Coating film production apparatus and coating film production method using the same
A high-quality coating film with a uniform thickness is produced without crush of coating particles even in a case where a wet coating material that does not require a step of drying the coating material is used, while maintaining high productivity. By providing a surface layer with an optimized hardness on the surface of a roll used for supply of a mixture coating material, a high-quality coating film with a uniform thickness can be produced, even in a case where a wet coating material that does not require a step of drying the coating material is used, while maintaining high productivity.
1. A coating film production apparatus that produces a coating film, said apparatus comprising:
a feeder supplying a mixture coating material including coating particles; and
one or two first rolls and a second roll facing the first rolls configured to provide a gap between the first rolls and the second roll and roll the mixture coating material,
wherein the feeder supplies the mixture coating material to the gap between the first rolls and the second roll, at least one of the first rolls has, on its surface, a surface layer configured to press the mixture coating material so that a penetration depth of the coating particles into the surface layer in rolling the mixture coating material is 5% to 50% of a diameter of the coating particles,
the coating particles include one of: (1) artificial graphite particles having a collapse pressure of a granule that is an aggregate of the coating particles of approximately 0.02 GPa and a crush pressure of approximately 0.3 GPa; and (2) nickel-based cathode material particles having a collapse pressure of approximately 0.02 GPa and a crush pressure of approximately 50 GPa;
a surface layer of the at least one of the first rolls includes at least one of: (1) a fluororesin film; and a (2) diamond-like carbon (DLC) film; and
a relational expression of a Young's modulus of the surface layer is: a crush pressure of the coating particles×20>the Young's modulus of the surface layer>a collapse pressure of the granule.