Reactive particles, the curable composition and the cured product containing the same

[PROBLEMS] To provide excellent cured product productivity and excellent hardness, scratch resistance, abrasion resistance, low curl, adhesion and chemical resistance on the surface of various substrates. In particular, the present invention provides reactive particles used in a resin composition capable of forming a coating film (cured film) having excellent chemical resistance, a resin composition containing the particles, and a cured product. (A) oxide particles of at least one element selected from the group consisting of silicon, aluminum, zirconium, titanium, zinc, germanium, indium, tin, antimony and cerium; A radical having a radically polymerizable unsaturated group and a hydrolyzable group; 1) an organic compound (b1) and at least one group selected from the group consisting of an oxetane group, a 3,4-epoxycyclohexyl group, and an epoxy group in the molecule, and a second compound having a hydrolyzable group. A reactive particle obtained by binding the organic compound (b2) of the above.