Patent ID: 7371339

Claim:
A method of forming retroreflective sheeting comprising the steps of: a) forming a first mold by forming a plurality of grooves in a body of mold material, the grooves intersecting at an angle to form an array of prisms formed into pairs of prisms, each prism comprising a base aperture and three intersecting lateral faces which meet at an apex, each of the lateral faces having a base edge which forms a portion of the perimeter of the base aperture and said base edge of each lateral face intersects the base edge of a contiguous lateral face to form a base point, wherein a first face of at least one prism in the array includes a first face first planar surface and a first face second planar surface, the first face first planar surface and the first face second planar surface being contiguous along an edge, the edge substantially parallel to the base edge of the first face, having a first end point and a second end point which forms at least a portion of a middle aperture, wherein the apex, the first end point, and a first base point are coplanar and form a continuous edge from the first base point to the apex; b) forming a second mold in the first mold, the second mold comprising a negative prism array pattern; c) forming said sheeting in said second mold; and d) removing the sheeting from the second mold.