Vehicle Window Glass and Manufacturing Method Therefor

• US 20090080066A1
• Filed: 01/11/2007
• Published: 03/26/2009
• Est. Priority Date: 01/17/2006
• Status: Active Grant

• Current Assignee: Nippon Sheet Glass Company Limited (Nippon Telegraph and Telephone Corporation)
• Original Assignee: Nippon Sheet Glass Company Limited (Nippon Telegraph and Telephone Corporation)
• Inventors: Yoshida, Mamoru, Ogawa, Hisashi, Iwai, Nobuki, Muromachi, Takashi
• Granted Patent: US 8,445,096 B2
• Time in Patent Office: Days
• US Class Current: 359/359
• CPC Class Codes: B60J 1/00 Windows; Windscreens; Accessories therefor B60J10/00 takes precedence; air curtains instead of windows B60J9/04 ; sealing strips for windshields B60J10/70; sealing sash guides for sliding window panes B60J10/74; glass partitions inside vehicles to protect occupants against personal attack B60R21/12
• CPC Class Codes: C03C 17/002 for flat glass, e.g. float glass
• CPC Class Codes: C03C 17/007 containing a dispersed phase, e.g. particles, fibres or flakes, in a continuous phase
• CPC Class Codes: C03C 17/009 Mixtures of organic and inorganic materials, e.g. ormosils and ormocers
• CPC Class Codes: C03C 17/366 Low-emissivity or solar control coatings
• CPC Class Codes: C03C 2217/216 ZnO
• CPC Class Codes: C03C 2217/23 Mixtures
• CPC Class Codes: C03C 2217/231 In2O3/SnO2
• CPC Class Codes: C03C 2217/24 Doped oxides
• CPC Class Codes: C03C 2217/283 Borides, phosphides
• CPC Class Codes: C03C 2217/29 Mixtures
• CPC Class Codes: C03C 2217/475 Inorganic materials
• CPC Class Codes: C03C 2217/476 Tin oxide or doped tin oxide
• CPC Class Codes: C03C 2217/948 Layers comprising indium tin oxide [ITO]
• CPC Class Codes: C03C 2218/114 by brushing, pouring or doctorblading
• CPC Class Codes: Y10T 428/24479 including variation in thickness
• CPC Class Codes: Y10T 428/24612 Composite web or sheet
• CPC Class Codes: Y10T 428/24777 Edge feature

Abstract

There is provided a vehicle window glass that can be manufactured at low cost and can efficiently cut off infrared rays impinging on passengers sitting on window seats most susceptible to sunlight exposure, and a manufacturing method for the same. With a glass substrate 1 held by a glass substrate holding member 4 in the vertical direction, a nozzle 2 is used to eject an infrared cutoff liquid 3 onto the upper portion 1b of the glass substrate 1. The infrared cutoff liquid 3 ejected onto the upper portion 1b of the glass substrate 1 flows vertically downward such as to be applied onto the glass substrate 1. The film thickness of the lower portion of an infrared cutoff film is greater than that of the upper portion of the same. The glass substrate 1 is dried for approximately five minutes at room temperature. Then, the glass substrate 1 onto which the infrared cutoff liquid 3 has been applied is placed in an oven preheated to 200° C., heated for ten minutes, and then cooled so as to manufacture the glass substrate 1 having the infrared cutoff film thereon. The manufactured glass substrate 1 having the infrared cutoff film thereon is installed in a railroad vehicle 5 in such a way that the lower portion 1c of the glass substrate 1 is located on the lower side with respect to the railroad vehicle 5 and the upper portion 1b of the glass substrate 1 is located on the upper side with respect to the railroad vehicle 5.

Claims

1. A vehicle window glass comprising an infrared cutoff film formed thereon, wherein the film thickness of a vehicle lower side portion of said infrared cutoff film is greater than the film thickness of a vehicle upper side portion of the same.

2. The vehicle window glass according to claim 1, wherein said infrared cutoff film contains a silica component and an infrared cutoff component.

3. The vehicle window glass according to claim 2, wherein said infrared cutoff component is comprised of at least one of fine particles selected from the group consisting of tin-doped indium oxide (ITO) fine particles, antimony-doped tin oxide (ATO) fine particles, aluminum-doped zinc oxide (AZO) fine particles, indium-doped zinc oxide (IZO) fine particles, tin-doped zinc oxide fine particles, silicon-doped zinc oxide fine particles, lanthanum hexaboride fine particles, and cerium hexaboride fine particles.

4. The vehicle window glass according to claim 2, wherein the content of said infrared cutoff component is 20 to 45 mass % of the total mass of said infrared cutoff film.

5. The vehicle window glass according to claim 1, wherein the film thickness of said infrared cutoff film continuously varies from the vehicle upper side portion thereof to the vehicle lower side portion thereof.

6. The vehicle window glass according to claim 1, wherein the difference between the greatest film thickness of the vehicle lower side portion of said infrared cutoff film and the smallest film thickness of the vehicle upper side portion of the same is 1000 nm or greater.

7. The vehicle window glass according to claim 1, wherein the greatest film thickness of the vehicle lower side portion of said infrared cutoff film is not smaller than twice the smallest film thickness of the vehicle upper side portion of the same.

8. The vehicle window glass according to claim 1, wherein a thinnest part of the vehicle upper side portion of said infrared cutoff film has an optical transmittance of 30% or lower within the wavelength range from 1000 to 1600 nm and an optical transmittance of 20% or lower within the wavelength range from 1600 to 2500 nm, and a thickest part of the vehicle lower side portion of said infrared cutoff film has an optical transmittance of 20% or lower within the wavelength range from 1000 to 1600 nm and an optical transmittance of 10% or lower within the wavelength range from 1600 to 2500 nm.

9. The vehicle window glass according to claim 1, wherein the 1550 nm wavelength optical transmittance of a thickest part of the vehicle lower side portion of said infrared cutoff film where the film thickness is the greatest is not higher than 50% of the 1550 nm wavelength optical transmittance of a thinnest part of the vehicle upper side portion of said infrared cutoff film where the film thickness is the smallest.

10. A production method for a vehicle window glass on which an infrared cutoff film is formed, the method comprising the forming step of forming the infrared cutoff film by applying an infrared cutoff liquid onto the surface of a glass substrate by using flow coating in such a way that the film thickness of a vehicle lower side portion of the infrared cutoff film is greater than the film thickness of a vehicle upper side portion of the same.