US3748758A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Footwear having transparent parts
Assignee: Individual
•
Filing: 1971-11-19
•
Granted: 1973-07-31
•
Expires: 1991-11-19
Abstract
Abstract Footwear including a portion having a layer comprising a temperature or pressure sensitive liquid crystal system which changes color when the footwear flexes, as when the wearer walks. Footwear made at least partly of a transparent plastic material is preferred.
Inventors
- 👤 L Wilchusky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:18
CPC Classifications
A; A43; A43B; A43B1/00; A43B1/0072; A43B1/0027; A43B1/0036
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
20 words
Footwear as set forth in claim 1 in which the layer is placed on a base of the heel portion.
Claim 2
Dependent Claim
23 words
Footwear as set forth in claim 2 and including a top lift secured to the base of said heel portion over said layer.
Claim 3
Dependent Claim
41 words
Footwear as set forth in claim 1 wherein the heel portion comprises a solid base portion, the bottom surface of the base portion includes the layer of liquid crystals and the top of the base portion is a light refractive surface.
Claim 4
Dependent Claim
28 words
Footwear as set forth in claim 4 in which the light refractive surface is substantially planar and extends substantially parallel to the bottom surface of the base portion.
Claim 5
Dependent Claim
26 words
Footwear as set forth in claim 4 in which the light refractive surface is substantially concave with respect to the bottom surface of the base portion.
Claim 6
Dependent Claim
30 words
Footwear as set forth in claim 4 in which the light refractive surface comprises a plurality of facets having radially extending edges emanating from the center of the refractive surface.
Claim 7
Dependent Claim
24 words
Footwear as set forth in claim 4 and including a top lift secured to the bottom surface of the base portion of the heel.
Claim 8
Dependent Claim
44 words
Footwear as set forth in claim 1 in which the liquid crystal layer is applied to a body portion of transparent plastics material and a separate piece of material is placed within said body portion so as to contact and protect the liquid crystals.
Claim 9
Dependent Claim
53 words
Footwear as set forth in claim 1 wherein the liquid crystals are carried in a composite sheet comprising a backing material and a transparent plastics material having a layer of liquid crystals sandwiched therebetween, and said composite sheet is secured to at least one of said body and heel portions of the footwear.
Claim 10
Dependent Claim
20 words
Footwear as set forth in claim 10 wherein the composite sheet is secured to a surface of the heel portion.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |