Joint Development of Ultra-Bright, Inorganic EL Light-Emitting Materials. November 2, 2005 KURARAY CO., LTD.

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1 Joint Development of Ultra-Bright, Inorganic EL Light-Emitting Materials November 2, 2005 KURARAY CO., LTD.

2 Sales Trends of Display-related Products (Kuraray (standalone)) FY1994 FY1999 FY2004 Sales Ratio Display-related products 3 Display-related products 6% Display-related products 15% Core products for display-related areas 97% Rear-projection TV screens Fresnel lens and a lenticular lens 94% Rear-projection TV screens Fresnel lens and a lenticular lens Films for polarizing plate 85% Rear-projection TV screens Fresnel lens and a lenticular lens Films for polarizing films Pellets for light guide plates Display-related products positioned as the priority business area; Concentrated R&D activity at Optical Device R&D Center

3 Structure of Liquid Crystal Display (LCD) and Cost Composition LCD Structure Black matrix Color filter Liquid crystal Transparent electrode (ITO) Source electrode Gate electrode Reflection/polarizing sheet Prism sheet Diffusion sheet Diffusion panel Amorphous silicon TFT Auxiliary electrode Pixel electrode Reduction of ancillary components and shortening of production process are key to cost reduction. Development of ways to reduce production costs of backlighting devices is particularly slow. Cost Composition Indirect cost Others 20% Protection film Polarizing film Protection film Retardation film 2 Retardation film 1 Facing glass substrate Transparent electrode (ITO) Protection membranes Gate insulation layer(sin) TFT glass substrate Facilities depreciation 15% Fluorescent light cold cathode tube Reflection panel Driver IC15% Backlighting devices 23% LC materials 3% Cost of components 65% Breakdown of cost of components (TFT) CF24% Glass substrates 18% Polarized plates, retardation films, etc. 17%

4 Comparison of Structure of Backlighting Device Using Light Guide Existing Backlighting Device Backlighting Device Using OP Film Polarized plate Liquid crystal panel Polarized plate Diffusion sheet Prism sheet Diffusion sheet Reflection sheet Light guide plate Dot-pattern Light source OP film OP film Light guide plate Total reflection Light guide plate

5 Development of Light Guide Backlighting Device Type Edge light type Back light type Area emission Shape Structure LED (Point light source) OP light guide Cold cathode tube (linear light source) OP light guide Cold cathode tube (linear light source) Diffusion panel EL (Area emission) Properties Thin. Low power consumption Thin. High brightness Ultra-thin. Low power consumption. Enables components integration. Applicatio n (Size) Cellular phones/pdas (2 5 ) Monitors (10 20 ) TVs (20 +) All purposes (all sizes)

liquid crystal using plastic film substrate (3 components) Glass substrate Color filter Orientation film TFT circuit Reflection

6 Research Subject TRADIM(Major project by METI) Establish roll-to-roll production process technologies to simplify components of liquid crystal panels Current: liquid crystal using glass substrate (30 layers/components) Polarizing film Retardation plate liquid crystal using plastic film substrate (3 components) Glass substrate Color filter Orientation film TFT circuit Reflection coating Glass substrate Retardation plate Polarizing film Backlight Liquid crystal using plastic film substrate Thin, light and flexible

7 What is Electroluminescence (EL)? >EL is a material which emits light when an electric current is passed through it same as light-emitting mechanism of a firefly. >In EL devices, light-emitting material is either vapor deposited or printed thinly on electrodes placed on glass substrates simple structure. >EL is self luminescent, bright, low energy consumption, high response speed, and environmentally friendly with no use of mercury. >Flexible displays can be produced by using plastic substrates. >Unlike light-emitting diode (LED), EL emits light by area emission and therefore is able to light a large area. Display Lighting if high brightness and long lifetime are achieved.

8 Types of Electroluminescence (EL) EL emits light by area emission which enables high resolution, production of thinner panels, low power consumption, and high response speed. LED emits light by point light sources (blue light-emitting material produced in single crystal: Difficult to make large-sized panels). Notable example: Nichia s blue LEDs Inorganic, LED metal compound, Organic EL organic compound EL light source Electric field excitation type Sealed with epoxy resin LED Carrier injection type LED crystal Inorganic EL particles Binder Inorganic EL Organic EL LED Inorganic thin film Diffusion type Low-molecular Polymer Crystals grow Coating Vapor deposition Coating Vapor deposition Coating Glass, etc. Transparent electrode EL luminous layer Metal electrode Structure of Inorganic EL and Organic EL

9 Challenges in Development of Electroluminescence (EL) Current big technological challenges: Brightness and lifetime (in blue EL materials in particular) Inorganic EL Low brightness (1,000cd/m2 or less); Shortage in capability of emitting blue light; Needs high voltage V). Organic EL Short life (tends to deteriorate easily because of its organic property); Weak capability of emitting blue light; High production cost. The ultimate light source IF the problems of low brightness and short lifetime (i.e. the trade-off relationship where raising brightness shortens lifetime) are solved. Current Properties of Display by Type Cathode Ray Tube Liquid Crystal Display Plasma Display Panel Electroluminescence (EL) CRT LCD PDP Inorganic EL Organic EL Image Quality Brightness Viewing angle Moving image Application to flatpanel TVs/displays Power consumption Product lifetime

10 Position of Ultra-bright Blue Inorganic EL T. CHATANI & CO., LTD. invented ultra-bright, inorganic EL light emitting materials Joint development with Kuraray Co., Ltd. Brightness cd/m 3 Lifetime hours Ultra-bright, inorganic EL material Inorganic EL Organic EL low-molecular type 350,000 25, ,000 1,000 10,000 Emits light at low voltage 5 6V: Works on batteries Ultra-bright with low heat generation Long lifetime Method employing coating enables production of large-area light sources. High stability against air and humidity Low production cost Ease of handling (production)

11 T. CHATANI & CO., LTD. Corporate Data T. CHATANI & CO., LTD. (Headquarters: Chuo-ku, Osaka) Established 1937 Capital 300 million (Unlisted) Financial results Net sales: 66 billion, (FY2004) Ordinary income: 280 million Business: Export, import and domestic trade of automobiles, industrial machinery & equipment, tires and other industrial and household goods. Manufacture and sales of backlighting devices (toll manufacturing)

12 Ultra-Bright Inorganic EL/Targeted Applications Light sources for displays 1 trillion LCD backlighting devices (firstly to be used as light source for MIRABRIGHT ) Emergency lights, traffic signs Lamps 4 trillion Traffic lights, car headlamps, commercial illumination Alternatives to incandescent lamps and fluorescent tubes Displays 10 trillion TVs Advertising billboards High brightness needed in large panels and lighting. Amount Market size (trillion yen) 1,400,000 1,200,000 1,000, , , , ,000 Back Light/Market Size 03 Year Market Size of Displays and Lighting LCD-TV Laptop Monitor Figures in are estimated global market sizes for Lighting Displays Sources: Techno Systems Research Co., Ltd.(04/4) OITDA(04/11)

Sep 09, APPLICATION NOTE 1193 Electronic Displays Comparison

Sep 09, APPLICATION NOTE 1193 Electronic Displays Comparison Sep 09, 2002 APPLICATION NOTE 1193 Electronic s Comparison Abstract: This note compares advantages and disadvantages of Cathode Ray Tubes, Electro-Luminescent, Flip- Dot, Incandescent Light Bulbs, Liquid