A foldable heat radiation board includes a plurality of elongated and narrow
plate-like
members with fluid tube embedding grooves provided therein, and the plate-like
members are combined with each other in a quadrangular plan configuration. Fluid
tubes are embedded in the embedding grooves, and a heat radiation sheet is attached
to the entire surface on the front surface side, while a back surface material
is attached to the entire or partial surface on the back surface side. A plurality
of contact portions in which the end portions of adjacent plate-like members contact
each other are set as folding portions, and a fluid tube outlet opening portion
in the end portion of one of the plate-like members and a fluid tube inlet opening
portion in the end portion of the other of the plate-like members are provided
so as not to oppose each other but to be shifted from each other, this portion
being set as a fluid tube passage portion.
