Modified sheet-like inorganic compound, and resin composition containing same

The present invention addresses the problem of providing: a modified sheet-like inorganic compound which is produced by a surface treatment with a phosphonic acid or phosphoric acid derivative that enables the provision of a water vapor barrier material having high water vapor barrier performance and adhesiveness and also having excellent transparency; and a resin composition containing the modified sheet-like inorganic compound. The problem can be solved by treating the surface of a sheet-like inorganic compound with a phosphonic acid or phosphoric acid derivative substituted by a group selected from a linear alkyl or alkenyl group having 4 to 30 carbon atoms, a hydroxy group, an alkoxy group, a linear alkyl or alkenyl group which has 1 to 30 carbon atoms and may have an aromatic group, an aromatic group, and a cyclic alkyl or alkenyl group which has 4 to 30 carbon atoms and may have a hydroxy group, an alkoxy group or an aromatic group.