Provided is a toner for developing electrostatic images, which is less likely to cause filming, is excellent in printing durability, and is less likely to cause fog under a high temperature and high humidity environment. The toner for developing electrostatic images is a toner containing colored resin particles that contains a binder resin, a colorant and a charge control agent, and external additives, wherein the external additives include at least: silica fine particles A, silica fine particles B, and electroconductive metal oxide fine particles C; wherein the silica fine particles. A and B are silica fine particles surface-hydrophobized with at least one hydrophobizing agent; wherein the electroconductive metal oxide fine particles C have an electrical resistance of 70 cm or less and contain antimony-doped tin oxide.

An electrostatic latent image developing toner includes a plurality of toner particles each including a toner mother particle and an external additive attached to a surface of the toner mother particle. The external additive includes a plurality of resin particles each containing first temperature responsive polymer domains and second temperature responsive polymer domains. The second temperature responsive polymer domains have a lower critical solution temperature (LCST) higher than that of the first temperature responsive polymer domains.

An electrostatic latent image developing toner includes a plurality of toner particles each including a toner mother particle and an external additive attached to a surface of the toner mother particle. The external additive includes a plurality of resin particles each containing first temperature responsive polymer domains and second temperature responsive polymer domains. The second temperature responsive polymer domains have a lower critical solution temperature (LCST) higher than that of the first temperature responsive polymer domains.

The magenta toner for developing electrostatic images includes colored resin particles containing a binder resin and a magenta colorant, and an external additive. A volume average particle diameter of the colored resin particles is from 5.5 m to 7.0 m. The external additive contains silica particles. The silica particles contain at least silica particles A having a number average particle diameter of from 5 nm to 30 nm and silica particles B having a number average particle diameter of from 31 nm to 100 nm; wherein a total content of the silica particles is from 0.5 part by mass to 4.5 parts by mass, with respect to 100 parts by mass of the colored resin particles. A liberation rate of the silica particles calculated by a specific liberation rate measuring method is in a range of from 2.2% to 9.5%.

A positively chargeable toner includes a plurality of toner particles each including a toner mother particle and external additives adhering to a surface of the toner mother particle. The toner particles of the positively chargeable toner each include a silica particle as one of the external additives and a titania particle as another one of the external additives. The silica particle has on a surface thereof an alkyl group having a carbon number of at least 8 and no greater than 16 and an amino group. The titania particle has an amino group on a surface thereof. The titania particle has a volume resistivity of at least 1.010.sup.9 .Math.cm and no greater than 1.010.sup.11 .Math.cm. The silica particles have an average primary particle diameter larger than that of the titania particles.

There is provided an electrophotographic photosensitive member, a process cartridge and an electrophotographic apparatus in which residual potential is suppressed and a ghost image is prevented from being generated in a low-humidity environment in an undercoat layer of the electrophotographic photosensitive member. An electrophotographic photosensitive member including: an undercoat layer containing a strontium titanate particle having a maximum peak at a position of 2=32.200.20 ( represents a Bragg angle) in a CuK characteristic X-ray diffraction pattern and a half-value width of the maximum peak of 0.10 deg or more and 0.50 deg or less, and a titanium oxide particle; and a photosensitive layer containing a polyvinyl butyral resin, and a process cartridge and an electrophotographic apparatus each provided with the electrophotographic photosensitive member.

An electrostatically charged image developing toner includes a particulate toner matrix containing an external additive on the surface of the particulate toner matrix. The external additive includes silica particles A and silica particles B. The silica particles A have a number average primary-particle diameter in the range of 40 to 100 nm and an average circularity in the range of 0.50 to 0.90, and are surface-modified with silicone oil. The silica particles B have a number average primary-particle diameter of 25 nm or more and smaller than the number average primary-particle diameter of the silica particles A, and are surface-modified with alkylalkoxysilane having a specific structure or silazane.

A positively chargeable toner includes a plurality of toner particles. Each of the toner particles includes a toner mother particle and an external additive adhering to a surface of the toner mother particle. The external additive includes a plurality of resin particles. Each of the resin particles has a resin mother particle and a coat layer covering at least a portion of a surface of the resin mother particle. The coat layer contains a specific vinyl resin.

An electrostatic charge image developing toner includes toner particles including a particulate toner matrix and an external additive adhering to a surface of the particulate toner matrix. The particulate toner matrix includes a crystalline polyester resin. The external additive includes silica particles. The silica particles are secondary particles including primary particles having a diameter in the range of 30 to 90 nm. The secondary particles have an average circularity in the range of 0.25 to 0.50. The secondary particles have an average aspect ratio of 3.0 or more.

An electrostatic latent image developing toner includes toner particles. Each of the toner particles includes a toner mother particle and an external additive. The toner mother particle contains a binder resin. The external additive includes external additive particles adhering to a surface of the toner mother particle. Each of the external additive particles includes a titanium oxide particle and resin particles adhering to a surface of the titanium oxide particle.