Browse Prior Art Database

High Thermal Conductance Printer Circuit Card

IP.com Disclosure Number: IPCOM000050322D
Original Publication Date: 1982-Oct-01
Included in the Prior Art Database: 2005-Feb-10
Document File: 2 page(s) / 34K

Publishing Venue

IBM

Related People

Aakalu, NG: AUTHOR [+2]

Abstract

This laminated circuit provides good heat dissipation and also extends operating as well as process temperatures to higher limits.

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High Thermal Conductance Printer Circuit Card

This laminated circuit provides good heat dissipation and also extends operating as well as process temperatures to higher limits.

A thermoplastic film bonds the copper conductor lines of a circuit to a metal heat sink plate. The thermoplastic also functions as a dielectric between the copper and the heatsink. The lamination of the conductor layer, thermoplastic film and the metal heatsink are brought about by the use of heat and pressure. The personalization of the top conductive surface may be achieved by two methods: a) Photolith and chemical etch of copper foil after lamination.

b) Punch out from a continuous roll of copper foil the required

circuit pattern, then transfer the punched copper to the

thermoplastic/heatsink, apply pressure, and heat bond

instantaneously.

A solder mask is applied on top of the copper for environment protection. It also functions as a solder dam.

Fig. 1 is an exploded view showing the copper foil 1 and the plastic film 2 which in a later step are heat and pressure bonded to heatsink 3 using nip rollers. As shown in Fig. 2, to improve the dielectric strength between the top circuit and the heatsink plate, the two mating sides can be precoated with the thermoplastic, as shown in 4 and 5, before the lamination process. It may be necessary to dry the thermoplastic before the bonding process to eliminate voids.

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