A dermal therapeutic system which comprises an adhesive polymeric matrix comprising - an acrylate-vinyl acetate copolymer having a Tg below 0°C, preferably self-curing, which contains free hydroxyl groups without free carboxyl groups, said acrylate-vinyl acetate copolymer being present in a percentage ranging from 45 to 650 by weight with respect to the total dry weight of the adhesive polymeric matrix, said acrylate-vinyl acetate copolymer being obtained from variable percentages of two or more monomers selected from a group comprising - 2-ethylhexyl-acrylate - 2-methyl-acrylate - 2-hydroxyethyl-acrylate - 2-oxyranylmethyl-methacrylate - 1-butanol titanium salt and - ethenyl acetate or vinyl acetate; and a basic butylated methacrylate copolymer, said methacrylate copolymer being present in a percentage ranging from 5 to 20% by weight with respect to the total dry weight of the adhesive polymeric matrix, as adhesive components, - an organic acid which is citric acid monohydrate or an inorganic acid which is hydrochloric acid, in a percentage ranging from 0.5 to 3.5% by weight with respect to the total dry weight of the adhesive polymeric matrix, as stabilizer, - a salt of Diclofenac in a percentage ranging from 8 to 20% by weight with respect to the total dry weight of the adhesive polymeric matrix, as active principle, - the complement to 100 % by weight with respect to the total dry weight of the adhesive polymeric matrix, consisting of excipients and/or pharmaceutically acceptable additives, such as, for example, adhesion modulators. - an acrylate-vinyl acetate copolymer having a Tg below 0°C, preferably self-curing, which contains free hydroxyl groups without free carboxyl groups, said acrylate-vinyl acetate copolymer being present in a percentage ranging from 45 to 650 by weight with respect to the total dry weight of the adhesive polymeric matrix, said acrylate-vinyl acetate copolymer being obtained from variable percentages of two or more monomers selected from a group comprising - 2-ethylhexyl-acrylate - 2-methyl-acrylate - 2-hydroxyethyl-acrylate - 2-oxyranylmethyl-methacrylate - 1-butanol titanium salt and - ethenyl acetate or vinyl acetate; and a basic butylated methacrylate copolymer, said methacrylate copolymer being present in a percentage ranging from 5 to 20% by weight with respect to the total dry weight of the adhesive polymeric matrix, as adhesive components, - 2-ethylhexyl-acrylate - 2-methyl-acrylate - 2-hydroxyethyl-acrylate - 2-oxyranylmethyl-methacrylate - 1-butanol titanium salt and - ethenyl acetate or vinyl acetate; and - an organic acid which is citric acid monohydrate or an inorganic acid which is hydrochloric acid, in a percentage ranging from 0.5 to 3.5% by weight with respect to the total dry weight of the adhesive polymeric matrix, as stabilizer, - a salt of Diclofenac in a percentage ranging from 8 to 20% by weight with respect to the total dry weight of the adhesive polymeric matrix, as active principle, - the complement to 100 % by weight with respect to the total dry weight of the adhesive polymeric matrix, consisting of excipients and/or pharmaceutically acceptable additives, such as, for example, adhesion modulators. <EOS>