Patent US4421608A successfully refreshed from Google Patents.
US4421608A
Expired / Lapsed
US
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Method for stripping peel apart conductive structures
Assignee: International Business Machines Corp
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Filing: 1982-03-01
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Granted: 1983-12-20
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Expires: 2002-03-01
Abstract
Abstract A fluid is applied between the carrier member and the conductive member of a peel apart structure during the peel apart operation between the carrier member and the conductive member. The fluid reduces the bonding strength between the carrier member and the conductive member and thus maintains the integrity of the conductive member as the carrier member is peeled away.
Inventors
- 👤 Donald G. McBride
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:48
CPC Classifications
H; H05; H05K; H05K3/00; B; B29; B29C; B29C63/00; B29C63/0004; B29C63/0013; H05K3/02; H05K3/022; H05K3/025; H05K2203/00; H05K2203/01; H05K2203/0147; H05K2203/0152; H05K2203/07; H05K2203/0703; H05K2203/0726; H05K2203/0779; H05K2203/0786; Y; Y10; Y10T; Y10T156/00; Y10T156/11; Y10T156/1111
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
111 words
A method for stripping a peel apart structure, said peel apart structure having an electrolytic plated copper first layer in a predetermined superimposed and peelably adhered relationship with an electrolytic copper foil carrier second layer, said first and second layers having an average bond strength therebetween of approximately two to four psi, said method comprising the steps of: providing water for reducing said average bond strength between said first and second layers approximately thirty to forty percent, mechanically peeling apart said first and second layers, and applying said water in a chemically inert manner between said first and second layers during the peel apart operation between said first and second layers.
Claim 2
Independent Claim
111 words
A method for stripping a peel apart structure, said peel apart structure having an electrolytic plated copper first layer in a predetermined superimposed and peelably adhered relationship with an electrolytic copper foil carrier second layer, said first and second layers having an average bond strength therebetween of approximately two to four psi, said method comprising the steps of: providing water for reducing said average bond strength between said first and second layers approximately thirty to forty percent, mechanically peeling apart said first and second layers, and applying said water in a chemically inert manner between said first and second layers during the peel apart operation between said first and second layers.
Claim 3
Dependent Claim
12 words
The method according to claim 1 wherein said water is deionized water.
Claim 4
Dependent Claim
24 words
The method according to claim 1 wherein said peel apart structure further has release agent member means disposed between said first and second layers.
Claim 5
Dependent Claim
14 words
The method according to claim 3 wherein said release agent member means is chromium.
Claim 6
Dependent Claim
154 words
In a method for making printed circuit boards, said method using at least one peel apart conductive flexible planar sheet structure having an electrolytic plated copper first layer in a predetermined superimposed and peelably adhered relationship with an electrolytic copper foil carrier second layer, said first and second layers having an average bond strength therebetween of approximately two to four psi, and a metal release agent third layer disposed between said first and second layers, said first and second layers having an average bond strength therebetween of approximately two to four psi, said method further including a step for mechanically peeling said second layer from said first layer, the combination therewith comprising the steps of: providing deionized water for reducing said bond strength between said first and second layers approximately thirty to forty percent, and applying said deionized water in a chemically inert manner between said first and second layers during said peeling step.
Claim 7
Dependent Claim
154 words
In a method for making printed circuit boards, said method using at least one peel apart conductive flexible planar sheet structure having an electrolytic plated copper first layer in a predetermined superimposed and peelably adhered relationship with an electrolytic copper foil carrier second layer, said first and second layers having an average bond strength therebetween of approximately two to four psi, and a metal release agent third layer disposed between said first and second layers, said first and second layers having an average bond strength therebetween of approximately two to four psi, said method further including a step for mechanically peeling said second layer from said first layer, the combination therewith comprising the steps of: providing deionized water for reducing said bond strength between said first and second layers approximately thirty to forty percent, and applying said deionized water in a chemically inert manner between said first and second layers during said peeling step.
Claim 8
Dependent Claim
15 words
The method according to claim 5 wherein said first layer is approximately 0.0002 inches thick.
Claim 9
Dependent Claim
24 words
The method according to claim 6 wherein said second layer is approximately 0.0028 inches thick, and said third layer has a relative negligible thickness.
Claim 10
Dependent Claim
12 words
The method according to claim 5 wherein said third layer is chromium.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-19 | 1987-06-20 | 1987-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-19 | 1991-06-20 | 1991-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-19 | 1995-06-20 | 1995-12-20 | $7700.00 | Window Closed / Lapsed |