Cooling apparatus boiling and condensing refrigerant

A cooling apparatus boiling and condensing refrigerant for cooling heat a heating-generating member, said cooling apparatus comprising:

• a refrigerant container which stores liquid refrigerant therein and a part of the liquid refrigerant is boiled and vaporized by absorbing heat from the heat-generating member which is attached on a first outer surface of the refrigerant container, the first outer surface being disposed in an almost upright position;
• and
• a radiator, which is disposed onto an opposite outer surface of the refrigerant container, heat exchanges between refrigerant in the radiator and outside fluid passing through said radiator;
• wherein:
• the refrigerant container has a first passage through which refrigerant vaporized by absorbing heat from the heat-generating member passes;
• a second passage through which refrigerant cooled in the radiator and circulates from the radiator passes;
• and
• a partitioning member which partitions a part of the refrigerant container into the first passage and second passage;
• and
• wherein the partitioning member has a heat insulating structure and has a surface substantially parallel to the first outer surface onto which the heat-generating member is attached.