CONCAVO-CONVEX BUILDING BLOCK

PROBLEM TO BE SOLVED: To provide concavo-convex building blocks which hardly unpile even when they are piled up high and with which even an infant can play by easily assembling concave and convex parts, while infants had difficulty in piling up conventional blocks high because they slip. SOLUTION: A concave surface or a convex surface is arranged on each of the whole surfaces of the building block. The convex and concave surfaces have printed patterns and plain faces mixed thereon. The concave-convex building blocks can be enjoyed by freely assembling the convex and concave surfaces or combining patterns. COPYRIGHT: (C)2011,JPO&INPIT