▎ 摘　　要

NOVELTY - The printed wiring board (10) has first printed wiring board layer (32) having an upper surface for attaching electrical components and a lower surface. A second printed wiring board layer (22) having upper and lower surfaces. A thermal core material is inserted between the lower surface of the first printed wiring board and the upper surface of the second printed wiring board. The thermal core material includes first and second planar graphene sheets thermo-mechanically bonded by a metal alloy layer formed from planar layers. USE - Printed wiring board. ADVANTAGE - Since the expansion and contraction of the layers of printed wiring board will be more closely matched, the printed wiring board will experience lower thermo-mechanical stresses as well as less board warpage and distortion at elevated operating temperatures. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a heat spreader for a printed wiring board. DESCRIPTION OF DRAWING(S) - The drawing shows the printed wiring board. Printed wiring board (10) Heat spreading thermal core (14) Second printed wiring board layer (22) Bonding layers (30) First printed wiring board layer (32)