201018575 九、發明說明： . 【發明所屬之技術領域】 . 本發明涉及一種製造導光板之方法，尤其涉及一種注 射成型製造薄形導光板之方法。 【先前技術】 目前較為成熟之製造導光板之技術係採用注射成型 (Injection Molding)機’將導光板材料熔融後推進注射成型 機之模腔内，保持模腔之壓力並冷卻導光板材料，然後將 ❹成型之產品取出。 惟，傳統之注射成型機之注射速度和注射壓力較低， 成型之導光板厚度較厚，使得採用該導光板之背光模組體 積大、質量較大，不適應產品輕、薄之需要。 【發明内容】 有鑒於此，有必要提供一種注射成型製造薄形導光板 之方法。 一種注射成型製造導光板之方法，包括：於4000至 ❿4500千牛之鎖模力、2〇〇〇至4〇〇〇千克力/平方釐米之注射 壓力以及600至1〇〇〇毫米/秒之注射速度下注射成型導光 板。 本實施例於高注射壓力和注射速度注射成型導光板， 高注射速度和壓力可提高產品之尺寸精度，並可製造出厚 度薄之產品；該方法不僅可製造較薄之導光板，也可節約 材料’降低採用導光板之背光模組之體積。 【實施方式】 5 201018575 下面結合附圖對本發明實施例作詳細描述。 • 如圖1所示，本發明實施例注射成型製造導光板之方 . 法主要包括以下步驟： 將動模與定模合模，形成模腔，動模和定模之間具有 4000至4500千牛之鎖模力； 以6000至1000毫米/秒之注射速度以及2000至4000 千克力/平方釐米之注射壓力向模腔内注射材料； 保持模腔之壓力； ❹ 冷卻； 開模，取出產品。 如圖2所示，注射成型製造導光板之注射設備包括動 模10和定模20。工作過程中，定模20相對固定，而動模 10相對定模20運動。 如圖3所示，動模10於驅動裝置之驅動下靠近定模 20，使得動模10和定模20之間形成一個模腔30。 本實施例中，採用伺服馬達驅動之雙曲軸式之合模裝 〇 置將動模10和定模20合模，該合模裝置可產生高達4000 至4500千牛（kN)之鎖模力，該伺服馬達之功率為30至35 千瓦。高鎖模力可保證於注射成型時，動模10和定模20 之間不會發生溢料之現象。 曲軸之機械效能係數為35。 如圖4所示，螺桿40以600至1000毫米/秒（mm/s)之 注射速度以及2000至4000千克力/平方釐米（kgf/cm2)之注 射壓力將熔融之材料50注射入模腔30中。 6 201018575 注射壓力優選3000至4000千克力/平方釐米，注射速 *度優選80〇至1000毫米/秒。 • 材料50為聚甲基丙婦酸甲酯（PMMA)、聚碳酸酯（pc) 或共聚環狀埽烴（C〇C)。 如圖5所示’保持模腔3〇内之壓力並冷卻一段時間 後，於合模裝置之帶動下，動模1〇和定模2〇分開，然後 將導光板60取出。 上述工藝可製造厚度為〇·4至0.8毫米（mm)之導光板， ©尤其係厚度為0.4至〇6毫米之導光板。 以PC為例，當注射壓力為4000千克力/平方釐米時， 導光板60之厚度可達015至〇 6毫米。 ^ 提高注射壓力可成型薄形之產片，提高注射速度可成 型形狀複雜及厚度薄之產品，並有利於產品之穩定和提高 尺寸精度。 另外’由於採用高注射壓力和注射速度可製造出厚度 較薄之產品，從而可節約材料，減少使用導光板之產品之 體積6 综上所述’本發明確已符合發明專利之要件，遂依法 提出專利申请。惟，以上所述者僅為本發明之較佳實施方 式，自不能以此限制本案之申請專利範圍。舉凡熟悉本案 技藝之人士援依本發明之精神所作之等效修飾或變化，皆 應涵蓋於以下申請專利範圍内。 【圖式簡單說明】 圖1係本發明實施例注射成型製造導光板之方法之流 201018575 程圖。 . 圖2係本發明實施例注射成型製造導光板過程中提供 . 之注射成型機之示意圖。 圖3係本發明實施例注射成型製造導光板過程中之合 模不意圖。 圖4係本發明實施例注射成型製造導光板過程中之注 射材料之不意圖。 圖5係本發明實施例注射成型製造導光板過程中之取 ❹出導光板之示意圖。 【主要元件符號說明】 動模 10 定模 20 模腔 30 螺桿 40 材料 50 導光板 60201018575 IX. Description of the Invention: [Technical Field of the Invention] The present invention relates to a method of manufacturing a light guide plate, and more particularly to a method of producing a thin light guide plate by injection molding. [Prior Art] At present, the more mature technology for manufacturing light guide plates uses an injection molding machine to melt the light guide plate material and then push it into the cavity of the injection molding machine, maintain the pressure of the cavity and cool the material of the light guide plate, and then Take out the molded product. However, the injection speed and injection pressure of the conventional injection molding machine are relatively low, and the thickness of the formed light guide plate is thick, so that the backlight module using the light guide plate has a large volume and a large mass, and is not suitable for the light and thin products. SUMMARY OF THE INVENTION In view of the above, it is necessary to provide a method of injection molding a thin light guide plate. A method for producing a light guide plate by injection molding, comprising: a clamping force of 4,000 to 5004,500 kN, an injection pressure of 2 to 4 kg/cm, and 600 to 1 mm/sec. The light guide plate is injection molded at an injection speed. In this embodiment, the light guide plate is injection molded at a high injection pressure and an injection speed, and the high injection speed and pressure can improve the dimensional accuracy of the product, and can manufacture a thin product; the method can not only manufacture a thin light guide plate, but also saves The material 'reduced the volume of the backlight module using the light guide plate. [Embodiment] 5 201018575 Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. As shown in Fig. 1, the embodiment of the present invention is an injection molding method for manufacturing a light guide plate. The method mainly comprises the following steps: clamping a movable mold and a fixed mold to form a cavity, and having 4000 to 4500 k between the movable mold and the fixed mold The clamping force of the cow; injecting the material into the cavity at an injection speed of 6000 to 1000 mm/sec and an injection pressure of 2000 to 4000 kgf/cm; maintaining the pressure of the cavity; 冷却 cooling; opening the mold and taking out the product. As shown in Fig. 2, an injection apparatus for injection molding a light guide plate includes a movable mold 10 and a stationary mold 20. During operation, the fixed mold 20 is relatively fixed, and the movable mold 10 is moved relative to the fixed mold 20. As shown in Fig. 3, the movable mold 10 is driven by the driving means to approach the fixed mold 20, so that a cavity 30 is formed between the movable mold 10 and the fixed mold 20. In this embodiment, the double-crank type clamping device driven by the servo motor clamps the movable mold 10 and the fixed mold 20, and the clamping device can generate a clamping force of up to 4000 to 4500 kN. The servo motor has a power of 30 to 35 kW. The high clamping force ensures that no flashing occurs between the movable mold 10 and the fixed mold 20 during injection molding. The mechanical performance factor of the crankshaft is 35. As shown in FIG. 4, the screw 40 injects the molten material 50 into the cavity 30 at an injection speed of 600 to 1000 mm/sec (mm/s) and an injection pressure of 2000 to 4000 kgf/cm2 (kgf/cm2). in. 6 201018575 The injection pressure is preferably 3000 to 4000 kgf/cm, and the injection speed is preferably 80 to 1000 mm/sec. • Material 50 is polymethyl methyl acrylate (PMMA), polycarbonate (pc) or copolymerized cyclic hydrazine (C 〇 C). After the pressure in the cavity 3 is maintained and cooled for a while as shown in Fig. 5, the movable mold 1 and the fixed mold 2 are separated by the mold clamping device, and then the light guide plate 60 is taken out. The above process can produce a light guide plate having a thickness of 〇·4 to 0.8 mm (mm), especially a light guide plate having a thickness of 0.4 to 毫米6 mm. Taking PC as an example, when the injection pressure is 4000 kgf/cm, the thickness of the light guide plate 60 can reach 015 to 〇 6 mm. ^ Increasing the injection pressure can form a thin film, improve the injection speed, and can form a product with complex shape and thin thickness, which is beneficial to product stability and dimensional accuracy. In addition, due to the high injection pressure and injection speed, thinner products can be manufactured, which can save materials and reduce the volume of products using light guide plates. 6 In summary, the invention has indeed met the requirements of invention patents. File a patent application. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the present invention are intended to be included within the scope of the following claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flow chart of a method for injection molding a light guide plate according to an embodiment of the present invention. Fig. 2 is a schematic view showing an injection molding machine provided during the injection molding process of manufacturing a light guide plate according to an embodiment of the present invention. Fig. 3 is a schematic view showing the mold clamping process in the process of injection molding for manufacturing a light guide plate according to an embodiment of the present invention. Fig. 4 is a schematic view showing the injection material in the process of injection molding a light guide plate according to an embodiment of the present invention. Fig. 5 is a schematic view showing the extraction of the light guide plate in the process of injection molding a light guide plate according to an embodiment of the invention. [Main component symbol description] Dynamic mode 10 Fixed mode 20 Cavity 30 Screw 40 Material 50 Light guide plate 60