Lightweight heat sinks and LED lamps employing same

A heat sink comprising:

• a heat sink body and heat radiating fins, said fins including a first edge engaging said body and a remote second edge, side walls extending between said first edge and said second edge, said body and fins being comprised of a plastic;
• and
• a thermally conductive layer disposed over at least the side walls of said heat sink fins, said thermally conductive layer extending between said first edge and said second edge, wherein the thermally conductive layer has a thermal sheet conductance of at least 0.0025 W/K.

A heat sink comprising:

• a heat sink body and heat radiating fins, said fins including a first edge engaging said body and a remote second edge, side walls extending between said first edge and said second edge, said body and fins being comprised of a plastic;
• and
• a thermally conductive layer disposed over at least the side walls of said heat sink fins, said thermally conductive layer extending between said first edge and said second edge, said heat sink further comprising a polymeric layer disposed between the fins and the thermally conductive layer and extending between the first edge and the second edge.

A heat sink comprising:

• a heat sink body and heat radiating fins, said fins including a first edge engaging said body and a remote second edge, side walls extending between said first edge and said second edge, said body and fins being comprised of a plastic;
• and
• a thermally conductive layer disposed over at least the side walls of said heat sink fins, said thermally conductive layer extending between said first edge and said second edge, wherein the fins are thermally insulating.

A heat sink comprising:

• a heat sink body and heat radiating fins, said fins including a first edge engaging said body and a remote second edge, side walls extending between said first edge and said second edge, said body and fins being comprised of a plastic;
• and
• a thermally conductive layer disposed over at least the side walls of said heat sink fins, said thermally conductive layer extending between said first edge and said second edge, wherein the heat sink body includes passages that are coated by the thermally conductive layer disposed over the heat sink body to define thermal shunting paths.

A light emitting diode (LED)-based lamp comprising a heat sink having a heat sink body and heat radiating fins, said fins including a first edge engaging said body and a remote second edge, side walls extending between said first edge and said second edge, said body and fins being comprised of a plastic;

• a thermally conductive layer disposed over at least the side walls of said heat sink fins, said thermally conductive layer extending between said first edge and said second edge and wherein the thermally conductive layer has a thickness of 500 micron or less and a thermal conductivity of 50 W/m·K or higher;
• and:
• an LED module including one or more LED devices, the LED module secured with and in thermal communication with the heat sink such that the fins are in optical communication with said LED module.