Patent US4885431A successfully refreshed from Google Patents.
US4885431A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Printed circuit board
Assignee: Nippon CMK Corp
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Filing: 1988-03-29
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Granted: 1989-12-05
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Expires: 2008-03-29
Abstract
Abstract Outer surface of a printed circuit board having circuit conductors on one or both surfaces may be covered by shield film or layer to shield outer noise from reaching the circuit conductors. To shield cross talk and noise from reaching each other, all electrically exposed surfaces of the circuit conductors are covered also by shield film.
Inventors
- 👤 Shin Kawakami
- 👤 Satoshi Haruyama
- 👤 Hirotaka Okonogi
- 👤 Katutomo Nikaido
- 👤 Norito Mukai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:52
CPC Classifications
H; H05; H05K; H05K1/00; H05K1/02; H05K1/0213; H05K1/0216; H05K1/0218; H05K1/0219; H05K1/0221; H05K9/00; H05K9/0007; H05K9/002; H05K9/0039; H05K2201/00; H05K2201/07; H05K2201/0707; H05K2201/0715; H05K2201/09; H05K2201/09209; H05K2201/09654; H05K2201/09809; H05K2201/09818; H05K2201/09981; H05K3/00; H05K3/46; H05K3/4644
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
96 words
A printed circuit board comprising: a base plate having opposed major surfaces; electrically conductive elements formed on at least one major surface of said base plate; an insulating layer formed directly on and covering all electrically exposed surfaces of each respective electrically conductive element; a shield film formed over all exposed surfaces of each respective insulating layer to effectively shield the electrically conductive elements from external electric noise; and another insulating layer formed on and covering all exposed surfaces of the shield films and the exposed surface of said one major surface of said base plate.
Claim 2
Dependent Claim
96 words
A printed circuit board comprising: a base plate having opposed major surfaces; electrically conductive elements formed on at least one major surface of said base plate; an insulating layer formed directly on and covering all electrically exposed surfaces of each respective electrically conductive element; a shield film formed over all exposed surfaces of each respective insulating layer to effectively shield the electrically conductive elements from external electric noise; and another insulating layer formed on and covering all exposed surfaces of the shield films and the exposed surface of said one major surface of said base plate.
Claim 3
Dependent Claim
62 words
A printed circuit board according to claim 1; further comprising electrically conductive elements mounted on the other major surface of said base plate; an insulating layer formed directly on and covering all electrically exposed surfaces of each respective electrically conductive elements formed on the other major surface; and a shield film formed over all exposed surfaces of each respective aforesaid insulating layers.
Claim 4
Dependent Claim
26 words
A printed circuit board according to claim 1; further comprising another shield film formed over said another insulating layer and extending over the first-mentioned shield films.
Claim 5
Dependent Claim
26 words
A printed circuit board according to claim 3; further comprising another insulating layer formed directly on and covering the exposed surface of said another shield film.
Claim 6
Dependent Claim
25 words
A printed circuit board according to claim 1; wherein the electrically conductive elements are formed directly on the one major surface of said base plate.
Claim 7
Dependent Claim
19 words
A printed circuit board according to claim 1; wherein said shield films are composed of a hardened paste material.
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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) | 1992-12-04 | 1993-06-05 | 1993-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-12-04 | 1997-06-05 | 1997-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-12-04 | 2001-06-05 | 2001-12-05 | $7700.00 | Window Closed / Lapsed |