A process for the modification of a surface of a solid material, comprising the step of contacting the surface with a surface-modifying composition under irradiation with light of a wavelength in the range of 200 to 800 nm optionally in the presence of a photoinitiator, wherein the solid material has surface groups selected from C-OH, Si-OH, C=O and C-O-C groups and wherein the surface-modifying composition comprises at least a hydrosilane and at least one reactive compound (A) other than the hydrosilane, wherein the reactive compound (A) comprises at least two functional groups selected from (meth)acrylate, (meth)acrylamide, hydroxyl, carboxylic acid, alkene, alkyne and epoxy, wherein the amount of hydrosilane in the composition ranges between 0.5 and 99 vol%, the amount of reactive compound (A) ranges between 1 and 50 vol%, wherein the amount of hydrosilane and reactive compound (A) are together between 10-100 vol% of the surface modifying composition and wherein the vol% is determined at 20 °C relative to the total of the surface modifying composition and wherein the hydrosilane is represented by any of the hydrosilanes according to formula I), II) or III), wherein R c = H or methyl, wherein R a is H, optionally substituted C 1-30 alkyl, optionally substituted C 2-30 alkenyl, optionally substituted C 2-30 alkynyl, optionally substituted C 6-20 aralkyl, optionally substituted C 6-10 aryl, or a polymeric moiety having a molecular weight of about 1000 to about 100,000, wherein each of R b and X is, independently, optionally substituted C 1-30 alkyl, optionally substituted C 2-30 alkenyl, optionally substituted C 2-30 alkynyl, optionally substituted C 6-20 aralkyl, optionally substituted C 6-10 aryl, or a polymeric moiety having a number average molecular weight of about 1000 to about 100,000, wherein the polymeric moiety is selected from the group consisting of hydrocarbon polymers, polyesters, polyamides, polyethers, polyacrylates, polyurethanes, epoxides, polymethacrylates and polysiloxanes (e.g. poly(methylhydrosiloxane)), wherein I = 2-10, preferably 2-4 and k = 3-6, preferably 3-4. wherein the reactive compound (A) comprises at least two functional groups selected from (meth)acrylate, (meth)acrylamide, hydroxyl, carboxylic acid, alkene, alkyne and epoxy, wherein the amount of hydrosilane in the composition ranges between 0.5 and 99 vol%, the amount of reactive compound (A) ranges between 1 and 50 vol%, wherein the amount of hydrosilane and reactive compound (A) are together between 10-100 vol% of the surface modifying composition and wherein the vol% is determined at 20 °C relative to the total of the surface modifying composition and wherein the hydrosilane is represented by any of the hydrosilanes according to formula I), II) or III), wherein R c = H or methyl, wherein R a is H, optionally substituted C 1-30 alkyl, optionally substituted C 2-30 alkenyl, optionally substituted C 2-30 alkynyl, optionally substituted C 6-20 aralkyl, optionally substituted C 6-10 aryl, or a polymeric moiety having a molecular weight of about 1000 to about 100,000, wherein each of R b and X is, independently, optionally substituted C 1-30 alkyl, optionally substituted C 2-30 alkenyl, optionally substituted C 2-30 alkynyl, optionally substituted C 6-20 aralkyl, optionally substituted C 6-10 aryl, or a polymeric moiety having a number average molecular weight of about 1000 to about 100,000, wherein the polymeric moiety is selected from the group consisting of hydrocarbon polymers, polyesters, polyamides, polyethers, polyacrylates, polyurethanes, epoxides, polymethacrylates and polysiloxanes (e.g. poly(methylhydrosiloxane)), wherein I = 2-10, preferably 2-4 and k = 3-6, preferably 3-4. <EOS>