US4515925A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polycarbonate/polybutylene terephthalate film
Assignee: Bayer AG
•
Filing: 1983-09-28
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Granted: 1985-05-07
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Expires: 2003-09-28
Abstract
Abstract Mixtures of (A) from 50 to 90% by weight of aromatic polycarbonate and (B) from 10 to 50% by weight of polybutylene terephthalate, the percent by weight being based on the total of (A) and (B) are used to produce novel films.
Inventors
- 👤 Frank Kleiner
- 👤 Rolf Kubens
- 👤 Eckart Reese
- 👤 Joachim Wank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:03
CPC Classifications
C; C08; C08L; C08L69/00; C08J; C08J5/00; C08J5/18; C08J2369/00; C08J2467/00; C08J2467/02
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
63 words
A film comprising a mixture of A. from 50 to 90% by weight of aromatic polycarbonate, and B. from 10 to 50% by weight of polybutylene terephthalate the % by weight, being based on the total of A and B where after said film is monoaxially stretched, then upon heating said film shrinks in the direction of stretching, but substantially not transverse thereto.
Claim 2
Dependent Claim
63 words
A film comprising a mixture of A. from 50 to 90% by weight of aromatic polycarbonate, and B. from 10 to 50% by weight of polybutylene terephthalate the % by weight, being based on the total of A and B where after said film is monoaxially stretched, then upon heating said film shrinks in the direction of stretching, but substantially not transverse thereto.
Claim 3
Dependent Claim
62 words
A film as claimed in claim 1, wherein the aromatic polycarbonate has been produced from a diphenol corresponding to formula (I): HO--Z--OH (I) wherein Z represents a divalent mono- or polynuclear aromatic radical having from 6 to 30 carbon atoms, and is constructed such that each of the two OH groups is directly bound to one carbon atom of an aromatic ring.
Claim 4
Dependent Claim
57 words
A film as claimed in claim 2, wherein the diphenol corresponds to the formula (II): ##STR3## wherein Y represents a single bond or Y represents, an alkylene or alkylidene radical having from 1 to 7 carbon atoms, a cycloalkylene or cycloalkylidene radical having from 5 to 12 carbon atoms, ##STR4## or a nuclear-alkylated or nuclear-halogenated derivative thereof.
Claim 5
Dependent Claim
55 words
A film as claimed in claim 1 wherein the polybutylene terephthalate has a dicarboxylic acid component and a diol component and wherein the polybutylene therephthalate contains at least 80 mol %, based on the dicarboxylic acid component, of terephthalic acid radicals and at least 80 mol %, based on the diol component of butanediol-1,4 radicals.
Claim 6
Dependent Claim
34 words
A film as claimed in claim 4, wherein the polybutylene terephthalate has been produced only from A and B wherein A comprises therephthalic acid, reactive derivatives thereof or mixtures thereof and B is butanediol-1,4.
Claim 7
Dependent Claim
12 words
A film as claimed in claim 1 which has been monoaxially stretched.
References Cited (Backward Citations)
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US3953539A
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US3956229A
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US4044073A
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Cited
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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) | 1988-05-06 | 1988-11-05 | 1989-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-06 | 1992-11-05 | 1993-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-06 | 1996-11-05 | 1997-05-07 | $7700.00 | Window Closed / Lapsed |