US4678716A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electromagnetic shielding
Assignee: Parker Intangibles LLC
•
Filing: 1985-08-06
•
Granted: 1987-07-07
•
Expires: 2005-08-06
Abstract
Abstract Aluminum silicon alloys are used as cores for highly conductive metal coated particles to be incorporated in resins for use as electromagnetic interference shielding. High temperature processing conditions are used after coating of the particles to improve internal and external corrosion resistance of gaskets and filled resins into which the particles are incorporated for shielding use.
Inventors
- 👤 Wen-Shian V. Tzeng
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:29
CPC Classifications
H; H05; H05K; H05K9/00; H05K9/0073; H05K9/0081; H05K9/0083; B; B22; B22F; B22F1/00; B22F1/17; B29; B29C; B29C70/00; B29C70/88; B29C70/882; H01; H01B; H01B1/00; H01B1/02; H01B1/20; H01B1/22; H01P; H01P1/00; H01P1/04; H01P1/042; H05K9/0007; H05K9/0015; B29K; B29K2995/00; B29K2995/0003; B29K2995/0005; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12014; Y10T428/12028; Y10T428/12049; Y10T428/12493; Y10T428/12674; Y10T428/12708; Y10T428/12715; Y10T428/12722; Y10T428/12736; Y10T428/12743; Y10T428/1275
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
74 words
An electrically conductive particle for use as a conductive filler in a resin matrix suitable for electromagnetic shielding use, said particle comprising an inner core of an aluminum silicon alloy having from 5 to 20 percent by weight of silicon, an intermediate layer of a metal selected from the group consisting of mercury, palladium, copper, chromium, platinum, gold, nickel, tin, zinc and mixtures thereof, and an outer layer of a highly electrically conductive metal.
Claim 2
Dependent Claim
74 words
An electrically conductive particle for use as a conductive filler in a resin matrix suitable for electromagnetic shielding use, said particle comprising an inner core of an aluminum silicon alloy having from 5 to 20 percent by weight of silicon, an intermediate layer of a metal selected from the group consisting of mercury, palladium, copper, chromium, platinum, gold, nickel, tin, zinc and mixtures thereof, and an outer layer of a highly electrically conductive metal.
Claim 3
Dependent Claim
18 words
A particle in accordance with claim 1 and further comprising said aluminum silicon alloy being an eutectic alloy.
Claim 4
Dependent Claim
36 words
An electrically conductive particle in accordance with claim 1 and further comprising said last mentioned highly electrically conductive metal being silver in an amount of from 4 percent to 25 percent by weight of said particle.
Claim 5
Dependent Claim
25 words
An electrically conductive particle in accordance with claim 1 wherein said intermediate layer comprises from 0.1 percent to 5 percent by weight of said particle.
Claim 6
Dependent Claim
15 words
An electrically conductive particle in accordance with claim 4 wherein said intermediate layer is zinc.
Claim 7
Dependent Claim
15 words
An electrically conductive particle in accordance with claim 3 wherein said intermediate layer is tin.
Claim 8
Dependent Claim
15 words
An electrically conductive particle in accordance with claim 1 wherein said intermediate layer is zinc.
Claim 9
Dependent Claim
72 words
An electromagnetic energy shielding material having a volume resistivity to be effective as an electromagnetic energy shield, said material comprising resin matrix loaded with electrically conductive particles, said particles comprising an aluminum silicon alloy core having a first layer of a material selected from the group consisting of mercury, palladium, copper, chromium, platinum, gold, nickel, tin and zinc, and an outer layer of a highly electrically conductive metal overlying said first layer.
Claim 10
Dependent Claim
72 words
An electromagnetic energy shielding material having a volume resistivity to be effective as an electromagnetic energy shield, said material comprising resin matrix loaded with electrically conductive particles, said particles comprising an aluminum silicon alloy core having a first layer of a material selected from the group consisting of mercury, palladium, copper, chromium, platinum, gold, nickel, tin and zinc, and an outer layer of a highly electrically conductive metal overlying said first layer.
Claim 11
Dependent Claim
36 words
The shielding material in accordance with claim 8 whereas said particles have an intermediate layer of a metal selected from the group consisting of mercury, palatium, copper, chromium, platinum, gold, nickel, tin, zinc and mixtures thereof.
Claim 12
Dependent Claim
13 words
Shielding material in accordance with claim 9 whereas said intermediate layer is zinc.
Claim 13
Dependent Claim
14 words
A shielding material in accordance with claim 9 whereas said intermediate layer is tin.
Claim 14
Dependent Claim
14 words
A shielding material in accordance with claim 9 whereas said intermedite layer is nickel.
Claim 15
Dependent Claim
14 words
A shielding material in accordance with claim 8 whereas said outer layer is silver.
Claim 16
Dependent Claim
31 words
A shielding material in accordance with claim 13 wherein said outer layer is silver in an amount of from about 4 percent to about 25 percent by weight of said particle.
Claim 17
Dependent Claim
37 words
A shielding material in accordance with claim 8 wherein said aluminum silicon alloy has from about 70 to about 95 percent by weight of aluminum and from about 5 to about 20 percent by weight of silicon.
Claim 18
Dependent Claim
29 words
A shielding material in accordance with claim 15 wherein said silicon is present in an amount of from 9 to 14 percent and said alloy is an eutectic alloy.
Claim 19
Dependent Claim
33 words
A shielding material in accordance with claim 16 comprising from about 80 to about 50 percent by volume of resin and from about 20 to about 50 percent by volume of said particles.
Claim 20
Dependent Claim
67 words
A shielding material in accordance with claim 17 wherein said particles have an average particle size of from about 20 to 75 microns, said intermediate layer is present in an amount of from 0.2 to about 10 percent by weight of said particle and said electrically conductive outer layer is present in an amount of from about 4 to about 25 percent by weight of said particle.
References Cited (Backward Citations)
US4126287A
Cited
US4076652A
Cited
US4189618A
Cited
US4174419A
Cited
US4316944A
Cited
US4434541A
Cited
US4507359A
Cited
US4442182A
Cited
US4587039A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-07-06 | 1991-01-05 | 1991-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-06 | 1995-01-05 | 1995-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-06 | 1999-01-05 | 1999-07-07 | $7700.00 | Window Closed / Lapsed |