Composition

A composition comprising

• [1] a polymer constituting a water-repellent component, the polymer containing
• a constituent unit derived from
• (A) at least one modified fine particle containing
• (i) a core fine particle and
• (ii) one or more modifying moieties that modify the core fine particle, wherein some or all of the one or more modifying moieties have one or more polymerizable groups (a), and
• a constituent unit derived from
• (Bs) at least one compound containing one or more polymerizable groups (b) in the molecule, and containing fluorine;
• [2] a monomer (Bm) constituting an abrasion-resistant component;
• and
• [3] a solvent mainly containing one or more solvents selected from the group consisting of non-fluorine organic solvents and water,
• wherein
• the ratio of the mass of the abrasion-resistant component [2] to the total mass of the water-repellent component [1] and the abrasion-resistant component [2] is 85:100 to 35:100.

A method for producing a coating film, the method comprising

• (1) a step of allowing one or more compounds (Bs) to bind to modified fine particle (A) to obtain fine particle (Ab) having at least one polymerizable group (a);
• (2) a step of applying a composition containing fine particle (Ab) obtained in the step (1) and compound (Bm) for constituting an abrasion-resistant component to a surface to be treated;
• and
• (3) a step of polymerizing compound (Bm) on the surface to be treated.

A method for producing a fluorine-containing water-repellent component comprising

• a constituent unit derived from
• (A) at least one modified fine particle containing
• (i) a core fine particle and
• (ii) one or more modifying moieties that modify the core fine particle, wherein some or all of the one or more modifying moieties have one or more polymerizable groups (a);
• and a constituent unit derived from
• (B) at least one compound containing one or more polymerizable groups (b) in the molecule, and containing fluorine,
• the method comprising
• reacting the modified fine particle (A) with the at least one compound (B) in a non-fluorine organic solvent.