Evaporator and loop-type heat pipe using the same

An evaporator comprising:

• a container having an inner surface;
• a laminated porous wick including at least first and second laminated wick portions, said wick having a thickness and pores, the pores having diameters that vary with position through the thickness of said wick, wherein said second wick portion is outside said first portion, has an outer surface in contact with said inner surface of said container, and is expanded polytetrafluoroethylene, and said first wick portion has an inner wall surface and is a porous ceramic having a greater rigidity than said second wick portion;
• a sump defined by the inner wall surface of said first wick portion, said sump being connected to a liquid pipe for supplying a working fluid in a liquid phase;
• and
• a vapor channel disposed between said container and said second wick portion, said vapor channel providing fluid communication between said wick and a vapor pipe, said vapor pipe guiding the working fluid in a gas phase and being connected to an end portion of said container.