Patent US3969972A successfully refreshed from Google Patents.
Patent US4876033A successfully refreshed from Google Patents.
US4876033A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Moulded bodies containing carbon
Assignee: Bayer AG
•
Filing: 1988-04-25
•
Granted: 1989-10-24
•
Expires: 2008-04-25
Abstract
Abstract This invention relates to carbon-containing moulded bodies based on thermoplastic polycarbonates and thermoplastic polyalkylene terephtalates with an addition of carbon black and graphite and to a process for the production of these moulded bodies.
Inventors
- 👤 Heinz-Jurgen Dziurla
- 👤 Dieter Freitag
- 👤 Werner Waldenrath
- 👤 Claus Burkhardt
- 👤 Bernhard Schulte
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:12
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/02; C08K3/04; C08L; C08L69/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
128 words
A process for the production of articles comprising (i) intimately mixing a thermoplastic polycarbonate with a first mixture of carbon black and graphite powder or dust to produce a second mixture, (ii) working up said second mixture under degassing conditions to produce a granulate, (iii) mixing said granulate with a thermoplastic polyalkylene terephthalate to produce a blend, (iv) molding said blend by extrusion or by injection, said blend comprising 55 to 85% thermoplastic polycarbonate, 5 to 30% polyalkylene terephthalate and 10 to 35% said first mixture, said first mixture being characterized in that the weight ratio of said carbon black to said graphite is in the range of from 5:1 to 1:3 and said graphite being characterized in that its average particle size is up to 5 mm.
Claim 2
Dependent Claim
128 words
A process for the production of articles comprising (i) intimately mixing a thermoplastic polycarbonate with a first mixture of carbon black and graphite powder or dust to produce a second mixture, (ii) working up said second mixture under degassing conditions to produce a granulate, (iii) mixing said granulate with a thermoplastic polyalkylene terephthalate to produce a blend, (iv) molding said blend by extrusion or by injection, said blend comprising 55 to 85% thermoplastic polycarbonate, 5 to 30% polyalkylene terephthalate and 10 to 35% said first mixture, said first mixture being characterized in that the weight ratio of said carbon black to said graphite is in the range of from 5:1 to 1:3 and said graphite being characterized in that its average particle size is up to 5 mm.
Claim 3
Dependent Claim
83 words
Carbon-containing moulded bodies produced by the process of claim 1 and comprising: (a) 55% by weight to 85% by weight of thermoplastic polycarbonate, (b) 30% by weight to 5% by weight of thermoplastic polyalkylene terephthalate, and (c) 35% by weight to 10% by weight of carbon black and graphite, in which the ratio by weight of carbon black to graphite is in the range of from 5:1 to 1:3 and the sum of percentages by weight of components (a)+(b)+(c) is 100% by weight.
Claim 4
Dependent Claim
26 words
Moulded bodies according to claim 2, in which the ratio by weight of carbon black to graphite is in the range of from 3:2 to 2:3.
Claim 5
Dependent Claim
15 words
The process of claim 1 wherein said average particle size is up to 1 mm.
Claim 6
Dependent Claim
23 words
The process of claim 1 wherein said polyalkylene terephthalate is present in said blend in an amount of 15 to 30% by weight.
Claim 7
Dependent Claim
17 words
The process of claim 1 wherein said weight ratio is in the range of 3:2 to 2:3.
Claim 8
Dependent Claim
10 words
A molded article produced by the process of claim 5.
Claim 9
Dependent Claim
10 words
A molded article produced by the process of claim 6.
References Cited (Backward Citations)
US3035955A
Cited
US3218372A
Cited
US4161469A
Cited
US4351745A
Cited
US4559164A
Cited
US4515925A
Cited
EP0120394A1
Cited
EP0141310A2
Cited
US4596670A
Cited
US4599262A
Cited
EP0209033A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-23 | 1993-04-24 | 1993-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-23 | 1997-04-24 | 1997-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-23 | 2001-04-24 | 2001-10-24 | $7700.00 | Window Closed / Lapsed |