Abstract: Provided is a flexible printed circuit connection structure which includes a flexible printed circuit having a plurality of wires, a board to be connected having a plurality of wires to be connected, a plurality of solder connection portions, and a partition wall, in which: the plurality of solder connection portions is a part where the plurality of wires of the flexible printed circuit and the plurality of wires to be connected of the board to be connected are connected to each other by solder; the partition wall is provided away from the plurality of solder connection portions so as to surround the plurality of solder connection portions; and the flexible printed circuit, the board to be connected, and the partition wall define a sealed space, and the plurality of solder connection portions is arranged inside the sealed space.

Abstract: A toner for developing electrostatic images which is obtained by melt mixing at least a binder resin and a coloring agent, forming a powder material by pulverizing the obtained mixture after cooling and removing rough particles and fine particles from the formed powder material by classification, wherein inorganic fine particles having a roundness of 1.00 to 1.30, an average of the diameter of primary particles of 0.05 to 0.45 ?m and a ratio of a standard deviation to the average of the diameter of primary particles of 0.25 or smaller are added as an external additive, and a process for producing a toner for developing electrostatic images which comprises melt mixing at least a binder resin and a coloring agent, forming a powder material by pulverizing the obtained mixture after cooling, rounding the powder material by a heat treatment and adding the above inorganic fine particles to the rounded powder material.

Abstract: A toner for developing electrostatic images which is obtained by melt mixing at least a binder resin and a coloring agent, forming a powder material by pulverizing the obtained mixture after cooling and removing rough particles and fine particles from the formed powder material by classification, wherein inorganic fine particles having a roundness of 1.00 to 1.30, an average of the diameter of primary particles of 0.05 to 0.45 ?m and a ratio of a standard deviation to the average of the diameter of primary particles of 0.25 or smaller are added as an external additive, and a process for producing a toner for developing electrostatic images which comprises melt mixing at least a binder resin and a coloring agent, forming a powder material by pulverizing the obtained mixture after cooling, rounding the powder material by a heat treatment and adding the above inorganic fine particles to the rounded powder material.