A method for coating a substrate comprising the steps of: a) depositing on said substrate a polymerizable composition selected from one the following compositions: a composition consisting of: at least one epoxy monomer (i) and/or one silicone epoxy monomer (ii), and optionally at least one of: (iv) a radical photocatalyst, (v) a solvent possibly added with water surfactants in case the solvent is water; (vi) nanoparticles or microparticles made of metals, non-metals or metal or non-metal oxides, and organic particles; (vii) at least one of the following conventional additives: pigments, inorganic filler, organic and inorganic dyes, UV stabilizers, antioxidants; or a composition consisting of a least one silicone epoxy monomer (ii) and at least one monomer containing at least one ethylenic unsaturation (iii) and optionally at least one of: (iv) a radical photocatalyst, (v) a solvent possibly added with water surfactants in case the solvent is water; (vi) nanoparticles or microparticles made of metals, nonmetals or metal or non-metal oxides, and organic particles; (vii) at least one of the following conventional additives used in monomer composition: selected from pigments, inorganic filler, organic and inorganic dyes, UV stabilizers, antioxidants; b) polymerizing at a pressure ranging from 0.5 to 3 atm said polymerizable composition or by plasma treatment thereby obtaining a coating on said substrate, wherein said coating is free from ionic photocatalysts and has an amount of radical photocatalysts less than 5000 ppm, preferably less than 1000 ppm, more preferably less than 500 ppm, even more preferably less than 100 ppm. a) depositing on said substrate a polymerizable composition selected from one the following compositions: a composition consisting of: at least one epoxy monomer (i) and/or one silicone epoxy monomer (ii), and optionally at least one of: (iv) a radical photocatalyst, (v) a solvent possibly added with water surfactants in case the solvent is water; (vi) nanoparticles or microparticles made of metals, non-metals or metal or non-metal oxides, and organic particles; (vii) at least one of the following conventional additives: pigments, inorganic filler, organic and inorganic dyes, UV stabilizers, antioxidants; or a composition consisting of a least one silicone epoxy monomer (ii) and at least one monomer containing at least one ethylenic unsaturation (iii) and optionally at least one of: (iv) a radical photocatalyst, (v) a solvent possibly added with water surfactants in case the solvent is water; (vi) nanoparticles or microparticles made of metals, nonmetals or metal or non-metal oxides, and organic particles; (vii) at least one of the following conventional additives used in monomer composition: selected from pigments, inorganic filler, organic and inorganic dyes, UV stabilizers, antioxidants; a composition consisting of: at least one epoxy monomer (i) and/or one silicone epoxy monomer (ii), and optionally at least one of: (iv) a radical photocatalyst, (v) a solvent possibly added with water surfactants in case the solvent is water; (vi) nanoparticles or microparticles made of metals, non-metals or metal or non-metal oxides, and organic particles; (vii) at least one of the following conventional additives: pigments, inorganic filler, organic and inorganic dyes, UV stabilizers, antioxidants; or (iv) a radical photocatalyst, (v) a solvent possibly added with water surfactants in case the solvent is water; (vi) nanoparticles or microparticles made of metals, non-metals or metal or non-metal oxides, and organic particles; (vii) at least one of the following conventional additives: pigments, inorganic filler, organic and inorganic dyes, UV stabilizers, antioxidants; a composition consisting of a least one silicone epoxy monomer (ii) and at least one monomer containing at least one ethylenic unsaturation (iii) and optionally at least one of: (iv) a radical photocatalyst, (v) a solvent possibly added with water surfactants in case the solvent is water; (vi) nanoparticles or microparticles made of metals, nonmetals or metal or non-metal oxides, and organic particles; (vii) at least one of the following conventional additives used in monomer composition: selected from pigments, inorganic filler, organic and inorganic dyes, UV stabilizers, antioxidants; (iv) a radical photocatalyst, (v) a solvent possibly added with water surfactants in case the solvent is water; (vi) nanoparticles or microparticles made of metals, nonmetals or metal or non-metal oxides, and organic particles; (vii) at least one of the following conventional additives used in monomer composition: selected from pigments, inorganic filler, organic and inorganic dyes, UV stabilizers, antioxidants; b) polymerizing at a pressure ranging from 0.5 to 3 atm said polymerizable composition or by plasma treatment thereby obtaining a coating on said substrate,