Patterned pavement markings with upright retroreflectors

A method of making a pavement marking sheet material comprising the steps of:

• 1) providing a continuous polymeric base sheet having a plurality of protuberances on its upper surface,
• said upper surface being made up of a plurality of segments arranged in a selected manner,
• each said segment having a front edge, rear edge, and two side edges, and having one protuberance or an array of a plurality of said protuberances positioned along said front edge and a spacing zone that is free of said protuberance or array of a plurality of protuberances along said rear edge such that said protuberance or array of a plurality of protuberances are positioned closer to said front edge than to said rear edge, the longitudinal length L of said spacing zone being greater than H/tan(90.degree.-.theta.), where H is the height of said protuberance or array of a plurality of protuberances and .theta. is a design entrance angle that falls within the range of 86.9.degree. to 8.9.6.degree.;
• 2) applying a fluid coating to each protuberance;
• 3) depositing coated microspheres onto the fluid coating and allowing the microspheres to become partially embedded in the coating;
• and
• 4) solidifying said fluid coating.