Abstract: Provided is a surface treatment agent capable of imparting superior antifouling property as well as good and durable hydrophilicity to an inorganic substrate. The surface treatment agent is one comprising a pretreatment agent and a hydrophilizing treatment agent and being to be sequentially applied to an inorganic substrate, wherein the pretreatment agent comprises a silane compound having a reactive silyl group and an organic functional group and a polyfunctional monomer, and the polyfunctional monomer has one or more first reactive groups that react with the organic functional group and one or more second reactive groups that react with the hydrophilizing treatment agent.

Abstract: Provided is a hydrophilic treatment coating composition which imparts a soil guard property and is superior in durability of soil guard performance. Provided is a hydrophilic treatment coating composition for an inorganic substrate surface-treated with a silane coupling agent (S), comprising a hydrophilic compound (A) and a hydrophilic compound (B), wherein the hydrophilic compound (A) is a compound having at least one of a sulfonic acid group and an alkali metal salt of a sulfonic acid group, and the hydrophilic compound (B) is a compound having a quaternary ammonium cationic group.

Abstract: Provided is a means for imparting hydrophilicity to a surface of a sanitary facility by means other than hydrophilic particles. A sanitary facility having a hydrophilized organic surface, wherein the hydrophilized organic surface has at least an organic cationic group, and a zeta potential at pH=7 of the hydrophilized organic surface is more than ?40 mV.