Toner, process cartridge and image-forming apparatus

A process cartridge attachable to and detachable from an image-forming apparatus, the process cartridge comprising:

• a toner, and
• a toner container accommodating the toner, wherein
• the toner comprises a toner particle containing a binder resin, a block copolymer A, and an ester wax B,
• the binder resin contains a styrene-acrylic copolymer,
• a content of the styrene-acrylic copolymer in the binder resin is 50 mass % or more,
• the block copolymer A is a block copolymer including a polyolefine segment and a polystyrene segment, and the polyolefine segment includes an olefine unit C represented by any of formulae (1) to (4):
• the ester wax B is miscible with 100 parts by mass of a styrene-n-butyl acrylate copolymer α having the following composition in an amount of 15.0 parts by mass or more at 100° C.:
• the styrene-n-butyl acrylate copolymer α is a copolymer of 75 parts by mass of a styrene monomer and 25 parts by mass of an n-butyl acrylate monomer,
• the styrene-n-butyl acrylate copolymer α has a weight-average molecular weight of 29,000 or more and 31,000 or less, and
• the ester wax B is an ester compound having a structure of formula (5) or a structure of formula (6):
• in formula (5), R1 and R3 each independently represent an n-alkyl group having 13 to 21 carbon atoms, and R2 represents an alkylene group having 2 to 8 carbon atoms);
• in formula (6), R4 and R6 each independently represent an n-alkyl group having 14 to 22 carbon atoms, and R5 represents a single bond or an alkylene group having 1 to 6 carbon atoms.

An image-forming apparatus comprising:

• a toner;
• a toner carrier carrying the toner;
• an electrostatic latent image carrier;
• a charging device that charges the surface of the electrostatic latent image carrier by a charging member;
• an electrostatic latent image-forming device forming an electrostatic latent image on the charged electrostatic latent image carrier;
• a developing device for developing the electrostatic latent image using the toner to form a toner image on the electrostatic latent image carrier;
• a transfer device for transferring the toner image to a recording medium;
• and
• a fixing device for fixing the toner image transferred on the recording medium to the recording medium, wherein
• the toner comprises a toner particle containing a binder resin, a block copolymer A, and an ester wax B,
• the binder resin contains a styrene-acrylic copolymer,
• a content of the styrene-acrylic copolymer in the binder resin is 50 mass % or more,
• the block copolymer A is a block copolymer including a polyolefine segment and a polystyrene segment, and the polyolefine segment includes an olefine unit C represented by any of formulae (1) to (4):
• the ester wax B is miscible with 100 parts by mass of a styrene-n-butyl acrylate copolymer α having the following composition in an amount of 15.0 parts by mass or more at 100° C.:
• the styrene-n-butyl acrylate copolymer α is a copolymer of 75 parts by mass of a styrene monomer and 25 parts by mass of an n-butyl acrylate monomer,
• the styrene-n-butyl acrylate copolymer α has a weight-average molecular weight of 29,000 or more and 31,000 or less, and
• the ester wax B is an ester compound having a structure of formula (5) or a structure of formula (6):
• in formula (5), R1 and R3 each independently represent an n-alkyl group having 13 to 21 carbon atoms, and R2 represents an alkylene group having 2 to 8 carbon atoms;
• in formula (6), R4 and R6 each independently represent an n-alkyl group having 14 to 22 carbon atoms, and R5 represents a single bond or an alkylene group having 1 to 6 carbon atoms.