| 摘要 |
PURPOSE:To increase the hydrophilic nature on the surface of an evaporator made of Al and to prevent the driving-out of condensate, by subjecting the surface of said evaporator to a chromate treatment then forming a silicate film thereon. CONSTITUTION:A film of chromic acid chromate or phosphoric acid chromate is formed on the surface of an evaporator 1 made of Al to be used for a refrigeration cycle to improve the corrosion resistance thereof, whereafter the evaporator is dipped in an aq. silicate soln. consisting essentially of 25-30wt% SiO2 and 5-20wt% Na2O to form the silicate film and to improve the hydrophilic nature on the surface. the moisture in the air passing through the evaporator 1 under use as a cooler is cooled and condensed and the condensate sticks on the flat tubes 2 and fins 3 of the evaporator. Since the stuck water has high hydrophilic nature to the surface thereof, the contact angle theta to the surface is small and the driving-out of the water by the air flow is obviated. |
