Method of making a retroreflective laminate

• US 4,104,102 A
• Filed: 08/12/1976
• Issued: 08/01/1978
• Est. Priority Date: 02/24/1975
• Status: Expired due to Term

• Current Assignee: Morgan Adhesives Company (Amcor Plc)
• Original Assignee: Morgan Adhesives Company (Amcor Plc)
• Inventors: Carlson, Russell L., Eagon, Beverly M., Fry, Raymond C.
• Primary Examiner(s): Smith, Ronald H.
• Assistant Examiner(s): Beck, Shrive P.
• Application Number:
  US05/713,790
• Time in Patent Office: 719 Days
• Field of Search: 427/25, 427/27, 427/32, 427/163, 427/33, 427/204, 427/199, 427/411, 350/104, 350/105, 156/298, 156/300, 156/332, 428/40, 428/325, 428/913
• US Class Current: 156/298
• CPC Class Codes: B32B 15/08 of synthetic resin
• CPC Class Codes: B32B 15/20 comprising aluminium or copper B32B15/016 and B32B15/017 take precedence
• CPC Class Codes: B32B 2264/101 Glass
• CPC Class Codes: B32B 2307/40 having particular optical properties light or UV resistant B32B2307/71
• CPC Class Codes: B32B 2311/24 Aluminium
• CPC Class Codes: G02B 5/128 transparent spheres being embedded in matrix
• CPC Class Codes: Y10S 428/913 Material designed to be responsive to temperature, light, moisture
• CPC Class Codes: Y10T 156/109 Embedding of laminae within face of additional laminae
• CPC Class Codes: Y10T 156/1093 with covering of discrete laminae with additional lamina
• CPC Class Codes: Y10T 428/1405 Capsule or particulate matter containing [e.g., sphere, flake, microballoon, etc.]
• CPC Class Codes: Y10T 428/1414 Ceramic, glass, glasslike, vitreous
• CPC Class Codes: Y10T 428/252 Glass or ceramic [i.e., fired or glazed clay, cement, etc.] [porcelain, quartz, etc.]

Abstract

The laminate includes a partially cured, flexible acrylic face sheet having a primer layer on one surface thereof bonded to a binder layer having a layer of reflective glass beads embedded therein and protruding therefrom and a sealer layer on the exposed surfaces of the glass beads, the laminate being completed with a spacer layer bonded to the sealer layer and having a reflective mirror-like thin metal coating on the outer surface thereof. The binder layer, sealer layer and spacer layer, or films are all made from basically the same uncured polyvinyl butyral material. The method of forming the acrylic face layer, the use of soft rubber pressure rolls in bonding a glass bead carrying partial laminate to a preformed spacer film, and the method of making the laminate of the invention and the compositions used therein.

Claims

1. In a method of making a retroreflective laminate, the steps of applying a binder layer to a face layer, applying glass beads to the surface of said binder layer and embedding them in such layer but having said glass beads protruding from said binder layer, applying a liquid sealer layer to the surface of the binder layer and the protruding glass beads, drying to obtain a sealer layer that follows the contour of the protruding glass beads and the binder layer surface on both the inner and outer surfaces of such sealing layer, heating the resultant laminate, and laminating a preformed uniform thickness spacer film to the sealer, glass bead and binder layer under controlled heat conditions to bond the spacer film thereto, the spacer film substantially maintaining its uniform thickness as it is heated and laminated to the sealer-glass bead binder layer, the sealer layer aiding the bonding of the spacer film to the bead-binder surfaces, the spacer film having a metal reflective layer on its outer surface in the completed retroreflective laminate.

2. In a method of making a retroreflective laminate, the steps of applying a binder layer to a face layer, applying glass beads to the surface of said binder layer and embedding them in such layer but having said glass beads protruding from said binder layer, heating the laminate with the glass bead layer thereon, and laminating a preformed uniform thickness spacer film to the glass bead-binder layer under controlled heat conditions to soften the spacer film and shape the spacer film to the contour of the glass beads and provide a uniform coating of such film over the protruding glass beads, the spacer film having a metal reflective layer on its outer surface in the completed retroreflective laminate which is designed to receive light rays on its face layer.

3. In a method of making a retroreflective laminate, the steps of applying a binder layer to a face layer, applying glass beads to the surface of said binder layer and embedding them in such layer but having said glass beads protruding from said binder layer, heating the laminate with the glass bead layer thereon, and laminating a preformed uniform thickness spacer film to the glass bead-binder layer under controlled heat conditions to bond the film and layer together, the spacer film substantially maintaining its uniform thickness as it is heated and laminated to the irregular surface of the glass bead-binder layer, the spacer film having a metal reflective layer on its outer surface for reflecting light rays impinging on the face layer.