Method of forming a thin film on the surface of a substrate using a roll coater

A method for utilizing an applicator roll to form a coating of film having a thickness on an upper surface of a substrate having a rear edge by applying coating liquid on the surface of said substrate, said method comprising the steps of:

• (a) supplying said coating liquid on a circumferential surface of said applicator roll;
• (b) transporting said substrate relative to said applicator roll while continuously contacting the circumferential surface of said applicator roll with the upper surface of said substrate, from a start position at which said contact is started, to an end position at which said contact is terminated, for transferring coating liquid supplied on the circumferential surface of said applicator roll to the surface of said substrate;
• (c) rotating said applicator roll in a direction so that the circumferential surface of said applicator roll moves opposite to a direction along which the surface of said substrate is transported at a position in which the circumferential surface of said applicator roll is contacted with the surface of said substrate;
• (d) rotating said applicator roll at a speed of rotation while contacting the circumferential surface of said applicator roll with the surface of said substrate, for transferring coating liquid supplied to the circumferential surface of said applicator roll to the surface of said substrate;
• and
• (e) reducing the rotational speed of said applicator roll before said substrate is transported to said end position relative to the rotational speed when said substrate is at said start position, for reducing an amount of said coating liquid transferred from the circumferential surface of said applicator roll to the surface of said substrate before said substrate is transported to said end position, relative to an amount of said coating liquid transferred from the circumferential surface of said applicator roll to the surface of said substrate when said substrate is at said start position.

A method for utilizing an applicator roll to form a coating of film having a thickness on a surface of a substrate having a rear edge by applying coating liquid on the surface of said substrate, said method comprising the steps of:

• (a) supplying said coating liquid on a circumferential surface of said applicator roll;
• (b) rotating said applicator roll such that said circumferential surface of said applicator roll moves in a first direction;
• (c) contacting said substrate with said circumferential surface at a start position;
• (d) transporting said substrate in a second direction opposite to said first direction of said circumferential surface of said applicator roll at said start position while continuously contacting the circumferential surface of said applicator roll with the surface of said substrate, from said start position at which said contact is started, to an end position at which said contact is terminated, for transferring coating liquid supplied on the circumferential surface of said applicator roll to the surface of said substrate;
• and
• (e) reducing an amount of coating liquid to be transferred to the surface of said applicator roll before said substrate is transported to said end position relative to an amount transferred to the surface of said applicator roll when said substrate is at said start position for reducing an amount of said coating liquid transferred from the circumferential surface of said applicator roll to the surface of said substrate before said substrate is transported to said end position, relative to an amount of said coating liquid transferred from the circumferential surface of said applicator roll to the surface of said substrate when said substrate is at said start position.