Composite particles, composite particle dispersion composition, and method of preparing composite particle dispersion composition

A method of preparing a composite particle dispersion composition, comprising:

• (i) preparing a dispersion liquid which comprises (A) polymer particles comprising 2-70 wt % of a polymer phase (a) of the core and 98-30 wt % of a polymer phase (b) of the shell, wherein a functional group capable of forming a linkage group by reaction with a group shown by formula OR2 (R2 represents an alkyl group having 1-6 carbon atoms, an acyl group having 1-6 carbon atoms, or an aryl group having 6-10 carbon atoms) is bonded at least either on or near the surface of the polymer phase (b), and (B) a poor solvent for the polymer particles (A);
• (ii) preparing (C) a compound shown by the following formula (1);
• R1nM(OR2)z-n (1)
• wherein R1 represents a hydrogen atom or an organic group having 1-8 carbon atoms (excluding the group represented by OR2), R2 represents an alkyl group having 1-6 carbon atoms, an acyl group having 1-6 carbon atoms, or an aryl group having 6-10 carbon atoms, M represents Si or a metal atom with a valence of 3 or more, n is 0 or an integer of 1 or more, z is a valence of M, and z-n is an integer of 2 or more, provided that, when a plurality of R1s is present, each R1 may be the same or different, this also applies to R2;
• and
• (iii) polycondensing the compound (C) in the dispersion liquid.