Compound fine particles and composition for forming film

A compound fine particle dispersion which comprises:

• compound fine particles and
• a dispersion medium;
• wherein said compound fine particles include:
• inorganic fine particles comprising silica;
• an organic polymer bound to surfaces of said inorganic fine particles, said organic polymer comprising a (meth)acrylic monomer unit and is formable into a film;
• and
• wherein said compound fine particles comprise at least one kind of alkoxy group in a proportion of 0.01 to 50 mmol/g, have an inorganic matter content of 50 to 99.5% by weight and have an average particle diameter of 5 to 200 nm and a particle diameter variation coefficient of 50% or less.

A compound fine particle dispersion which comprises:

• compound fine particles and
• a dispersion medium;
• wherein said compound fine particles are obtained by a process including a step of hydrolyzing and condensing an organic polymer (p) in the presence of a basic catalyst,
• wherein said organic polymer (P) has at least one polysiloxane group per molecule, and
• wherein said polysiloxane group contains at least one Si--OR.sup.1 group, wherein R.sup.1 denotes a hydrogen atom or at least one member selected from the group consisting of alkyl groups, acyl groups, substituted alkyl groups and substituted acyl groups;
• with the proviso that in the case where plural R.sup.1 are included in one molecule of said polymer (P), the plural R.sup.1 may be different from each other.

Compound fine particles comprising:

• inorganic fine particles;
• an organic polymer bound to surfaces of said inorganic fine particles;
• and
• wherein the compound fine particles have an average particle diameter of 5 to 200 nm and a particle diameter variation coefficient of 50% or less;
• wherein said compound find particles are produced by the process comprising the steps of:
• hydrolyzing and condensing an organic polymer (P) in the presence of a basic catalyst,
• wherein said organic polymer (P) has at least one polysiloxane group per molecule, said polysiloxane group containing at least one Si--OR.sup.1 group, wherein R.sup.1 denotes a hydrogen atom or at least one member selected from the group consisting of alkyl groups, acyl groups, substituted alkyl groups and substituted acyl groups;
• with the proviso that in the case where plural R.sup.1 are included in one molecule of said polymer (P), the plural R.sup.1 may be different from each other.

A film-forming composition comprising a resin and a compound fine particle dispersion comprising:

• compound fine particles and
• a dispersion medium;
• wherein said compound fine particles including:
• inorganic fine particles;
• an organic polymer bound to surfaces of said inorganic fine particles;
• and
• wherein said compound fine particles having an average particle diameter of 5 to 200 nm and a particle diameter variation coefficient of 50% or less, and wherein said compound fine particles are obtained by hydrolyzing and condensing an organic polymer (P) in the presence of a basic catalyst.

A film-forming composition comprising a resin and a compound fine particle dispersion comprising:

• compound fine particles and
• a dispersion medium;
• wherein said compound fine particles are obtained by a process including a step of hydrolyzing and condensing an organic polymer (P) in the presence of a basic catalyst,
• wherein said organic polymer (P) has at least one polysiloxane group per molecule, and
• wherein said polysiloxane group contains at least one Si--OR.sup.1 group, wherein R.sup.1 denotes a hydrogen atom or at least one member selected from the group consisting of alkyl groups, acyl groups, substituted alkyl groups and substituted acyl groups;
• with the proviso that in the case where plural R.sup.1 are included in one molecule of said polymer (P), the plural R.sup.1 may be different from each other.