Lamellar polymeric body

• US 5,217,794 A
• Filed: 01/22/1991
• Issued: 06/08/1993
• Est. Priority Date: 01/22/1991
• Status: Expired due to Term

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: The Dow Chemical Company (Dow, Inc.)
• Inventors: Schrenk, Walter J.
• Primary Examiner(s): Ryan, Patrick J.
• Assistant Examiner(s): LAM, CATHY FONG FONG
• Application Number:
  US07/643,611
• Time in Patent Office: 868 Days
• Field of Search: 428/220, 428/912.2, 428/913
• US Class Current: 428/220
• CPC Class Codes: B29C 48/00 Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor extrusion blow-moulding B29C49/04
• CPC Class Codes: B29C 48/07 Flat, e.g. panels
• CPC Class Codes: B29C 48/08 flexible, e.g. films
• CPC Class Codes: B29C 48/16 Articles comprising two or more components, e.g. co-extruded layers
• CPC Class Codes: B29C 48/304 specially adapted for bringing together components, e.g. melts within the die
• CPC Class Codes: B29C 70/585 incorporation of light reflecting filler, e.g. lamellae to obtain pearlescent effet partially embedding reflective elements into the surface of or support B29D11/00615
• CPC Class Codes: B29D 11/00 Producing optical elements, e.g. lenses or prisms grinding or polishing of optical elements B24B; constructional form of optical elements G02B; optical parts of spectacles G02C7/00
• CPC Class Codes: B29K 2995/0031 Refractive
• CPC Class Codes: B32B 2250/42 Alternating layers, e.g. ABAB(C), AABBAABB(C)
• CPC Class Codes: B32B 2307/416 Reflective
• CPC Class Codes: B32B 2307/724 Permeability to gases, adsorption
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 3/18 characterised by an internal layer formed of separate pieces of material which are juxtaposed side-by-side B32B5/02 takes precedence
• CPC Class Codes: B32B 3/22 of spaced pieces not used
• CPC Class Codes: G02B 5/287 comprising at least one layer of organic material
• CPC Class Codes: G02B 5/3008 comprising dielectric particles, e.g. birefringent crystals embedded in a matrix
• CPC Class Codes: G02B 5/305 including organic materials, e.g. polymeric layers
• CPC Class Codes: Y10S 428/913 Material designed to be responsive to temperature, light, moisture

Abstract

A lamellar polymeric body which may be reflective and which contains no metals and method of making it are provided. The body can be fabricated and/or post-formed into a variety of parts without alteration of its appearance. The body includes discontinuous layers of at least one polymeric material within a matrix of another polymeric material, which polymers differ in refractive index. The layers of the polymeric material may be either optically thick, optically thin, or optically very thin.

Claims

1. A lamellar reflective polymeric body of at least first and second diverse polymeric materials, said body having at least first and second major surfaces, the body comprising a plurality of discontinuous layers of said first polymeric material within a matrix of said second polymeric material, and wherein said discontinuous layers of said first polymeric material have their major interfaces aligned substantially parallel to the major surfaces of said body, the number of layers of said first polymeric material being sufficient such that at least 30% of light incident on said body is reflected, the individual layers of said first polymeric material in said body, and those portions of said second polymeric material sandwiched between said individual layers of said first polymeric material, having an optical thickness of not more than 0.09 micrometers, between 0.09 micrometers and 0.45 micrometers, or not less than 0.45 micrometers, and wherein said first and second polymeric materials differ from each other in refractive index by at least about 0.03.

2. The reflective polymeric body of claim 1 in which said first polymeric material is polymethyl methacrylate and said second polymeric material is polystyrene.

3. The reflective polymeric body of claim 1 in which said second polymeric material is elastomeric.

4. The reflective polymeric body of claim 1 in which both of said first and second polymeric materials are elastomeric.

5. The reflective polymeric body of claim 1 in which a fluid is present at a plurality of said major interfaces of said first and second polymeric materials.

6. The reflective polymeric body of claim 1 in which said first polymeric material is a gas barrier material.

7. The reflective polymeric body of claim 1 in which at least a portion of the layers of said first polymeric material have an optical thickness of between 0.09 micrometers and 0.45 micrometers and produces a colored, iridescent body.

8. The reflective polymeric body of claim 1 in which said polymeric body is thermoformable.

9. The lamellar reflective body of claim 1 wherein said layers of said first polymeric material are substantially continuous in a first plane parallel to one of said major surfaces of said body and discontinuous in a second plane transverse to said first plane.

10. The lamellar reflective body of claim 1 wherein said layers of said first polymeric material are substantially discontinuous along planes parallel and transverse to one of said major surfaces of said body.

11. The reflective polymeric body of claim 1 in which a coloring agent is incorporated into at least one layer of said polymeric body.

12. The reflective polymeric body of claim 11 in which said coloring agent is selected from the group consisting of pigments and dyes.

13. The reflective polymeric body of claim 11 in which said coloring agent is incorporated into at least one interior layer of said polymeric body.

14. The reflective polymeric body of claim 1 in which at least 75% of said individual layers of said first polymeric material and those portions of said second polymeric material sandwiched therebetween have an optical thickness of at least 0.45 micrometers.

15. A lamellar reflective polymeric body of at least first and second diverse polymeric materials, said body having at least first and second major surfaces, the body comprising a plurality of discontinuous individual layers within a matrix of a third polymeric material, each discontinuous individual layer comprising a plurality of alternating layers of said first and second polymeric materials within said matrix, and wherein said alternating layers of said first and second polymeric materials have their major interfaces aligned substantially parallel to the major surfaces of said body, the number of alternating layers of said first and second polymeric materials being sufficient such that at least 30% of light incident on said body is reflected, the individual layers of said first and second polymeric materials having optical thicknesses of not more than 0.09 micrometers, between 0.09 micrometers and 0.45 micrometers, or not less than 0.45 micrometers, and wherein said first and second polymeric materials differ from each other in refractive index by at least about 0.03.

16. The reflective polymeric body of claim 15 in which said third polymeric material is elastomeric.

17. The reflective polymeric body of claim 15 in which said first, second, and third polymeric materials are elastomeric.

18. The reflective polymeric body of claim 15 in which at least a portion of the layers of said first polymeric material have an optical thickness of between 0.09 micrometers and 0.45 micrometers and produces a colored, iridescent body.

19. The reflective polymeric body of claim 15 in which said polymeric body is thermoformable.

20. The lamellar reflective body of claim 15 wherein said layers of said first and second polymeric materials are substantially continuous in a first plane parallel to one of said major surfaces of said body and discontinuous in a second plane transverse to said first plane.

21. The lamellar reflective body of claim 15 wherein said layers of said first and second polymeric materials are substantially discontinuous along planes parallel and transverse to one of said major surfaces of said body.

22. The reflective polymeric body of claim 15 in which a coloring agent is incorporated into at least one layer of said polymeric body.

23. The reflective polymeric body of claim 22 in which said coloring agent is selected from the group consisting of pigments and dyes.

24. The reflective polymeric body of claim 22 in which said coloring agent is incorporated into at least one interior layer of said polymeric body.

25. The reflective polymeric body of claim 15 in which at least 75% of said individual layers of said first and second polymeric materials have an optical thickness of at least 0.45 micrometers.

26. A lamellar polymeric body of at least first and second diverse polymeric materials, said body having at least first and second major surfaces, the body comprising a plurality of layers of said first polymeric material within a matrix of said second polymeric material, and further wherein said layers of said first polymeric material are substantially discontinuous along planes parallel and/or transverse to one of said major surfaces of said body.

27. The polymeric body of claim 26 in which said first polymeric material is rubbery and said second polymeric material is brittle.

28. The polymeric body of claim 26 wherein said first polymeric material is a gas barrier material.