Highly durable and abrasion-resistant dielectric coatings for lenses

• US 6,077,569 A
• Filed: 04/03/1998
• Issued: 06/20/2000
• Est. Priority Date: 03/03/1994
• Status: Expired due to Term

• Current Assignee: Morgan Advanced Ceramics Inc.
• Original Assignee: Diamonex, Inc. (Morgan Advanced Materials PLC)
• Inventors: Daniels, Brian Kenneth, Galvin, Norman Donald, Petrmichl, Rudolph Hugo, Kimock, Fred M., Knapp, Bradley J.
• Primary Examiner(s): PADGETT, MARIANNE L
• Application Number:
  US09/055,067
• Time in Patent Office: 809 Days
• Field of Search: 427/534, 427/563, 427/562, 427/577, 427/579, 427/527, 427/525, 427/530, 427/529, 427/566, 427/567, 427/564, 204/192.11, 204/192.16, 204/192.22, 204/192.23, 204/192.26, 204/192.3, 204/192.34, 204/192.36
• US Class Current: 427/534
• CPC Class Codes: B05D 1/62 Plasma-deposition of organic layers plasma deposition in general C23C14/00, C23C16/00
• CPC Class Codes: B29C 59/16 by wave energy or particle radiation , e.g. infrared heating B29C59/007 takes precedence
• CPC Class Codes: C08J 7/123 Treatment by wave energy or particle radiation C08J7/18 takes precedence
• CPC Class Codes: C23C 14/02 Pretreatment of the material to be coated C23C14/04 takes precedence
• CPC Class Codes: C23C 14/024 Deposition of sublayers, e.g. to promote adhesion of the coating C23C14/027 takes precedence
• CPC Class Codes: C23C 16/0245 by etching with a plasma
• CPC Class Codes: C23C 16/0272 Deposition of sub-layers, e.g. to promote the adhesion of the main coating
• CPC Class Codes: C23C 16/30 Deposition of compounds, mixtures or solid solutions, e.g. borides, carbides, nitrides
• CPC Class Codes: C23C 16/308 Oxynitrides
• CPC Class Codes: C23C 16/325 Silicon carbide
• CPC Class Codes: C23C 16/345 Silicon nitride
• CPC Class Codes: C23C 16/513 using plasma jets
• CPC Class Codes: G02B 1/105 Protective coatings
• CPC Class Codes: G02B 1/111 using layers comprising organic materials
• CPC Class Codes: G02B 1/14 Protective coatings, e.g. hard coatings
• CPC Class Codes: Y10T 428/263 Coating layer not in excess of 5 mils thick or equivalent
• CPC Class Codes: Y10T 428/31507 Of polycarbonate
• CPC Class Codes: Y10T 428/31551 Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
• CPC Class Codes: Y10T 428/31598 Next to silicon-containing [silicone, cement, etc.] layer
• CPC Class Codes: Y10T 428/31663 As siloxane, silicone or silane

Abstract

An abrasion-resistant dielectric composite product is described comprising a substrate and an abrasion wear resistant coating material comprising carbon, hydrogen, silicon, and oxygen and a dielectric material. An improved method is provided for the deposition of highly durable and abrasion-resistant multilayer dielectric antireflective coatings and reflective colored mirror coatings onto plastic lenses such as ophthalmic lenses, safety lenses, sunglass lenses, and sports optics. An adhesion-enhancing polymer layer may be deposited onto the plastic substrate prior to deposition of the abrasion-resistant first coating layer. The multilayer dielectric coating structure consists of a transparent, highly abrasion-resistant first coating, and a second dielectric coating composed of at least one layer of dielectric material. The abrasion-resistant first coating layer is deposited by ion-assisted plasma deposition from mixtures of organosiloxane or organosilazane precursor gases and oxygen, and has the properties of Nanoindentation hardness in the range of about 2 GPa to about 5 GPa, a strain to microcracking greater than about 1.5% and less than about 3.5%, a transparency greater than 85% throughout the visible spectrum, and an abrasion resistance greater than or equal to the abrasion resistance of glass. The preferred method for deposition of the abrasion-resistant first coating layer is plasma ion beam deposition using an organosiloxane precursor gas and oxygen. Optimum abrasion-resistance is obtained when the first coating layer thickness is in the range of about 5 microns to about 20 microns. The thickness, refractive index, and number of the dielectric layers in the second coating are chosen to produce the desired optical effects of either antireflection, or reflected color. Optimum environmental durability and abrasion-resistance is obtained by producing highly dense dielectric coatings by ion beam assisted electron beam evaporation, magnetron sputtering, ion beam assisted magnetron sputtering, ion beam sputtering, and ion-assisted plasma deposition, including plasma ion beam deposition, from precursor gases.

Claims

1. A method for depositing onto a plastic lens substrate an abrasion-resistant material and a dielectric material which comprises:

(a) chemically cleaning the surface of said substrate to remove contaminants;

(b) mounting said substrate in a deposition vacuum chamber and evacuating the air from said chamber;

(c) etching the surface of said substrate with a material selected from the group consisting of energetic ions, reactive species and mixtures thereof to further remove residual contaminants, and to activate the surface;

(d) plasma ion beam depositing using precursor gases onto the surface of said substrate an intermediate layer of said abrasion-resistant material consisting of carbon, hydrogen, silicon and oxygen by exposing said substrate to a deposition flux of carbon, hydrogen, silicon and oxygen and using a gridless ion source having a plasma chamber therein, wherein a plasma is generated in the plasma chamber and a gas stream containing at least a portion of said precursor gases is introduced outside of the ion source and into the plasma ion beam, and wherein said deposition flux is activated by said plasma and said substrate is bombarded by energetic ions during the deposition to coat said substrate;

(e) depositing onto the abrasion-resistant coated substrate at least one layer of said dielectric material by bombarding said coated substrate with energetic atoms or said energetic ions or other energetic ions;

(f) increasing the pressure in said vacuum chamber to atmospheric pressure; and

(g) recovering a product coated with said abrasion-resistant material having the properties of Nanoindentation hardness in a range of about 2 to about 5 GPa, a strain to microcracking greater than 1.5% and less than 3.5%, and an abrasion resistance greater than or equal to the abrasion resistance of plate glass, and said dielectric material.

2. The process of claim 1 wherein step (e) is carried out using ion beam sputtering.

3. The process of claim 1 wherein step (e) is carried out using magnetron sputtering.

4. The process of claim 1 wherein step (e) is carried out using ion beam assisted electron beam evaporation.

5. The process of claim 1 wherein step (e) is carried out using ion-assisted plasma deposition.

6. The process of claim 1 wherein step (e) is carried out using ion beam assisted magnetron sputtering.