ARTICLE COATED WITH AN INTERFERENCE COATING HAVING PROPERTIES THAT ARE STABLE OVER TIME
The invention relates to an article comprising a substrate having at least one main surface coated with a multilayer interference coating, said coating containing a layer A having a refractive index less than or equal to 1.55. The article is characterised in that: layer A forms either the outer interference coating layer or an intermediate layer that is in direct contact with the outer interference coating layer, said outer interference coating layer being a layer B having a refractive index less than or equal to 1.55; layer A is obtained by ion beam deposition of activated species from at least one compound C in gaseous form and containing in its structure at least one silicon atom, at least one carbon atom, at least one hydrogen atom and, optionally, at least one nitrogen atom and/or at least one oxygen atom, layer A being deposited in the presence of nitrogen and/or oxygen when compound A does not contain nitrogen and/or oxygen; and layer A is not formed from inorganic precursor compounds.
1 - 17 . (canceled)
18 . An article comprising a substrate having at least one main surface coated with a multilayer interference coating, said coating containing a layer A having a refractive index lower than or equal to 1.55, wherein:
said layer A is:
either the external layer of the interference coating;
or an intermediate layer, making direct contact with the external layer of the interference coating, this external layer of the interference coating being a layer B having a refractive index lower than or equal to 1.55;
and said layer A was obtained by deposition, under an ion beam, of activated species issued from at least one compound C in gaseous form, containing in its structure at least one silicon atom, at least one carbon atom, at least one hydrogen atom and, optionally, at least one nitrogen atom and/or at least one oxygen atom, the deposition of said layer A being carried out in the presence of nitrogen and/or oxygen when the compound A does not contain nitrogen and/or oxygen; and
said layer A is not formed from inorganic precursor compounds.
19 . The article of claim 18 , wherein the ion beam is emitted by an ion gun.
20 . The article of claim 18 , wherein the compound C contains at least one silicon atom bearing at least one alkyl group.
21 . The article of claim 18 , wherein the compound C contains at least one group of formula:
where R 1 to R 4 independently designate alkyl groups.
22 . The article of claim 18 , wherein the compound C is chosen from octamethylcyclotetrasiloxane and hexamethyldisiloxane.
23 . The article of claim 18 , wherein the silicon atom or atoms of the compound C contain no hydrolysable group.
24 . The article of claim 18 , wherein the layer A does not contain a separate metal oxide phase.
25 . The article of claim 18 , further defined as possessing a layer B deposited on the layer A, the layer B containing at least 50 wt % silica relative to the total weight of the layer B.
26 . The article of claim 25 , wherein the layer B contains at least 100 wt % silica relative to the total weight of the layer B.
27 . The article of claim 18 , wherein the layer A has a thickness ranging from 20 to 150 nm.
28 . The article of claim 27 , wherein the layer A has a thickness ranging from 25 to 120 nm.
29 . The article of claim 18 , wherein the layer B has a thickness ranging from 2 to 60 nm.
30 . The article of claim 29 , wherein the layer B has a thickness ranging from 5 to 50 nm.
31 . The article of claim 18 , wherein the interference coating contains low refractive index layers and all these low refractive index layers are inorganic in nature except for the layer A.
32 . The article of claim 18 , wherein all the layers of the interference coating are inorganic in nature, except for the layer A.
33 . The article of claim 18 , further defined as being an optical lens.
34 . The article of claim 18 , wherein the interference coating is an antireflection coating.
35 . The article of claim 18 , wherein the stress in the layer A ranges from 0 to -500 MPa.
36 . The article of claim 18 , wherein the stress in the interference coating ranges from 0 to −400 MPa.
37 . A process for manufacturing the article of claim 18 , comprising:
providing an article comprising a substrate having at least one main surface;
depositing, on said main surface of the substrate, a multilayer interference coating,
said coating containing a layer A having a refractive index lower than or equal to 1.55, which is:
either the external layer of the interference coating;
or an intermediate layer making direct contact with the external layer of the interference coating, this external layer of the interference coating being a layer B having a refractive index lower than or equal to 1.55;
recovering an article comprising a substrate having a main surface coated with said interference coating that contains said layer A, wherein said layer A was obtained by deposition, under an ion beam, of activated species issued from at least one compound C in gaseous form, containing in its structure at least one silicon atom, at least one carbon atom, at least one hydrogen atom and, optionally, at least one nitrogen atom and/or at least one oxygen atom, the deposition of said layer A being carried out in the presence of nitrogen and/or oxygen when the compound A does not contain nitrogen and/or oxygen, and in that the layer A is not formed from inorganic precursor compounds.