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US4340273A Expired / Lapsed US ⏱️ 0.0 years remaining

Retro-reflecting sheet material

Assignee: Alcan Research and Development Ltd
•
Filing: 1980-10-27
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Granted: 1982-07-20
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Expires: 2000-10-27
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Abstract

Abstract The specification relates to retro-reflectors of the type used for road signs and markers and vehicle license plates to make these objects more noticeable to road users after dark. In the invention, the surface of a metal substrate is made retro-reflective by applying a layer of an organic polymeric material and adhering glass beads thereto, and then passing the substrate through a roller mill or the like with the glass beads covered by a platen so that the beads form indentations in the metal surface. The presence of the platen allows the pressing (indentation) step to take place without damage to the glass beads or to the layer between the beads and the metal surface. By this means, a hard metal article can be made directly retro-reflective.

Inventors

  • 👤 Stanton E. Jack
  • 👤 Robert O. Dark

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 18:15
CPC Classifications
B; B29; B29D; B29D11/00; B29D11/00605; B29D11/00615; G; G02; G02B; G02B5/00; G02B5/12; G02B5/126; G02B5/128

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 76 words
A retro-reflector comprising an indentable metal substrate, transparent material overlying a surface of the substrate, and a mono-layer of glass beads of high refractive index adhered to said transparent material and separated from said substrate by a layer of said transparent material, said surface of the substrate having indentations conforming to the adjacent glass beads and the separation of the glass beads from the substrate surface by said layer of transparent material being suitable for retro-reflection.
Claim 2
Dependent Claim 76 words
A retro-reflector comprising an indentable metal substrate, transparent material overlying a surface of the substrate, and a mono-layer of glass beads of high refractive index adhered to said transparent material and separated from said substrate by a layer of said transparent material, said surface of the substrate having indentations conforming to the adjacent glass beads and the separation of the glass beads from the substrate surface by said layer of transparent material being suitable for retro-reflection.
Claim 3
Dependent Claim 19 words
A retro-reflector according to claim 1 which includes a layer of transparent material overlying said layer of glass beads.
Claim 4
Dependent Claim 20 words
A retro-reflector according to claim 1 or claim 2 in which the indentable substrate is aluminum or an alloy thereof.
Claim 5
Dependent Claim 23 words
A retro-reflector according to claim 1 or claim 2 in which the indentable substrate is a hard metal clad with a softer metal.
Claim 6
Dependent Claim 84 words
A retro-reflector comprising an indentable metal substrate, a layer of transparent organic polymeric material overlying a surface of the substrate, a mono-layer of glass beads of high refractive index separated from said substrate by said layer of transparent organic polymeric material, and a further layer of transparent organic polymeric material overlying said mono-layer of glass beads, the surface of said substrate having indentations conforming to the adjacent glass beads, and the separation of the glass beads from the conforming indentations being sufficient for retro-reflection.
Claim 7
Dependent Claim 84 words
A retro-reflector comprising an indentable metal substrate, a layer of transparent organic polymeric material overlying a surface of the substrate, a mono-layer of glass beads of high refractive index separated from said substrate by said layer of transparent organic polymeric material, and a further layer of transparent organic polymeric material overlying said mono-layer of glass beads, the surface of said substrate having indentations conforming to the adjacent glass beads, and the separation of the glass beads from the conforming indentations being sufficient for retro-reflection.

References Cited (Backward Citations)

US2407680A Cited
US2543800A Cited
GB1081601A Cited
US3922433A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-07-19 1986-01-18 1986-07-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-07-19 1990-01-18 1990-07-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-07-19 1994-01-18 1994-07-20 $7700.00 Window Closed / Lapsed

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