US4241189A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wear-resistant flexible sheet material and a method for its manufacture
Assignee: General Foam Products Ltd
•
Filing: 1978-02-02
•
Granted: 1980-12-23
•
Expires: 1998-02-02
Abstract
Abstract A wear-resistant flexible sheet material, suitable for use as outer soles on footwear, is produced by pressing reconstituted polyurethane foam sheets in the substantial absence of air at temperatures above 150° C. The sheets should have a density exceeding 15 lb/ft 3 and are further densified by the hot pressing. The sheets are preferably pre-heated to 175°-210° C. and pressed under a pressure of 5 to 30 tons/ft 2 for periods of up to 5 minutes. The sheets may be embossed or smooth surfaced and may contain pigments, plasticizers and other additives.
Inventors
- 👤 Neville M. Sheldon
- 👤 Alfred Stern
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:26
CPC Classifications
B; B29; B29C; B29C67/00; B29C67/20; B29C67/207; B29C44/00; B29C44/02; B29C44/10; B29L; B29L2031/00; B29L2031/48; B29L2031/50; B29L2031/504; Y; Y10; Y10S; Y10S264/00; Y10S264/07; Y10S521/00; Y10S521/918
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
68 words
A process for making wear-resistant flexible sheet material comprising the steps of: providing a sheet of dense flexible reconstituted polyurethane foam material having a density exceeding about 15 lb/ft 3 ; and subjecting said sheet to a pressure of about 5 to 30 tons/ft 2 at a temperature above about 150° C. in the substantial absence of air whereby said sheet is densified and its wear resistance enhanced.
Claim 2
Dependent Claim
68 words
A process for making wear-resistant flexible sheet material comprising the steps of: providing a sheet of dense flexible reconstituted polyurethane foam material having a density exceeding about 15 lb/ft 3 ; and subjecting said sheet to a pressure of about 5 to 30 tons/ft 2 at a temperature above about 150° C. in the substantial absence of air whereby said sheet is densified and its wear resistance enhanced.
Claim 3
Dependent Claim
23 words
The process of claim 1 wherein said pressing is carried out at a temperature in the range of about 150° to 250° C.
Claim 4
Dependent Claim
35 words
The process of claim 1 wherein said sheet is preheated to a temperature in the range of about 150° to 250° C. for a period of about 1 to about 5 minutes prior to pressing.
Claim 5
Dependent Claim
26 words
The process of claim 1 wherein said pressing is carried out for a period of 1 to 4 minutes depending on the thickness of said sheet.
Claim 6
Dependent Claim
15 words
The process of claim 1 wherein the polyurethane is of the polyether or polyester type.
Claim 7
Dependent Claim
33 words
The process of claim 1 wherein a material selected from the group consisting of a flame-retardant, a colorant, a deodorant, a fungicide and a plasticizer is added to the reconstituted foam starting material.
Claim 8
Dependent Claim
11 words
Wear-resistant flexible sheet material made by the process of claim 1.
Claim 9
Dependent Claim
102 words
A process for making wear-resistant flexible sheet material comprising the steps of: providing a sheet of dense flexible reconstituted foam composed at least predominantly of polyurethane; heating said sheet to a temperature in the range of about 150° to 250° C.; and compressing said sheet at said temperature between heated platens to the substantial exclusion of air from all but peripheral portions of said sheet and under a pressure in the approximate range 5 to 30 tons/ft 2 for a period of about 1 to about 4 minutes to a final sheet thickness in the approximate range of 1.2 to 18 mm.
Claim 10
Dependent Claim
102 words
A process for making wear-resistant flexible sheet material comprising the steps of: providing a sheet of dense flexible reconstituted foam composed at least predominantly of polyurethane; heating said sheet to a temperature in the range of about 150° to 250° C.; and compressing said sheet at said temperature between heated platens to the substantial exclusion of air from all but peripheral portions of said sheet and under a pressure in the approximate range 5 to 30 tons/ft 2 for a period of about 1 to about 4 minutes to a final sheet thickness in the approximate range of 1.2 to 18 mm.
Claim 11
Dependent Claim
30 words
The process of claim 8 wherein said sheets are heated to a temperature of 175° to 210° C. over a period of 1 to 5 minutes prior to said pressing.
Claim 12
Dependent Claim
70 words
A process for making wear-resistant flexible sheet material comprising the steps of: providing a sheet of dense flexible reconstituted polyether type polyurethane foam material having a density exceeding about 15 lb/ft 3 ; and subjecting said sheet to a pressure of about 5 to 30 tons/ft 2 at a temperature above about 150° C. in the substantial absence of air whereby said sheet is densified and its wear resistance enhanced.
Claim 13
Dependent Claim
70 words
A process for making wear-resistant flexible sheet material comprising the steps of: providing a sheet of dense flexible reconstituted polyether type polyurethane foam material having a density exceeding about 15 lb/ft 3 ; and subjecting said sheet to a pressure of about 5 to 30 tons/ft 2 at a temperature above about 150° C. in the substantial absence of air whereby said sheet is densified and its wear resistance enhanced.
Claim 14
Dependent Claim
23 words
The process for making wear-resistant flexible sheet material of claim 10, wherein the temperature is in the range of 150° to 250° C.
Claim 15
Dependent Claim
32 words
The process for making wear-resistant flexible sheet material of claim 10, wherein the polyurethane foam material is preheated at a temperature of about 150° to 250° C. prior to the pressure treatment.
Claim 16
Dependent Claim
20 words
The process for making wear-resistant flexible sheet material of claim 10, wherein the reconstituted polyurethane foam material is fully cured.
Claim 17
Dependent Claim
11 words
Wear-resistant flexible sheet material made by the process of claim 10.
References Cited (Backward Citations)
US2878153A
Cited
US3035280A
Cited
US2994110A
Cited
US3004293A
Cited
GB976260A
Cited
US3263010A
Cited
US3354578A
Cited
US3452122A
Cited
US3452127A
Cited
GB1337413A
Cited
US3746610A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-12-23 | 1984-06-23 | 1984-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-23 | 1988-06-23 | 1988-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-23 | 1992-06-23 | 1992-12-23 | $7700.00 | Window Closed / Lapsed |