Inorganic filler, polyarylene sulfide resin composition, molded article, and methods for producing same

Provided are: a polyarylene sulfide resin composition that exhibits excellent mechanical strength and resistance to wet heat; a molded article thereof; an inorganic filler to be used in said composition; and methods for producing the same. More specifically, provided are: a polyarylene sulfide resin composition obtained by blending, relative to 100 parts by mass of a polyarylene sulfide resin, 1-100 parts by mass of an inorganic filler that has been surface treated with a sizing agent (alpha), which contains at least a urethane-modified epoxy resin that has an alkoxypolyoxyalkylene structure and a urethane resin that contains a sulfonate group, a sizing agent (beta), which contains a copolymer (beta1) that has a mass average molecular weight of 5000-150,000 and is obtained by radical copolymerization of a polymerizable monomer mixture comprising at least a (meth)acrylic acid ester and maleic acid (anhydride), or a sizing agent (gamma), which contains at least a polyether resin, a urethane resin and a silane c