Light condensing film, liquid-crystal panel and backlight a well as manufacturing process for light-condensing film

• US 20060279679A1
• Filed: 12/08/2004
• Published: 12/14/2006
• Est. Priority Date: 07/16/2004
• Status: Active Grant

• Current Assignee: Kuraray Company Limited
• Original Assignee: Dainippon Ink and Chemicals Incorporated, Dai Nippon Printing Company Limited, JSR Corporation, Konica Minolta Holdings Incorporated (Konica Minolta Inc.), Kuraray Company Limited, NEC Corporation, Hitachi Chemical Company Limited (Resonac Holdings Corp.), Sumitomo Bakelite Company Limited, Sumitomo Chemical Company Limited, Toppan Printing Co., Ltd. (TOPPAN Holdings, Inc.), Toray Industries Incorporated
• Inventors: Takechi, Kazushige, Sumiyoshi, Ken, Tsukuda, Akimitsu, Ono, Yoshiyuki, Suzuki, Motoyuki, Takahashi, Tatsumi, Yonehara, Hisatomo, Tsuruoka, Yasuo, Matsuoka, Yoshiki, Fujieda, Ichiro, Eguchi, Toshimasa, Sekine, Norimasa, Oshima, Noboru, Ikari, Tokuo, Genda, Kazuo, Kumano, Atsushi, Yamaoka, Shigenori, Fujisawa, Katsuya
• Granted Patent: US 7,852,435 B2
• Time in Patent Office: Days
• US Class Current: 349/116
• CPC Class Codes: B32B 2307/40 having particular optical properties light or UV resistant B32B2307/71
• CPC Class Codes: B32B 2457/20 Displays, e.g. liquid crystal displays, plasma displays
• CPC Class Codes: B32B 2457/202 LCD, i.e. liquid crystal displays
• CPC Class Codes: G02B 5/0221 the surface having an irregular structure G02B5/0226 takes precedence
• CPC Class Codes: G02B 5/0242 by means of dispersed particles
• CPC Class Codes: G02B 5/0268 characterized by the fabrication or manufacturing method
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G02B 5/0284 used in reflection
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• CPC Class Codes: G02F 1/133607 the light controlling member including light directing or refracting elements, e.g. prisms or lenses
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor

Abstract

A conventional liquid crystal display comprises a number of components, so that a manufacturing cost cannot be reduced. Furthermore, a large-area substrate has problems in shipping. According to this invention, a liquid-crystal panel is prepared by forming individual optically functional films, a TFT device and a light-emitting device on a long thin film and then laminating the film by a transfer process. A base film to be a substrate in a liquid-crystal panel preferably has a thickness of 10 μm to 200 μm, a curvature radius of 40 mm or less as a measure of flexibility and a coefficient of thermal expansion of 50 ppm/° C. or less. Furthermore, it more preferably gives a variation of ±5% or less in mechanical and optical properties to a thermal history at 200° C.

Claims

1. A light-condensing layered film comprising at least a light-condensing film and a long light-guiding film, wherein

the light-condensing film comprises an array of light collectors made of an organic resin is formed on a long light-diffusing film with a flexibility of 40 mm or less of a curvature radius and a coefficient of thermal expansion of 50 ppm/°

C. or less and

a surface in the light collector facing the surface contacting with the light-diffusing film is flat and has a smaller area than the surface contacting with the light-diffusing film, and

the light-guiding film is laminated, on the surface facing the light diffusing film in the light collection in the light-condensing film.

31. The light-condensing layered film as claimed in claim 1, wherein

the light-guiding film has a coefficient of thermal expasion of 50 ppm/°

C. or less.

10. (canceled)

25. A process for manufacturing a light-condensing layered film comprising the steps of

filling an irregularity in a support corresponding to the irregularity of the light collector with an organic resin, and

transferring the filling resin to the long light-diffusing thin film and formed the irregularity of light corrector on the light-condensing film and,

laminating a long light-guiding film on a surface in the light corrector facing the surface contacting with the light-diffusing layered film.

a light-guiding film is laminated, on the surface facing the light diffusing film in the irregularity of light collector in the light-condensing film.

26. A process for manufacturing a light-condensing layered film comprising the steps of

forming a thin film made of an organic resin on a long light-diffusing film and

transferring an irregularity of the light collector to the thin film and

a light-guiding film is laminated, on the surface facing the light diffusing film in the irregularity of light collector in the light-condensing film.

27. The process for manufacturing a light-condensing layered film as claimed in claim 26, wherein the transfer step is pressing a template having a shape of the irregularity in the light collector.

28. The process for manufacturing a light-condensing layered film as claimed in claim 26, wherein the step of transferring the light collector comprises the step of curing the organic resin under pressure.

29. The process for manufacturing a light-condensing layered film as claimed in claim 28, wherein the organic resin is cured by UV-ray irradiation.

30. (canceled)

32. A light-condensing layered film comprising at least a light-condensing film and a long light-guiding film, wherein

the light-condensing film comprises an array of light collectors made of an organic resin is formed on a long light-diffusing film with a flexibility of 40 mm or less of a curvature radius and a coefficient of thermal expansion of 50 ppm/°

C. or less and

a surface in the light collector facing the surface contacting with the light-diffusing film is flat and has a smaller area than the surface contacting with the light-diffusing film, and

the light-guiding film is laminated, on the surface facing the light diffusing film in the light collector in the light-condensing film, with the light-guiding film having a coefficient of thermal expansion of 50 ppm/°

C. or less.

2. The light-condensing layered film as claimed in claim 32, wherein the light-diffusing film has a Young'"'"'s modulus of 1.5 GPa or more.

3. The light-condensing layered film as claimed in claim 32, wherein the light-diffusing film is fed from a first roll to a second roll, during which a thin film can be formed on its surface.

4. The light-condensing layered film as claimed in claim 32, wherein the light-diffusing film has a variation in mechanical and optical properties of ±

5% or less to a thermal history at 200°

C.

5. The light-condensing layered film as claimed in claim 32, wherein the light-diffusing film has a variation in mechanical and optical properties of ±

5% or less to a thermal history at 250°

C.

6. The light-condensing layered film as claimed in claim 32, wherein the light-diffusing film comprises transparent light-diffusing particles with a refractive index different from that of the film.

7. The light-condensing layered film as claimed in claim 6, wherein the transparent particle is zinc oxide, ITO or silica and has a particle size of 0.5 μ

m or more and ½

or less of the film thickness.

8. The light-condensing layered film as claimed in claim 32, wherein the light-diffusing film and the light collector are made of the same resin.

9. The light-condensing layered film as claimed in claim 8, wherein the resin is selected from an acrylic resin and a cyclic olefin resin.

11. The light-condensing layered film as claimed in claim 32, wherein the light-guiding film has a Young'"'"'s modulus of 1.5 GPa or more.

12. The light-condensing layered film as claimed in claim 32, wherein the light-guiding film is fed from the first roll to the second roll, during which the light-condensing film is laminated with the surface facing the light diffusing film in the light collector.

13. The light-condensing layered film as claimed in claim 32, wherein the light-guiding film has a variation in mechanical and optical properties of ±

5% or less to a thermal history at 200°

C.

14. The light-condensing layered film as claimed in claim 32, wherein the light-guiding film has a variation in mechanical and optical properties of ±

5% or less to a thermal history at 250°

C.

15. The light-condensing layered film as claimed in claim 32, wherein the light-guiding film comprises an inorganic fillers.

16. The light-condensing layered film as claimed in claim 15, wherein a particle size of the inorganic fillers is 1 nm to 380 nm.

17. The light-condensing layered film as claimed in claim 16, wherein the inorganic fillers is made of a material selected from titanium dioxide, zinc oxide, alumina and silicon oxide.

18. The light-condensing layered film as claimed in claim 32, wherein the light-guiding film has a light transmittance of 80% or more.

19. The light-condensing layered film as claimed in claim 32, wherein the light-guiding film is made of an acrylic resin or a cyclic olefin resin.

20. The light-condensing layered film as claimed in claim 32, wherein the light-diffusing film, the light collector and the light-guiding film are made of the same resin.

21. The light-condensing layered film as claimed in claim 20, wherein the resin is an acrylic resin or a cyclic olefin resin.

22. A light-condensing layered film as claimed in claim 32, wherein an oriented film and a transparent counter electrode are formed on the light-diffusing film.

23. A liquid-crystal panel comprising;

the light-condensing layered film as claimed in claim 22 and a liquid crystal functional thin film having an optical functional thin film, an oriented film and a pixel electrode, wherein

each oriented film in the light-condensing layered film and in the liquid crystal functional film are disposed, facing each other, and a liquid crystal is sandwiched between the oriented films.

24. A backlight comprising:

wherein

the light-condensing layered film as claimed in claim 32 is divided into desired shape pieces.

33. The backlight as claimed 24, wherein

a light source is placed adjacently to at least one plane substantially perpendicular to the plane on which the light collector in the optical guide is placed.

34. The process for manufacturing a light-condensing layered film as claimed 25, wherein

the step of transferring the filling resin to the long light-diffusing thin film and formed an array of light correctors on the light-condensing film comprises the step of curing the organic resin under pressure.