Nippon Carbide Industries Co., Inc.

Nippon Carbide Kogyo Kabushiki Kaisha

Keiji Amemiya

Ikuo Mimura

Chihiro Hayashi

Mitsugu Shozen

A hexagonal cube corner retroreflective article has a set of a large number of hexagonal cube corner retroreflective elements. In the retroreflective element, at least one reflective lateral face (face a, face b, and/or, face c) is divided into a pair of an upper secondary reflective lateral face (face aface band/or face c) and a lower secondary reflective lateral face (face aface band/or face c) partitioned by a line segment (EF, FD, and/or DE) connected by apexes (E, F, and/or D) constituting that reflective lateral face, in which two secondary reflective lateral faces constituting the pair of the secondary reflective lateral faces are not on the same plane. By these features the retroreflective article provides excellent observational angle characteristics.

Hexagonal cube corner retroreflective article

A retroreflective article having excellent retroreflective efficiency, entrance angle characteristic, observation angle characteristic, and rotation angle characteristic is provided. In a retroreflective article including a number of cube corner retroreflective elements formed in a closely packed manner on a common plane (plane Sc), each of the cube corner retroreflective elements having three reflective lateral surfaces (surface a, surface b and surface c) that have three edge lines (HD, HE and HF) and one apex (H) in common and an optical axis that passes through the apex (H) and is at equal distance from the three reflective lateral surfaces (surface a, surface b and surface c), the retroreflective article includes at least two or more types of cube corner retroreflective elements having optical axes tilted with respect to each other within a plane (plane Sv) that is perpendicular to a reflective lateral surface (surface c) and includes a common edge line (HF) of the other reflective lateral surfaces (surface a and surface b) and a perpendicular line from the apex (H) to the common plane (plane Sc).

Retroreflective article

The present invention relates to a triangular pyramidal cube corner retroreflective article and a producing method thereof. In the triangular pyramidal cube corner retroreflective article, a triangular pyramidal cube corner retroreflective element pair group is disposed in a closest-packed fashion on a common plane defined by three base lines, and the each of retroreflective elements in a pair having one base line (A-B) shared by the retroreflective elements in the pair. The triangular pyramidal cube corner retroreflective article includes a first element pair group, in which two interior angles (&#x3b1;=&#x2220;BAC and &#x3b2;=&#x2220;ABC) formed by the shared base line of the element pair and two other base lines are different from each other and the element pair is line-symmetrically disposed in relation to the shared base line (A-B); and a second element pair group, in which the element pair is congruent to a line-symmetrical shape to the first element pair in relation to a line segment connecting vertexes of the base planes.

Triangular pyramid type cube corner retroreflection article, and its manufacturing method

A cube-corner retroreflective article is provided with a number of cube-corner retroreflective element pairs each formed by a pair of cube-corner retroreflective elements sharing one side. Each of the cube-corner retroreflective elements has reflective lateral surfaces including two trapezoidal reflective lateral surfaces and one pentagonal or isosceles-triangular reflective lateral surface, and a projection shape of a quadrangle when projected onto a common plane, wherein ratios (rHA/rHC and rHB/rHC) between a length (rHC) of a ridge (HC) shared by the trapezoidal reflective lateral surfaces (HAFC and HBGC) and lengths (rHA and rHB) of other ridges (HA and HB) are in a range of 0.5 to 1.5.

Growing community of inventors

Namerikawa, Japan

Keiji Amemiya