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US4937134A Expired / Lapsed US ⏱️ 0.0 years remaining

Elastomeric optical interference films

Assignee: 3M Innovative Properties Co
•
Filing: 1989-04-17
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Granted: 1990-06-26
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Expires: 2009-04-17
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Abstract

Abstract The present invention provides improved elastomeric interference films which are readily coextruded, have improved transparency, and have greater mismatches of refractive indices than those of the prior art. An improved elastomeric optical interference film comprising at least 100 alternating layers of at least first and second divergent substantially transparent elastomeric polymeric materials is provided. Adjacent layers of the first and second polymeric materials differ from each other in refractive index by at least about 0.05, and the thickness of the layers is from about 0.05 to about 0.5 micrometers. Stretching the films results in different wavelengths of light being reflected.

Inventors

  • 👤 Walter J. Schrenk
  • 👤 William E. Shrum
  • 👤 John A. Wheatley

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 21:01
CPC Classifications
B; B32; B32B; B32B7/00; B32B7/02; B32B7/023; B32B27/00; B32B27/32; B32B27/06; B32B27/08; B32B27/34; B32B3/00; B32B3/26; B32B3/263; G; G02; G02B; G02B5/00; G02B5/20; G02B5/28; G02B5/285; G02B5/287; B32B2250/00; B32B2250/05; B32B2307/00; B32B2307/40; B32B2307/412; B32B2375/00; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/31504; Y10T428/31551; Y10T428/31554; Y10T428/31562; Y10T428/31565; Y10T428/31725; Y10T428/31736; Y10T428/31786

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 89 words
An elastomeric optical interference film comprising at least 100 alternating layers of at least first and second divergent substantially transparent elastomeric polymeric materials, wherein said first and second polymeric materials are selected from the group consisting of polytetramethylene glycol ether thermoplastic polyurethanes, polyadipate ester thermoplastic polyurethanes, polyether block amides, and flexible copolyesters, and wherein adjacent layers of said first and second polymeric materials differ from each other in refractive index by at least about 0.05 and the thickness of said layers is from about 0.05 to about 0.5 micrometers.
Claim 2
Dependent Claim 89 words
An elastomeric optical interference film comprising at least 100 alternating layers of at least first and second divergent substantially transparent elastomeric polymeric materials, wherein said first and second polymeric materials are selected from the group consisting of polytetramethylene glycol ether thermoplastic polyurethanes, polyadipate ester thermoplastic polyurethanes, polyether block amides, and flexible copolyesters, and wherein adjacent layers of said first and second polymeric materials differ from each other in refractive index by at least about 0.05 and the thickness of said layers is from about 0.05 to about 0.5 micrometers.
Claim 3
Dependent Claim 22 words
The elastomeric optical interference film of claim 1 in which the layers of said first and second polymeric materials vary in thickness.
Claim 4
Dependent Claim 30 words
The elastomeric optical interference film of claim 1 in which the layers of either or both of said first and second polymeric material are arranged in a generally increasing thickness.
Claim 5
Dependent Claim 24 words
The elastomeric optical interference film of claim 1 in which both of said first and second polymeric materials are polytetramethylene glycol ether thermoplastic polyurethanes.
Claim 6
Dependent Claim 30 words
The elastomeric optical interference film of claim 1 in which said first polymeric material is a polyadipate ester thermoplastic polyurethane and said second polymeric material is a polyether block amide.
Claim 7
Dependent Claim 31 words
The elastomeric optical interference film of claim 1 in which said first polymeric material is a polytetramethylene glycol ether thermoplastic polyurethane and said second polymeric material is a polyether block amide.
Claim 8
Dependent Claim 29 words
The elastomeric optical interference film of claim 1 in which said first polymeric material is a polytetramethylene glycol ether thermoplastic polyurethane and said second polymeric material is a copolyester.
Claim 9
Dependent Claim 17 words
The elastomeric optical interference film of claim 1 in which said film reflects visible wavelengths of light.
Claim 10
Dependent Claim 28 words
The elastomeric optical interference film of claim 1 in which said first and second polymeric materials differ from each other in refractive index by at least about 0.06.
Claim 11
Dependent Claim 34 words
The elastomeric optical interference film of claim 1 in which the layers of said film are varied in thickness by stretching, whereby said film reflects different wavelengths of light as said thickness is varied.
Claim 12
Dependent Claim 23 words
The elastomeric optical interference film of claim 10 in which said layers recover substantially their original thickness in the absence of stretching forces.
Claim 13
Dependent Claim 20 words
The elastomeric optical interference film of claim 1 in which said film reflects infrared wavelengths when in an unstretched condition.
Claim 14
Dependent Claim 20 words
The elastomeric optical interference film of claim 12 in which said film reflects ultraviolet wavelengths when in a stretched condition.
Claim 15
Dependent Claim 58 words
The elastomeric optical interference film of claim 1 including at least one skin layer on an exterior surface of said film, said skin layer comprising a blend of (a) a substantially transparent elastomeric polymeric material and (b) a substantially transparent, nonelastomeric polymeric material having substantially the same index of refraction as said elastomeric polymeric material in said blend.
Claim 16
Dependent Claim 18 words
The elastomeric optical interference film of claim 14 including skin layers on both exterior surfaces of said film.
Claim 17
Dependent Claim 35 words
The elastomeric optical interference film of claim 14 in which said elastomeric polymeric material in said skin layer is one of said first and second elastomeric polymeric materials in said alternating layers in said film.
Claim 18
Dependent Claim 30 words
The elastomeric optical interference film of claim 14 in which said nonelastomeric polymeric material is present in said blend in an amount between about 0.5 to about 10% by weight.
Claim 19
Dependent Claim 16 words
The elastomeric optical interference film of claim 14 in which said nonelastomeric polymeric material is polypropylene.
Claim 20
Dependent Claim 24 words
The elastomeric optical interference film of claim 14 in which said skin layer comprises a blend of a polyether block amide elastomer and polypropylene.
Claim 21
Dependent Claim 30 words
The elastomeric optical interference film of claim 19 in which said skin layer comprises 95% by weight of said polyether block amide elastomer and 5% by weight of said polypropylene.
Claim 22
Dependent Claim 141 words
An elastomeric optical interference film comprising at least 100 alternating layers of at least first and second divergent substantially transparent elastomeric polymeric materials, wherein said first and second polymeric materials are selected from the group consisting of polytetramethylene glycol ether thermoplastic polyurethanes, polyadipate ester thermoplastic polyurethanes, polyether block amides, and flexible copolyesters, and wherein adjacent layers of said first and second polymeric materials differ from each other in refractive index by at least about 0.05 and the thickness of said layers is from about 0.05 to about 0.5 micrometers, said film including at least one skin layer on an exterior surface of said film, said skin layer comprising a blend of (a) a substantially transparent, elastomeric polymeric material and (b) a substantially transparent, nonelastomeric polymeric material having substantially the same index of refraction as said elastomeric polymeric material in said blend.
Claim 23
Dependent Claim 141 words
An elastomeric optical interference film comprising at least 100 alternating layers of at least first and second divergent substantially transparent elastomeric polymeric materials, wherein said first and second polymeric materials are selected from the group consisting of polytetramethylene glycol ether thermoplastic polyurethanes, polyadipate ester thermoplastic polyurethanes, polyether block amides, and flexible copolyesters, and wherein adjacent layers of said first and second polymeric materials differ from each other in refractive index by at least about 0.05 and the thickness of said layers is from about 0.05 to about 0.5 micrometers, said film including at least one skin layer on an exterior surface of said film, said skin layer comprising a blend of (a) a substantially transparent, elastomeric polymeric material and (b) a substantially transparent, nonelastomeric polymeric material having substantially the same index of refraction as said elastomeric polymeric material in said blend.
Claim 24
Dependent Claim 35 words
The elastomeric optical interference film of claim 21 in which said elastomeric polymeric material in said skin layer is one of said first and second elastomeric polymeric materials in said alternating layers in said film.
Claim 25
Dependent Claim 32 words
The elastomeric optical interference film of claim 21 in which said skin layer comprises a blend of 95% by weight of a polyether block amide elastomer and 5% by weight of polypropylene.

References Cited (Backward Citations)

US3711176A Cited
US4310584A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-06-25 1993-12-25 1994-06-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-06-25 1997-12-25 1998-06-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-06-25 2001-12-25 2002-06-26 $7700.00 Window Closed / Lapsed

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