Controller for injection molding machine, injection molding machine, and control method for injection molding machine

A controller for an injection molding machine including an injecting member configured to push a molding material in a forward direction, the molding material containing a bioplastic;

• and an injection drive source configured to cause the injecting member to travel forward or backward, the controller comprising:
• processing circuitry configured to perform filling in which a forward travel speed of the injecting member is controlled so that an actual value of a pressure applied from the injecting member to the molding material containing the bioplastic does not exceed an upper limit of the pressure, wherein
• in at least a part of the filling, a value of from 550 mm/s through 700 mm/s is settable as a set value of the forward travel speed of the injecting member, and a value of 200 MPa or higher is settable as the upper limit of the pressure.