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US4243474A Expired / Lapsed US ⏱️ 0.0 years remaining

Process of producing a printed wiring board

Assignee: Shirai Denshi Kogyo Co Ltd
•
Filing: 1979-03-26
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Granted: 1981-01-06
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Expires: 1999-03-26
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Abstract

Abstract This invention relates to a process of producing a printed wiring board having first and second electrically conductive circuit layers provided on an insulating laminate. The insulating laminate includes a first insulating layer having metal foils provided on both sides thereof and a second insulating layer which is attached to one of the sides of the first insulating layer so as to place one of the electrically conductive circuit layers between the first and second insulating layers. The first electrically conductive circuit layer is formed in a predetermined pattern by printing and etching one of the metal foils. Then, connecting through-holes are formed in the first insulating layer across the first electrically conductive circuit layer and the remaining metal foil. The second insulating layer is attached onto the first insulating layer so that the first electrically conductive circuit layer is covered with the second insulating layer. Thereafter the second electrically conductive circuit layer is formed in a predetermined pattern from the remaining metal foil by printing and etching.

Inventors

  • 👤 Haruo Shirai
  • 👤 Yoshikatsu Tanaka
  • 👤 Zinzo Kosuga
  • 👤 Kiyoshi Osaka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 06:26
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/22; H05K3/28; H05K3/0058; H05K3/0064; H05K3/0094; H05K1/00; H05K1/02; H05K1/03; H05K1/0393; H05K2201/00; H05K2201/03; H05K2201/0302; H05K2201/0305; H05K2201/09; H05K2201/09209; H05K2201/095; H05K2201/09536; H05K2201/0959; H05K2203/00; H05K2203/06; H05K2203/068; H05K3/40; H05K3/4038; H05K3/42; H05K3/425; H05K3/427; H05K3/428; Y; Y10; Y10S; Y10S428/00; Y10S428/902; Y10T; Y10T156/00; Y10T156/10; Y10T156/1052; Y10T156/1056; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/49155; Y10T29/49156

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 164 words
A process of producing a printed wiring board having two electrically conductive circuit layers provided on an insulating laminate, said process comprising the steps of; preparing a first insulating layer having a metal foil provided on each side of said first insulating layer; forming a first electrically conductive circuit layer of predetermined pattern by treating one of said metal foils by printing and etching; forming connecting through-holes in said first insulating layer for connecting said first electrically conductive circuit layer and the other metal foil to each other; providing an electrically conductive member in said connecting through-holes so as to connect said first electrically conductive circuit layer and said other metal foil; attaching a second insulating layer by heat and pressure to said first insulating layer so as to cover said first electrically conductive circuit layer whereby said insulating laminate is formed; and thereafter forming a second electrically conductive circuit layer of predetermined pattern by treating said other metal foil by printing and etching.
Claim 2
Dependent Claim 164 words
A process of producing a printed wiring board having two electrically conductive circuit layers provided on an insulating laminate, said process comprising the steps of; preparing a first insulating layer having a metal foil provided on each side of said first insulating layer; forming a first electrically conductive circuit layer of predetermined pattern by treating one of said metal foils by printing and etching; forming connecting through-holes in said first insulating layer for connecting said first electrically conductive circuit layer and the other metal foil to each other; providing an electrically conductive member in said connecting through-holes so as to connect said first electrically conductive circuit layer and said other metal foil; attaching a second insulating layer by heat and pressure to said first insulating layer so as to cover said first electrically conductive circuit layer whereby said insulating laminate is formed; and thereafter forming a second electrically conductive circuit layer of predetermined pattern by treating said other metal foil by printing and etching.
Claim 3
Dependent Claim 43 words
A process of producing a printed wiring board as set forth in claim 1, and wherein said step of providing an electrically conductive member in said connecting through-holes is accomplished by applying an electroless metal plating layer on the wall of said through-holes.
Claim 4
Dependent Claim 42 words
A process of producing a printed wiring board as set forth in claim 2, and wherein said step of providing an electrically conductive member in said connecting throughholes further includes applying an electrical metal plating layer on said electroless metal plating layer.
Claim 5
Dependent Claim 37 words
A process of producing a printed wiring board as set forth in claim 1, and wherein said step of providing an electrically conductive member is accomplished by forcing a melted solder into said connecting through-holes by rolling.
Claim 6
Dependent Claim 43 words
A process of producing a printed wiring board as set forth in claim 1, and wherein said step of providing an electrically conductive member in said connecting through-holes is accomplished by forcing an electrically conductive paint into said connecting through-holes by screen printing.
Claim 7
Dependent Claim 53 words
A process of producing a printed wiring board as set forth in claim 1, and wherein said step of attaching a second insulating layer to said first insulating layer is accomplished by heating and pressurizing a multi-ply thermosetting resin impregnated sheet material as said second insulating layer together with said first insulating layer.
Claim 8
Dependent Claim 57 words
A process of producing a printed wiring board as set forth in claim 1, and wherein said step of attaching a second insulating layer to said first insulating layer is accomplished by heating and pressurizing a multi-ply thermosetting resin impregnated sheet material as said second insulating layer together with a plastic film as said first insulating layer.
Claim 9
Dependent Claim 40 words
A process of producing a printed wiring board as set forth in claim 1, wherein the step of heat and pressure attaching of said first and second insulating layers fills the through-holes with insulating material of the second insulating layer.
Claim 10
Dependent Claim 32 words
A process of producing a printed wiring board as set forth in claim 1, wherein the electrically conductive member in said through-holes is in the range of fifteen to twenty-five microns thickness.
Claim 11
Dependent Claim 29 words
A process of producing a printed wiring board as set forth in claim 1, including the subsequent step of producing second through-holes through the first and second insulating layers.

References Cited (Backward Citations)

US3436819A Cited
US3471631A Cited
US3566005A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-01-06 1984-07-07 1985-01-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-01-06 1988-07-07 1989-01-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-01-06 1992-07-07 1993-01-06 $7700.00 Window Closed / Lapsed

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