Laminated film and method for producing same

A laminated film comprising a polyester film having a resin layer on at least one side thereof,

• wherein said resin layer contains at least
• metal oxide particles (A) having a number average particle diameter of 3 nm or more and 50 nm or less, and
• an acrylic resin (B), and
• a component (C1) derived from an oxazoline-based compound and/or a component (C2) derived from a melamine-based compound, and
• wherein said acrylic resin (B) contains a monomer unit (b1) represented by Formula (1), a monomer unit (b2) represented by Formula (2), and a monomer unit (b3) represented by Formula (3):
• (wherein in Formula (1), R1 group represents a hydrogen atom or a methyl group;
• and n represents an integer of 9 or more and 34 or less)
• (wherein in Formula (2), R2 group represents a hydrogen atom or a methyl group;
• and R4 group represents a group containing 2 or more saturated hydrocarbon ring)
• (wherein in Formula (3), R3 group represents a hydrogen atom or a methyl group;
• and R5 group represents a hydroxyl group, a carboxyl group, a tertiary amino group, a quaternary ammonium salt group, a sulfonate group, or a phosphate group).

A method for producing a laminated film comprising forming a resin layer(s) on at least one side of a polyester film, wherein said method comprises:

• forming a resin on at least one side of the polyester film using the following resin composition;
• then stretching said laminated film at least uniaxially;
• and then subjecting said laminated film to heat treatment,
• wherein said resin composition contains at least
• metal oxide particles (A) having a number average particle diameter of 3 nm or more and 50 nm or less, and
• an acrylic resin (B), and
• an oxazoline-based compound (C1′) and/or a melamine-based compound (C2′),
• wherein said acrylic resin (B) contains a monomer unit (b1) represented by Formula (1), a monomer unit (b2) represented by Formula (2), and a monomer unit (b3) represented by Formula (3):
• (wherein in Formula (1), R1 group represents a hydrogen atom or a methyl group;
• and n represents an integer of 9 or more and 34 or less)
• (wherein in Formula (2), R2 group represents a hydrogen atom or a methyl group;
• and R4 group represents a group containing 2 or more saturated hydrocarbon ring)
• (wherein in Formula (3), R3 group represents a hydrogen atom or a methyl group;
• and R5 group represents a hydroxyl group, a carboxyl group, a tertiary amino group, a quaternary ammonium salt group, a sulfonate group, or a phosphate group).