Retroreflective sheeting
The present application relates generally to retroreflective sheeting and the tools and methods used to make retroreflective sheeting. Microreplication tools and sheeting include controlled surface structure or haze. The surface structure or haze can be introduced, for example, by chemical etching of the tool surface and/or electroplating.
1. Retroreflective sheeting, comprising:
an array of cube corner elements wherein at an entrance angle of −4 degrees the sheeting exhibits a fractional retroreflectance slope of between about 3% and about 15% at an observation angle of about 0.5 degree.
2. The retroreflective sheeting of claim 1 , in which the cube corner elements are truncated cube corner elements.
3. The retroreflective sheeting of claim 1 , in which the fractional retroreflectance is between about 5% and about 12%.
4. The retroreflective sheeting of claim 1 , in which the cube corner elements have a lateral dimension of less than 0.020 inches.
5. The retroreflective sheeting of claim 1 and one or more of a sealing film and/or a smoothing film positioned adjacent to the retroreflective sheeting.
6. The retroreflective sheeting of claim 1 and a specular reflective coating positioned adjacent to the retroreflective sheeting.
7. The retroreflective sheeting of claim 1 , wherein the cube corner elements are canted.
8. The retroreflective sheeting of claim 1 , wherein the cube corner elements include a primary groove angle and a primary groove angle deviation from a design target of between about 0.05 degrees and about 0.2 degrees.
9. The retroreflective sheeting of claim 1 , wherein the cube corner elements are non-orthogonal.