An antifogging agent composition which contains a
copolymer (A),
colloidal silica (B) and a
solvent (C), wherein: (A) is a (
meth)
acrylate copolymer obtained from a
monomer mixture which contains monomers (a-1) to (a-3); (C) contains water (C-1), a C1-4 monovalent
alcohol-based
solvent (C-2), a
solvent (C-3) which has one or more functional groups per molecule which are selected from the group consisting of a
ketone group, an ester group, two or more
ether groups, a
thioketone group and an
amide group, and has a
boiling point of 100-200°C, inclusive, and a glycol
ether-based solvent (C-4) which is represented by general formula (5) (R10-O-R11-OH); and the combined total of (C-1) to (C-4) relative to 100 parts by
mass of the combined total of (A) and (B), and the
mass ratios of (C-3) and (C-4) relative thereto, are specific amounts. Said antifogging agent composition makes it possible to form an antifogging
coating which exhibits excellent transparency,
water resistance, initial adhesiveness, antifogging properties, and repeated antifogging properties, is unlikely to have water droplet marks left thereon, and also suppresses the formation of liquid droplets when applying the
coating, is
adhesive after pre-
drying when applying a thin film of the
coating, and suppresses the formation of cracks when applying a thick film thereof.