Inorganic hydrophilic coating solution, hydrophilic coating film obtained therefrom, and member using same

An inorganic hydrophilic coating solution comprising:

• (a) an aqueous solution comprising water and an amorphous silicate compound obtained by hydrolyzing and condensing a tetrafunctional silicon compound having a purity of 99.0 mass% or greater in an aqueous medium in the presence of an organic ammonium salt represented by structural formula (2) shown below:
• R24N+X− (2)
• wherein R2 is independently at each instance selected from the group consisting of methyl, ethyl, propyl, isopropyl and butyl, and X represents a hydroxyl group (OH), and an amount added of the organic ammonium salt in the hydrolysis and condensation is 100 mol % to 500 mol % relative to the amount of the tetrafunctional silicon compound, at a temperature within a range from 10 to 170° C.,
• wherein the tetrafunctional silicon compound is:
• an amorphous silica having an SiO2 content of 99.0 mass % or greater, a content of each of Na2O, K2O, Fe2O3, CaO, SO3, MgO, and P2O5 of 0.1 mass% or less, and a primary particle size of 500 nm or less, or
• tetraethyl orthosilicate;
• and
• (b) optionally, not more than 30 mass % of an alcohol, a ketone, a surfactant, or a mixture of two or more thereof, wherein
• a concentration of a solid fraction derived from the aqueous solution comprising the amorphous silicate compound is 0.01 to 2.0 mass %, and a pH is 5 to 8,
• wherein in a spectrum obtained by performing a 29Si-NMR measurement of the aqueous solution comprising the amorphous silicate compound, when a surface area ratio of a peak attributable to a Qn structure, wherein n of Qn is an integer of 0 to 4, relative to all peaks is used to calculate a molar ratio Rn, wherein Q0 is an uncondensed silicate monomer, Q1 is a monocondensate of a silicate monomer, Q2 is a dicondensate of a silicate monomer, Q3 is a tricondensate of a silicate monomer, and Q4 is a tetracondensate of a silicate monomer, and Rn, wherein n of Rn is an integer of 0 to 4, is a molar ratio of silicon atoms within the Qn structure relative to all silicon atoms within the aqueous solution comprising the amorphous silicate compound, then the relationships shown below are satisfied:
• (R0+R1+R2+R3)≥90 mol %, R3≥40 mol %, and R4≤5 mol %.