Laminar structure of polycarbonate

• US 4,519,154 A
• Filed: 08/30/1982
• Issued: 05/28/1985
• Est. Priority Date: 03/30/1982
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Molari, Richard E. Jr.
• Primary Examiner(s): SLUBY, PATRICIA
• Application Number:
  US06/412,979
• Time in Patent Office: 1,002 Days
• Field of Search: 428/412, 428/421, 428/407, 428/913, 428/406, 428/402, 40/582, 40/583, 40/615
• US Class Current: 40/615
• CPC Class Codes: B32B 2307/416 Reflective
• CPC Class Codes: B32B 2590/00 Signboards, advertising panels, road signs
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/18 characterised by the use of special additives
• CPC Class Codes: B32B 27/304 comprising vinyl halide (co)polymers, e.g. PVC, PVDC, PVF, PVDF
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: G09F 13/16 Signs formed of or incorporating reflecting elements or surfaces, e.g. warning signs having triangular or other geometrical shape
• CPC Class Codes: Y10S 428/913 Material designed to be responsive to temperature, light, moisture
• CPC Class Codes: Y10T 428/24876 Intermediate layer contains particulate material [e.g., pigment, etc.]
• CPC Class Codes: Y10T 428/24917 including metal layer
• CPC Class Codes: Y10T 428/24926 including ceramic, glass, porcelain or quartz layer
• CPC Class Codes: Y10T 428/24934 including paper layer
• CPC Class Codes: Y10T 428/251 Mica
• CPC Class Codes: Y10T 428/252 Glass or ceramic [i.e., fired or glazed clay, cement, etc.] [porcelain, quartz, etc.]
• CPC Class Codes: Y10T 428/259 Silicic material
• CPC Class Codes: Y10T 428/2996 Glass particles or spheres
• CPC Class Codes: Y10T 428/31507 Of polycarbonate
• CPC Class Codes: Y10T 428/31518 Next to glass or quartz
• CPC Class Codes: Y10T 428/31529 Next to metal
• CPC Class Codes: Y10T 428/3154 Of fluorinated addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31601 : Quartz or glass
• CPC Class Codes: Y10T 428/31605 : Next to free metal
• CPC Class Codes: Y10T 428/31667 : Next to addition polymer from unsaturated monomers, or aldehyde or ketone condensation product
• CPC Class Codes: Y10T 428/31928 : Ester, halide or nitrile of addition polymer

Abstract

A laminar polycarbonate resin structure comprising a polycarbonate resin core lamina, an ultraviolet radiation absorbing back lamina bonded to the rear face of said core lamina, and a light reflecting front lamina bonded to the front face of said core lamina. This laminar structure is useful for making road signs and markers.

Claims

1. An improved light reflecting sign consisting essentially of, in combination:

(i) a core structure having a rear face and a front face; and

(ii) a front visible light reflecting laminate disposed on and bonded to said front face of said core structure;

the improvement comprising said core structure being comprised of at least one ply comprised of a high molecular weight aromatic polycarbonate resin and having disposed on and bonded to said rear face thereof a back ultraviolet radiation protective ply.

2. The sign of claim 1 wherein said back ply is comprised of an organic polymeric material containing an amount of ultraviolet radiation stabilizer effective to prevent transmission of ultraviolet radiation to the underlying core structure.

3. The sign of claim 2 wherein said organic polymeric material is polyvinyl fluoride.

4. The sign of claim 3 wherein said ultraviolet radiation stabilizer is a polymer having the formula ##STR9## wherein R³ and R⁴ are independently selected from the group consisting of hydrogen, alkyl groups having 1-6 carbon atoms, chloroalkyl, and phenyl;

R⁵, R⁶, R⁷, R⁸, R⁹ and R¹⁰ are independently selected from the group consisting of hydrogen, alkyl, alkoxy and halogen;

A is an aryl radical; and

n is an integer having a value of at least two.

5. The structure of claim 4 wherein R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹ and R¹⁰ are hydrogen and A is a phenyl radical.

6. The sign of claim 4 wherein said polyvinyl fluoride back ply contains from about 0.1 to about 10% by weight of said ultraviolet radiation stabilizer.

7. The sign of claim 3 wherein said ultraviolet radiation stabilizer is a polymer having recurring structural units of the formula ##STR10## wherein R¹¹ is selected from the group consisting of hydrogen, halogen and alkyl;

R¹² is selected from the group consisting of hydrogen, halogen, hydroxy, alkoxy, and alkyl; and

n'"'"' is a positive integer having a value of from 1 to 3 inclusive;

wherein at least 10% of said units of said polymeric compound have attached to the benzene ring a radical of the formula ##STR11##

8. The sign of claim 2 wherein said front light reflective lamina is comprised of a light returning layer of small transparent spheres, internal light-reflecting means underlying said spheres and positioned so as to produce reflex reflection, and a continuous overlying transparent solid covering united and conforming to the front extremities of said spheres and having a flat front face.

9. The sign of claim 8 wherein said structure is a road sign or marker.

10. The sign of claim 1 wherein said back ply is opaque to ultraviolet radiation.

11. The sign of claim 10 wherein said back ply is comprised of polyvinyl fluoride containing an amount of pigments effective to render it opaque to ultraviolet radiation.

12. The sign of claim 11 wherein said front light reflective lamina is comprised of a light returning layer of small transparent spheres, internal light-reflecting means underlying said spheres and positioned so as to produce reflex reflection, and a continuous overlying transparent solid covering united and conforming to the front extremities of said spheres and having a flat front face.

13. The sign of claim 12 wherein said sign is a road sign or marker.