Patent US5077136A successfully refreshed from Google Patents.
US5077136A
Expired / Lapsed
US
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Diffusion barrier for solvents and inorganic cations on polyimide surfaces by ammonia treatment
Assignee: Hewlett Packard Development Co LP
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Filing: 1989-09-13
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Granted: 1991-12-31
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Expires: 2009-09-13
Abstract
Abstract A method of inhibiting diffusion into a polyimide body by organic solvents and cations comprising applying ammonia to one or more surfaces of the body prior to exposing the surface to the solvents and cations. A composite article incorporating the diffusion barrier is also disclosed.
Inventors
- 👤 Jieh-Hwa Shyu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:12
CPC Classifications
C; C08; C08J; C08J7/00; C08J7/12; B; B05; B05D; B05D3/00; B05D3/10; B05D3/107; H; H05; H05K; H05K3/00; H05K3/22; C08J2379/00; C08J2379/04; C08J2379/08; H05K2201/00; H05K2201/01; H05K2201/0137; H05K2201/0154; H05K2201/07; H05K2201/0753; H05K2201/0769; H05K2203/00; H05K2203/07; H05K2203/0779; H05K2203/0786; H05K2203/0793; H05K2203/11; H05K2203/1147; Y; Y10; Y10S; Y10S428/00; Y10S428/901; Y10S428/911; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12535; Y10T428/12556; Y10T428/12569; Y10T428/31504; Y10T428/31721
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
41 words
A method of providing a diffusion barrier to a metal-polyimide composite article for protection against organic solvents and inorganic cations comprising the steps of: providing a metal-polyimide composite; applying ammonia to the exposed surfaces of the polyimide component of the composite.
Claim 2
Independent Claim
41 words
A method of providing a diffusion barrier to a metal-polyimide composite article for protection against organic solvents and inorganic cations comprising the steps of: providing a metal-polyimide composite; applying ammonia to the exposed surfaces of the polyimide component of the composite.
Claim 3
Dependent Claim
11 words
The method of claim 1 wherein said ammonia is liquid ammonia.
Claim 4
Dependent Claim
16 words
The method of claim 2 wherein said liquid ammonia is applied to said composite by immersion.
Claim 5
Dependent Claim
15 words
The method of claim 2 wherein said liquid ammonia comprises 15 to 100% ammonium hydroxide.
Claim 6
Dependent Claim
21 words
The method of claim 4 wherein said liquid ammonia is applied to said composite by immersing for at least 5 minutes.
Claim 7
Dependent Claim
21 words
The method of claim 4 wherein, said liquid ammonia is aqueous ammonia comprising ammonium hydroxide from about 15% to about 100%.
Claim 8
Dependent Claim
15 words
The method of claim 5 wherein said ammonium hydroxide is about 20% to about 60%.
Claim 9
Dependent Claim
37 words
An article comprising a polyimide or a metal-polyimide composite and an organic solvent or cation diffusion barrier at one or more surfaces of the polyimide or composite formed by applying ammonia to said one or more surfaces.
Claim 10
Dependent Claim
37 words
An article comprising a polyimide or a metal-polyimide composite and an organic solvent or cation diffusion barrier at one or more surfaces of the polyimide or composite formed by applying ammonia to said one or more surfaces.
Claim 11
Dependent Claim
14 words
The article of claim 8, wherein said polyimide is poly (4, 4' oxydiphenylene pyromellitimide).
Claim 12
Dependent Claim
16 words
The article of claim 8 wherein said composite is a lead frame or a printed circuit.
Claim 13
Dependent Claim
9 words
An article made by the method of claim 6.
Claim 14
Dependent Claim
9 words
An article made by the method of claim 7.
References Cited (Backward Citations)
US4482577A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-12-30 | 1995-07-01 | 1995-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-12-30 | 1999-07-01 | 1999-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-12-30 | 2003-07-01 | 2003-12-31 | $7700.00 | Window Closed / Lapsed |