TWI259292B - High-luminance light diffuser and manufacturing process thereof - Google Patents

Abstract

The present invention relates to a high-luminance light diffuser and manufacturing process thereof, which disclose alight diffuser. The light diffuser includes at least a luminance-enhancing layer located at a light-entrance side of the light diffuser, and the other light-exit side of the light diffuser can be of any form, e.g. flat surface, mirror, fog surface, focusing or diffusing lens, such that the luminance-enhancing layer converts the ultraviolet rays in a light source into visible lights to attain the luminance-enhancing object. Meanwhile, while forming light diffuser having the luminance-enhancing layer structure on a plate with co-extrusion forming technique, simultaneously consider a forming technique to coat on the surface of the diffuser to achieve the object of co-extrusion forming and the object of enhancing yield and cost down.

Description

1259292 V. INSTRUCTION DESCRIPTION (1) Technical Field of the Invention The present invention relates to a highlighting method in which a light-expanding layer of a light diffusing plate is formed on a surface of a diffusing plate. Molding technology to increase yield and reduce manufacturing costs. [Prior Art] The light diffusing plate and the manufacturing process thereof are particularly formed by using a common extrusion molding material, and are coated on the light to achieve the purpose of co-extrusion molding, in general, to increase the liquid crystal display. Brightness is achieved in the backlight module film (or prism sheet, prism, regardless of the number of lamps added or the number of lamps added or the use of brightening eet) to achieve the purpose of brightening. But bright film will increase the cost. Please refer to the first figure, which is a schematic diagram of a straight structure of the prior art; as shown in the figure, a general direct type module, a reflection sheet 10', a plurality of light sources 1 1 ', and a light diffusion sheet (prism sheet) 13', a second diffuser film 15' and the like. However, the current brightening technology on the back can be divided into four methods. First, it is a straight 稜鏡 , , , , , , , , , , 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭 搭Increase the brightness for the purpose. Second, the compensation film as a brightening technology, the principle is to use two molecular materials to form a multilayer film structure, birefringence characteristics. Vertically when the backlight passes

Ce (previously, the backlight module has a structure including a board 12' 14. The refractive index of the two water mirrors in a first light diffusing optical module is again concentrated by sawtooth and is multi-layered by different refractions and then extended by the interference film. Common flat heel and ribbed structure, high interference of reduced interference rate can produce polarized light

Page 5 8 1259292 V. Description of the invention (2) " _ ~ Direct penetration 'and the polarized light parallel to the interference film reflects the back back to the backlight module, and then re-forms the polarized light perpendicular to the interference film The method of improving the light utilization rate achieves the effect of increasing the thickness. Third, the reflection type cholesteric liquid crystal is used as a brightening technology. Fourth, directly increase the number of lamps or light sources. For backlight module manufacturers, the cost reduction method is nothing more than simplifying the module construction. Therefore, if the light energy is efficiently and uniformly dissipated from the surface of the diffuser plate, the front shell is raised. This one-piece diffuser design not only reduces the need for expensive parts (such as crepe), but also shortens the assembly time while achieving high brightness and cost reduction. φ Therefore, how to propose a novel high-brightness optical expansion plate and its process for the above problems can not only improve the conventional drawbacks that need to be assembled by assembling a light diffusing plate, a prism sheet or a brightness enhancing film to increase the brightness. No matter which technical principle is used, it is impossible to get rid of the coating production technology. However, when it comes to the production technology of surface coating, there is a problem of yield, especially when the size is larger, the yield is lower. In the present invention, a co-extrusion molding technique is specifically mentioned, and a desired brightness-increasing layer is applied to a light-incident surface of a light-diffusing sheet by a co-extrusion technique while forming a light-diffusing sheet; It is also possible to design a prismatic lens having a condensed light or a Lenticular lens having a astigmatism on the illuminating surface to achieve brightening. The brightening light diffusing plate can be directly applied to various modules of different sizes to achieve brightness enhancement, easy assembly and cost reduction. In addition, the method of brightening on the light diffusing plate has long been eagerly awaited by the user and the inventor of the present invention, and the inventor has based on years of experience in research, development, and sales of related products. Naisi 1259292 V. Invention Description (3) and the idea of improvement, poor personal expertise, after research and design, special discussion, finally developed a high-brightness light diffuser and its process improvement, can solve the above problems. SUMMARY OF THE INVENTION The main object of the present invention is to provide a high-intensity light diffusing plate and a process thereof, using a co-extrusion molding (C 〇-e X trusi ο η ) technology to directly brighten a layer containing phosphor powder At the same time, the light diffusing sheet is formed on the light incident surface of a light diffusing plate, and the thickness thereof is controlled in the range of 1 to 2 0 0 / / m. When the light source of the backlight § group includes a cold cathode tube (CCFL), a light emitting diode (LED) or a light source of a planar light source, when the brightness enhancement layer on the light diffusion plate passes, the light source is less than 400 nm ultraviolet rays. Light waves, which are generally not used, cause cracking of the material and cause yellowing. Therefore, in the present invention, the brightness enhancing layer, such as phosphor powder, is utilized to absorb ultraviolet light in the light source and convert it into visible light for the purpose of increasing brightness. [Embodiment] In order to provide the reviewing committee with a better understanding and understanding of the structural features and the effects of the present invention, the preferred embodiment and the detailed description are as follows: φ The present invention is To solve the shortcomings of the conventional direct backlight module, the conventional direct backlight module comprises a reflective sheet, a plurality of light sources, a light diffusing plate, a cymbal sheet and a brightness enhancing film, and the optical sheet is further disposed. When combined, not only increases the difficulty and time of assembly, but also has higher cost, so the present invention provides a novel light diffusing plate structure to reduce the

Page 7 1259292 V. INSTRUCTIONS (4) ' '一一一^ — The setting of the enamel and brightness enhancing film to reduce manufacturing costs and increase its brightness. > First, please refer to the second drawing, which is a preferred embodiment of the present invention, and the structure of the diffusing plate is not intended; as shown, the present invention is a structure of a light diffusing plate which increases the shell degree. The light diffusing plate 1 comprises a substrate 丨〇 and at least one fluorescent brightness enhancing layer 20 as a description of a fluorescent brightening layer. The fluorene-enhanced shell layer 2 is located on one side of the substrate. The material of the 4 substrate 10 is composed of methyl methacrylate and a styrene copolymer (MS) as a substrate of the light diffusing plate, and the substrate 1 comprises a plurality of light diffusing particles 1 2 . And the ultraviolet absorber i 3, and the other side of the light diffusing plate is the light-emitting side, which may include a flat, mirror or matte surface or a condensed or astigmatic design, as shown in the second figure. , which is a plane; as shown in Figure 2A, it is a columnar lens such as the structure of LenticuUr iens; as shown in the second B, it is a concentrating design, such as prism Uns or Fresnel lens . The phosphor powder such as 2, thiophenediylbis (5-tert-buty 1,3-benzoxazole) is applied to one side of the substrate in a co-extrusion molding manner. Furthermore, please refer to the third figure, which is a schematic structural view of a direct type backlight module according to a preferred embodiment of the present invention; as shown in the figure, the direct-sense backlight module of the present invention comprises a reflective sheet. 10 〇, a plurality of light sources 2 〇〇, a light diffusing plate 300, wherein one side of the light diffusing plate 300 includes at least one fluorescent brightening layer 3 10 and a substrate 3 2 0. The fluorescent brightening layer 3 1 is a brightening phosphor using 2, 5-thiophenediylbis ( 5-tert-buty 1 - 1? 3-be η zoxazo 1 e ), which is a co-extrusion molding technique. labor

Page 8 1259292+ V. Description of the invention (5) The light-increasing layer is disposed on the light-incident surface of the light-diffusing plate 300, when the plurality of light sources 200 of the backlight module pass through the light-diffusing plate When the fluorescent brightening layer is 3 〇〇, the ultraviolet light wave (especially the wavelength of 3 75 nm) of less than 400 nm in the light source is irradiated to the fluorescent powder to generate visible light, thereby increasing the brightness. In general, the phosphor powder may be dispersed in a solvent or a polymer solution, and the phosphor powder may be coated on the surface of the diffusing plate by a coating technique to form a fluorescent brightening layer. There are many coating technologies that can be used in production, such as ceramic coating, spin coating, roller coating, spray coating, and stencil printing. Screen printing), Die coating and Scrap coating. The desired phosphor powder can be applied to the surface of the diffuser. The above coating techniques include solvent drying and dry hardening (C uring ) granulation such as heat hardening or photo hardening, etc. The uniformity problem of the cloth and the yield problem have more complicated labor and waste of energy. In the present invention, it is proposed to use a co-extrusion molding technique to apply a desired fluorescent brightening layer to a surface of a sheet to form a fluorescent brightening layer on the surface as a light-emitting surface of the light-diffusing sheet. Cooling through the roller or at the same time a special optical structure can also be reproduced to shape the light exit surface of the light diffusing plate, such as a prism lens with concentrating or a lenticular lens with astigmatism (Lenticu 1 ar 1 ens ) . The co-extrusion molding technology uses two or more extruders to distinguish between Ma in extruder and Sub-extruder. Among them, the secondary extrusion machine can be one or more according to the demand. If one is capable of producing a two-layer or three-layer structure, as shown in Fig. 4, a light diffusing plate has a three-layer structure. Main extrusion machine (M a i η 8

1259292 5, invention description (6) ~ extruder), mainly to provide the middle layer is the light diffusion layer. Polycarbonate (PC), polymethyl methacrylate (PMMA), methyl methacrylate styrene copolymer (MS), cyclic olefin copolymer (COC), polyethylene terephthalate are generally used. A transparent grade plastic material of one of a group of materials such as diester (PETG) or polystyrene (ps), and various diffusion particles having a diffusion function are added. The secondary extrusion machine (S ub - e X truder ) mainly provides a surface coating layer. In the present invention, a fluorescent brightening layer is mainly provided, and the main raw material is also polycarbonate (p C ), polymethyl methacrylate. (ρ μ Μ A ), methyl methacrylate and styrene copolymer (MS), cyclic olefin copolymer (jCOC), polyethylene terephthalate (PETG) or polystyrene (ps) a transparent grade of plastic material of any one of the group, plus a phosphor powder for brightening purposes, or a second stage extruder providing an ultraviolet absorbing layer may be present in the fluorescent buildup layer and the light diffusing interlayer Alternatively, or directly adding an ultraviolet absorber to the middle of the light diffusion to form an ultraviolet absorbing layer 3, as shown in the fifth figure. 6 is a flow chart for manufacturing a light diffusing plate according to a preferred embodiment of the present invention; a method for manufacturing a light diffusing plate having a fluorescent reinforcing layer according to the present invention, and main manufacturing steps thereof The method includes the following steps: Step S1 0 'Using a main outlet to extrude a substrate of a plurality of light-diffusing particles and an ultraviolet absorber to form a substrate of a light-diffusing plate; and calling the step S2〇' to use a sub-extruder The phosphor added with a phosphor powder is extruded to form a fluorescent brightness enhancing layer; in step S30, the fluorescent brightness enhancing layer is coated on the light diffusion layer by a multi-layered τ-type die (T-die) At least one surface of the layer; and step S40' coextruding the light diffusion layer and the fluorescent brightness enhancing layer into a plate shape

Page 10 8 1259292____ f V. INSTRUCTIONS (7) Structured high-intensity light diffuser. An embodiment will now be described. Produce a diffusion plate of M m material of 2 m m, add 1 〇 % Ρ Μ Μ A light-diffusing particles, and add 3% of the absorbent with UV-absorbing light source. Both sides are matte surfaces, in which the light-incident surface is coated with 2% of 2,5-thiophenediylbis (5-tert-butyl-1,3-benzoxazole) as a fluorescent brightening layer. The thickness is controlled to a thickness of 50/zm as a function of converting ultraviolet rays into visible light. Finally, please refer to the seventh drawing, which is a block diagram of the manufacturing of the high-intensity light diffusing plate according to a preferred embodiment of the present invention; and the high-intensity light diffusing plate of the present invention and the manufacturing method thereof The main system uses a main extruder 400 to add a 1%% PMM A light-diffusing fine particle and 3% of the ultraviolet absorber 2000 MS resin 300 to form a light diffusion layer 500. Using a single extruder (S ub - e X truder ) 800 , the 50# m MS layer 70 0 of 2% phosphor powder 600 is extruded to form a fluorescent brightening layer 9〇〇, by a multilayer T-die (T-die) 9 5 0, the fluorescent brightening layer 9 is contacted with the surface of the diffusing plate 500; the MS light diffusing layer 500 and at least one fluorescent brightening layer 9 0 0 A high-intensity light diffusing plate 9 8 共同 that is co-extruded into a plate-like structure. In summary, the present invention is a novelty, progressive and available for industrial users to 'accord to the patent application requirements of the Chinese Patent Law. Granting a patent, it is a prayer. However, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and the shapes, structures, features, and spirits described in the scope of the patent application are equally changed. repair

Page 11 1259292 V. INSTRUCTIONS (8) Decorations are to be included in the scope of the patent application of the present invention.

Page 12 1259292 Schematic description of the structure of the group of light-backed straight-down techniques. The description of the method is a simple example of the singularity of the illuminating plate. The real picture is better than the one shown in the structure.萤 图 图 图 图 图 图 图 图

Figure A

The B-shaped light column is scattered with a plate. Plate expansion and expansion Tfe shows * Example 4 Φ example fe έ ν fe real layer good "p good" Qi j is more than 35 > light one > 夂 夂 及 π and # YMJ, y » MJ. The system is 组S its group mode light back type. The following example shows the structure of the straightforward structure. The layer is brighter and brighter. The light is made by Firefly and it is thought that the system has a layered layer with a plate with diffused light. Compared with the figure shown in Fig. 1, it is better to use the case where the glazed fluorescing light has a plate diffused light. Figure Creativity Diagrams Figure 5 Figure VII Figure VII Diffusion luminosity 〇 图 高 高 高 高 高 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例 示例The example of the brightening of the plate and the brightness of the plate is better than that of the one. The figure of the process is made by the block of the system. [Main component symbol description] 1 〇 'reflection film 1 1 ' Multiple light sources 1 2 'light diffuser

Page 13(S) 1259292 Schematic description 1 3 'First cymbal 1 4 'Second cymbal 1 5 'Light diffusing film 10 Light diffusing plate 12 Light diffusing particles 13 Ultraviolet absorbing agent 20 Fluorescent brightening layer 1 0 0 Reflector 2 0 0 Light source UV absorbing layer ▼0 0 Light diffusing plate 3 1 0 Fluorescent brightening layer 3 2 0 Light diffusing layer 2 0 0 Light diffusing particles and UV absorber 3 0 0 MS resin 4 0 0 main Extruder 500 light diffusing layer 6 0 0 fluorescent powder 7 0 0 MS resin _ 0 extrusion machine 9 0 0 fluorescent brightening layer 9 5 0 multilayer 模 type die 9 8 0 high brightness light diffusing plate

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Claims (1)

1259292 I. Patent application scope 1. A high-intensity light diffusing plate, the main structure of which comprises: a substrate; and at least one brightness enhancing layer, which is located on one side of the substrate, and the brightness enhancing layer contains a firefly The light powder can convert the invisible portion passing through the light diffusing plate into a visible light wavelength. 2. The structure of claim 1, wherein the substrate is selected from the group consisting of polycarbonate (PC), polymethyl methacrylate (PMMA), methyl methacrylate, and styrene copolymerization. One of a group consisting of (MS), cyclic olefin copolymer (COC), polyethylene terephthalate (PETG), or polystyrene (PS). The structure of claim 1, wherein the brightness enhancing layer comprises a fluorescent powder such as 2,5-thiophenediylbis (5-tert-butyl-1,3-benzoxazole) having a light The function of converting invisible light with a wavelength below 400 nm into visible light. 4. The structure of claim 1, wherein one side of the substrate is the brightness enhancing layer and the other side is in any shape. 5. The structure of claim 4, wherein any shape of the other side of the substrate can be a flat or mirror or matte surface. 6. The structure of claim 4, wherein the outer side of the substrate is arbitrarily shaped like a prism lens or a frusnel lens or a lenticular lens having astigmatism ( Lenticular 1 ens ) structure. 7. The structure of claim 6, wherein any shape of the other side of the substrate may be a 稜鏡 (P r i s m ). 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 9. The structure of claim 1, wherein the light diffusing plate is used as a light diffusing plate for a backlight module of a liquid crystal display. The structure of claim 9, wherein the light source of the backlight module comprises a cold cathode tube (CCFL), a light emitting diode (LED) or a light source of various planar light sources. 1 1. A high-intensity light diffusing plate process, the main manufacturing steps comprising: using a main outlet to extrude a substrate of a plurality of light-diffusing particles and an ultraviolet absorbing agent to form a substrate of a light diffusing plate; The squeezing machine (S ub - e X truder ) extrudes a resin added with a phosphor powder to form a brightness enhancing layer; the brightness enhancing layer is coated on the light by a multi-layer T-die (T - die ) At least one surface of the diffusion layer; and a light diffusion plate that is coextruded with the light diffusion layer and the brightness enhancement layer into a plate-like structure. Page 16