Electroconductive coating composition, a printed circuit board fabricated by using it and a flexible printed circuit assembly with electromagnetic shield
Abstract
Abstract The invention relates to an electroconductive coating composition with excellent conductivity, adhesion to copper foil and solder dip resistance which is suitable for the formation of a jumper circuit and an electromagnetic shield layer, a printed circuit board fabricated with the above composition, and a durable electromagnetic-shielded flexible printed circuit assembly, wherein said coating composition comprises, by weight, 100 parts of copper metal powder coated with 0.05-0.2 parts of titanate or/and zirconate, 5-30 parts of resole phenolic resin, 0.5-4 parts of a chelating agent, 0.1-5 parts of an adhesion improving agent and 0.5-7 parts of a conductivity improving agent. This composition is less expensive than the silver paste, superior to the latter in the conductivity and adhesion to copper foil of the coating film and in solder dip resistance, thus being suited for the construction of a jumper circuit and an electromagnetic shield layer. It lends itself well to the mounting of IC, MSI, LSI, etc. by dipping in a molten solder bath.
Inventors
- 👤 Hisatoshi Murakami
- 👤 Shinichi Wakita
- 👤 Tsunehiko Terada
- 👤 Shohei Morimoto
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2001-04-06 | 2001-10-06 | 2002-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-04-06 | 2005-10-06 | 2006-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-04-06 | 2009-10-06 | 2010-04-07 | $7700.00 | Window Closed / Lapsed |