200900744 九、發明說明: 【發明所屬之技術領域】 本發明係關於液晶顯示器中背光模組之元件-散射膜及使 用此散射膜片之背光模組 【先前技術】 液晶顯不器中主要由液晶層5和背光模組11所構成,液晶 層由薄膜電晶體7、液晶8、彩色濾光片6,上下二面再夾著 上偏光片9、下偏光片10組成,光線藉由薄膜電晶體6之電 流通過,控制液晶8之旋轉角度,讓光線通過液晶6,而顯 示於螢幕上。由於液晶層5自身並不發光,光源來自下層背 光模組11。如圖二背光模組11主要光學構件有燈管15、反 射片16、棱鏡片12、散射膜13、導光板14。光源從燈管15, 呈圓柱狀向四周射出,經導光板14,使光線轉向散射膜13 ’ 再由散射膜13將光線散射分散,由原本之單向光線經由散射 膜之作用呈曲面散開,再進入稜鏡片12,稜鏡片12使曲面 散開之光線再往正面集合,使正上方光線分佈呈現峰値。光 線透過上散射膜13a散射後,再向液晶層5前進。近夂 射膜13a已甚小使用。 又圖三,LED發光層或燈管層17,LED爲發光二極體由 多顆LED排歹値線架設於單排構件上,再由多個單排之LED 構件平行排列成一平面光源,或由多排燈管組成之燈管層。 如LED發光層或燈管層17,LED之數量取決於平面之大小’ 200900744 光源強度之需求等,而由不同數目之led或不同數量之燈管 組合。光線直接由LED發光層或燈管層17進入散射膜13, 再由散射膜13將光線呈曲面散開,再進入稜鏡片12,使曲 面散開之光線,再往正面集合,使正上方光線分佈呈現峰値。 依上述圖二、圖三光源之路徑,及解決光源分散之方法一 散射膜13。散射膜13依實際散射均勻的需要有單片或多片 散射膜13之堆疊組合,使達到均勻之效果,一般單層散射膜 如圖四所示,單層散射膜18,由出光面散射層20,基材片 19,黏附防上層21所組成,只具備單層之散射功能,對背光 模組11、13而言,單層散射膜18所提供之散射功能有限, 在整體之均勻表現,必需依靠多片單層散射膜堆疊才能有較 好的呈現。在整體組裝過程中產生較多之工序,造成生產過 程中,虛耗大量工時,亦容易產生失誤、不良品之升高。 200900744 【發明内容】 雙層散射膜1是由基材膜片2,再在基材膜片2之二側表 面,分別塗上出光散射層3及入光散射層4所組成,如圖一 所示。 基材膜片2必需爲無色透明的合成樹脂形成,所用的合成樹 脂並沒有特殊之限制,只要合成樹脂在薄膜成型後,厚度均 勻,機械、化學及光學性質優良,即可使用。一般常用基材 f 膜片2,如聚對苯二甲酸乙二醇酯、丙烯酸樹脂、聚碳酸酯、 聚對萘二甲酸乙二醇酯、聚苯乙烯、聚烯烴、纖維素乙酸酯 等。在雙層散射膜1最常用者爲聚對苯二甲酸乙二醇酯,簡 稱PET,使用厚度約在38/zm〜300//m間,常用厚度有100 /zm、150//m、188/zm等,薄膜二側表面必需經過表面處理, 一般常用的處理方式爲接著劑處理。 出光散射層3及入光散射層4,是由接合劑23及分散於接 ( 合劑23內之珠狀顆粒22構成。接合劑23可爲單一型樹脂或 二種以上樹脂混合而成,一般常用有熱固型樹脂、紫外線硬 化型樹脂或電離放射線硬化樹脂,球狀顆粒22均勻密佈於接 合劑中,在接合劑23塗佈於基材片2表面成型後,球狀顆粒 22突出表面,形成各曲型表面,稱之爲微型散射界面。接合 劑23 —般採用光線容易穿過之樹脂’·氨酸樹脂、聚甲基丙烯 酸甲酯、聚胺基甲酸乙酯樹脂、氧樹脂等,因應塗佈之製造200900744 IX. Description of the Invention: [Technical Field] The present invention relates to a component-scattering film of a backlight module in a liquid crystal display and a backlight module using the same. [Prior Art] A liquid crystal display is mainly composed of a liquid crystal The layer 5 and the backlight module 11 are formed. The liquid crystal layer is composed of a thin film transistor 7, a liquid crystal 8, and a color filter 6, and the upper and lower sides are sandwiched between the upper polarizer 9 and the lower polarizer 10, and the light is passed through the thin film transistor. The current of 6 passes, and the rotation angle of the liquid crystal 8 is controlled, so that the light passes through the liquid crystal 6, and is displayed on the screen. Since the liquid crystal layer 5 itself does not emit light, the light source is from the lower layer backlight module 11. As shown in FIG. 2, the main optical components of the backlight module 11 include a lamp tube 15, a reflection sheet 16, a prism sheet 12, a scattering film 13, and a light guide plate 14. The light source is emitted from the lamp tube 15 in a cylindrical shape, and is guided to the periphery by the light guide plate 14, so that the light is diverted to the scattering film 13', and then the light is scattered and dispersed by the scattering film 13, and the unidirectional light is scattered by the scattering film. Then enter the cymbal 12, and the cymbal 12 causes the scattered light of the curved surface to gather toward the front side, so that the light distribution on the upper side presents a peak. The light is scattered by the upper scattering film 13a and then proceeds to the liquid crystal layer 5. The near 射 film 13a has been used very little. 3, the LED light-emitting layer or the tube layer 17, the LED is a light-emitting diode arranged by a plurality of LED rows and wires on a single row of members, and then a plurality of single-row LED members are arranged in parallel to form a planar light source, or A layer of tubes consisting of multiple rows of tubes. For example, the LED light-emitting layer or the tube layer 17, the number of LEDs depends on the size of the plane '200900744 light source intensity requirements, etc., but by a different number of led or a different number of lamps combined. The light enters the scattering film 13 directly from the LED light-emitting layer or the tube layer 17, and then the light is scattered on the curved surface by the scattering film 13, and then enters the cymbal 12, so that the light scattered on the curved surface is collected on the front side, so that the light distribution is directly above. Peak. According to the above-mentioned FIG. 2, FIG. 3, the path of the light source, and the scattering film 13 of the method for solving the dispersion of the light source. The scattering film 13 has a stacking combination of a single sheet or a plurality of scattering films 13 in order to achieve uniform uniformity in order to achieve uniformity. Generally, a single-layer scattering film is shown in FIG. 4, and a single-layer scattering film 18 is provided by a light-emitting surface scattering layer. 20, the substrate sheet 19, adhered to the upper layer 21, only has a single layer of scattering function, for the backlight modules 11, 13, the single layer of scattering film 18 provides limited scattering function, uniform performance in the overall, It is necessary to rely on multiple single-layer scattering film stacks for better presentation. In the overall assembly process, more processes are generated, resulting in a lot of man-hours in the production process, and it is also prone to errors and defective products. 200900744 [Summary of the Invention] The double-layered scattering film 1 is composed of a substrate film 2 and then coated on both sides of the substrate film 2, respectively, with a light-scattering layer 3 and a light-scattering layer 4, as shown in FIG. Show. The base film 2 must be formed of a colorless transparent synthetic resin, and the synthetic resin to be used is not particularly limited as long as the synthetic resin is uniform in thickness after film formation, and is excellent in mechanical, chemical, and optical properties. Generally used substrate f film 2, such as polyethylene terephthalate, acrylic resin, polycarbonate, polyethylene naphthalate, polystyrene, polyolefin, cellulose acetate, etc. . In the double-layer scattering film 1, the most common one is polyethylene terephthalate, abbreviated as PET, and the thickness is about 38/zm~300//m. The common thickness is 100/zm, 150//m, 188. /zm, etc., the two sides of the film must be surface treated, the usual treatment is the adhesive treatment. The light-emitting scattering layer 3 and the light-in scattering layer 4 are composed of a bonding agent 23 and bead particles 22 dispersed in the bonding agent 23. The bonding agent 23 may be a single resin or a mixture of two or more resins, and is generally used. The thermosetting resin, the ultraviolet curable resin, or the ionizing radiation hardening resin, the spherical particles 22 are uniformly densely mixed in the bonding agent, and after the bonding agent 23 is applied on the surface of the substrate sheet 2, the spherical particles 22 protrude from the surface to form Each curved surface is called a micro-scattering interface. The bonding agent 23 generally uses a resin which is easy to pass through, such as a resin, a polymethyl methacrylate, a polyurethane resin, an oxygen resin, etc. Coating manufacturing
S 200900744 需要,可加入消泡劑、分散劑 '安定劑、固化劑等配合使用, 珠狀II粒22,接近球狀或隨圓球之結構,可讓光線透過,一 般使用透明的材料,如二氧化矽、丙烯酸樹脂、聚對苯二甲 酸乙二醇脂、聚甲基丙烯酸甲酯等。珠狀顆粒22粒徑大小約 0.5//m〜60/zm爲佳,最常使用之範圍爲約2//m〜40⑽, 因產生之微型散射界面較爲理想。 @^散射界面是由凸出的珠狀顆粒22之表面形成,由於是 曲形之表面’利用該曲形表面作光線的散射,如圖六,當光 線經過凸形曲面時,先作內聚,再往外散射,此爲入光散射 層4之凸形微型散射界面24之作用。而光線經凸形微型散射 界面24散射出無數光線(圖六僅以三條光線代表無數光線) 後,穿透基材膜片2後進入出光散射層4 〇如圖七所示,當 光線進入凹形曲面時,直接向外散射,此爲出光散射面之凹 形微型散射界面25之作用。 出光散射層3及入光散射層4,是由接合劑23及分散於接 合劑23內之珠狀顆粒22構成,而出光散射層3及入光散射 層4之樹脂,在塗佈過程中,熱固型樹脂紫外電離常含有一 種或以上之樹脂溶劑組成。如甲苯、丙酮、丁酮、甲丙醇、 乙二醇、乙醚、乙酯等有機溶劑。製程中,經過烤箱加熱升 溫,有機溶劑揮發,餘下接合劑23和珠狀顆粒22起交聯作 用,而牢靠在基材膜片2上,因珠狀顆粒22包含大小不同粒 200900744 徑,表面之珠狀顆粒22,凸出表面形成凸形微型散射界面24 及凹形微型散射界面25,而埋藏於出光散射層3及入光散射 層4中之珠狀顆粒22,在內部作交聯作用,使出光散射層3 及入光散射層4之硬度增加,強度增加,耐熱度也升高。 珠狀顆粒22,常用材料有二氧化矽、石英、二氧化鈦、丙 烯酸樹脂、聚氨酯樹脂、聚苯乙烯、聚碳酸酯等透明度優良 之有機化合物或無機化合物構成。由於珠狀顆粒22在塗佈製 程易與接合劑23起交聯作用,固此內部安定。珠狀顆粒22 均勻密佈於出光散射層3,及入光散射層4中。珠狀顆粒22, 可採均勻密佈處理或均勻分佈處理,分佈之密度約爲10%〜 100%,珠狀顆粒22在入光散射層4及出光散射層3之大小可 以爲相同之粒徑,亦可爲不同之粒徑,通常出光散射層稍大。 出光散射層3及入光散射層4之厚度。因不同之需要,而 有不同之變化,二層分別可用相同之厚度及不同之厚度。二 層之珠狀顆粒22分別可爲相同或不同之有機化合物或無機 物組成,亦可有機物及無機物混合共同使用。二層之珠狀顆 粒22之各成份亦可爲相同或不相同。 200900744 【實施方式】 由滾軸式連續生產設備生產。基材膜片捲材架設於送捲軸 上。當捲材沿生產線至塗佈設備時。塗佈頭(刮刀式、鈷木輪 式、精密模擠出式等)將樹脂(熱固型棚旨、紫外線硬化型棚旨 或電離放射線硬化樹脂)依調整之厚度均勻塗佈於捲材膜上, 再經由烤箱加溫,或再加紫外線設備固化後,再由收捲軸收回 成捲材。再依相同方式處理另一面之膜面。二面經塗佈之捲材 再經切割機切成所需尺寸後供使用。雙層散射膜片成品之規格 必需通過ASTM D1003之光學測試標準。光學透過爲60%以 上,霧度爲80%以上。 【圖式簡單說明】 圖1係本發明雙層散射膜之一實施形態截面示意圖。 圖2係一般側光燈源液晶顯示器之截面示意圖。 圖3係一般直下式液晶顯示器之截面示意圖。 圖4係一般單層散射膜之截面示意圖。 圖5係本發明雙層散射膜之光線通過散射層之截面示意圖。 I 圖6係凹形微型散射器之截面示意圖。 圖7係凸形微型散射器之截面示意圖。 11 200900744 【主要元件符號說明】 1. 雙層光散射膜 2. 基材膜片 3. 出光散射膜 4. 入光散射膜 5. 液晶層 6. 彩色濾光片 7. 薄膜電晶體 8. 液晶 9. 上偏光片 10. 下偏光片 11. 背光模組 12. 稜鏡片 13. 散射膜 13a. 上散射膜 14. 導光板 15. 燈管 16. 反射片 17. LED發光層 18. 單層散射膜 19. 基材膜片 20. 出光面散射層 200900744 21. 黏附防止層 22. 珠狀顆粒 23. 接合劑 24. 凹形微型散射氣截面 25. 凸形微型散射氣截面 13S 200900744 Needed, can be added with antifoaming agent, dispersing agent 'stabilizer, curing agent, etc., bead II II 22, close to the spherical or with the structure of the ball, allowing light to pass through, generally using transparent materials, such as Ceria, acrylic resin, polyethylene terephthalate, polymethyl methacrylate, and the like. The beaded particles 22 preferably have a particle size of about 0.5/m to 60/zm, and the most commonly used range is from about 2/m to 40 (10), which is preferable because of the resulting micro-scattering interface. The @^ scattering interface is formed by the surface of the convex bead-shaped particles 22, since the curved surface is used for scattering of light by the curved surface, as shown in Fig. 6, when the light passes through the convex curved surface, it is first cohesive. And then scatter outward, which acts as a convex micro-scattering interface 24 into the light scattering layer 4. The light scatters a myriad of light through the convex micro-scattering interface 24 (the three rays represent only a myriad of light), and then penetrates the substrate film 2 and enters the light-scattering layer 4, as shown in Figure 7, when the light enters the concave When the curved surface is formed, it directly scatters outward, which is the function of the concave micro-scattering interface 25 of the light-scattering surface. The light-emitting scattering layer 3 and the light-in scattering layer 4 are composed of the bonding agent 23 and the bead-like particles 22 dispersed in the bonding agent 23, and the light-scattering layer 3 and the resin that enters the light-scattering layer 4 are applied during the coating process. Thermosetting resin UV ionization often contains one or more resin solvents. Such as toluene, acetone, methyl ethyl ketone, methyl propanol, ethylene glycol, ether, ethyl ester and other organic solvents. During the process, the temperature is raised by heating in the oven, the organic solvent is volatilized, and the remaining bonding agent 23 and the beaded particles 22 are cross-linked, and are firmly adhered to the substrate film 2, since the bead-shaped particles 22 contain different diameters of the particles 200900744, the surface The bead-shaped particles 22 have a convex micro-scattering interface 24 and a concave micro-scattering interface 25, and the bead-like particles 22 buried in the light-scattering layer 3 and the light-scattering layer 4 are internally cross-linked. The hardness of the light-scattering layer 3 and the light-scattering layer 4 is increased, the strength is increased, and the heat resistance is also increased. The beaded particles 22 are usually composed of an organic compound or an inorganic compound having excellent transparency such as cerium oxide, quartz, titanium oxide, acrylic resin, urethane resin, polystyrene or polycarbonate. Since the beaded particles 22 are easily crosslinked with the bonding agent 23 in the coating process, the interior is stabilized. The beaded particles 22 are uniformly densely attached to the light-emitting scattering layer 3 and into the light-scattering layer 4. The beaded particles 22 can be uniformly densely treated or uniformly distributed, and the density of the distribution is about 10% to 100%, and the size of the beaded particles 22 in the light scattering layer 4 and the light scattering layer 3 can be the same. It can also be a different particle size, and the light scattering layer is usually slightly larger. The thickness of the light-scattering layer 3 and the light-scattering layer 4. Due to different needs, there are different changes, the same thickness and thickness can be used for the second layer. The two-layered beaded particles 22 may be composed of the same or different organic compounds or inorganic substances, and may be used in combination of organic substances and inorganic substances. The components of the second layer of beaded particles 22 may be the same or different. 200900744 [Embodiment] It is produced by roller type continuous production equipment. The substrate film roll is mounted on a take-up reel. When the coil is along the production line to the coating equipment. The coating head (scraper type, cobalt wood wheel type, precision mold extrusion type, etc.) uniformly applies the resin (the thermosetting type, the ultraviolet curing type or the ionizing radiation curing resin) to the coil film in accordance with the adjusted thickness. On the top, and then heated through the oven, or after adding UV equipment to cure, and then retracted into a coil by the take-up reel. The film side of the other side is treated in the same manner. The coated web on both sides is cut into the required size and used for cutting. The specifications of the two-layer scattering diaphragm finished product must pass the optical test standard of ASTM D1003. The optical transmission is 60% or more, and the haze is 80% or more. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view showing an embodiment of a double-layered scattering film of the present invention. 2 is a schematic cross-sectional view of a general sidelight source liquid crystal display. 3 is a schematic cross-sectional view of a general direct type liquid crystal display. Figure 4 is a schematic cross-sectional view of a general single-layer scattering film. Figure 5 is a schematic cross-sectional view showing the light passing through the scattering layer of the double-layered scattering film of the present invention. I Figure 6 is a schematic cross-sectional view of a concave micro-scatterer. Figure 7 is a schematic cross-sectional view of a convex micro-scatterer. 11 200900744 [Description of main components] 1. Double-layer light scattering film 2. Substrate film 3. Light-emitting scattering film 4. Light-scattering film 5. Liquid crystal layer 6. Color filter 7. Thin-film crystal 8. Liquid crystal 9. Upper polarizer 10. Lower polarizer 11. Backlight module 12. Backsheet 13. Scattering film 13a. Upper diffusing film 14. Light guide plate 15. Lamp tube 16. Reflecting sheet 17. LED light emitting layer 18. Single layer scattering Film 19. Substrate film 20. Light-emitting surface scattering layer 200900744 21. Adhesion preventing layer 22. Beaded particles 23. Bonding agent 24. Concave micro-scattering gas section 25. Convex micro-scattering gas section 13