A method for producing soft contact lenses, comprising the steps of: obtaining a plasma-treated silicone hydrogel contact lens which has a silicone hydrogel lens body and a plasma base coating thereon, wherein the silicone hydrogel lens body is essentially made of a silicone hydrogel material, wherein the plasma base coating has a thickness of from about 0.5 nm to about 40 nm; contacting the plasma-treated silicone hydrogel contact lens with a first aqueous coating solution including a poly(alkylacrylic acid)polymer at a coating temperature of from about 40°C to about 50°C for a contacting time of from about 60 minutes to about 300 minutes to form a soft contact lens precursor which is the plasma-treated silicone hydrogel contact lens additionally having a layer of poly(alkylacrylic acid)on top of the plasma base coating, wherein the first aqueous coating solution has a pH from 2.3 to 5.0 and the poly(alkylacrylic acid)polymer is a homopolymer or copolymer of methacrylic acid, ethyl acrylic acid or 2-(meth)acrylamidoglycolic acid, provided that the first aqueous coating solution includes one or more non-polymeric acids in a total amount for having an acid-induced change in elastic modulus, ΔE, of not greater than 15%, wherein Δ E = E i − E 0 E 0 × 100 % in which E i is the elastic modulus of the plasma-treated silicone hydrogel contact lens after being in contact with the first aqueous coating solution at the coating temperature for the contacting time and E o is the elastic modulus of the plasma-treated silicone hydrogel contact lens prior to contacting with the first aqueous coating solution; and heating the soft contact lens precursor obtained in step, in a second aqueous coating solution which comprises a water-soluble and thermally-crosslinkable hydrophilic polymeric material having azetidinium groups, at a temperature of from about 60°C to about 140°C for at least 30 minutes to crosslink the water-soluble thermally-crosslinkable hydrophilic polymeric material and the poly(alkylacrylic acid) polymer so as to form the soft contact lens with the composite coating thereon, wherein the composite coating comprise the plasma base coating and a hydrogel coating on top of the plasma base coating, wherein the soft contact lens in fully hydrated state has a friction rating of about 3 or lower after 7 cycles of manual rubbing test, the test is carried out as detailed in the description. obtaining a plasma-treated silicone hydrogel contact lens which has a silicone hydrogel lens body and a plasma base coating thereon, wherein the silicone hydrogel lens body is essentially made of a silicone hydrogel material, wherein the plasma base coating has a thickness of from about 0.5 nm to about 40 nm; contacting the plasma-treated silicone hydrogel contact lens with a first aqueous coating solution including a poly(alkylacrylic acid)polymer at a coating temperature of from about 40°C to about 50°C for a contacting time of from about 60 minutes to about 300 minutes to form a soft contact lens precursor which is the plasma-treated silicone hydrogel contact lens additionally having a layer of poly(alkylacrylic acid)on top of the plasma base coating, wherein the first aqueous coating solution has a pH from 2.3 to 5.0 and the poly(alkylacrylic acid)polymer is a homopolymer or copolymer of methacrylic acid, ethyl acrylic acid or 2-(meth)acrylamidoglycolic acid, provided that the first aqueous coating solution includes one or more non-polymeric acids in a total amount for having an acid-induced change in elastic modulus, ΔE, of not greater than 15%, wherein Δ E = E i − E 0 E 0 × 100 % in which E i is the elastic modulus of the plasma-treated silicone hydrogel contact lens after being in contact with the first aqueous coating solution at the coating temperature for the contacting time and E o is the elastic modulus of the plasma-treated silicone hydrogel contact lens prior to contacting with the first aqueous coating solution; and heating the soft contact lens precursor obtained in step, in a second aqueous coating solution which comprises a water-soluble and thermally-crosslinkable hydrophilic polymeric material having azetidinium groups, at a temperature of from about 60°C to about 140°C for at least 30 minutes to crosslink the water-soluble thermally-crosslinkable hydrophilic polymeric material and the poly(alkylacrylic acid) polymer so as to form the soft contact lens with the composite coating thereon, wherein the composite coating comprise the plasma base coating and a hydrogel coating on top of the plasma base coating, wherein the soft contact lens in fully hydrated state has a friction rating of about 3 or lower after 7 cycles of manual rubbing test, the test is carried out as detailed in the description.