Abstract: A developing apparatus includes a developer container that stores developer, a conveyance screw including a shaft portion and a blade, a bearing portion configured to engage with an engagement portion of the shaft portion of the conveyance screw, and a magnetic seal member having a magnetic property and disposed along a peripheral surface of the shaft portion in a noncontact manner with respect to the shaft portion between the blade and the engagement portion in the rotational axis direction of the conveyance screw.

Abstract: A method of producing a fiber is provided, the method including extruding, from a spinneret, a spinning dope solution containing a fiber-forming polymer dissolved in a solvent, once allowing the solution to run in air, and then guiding the solution into the liquid of a coagulation bath to allow coagulation, wherein a gas-phase portion formed in a vertically downward direction from an extrusion surface of the spinneret to the liquid surface of the coagulation bath has a unidirectional air flow, and has an air flow rate per unit time (Af) which satisfies, in relation to the amount of the solvent in the spinning dope solution per unit time (As) in the gas-phase-portion volume (Vh), the relational expression 0.0008 m3?Af/(As/Vh)?0.0015 m3.

Abstract: A method of producing a fiber, the method including discharge, from a spinneret 1, a spinning dope solution containing a fiber-forming polymer dissolved in a solvent, once allowing the solution to run in air, and then guiding, the solution into the liquid of a coagulation bath 4 to allow coagulation, wherein a gas-phase portion thrilled in a vertically downward direction from a discharge surface of the spinneret 1 to the liquid surface of the coagulation bath 4 has an air flow rate per unit time (Af) which satisfies, in relation to the amount of the solvent in the spinning dope solution per unit time (As) in the gas-phase-portion volume (Vh), the relational expression 0.0008 m3?Af(As/Vh)?0.0015 m3, and the hourly average of the absolute humidity at each of four points in an outer periphery of the spinneret in the gas-phase portion is not more than 20 g/m3.

Abstract: A method of producing a fiber is provided, the method including extruding, from a spinneret, a spinning dope solution containing a fiber-forming polymer dissolved in a solvent, once allowing the solution to run in air, and then guiding the solution into the liquid of a coagulation bath to allow coagulation, wherein a gas-phase portion formed in a vertically downward direction from an extrusion surface of the spinneret to the liquid surface of the coagulation bath has a unidirectional air flow, and has an air flow rate per unit time (Af) which satisfies, in relation to the amount of the solvent in the spinning dope solution per unit time (As) in the gas-phase-portion volume (Vh), the relational expression 0.0008 m3?Af/(As/Vh)?0.0015 m3.

Abstract: A developing apparatus includes a developer container that stores developer, a conveyance screw including a shaft portion and a blade, a bearing portion configured to engage with an engagement portion of the shaft portion of the conveyance screw, and a magnetic seal member having a magnetic property and disposed along a peripheral surface of the shaft portion in a noncontact manner with respect to the shaft portion between the blade and the engagement portion in the rotational axis direction of the conveyance screw.