocrystalline colloid on a polymer film; and Predetermined stacking a plurality of optical crystallization colloids to form a photocrystallization colloid layer; wherein the stacked plurality of optical crystallization colloids is composed of a predetermined lattice structure.

A plurality of laminated optical crystal colloids are composed of 111 or 100 lattice structures.

The above-mentioned method for manufacturing a brightness enhancement film for a liquid crystal display further includes the steps of: adding and stirring deionized water, an emulsifier, and a neutralizing agent to the inside of the reactor; adding styrene monomer to the inside of the reactor; Initiator is injected internally.

The process of laminating a plurality of optical crystal colloids in the optical crystal colloid on the polymer film includes the following steps: soaking the substrate attached to the polymer film in a container containing the optical crystal colloid; The substrate is taken out from the photocrystal colloid and dried, so that a plurality of photocrystal colloids are laminated on the polymer film.

The above-mentioned method for manufacturing a brightness enhancement film for a liquid crystal display further includes a step of sequentially stacking another polymer film and a photocrystal colloid layer on the photocrystal colloid layer to form a plurality of brightness enhancement films.

The size of photocrystal colloidal particles ranges from a few nanometers to hundreds of nanometers.

The polymer resin layer contains polycarbonate, polyethylene terephthalate, polyimide, polyamide, polyether, polysulfone, polypropylene, polymethyl methacrylate, polypropylene, cellulose acetate, One of the polymers formed by the copolymerization of the above-identified polymers, or derivatives thereof.

According to an embodiment of the present invention, a brightness enhancement film for a liquid crystal display is provided, comprising: a polymer film; Colloidal particles consist of a predetermined lattice structure.

A plurality of optical crystal colloids are composed of 111 or 100 lattice structures.

The polymer resin layer contains polycarbonate, polyethylene terephthalate, polyimide, polyamide, polyether, polysulfone, polypropylene, polymethyl methacrylate, polypropylene, cellulose acetate, One of the polymers formed by the copolymerization of the above-identified polymers, or derivatives thereof.

Preferably, the size of the optical crystal colloidal particles is several nanometers to hundreds of nanometers.

According to an embodiment of the present invention, a method for manufacturing a liquid crystal display is provided, comprising the steps of: disposing a first ultraviolet crosslinking agent on a diffusion film; uniformly coating the first ultraviolet crosslinking agent on the diffusion film; The enhancement film is placed on the first ultraviolet cross-linking agent; the brightness enhancement film is provided with the second ultraviolet cross-linking agent; the brightness enhancement film is evenly coated with the second ultraviolet cross-linking agent; the prism film is placed on the second ultraviolet cross-linking agent ; irradiating ultraviolet rays to the first and second ultraviolet crosslinking agents, wherein the brightness enhancement film is composed of photocrystal colloids formed on the polymer film, and a plurality of photocrystal colloids of the photocrystal colloid layer have a predetermined lattice structure composition.

Preferably, the first and second ultraviolet crosslinking agents are uniformly coated on the diffusion film and the brightness enhancement film respectively by using a spin coating method or a blade mounting method.

According to an embodiment of the present invention, there is provided a liquid crystal display, comprising: a display portion capable of displaying images; a backlight portion supplying light to the display portion; and an optical sheet portion located between the display portion and the backlight portion, and comprising There are diffusion films, prism films, and brightness enhancement films, wherein the brightness enhancement film includes a polymer film, a photocrystal colloid layer formed on the polymer film, and a plurality of photocrystal colloid ions in the photocrystal colloid layer have predetermined lattice structure.

Preferably, a brightness enhancement film is formed on the diffusion film, and a prism film is formed on the brightness enhancement film.

Preferably, the brightness enhancement film has a thickness of several micrometers to several millimeters.

According to an embodiment of the present invention, a method for manufacturing a brightness enhancement film for a liquid crystal display is provided, comprising the steps of: setting a polymer solution containing metal ions on a substrate; uniformly coating the polymer solution containing metal ions on the substrate; and drying the polymer solution containing the metal ions to form a polymer film in which the metal ions are distributed in a predetermined lattice structure.

The polymer solution containing metal ions is a mixed solution of a substance containing AgCl or CuCl ₂ metal ions and a polymer resin with acid radicals.

Preferably, the polymer resin layer comprises polycarbonate, polyethylene terephthalate, polyimide, polysulfone, polymethyl methacrylate, polypropylene, polyvinyl chloride, polyvinyl alcohol, polyoxyl One of bornene, a polymer formed by copolymerization of the above-identified polymers, or a derivative thereof.

The above-mentioned method for manufacturing a brightness enhancement film for a liquid crystal display further includes a step of thermally stretching the polymer film in a predetermined direction.

Preferably, the heat stretching treatment temperature of the polymer film is between the glass transition temperature of the polymer film and the glass transition temperature+100 degrees.

Preferably, the thermally stretched polymer film has a length greater than 1.1 to 8 times the length before thermal stretching.

According to an embodiment of the present invention, there is provided a method for manufacturing a brightness enhancement film for a liquid crystal display, comprising the following steps: melting a polymer resin and metal particles; cooling the melted polymer resin and metal particles with a cooling roller, and forming Polymer film, in which metal ions are distributed in the polymer film while forming a predetermined lattice structure.

Preferably, the polymer resin layer comprises polycarbonate, polyethylene terephthalate, polyimide, polysulfone, polymethyl methacrylate, polypropylene, polyvinyl chloride, polyvinyl alcohol, polyoxyl One of bornene, a polymer formed by copolymerization of the above-identified polymers, or a derivative thereof.

Preferably, the metal ions are gold or silver ions with a size of a few nm, and have a face-centered cubic lattice structure, and are distributed in the polymer film.

The melted polymer resin and metal particles are in powder form.

The melting temperature of the powdery polymer resin and powdery metal ions is between the glass transition temperature and the glass transition temperature+180°C.

The temperature of the cooling drum is 100 to 140°C.

Preferably, the concentration of the polymer resin is between about 70wt% and 99.9wt%, and the concentration of the metal particles is between about 0.1wt% and 30wt%.

The above-mentioned method for manufacturing a brightness enhancement film for a liquid crystal display further includes a step of thermally stretching the polymer film in a predetermined direction.

Preferably, the heat stretching treatment temperature of the polymer film is from the glass transition temperature of the polymer film to the glass transition temperature + 100°C.

The length of the thermally stretched polymer film is 1.1 to 8 times the length before thermal stretching.

According to an embodiment of the present invention, there is provided a brightness enhancement film for a liquid crystal display, comprising a polymer film structure including a predetermined lattice formed by a plurality of metal particles or a plurality of metal ion particles.

Preferably, the polymer film is thermally stretched in a predetermined direction.

Preferably, the polymer resin layer comprises polycarbonate, polyethylene terephthalate, polyimide, polysulfone, polymethyl methacrylate, polypropylene, polyvinyl chloride, polyvinyl alcohol, polyoxyl One of bornene, a polymer formed by copolymerization of the above-identified polymers, or a derivative thereof.

Preferably, the metal particles and/or metal ion particles are gold, silver, or copper.

According to an embodiment of the present invention, a method for manufacturing a liquid crystal display is provided, comprising the steps of: disposing a first ultraviolet crosslinking agent on a diffusion film; uniformly coating the first ultraviolet crosslinking agent on the diffusion film; The enhancement film is placed on the first ultraviolet cross-linking agent; the brightness enhancement film is provided with the second ultraviolet cross-linking agent; the brightness enhancement film is evenly coated with the second ultraviolet cross-linking agent; the prism film is placed on the second ultraviolet cross-linking agent and irradiating ultraviolet rays to the first and second ultraviolet crosslinking agents, wherein a plurality of metal particles or metal ion particles forming a predetermined lattice structure are distributed in the polymer film of the brightness enhancement film.

Preferably, the first and second ultraviolet crosslinking agents are uniformly coated on the diffusion film and the brightness enhancement film respectively by using a spin coating method or a blade mounting method.

According to an embodiment of the present invention, a liquid crystal display is provided, including: a display part capable of displaying images; a backlight part providing light to the display part; an optical sheet part located between the display part and the backlight part, and including Diffusion film, prism film and brightness enhancement film, wherein the brightness enhancement film with polymer film structure includes a predetermined lattice formed by a plurality of metal particles or metal ion particles.

Preferably, the brightness enhancement film is formed on the diffusion film, and the prism film is formed on the brightness enhancement film.

Preferably, the diffusion film and the brightness enhancement film are attached with the first ultraviolet crosslinking agent, and the brightness enhancement film and the prism film are attached with the second ultraviolet crosslinking agent.

According to an embodiment of the present invention, there is provided a method for manufacturing a brightness enhancement film for a liquid crystal display, comprising the steps of: coating a liquid crystal composed of a plurality of encapsulated liquid crystal molecules on a polymer film; A plurality of encapsulated liquid crystal molecules are aligned to form a liquid crystal layer, wherein the encapsulated liquid crystal molecules are in a tiny crystal structure.

Preferably, the encapsulated liquid crystal molecules have a size of more than tens of nanometers and less than hundreds of nanometers.

Preferably, the method for manufacturing a liquid crystal composed of encapsulated liquid crystal molecules comprises the following steps: putting and stirring deionized water and an emulsifier into the reactor; putting styrene monomer and nematic or smectic liquid crystal into the reactor ; Put the initiator into the reactor.

Preferably, the liquid crystal composed of encapsulated liquid crystal molecules is in a colloidal state.

Preferably, the plurality of encapsulated liquid crystal molecules are aligned in parallel in a predetermined direction due to friction or application of an electric field.

Preferably, the polymer resin layer comprises polycarbonate, polyethylene terephthalate, polyimide, polysulfone, polymethyl methacrylate, polypropylene, polyvinyl chloride, polyvinyl alcohol, polyoxyl One of bornene, a polymer formed by copolymerization of the above-identified polymers, or a derivative thereof.

The above-mentioned method for manufacturing a brightness enhancement film for a liquid crystal display further includes a step of thermally stretching the polymer film and the liquid crystal layer in a predetermined direction.

Preferably, the heat stretching treatment temperature of the polymer film is between the glass transition temperature of the polymer film and the glass transition temperature+100°C.

Preferably, the thermally stretched polymer film and the liquid crystal layer have a length greater than 1.1 to 8 times the length before thermal stretching.

According to an embodiment of the present invention, a brightness enhancement film for a liquid crystal display is provided, comprising: a polymer film; and a liquid crystal layer formed on the polymer film, wherein a plurality of encapsulated liquid crystal molecules of the liquid crystal layer are tiny Crystalline structure, and oriented in a certain direction.

Preferably, the polymer film and the encapsulated liquid crystal layer are thermally extended in a predetermined direction.

Preferably, the polymer resin layer comprises polycarbonate, polyethylene terephthalate, polyimide, polysulfone, polymethyl methacrylate, polypropylene, polyvinyl chloride, polyvinyl alcohol, polyoxyl One of bornene, a polymer formed by copolymerization of the above-identified polymers, or a derivative thereof.

Preferably, the liquid crystal molecules have a size of more than tens of nanometers and less than hundreds of nanometers

According to an embodiment of the present invention, a method for manufacturing a liquid crystal display is provided, comprising the steps of: disposing a first ultraviolet crosslinking agent on a diffusion film; uniformly coating the first ultraviolet crosslinking agent on the diffusion film; The enhancement film is placed on the first ultraviolet cross-linking agent; the brightness enhancement film is provided with the second ultraviolet cross-linking agent; the brightness enhancement film is evenly coated with the second ultraviolet cross-linking agent; the prism film is placed on the second ultraviolet cross-linking agent and irradiating ultraviolet rays to the first and second ultraviolet crosslinking agents, wherein a liquid crystal layer in which a plurality of encapsulated liquid crystal molecules are aligned in a predetermined direction is formed on the polymer film of the brightness enhancement film.

Preferably, the first and second ultraviolet crosslinking agents are uniformly coated on the diffusion film and the brightness enhancement film respectively by using a spin coating method or a blade mounting method.

Preferably, there are more than one brightness enhancement film.

According to an embodiment of the present invention, a liquid crystal display is provided, comprising: a display portion capable of displaying images; a backlight portion supplying light to the display portion; an optical sheet portion located between the display portion and the backlight portion, and including The diffusion film, the prism film and the brightness enhancement film, wherein the brightness enhancement film includes a polymer film, a liquid crystal layer formed on the polymer film and encapsulating a plurality of liquid crystal molecules aligned in parallel in a predetermined direction.

Preferably, the brightness enhancement film is formed on the diffusion film, and the prism film is formed on the brightness enhancement film.

Preferably, the diffusion film and the brightness enhancement film are attached with the first ultraviolet crosslinking agent, and the brightness enhancement film and the prism film are attached with the second ultraviolet crosslinking agent.

According to an embodiment of the present invention, there is provided a method for manufacturing a brightness enhancement film for a liquid crystal display, comprising the steps of: melting organic particles with a polymer resin core-shell structure; cooling the melted polymer resin and organic particles with a cooling roller , to manufacture a polymer film; heat-treating the polymer film in a predetermined direction; and distributing organic particles with a core-shell structure in the polymer film.

Preferably, the core-shell structured organic particles consist of methacrylate-butadiene-styrene.

Preferably, the polymer resin layer comprises polycarbonate, polyethylene terephthalate, polyimide, polysulfone, polymethyl methacrylate, polypropylene, polyvinyl chloride, polyvinyl alcohol, polyoxyl One of bornene, a polymer formed by copolymerization of the above-identified polymers, or a derivative thereof.

Preferably, the polymer resin and the metal particles are in powder form, and the melting temperature of the polymer resin and the metal particles is between the glass transition temperature and the glass transition temperature+180°C.

Preferably, the glass transition temperature is between about 300°C and 330°C.

Preferably, the cooling temperature is between about 100°C and 140°C.

Preferably, the concentration of the polymer resin is between about 70wt% and 99wt%, and the concentration of the organic particles is between about 1wt% and 30wt%.

Preferably, the heat stretching treatment temperature of the polymer film is between the glass transition temperature of the polymer film and the glass transition temperature+100°C.

Preferably, the thermally stretched polymer film has a length greater than 1.1 to 8 times the length before thermal stretching.

According to an embodiment of the present invention, a brightness enhancement film for a liquid crystal display is provided, comprising a polymer film and organic particles, the organic particles have a core-shell structure and are distributed in the polymer film.

Preferably, the polymer film is thermally stretched in a predetermined direction.

Preferably, the polymer resin layer comprises polycarbonate, polyethylene terephthalate, polyimide, polysulfone, polymethyl methacrylate, polypropylene, polyvinyl chloride, polyvinyl alcohol, polyoxyl One of bornene, a polymer formed by copolymerization of the above-identified polymers, or a derivative thereof.

Preferably, the core-shell structured organic particles consist of methacrylate-butadiene-styrene.

According to an embodiment of the present invention, a method for manufacturing a liquid crystal display is provided, comprising the steps of: disposing a first ultraviolet crosslinking agent on a diffusion film; uniformly coating the first ultraviolet crosslinking agent on the diffusion film; The enhancement film is placed on the first ultraviolet cross-linking agent; the brightness enhancement film is provided with the second ultraviolet cross-linking agent; the brightness enhancement film is evenly coated with the second ultraviolet cross-linking agent; the prism film is placed on the second ultraviolet cross-linking agent and irradiating ultraviolet rays to the first and second ultraviolet crosslinking agents, wherein a plurality of organic particles with a core-shell structure are distributed in the polymer film of the brightness enhancement film.

Preferably, the first and second ultraviolet crosslinking agents are uniformly coated on the diffusion film and the brightness enhancement film respectively by using a spin coating method or a blade mounting method.

According to an embodiment of the present invention, there is provided a liquid crystal display, comprising: a display portion capable of displaying images; a backlight portion supplying light to the display portion; and an optical sheet portion located between the display portion and the backlight portion, and comprising There are diffusion film, prism film and brightness enhancement film, among which the brightness enhancement film distributes a plurality of organic particles with core-shell structure in the polymer film.

Preferably, the brightness enhancement film is formed on the diffusion film, and the prism film is formed on the brightness enhancement film.

Preferably, the diffusion film and the brightness enhancement film are attached with the first ultraviolet crosslinking agent, and the brightness enhancement film and the prism film are attached with the second ultraviolet crosslinking agent.

Description of drawings

1 is a cross-sectional view of a liquid crystal display including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

2 to 5 show the sequence of a method for manufacturing a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

6 to 9 illustrate the sequence of a liquid crystal display manufacturing method including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

10 is a cross-sectional view of a liquid crystal display including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

Figure 11A shows a plurality of optical crystal colloids forming a 111 lattice shape and stacked on a polymer film;

Figure 11B shows a plurality of optical crystal colloids forming a 100 lattice shape and stacked on a polymer film;

Figure 12 shows the reactor for producing photocrystalline colloids;

13A to 13D illustrate the sequence of a method of manufacturing a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

Fig. 14 shows the state of forming the first and second photocrystalline stratum corneum;

FIGS. 15A to 16 illustrate the sequence of a liquid crystal display manufacturing method including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

17 is a cross-sectional view of a liquid crystal display including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

18 is a perspective view and a partially enlarged view of a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

FIG. 19 to FIG. 21 and FIG. 23 show the sequence of a method for manufacturing a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

Fig. 22A is the chemical formula of the macromolecular resin with acid radical, and Fig. 22B is the chemical formula of the polyimide formed according to the dehydration reaction when the macromolecular resin is dried;

FIG. 24 illustrates an additional method of manufacturing a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

25A to 26 illustrate the sequence of a liquid crystal display manufacturing method including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

27 is a cross-sectional view of a liquid crystal display including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

Figure 28 shows liquid crystal molecules with a fine crystal structure;

Figure 29 shows a reactor for making encapsulated liquid crystals;

30 to 32 show the sequence of a method for manufacturing a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

33A to 34 illustrate the sequence of a liquid crystal display manufacturing method including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

35 is a cross-sectional view of a liquid crystal display including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

36 is a perspective view of a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention;

Fig. 37 is the organic ion chemical formula of core-shell structure;

38 to 40 illustrate the sequence of a method of manufacturing a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention; and

41A to 42 show a sequence of a method of manufacturing a liquid crystal display including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention.

Symbol Description

4: Substrate 75: Metal ion particles

8: Liquid crystal molecules 9: Encapsulated liquid crystal molecules

10: Optical crystal particles 20: Polymer resin

141: Diffusion film 142: Brightness enhancement film

143: Prism film 144: Polymer film

145, 345: polymer resin 146: the first ultraviolet crosslinking agent

147: The second ultraviolet crosslinking agent 245: Optical crystal colloidal layer

Detailed ways

An object of the present invention is to provide a brightness enhancement film for a liquid crystal display and a method for manufacturing the same, which shortens the manufacturing process and reduces concave portions.

In order to enable those skilled in the art to practice the present invention, embodiments of the present invention will now be described in detail with reference to the accompanying drawings. However, the present invention can be embodied in different forms, and it is not limited to the embodiments described here.

In the drawings, the thicknesses and regions of layers are exaggerated for clarity. Where the same symbols are attached to the same elements throughout the specification, it should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another part, it means that it is directly on the other element, or There may also be other elements intervening. In contrast, when an element is referred to as being "directly" on other parts, it means that there are no intervening elements.

Hereinafter, a brightness enhancement film for a liquid crystal display and a manufacturing method thereof according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view of a liquid crystal display including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention.

As shown in FIG. 1 , a liquid crystal display 100 including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention includes a display part 130 displaying an image, a backlight part 145 located on the display part and providing light to the display part 130, The optical sheet part 140 intervenes in the display part 130 and the backlight part 150 and makes the luminance from the backlight part 150 uniform. Furthermore, the display unit 130 is composed of a thin film transistor display panel 131 , a color filter display panel 132 facing the thin film transistor display panel 131 , and a liquid crystal layer 135 interposed between the display panels 131 , 132 . Also, lower and upper polarizing plates 133, 134 are disposed outside the thin film transistor display panel 131 and the color filter display panel 132, respectively.

The thin film transistor display panel 131 has a plurality of pixel electrodes (not shown) arranged in a row, a plurality of thin film transistors (not shown) selectively transmitting signals to the pixel electrodes, and a plurality of gate lines (not shown) connected to the thin film transistors ( not shown) and multiple data lines (not shown).

The color filter display panel 132 includes a common electrode that generates an electric field together with the pixel electrodes and color filters that display colors. When a voltage is applied to the pixel electrode and the common electrode, an electric field is formed to change the arrangement of liquid crystal molecules located therebetween.

The backlight unit 150 has a plurality of lamps 151 that generate light, and a light guide plate 152 that guides the light from the lamps 151 to the display unit. The lamp 151 shown in FIG. 1 is a direct type in which the lamp 151 is placed under the display portion 151 and the light guide plate 150 . The light guide plate 150 is located under the display part 130 and has a size corresponding to the display part 130 . As shown in FIG. 1 , the light guide plate 150 may have a uniform thickness, or its thickness may gradually increase or decrease.

On the upper part of the light guide plate 150, an optical sheet part 140 is arranged to make the brightness toward the display part 130 uniform, and on the lower part of the backlight part 130, a reflective plate 160 is arranged to re-reflect from the light guide plate 150 to improve light efficiency.

The optical sheet 140 is composed of multiple optical sheets. That is, the optical sheet part 140 is composed of a diffusion film 141 that diffuses the light generated by the backlight part 150 to make the brightness distribution uniform, a brightness enhancement film 142 that transmits the P wave in the light source, and reuses the S wave to increase the brightness, and condenses the light. The prism film 143 consists of uniformly distributed light.

A brightness enhancement film 142 is formed on the diffusion film 141 , and a prism film 143 is formed on the brightness enhancement film 142 .

The diffusion film 141 and the brightness enhancement film 142 are attached by the first ultraviolet crosslinking agent 146, and the brightness enhancement film 142 and the prism film 143 are attached by the second ultraviolet crosslinking agent 147, so that the optical sheet part 140 is integrated.

In this way, the diffusion film 141, the brightness enhancement film, and the prism film 143 are integrally formed to prevent a concave portion between the diffusion film 141, the brightness enhancement film 142, and the prism film 143 that are different from each other when they are expanded due to temperature and humidity.

The brightness enhancement film 142 is composed of a polymer film 144 and a polymer resin layer 145 having a hexagonal structure 45 lattice formed on the polymer film 144 .

Preferably, the polymer film 144 can be made of polycarbonate or polyethylene terephthalate or the like.

Preferably, the polymer resin layer comprises polysulfone, polymethyl methacrylate, polystyrene, polyvinyl chloride, polyvinyl alcohol, polynorbornene, a polymer formed by copolymerization of the above-identified polymers, or One of the derivatives.

Preferably, the hexagonal lattice 45 structure of the polymer resin layer 145 has a size and diameter of about 10 nm to 800 nm.

The polymer resin layer 145 having such a hexagonal lattice structure has reflective polarization properties. That is, lattice P waves passing through the hexagonal lattice 45 are passed, and S waves are reflected to exhibit reflective polarization characteristics.

The light generated in the backlight part 150 includes P waves and S waves, the P waves are passed through the brightness enhancement film 142 having reflective polarization characteristics, the S waves are reflected, and only the P waves are supplied to the display part.

Therefore, for light having a wavelength of 250 to 800 nm, the brightness enhancement film 142 transmits P waves and reflects S waves. And the S wave reflected from the brightness enhancement film 142 is re-reflected by the reflector 160 into a P′ wave and an S′ wave, wherein the P′ wave is transmitted, and the S′ wave is reflected by the brightness enhancement film 142 and rereflected by the reflector 160 . Repeating this process makes the P wave passing through the polymer resin layer 145 larger on both sides to increase brightness.

Moreover, the brightness enhancement film 142 is thermally stretched in a predetermined direction, so as to further improve the reflective polarization characteristic of the brightness enhancement film 142 . That is, the hexagonal lattice 45 is arranged in the extending direction, and a refractive index difference is generated between the extending direction and the non-extending direction, so as to further improve the reflective polarization characteristic.

Preferably, the length of the thermally stretched brightness enhancement film 142 is 1.1 to 8 times longer than that before thermally stretched.

The conventional brightness enhancement film 142 has a thickness of 140 to 440 μm due to the lamination of hundreds of thin films, and the manufacturing process is complicated. However, the brightness enhancement film 142 as an embodiment of the present invention only uses a single layer or multiple layers with emission polarization characteristics, Therefore, the thickness of the brightness enhancement film 142 is thin, which simplifies the manufacturing process.

Next, a method of manufacturing the brightness enhancement film 142 for a liquid crystal display according to the present invention having the structure as described above will be described with reference to FIGS. 2 to 5 .

First, as shown in FIG. 2 , a polymer resin solution is provided on the polymer film 144 . The polymer film is a polycarbonate film or a polyethylene terephthalate (PET) film, and the polymer resin solution 145 is a mixed solution of a polymer resin and water.

Then, as shown in FIG. 3A and FIG. 3B , the polymer resin solution 145 is uniformly coated on the polymer film 144 by a spin coating method or a blade mounting method.

As shown in FIG. 3A , the spin coating method is a method of rotating the polymer film 144 to uniformly coat the polymer resin solution 145 with a certain thickness. As shown in FIG. 3B , the mounted blade method is a method of uniformly coating the polymer solution 145 with a certain thickness using a roller 55 .

Then, as shown in FIG. 4 , the polymer resin solution 145 is dried to form a polymer resin layer 145 . That is, drying is carried out at a temperature of 4° C. to 100° C., preferably, the polymer resin layer 145 formed with the hexagonal lattice 45 is dried on a portable electric furnace at a temperature of 40° C. to 60° C.

Preferably, the polymer film is polycarbonate, polyethylene terephthalate, polyimide, polysulfone, polymethyl methacrylate, polystyrene, polyvinyl chloride, polyvinyl alcohol, polyoxyl One of bornene, a polymer formed by copolymerization of the above-identified polymers, or a derivative thereof.

Next, as shown in FIG. 5 , the brightness enhancement film 143 composed of the polymer film 144 and the polymer resin layer 145 is thermally stretched in a predetermined direction, that is, the X direction.

Preferably, the thermal stretching temperature is between the glass transition temperature of the polymer film 144 and the glass transition temperature + 100°C. Preferably, the length of the thermally stretched brightness enhancement film 142 is 1.1 to 1.1 times longer than that of the non-thermally stretched one. 8 times.

Here, the glass transition temperature of the polymer film 144 refers to the temperature at which the Brownian motion of ions in the polymer film 144 is the most free. When the glass transition temperature of the polymer film 144 is exceeded, the polymer film 144 is in a state where thermal stretching is easy. For example, the glass transition temperature of polyethylene terephthalate (PET) is about 75°C.

In this way, thermal stretching is performed to increase the lattice size of the polymer resin layer 145 in the X direction to better polarize light. That is, the lattice of the hexagonal lattice 45 is arranged in the extending direction, and a refractive index difference is generated between the extending direction and the non-extending one, so as to further improve the reflective polarization characteristic. The P wave is transmitted and the S wave is reflected, so as to improve the reflected polarization characteristics recovered by the reflective plate 160 , thereby increasing the amount of P wave passing through the polymer resin layer 145 and increasing brightness.

Next, a method of manufacturing a liquid crystal display including the brightness enhancement film 142 for a liquid crystal display of the present invention having the structure as described above will be described with reference to FIGS. 6 to 9 .

First, as shown in FIG. 6 , a first ultraviolet crosslinking agent 146 in a solution state is provided on the diffusion film 141 .

Next, as shown in FIGS. 7A and 7B , the first ultraviolet crosslinking agent 146 is evenly coated on the diffusion film 141 .

That is, as shown in FIG. 7A, the diffusion film 141 is rotated by the spin coating method, and the first ultraviolet crosslinking agent 146 is evenly coated with a certain thickness on the diffusion film 141, or as shown in FIG. In the film 141 , the first ultraviolet crosslinking agent 146 is uniformly applied to a certain thickness on the diffusion film 141 by the roller 55 .

Next, as shown in FIGS. 8A and 8B , the brightness enhancement film 142 is disposed on the first ultraviolet crosslinking agent 146 . The brightness enhancement film 142 has a structure in which a polymer resin layer 145 having a hexagonal lattice 45 lattice is formed on a polymer film 144 .

The polymer resin layer 145 having such a hexagonal lattice structure has reflective polarization properties. Therefore, the brightness enhancement film transmits the P-wave cut and reflects the S-wave. Also, the S wave reflected at the brightness enhancement film 142 is re-reflected by the reflection plate 160 into a P' wave and an S' wave, wherein the P' wave is transmitted and S' is reflected at the brightness enhancement film, and then S' is reflected by the re-reflection plate. This process is repeated so that the amount of P wave passing through the polymer resin layer 145 increases brightness.

Also, a second ultraviolet crosslinking agent 147 in a solution state is provided on the brightness enhancement film 142 . Then, the second ultraviolet crosslinking agent 147 is uniformly coated on the diffusion plate 141 .

That is, as shown in FIG. 8A, the diffusion film 141 is rotated by the spin coating method to uniformly coat the second ultraviolet crosslinking agent 147 with a certain thickness on the diffusion film 141, or as shown in FIG. For the diffusion film, the second ultraviolet crosslinking agent 147 is uniformly coated on the diffusion film 141 with a roller to a certain thickness.

Next, as shown in FIG. 9 , a prism film 143 is disposed on the second ultraviolet crosslinking agent 147 . Then, the first and second ultraviolet crosslinking agents 146, 147 are irradiated with ultraviolet rays, the diffusion film 141 and the brightness enhancement film 142 are attached to each other by the first ultraviolet crosslinking agent 146, and the brightness enhancement films are attached to each other by the second ultraviolet crosslinking agent 147. 142 and prism film 143.

In this way, the diffusion film 141 , the brightness enhancement film 142 and the prism film 143 of the liquid crystal display optical sheet portion 140 are integrally formed to prevent recesses between the diffusion film 141 , the brightness enhancement film 142 and the prism film 143 .

As described above, although the first and second ultraviolet crosslinking agents 146, 147 are irradiated with ultraviolet rays simultaneously to attach the diffusion film 141, the brightness enhancement film 142, and the brightness enhancement film 142 and the prism film 143 at the same time, it is also possible to crosslink the first ultraviolet rays. Linking agent 146 irradiates ultraviolet rays—adhesive diffusion film 141 and brightness enhancement film 142, then coats second ultraviolet crosslinking agent 147, arranges prism film 143 thereon, then irradiates second ultraviolet crosslinking agent 147 to each other A brightness enhancement film 142 and a prism film 143 are attached.

In addition, as described above, in order to integrally form the optical sheet portion 140, the following steps are carried out in a separate facility: providing the first ultraviolet crosslinking agent 146; uniformly coating the first crosslinking agent 146; On the ultraviolet crosslinking agent 146, the second ultraviolet crosslinking agent 147 is provided on the brightness enhancement film 142; the second ultraviolet crosslinking agent 147 is evenly coated; the prism film 143 is positioned on the second ultraviolet crosslinking agent 147, toward the first And the second ultraviolet crosslinking agent 146, 147 is irradiated with ultraviolet rays, but it is also possible to manufacture the integrated optical sheet part by performing a rolling and rocking continuous process on multiple parts on the long drum at the same time. (IY-200401-023-1)

10 is a cross-sectional view of a liquid crystal display including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention.

As shown in FIG. 10 , a liquid crystal display 100 including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention includes a display portion 130 , a backlight portion 145 located at the lower portion of the display portion and providing light to the display portion 130 , an intervening display portion 130 and the backlight part and the optical sheet part 140 that makes the brightness of the light from the backlight part 150 uniform. Also, the display part 130 is composed of a thin film transistor display panel 131 , a color filter display panel 132 facing the thin film transistor display part 131 , and a liquid crystal layer 135 injected between the display panels 131 , 132 thereof. Also, lower and upper polarizing plates 133, 134 are disposed outside the thin film transistor display panel 131 and the color filter display panel 132, respectively.

The backlight unit 150 has a plurality of lamps 151 that generate light, and a light guide plate 152 that guides the light from the lamps 151 to the display unit 130 . The lamp 151 shown in FIG. 10 is a direct type in which the lamp 151 is placed under the display portion 130 and the light guide plate 150 . The light guide plate 150 is located under the display part 130 and has a size corresponding to the display part 130 . As shown in FIG. 10 , the light guide plate 150 may have a uniform thickness, or its thickness may increase or decrease gradually.

On the upper part of the light guide plate 150, an optical sheet part 140 is arranged to make the brightness to the display part 130 uniform, and on the lower part of the backlight part 130, a reflective plate 160 is arranged to re-reflect the light reflected from the light guide plate 150 to improve the light efficiency.

The optical sheet unit 140 is composed of a plurality of optical sheets. That is, the optical sheet part 140 consists of a diffusion film 141 that diffuses the light generated in the backlight part 150 to make the brightness distribution uniform, a brightness enhancement film 142 that transmits the P wave in the light source and reuses the S wave to increase the brightness, and condenses light with a uniform distribution. The prism film 143 is composed of.

A brightness enhancement film 142 is formed on the diffusion film 141 , and a prism film 143 is formed on the brightness enhancement film 142 .

Such a diffusion film 141 and a brightness enhancement film 142 are attached through a first ultraviolet crosslinking agent 146, and a brightness enhancement film 142 and a prism film 143 are attached through a second ultraviolet crosslinking agent to integrally form the optical sheet part 140.

In this way, the diffusion film 141, the brightness enhancement film 142, and the prism film 143 are integrally formed to prevent a concave portion between the diffusion film 141, the brightness enhancement film 142, and the prism film 143 whose degrees of expansion vary depending on temperature and humidity.

The brightness enhancement film 142 includes a polymer film 144 and an optical crystal cuticle 245 formed on the polymer film 144 . Preferably, there is only one brightness enhancement film 142 .

Preferably, the polymer film 144 is polycarbonate, polyethylene terephthalate, polyimide, polyamide, polysulfone, polypropylene, polymethyl methacrylate, polypropylene, cellulose acetate, One of the polymers formed by the copolymerization of the above-identified polymers, or derivatives thereof.

As shown in FIG. 11A and FIG. 11B , a photocrystal colloidal layer 245 is composed of a plurality of photocrystal colloidal particles 10 and polymer resin 20 .

FIG. 11B shows a plurality of optical crystal colloids forming a 111 lattice and stacked on a polymer film, and FIG. 11B shows a plurality of optical crystal colloids forming a 100 lattice and stacking on a polymer film.

As shown in FIG. 11A and FIG. 11B , a plurality of optical crystal colloidal particles 10 form predetermined lattice structures such as 111, 100 or other crystal shapes and are stacked. Moreover, preferably, the size of the optical crystal colloidal particles 10 is several nanometers (nm) to hundreds of nanometers.

The polymer resin 200 is formed by hardening a polymer solution of the same material as the polymer film 144 , and serves to fix a plurality of optical crystal colloidal particles 10 .

The optical crystal layer 245 having a plurality of optical crystal colloidal particles 10 forming such a predetermined lattice structure has reflective polarization properties. That is, the P wave is transmitted and the S wave is reflected by a plurality of optical crystal colloidal particles 10 forming a predetermined lattice structure, thereby exhibiting reflective polarization characteristics.

That is, as shown in FIG. 10, FIG. 11A, and FIG. 11B, the light generated by the backlight unit 150 includes P waves and S waves, and according to the brightness enhancement film 142 having reflective polarization characteristics, the P waves are transmitted and the S waves are reflected, so only the P waves The waves are supplied to the display unit.

Therefore, for light having a wavelength of 250 to 800 nm, the brightness enhancement film 142 transmits P waves and reflects S waves. Moreover, the S wave reflected from the brightness enhancement film 142 is re-reflected by the reflector and becomes a P' wave and an S' wave, wherein the P' wave is transmitted and the S' is reflected by the brightness enhancement film 142 and then re-reflected by the reflector 160. reflection. Through this iterative process, the number of P waves passing through the photocrystal colloid 245 is increased to increase brightness.

Furthermore, by forming a plurality of brightness enhancement films 142 having such optical crystal colloid 245, the reflective polarization characteristics can be further improved.

The traditional brightness enhancement film 142 is stacked with more than hundreds of thin films, which has a thickness of 140 to 440 μm, so the manufacturing process is complicated, but the brightness enhancement film 142 according to the first embodiment of the present invention only uses a single layer or several layers with reflective polarizing properties Therefore, the thickness of the brightness enhancement film 142 is reduced while simplifying the manufacturing process.

A method of manufacturing the brightness enhancement film 142 for a liquid crystal display according to the present invention having the above structure will be described below with reference to FIGS. 12 to 14 .

First, as shown in FIG. 12 , a photocrystal colloid was produced using a reactor. The method for producing the photocrystalline colloid will be described in detail below.

About 450 g of deionized water, 0.3 g of sodium styrene sulfonate of softening agent or emulsifier, and a buffer (buffer), ie, 0.25 g of sodium hydrogen carbonate of polymerization agent, were put into the reactor 40 .

Then, while maintaining the temperature inside the reactor 40 at 80° C., the contents of the reactor 40 were stirred by rotating the stirrer 41 inside the reactor 40 at a speed of 350 rpm for about 10 minutes. That is, two or more substances having different physical or chemical properties are brought into a uniform mixed state using external mechanical force.

Then, 50 g of styrene monomer was charged into the reactor 40 . Then, 0.25 g of an initiator potassium persulfate 0.25 g was charged into the reactor 40 one hour later, and then a polymerization reaction was carried out in nitrogen for 18 hours to produce the optical crystal gum 50 .

At this time, the size of the optical crystal colloid 10 produced can be adjusted by adjusting the concentration ratio between the monomer and the softening agent.

Preferably, the optical crystal colloidal particle 10 of the present invention has a size ranging from tens of nanometers to hundreds of nanometers.

Next, a plurality of optical crystal colloidal particles 10 in the produced optical crystallization colloid 50 are stacked on the polymer film 144 .

To this end, as shown in FIG. 13A , firstly, the glass substrate 1 with the polymer film 144 attached is put into the container 2 containing the photocrystalline colloid 50 . That is, the glass substrate 1 with the polymer film 144 attached is vertically inserted into a container containing the photocrystal colloid 50 by dipping, so that the photocrystal colloid 50 is in contact with the polymer film 144 .

The polymer film 144 is polycarbonate, polyethylene terephthalate, polyimide, polyamide, polyether, polysulfone, polypropylene, polymethyl methacrylate, polypropylene, cellulose acetate, One of the polymers formed by the copolymerization of the above-identified polymers, or derivatives thereof.

Next, as shown in FIG. 13B, the glass substrate 1 with the polymer film 144 attached is taken out from the container 1 containing the optical crystallization colloid 50, and evaporated at an evaporation temperature of 4° C. to 100° C. Vacuum drying is carried out within an evaporation time of about 1 hour.

At this time, as shown in FIG. 13C , with the evaporation of organic solvent 30 such as water or ethanol contained in photocrystal colloid 50 , a plurality of photocrystal colloid particles 10 adhere to the surface of polymer film 144 . At this time, as shown in FIG. 4D , a plurality of optical crystal colloidal particles 10 are formed into a predetermined lattice structure and stacked.

Then, as shown in FIG. 11A and FIG. 11B , in order to keep the laminated optical crystal colloidal particles 10 attached to the surface of the polymer film 144, a high polymer film of the same material as the polymer film 144 is evenly coated on the polymer film 144. Molecular Resin 20. Therefore, as the polymer resin 20 hardens, a plurality of optical crystal colloids 10 form a predetermined lattice structure and are fixed on the surface of the polymer film 144 .

In this way, the reflective polarization property is realized by the first optical crystal colloid layer 245 composed of the laminated optical crystal colloidal particles 10 and the polymer resin 20 . That is, the predetermined lattice structure composed of the stacked optical crystal colloidal particles 10 exhibits reflective polarization characteristics.

That is, as shown in FIGS. 11A and 11B , the light generated by the backlight unit 150 includes P waves and S waves, and the P waves pass through the brightness enhancement film 142 having reflective polarization characteristics, and the S waves are reflected, thereby only the P waves supplied to the display unit.

Therefore, for light having a wavelength of 250 to 800 nm, the brightness enhancement film 142 transmits P waves and reflects S waves. Moreover, the S wave reflected by the brightness enhancement film 142 is reflected again by the reflector 160 into P′ wave and S′ wave, wherein the P′ wave is transmitted, and the S′ wave is reflected by the brightness enhancement film 142 and then reflected by the reflector 160 again. Repeating this process increases the number of P waves passing through the first photocrystal colloidal layer 245, increasing brightness.

Preferably, the method of uniformly coating the polymer resin 20 on the polymer film 144 includes a spin coating method, a blade installation method or a solution dipping method.

Moreover, in order to increase the reflective polarization characteristic of the brightness enhancement film 142 , a polymer film 144 and a second photo-crystal colloid layer 246 may be formed on the first photo-crystal colloid layer 245 .

FIG. 14 shows the formation state of the first and second optical crystal colloid layers 245 and 246 .

That is, the polymer film 162 is attached to the first photocrystal colloid layer 245, and the glass substrate forming the first photocrystal colloid layer 245 and the polymer film 164 is soaked in the photocrystal colloid.

Then, the glass substrate is pulled out from the photocrystal colloid, organic solvents such as water or ethanol are evaporated, and the second photocrystal colloid layer in which the photocrystal colloid particles 16 are stacked with a predetermined lattice structure is formed on the surface of the polymer film 164 246.

Then, the above steps are repeated to form a plurality of brightness enhancement films 142 .

A method of manufacturing a liquid crystal display including the brightness enhancement film 142 for a liquid crystal display of the present invention having the structure as described above will be described below with reference to FIGS. 6 to 7A and 16 .

First, as shown in FIG. 6 , a solution-like first ultraviolet crosslinking agent 146 is provided on the diffusion film 140 .

Then, as shown in FIGS. 7A and 7B , the first ultraviolet crosslinking agent 146 is uniformly coated on the diffusion film 141 .

That is, as shown in FIG. 7A, the first ultraviolet crosslinking agent 146 is uniformly coated with a certain thickness on the diffusion film 141 by using the spin coating method to rotate the diffusion film 141, or as shown in FIG. The diffusion film 141 is rotated, and the first ultraviolet crosslinking agent 146 is uniformly coated on the diffusion film 141 with a certain thickness by the roller 55 .

Then, as shown in FIGS. 15A and 15B , the brightness enhancement film is placed on the first ultraviolet crosslinking agent 146 . Preferably, the brightness enhancement film 142 includes an optical crystal colloid layer 245 formed on the polymer film 144 , and preferably, there are more than one of them. Moreover, the plurality of optical crystallization colloidal particles 10 of the optical crystallization colloidal layer 246 form a predetermined lattice structure, for example, form a 111 or 100 lattice structure.

The optical crystal colloid layer 245 having a plurality of optical crystal colloidal particles 10 constituting such a predetermined lattice structure has reflective polarization properties. Thus, the brightness enhancement film 142 transmits P waves and reflects S waves. Moreover, the S wave reflected from the brightness enhancement film 142 is re-reflected by the reflector to become a P' wave and an S' wave, wherein the P' wave is transmitted, and the S' is reflected by the brightness enhancement film 142 and then re-reflected by the reflector 160. reflection. Through this iterative process, the number of P waves passing through the photocrystal colloid 245 is increased to increase brightness.

Then, the second ultraviolet crosslinking agent 147 in the form of a solution is loaded on the brightness enhancement film 142 . Then, the second ultraviolet crosslinking agent 147 is uniformly coated on the diffusion film 141 .

That is, as shown in FIG. 15A, the second ultraviolet crosslinking agent 147 is evenly coated on the diffusion film 141 with a certain thickness by using the spin coating method to rotate the diffusion film 141, or as shown in FIG. In the film 141 , the second ultraviolet crosslinking agent 147 is uniformly coated on the diffusion film 141 with a constant thickness by the roller 55 .

Then, as shown in FIG. 16 , the prism film 143 is placed on the second ultraviolet crosslinking agent 147 . Then, ultraviolet light (UltraViolet, UV) is irradiated to the first and second ultraviolet crosslinking agents 146 and 147, and the diffusion film 141 and the brightness enhancement film 142 are adhered to each other with the first ultraviolet crosslinking agent 146, and the second ultraviolet crosslinking agent 147 is used to adhere to each other. The brightness enhancement film 142 and the prism film 143 are attached to each other.

In this way, the diffusion film 141, the brightness enhancement film 142, and the prism film 143 of the optical sheet portion 140 of the liquid crystal display are integrally formed to prevent recesses between the diffusion film 141, the brightness enhancement film 142, and the prism film 143.

As described above, the diffusion film, the brightness enhancement film 142 and the brightness enhancement film 142 and the prism film 143 are adhered while irradiating ultraviolet rays to the first and second ultraviolet crosslinking agents 146 and 147 at the same time, but they may be crosslinked to the first ultraviolet rays. After the agent 146 irradiates ultraviolet rays to adhere to the diffusion film 141 and the brightness enhancement film 142, apply the second ultraviolet crosslinking agent 147, place the prism film 143 on it, and then irradiate ultraviolet rays to the second ultraviolet crosslinking agent 147 to enhance the mutual adhesion and brightness. film 142 and prism film 143 .

As described above, in order to integrally form the optical sheet portion 140, the following steps are performed in a separate facility: providing the first ultraviolet crosslinking agent 146; uniformly coating the first crosslinking agent 146; On the linking agent 146, the second ultraviolet crosslinking agent 147 is provided on the brightness enhancement film 142; the second ultraviolet crosslinking agent 147 is uniformly coated; the prism film 143 is positioned on the second ultraviolet crosslinking agent 147, and the The two ultraviolet crosslinking agents 146 and 147 are irradiated with ultraviolet rays, but it is also possible to manufacture the integrated optical sheet part through a continuous process of simultaneously rolling and rocking a plurality of parts on the long drum. (IY-200401-013-1)

17 is a cross-sectional view of a liquid crystal display including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention.

As shown in FIG. 17 , the liquid crystal display 100 comprising the brightness enhancement film for liquid crystal display according to the first embodiment of the present invention includes: a display portion 130 for displaying images; Supply light; the optical sheet part is sandwiched between the display part 130 and the backlight part 150 to make the brightness of the light generated by the backlight part 150 uniform. Furthermore, the display unit 130 is composed of a thin film transistor (TFT, thin film transistor) display panel 131 , a color filter 132 facing the TFT display panel 131 , and a liquid crystal layer 135 injected between these display panels 131 and 132 . Moreover, lower and upper polarizers 133 and 134 are arranged on the outside of the TFT display panel 131 and the color filter 132 respectively.

The backlight unit 150 has a plurality of lamps 151 that generate light and a light guide plate 152 that guides light from the lamps 151 to the display unit 130 . As shown in FIG. 17 , the lamp is a direct type in which a lamp is arranged below the display unit 130 . The light guide plate 150 is located below the display part 130 and has a size corresponding to the display part 130 . As shown in FIG. 17 , the light guide plate 150 may have a uniform thickness, or may gradually increase or decrease the thickness.

In order to make the brightness of the light directed to the display part 130 uniform, an optical sheet is arranged on the upper part of the light guide plate 150, and a reflector is arranged on the lower part of the backlight part 130 to re-reflect the light reflected by the light guide plate 150 to the side of the light guide plate 150 to improve light efficiency. plate 160.

The optical sheet unit 140 is composed of a plurality of optical sheets. That is, the optical sheet part 140 diffuses the light generated by the backlight part 150 to make the brightness distribution uniform, the brightness enhancement film 142 that transmits the P wave in the light source and reuses the S wave to improve the brightness, and the condensing light will have a uniform brightness. The prism film 143 is composed of distributed light.

A brightness enhancement film 142 is formed on the diffusion film 141 , and a prism film 143 is formed on the brightness enhancement film 142 .

The diffusion film 141 and the brightness enhancement film 142 are attached by the first ultraviolet crosslinking agent 146, and the brightness enhancement film 142 and the prism film 143 are attached by the second ultraviolet crosslinking agent 147, thereby forming an integrated optical sheet.

The diffusion film, brightness enhancement film 142 and prism film 143 are integrally formed to prevent recesses between the diffusion film 141 , brightness enhancement film 142 and prism film 143 whose degrees of expansion vary depending on temperature and humidity.

Fig. 18 shows a perspective view and a partially enlarged view of a brightness enhancement film.

As shown in FIG. 18 , preferably, the brightness enhancement film 142 is a polymer film 76 containing metal ion particles 75 , and the metal ion particles 75 are Ag ⁺ , Cu ²⁺ . Moreover, the metal ion particles 75 form a predetermined lattice structure in the polymer film 76 , such as a face centered cubic lattice structure (face centered cubic, FCC).

The polymer film 76 is polycarbonate, polyethylene terephthalate, polyimide, polysulfone, polymethyl methacrylate, polystyrene, polyvinyl chloride, polyvinyl alcohol, polynorbornene , a polymer formed by the copolymerization of the above-identified polymers, or one of its derivatives.

The brightness enhancement film 142 that becomes the polymer film 76 including the plurality of metal ion particles 75 having such a predetermined lattice structure has reflective polarization characteristics. That is, through the plurality of metal ion particles 75 with a predetermined lattice structure, the P wave is passed and the S wave is reflected, so as to reflect the reflective polarization characteristic.

As shown in FIG. 17 , the light generated by the backlight unit 150 includes P waves and S waves, and through the brightness enhancement film 142 having reflective polarization properties, the P waves are passed and the S waves are reflected, and only the P waves are provided to the display unit.

Thus, the brightness enhancement film 142 transmits P-waves and reflects S-waves for light having a wavelength of 250 to 800 nm. Moreover, the S wave reflected from the brightness enhancement film 142 is re-reflected by the reflector to become a P' wave and an S' wave, wherein the P' wave is transmitted, and the S' is reflected by the brightness enhancement film 142 and then re-reflected by the reflector 160. reflection. Through this repeated process, the number of P waves passing through the photocrystal colloid 245 is increased to increase brightness.

Moreover, thermally stretching the brightness enhancement film 142 in a predetermined direction can further improve the reflective polarization characteristics of the brightness enhancement film 142 . That is, a predetermined lattice structure composed of metal ion particles 75 is arranged in the extending direction, thereby producing a difference in refractive index between the extending direction and the non-extending direction, so as to further improve the reflective polarization characteristic.

Preferably, the thermally stretched brightness enhancement film 142 has a length greater than 1.1 to 8 times the length before thermal stretching.

The traditional brightness enhancement film 142 is laminated with more than hundreds of thin films, has a thickness of 140 to 440 μm, and its manufacturing process is complicated. Polarizing properties, so the thickness of the brightness enhancement film 142 is thin, which simplifies the manufacturing process.

Next, a method for manufacturing the brightness enhancement film 142 for a liquid crystal display according to the present invention having the above structure will be described in detail with reference to FIGS. 19 to 21 and 23 .

First, as shown in FIG. 19 , a polymer resin solution 142 containing metal ions is loaded on a glass substrate 4 .

The polymer resin solution 142 containing metal ions is a mixed solution of materials containing metal ions such as AgCl and CuCl ₂ and polymer resins with acid radicals.

Polymer resins with acid radicals are polycarbonate, polyethylene terephthalate, polyimide, polysulfone, polymethyl methacrylate, polystyrene, polyvinyl chloride, polyvinyl alcohol, One of bornene, a polymer formed by copolymerization of the above-identified polymers, or a derivative thereof.

Then, as shown in FIG. 20A and FIG. 20B , the polymer resin solution 142 containing metal ions is evenly coated on the glass substrate 4 by using the spin coating method or the blade mounting method.

As shown in Figure 20A, the spin coating method is to rotate the glass substrate 4 to uniformly coat the polymer resin solution 142 containing metal ions with a certain thickness. The ionic polymer resin solution 142 is uniformly coated with a certain thickness.

Then, as shown in FIG. 21 , the polymer resin solution 142 containing metal ions is dried to form a polymer film 142 . That is, drying is performed at a temperature of 4° C. to 100° C., preferably, on a hot metal plate of 40° C. to 200° C. to form a polymer film 142 containing metal ions 75 .

At this time, the polymer resin with acid radicals in the polymer resin solution is separated into water (H ₂ O) molecules according to the dehydration reaction of the acid radicals, and the metal ions are reduced to attach to the polymer resin to become the predetermined composition of metal ions in the polymer resin. lattice and dispersed state.

That is, when the polymer resin solution 145 containing metal ions is dried, the metal ions are reduced to be dispersed and arranged in the polymer film 142 as metal ion particles 75 having a size of nm.

Reflective polarization characteristics are realized based on the metal ion particles 75 constituting a predetermined lattice and arranged in a dispersed manner.

22A is a chemical formula of a polymer resin having an acid group, and FIG. 22B is a chemical formula of a polyimide formed by a dehydration reaction when the polymer resin is dried.

Then, as shown in FIG. 23, the polymer film, that is, the brightness enhancement film 142 is thermally stretched in a certain direction, that is, in the X direction.

Preferably, the heat stretching treatment temperature is from the glass transition temperature of the polymer film 144 to the glass transition temperature+100° C. Preferably, the length of the brightness enhancement film 142 after thermal stretching is 1.1 to 8 times longer than that before thermal stretching.

Here, the glass transition temperature of the polymer film 142 refers to the temperature at which the Brownian motion of the particles of the polymer film 142 is most active, and as the glass transition temperature of the polymer film 142 is exceeded, the polymer film 142 is easily thermally stretched. For example, polyethylene terephthalate PET has a glass transition temperature of about 75°C.

In this way, thermal stretching is performed to increase the size of the metal ion particles 75 in the polymer film along the X direction to make the polarization more favorable. That is, a predetermined lattice composed of metal ion particles 75 is arranged long along the thermally stretched direction, so that a difference in refractive index occurs between the thermally stretched direction and the non-stretched direction, thereby further improving the reflective polarization characteristic. Improve the reflected polarized light characteristics of the transmitted P wave and reflected S wave, which is recycled through the reflector, thereby increasing the number of P waves passing through the polymer film and increasing the brightness.

FIG. 24 illustrates another method of manufacturing a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention.

Here, the same reference numerals as above refer to the same components having the same functions.

As shown in FIG. 24, the powdery polymer resin 33 and the powdery metal particles 99 are molded by casting at a temperature between the glass transition temperature and the glass transition temperature+180°C.

The casting molding process is to distribute metal particles with a size of several nanometers (nm) in the liquid polymer resin obtained by melting the polymer resin 33 and powdered metal particles 99 in a high-temperature container, and use a cooling drum 66 at 100°C to 1400°C A process of manufacturing the polymer film 142 .

At this time, the metal particles 75 form a predetermined lattice structure, that is, a face-centered cubic lattice structure (FCC) and are distributed in the polymer film 142, and the brightness enhancement film realizes reflective polarization characteristics according to this predetermined lattice structure.

Preferably, the metal particles 75 are gold (Au) particles or silver (Ag) particles with a size of several nanometers, and the polymer resin is polycarbonate, polyethylene terephthalate, polyimide, polysulfone, polymethane methyl acrylate, polystyrene, polyvinyl chloride, polyvinyl alcohol, polynorbornene, a polymer formed by copolymerization of the above-identified polymers, or a derivative thereof.

Moreover, preferably, the concentration of the polymer resin is between about 70wt% and 99.9wt%, and the concentration of the metal particles is between about 0.1wt% and 30wt%.

This other manufacturing method of brightness enhancement film for liquid crystal display uses gold or silver directly than the above-mentioned one manufacturing method, which has the disadvantage of cost increase, but can form a predetermined crystal lattice based on metal particles more favorably, It has the advantage of improving the reflective polarization characteristics.

At this time, as shown in FIG. 23, the brightness enhancement film 142 is thermally stretched in a predetermined direction, that is, the X direction, so that the size of the predetermined lattice composed of metal ion particles 75 in the polymer film increases along the X direction, Even better with polarized light. That is, a predetermined lattice composed of metal ion particles 75 is arranged long along the thermal stretching direction, so that a difference in refractive index occurs between the stretching direction and the non-stretching direction, so as to further improve the reflective polarization characteristic.

A method of manufacturing a liquid crystal display device including the brightness enhancement film 142 for a liquid crystal display according to the present invention having the above structure is described with reference to FIGS. 6 to 7B and FIGS. 25A to 26 .

First, as shown in FIG. 6 , a solution-like first ultraviolet crosslinking agent 146 is provided on the diffusion film 141 .

Then, as shown in FIGS. 7A and 7B , the first ultraviolet crosslinking agent 146 is uniformly coated on the diffusion film 141 .

That is, as shown in FIG. 7A, the first ultraviolet crosslinking agent 146 is evenly coated with a certain thickness on the diffusion film 141 by using the spin coating method to rotate the diffusion film 141, or as shown in FIG. The diffusion film 141 is rotated, and the first ultraviolet crosslinking agent 146 is uniformly coated on the diffusion film 141 with a certain thickness by the roller 55 .

Then, as shown in FIGS. 25A and 25B , the brightness enhancement film is placed on the first ultraviolet crosslinking agent 146 . Preferably, the brightness enhancement film 142 is a polymer film containing metal ion particles 75, and the metal ion particles 75 are Ag ⁺ , Cu ²⁺ . Furthermore, such metal ion particles 75 form a predetermined lattice structure in the polymer film, for example, form a face centered cubic lattice structure (face centered cubic, FCC).

A polymer film containing a plurality of metal ion particles 75 having such a predetermined lattice structure has reflective polarization properties. That is, P waves are passed through a plurality of metal ion particles 75 forming a predetermined lattice structure, and S waves are reflected to realize reflective polarization characteristics.

Thus, for light having a wavelength of 250 to 800 nm, the brightness enhancement film 142 transmits P waves and reflects S waves. Moreover, the S wave reflected from the brightness enhancement film 142 is re-reflected by the reflector to become a P' wave and an S' wave, wherein the P' wave is transmitted, and the S' is reflected by the brightness enhancement film 142 and then re-reflected by the reflector 160. reflection. Through this iterative process, the number of P waves passing through the photocrystal colloid 245 is increased, and the brightness is improved.

Then, a solution-like second ultraviolet crosslinking agent 147 is loaded on the brightness enhancement film 142 . Then, the second ultraviolet crosslinking agent 147 is uniformly coated on the diffusion film 141 .

That is, as shown in FIG. 25A, the second ultraviolet crosslinking agent 147 is uniformly coated on the diffusion film 141 with a certain thickness by using the spin coating method to rotate the diffusion film 141, or as shown in FIG. In the film 141 , the second ultraviolet crosslinking agent 147 is uniformly coated on the diffusion film 141 with a constant thickness by the roller 55 .

Then, as shown in FIG. 26 , the prism film 143 is placed on the second ultraviolet crosslinking agent 147 . Then, ultraviolet light (UltraViolet, UV) is irradiated to the first and second ultraviolet crosslinking agents 146 and 147, the diffusion film 141 and the brightness enhancement film 142 are adhered with the first ultraviolet crosslinking agent 146, and the second ultraviolet crosslinking agent 147 is attached. Brightness enhancement film 142 and prism film 143 .

In this way, the diffusion film 141 , the brightness enhancement film 142 and the prism film 143 of the optical sheet portion 140 of the liquid crystal display are integrally formed to prevent recesses between the diffusion film 141 , the brightness enhancement film 142 and the prism film 143 .

As described above, the diffusion film 141, the brightness enhancement film 142, the brightness enhancement film 142, and the prism film 143 are adhered while irradiating ultraviolet rays to the first and second ultraviolet crosslinking agents 146, 147 simultaneously, but it is also possible to first crosslink the first ultraviolet crosslinking agent 146, 147. After irradiating the UV adhesion diffusion film 141 and the brightness enhancement film 142 with the UV agent 146, apply the second UV crosslinking agent 147, place the prism film 143 on it, and then irradiate the UV adhesion brightness enhancement film to the second UV crosslinking agent 147. 142 and prism film 143.

In addition, as described above, in order to integrally form the optical sheet portion 140 in a separate facility, the following steps are performed: providing the first ultraviolet crosslinking agent 146; uniformly coating the first crosslinking agent 146; making the brightness enhancement film 142 is located on the first ultraviolet crosslinking agent 146, and the second ultraviolet crosslinking agent 147 is provided on the brightness enhancement film 142; the second ultraviolet crosslinking agent 147 is evenly coated; the prism film 143 is positioned on the second ultraviolet crosslinking agent 147 The first and second ultraviolet crosslinking agents 146 and 147 are irradiated with ultraviolet rays, but the integrated optical sheet part can also be manufactured through a continuous process of simultaneously rolling and rocking a plurality of parts on the long drum. (IY-200401-017-1)

27 is a cross-sectional view of a liquid crystal display including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention.

As shown in FIG. 27 , the liquid crystal display 100 comprising the brightness enhancement film for liquid crystal display according to the first embodiment of the present invention includes: a display part 130 for displaying images; 130 provides light; the optical sheet part 140 is sandwiched between the display part 130 and the backlight part 150 to make the light generated by the backlight part 150 uniform. Also, the display section 130 is composed of a thin film transistor display panel 131 , a color filter 132 facing the thin film transistor display panel 131 ; and a liquid crystal layer 135 injected between these display panels 131 , 132 . Moreover, lower and upper polarizers 133 and 134 are arranged outside the TFT display panel 131 and the color filter 132 respectively.

The backlight unit 150 has a plurality of lamps 151 that generate light and a light guide plate 152 that guides the light from the lamps 151 to the display unit 130 . The lamp shown in FIG. 27 is a direct type in which a lamp is arranged below the display portion 130 . The light guide plate 150 is located below the display part 130 and has a size corresponding to the display part 130 . As shown in FIG. 27, the light guide plate 150 may have a uniform thickness, or may have a gradually increasing or decreasing thickness.

The upper part of the light guide plate 150 is arranged with the optical sheet part 140 to make the brightness of the light incident on the display part 130 uniform, and the lower part of the backlight part 130 is arranged with the reflection plate 160 to re-reflect the light reflected by the light guide plate 150 to improve the light efficiency.

The optical sheet unit 140 is composed of a plurality of optical sheets. That is, the optical sheet part 140 diffuses the light produced by the backlight part 150 to make the brightness distribution uniform; the P wave in the transmission light source and reuses the S wave to improve the brightness enhancement film (brightnessenhancement film) 142 of the brightness; A prism film (prism film) 143 is composed of uniformly distributed light condensing.

A brightness enhancement film 142 is formed on the diffusion film 141 , and a prism film 143 is formed on the brightness enhancement film 142 .

The diffusion film 141 and the brightness enhancement film 142 are attached through the first ultraviolet crosslinking agent 146, and the brightness enhancement film 142 and the prism film 143 are attached through the second ultraviolet crosslinking agent 147, thereby forming an optical sheet integrally.

In this way, the diffusion film, brightness enhancement film 142 and prism film 143 are integrally formed to prevent recesses between the diffusion film 141 , brightness enhancement film 142 and prism film 143 whose degrees of expansion vary depending on temperature and humidity.

FIG. 31 shows the sequence of a method of manufacturing a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention.

As shown in FIGS. 27 and 31 , the brightness enhancement film 142 includes a polymer film 144 and a liquid crystal layer 345 formed on the polymer film 144 . Preferably, there is only one brightness enhancement film 142 .

Polymer film 144 is polycarbonate, polyethylene terephthalate, polysulfone, polymethyl methacrylate, polystyrene, polyvinyl chloride, polyvinyl alcohol, polynorbornene, determined by the above A polymer formed by copolymerization of a polymer, or one of its derivatives.

There are a plurality of encapsulated liquid crystal molecules 9 in the liquid crystal layer 345 , and the encapsulated liquid crystal molecules 9 have a microcrystalline structure. That is, as shown in FIG. 28 , the polymer particles 4 respectively surround the liquid crystal molecules 8 to form fine crystals. The liquid crystal molecules in which the polymer particles 4 respectively surround the liquid crystal molecules 8 are called encapsulated liquid crystal molecules. The liquid crystal molecules are respectively surrounded with the meltable part of the polymer particle 4 facing outward and the non-meltable part of the polymer particle 4 facing inward. Then, a plurality of encapsulated liquid crystal molecules 9 are aligned parallel to a certain direction.

Preferably, such encapsulated liquid crystal molecules 9 have a size of more than tens of nanometers and less than hundreds of nanometers.

The encapsulated liquid crystal molecules 9 of this tiny crystal structure are all aligned in a predetermined direction in the liquid crystal layer 345, through the optical anisotropy of the liquid crystal molecules 9, the P wave is passed, while the S wave is reflected, so as to have reflective polarization characteristics .

That is, as shown in FIG. 27 , the light generated by the backlight unit 150 includes P waves and S waves, and through the brightness enhancement film 142 having reflective polarization properties, the P waves are passed, the S waves are reflected, and only the P waves are supplied to the Display section.

Therefore, for light having a wavelength of 250 to 800 nm, the brightness enhancement film 142 transmits P waves and reflects S waves. Moreover, the S wave reflected from the brightness enhancement film 142 is re-reflected by the reflector to become a P' wave and an S' wave, wherein the P' wave is transmitted, and the S' is reflected by the brightness enhancement film 142 and then re-reflected by the reflector 160. reflection. Through this iterative process, the number of P waves passing through the photocrystal colloid 245 is increased to increase brightness.

Also, a plurality of brightness enhancement films 142 having such a liquid crystal layer 345 are formed to further improve reflective polarization characteristics.

Moreover, thermally stretching the brightness enhancement film 142 in a certain direction can further improve the reflective polarization characteristics of the brightness enhancement film 142 . That is, the long axes of the liquid crystal molecules 9 are long aligned in the stretching direction, and a difference in refractive index occurs between the stretching direction and the non-stretching direction, thereby further improving the reflective polarization characteristic.

Preferably, the thermally stretched brightness enhancement film 142 has a length greater than 1.1 to 8 times the length before thermal stretching.

The traditional brightness enhancement film 142 is laminated with more than hundreds of layers of films, which has a thickness of 140 to 440 μm, so its manufacturing process is complicated, but the brightness enhancement film 142 according to the first embodiment of the present invention only uses a single layer or several layers with reflective polarized light. Therefore, the thickness of the brightness enhancement film 142 becomes thinner, which simplifies the manufacturing process.

A method of manufacturing a brightness enhancement film for a liquid crystal display according to the present invention having the structure as described above will be described below with reference to FIGS. 29 to 32 .

First, as shown in FIG. 29 , a reactor is used to manufacture a liquid crystal in which a plurality of liquid crystal molecules are encapsulated. A method of manufacturing a liquid crystal in which liquid crystal molecules are encapsulated will be described in detail below.

Add about 450 g of deionized water and 0.3 g of softener or emulsifier sodium styrene sulfonate into the reactor 40 .

Then, while maintaining the temperature inside the reactor 40 at 80 degrees, the stirrer 41 inside the reactor 40 was rotated at a speed of 350 rpm for about 10 minutes to stir the contents of the reactor inside 40 . That is, two or more substances having different physical or chemical properties are brought into a uniform mixed state using external mechanical force.

Then, 50 g of styrene monomer and nematic or smectic liquid crystals were charged into the reactor 40 . Then, 0.25 g of an initiator potassium persulfate (potassium persulfate) was charged into the reactor 40 one hour later, and then a polymerization reaction was performed in nitrogen for 3 hours to produce the optical crystal gel 50 . The liquid crystal 50 constituting such encapsulated liquid crystal molecules is in a colloidal state.

At this time, as shown in FIG. 28 , as polymer particles 4 of styrene monomer surround liquid crystal molecules, colloidal particles (Micell) are formed.

Preferably, the encapsulated liquid crystal molecules of the present invention have a size of not less than tens of nanometers but not more than hundreds of nanometers.

Then, as shown in FIG. 30 , the liquid crystal having encapsulated liquid crystal molecules manufactured as above is coated on the polymer film 144 to form a liquid crystal layer 345 . At this time, the alignment directions of the encapsulated liquid crystal molecules 9 are a plurality of directions.

Polymer film 144 is polycarbonate, polyethylene terephthalate, polysulfone, polymethyl methacrylate, polystyrene, polyvinyl chloride, polyvinyl alcohol, polynorbornene, determined by the above A polymer formed by copolymerization of a polymer, or one of its derivatives.

Then, as shown in FIG. 31 , the liquid crystal layer 345 coated on the polymer film 144 is rubbed or an electric field is applied to unify the alignment direction of each encapsulated liquid crystal molecule 9 to a certain direction.

In this way, reflective polarization characteristics are realized by the liquid crystal layer 345 composed of liquid crystal molecules 9 aligned in a certain direction. That is, reflective polarization characteristics are realized by utilizing the optical anisotropy of the plurality of encapsulated liquid crystal molecules 9 .

That is, as shown in FIG. 27 , the light generated by the backlight unit 150 includes P waves and S waves, and through the brightness enhancement film 142 having reflective polarization characteristics, the P waves are passed, the S waves are reflected, and only the P waves are supplied to the display portion. .

Thus, for light having a wavelength of 250 to 800 nm, the brightness enhancement film 142 transmits P waves and reflects S waves. Moreover, the S wave reflected from the brightness enhancement film 142 is re-reflected by the reflector to become a P' wave and an S' wave, wherein the P' wave is transmitted, and the S' wave is reflected by the brightness enhancement film 142 and is then reflected by the reflector 160. re-reflect. Through this iterative process, the number of P waves passing through the photocrystal colloid 245 is increased, and the brightness is improved.

Also, a plurality of brightness enhancement films 142 can be formed by repeating the above-mentioned steps.

Then, as shown in FIG. 32 , the brightness enhancement film 142 composed of the polymer film 144 and the liquid crystal layer 345 is thermally stretched in a certain direction, that is, in the X direction.

Preferably, the temperature for heat stretching is between the glass transition temperature of the polymer film 144 and the glass transition temperature+100° C. Preferably, the length of the brightness enhancement film 142 after thermal stretching is 1.1 to 8 times of the length before thermal stretching.

Here, the glass transition temperature ratio of the polymer film 144 represents the temperature at which the Brownian motion of the particles of the polymer film 144 is most active, and the temperature at which the polymer film 144 is most likely to be thermally stretched exceeds the glass transition temperature of the polymer film 144. state. For example, the glass transition temperature of polyethylene resin film PET is about 75 degrees.

In this way, thermal stretching is performed to increase the lattice size of the liquid crystal layer 345 in the X direction, thereby making the polarization more complete. That is, by aligning the long axes of the liquid crystal molecules 9 long in the stretching direction, a difference in refractive index occurs between the stretching direction and the non-stretching direction, and the reflective polarization characteristic is further improved. Improve the reflective polarization characteristics of the transmitted P wave, reflected S wave and then recycled through the reflective plate, so as to increase the number of P waves passing through the liquid crystal layer 345 and increase the brightness.

A method of manufacturing a liquid crystal display including the reinforcing film 142 for a liquid crystal display of the present invention having the structure described above will be described with reference to FIGS. 6 to 7B and FIGS. 33A to 34 .

First, as shown in FIG. 6 , the first ultraviolet crosslinking agent 146 in the form of a solution is supported on the diffusion film 140 .

Then, as shown in FIGS. 7A and 7B , the first ultraviolet crosslinking agent 146 is uniformly coated on the diffusion film 141 .

That is, as shown in FIG. 7A, the first ultraviolet crosslinking agent 146 is uniformly coated on the diffusion film 141 with a certain thickness by using the spin coating method to rotate the diffusion film 141, or as shown in FIG. For the film 141 , the first ultraviolet crosslinking agent 146 is uniformly coated on the diffusion film 141 with a certain thickness by the roller 55 .

Then, as shown in FIGS. 33A and 33B , the brightness enhancement film 142 is placed on the first ultraviolet crosslinking agent 146 . The brightness enhancement film 142 is composed of a polymer film 144 and a liquid crystal layer 345 formed on the polymer film 144 , preferably, there are more than one. Moreover, the plurality of encapsulated liquid crystal molecules 9 in the liquid crystal layer 345 are all aligned parallel to a certain direction.

The liquid crystal layer 345 has reflective polarization properties due to the optical anisotropy of the liquid crystal molecules 9 aligned parallel to a certain direction. Thus, for light having a wavelength of 250 to 800 nm, the brightness enhancement film 142 transmits P waves and reflects S waves. Moreover, the S wave reflected from the brightness enhancement film 142 is re-reflected by the reflector to become a P' wave and an S' wave, wherein the P' wave is transmitted, and the S' is reflected by the brightness enhancement film 142 and then re-reflected by the reflector 160. reflection. Through this iterative process, the number of P waves passing through the photocrystal colloid 245 is increased to increase brightness.

Then, a solution-like second ultraviolet crosslinking agent 147 is loaded on the brightness enhancement film 142 . Then, the second ultraviolet crosslinking agent 147 is uniformly coated on the diffusion film 141 .

That is, as shown in FIG. 33A, the second ultraviolet crosslinking agent 147 is uniformly coated on the diffusion film 141 with a certain thickness by using the spin coating method to rotate the diffusion film 141, or as shown in FIG. In the film 141 , the second ultraviolet crosslinking agent 147 is uniformly coated on the diffusion film 141 with a constant thickness by the roller 55 .

Then, as shown in FIG. 34 , the prism film 143 is placed on the second ultraviolet crosslinking agent 147 . Then, ultraviolet light (UltraViolet, UV) is irradiated to the first and second ultraviolet crosslinking agents 146 and 147, and the diffusion film 141 and the brightness enhancement film 142 are adhered to each other with the first ultraviolet crosslinking agent 146, and the second ultraviolet crosslinking agent 147 is used to adhere to each other. The brightness enhancement film 142 and the prism film 143 are attached to each other.

In this way, the diffusion film 141 , the brightness enhancement film 142 and the prism film 143 of the optical sheet portion 140 of the liquid crystal display are integrally formed to prevent recesses between the diffusion film 141 , the brightness enhancement film 142 and the prism film 143 .

As described above, the first and second ultraviolet crosslinking agents 146, 147 are irradiated with ultraviolet light at the same time to attach the diffusion film, the brightness enhancement film 142, and the brightness enhancement film 142 and the prism film 143. 146 After irradiating ultraviolet rays to attach the diffusion film 141 and the brightness enhancement film 142 to each other, apply the second ultraviolet crosslinking agent 147, place the prism film 143 on it, and irradiate ultraviolet rays to the second ultraviolet crosslinking agent 147 to attach the brightness enhancement film to each other. 142 and prism film 143.

In addition, as described above, in order to integrally form the optical sheet portion 140 in a separate facility, the following steps are performed: providing the first ultraviolet crosslinking agent 146; uniformly coating the first crosslinking agent 146; making the brightness enhancement film 142 is located on the first ultraviolet crosslinking agent 146, and the second ultraviolet crosslinking agent 147 is provided on the brightness enhancement film 142; the second ultraviolet crosslinking agent 147 is evenly coated; the prism film 143 is positioned on the second ultraviolet crosslinking agent 147 The first and second ultraviolet crosslinking agents 146 and 147 are irradiated with ultraviolet rays, but the integrated optical sheet part can also be manufactured through a continuous process of simultaneously rolling and rocking a plurality of parts on the long drum. (IY-200401-024-1)

35 is a cross-sectional view of a liquid crystal display including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention.

As shown in FIG. 35 , a liquid crystal display 100 including a brightness enhancement film for a liquid crystal display according to an embodiment of the present invention includes a display portion 130 displaying an image, and a backlight portion 145 located under the display portion 130 and providing light to the display portion. . The optical sheet 140 is interposed between the display unit and the backlight unit 150 to make the brightness of the light generated by the backlight uniform. Furthermore, the display unit 130 is composed of a film-coated transistor display panel 131 , a color filter display panel 132 of the multi-thin film transistor display panel 131 , and a liquid crystal layer 135 interposed therebetween. Also, lower and upper polarizing plates 133, 134 are disposed outside the thin film transistor display panel 131 and the color filter display panel 132, respectively.

The backlight unit 150 has a plurality of lamps 151 that generate light, and a light guide plate 152 that guides the light from the lamps 151 to the display unit. The lamp 151 shown in FIG. 1 is a direct type in which the lamp 151 is placed under the display portion 130 and the light guide plate 150 . The light guide plate 150 is located under the display part and has a size corresponding to the display part 130 . As shown in FIG. 1 , the light guide plate 150 has a uniform thickness, and the thickness can also be increased or decreased gradually.

On the light guide plate 150, an optical sheet portion 140 is arranged to make the luminance uniform to the display portion 130, and a reflection plate 160 is placed on the lower part of the backlight portion 130 to re-reflect the light reflected on the light guide plate 150 to improve the light efficiency.

The optical sheet 140 is composed of multiple optical sheets. That is, the optical sheet part 140 consists of a diffusion film 141 that diffuses the light generated by the backlight to make the brightness distribution uniform, a brightness enhancement film 142 that transmits P waves in the light source to make S reuse to improve brightness, and a prism film 143 that condenses light with uniform distribution. composition.

A brightness enhancement film 142 is formed on the diffusion film 141 , and a prism film 143 is formed on the brightness enhancement film 142 .

The diffusion film 141 and the brightness enhancement film 142 are attached by the first ultraviolet crosslinking agent 146 , and the brightness enhancement film 142 and the prism film 143 are attached by the second ultraviolet crosslinking agent 147 to form the integrated optical sheet 140 .

In this way, the diffusion film 141, the brightness enhancement film 142, and the prism film 143 are integrally formed to prevent a concave portion between the diffusion film 141, the brightness enhancement film 142, and the prism film 143 whose degrees of expansion vary depending on temperature and humidity.

36 and 37 show a perspective view of a brightness enhancement film and an organic ion chemical test, respectively.

As shown in FIGS. 36 and 37 , the brightness enhancement film 142 is a polymer film containing organic particles 79 with a core-shell structure, and the organic particles 79 with a core-shell structure are composed of methacrylate-butadiene-styrene.

In the core-shell structure, the core part is the cross-linked part of butadiene and styrene, and the shell part is the part around the core part surrounded by plexiglass.

That is, butadiene and styrene are connected to each other in a network structure, and plexiglass surrounds the butadiene and styrene periphery of this network structure.

In Figure 37, Sty refers to styrene, BuD refers to butadiene, and acrylate refers to methacrylate and methyl methacrylate.

The brightness enhancement film 142 is heat-treated in a certain direction, so the refractive index is generated between the heat-extended direction of the core-shell structure organic particles 79 and the non-thermally-extended direction to reflect reflected polarized light. That is, the organic particles with an extended core-shell structure transmit P waves and reflect S waves to reflect reflective polarization characteristics.

The thermally stretched brightness enhancement film 142 is 1.1 to 8 times longer than the non-thermally stretched length.

As shown in FIG. 35 , the light generated by the backlight unit 150 includes P waves and S waves, the P waves are transmitted and the S waves are reflected by the brightness enhancement film 142 having reflective properties, and only the P waves are supplied to the display unit.

Therefore, the brightness enhancement film 142 transmits P waves and reflects S waves for a wavelength of 250 to 800 nm. Moreover, the S wave reflected by the brightness enhancement film 142 is reflected again by the reflector 160, and becomes a P' wave and an S' wave, wherein the P' wave is transmitted, and the S' wave is reflected on the brightness enhancement film 142, and is reflected again by the reflector . This process is repeated to increase the amount of P waves passing through the brightness enhancement film 142 of the polymer film containing the core-shell organic particles 79 to increase the brightness.

The traditional brightness enhancement film 142 is stacked with hundreds of layers of thin films, and its thickness is 140 to 440 μm, so the manufacturing process is complicated, but the brightness enhancement film 142 of an embodiment of the present invention only uses a single layer or several layers with reflective polarization properties, so the brightness The enhancement film 142 is thin, which simplifies the manufacturing process.

A method of manufacturing the brightness enhancement film 142 for a liquid crystal display according to the present invention having the structure as described above will be described below with reference to FIGS. 38 to 39 .

As shown in FIG. 38 , the powdered polymer resin 33 and the powdered organic particles 79 with a core-shell structure are casted from the glass transition temperature to the glass transition temperature + 180 degrees.

The gradual molding process is to melt the powdery polymer resin 33 and the powdery organic particles 79 in the high-temperature container 33, so that the core-shell structure organic particles 79 are melted and dispersed in the liquefied polymer resin, and the drum 66 is cooled by 100°C to 140°C, To manufacture the polymer film 142 process.

At this time, as shown in FIG. 39 , core-shell organic ions 79 composed of methacrylate-butadiene-styrene are dispersed in the polymer film 142 .

Preferably, the polymer film is polycarbonate, polyethylene terephthalate, polysulfone, polymethyl methacrylate, polystyrene, polyvinyl chloride, polyvinyl alcohol, polynorbornene, from the above A polymer formed by the copolymerization of a defined polymer, or one of its derivatives.

Preferably, the concentration of the polymer resin is between about 70wt% and 99wt%, and the concentration of the organic particles is between about 1wt% and 30wt%.

Next, as shown in FIG. 40 , the brightness enhancement film is heat-treated in a certain direction, that is, in the X direction to enlarge the X direction of the organic particles 79 in the polymer film to achieve polarization. That is, the brightness enhancement film exhibits reflective polarization characteristics through the difference in refractive index between the extending direction and the non-extending direction of the core-shell organic particles 79 .

Next, a method of manufacturing a liquid crystal display including the brightness enhancement film 142 for a liquid crystal display of the present invention having the structure described above will be described with reference to FIGS. 6 to 7B and FIGS. 41 to 42A.

First, as shown in FIG. 6 , a first ultraviolet crosslinking agent 146 in a liquid state is carried on the diffusion film 141 .

Next, as shown in FIGS. 7A and 7B , the first ultraviolet crosslinking agent 146 is evenly coated on the diffusion film 141 .

That is, as shown in FIG. 7A, the diffusion film 141 is rotated by the spin coating method, and the first ultraviolet crosslinking agent 146 is evenly coated with a certain thickness on the diffusion film 141, or as shown in FIG. 7B, the blade method is used to rotate the diffusion film. 141 , uniformly coat the first ultraviolet crosslinking agent with a certain thickness on the diffusion film 141 by using the roller 55 .

Next, as shown in FIGS. 41A and 41B , the brightness enhancement film 142 is disposed on the first ultraviolet crosslinking agent 146 . The brightness enhancement film 142 is a polymer film containing the core-shell organic particles 79 , and has a refractive index difference between the stretched direction and the non-stretched direction.

The polymer film containing such extended core-shell organic particles 79 has reflective polarization properties. That is, the optically anisotropic core-shell organic particle 79 transmits the P wave and reflects the S wave, so as to exhibit reflective polarization characteristics.

Accordingly, brightness enhancement film 142 transmits P waves and reflects S waves. Moreover, the S wave reflected by the brightness enhancement film 141 is reflected by the reflector 160 into a P' wave and an S' wave, wherein the P' wave is transmitted, and the S' wave is reflected by the enhancement film 142, and is re-transmitted by the reflector 160. reflection. Repeating this process increases the amount of P waves passing through the brightness enhancement film 142, increasing the brightness.

Furthermore, a liquid second ultraviolet crosslinking agent 147 is carried on the brightness enhancement film 142 . The second ultraviolet crosslinking agent 147 is evenly coated on the diffusion film 141 .

That is, as shown in FIG. 41A, the diffusion film 141 is rotated by the spin coating method to uniformly coat the first ultraviolet crosslinking agent 146 with a certain thickness on the diffusion film 141, or as shown in FIG. 41B, the diffusion film is rotated by the blade method. The film 141 is uniformly coated with the second ultraviolet crosslinking agent 147 with a certain thickness on the diffusion film 141 by the roller 55 .

Next, as shown in FIG. 42 , the cooling film 143 is disposed on the second ultraviolet crosslinking agent 147 . The first and second ultraviolet crosslinking agents 146 and 147 are irradiated with ultraviolet rays, the diffusion film 141 and the brightness enhancement film 142 are attached by the first ultraviolet crosslinking agent 146 , and the brightness enhancement film 142 and the cooling film 143 are attached by the second ultraviolet rays 147 .

like this. The diffusion film 141 , the brightness enhancement film 142 and the prism film 143 of the optical sheet part 140 of the liquid crystal display are integrally formed to prevent a concave portion between the brightness enhancement 142 and the prism film.

As described above, ultraviolet rays are irradiated to the first and second ultraviolet crosslinking agents 146 and 147 at the same time to attach the diffusion film 141 and the brightness enhancement film 142 and the prism film 143 at the same time, but the first ultraviolet crosslinking agent 146 is irradiated with ultraviolet rays to diffuse The film 141 and the brightness enhancement film are attached to each other, and then the second ultraviolet crosslinking agent 147 is applied, and then the prism film 143 is arranged thereon, and then ultraviolet rays are irradiated to the second ultraviolet crosslinking agent 147 to attach the brightness enhancement film and the prism film 143 .

In addition, as mentioned above, in order to integrally form the optical sheet part 140, the following steps were carried out in a separate facility: loading the first ultraviolet crosslinking agent 146; uniformly coating the first crosslinking agent 146; making the brightness enhancement film 142 is located on the first ultraviolet crosslinking agent 146, and the second ultraviolet crosslinking agent 147 is loaded on the brightness enhancement film 142; the second ultraviolet crosslinking agent 147 is evenly coated; the prism film 143 is positioned on the second ultraviolet crosslinking agent 147 The first and second ultraviolet crosslinking agents 146 and 147 are irradiated with ultraviolet rays, but the integrated optical sheet part can also be manufactured through a continuous process of simultaneously rolling and rocking a plurality of parts on the long drum. (IY-200401-020-1)

According to the brightness enhancement film for liquid crystal display and the manufacturing method thereof of the present invention is different from the conventional brightness enhancement film, the polymer resin layer with hexagonal lattice structure is formed on the polymer film, so as to have The reflective polarizing feature simplifies the manufacturing process of the brightness enhancement film.

Moreover, the brightness enhancement film manufacturing method for liquid crystal displays according to the present invention is different from conventional brightness enhancement films in that it is composed of optical crystal colloidal layers with a predetermined structure so that only a single layer or multiple layers have reflective polarizing properties, simplifying The manufacturing process of the brightness enhancement film is simplified, and the production cost is reduced.

Moreover, the brightness enhancement film manufacturing method for liquid crystal displays according to the present invention is different from conventional brightness enhancement films in that a polymer film containing a plurality of metal ion particles having a predetermined structure is formed so as to use only a single layer or a multilayer It has reflective polarizing characteristics, simplifies the manufacturing process of the brightness enhancement film, and reduces the production cost.

The method for manufacturing the brightness enhancement film for liquid crystal display according to the present invention is different from the traditional brightness enhancement film. It is composed of a plurality of encapsulated liquid crystal molecules oriented in a certain direction, so that only a single layer or multiple layers have reflective polarizing properties. , simplifies the manufacturing process of the brightness enhancement film, and reduces the production cost.

The brightness enhancement film manufacturing method for liquid crystal display according to the present invention is different from the traditional brightness enhancement film, forming a polymer film containing an extended core-shell structure organic particle, so as to have reflective polarizing properties with only a single layer or multiple layers, simplifying the The brightness enhancement film manufacturing process reduces the production cost.

Furthermore, the diffusion film, the brightness enhancement film, and the prism film are integrally formed so as to prevent a recess from being generated between the diffusion film, the brightness enhancement film, and the prism film whose degrees of expansion differ depending on temperature and humidity.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (18)

1. A method of manufacturing a brightness enhancement film for a liquid crystal display, said method comprising the steps of: Drop the polymer resin solution on the polymer film; uniformly distributing the polymer resin solution on the polymer film; and drying the polymer resin solution to form a polymer resin layer, Wherein the polymer resin layer has a hexagonal lattice structure. 2. The method according to claim 1, further comprising a step of thermally stretching the polymer film and the polymer resin layer in a predetermined direction. 3. The method of claim 1, wherein the polymer film comprises polycarbonate or polyethylene terephthalate material. 4. The method according to claim 1, wherein the thickness of the hexagonal lattice structure of the polymer resin layer is about 10 nm to 800 nm. 5. The method according to claim 1, characterized in that, the polymer resin solution is evenly coated on the polymer film by using a spin coating method or a blade mounting method. 6. The method according to claim 1, wherein the polymer resin layer comprises one of the following compounds or derivatives thereof: polysulfone, polymethyl methacrylate, polystyrene, polyvinyl chloride , polyvinyl alcohol, polynorbornene, polymers formed by copolymerization of the above-identified polymers. 7 . The method according to claim 2 , wherein the thermal stretching temperature of the polymer film is between the glass transition temperature of the polymer film and the glass transition temperature + 100° C. 7 . 8 . The method according to claim 2 , wherein the lengths of the polymer film and the polymer resin layer after thermal stretching are 1.1 to 8 times longer than those before thermal stretching. 9. A brightness enhancement film for a liquid crystal display, comprising: Polymer membranes; and a polymer resin layer formed on the polymer film, Wherein the polymer resin layer has a hexagonal lattice structure. 10 . The brightness enhancement film according to claim 9 , wherein the polymer film and the polymer resin layer are thermally stretched in a predetermined direction. 11 . 11. The brightness enhancement film according to claim 9, wherein the polymer film is polycarbonate or polyethylene terephthalate material. 12 . The brightness enhancement film according to claim 9 , wherein the thickness of the hexagonal lattice structure of the polymer resin layer is about 10 nm to 800 nm. 13. The brightness enhancement film according to claim 9, wherein the polymer resin layer comprises one of the following compounds or derivatives thereof: polysulfone, polymethyl methacrylate, polystyrene, poly Vinyl chloride, polyvinyl alcohol, polynorbornene, polymers formed by copolymerization of the above-identified polymers. 14. A method of manufacturing a liquid crystal display, comprising the steps of: disposing a first ultraviolet crosslinking agent on the diffusion film; uniformly coating the first ultraviolet crosslinking agent on the diffusion film; placing a brightness enhancement film on the first ultraviolet crosslinker; A second ultraviolet crosslinking agent is arranged on the brightness enhancement film; uniformly coating the second ultraviolet crosslinking agent on the brightness enhancement film; placing a prism film on the second UV crosslinker; irradiating ultraviolet rays to the first and second ultraviolet crosslinking agents, A polymer resin layer with a hexagonal lattice structure is formed on the polymer film of the brightness enhancement film. 15. The method according to claim 14, characterized in that, the first and second ultraviolet crosslinking agents are evenly coated on the diffusion film and the brightness enhancement film by using a spin coating method or a blade installation method. film. 16. A liquid crystal display comprising: The display unit can display images; a backlight unit supplying light to the display unit; and The optical sheet part is located between the display part and the backlight part, and includes a diffusion film, a prism film, and a brightness enhancement film, Wherein the brightness enhancement film includes a polymer film, and a polymer resin layer formed on the polymer film and having a hexagonal lattice structure. 17. The liquid crystal display of claim 16, wherein the brightness enhancement film is formed on the diffusion film, and the prism film is formed on the brightness enhancement film. 18. The liquid crystal display of claim 17, further comprising: attaching the diffusion film and the brightness enhancement film with a first ultraviolet crosslinking agent; and attaching the brightness enhancement film and the brightness enhancement film with a second ultraviolet crosslinking agent The prism film.

Images