US4217441A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Modified polyester films
Assignee: EIDP Inc
•
Filing: 1978-03-29
•
Granted: 1980-08-12
•
Expires: 1998-03-29
Abstract
Abstract Polyester films are modified by the addition of a high molecular weight polyethylene glycol and an alkali metal salt of a sulfonic acid-substituted dicarboxylic acid ester to the reaction medium during the polymerization process. Films prepared for example, from diesters of terephthalic acid in the presence of the modifiers of this invention exhibit good permeability to water vapor.
Inventors
- 👤 John H. Bayless
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:31
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/68; C08G63/688; C08G63/6884; G; G03; G03C; G03C1/00; G03C1/76; G03C1/795; G03C1/7954
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
51 words
A biaxially oriented, heat set linear polyester film with high water vapor permeability, wherein the polyester is comprised of a reaction product of (1) a glycol diester of a dicarboxylic acid, (2) a high molecular weight polyethylene glycol, and (3) an alkali metal salt of a sulfonic acid-substituted dicarboxylic acid ester.
Claim 2
Dependent Claim
51 words
A biaxially oriented, heat set linear polyester film with high water vapor permeability, wherein the polyester is comprised of a reaction product of (1) a glycol diester of a dicarboxylic acid, (2) a high molecular weight polyethylene glycol, and (3) an alkali metal salt of a sulfonic acid-substituted dicarboxylic acid ester.
Claim 3
Dependent Claim
14 words
The polyester film of claim 1 wherein said glycol diester (1) is bis-2-hydroxyethyl terephthalate.
Claim 4
Dependent Claim
19 words
The polyester film of claim 1 wherein said polyethylene glycol (2) has a molecular weight of 600 to 20,000.
Claim 5
Dependent Claim
19 words
The polyester film of claim 1 wherein said polyethylene glycol (2) has a molecular weight of 2000 to 8000.
Claim 6
Dependent Claim
40 words
The polyester film of claim 1 wherein said alkali metal salt of a sulfonic acid-substituted dicarboxylic acid ester (3) is selected from the group consisting of an alkali-3,5-dicarbomethoxy benzene sulfonic acid, an alkali-1,2-dicarbomethoxy-4-benzene sulfonic acid, and an alkali-3,7-dicarbomethoxy naphthalene-1-sulfonic acid.
Claim 7
Dependent Claim
49 words
The polyester film of claim 1 wherein said polyethylene glycol (2) is used in an amount of 2-12%, and said alkali metal salt of a sulfonic acid-substituted dicarboxylic acid ester (3) is used in an amount of 2-8%, the percentages being in % by weight of the reaction product.
Claim 8
Dependent Claim
63 words
The polyester film of claim 2 wherein said polyethylene glycol (2) has a molecular weight of about 3500 and is used in an amount of about 4-10%, and said alkali metal salt of a sulfonic acid-substituted dicarboxylic acid ester is sodium-3,5-dicarbomethoxy benzene sulfonate and is used in an amount of about 3-6%, the percentage being in % by weight of the reaction product.
Claim 9
Dependent Claim
76 words
A process for preparing a polyester film which comprises synthesizing a polyester of (1) a glycol diester of a dicarboxylic acid, (2) a high molecular weight polyethylene glycol, and (3) an alkali metal salt of a sulfonic acid-substituted dicarboxylic acid ester, casting the polyester into film, and biaxially stretching and heat setting said film to achieve dimensional stability and a permeability to water vapor of about 160-1100 IPV/mil as measured by ASTM Standard Procedure No. F-372-73.
Claim 10
Dependent Claim
76 words
A process for preparing a polyester film which comprises synthesizing a polyester of (1) a glycol diester of a dicarboxylic acid, (2) a high molecular weight polyethylene glycol, and (3) an alkali metal salt of a sulfonic acid-substituted dicarboxylic acid ester, casting the polyester into film, and biaxially stretching and heat setting said film to achieve dimensional stability and a permeability to water vapor of about 160-1100 IPV/mil as measured by ASTM Standard Procedure No. F-372-73.
Claim 11
Dependent Claim
27 words
The process of claim 8 wherein (1) is bis-2-hydroxyethyl terephthalate, (2) is polyethylene glycol with a molecular weight of about 3500, and (3) is sodium-3,5-dicarbomethoxy benzene sulfonate.
Claim 12
Dependent Claim
29 words
The process of either claim 8 or 9 comprising the further step of coating the biaxially stretched and heat set film with at least one photographic silver halide emulsion.
Claim 13
Dependent Claim
16 words
The process of either claim 8, 9 or 10 wherein the polyester film contains carbon black.
References Cited (Backward Citations)
US3018272A
Cited
US3455720A
Cited
US3461468A
Cited
US3560605A
Cited
US3563942A
Cited
US3779993A
Cited
US3853820A
Cited
US4042565A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-08-12 | 1984-02-11 | 1984-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-08-12 | 1988-02-11 | 1988-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-08-12 | 1992-02-11 | 1992-08-12 | $7700.00 | Window Closed / Lapsed |