Substrate provided with antireflection films and its production method

• US 20020051294A1
• Filed: 07/26/2001
• Published: 05/02/2002
• Est. Priority Date: 07/27/2000
• Status: Active Grant

• Current Assignee: Asahi Glass Company, Limited (AGC, Inc.)
• Original Assignee: Asahi Glass Company, Limited (AGC, Inc.)
• Inventors: Maekawa, Mikako, Shidoji, Eiji, Kimura, Yukio, Noda, Kazuyoshi, Katayama, Yoshihito
• Granted Patent: US 6,570,709 B2
• Time in Patent Office: Days
• US Class Current: 359/586
• CPC Class Codes: C03C 17/3417 all coatings being oxide coatings
• CPC Class Codes: C03C 17/3435 comprising a nitride, oxynitride, boronitride or carbonitride
• CPC Class Codes: C03C 17/3441 comprising carbon, a carbide or oxycarbide
• CPC Class Codes: C03C 2217/734 comprising an alternation of high and low refractive indexes
• CPC Class Codes: G02B 1/115 Multilayers

Abstract

It is to provide a substrate provided with antireflection films, which is excellent in antireflection properties to incident light at an oblique angle from the film face side, which has a high transmittance and with which the reflection color tone does not tend to be bluish.

A substrate provided with antireflection films, which comprises a transparent substrate and at least two antireflection film layers deposited on one side of the transparent substrate,

wherein the reflectance on the film face of light incident at an angle of incidence of 5° from the film face side is at most 6% at the entire wavelength region ranging from 400 to 480 nm.

Claims

1. A substrate provided with antireflection films, which comprises a transparent substrate and at least two antireflection film layers deposited on one side of the transparent substrate,

wherein the reflectance on the film face of light incident at an angle of incidence of 50 from the film face side is at most 6% at the entire wavelength region ranging from 400 to 480 nm.

3. The substrate provided with antireflection films according to claim 1, which comprises a transparent substrate and first and second antireflection film layers deposited in this order on one side of the transparent substrate,

wherein the first layer is a thin film having a refractive index of from 1.6 to 2.6 and a geometrical film thickness of from 60 to 200 nm;

and

the second layer is a thin film having a refractive index of from 1.4 to 1.56 and a geometrical film thickness of from 50 to 140 nm.

4. The substrate provided with antireflection films according to claim 1, which comprises a transparent substrate and first and second antireflection film layers deposited in this order on one side of the transparent substrate,

wherein the first layer is a thin film containing an oxide, an oxynitride or an oxycarbide of at least one element selected from the group consisting of titanium, silicon, zinc, aluminum, tin, zirconium, tantalum, tungsten, bismuth and niobium, or a nitride or a nitrogen carbide of at least one element selected from the group consisting of silicon, aluminum and boron.

5. The substrate provided with antireflection films according to claim 1, which comprises a transparent substrate and first and second antireflection film layers deposited in this order on one side of the transparent substrate,

wherein the second layer is a thin film containing an oxide of silicon.

8. The substrate provided with antireflection films according to claim 1, which comprises a transparent substrate and first, second and third antireflection film layers deposited in this order on one side of the transparent substrate

wherein the first and second layers are thin films having compositions which are different from each other, each having a refractive index of from 1.6 to 2.5, and at least one of the first and second layers having a geometrical film thickness of from 2 to 95 nm;

and

the third layer is a thin film having a refractive index of from 1.4 to 1.5 and a geometrical film thickness of from 44 to 138 nm.

9. The substrate provided with antireflection films according to claim 1, which comprises a transparent substrate and first, second and third antireflection film layers deposited in this order on one side of the transparent substrate,

wherein the first and second layers are thin films having compositions which are different from each other, each containing an oxide, an oxynitride or an oxycarbide of at least one element selected from the group consisting of titanium, silicon, zinc, aluminum, tin, zirconium, tantalum, tungsten, bismuth and niobium, or a nitride or a nitrogen carbide of at least one element selected from the group consisting of silicon, aluminum and boron.

10. The substrate provided with antireflection films according to claim 1, which comprises a transparent substrate and first, second and third antireflection film layers deposited in this order on one side of the transparent substrate,

wherein the third layer is a thin film containing an oxide of silicon.

13. The substrate provided with antireflection films according to claim 1, which comprises a transparent substrate and first, second and third antireflection film layers deposited in this order on one side of the transparent substrate,

wherein the total thickness of the three antireflection film layers (sum of the film thicknesses of the first, second and third layers) is less than 250 nm.

14. The substrate provided with antireflection films according to claim 1, wherein each layer has an extinction coefficient of at most 0.05 at the visible light region.

15. A method for producing a substrate provided with antireflection films, which comprises subjecting the substrate provided with antireflection films as defined in claim 1 to a heat treatment to produce the substrate provided with antireflection films having bending or tempering applied thereto.

16. A method for producing a laminated glass, which comprises subjecting the substrate provided with antireflection films as defined in claim 1 wherein the transparent substrate is glass, to bending into a three-dimensional curved shape by a heat treatment, and laminating the glass substrate provided with antireflection films subjected to bending and another glass substrate having approximately the same shape by means of an intermediate film.

17. A window glass for an automobile which uses the substrate provided with antireflection films as defined in claim 1.

2. A substrate provided with antireflection films, which comprises a transparent substrate and first and second antireflection film layers deposited in this order on one side of the transparent substrate,

wherein the first layer is a thin film having a refractive index of from 1.6 to 2.6 and a geometrical film thickness of from 1.1 to 1.9 times the film thickness as an antireflection condition as obtained from the following formula;

and

the second layer is a thin film having a refractive index of from 1.4 to 1.56 and a geometrical film thickness of from 0.5 to 1.1 times the film thickness as an antireflection condition as obtained from the following formula;

d=λ

/[4n(1−

(sinθ

/n)²}^1/2]

wherein d is a film thickness as an antireflection condition of each layer, n is a refractive index of each layer, λ

=550 nm and θ

=60°

.

6. A substrate provided with antireflection films, which comprises a transparent substrate and first and second antireflection film layers deposited in this order on one side of the transparent substrate,

wherein the first layer is a tin oxynitride film having a geometrical film thickness of from 104 to 124 nm;

and

the second layer is a silicon oxide film having a geometrical film thickness of from 85 to 105 nm.

7. A substrate provided with antireflection films, which comprises a transparent substrate and first, second and third antireflection film layers deposited in this order on one side of the transparent substrate,

wherein the first and second layers are thin films having compositions which are different from each other, each having a refractive index of from 1.6 to 2.5, and at least one of the first and second layers having a geometrical film thickness of from 0.04 to 0.9 time the film thickness as an antireflection condition as obtained from the following formula;

and

the third layer is a thin film having a refractive index of from 1.4 to 1.5 and a geometrical film thickness of from 0.4 to 1.1 times the film thickness as an antireflection condition as obtained from the following formula;

d=λ

/[4n(1−

(sinθ

/n)²}^1/2]

wherein d is a film thickness as an antireflection condition of each layer, n is a refractive index of each layer, λ

=550 nm and θ

=60°

.

11. A substrate provided with antireflection films, which comprises a transparent substrate and first, second and third antireflection film layers deposited in this order on one side of the transparent substrate,

wherein the first layer is a tin oxynitride film having a geometrical film thickness of from 70 to 130 nm, the second layer is a titanium oxide film having a geometrical film thickness of from 1 to 25 nm, and

the third layer is a silicon oxide film having a geometrical film thickness of from 80 to 130 nm.

12. A substrate provided with antireflection films, which comprises a transparent substrate and first, second and third antireflection film layers deposited in this order on one side of the transparent substrate,

wherein the first layer is a titanium oxide film having a geometrical film thickness of from 1 to 25 nm,

the second layer is a tin oxynitride film having a geometrical film thickness of from 70 to 130 nm, and

the third layer is a silicon oxide film having a geometrical film thickness of from 80 to 130 nm.