Abstract: A heat-exchanger fin material (1) has a coating film (3) formed on at least one surface of an aluminum substrate (2). An outermost surface of the coating film (3) is a positively-chargeable coating (31) that is essentially composed of only one or more resins selected from the group consisting of cellulose-based resins, acrylic-based resins, vinyl alcohol-based resins, acrylamide-based resins, and ester-based resins. The surface roughness Ra of the coating film (3) is 100 nm or less. A heat exchanger (5) includes a plurality of fins composed of the fin material (1) and at least one metal tube (7) passing through the plurality of fins (1).

Abstract: A heat exchanger includes a plurality of fins composed a precoated aluminum sheet (1) having a substrate (2) composed of aluminum, and a hydrophilic-coating film (3) formed on at least one surface thereof. The precoated aluminum sheets (1) have a surface roughness RzL of the hydrophilic-coating film (3) in a rolling-parallel direction X of the substrate (2) and a surface roughness RzLT of the hydrophilic-coating film (3) in a rolling-perpendicular direction of the substrate (2). These surface roughnesses satisfy the following relationships: RzL?1.5 ?m, 0.3 ?m?RzLT?2.5 ?m, and RzL/RzLT?0.9. A contact angle ? of a water droplet (19) with respect to the hydrophilic-coating film (3) is 25° or less, and a sliding angle ? of the water droplet (19) in the rolling-parallel direction X is 20° or less.