A method for producing a patch comprising a support layer and an adhesive agent layer arranged on at least one surface of the support layer, the method comprising:step A) obtaining an adhesive agent layer composition comprising free ropinirole in an amount which results in a content of 5 to 13.2% by mass in an obtained adhesive agent layerstep B) heating the adhesive agent layer composition at a temperature in a range from 50 to 76°C for 5 minutes to 24 hours andstep C) cooling the heated adhesive agent layer composition to normal temperature at an average rate of temperature drop of 1 to 20 °C/hour, thereby obtaining the adhesive agent layer comprising the free ropinirole at a supersaturated concentration in a dissolved form.
