Method for obtaining optical articles having superior abrasion resistant properties, and coated articles prepared according to such method

Abstract

A method for preparing an abrasion resistant optical article comprising: providing an optical article having at least one main face bearing an abrasion resistant coating; positioning said optical article in a vacuum deposition chamber; depositing a first inorganic layer comprising SiOonto and in direct contact with said abrasion resistant coating by vacuum evaporation of SiOand/or SiO, with 1<x<2, in said vacuum chamber, the thickness of said first inorganic layer ranging from 10 to 100 nm, wherein oxygen is introduced inside said vacuum chamber during said evaporation; said deposition being conducted without ion assistance; depositing a second inorganic layer comprising SiOonto and in direct contact with said first inorganic layer by vacuum evaporation of SiOand/or SiO, with 1<x<2, in said vacuum chamber, the thickness of said second inorganic layer ranging from 70 to 300 nm, wherein said deposition is conducted without ion assistance and the pressure in said vacuum chamber during the deposition of said second inorganic layer being lower than the pressure during evaporation of said first inorganic layer and optionally; applying onto and in direct contact with said second inorganic layer a hydrophilic or an antifouling hydrophobic layer, preferably having a thickness ranging from 1 to 15 nm, wherein the outermost layer of the article is said second inorganic layer, or, when present, said hydrophilic or hydrophobic layer.