METHOD FOR COATING INNER SURFACE OF CAN

• Main Authors: KUSUBASHI, Ryosuke, OGIWARA, Sho, YAGUCHI, Naoyuki
• Format: Patent
• Language: English; French; German
• Published: 05.08.2020
• Subjects: APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL; PERFORMING OPERATIONS; PROCESSES FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TOSURFACES, IN GENERAL; SPRAYING OR ATOMISING IN GENERAL; TRANSPORTING

The purpose of the present invention is to form a coating film on the entire inner surface of a bottomed cylindrical body while increasing machining resistance of an opening part of the bottomed cylindrical body as less cost. A method according to the present invention comprises: an opening part coating step S1 for spraying an inner area of an opening part of a bottomed cylindrical body with a first coating material while placing the bottomed cylindrical body in a horizontal position and rotating the bottomed cylindrical body around an central axis thereof; a barrel part coating step S3 for spraying, after the opening part coating step S1, an inner area of a barrel part of the bottomed cylindrical body with a second coating material while keeping the horizontal position and rotation around the central axis of the bottomed cylindrical body; and a vaporizing step S4 for stopping, after the barrel part coating step S3 and before the volatile components of the second coating material sprayed onto the inner area of the barrel part of the bottomed cylindrical body vaporizes, the rotation of the bottomed cylindrical body around the central axis, replacing the bottomed cylindrical body from the horizontal position to a vertical position, and vaporizing volatile components of the second coating material. A coating material containing a hardly-sagging synthetic resin which contains higher proportion of non-volatile components is used as the first coating material, and a coating material containing an easily-sagging synthetic resin which contains lower proportion of non-volatile components than that of the first coating material is used as the second coating material.