Abstract: A stack type evaporator includes tubular elements 1 each having a plurality of inwardly protruding recessed ribs 7 which extend from an upper header portion 1a of the element to a lower header portion 1b, with the ribs serving as straight drainage canals 7a of specified width and area. A hydrophilic resin coating of a specific composition covers the outer surfaces of the tubular elements 1 and fins 2 each interposed between two adjacent tubular elements. The combination of straight drainage canals, the specified width and area thereof and the specific hydrophilic resin coating is effective to facilitate the drainage of condensed water so that the waterdrop is substantially prevented from flying out of the evaporator, and the hydrophilic coating itself does not emit any unpleasant smell.

Abstract: A carbon cluster film has a precisely controlled stable electrical conductivity which does not deteriorate in a short period of time in air. Such a carbon cluster film having a stable electrical conductivity is formed by introducing an impurity into a thin film of fullerenes by ion implantation. The fullerenes include C.sub.60, C.sub.70 or the like.

Abstract: A stack type evaporator according to the invention comprises a plurality of plate-shaped tubular elements stacked in a direction of their width with a fin member interposed between two of such tubular elements which have inlet header portions at their ends and outlet header portions at their further ends so that coolant can flow straight within said tubular elements, a pair of dish-shaped core plates which constitute each tubular element having inner surfaces provided with ribs arranged at regular intervals in a direction of coolant flow, wherein an end surface of each rib protruding from one core plate is alternately bonded to a flat body of the other core plate whereby the coolant paths within each tubular element are formed parallel with each other and straight from the inlet header portion toward the outlet header portion.