Patent ID: 7976687

Claim:
A roll unit to be dipped in a surface treatment liquid of a copper foil, comprising: a bearing box for housing a roll shaft configured from two divisible bearing boxes, one of the bearing boxes being configured from a roll-side bearing box arranged on a roll main body-side and the other bearing box being configured from a shaft end-side bearing box arranged on the shaft end-side of the roll; the roll-side bearing box having a shaft sleeve covering an outer periphery of the roll shaft and an oil seal provided along an outer periphery of the shaft sleeve; and the shaft end-side bearing box having a bearing for rotatably supporting the shaft, wherein the roll-side bearing box has an oil seal consisting of an inner ring and a spring, wherein an O-ring for inhibiting infiltration of the surface treatment liquid is provided between an inner peripheral face of the shaft sleeve covering the outer periphery of the roll shaft and an outer peripheral face of the shaft, and wherein a lateral face on the roll main body-side of the shaft sleeve is in contact with the roll main body and rotates integrally with the roll shaft.