US4882245A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photoresist composition and printed circuit boards and packages made therewith
Assignee: International Business Machines Corp
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Filing: 1987-06-12
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Granted: 1989-11-21
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Expires: 2007-06-12
Abstract
Abstract A photocurable composition which is useful as a permanent resist in the manufacture of printed circuit boards and packages of such boards comprises a multifunctional epoxidized resin, a reactive diluent, a cationic photoinitiator and, optionally, an exposure indicator, a coating aid and a photosensitizer.
Inventors
- 👤 Jeffrey D. Gelorme
- 👤 Robert J. Cox
- 👤 Sergio A. R. Gutierrez
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:21
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/22; H05K3/28; H05K3/285; H05K3/287; G; G03; G03F; G03F7/00; G03F7/004; G03F7/038; G03F7/0385; H05K3/10; H05K3/18; H05K3/181; H05K3/182; H05K3/184; Y; Y10; Y10S; Y10S428/00; Y10S428/901; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24851; Y10T428/24917; Y10T428/26
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
196 words
A printed circuit board comprising a fully cured epoxy-resin-containing substrate, a pattern of conductive material disposed on said substrate, and an imagewise pattern of a fully cured photocurable composition disposed on said substrate; said fully cured photocurable composition resulting from a reaction between a photocurable composition and a cationic photoinitiator; said photocurable composition comprising the product of: (a) a polyepoxyfunctional novolak resin which is curable through the action of said cationic photoinitiator; and (b) a diluent soluble in developing solvents for photoresists and reactive with the epoxy functional groups of said epoxy novolak resin by the action of said cationic photoinitiator to form said fully cured composition insoluble in said developing solvents; wherein said epoxy novolak resin comprises at least approximately 65 weight percent of the resin solids of said photocurable composition, said diluent comprises from approximately 10 to approximately 35 weight percent of said resin solids, and said cationic photoinitiator comprises from approximately 2 to approximately 6 weight percent of said resin solids; said fully curved photocurable composition being at least approximately 0.0015 inch in cross sectional height; and said fully cured photocurable composition being substantially resistant to delamination from said substrate when temperature cycled.
Claim 2
Dependent Claim
196 words
A printed circuit board comprising a fully cured epoxy-resin-containing substrate, a pattern of conductive material disposed on said substrate, and an imagewise pattern of a fully cured photocurable composition disposed on said substrate; said fully cured photocurable composition resulting from a reaction between a photocurable composition and a cationic photoinitiator; said photocurable composition comprising the product of: (a) a polyepoxyfunctional novolak resin which is curable through the action of said cationic photoinitiator; and (b) a diluent soluble in developing solvents for photoresists and reactive with the epoxy functional groups of said epoxy novolak resin by the action of said cationic photoinitiator to form said fully cured composition insoluble in said developing solvents; wherein said epoxy novolak resin comprises at least approximately 65 weight percent of the resin solids of said photocurable composition, said diluent comprises from approximately 10 to approximately 35 weight percent of said resin solids, and said cationic photoinitiator comprises from approximately 2 to approximately 6 weight percent of said resin solids; said fully curved photocurable composition being at least approximately 0.0015 inch in cross sectional height; and said fully cured photocurable composition being substantially resistant to delamination from said substrate when temperature cycled.
Claim 3
Dependent Claim
23 words
A package comprising at least 2 printed circuit boards according to claim 1; said circuit boards having been fully cured in layered contact.
Claim 4
Dependent Claim
13 words
The package of claim 2 which additionally comprises at least one enclosing layer.
Claim 5
Dependent Claim
14 words
The package of claim 3 wherein the enclosing layer includes an epoxy containing resin.
Claim 6
Dependent Claim
22 words
The printed circuit board as in claim 1 wherein said epoxy novolak resin has an average of about eight epoxy functional groups.
Claim 7
Dependent Claim
15 words
The printed circuit board as in claim 5 wherein said diluent is a cycloaliphatic epoxide.
Claim 8
Dependent Claim
15 words
The printed circuit board as in claim 1 wherein said diluent is a cycloaliphatic epoxide.
Claim 9
Dependent Claim
16 words
The printed circuit board as in claim 7 wherein said diluent is 3,4 epoxycyclohexmethyl-3,4 epoxycyclohexyl carboxylate.
Claim 10
Dependent Claim
16 words
The printed circuit board as in claim 6 wherein said diluent is 3,4 epoxycyclohexylmethyl-3,4 epoxycyclohexyl carboxylate.
Claim 11
Dependent Claim
16 words
The printed circuit board as in claim 7 wherein said diluent is 7-oxabicyclo(4.1.0)heptane3-carboxylic acid, 7-xoabicyclo(4.1.0)hept3)ylmethyl ester.
Claim 12
Dependent Claim
16 words
The printed circuit board as in claim 6 wherein said diluent is 7-oxabicyclo(4.1.0)heptane-3-carboxylic acid, 7-oxabicylo(4.1.0)hept-3-ylmethyl ester.
Claim 13
Dependent Claim
20 words
The printed circuit board as in claim 1 wherein said photoinitiator is a triarylsulphonium salt or mixtures of such salts.
Claim 14
Dependent Claim
22 words
The printed circuit board as in claim 12 wherein said photoinitiator is a triarylsulphonium hexafluoro antimonate and thio phenoxy triarylsulphonium hexafluoro antimonate.
Claim 15
Dependent Claim
25 words
The printed circuit board as in claim 1 wherein said epoxy novolak resin comprises approximately 78 to approximately 83 weight percent of said resin solids.
Claim 16
Dependent Claim
24 words
The printed circuit board as in claim 14 wherein said diluent comprises from about 12 to about 17 weight percent of said resin solids.
Claim 17
Dependent Claim
21 words
The printed circuit board as in claim 15 where said cationic photoinitiator comprises about 4 weight percent of said resin solids.
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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) | 1992-11-20 | 1993-05-22 | 1993-11-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-11-20 | 1997-05-22 | 1997-11-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-11-20 | 2001-05-22 | 2001-11-21 | $7700.00 | Window Closed / Lapsed |