COATER

PURPOSE:To eliminate the slight change of a back roll by a temp. change and the film shrinkage and to maintain the uniformity of a coated film by providing a heat medium flow passage to the inside of a backup roll of a coater. CONSTITUTION:The coater for coating a coating liquid on a film consists of the back roll 1 and a metering device 2 and an inside pipe 6 is provided to the inside of the back roll 1 to constitute a double-pipe type. The space of the double pipe part constitutes the spiral heat medium flow passage 8 and the heat medium of specified temp. is passed in the passage 8. The film 4 is passed in the spacing H between the back roll 1 and a coating liquid discharge port 3. The coating liquid 5 from a coating liquid discharge port 3 is coated on the surface of the film 4. Then the slight change of the back roll by the temp. change is eliminated and the shrinkage of the film is eliminated. The uniformity of the coated film is thereby maintained.