Patent US3871938A successfully refreshed from Google Patents.
US3871938A
Expired / Lapsed
US
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Process of making leather like sheet material
Assignee: Fujibo Holdings Inc
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Filing: 1972-07-06
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Granted: 1975-03-18
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Expires: 1992-07-06
Abstract
Abstract A leather-like sheet material is manufactured by coating a polymer solution, which contains a major proportion of a polyurethane elastomer, onto a supporting base, coagulating the polymer by dipping the coated base into a non-solvent so as to form a first layer which retains a portion of said non-solvent, coating a second polymer solution which contains a major proportion of a polyurethane elastomer, which solution may be the same or different from the first solution, onto said first coagulated layer, applying a fibrous substrate to the second polymer solution layer, dipping said coated substrate into a nonsolvent to coagulate the second layer, and peeling a product of said coagulated layers and fibrous substrate from said supporting base.
Inventors
- 👤 Takemitsu Takahasi
- 👤 Keigi Yamazaki
- 👤 Hirosi Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 07:54
CPC Classifications
B; B32; B32B; B32B5/00; B32B5/02; B32B5/022; D; D06; D06N; D06N3/00; D06N3/12; D06N3/14; D06N3/145; B32B5/024; B32B2255/00; B32B2255/02; B32B2255/26; Y; Y10; Y10S; Y10S428/00; Y10S428/904; Y10T; Y10T428/00; Y10T428/24; Y10T428/24355; Y10T428/24438; Y10T428/24479; Y10T428/24496; Y10T428/24504; Y10T428/24512; Y10T428/31504; Y10T428/31551; Y10T428/31554
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
190 words
A PROCESS FOR PREPARING A LEATHER-LIKE SHEET OF MATERIAL WHICH COMPRISES: A. APPLYING A POLURETHANE POLYMER TO A SUPPORTING BASE; B. COAGULATING SAID POLYMER SOLUTION TO FORM A POROUS STRUCTURE WHICH CONSTITUTES A FIRST COAGULATE POLYMER ALYER (1) BY IMMERSING THE SUPPORTING BASE AND LAYER IN A NONSOLVENT FOR SAID POLYMER SUCH THAT AT LEAST A PORTION OF SAID NON-SOLVENT IS RETRAINED IN THE PORES OF SAID LAYER; C. APPLYING A SECOND LAYER OF A POLYURETHANE POLYMER SOLUTION ONTO SAID FIRST COAGULATED LAYER (1), WHEREBY THE NON-SOLVENT WHICH IS RETAINED IN THE PORES OF SAID FIRST LAYER ACTS TO COAGULATE THE SECOND LAYER AT THE INTERFACE BETWEEN SAID LAYERS; D. APPLYING A FIBROUS SUBSTRATE TO SAID SECOND LAYER TO FORM A COMPOSITE; E. COAGULATING SAID SECOND LAYER BY IMMERSING THE COMPOSITE IN A NON-SOLVENT FOR THE POLYMER TO FORM A SECOND COAGULATED POLYMER LAYER (II); F. PEELING THE RESULTING COMOPOSITE WHICH CONSISTS OF SAID FIRST COAGULATING LAYER (1), SAID SECOND COAGULATED LAYER (11), AND SAID FIBROUS SUBSTRATE, FROM ITS SUPPORTING BASE TO YIELD THE PRODUCT; AND G. REMOVING THE SOLVENT FROM THE RESULTING PRODUCT BY WASHING WITH WATER AND DRYING.
Claim 2
Dependent Claim
190 words
A PROCESS FOR PREPARING A LEATHER-LIKE SHEET OF MATERIAL WHICH COMPRISES: A. APPLYING A POLURETHANE POLYMER TO A SUPPORTING BASE; B. COAGULATING SAID POLYMER SOLUTION TO FORM A POROUS STRUCTURE WHICH CONSTITUTES A FIRST COAGULATE POLYMER ALYER (1) BY IMMERSING THE SUPPORTING BASE AND LAYER IN A NONSOLVENT FOR SAID POLYMER SUCH THAT AT LEAST A PORTION OF SAID NON-SOLVENT IS RETRAINED IN THE PORES OF SAID LAYER; C. APPLYING A SECOND LAYER OF A POLYURETHANE POLYMER SOLUTION ONTO SAID FIRST COAGULATED LAYER (1), WHEREBY THE NON-SOLVENT WHICH IS RETAINED IN THE PORES OF SAID FIRST LAYER ACTS TO COAGULATE THE SECOND LAYER AT THE INTERFACE BETWEEN SAID LAYERS; D. APPLYING A FIBROUS SUBSTRATE TO SAID SECOND LAYER TO FORM A COMPOSITE; E. COAGULATING SAID SECOND LAYER BY IMMERSING THE COMPOSITE IN A NON-SOLVENT FOR THE POLYMER TO FORM A SECOND COAGULATED POLYMER LAYER (II); F. PEELING THE RESULTING COMOPOSITE WHICH CONSISTS OF SAID FIRST COAGULATING LAYER (1), SAID SECOND COAGULATED LAYER (11), AND SAID FIBROUS SUBSTRATE, FROM ITS SUPPORTING BASE TO YIELD THE PRODUCT; AND G. REMOVING THE SOLVENT FROM THE RESULTING PRODUCT BY WASHING WITH WATER AND DRYING.
Claim 3
Dependent Claim
48 words
The process of claim 1, wherein steps (c) and (d) are performed by applying a second layer of a polymer solution onto a fibrous substrate to form a laminate, superimposing the resulting laminate on the first coagulated layer which retains a quantity of non-solvent, to form a composite.
Claim 4
Dependent Claim
28 words
The process of claim 1, wherein step (e) is performed by coagulating the second layer by spraying a non-solvent onto the open side of the fibrous sheet material.
Claim 5
Dependent Claim
44 words
The process of claim 1 wherein the polymer is substantially a polyurethane elastomer and the non-solvent is water or an aqueous solution and wherein coagulation is caused by replacement of the polymer solution with a non-solvent which is miscible with the solvent and water.
Claim 6
Dependent Claim
27 words
The process of claim 1, wherein the polymer solution is a composition comprising a polyurethane elastomer, a solvent for the polymer, and coloring material and other additives.
Claim 7
Dependent Claim
25 words
The process of claim 1, wherein the supporting base is an endless belt of a substance which is not damageable by water or said solvent.
Claim 8
Dependent Claim
44 words
the process of claim 1, wherein the first polymer solution is applied to a thickness of 0.05 - 5 mm and the second layer of polymer solution is applied so as to be from 0.1 - 10 times the thickness of the first layer.
Claim 9
Dependent Claim
18 words
The process of claim 1, wherein the polymer solution has a viscosity of from 3,000 to 120,000 cps.
Claim 10
Dependent Claim
17 words
The process of claim 1, wherein the non-solvent is water, ethylene glycol, glycol ether, or an alcohol.
Claim 11
Dependent Claim
30 words
The process of claim 1, wherein the portion of non-solvent retained in said first coagulated layer (I) is more than 50% of the dry weight of the first coagulated layer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-17 | 1978-09-16 | 1979-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-17 | 1982-09-16 | 1983-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-17 | 1986-09-16 | 1987-03-18 | $7700.00 | Window Closed / Lapsed |