Abstract: A toner container densely packed with toner to be replenished into a developing unit included in an image forming apparatus, and a method of producing the same. The toner is packed in the container with a ratio of a packing density to a saturation bulk density greater than 1.0, a mean penetration greater than 5.0 mm inclusive, and a standard deviation of penetration not exceeding one-fifth of the mean penetration. The toner can be smoothly and continuously replenished into the developing unit so as to form a number of images matching the amount thereof.

Abstract: A powder feeding method includes the steps of injecting a gaseous medium into a powder material held in a hopper from a porous wall forming a funnel at a bottom part of said hopper, such that the injection of the gaseous medium is carried out intermittently.

Abstract: A powder filling method and a powder filling device for filling a powder such as toner, chemical, cosmetics or food material in a powder container efficiently at a high density includes the steps of inserting an air aspirating pipe in a powder filled in a powder container, aspirating air in the powder through the air aspirating pipe, and moving one end of the air aspirating pipe from a bottom portion to a top portion of the powder container, corresponding to an amount of the powder filled.