Patent ID: 6685323
Filing Date: 2004-02-03
Classification: G02B,G09F

Abstract:
A triangular-pyramidal cube-corner retroreflective sheeting characterized in that triangular-pyramidal cube-corner retroreflective elements protruded beyond a first common bottom plane (virtual plane X-Xâ€²) are arranged so as to be faced each other in the closest-packed state on the first bottom plane (virtual plane X-Xâ€²) by sharing each base edge on the first bottom plane (virtual plane X-Xâ€²), the first bottom plane (virtual plane X-Xâ€²) is a common plane including the base edges (x, x, . . . ) shared by the triangular-pyramidal reflective elements, two opposite triangular-pyramidal reflective elements form a substantially-same-shape element pair faced each other so as to be substantially symmetric to planes (Y-Yâ€², Y-Yâ€², . . . ) vertical to the first bottom plane including the shared base edges (x, x, . . . ) on the first bottom plane (virtual plane X-Xâ€²), the triangular-pyramidal reflective elements are formed by substantially same triangular lateral faces (faces c1 and c2) using each of the shared base edges (x, x, . . . ) as one side and two substantially same quadrangular lateral faces (faces a1 and b1 or faces a2 or b2) substantially perpendicularly crossing the lateral faces (faces c1 and c2), which (the above lateral faces a1 and b1 or lateral faces a2 or b2) use each of two upper sides of the triangular lateral faces (faces c1 and c2) started from apexes (H1 and H2) of the triangular-pyramidal reflective elements as one side and share one ridge line of the triangular-pyramidal reflective elements as one side, and the height (hâ€²) from the apexes (H1 and H2) of the triangular-pyramidal reflective elements up to the first bottom plane (virtual plane X-Xâ€²) including the base edges (x, x, . . . ) of the triangular lateral faces (faces c1 and c2) of the triangular-pyramidal reflective elements is substantially smaller than the height (h) from the apexes (H1 and H2) of the triangular-pyramidal reflective elements up to a substantially-horizontal second bottom plane (Z-Zâ€²) including base edges (z and w) of other lateral faces (faces a1 and b1 or faces a2 or b2) of the triangular-pyramidal reflective elements.