US4566990A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Synergistic effect of metal flake and metal or metal coated fiber on EMI shielding effectiveness of thermoplastics
Assignee: General Electric Co
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Filing: 1983-10-25
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Granted: 1986-01-28
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Expires: 2003-10-25
Abstract
Abstract Conductive thermoplastic having high EMI shielding effectiveness comprise a thermoplastic condensation polymer and incorporated therein a synergistic combination of metal flake and conductive metal or metal coated fiber.
Inventors
- 👤 Nan-I Liu
- 👤 Roelof van der Meer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:39
CPC Classifications
H; H01; H01B; H01B1/00; H01B1/20; H01B1/22; B; B29; B29B; B29B7/00; B29B7/30; B29B7/58; B29B7/72; B29B7/726; B29B7/80; B29B7/88; B29B7/90; C; C08; C08K; C08K3/00; C08K3/02; C08K3/08; C08K7/00; C08K7/02; C08K7/04; C08K7/06; C08K9/00; C08K9/02; B29B7/34; B29B7/38
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
71 words
A thermoplastic polymeric composition having high electromagnetic interference shielding effectiveness comprising: (a) a thermoplastic resin or resin blend, (b) from about 25 to about 50% by weight based on the total composition of metal flake, and (c) from about 2 to about 12% by weight based on the total composition of metal or metal coated fiber, wherein the weight ratio of flake to fiber is from about 4:1 to about 14:1.
Claim 2
Dependent Claim
71 words
A thermoplastic polymeric composition having high electromagnetic interference shielding effectiveness comprising: (a) a thermoplastic resin or resin blend, (b) from about 25 to about 50% by weight based on the total composition of metal flake, and (c) from about 2 to about 12% by weight based on the total composition of metal or metal coated fiber, wherein the weight ratio of flake to fiber is from about 4:1 to about 14:1.
Claim 3
Dependent Claim
37 words
The composition of claim 1 wherein the thermoplastic resin (a) is selected from the group consisting of polyesters, polycarbonates, polyamides, co-polyetheresters, polypheneylene ethers, co-polyestercarbonates, poly(aryl ether)s, polyamide imides, polyetherimides, polystyrenes, acrylonitrile butadiene styrene copolymers and blends thereof.
Claim 4
Dependent Claim
29 words
A composition as defined in claim 2 wherein the polyester has repeating units of the general formula ##STR16## wherein n is a whole number of from 2 to 4.
Claim 5
Dependent Claim
11 words
The composition of claim 3 wherein the polyester is poly(1,4-butylene terephthalate).
Claim 6
Dependent Claim
11 words
The composition of claim 3 wherein the polyester is poly(ethylene terephthalate).
Claim 7
Dependent Claim
17 words
A composition of claim 2 wherein the polycarbonate is an aromatic polycarbonate derived from 2,2 bis(4-hydroxy phenyl)propane.
Claim 8
Dependent Claim
11 words
A composition of claim 2 wherein the polyamide is Nylon 6,6.
Claim 9
Dependent Claim
19 words
A composition of claim 2 wherein the thermoplastic resin (a) is a blend of poly(ethylene terephthalate) and poly(1,4-butylene terephthalate).
Claim 10
Dependent Claim
18 words
A composition of claim 2 wherein the thermoplastic resin (a) is a blend of polycarbonate and poly(1,4-butylene terephthalate).
Claim 11
Dependent Claim
18 words
A composition of claim 2 wherein the thermoplastic resin (a) is a blend of polycarbonate and poly(ethylene terephthalate).
Claim 12
Dependent Claim
12 words
The composition of claim 2 wherein the thermoplastic polymer is polyphenylene ether.
Claim 13
Dependent Claim
39 words
The composition of claim 11 which further comprises a rubber or a rubber modified thermoplastic resin selected from the group consisting of high impact polystyrene, rubber modified alpha-substituted or para-substituted styrene polymers, ethylene-propylene rubber and ethylene propylene-diene monomer rubbers.
Claim 14
Dependent Claim
20 words
The composition of claim 2 wherein the thermoplastic polymer (a) is a blend of polyphenylene ether and high impact polystyrene.
Claim 15
Dependent Claim
15 words
A composition as defined in claim 2 which further comprises a thermoplastic addition polymer resin.
Claim 16
Dependent Claim
33 words
The composition of claim 14 wherein the thermoplastic addition polymer resin is selected from the group consisting of a styrene resin, an alkyl acrylate resin or a mixture of any of the foregoing.
Claim 17
Dependent Claim
14 words
The composition of claim 15 wherein the thermoplastic addition polymer resin is acrylonitrile-butadiene-styrene resin.
Claim 18
Dependent Claim
10 words
The composition of claim 6 which further comprises acrylonitrile-butadiene-stryene resin.
Claim 19
Dependent Claim
29 words
The composition of claim 15 wherein the thermoplastic addition polymer is a graft copolymer selected from the group consisting of core-shell type acrylic elastomers, acrylic copolymers and vinylic copolymers.
Claim 20
Dependent Claim
19 words
The composition of claim 15 wherein the addition polymer is a blend of a graft copolymer and ethylene ethylacrylate.
Claim 21
Dependent Claim
35 words
A composition as defined in claim 2 which further comprises a rubber modified resin selected from the group consisting essentially of high impact polystyrene, rubber modified substituted styrene resins, ethylene-propylene-diene monomer rubbers and ethylene-propylene rubbers.
Claim 22
Dependent Claim
25 words
The composition as defined in claim 1 wherein the metal flake is present in an amount of from about 30 to about 40% by weight.
Claim 23
Dependent Claim
28 words
The composition as defined in claim 1 wherein the metal flake is selected from the group consisting essentially of aluminum flake, nickel flake, copper flake and silver flake.
Claim 24
Dependent Claim
13 words
The composition of claim 22 wherein the flake is Aluminum or aluminum alloy.
Claim 25
Dependent Claim
20 words
The composition of claim 1 wherein the weight ratio of flake to fiber is from about 6:1 to about 10:1.
Claim 26
Dependent Claim
31 words
The composition of claim 1 wherein the metal or metal coated fibers are present in an amount of from about 4 to about 8% by weight based on the total composition.
Claim 27
Dependent Claim
34 words
The composition of claim 1 wherein the metal fibers are selected from the group consisting essentially of aluminum fibers, stainless steel fibers, nickel fibers, silver fibers, copper fibers and fibers prepared from alloys thereof.
Claim 28
Dependent Claim
24 words
The composition of claim 1 wherein the metal coated fibers are selected from the group consisting essentially of metal coated glass and carbon fibers.
Claim 29
Dependent Claim
24 words
The composition of claim 27 wherein the metal coating is selected from the group consisting essentially of nickel, aluminum, silver, copper and alloys thereof.
Claim 30
Dependent Claim
15 words
The composition of claim 27 wherein the metal coated fiber is aluminum coated glass fiber.
Claim 31
Dependent Claim
15 words
The composition of claim 27 wherein the metal coated fiber is nickel coated graphite fiber.
Claim 32
Dependent Claim
19 words
The composition of claim 1 which further comprises from about 3 to about 25% by weight of glass fibers.
Claim 33
Dependent Claim
21 words
The composition as defined in claim 2 which further comprises from about 3 to about 25% by weight of glass fibers.
Claim 34
Dependent Claim
21 words
The composition as defined in claim 14 which further comprises from about 3 to about 25% by weight of glass fibers.
Claim 35
Dependent Claim
21 words
The composition as defined in claim 20 which further comprises from about 3 to about 25% by weight of glass fibers.
Claim 36
Dependent Claim
14 words
The composition of claim 1 which further comprises an effective amount of flame retardant.
Claim 37
Dependent Claim
14 words
The composition of claim 31 which further comprises an effective amount of flame retardant.
Claim 38
Dependent Claim
33 words
The composition of claim 35 wherein the flame retardant is selected from the group consisting essentially of halogenated bisphenol based polycarbonate and phosphorus compounds, either alone or in combination with an antimony compound.
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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) | 1989-01-27 | 1989-07-29 | 1990-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-27 | 1993-07-29 | 1994-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-27 | 1997-07-29 | 1998-01-28 | $7700.00 | Window Closed / Lapsed |