Claims
- 1. A retroreflective article comprising a transparent base sheet having first and second broad faces, said second face being substantially planar and said first face having an array of substantially hemi-spheroidal microlenses thereon, said microlenses being wider and shorter than portions of true spheres, the shape of said microlenses and thickness of said base sheet being such that collimated light substantially orthogonally incident to said array is focused approximately at said second face, wherein said second face has a nacreous pigment coating thereon.
- 2. The article of claim 1 further comprising an imaging material disposed between said second face of said base sheet and said nacreous pigment coating.
- 3. The article of claim 2 wherein said imaging material comprises a second nacreous pigment coating.
- 4. The article of claim 3 wherein said first and second nacreous pigment coatings have distinctly different colors under ordinary diffuse lighting conditions.
- 5. The article of claim 1 wherein said nacreous pigment coating comprises nacreous pigment particles, a binder resin, and a dye.
- 6. The article of claim 5 wherein said dye has a color which is dark enough relative to the color of said nacreous pigment particles that said dye masks the color of said nacreous pigment particles under ordinary diffuse lighting conditions but does not mask the color of said nacreous pigment particles under retroreflective viewing conditions.
- 7. The article of claim 1 wherein said nacreous pigment coating is discontinuous.
- 8. The article of claim 7 wherein said nacreous pigment coating forms a pattern on said second face.
- 9. The article of claim 7 wherein a reflective layer is disposed over said nacreous pigment coating.
- 10. The article of claim 9 wherein said reflective layer is opaque and discontinuous.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of application Ser. No. 07/613,136 filed Nov. 15, 1990, now U.S. Pat. No. 5,254,390.
US Referenced Citations (32)
Foreign Referenced Citations (2)
Number |
Date |
Country |
1303103 |
Jan 1973 |
GBX |
WO9208998 |
May 1992 |
WOX |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
613136 |
Nov 1990 |
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