CN101441285A - A reflective sheet - Google Patents

Abstract

The reflecting sheet mainly comprises a base material, a metal layer, a multilayer reflector and a diffusion layer, wherein the multilayer reflector is provided with more than two reflecting layers with different refractive indexes, the multilayer reflector is arranged on the upper surface of the metal layer, or the base material can be arranged between the multilayer reflector and the metal layer, the diffusion layer can be arranged on the lower surface of the base material or the metal layer, the metal layer and the multilayer reflector can have better reflectivity (up to 95-98%) in a wide wavelength range (about 380-780 nm), and the diffusion layer can be used for simultaneously enabling the passing light to achieve the effect of light diffusion.

Description

A reflective sheet

technical field

The present invention relates to a manufacturing method of a reflector, a reflector and its application. The purpose is to provide better reflectivity, so that when it is applied to a lamp reflector, a reflector under a light guide plate, a backlight device and a liquid crystal display device, a higher reflectivity can be obtained. High brightness reflector.

Background technique

Press, the liquid crystal display that is generally used in the information device can choose to use the direct type or the side-light backlight device structure according to the actual design requirements; as shown in Figure 1A, it is the basic structure of the side-light backlight device Schematic diagram of the structure, which mainly installs a light source 12 in a carrier 11, and sets the end of a light guide plate 13 on the opening of the carrier 11, and above the light guide plate 13, several optical films 14 and liquid crystals are arranged in sequence Panel 15, so that the light from the light source 12 enters the light guide plate 13 from the plate end and exits toward the expected plate surface of the light guide plate 13, so as to achieve the effect displayed by the liquid crystal panel 15; wherein, each optical film 14 generally utilizes a lower diffusion sheet 141, The light enhancing sheet 142 and the upper diffusing sheet 143 are disposed above the light guide plate 13 in sequence, so that each optical film 14 can increase the diffusion effect of the light source to achieve a uniform light effect.

In addition, a reflective sheet 16 is provided below the light guide plate 13. Under the action of the reflective sheet 16, the light from the light source 12 can be emitted toward the light source exit surface as much as possible, so as to increase the brightness performance of the light source exit surface; however, the single reflective sheet 16 Reflection, although part of the light can be emitted toward the direction of the light emitting surface, but a small part of the light will be missed, and the most effective use of the light source cannot be achieved.

Therefore, there are such as China Taiwan Patent Announcement No. CN1791810 and No. CN1745317, which all include a metal layer 17, a high refractive index layer 18 and a low refractive index layer 19, as shown in Figure 1B, and from top to bottom The sequence is a high refractive index layer 18, a low refractive index layer 19 and a metal layer 17 to form a reflector with a higher reflectivity, and when the reflector is used in a backlight device, the light emitted by its light-emitting surface is not large. Uniform light, such as light with residual lamp shadows, will produce brightness differences on the screen of the liquid crystal display device, deteriorating the picture quality. Therefore, such lighting devices are required to have good light emission quality with uniform luminance distribution over the entire light emitting surface.

Therefore, in order to achieve the luminous quality with uniform overall luminance distribution, a corrugated or mountain-shaped structure will be further formed on the reflector to diffuse the light; however, in the case of using the above-mentioned reflector, the reflector’s The shape is complex, and it is difficult to set an optimal shape for improving the light emission quality. There is also a problem that the reflector needs to be processed, and the positional relationship between the light source and the shape of the reflector needs to be set with high precision.

Contents of the invention

The main purpose of the present invention is to provide a reflective sheet, a manufacturing method of a reflector and applications thereof. The purpose is to provide a reflective sheet with a better reflectivity, so that it can be applied to lamp reflectors, backlight devices and liquid crystal display devices. Obtain a reflective sheet with higher brightness.

To achieve the above disclosure purpose, the reflective sheet of the present invention mainly includes a base material, a metal layer, a multilayer reflector and a diffusion layer, and the multilayer reflector is provided with more than two reflective layers with different refractive indices, wherein the multilayer The multi-layer reflector is arranged on the upper surface of the metal layer, or a substrate can be arranged between the multilayer reflector and the metal layer, and the diffusion layer can be arranged on the lower surface of the substrate or the metal layer, through the metal layer and the multilayer reflection The body can have a better reflectivity (up to 95-98%) in a wide wavelength range (about 380-780nm), and the diffusion layer can be used to achieve the effect of light diffusion at the same time.

Description of drawings

FIG. 1 is a schematic structural diagram of a conventional edge-lit backlight module;

Fig. 2 is a schematic structural view of the reflecting sheet of the first embodiment of the present invention;

Fig. 3 is a schematic flow chart of the manufacturing steps of the reflective sheet in the first embodiment of the present invention;

Fig. 4 is a schematic structural view of the second embodiment of the reflection sheet in the present invention;

Fig. 5 is a schematic flow chart of the manufacturing steps of the reflective sheet in the second embodiment of the present invention;

FIG. 6 is a schematic structural view of a reflection sheet according to a third embodiment of the present invention;

7 is a schematic flow chart of the manufacturing steps of the reflective sheet in the third embodiment of the present invention;

8A and B are structural schematic diagrams of reflective sheets of the fourth and fifth embodiments of the present invention;

9A, B, and C are structural schematic diagrams of reflectors in the sixth, seventh, and eighth embodiments of the present invention;

10A and B are structural schematic diagrams of reflective sheets applied to lamp reflectors in the present invention;

11A and B are structural schematic diagrams of reflective sheets applied to edge-lit backlight devices in the present invention;

FIGS. 12A and 12B are structural schematic diagrams of the reflective sheet applied to the direct-lit backlight device of the present invention.

【Description of figure number】

Vehicle 11 Light source 12 Light guide plate 13

Optical film 14 Lower diffusion sheet 141 Brightening sheet 142

Upper diffuser 143 LCD panel 15 Reflector 16

Metal layer 17 High refractive index layer 18 Low refractive index layer 19

Reflector 2 Substrate 21 Metal layer 22

Multi-layer reflector 23 First reflective layer 231 Second reflective layer 232

The third reflection layer 233 Nth reflection layer N diffusion layer 24

Polymer resin 241 Diffusion particles 242 Hard coating 25

Light-transmitting particles 251 Protective layer 26 Adhesive layer 27

Metal substrate 28 Lamp reflector 3 Light source 31

Vehicle 41 Light source device 42 Light guide plate 43

Diffusion plate 44

Detailed ways

The features of the present invention can be clearly understood by referring to the drawings and the detailed description of the embodiments.

The reflection sheet of the present invention, the structure of the reflection sheet 2 as shown in Figure 2, at least includes:

A base material 21, the base material 21 can be a transparent resin material.

A metal layer 22, the metal layer 22 is arranged on one side surface of the substrate 21, in the embodiment shown in the figure, the metal layer 22 is arranged on the upper surface of the substrate 21, the metal layer 22 can be aluminum or Silver and other metal materials.

A multilayer reflector 23, the multilayer reflector 23 is arranged on the other side surface of the metal layer 22 relative to the substrate 21, the multilayer reflector 23 can be arranged on the upper surface of the metal layer 22, the multilayer reflector 23 There are more than two reflective layers with different refractive indices, and the multilayer reflector 23 includes a first reflective layer 231, a second reflective layer 232, a third reflective layer 233 to an Nth reflective layer in order from above the metal layer 22. N, where N is less than or equal to 50, the refractive index of the first reflective layer 231 is smaller than that of the second reflective layer 232, and the difference in refractive index between the upper and lower adjacent reflective layers is greater than 0.4, that is, the first and second reflection The refractive index differences between the layers 231 and 232 and between the second and third reflective layers 233 and 233 are both larger than 0.4, and the refractive index of the third reflective layer 233 may be smaller or larger than that of the second reflective layer 232 .

A diffusion layer 24, the diffusion layer 24 is arranged on the other side surface of the substrate 21 relative to the metal layer 22, in this embodiment, the diffusion layer 24 is arranged on the lower surface of the substrate 21, the diffusion layer 24 contains high Molecular resin 241 and a plurality of diffusion particles 242, the diffusion particles 242 may be white substances such as titanium dioxide, barium sulfate, calcium carbonate or a mixture thereof; of course, the diffusion layer may also be white or opaque polymer resin.

Furthermore, the manufacturing method of the reflection sheet in the above-mentioned embodiment, as shown in FIG. 3 , includes the following steps:

A. Provide a substrate, which can be a transparent resin material, such as polyethylene terephthalate (PET), cellulose triacetate (TAC), polyethylene naphthalate (PEN), Polypropylene diester, polyimide, polyether, polycarbonate, polyamine, polyethylene, polypropylene or polyvinyl alcohol, polystyrene, polymethyl methacrylate, polyvinyl chloride, epoxy resin, phenolic resin etc. or its equivalent.

B. On one side of the substrate, a metal layer is formed by a physical vapor deposition process, and the physical vapor deposition process can be sputtering or evaporation technology, and the metal layer can be made of metal elements or metal derivatives or metal oxides Composition, for example, may be aluminum or silver.

C. On the surface of the metal layer opposite to the substrate, a multi-layer reflector is formed by physical vapor deposition process or coating method.

D. Form a diffusion layer on the surface of the base material opposite to the metal layer by means of coating (may be wet coating) to complete the reflective sheet 2 structure as shown in the first embodiment in FIG. 2 .

In the second embodiment shown in FIG. 4 , the reflection sheet 2 also includes: a substrate 21, a metal layer 22, a multilayer reflector 23 and a diffusion layer 24, and the diffusion layer 24 is arranged on one side of the substrate 21 surface (can be the upper surface), the metal layer 22 is arranged on the other side surface (can be the upper surface) of the diffusion layer 24 relative to the substrate 21, and the multilayer reflector 23 is arranged on the metal layer 22 relative to the diffusion layer 24 on the other side surface (can be the upper surface), so that the reflection sheet 2 is sequentially from top to bottom: multilayer reflector 23, metal layer 22, diffusion layer 24 and substrate 21, and the multilayer reflector 23 The first reflective layer 231, the second reflective layer 232, the third reflective layer 233 to the Nth reflective layer N are also sequentially included above the metal layer 22, wherein N is less than or equal to 50, and the refractive index of the first reflective layer 231 is smaller than the second reflective layer 232, and the refractive index difference between the upper and lower adjacent reflective layers is greater than 0.4.

Furthermore, the manufacturing method of the reflecting sheet in the second embodiment above, as shown in FIG. 5 , includes the following steps:

A. Provide a substrate, which can be a transparent resin material, such as polyethylene terephthalate (PET), cellulose triacetate (TAC), polyethylene naphthalate (PEN), Polypropylene diester, polyimide, polyether, polycarbonate, polyamine, polyethylene, polypropylene or polyvinyl alcohol, polystyrene, polymethyl methacrylate, polyvinyl chloride, epoxy resin, phenolic resin etc. or its equivalent.

B. On the surface of one side of the substrate, a diffusion layer is formed by coating.

C. On the other side surface of the diffusion layer relative to the substrate, a metal layer is formed by a physical vapor deposition process, and the physical vapor deposition process can be sputtering or evaporation technology, and the metal layer can be made of metal elements or metal derivatives Or composed of metal oxides, such as aluminum or silver.

D. On the surface of the metal layer on the other side of the diffusion layer, use a physical vapor deposition process or coating method to form a multi-layer reflector, and the physical vapor deposition process can be sputtering or evaporation technology to complete as shown in the figure The reflective sheet 2 structure shown in the second embodiment in 4.

In the third embodiment shown in Figure 6, the reflection sheet 2 also includes: a base material 21, a metal layer 22, a multi-layer reflector 23 and a diffusion layer 24, and the metal layer 22 is arranged on one side of the base material 21. Side surface (can be the lower surface), the multilayer reflector 23 is arranged on the other side surface (can be the upper surface) of the substrate 21 relative to the metal layer 22, and the diffusion layer 24 is arranged on the metal layer 22 relative to the substrate 21 The other side surface (can be the lower surface), so that the reflective sheet 2 from top to bottom is: multilayer reflector 23, base material 21, metal layer 22 and diffusion layer 24, and the multilayer reflector 23 consists of The substrate 21 also includes a first reflective layer 231, a second reflective layer 232, a third reflective layer 233 to an Nth reflective layer N in sequence, wherein N is less than or equal to 50, and the refractive index of the first reflective layer 231 is less than For the second reflective layer 232, the difference in refractive index between the upper and lower adjacent reflective layers is greater than 0.4.

Furthermore, the manufacturing method of the reflection sheet in the third embodiment above, as shown in FIG. 7 , includes the following steps:

A. Provide a substrate, which can be a transparent resin material, such as polyethylene terephthalate (PET), cellulose triacetate (TAC), polyethylene naphthalate (PEN), Polypropylene diester, polyimide, polyether, polycarbonate, polyamine, polyethylene, polypropylene or polyvinyl alcohol, polystyrene, polymethyl methacrylate, polyvinyl chloride, epoxy resin, phenolic resin etc. or its equivalent.

B. On one side of the substrate, a metal layer is formed by a physical vapor deposition process, and the physical vapor deposition process can be sputtering or evaporation technology, and the metal layer can be made of metal elements or metal derivatives or metal oxides Composition, for example, may be aluminum or silver.

C. On the surface of the substrate opposite to the metal layer, a multi-layer reflector is formed by physical vapor deposition process or coating method, and the physical vapor deposition process can be sputtering or evaporation technology.

D. Form a diffusion layer on the surface of the metal layer opposite to the base material by means of coating, so as to complete the reflective sheet 2 structure as shown in the third embodiment in FIG. 6 .

And the upper surface of the multilayer reflector 23 of the reflective sheet of the above-mentioned embodiments is further provided with a hard coating 25, as shown in the fourth embodiment of FIG. 8A, a plurality of light-transmitting particles 251 ( particle), so that the hard coating 25 can not only protect the multi-layer reflector 23 below, but also use a plurality of light-transmitting particles 251 to have a diffusion function, and the upper surface of the hard coating 25 can be further protected Layer 26, as shown in the fifth embodiment of FIG. 8B, the protective layer 26 is detachably disposed on the hard coating 25, for example, it can be disposed on the hard coating by using a release method, so that the reflective sheet is bent. When being folded into different shapes, the protective layer 26 can be used to prevent deformation of the reflective sheet due to stress, and the protective layer can be torn off after the integral reflective sheet is formed.

In addition, a metal substrate can be further provided on the bottom layer of the reflective sheets of the above-mentioned embodiments to form a reflector structure, as shown in the sixth embodiment of FIG. 9A , the reflective sheet 2 is as follows from top to bottom: Multi-layer reflector 23, metal layer 22, substrate 21 and diffusion layer 24, the lower surface of the diffusion layer 24 can be combined with the metal substrate 28 through the adhesive layer 27, or as shown in the seventh embodiment of Figure 9B, the reflector Sheet 2 is sequentially from top to bottom: a multilayer reflector 23, a metal layer 22, a diffusion layer 24, and a substrate 21. The lower surface of the substrate 21 can be bonded to a metal substrate 28 through an adhesive layer 27, and the multilayer The upper surface of the reflector 23 can also be provided with a hard coating 25, or as shown in the eighth embodiment of FIG. Layer 22 and diffusion layer 24, the lower surface of the diffusion layer 24 can be bonded to the metal substrate 28 through the adhesive layer 27, wherein in the above-mentioned embodiments, the bottom layer (substrate or diffusion layer) of the reflection sheet and the metal substrate The bonding stress is greater than 0.1kN/m ² .

The overall reflection sheet is provided with a metal layer and a multi-layer reflector, and the multi-layer reflector is provided with more than two layers (up to 50 layers) of reflective layers with different refractive indices, so that the light can be refracted multiple times when the light passes through. Reflection, and compared with the two patents mentioned in the above-mentioned prior art, this patent only has two reflective layers with different refractive indices, and the range of increase in reflectivity is limited, while the present invention utilizes more than two layers (up to 50 layers) The role of multi-layer reflective layers stacking each other not only makes the light have better reflectivity (up to 95-98%) in a wide wavelength range (about 380-780nm), but also makes it easy to reflect The light forms a Brewster's angle, which can increase the light source of polarization to increase the luminance of the light, and can further use the light-transmitting particles in the diffusion layer or hard coating to further reflect the light , and at the same time make the passing light achieve the effect of light diffusion.

In addition, the reflective sheet of the present invention can be applied to liquid crystal display devices, and is suitable for surface light source devices (also called backlight devices) of liquid crystal televisions and side-light type surface light source devices for notebook computers. the best. More specifically, it can be used as a lamp reflector or a light guide plate lower reflector. FIG. 10A shows an embodiment of a lamp reflector to which the reflective sheet of the present invention is applied. The lamp reflector 3 is shaped to cover a light source 31 such as a fluorescent lamp with a sheet-shaped reflecting sheet 2 of the present invention. Of course, the reflecting sheet 2 may be formed in an arc shape as shown in the figure, or may be ㄈ Shape, as shown in Figure 10B, or processed into other desired appearance.

The reflection sheet of the present invention can also be installed in a direct-type or side-light backlight device, as shown in FIG. A light source device 42 and a plurality of optical films are mainly arranged in a carrier 41. The plurality of optical films can be at least composed of a reflective sheet 2 and a light guide plate 43, and the plate end of the light guide plate 43 is sleeved on the carrier 41. At the opening, the light source device 42 is also arranged on the side of the carrier 41, and the reflective sheet 2 is arranged under the light guide plate 43, so that the light from the light source device 42 enters the light guide plate 43 from the end of the plate and is directed toward the expected plate of the light guide plate 43. to achieve the effect of light source display; of course, the light guide plate can also be arranged above the light source device, and the reflective sheet can be arranged between the carrier and the light source device to form a direct-type backlight module; and the reflective sheet 2 can also be One body is bent into the shape of the carrier, as shown in FIG. 11B .

As shown in FIG. 12A, it is a schematic diagram of the basic structure of the reflective sheet of the present invention installed in a direct-type backlight device. It mainly arranges a light source device 42 and an optical film above a carrier 41. The optical film can be formed by the reflective sheet 2. and a diffuser plate 44, and the diffuser plate 44 is arranged above the light source device 42, and its reflection sheet 2 is arranged between the carrier 41 and the light source device 42, so that the light from the light source device 42 enters the diffuser plate 44 and goes toward The expected surface of the diffusion plate 44 projects out to achieve the effect of light source display; and the reflective sheet 2 can also be integrally bent into the shape of the carrier, as shown in FIG. 12B .

In addition, it can also be applied to lamp reflectors of direct display devices such as LED backlights, projection TVs, front lights, and PDAs and mobile phones. Moreover, since the reflectance is high, it can be utilized as a light collector material of a solar cell. In addition, it can also be used in strobes, signal displays, car lights, fluorescent lights, flashlights, and reflectors for art lighting that require high-grade light weight and impact resistance, as well as curved mirrors and lighting. rear mirror.

The technical content and technical characteristics of the present invention have been disclosed above, but those skilled in the art may still make various replacements and modifications based on the disclosure of the present invention without departing from the spirit of the present invention. Therefore, the protection scope of the present invention should not be limited to those disclosed in the embodiments, but should include various replacements and modifications that do not depart from the present invention, and are covered by the scope of the following patent applications.

Claims (13)

1. A reflective sheet, the reflective sheet at least includes: A substrate, the substrate is a transparent resin material; a metal layer; A multi-layer reflector, the multi-layer reflector sequentially includes from above the metal layer: the first reflective layer, the second reflective layer to the Nth reflective layer, wherein N is less than or equal to 50, and the refraction of the first reflective layer The refractive index is lower than that of the second reflective layer, and the difference in refractive index between the upper and lower adjacent reflective layers is greater than 0.4; a diffusion layer. 2. The reflection sheet according to claim 1, wherein the metal layer is disposed on the upper surface of the substrate, the multi-layer reflector is disposed on the upper surface of the metal layer, and the diffusion layer is disposed on the lower surface of the substrate. 3. The reflection sheet according to claim 1, wherein the multi-layer reflector is disposed on the upper surface of the substrate, the metal layer is disposed on the lower surface of the substrate, and the diffusion layer is disposed on the lower surface of the metal layer . 4. The reflection sheet according to claim 1, wherein the diffusion layer is disposed on the upper surface of the substrate, the metal layer is disposed on the upper surface of the diffusion layer, and the multilayer reflector is disposed on the upper surface of the metal layer . 5. The reflection sheet according to claim 2, 3 or 4, wherein a metal substrate is further combined under the reflection sheet. 6. The reflective sheet according to claim 5, wherein an adhesive layer is further provided between the reflective sheet and the metal substrate. 7. The reflection sheet according to claim 5, wherein the upper surface of the multi-layer reflector is further provided with a hard coating. 8. The reflective sheet as claimed in claim 7, wherein a plurality of light-transmitting particles are disposed in the hard coat layer. 9. The reflective sheet according to claim 5, wherein the bonding stress between the reflective sheet and the metal substrate is greater than 0.1kN/m ² . 10. The reflection sheet as claimed in claim 1, 2, 3 or 4, wherein the diffusion layer comprises polymer resin and diffusion particles, or may be white or opaque polymer resin. 11. The reflective sheet as claimed in claim 10, wherein the diffusing particles are white substances of titanium dioxide, barium sulfate, calcium carbonate or a mixture thereof. 12. The reflective sheet as claimed in claim 1, 2, 3 or 4, wherein the metal layer or multi-layer reflector can be formed by physical vapor deposition process, wherein the physical vapor deposition process can be sputtering or evaporation technology. 13. The reflective sheet according to claim 1, 2, 3 or 4, wherein the multi-layer reflector or diffusion layer can be formed by coating.

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