| abstract |
This surface treatment agent can form a water repellent/oil repellent layer having particularly excellent wear durability, weather resistance, and alkali resistance, and contains a fluorinated coating agent composition containing: (A) one or more selected from hydroxy group- or hydrolyzable group-containing silanes and siloxanes modified with a fluorooxyalkylene group-containing polymer, and partial (hydrolyzed) condensates thereof, and (B) a fluorooxyalkylene group-containing polymer-modified polysilazane formed of silazane units modified with a fluorooxyalkylene group-containing polymer, wherein the number-average molecular weight of fluorooxyalkylene group-containing polymer residues in the component (A) is 1,500-10,000, the number-average molecular weight of fluorooxyalkylene group-containing polymer residues in the silazane units modified with the fluorooxyalkylene group-containing polymer in the component (B) is 500-6,000, and the mixed mass ratio between the component (A) and the component (B) is 10:90 to 90:10. |