摘要 |
The present invention relates to a triangular-pyramidal cube-corner retroreflective sheet constituted with triangular-pyramidal cube-corner retroreflective elements useful for signs including traffic signs and construction work signs, license plates of automobiles and motorcycles, safety materials of clothing and life preservers, markings of signboards, and reflectors of visible-light, laser-beam, and infrared-ray reflective sensors, in which a lateral face (c) using one of the base edge (x) of triangular-pyramidal reflective elements arranged in a close-packed state on a base plane (X-X') and facing each other by sharing the base edge (x) on the base plane (X-X') as one side is pentagonal, other faces (a, b) sharing one of ridge lines starting with apex (H) of the triangular-pyramidal reflective elements are quadrangular, and the height (h) from the apex (H) up to the base plane (X-X') is substantially larger than the height (h') from the apex (H) up to a substantially horizontal plane (virtual plane Z-Z') including the base edges (z, w) of other lateral faces (a, b) of the triangular-pyramidal reflective elements. |