Film forming method and film forming apparatus

1 . A film forming method for forming a film on a target coating material, the method comprising:

coating a target coating material, to form the film, by discharging liquid intermittently at constant intervals from a plurality of discharge heads that are arranged in a conveyance direction of the target coating material to be conveyed, the plurality of discharge heads discharging the liquid sequentially in an order of the plurality of discharge heads arranged in the conveyance direction, an area of a region of the target coating material where each of the plurality of discharge heads discharge the liquid is equal in size,

wherein one head of the plurality of discharge heads applies ink to form a first linear region in a direction perpendicular to the conveyance direction in the film,

wherein another head, different from the one head, of the plurality of discharge heads applies the ink to form a second linear region perpendicular to the conveyance direction in the film, the second linear region located at a different position on the target coating material in the conveyance direction from the first linear region,

wherein the target coating material includes a current collector with an active material layer formed on the current collector, the active material layer having particles as a main component, and the film as a layer is disposed on the active material layer,

wherein a first discharge head and a second discharge head are included among the plurality of discharge heads, the second discharge head being provided downstream with respect to the first discharge head in the conveyance direction,

wherein the second discharge head applies liquid onto the target coating material 0.3 seconds or more after a point in time at which the first discharge head applies liquid onto the target coating material, resulting in generation of two neighboring ink droplets that have impacted the target coating material in the conveyance direction of the target coating material,

wherein the current collector is a non-permeable substrate, and

wherein a distance between centers of the two neighboring ink droplets is greater than a value obtained by multiplying a conveyance speed of the target coating material by 0.3 sec.

2 . The film forming method according to claim 1 , wherein areas of the target coating material in which the liquid discharged from each of the plurality of discharge heads is applied are substantially uniform.

3 . The film forming method according to claim 1 , wherein the closer a discharge head is, among the plurality of discharge heads, to a downstream side in the conveyance direction, the greater a discharged droplet is in size.

4 . The film forming method according to claim 1 , the liquid discharged contains metal oxide particles at a content of greater than or equal to 30% per unit volume, the liquid being discharged on the active material layer having the particles as the main component, the layer being provided on a non-permeable substrate of the target coating material.

5 . The film forming method according to claim 1 , wherein each of the plurality of discharge heads include a plurality of nozzles arranged in a direction intersecting the conveyance direction, the nozzles discharging the liquid.

6 . The film forming method according to claim 1 , wherein the target coating material includes an electrode, and

wherein, the liquid discharged from each of the plurality of discharge heads is applied to a different location on the electrode in the conveyance direction.

7 . The film forming method according to claim 1 , wherein the first linear region is formed along an entire width of the target coating material in the direction perpendicular to the conveyance direction; and

the second linear region is formed along the entire width of the target coating material in the direction perpendicular to the conveyance direction.

8 . The film forming method according to claim 1 , wherein the film is an insulating film.

9 . The film forming method according to claim 8 , wherein the insulating film physically insulates the positive electrode from the negative electrode.