Optical article having an interferential coating with an improved abrasion-resistance

Patent metadata

Field	Value
Publication number	US-12092908-B2
Application number	US-201917285591-A
Country	US
Kind code	B2
Filing date	Oct 17, 2019
Priority date	Oct 18, 2018
Publication date	Sep 17, 2024
Grant date	Sep 17, 2024

Abstract

The invention relates to an optical article comprising a substrate having at least one main face successively coated with a layer comprising chromium, silicon and oxygen, a monolayer sub-layer having a thickness higher than or equal to 100 nm, a multilayer interferential coating comprising a stack of at least one high refractive index layer having a refractive index higher than 1.55 and at least one low refractive index layer having a refractive index of 1.55 or less, wherein the ratio (I) is higher than or equal to 1.5, and the optical article has a Bayer value determined in accordance with the ASTM F735-81 standard higher than or equal to 7.

R
D

=

thickness
⁢

⁢
of
⁢

⁢
the
⁢

⁢
outermost
⁢

⁢
low
⁢

⁢
refractive
⁢

⁢
index

layer
⁡

(
s
)

⁢

⁢
of
⁢

⁢
the
⁢

⁢
interferential
⁢

⁢
coating

thickness
⁢

⁢
of
⁢

⁢
the
⁢

⁢
outermost
⁢

⁢
high
⁢

⁢
refractive
⁢

⁢
index

layer
⁡

(
s
)

⁢

⁢
of
⁢

⁢
the
⁢

⁢
interferential
⁢

⁢
coating

(
I
)

First claim

The invention claimed is:

1. An optical article comprising a substrate having at least one main face successively coated with:
a layer comprising chromium, silicon and oxygen;
a monolayer sub-layer having a thickness higher than or equal to 100 nm;
a multilayer interferential coating comprising a stack of at least one high refractive index layer having a refractive index higher than 1.55 and at least one low refractive index layer having a refractive index of 1.55 or less, wherein the ratio:

R
D

=

thickness
⁢

⁢
of
⁢

⁢
the
⁢

⁢
outermost
⁢

⁢
low
⁢

⁢
refractive
⁢

⁢
index

layer
⁡

(
s
)

⁢

⁢
of
⁢

⁢
the
⁢

⁢
interferential
⁢

⁢
coating

thickness
⁢

⁢
of
⁢

⁢
the
⁢

⁢
outermost
⁢

⁢
high
⁢

⁢
refractive
⁢

⁢
index

layer
⁡

(
s
)

⁢

⁢
of
⁢

⁢
the
⁢

⁢
interferential
⁢

⁢
coating

is higher than or equal to 1.7; and
wherein the optical article has a Bayer value determined in accordance with the ASTM F735-81 standard higher than or equal to 7.

2. The optical article claim 1 , wherein the sub-layer has a thickness higher than or equal to 120 nm.

3. The optical article claim 1 , wherein the sub-layer has a thickness higher than or equal to 130 nm.

4. The optical article claim 1 , wherein the sub-layer is a SiO 2 -based layer.

5. The optical article claim 1 , wherein the sub-layer is in direct contact with the interferential coating.

6. The optical article claim 1 , wherein the sub-layer is under compression with a compressive stress lower than −250 MPa.

7. The optical article claim 1 , wherein the layer comprising chromium, silicon and oxygen has a thickness lower than or equal to 10 nm.

8. The optical article claim 1 , wherein the layer comprising chromium, silicon and oxygen has a refractive index higher than 1.55.

9. The optical article claim 1 , wherein the layer comprising chromium, silicon and oxygen is in direct contact with the sub-layer.

10. The optical article claim 1 , wherein the deposition of the sub-layer is conducted in a vacuum chamber under a pressure lower than 1.6×10 −4 mBar.

11. The optical article claim 1 , wherein the deposition of the sub-layer is conducted in a vacuum chamber in which no supplementary gas is supplied during said deposition.

12. The optical article claim 1 , wherein the interferential coating is an antireflection coating.

13. The optical article claim 1 , wherein the optical article is an ophthalmic lens.

14. A method of manufacturing the optical article of claim 1 , comprising:
providing an optical article comprising a substrate having at least one main face;
depositing onto a main surface of the substrate a layer comprising chromium, silicon and oxygen;
depositing a monolayer sub-layer having an exposed surface and a thickness higher than or equal to 100 nm onto said layer comprising chromium, silicon and oxygen;
depositing onto said exposed surface of the sub-layer a multilayer interferential coating comprising at least one high refractive index layer having a refractive index higher than 1.55 and at least one low refractive index layer having a refractive index of

Assignees

• Essilor Int

Inventors

• Emprin Benoit
• Maitre Nicolas
• Chiarotto Sébastien

Classifications

• B32B7/023

  Optical properties · CPC title

• G02C7/024

  Methods of designing ophthalmic lenses · CPC title

• G02C7/022

  Ophthalmic lenses having special refractive features achieved by special materials or material structures (G02C7/049 takes precedence) · CPC title

• G02B1/115 Primary

  Multilayers · CPC title

• C23C14/081

  of aluminium, magnesium or beryllium · CPC title