US 8,617,688 B2 · Conductive paste and multilayer printed wiring board using the same

Abstract

The present invention provides a conductive paste comprising flake conductive fillers having a 99% cumulative particle size of 25 μm or less and a binder resin as essential components. The flake conductive fillers are metal particles having a silver-copper alloy surface layer. The conductive paste according to the present invention is fused with a part of a copper foil circuit to which the conductive paste is to be connected during connection by heating and pressurization, and has high electrical conductivity and high fill ration in a via hole. Thus, the conductive paste according to the present invention provides a multilayer printed wiring board that has high reliability of connection and excellent interlayer connection.

Claims6

Dependent claims

A multilayer printed wiring board having interlayer connection via hole parts and a conductive layer circuit,

wherein the via holes are filled with a conductive paste comprising flake conductive fillers having a 99% cumulative particle size of 25 μm or less and a binder resin as essential components, the flake conductive fillers being metal particles having a silver-copper alloy surface layer,
wherein the conductive paste has a viscosity ratio (η0.5/η2.5) of 0.7 to 2.0,
the flake conductive fillers have an average particle diameter in the range of 1 μm to 4 μm, and
a part of the flake fillers in the conductive paste are fused with a part of the conductive layer circuit.

1 more element

Dependencies are inferred from the claim text.

Facts

Application

11/663,450Filed 18 May 2006

Priority

JP 2005-15669330 May 2005

Published

US 2009/0220738 A13 Sep 2009

Granted

31 Dec 2013

Term ends

Not estimatedThe source records don’t support an estimate.

Classification11 codes

H01B 1/22
Conductive material dispersed in non-conductive organic material: the conductive material comprising metals or alloys
H05K 1/095
Dispersed materials, e.g. conductive pastes or inks: for polymer thick films, i.e. having a permanent organic polymeric binder
H05K 3/4617
The electrical connections between the circuit boards being made during lamination: characterized by laminating only or mainly similar…
H05K 3/4069
By thick-film techniques: for via connections in organic insulating substrates

Conductive paste and multilayer printed wiring board using the same

Life of this patent

Conductive paste and multilayer printed wiring board using the same

Life of this patent

Abstract

Claims6