Coating die, coating device, coating method, and method for manufacturing secondary cell

1. A coating die comprising:

a first block including a first manifold to receive a first coating liquid;

a second block including a second manifold to receive a second coating liquid; and

a shim sandwiched between the first block and the second block,

the shim including recesses disposed only on the shim, the recesses including:

a first recess on a face of the shim facing the first block, the first recess communicating with the manifold, and

a second recess on a face of the shim facing the second block, the second recess communicating with the second manifold,

the first recess having one end in a direction orthogonal to a stacking direction of the first block, the shim and the second block and orthogonal to a longitudinal direction of the shim, the one end being open to define a first discharge slot to discharge the first coating liquid,

the second recess having one end in the direction of the one end of the first recess, the one end of the second recess being open to define a second discharge slot to discharge the second coating liquid, wherein the second coating liquid stacks at least partially with the first coating liquid, wherein the second recess and the first recess are disposed on mutually opposite sides relative to the shim

wherein the shim includes a plurality of projections on the first recess, the projections having a height that is a substantially same dimension as a depth of the first recess, and/or a plurality of projections on the second recess, the projections having a height that is a substantially same dimension as a depth of the second recess.

2. The coating die according to claim 1 , wherein the plurality of projections on at least one of the first recess and the second recess are arranged in a line along the longitudinal direction.

3. The coating die according to claim 1 , wherein the first coating liquid and the second coating liquid with mutually different pressures are supplied to the first manifold and the second manifold, respectively, and the plurality of projections on at least one of the first recess and the second recess is on the first recess or the second recess where the coating liquid with a lower pressure between the first coating liquid and the second coating liquid travels.

4. The coating die according to claim 1 , wherein the shim includes the plurality of projections on the first recess and the plurality of projections on the second recess, the plurality of projections on the first recess and the plurality of projections on the second recess being disposed on a same position viewed from the stacking direction.

5. The coating die according to claim 1 , wherein the second discharge slot has a length in the longitudinal direction that is shorter than a length of the first discharge slot in the longitudinal direction and the first discharge slot covers entirely the second discharge slot in the longitudinal direction.

6. The coating die according to claim 2 , wherein the first coating liquid and the second coating liquid with mutually different pressures are supplied to the first manifold and the second manifold, respectively, and the plurality of projections on at least one of the first recess and the second recess is on the first recess or the second recess where the coating liquid with a lower pressure between the first coating liquid and the second coating liquid travels.

7. The coating die according to claim 2 , wherein the shim includes the plurality of projections on the first recess and the plurality of projections on the second recess, the plurality of projections on the first recess and the plurality of projections on the second recess being disposed on a same position viewed from the stacking direction.