Toner for developing electrostatic latent image, process for producing the same, process for forming image, apparatus for forming image and toner cartridge

A process for producing a toner for developing an electrostatic latent image, comprising the steps of:

• mixing a resin particle dispersion containing first resin particles dispersed therein, a colorant particle dispersion containing colorant particles dispersed therein and a releasing agent particle dispersion containing releasing agent particles dispersed therein, each of which has a center particle diameter of 1 μm or less, to form a core aggregated particles containing the first resin particles, the colorant particles and the releasing agent particles, the first resin particles having a number average molecular weight Mn in a range of from 10,000 to 30,000 and a ratio (Mz/Mw) of a Z average molecular weight Mz and a weight average molecular weight Mw in a range of from 3.0 to 6.0;
• forming a shell layer containing second resin particles on a surface of the core aggregated particles to obtain a core/shell aggregated particles;
• and
• heating the core/shell aggregated particles to a temperature equal to or higher than a glass transition temperature of the first resin fine particles or the second resin fine particles to coalesce the core/shell aggregated particles.

A process for forming an image comprising the steps of:

• charging a surface of a member for holding an image;
• forming an electrostatic latent image on the charged surface of the member for holding an image corresponding to image information;
• developing the electrostatic latent image formed on the surface of the member for holding an image with a developer containing a toner to obtain a toner image;
• and
• fixing the toner image on a surface of a recording medium,
• the toner having a number average molecular weight Mn in a range of from 10,000 to 30,000 and a ratio (Mz/Mw) of a Z average molecular weight Mz and a weight average molecular weight Mw in a range of from 3.0 to 6.0.

An apparatus for forming an image comprising:

• a charging unit for charging a surface of a member for holding an image;
• an electrostatic latent image forming unit for forming an electrostatic latent image corresponding to image information on the charged surface of the member for holding an image;
• a developing unit for developing the electrostatic latent image formed on the surface of the member for holding an image with a developer containing a toner to obtain a toner image;
• and
• a fixing unit for fixing the toner image on a surface of a recording medium,
• the toner having a number average molecular weight Mn in a range of from 10,000 to 30,000 and a ratio (Mz/Mw) of a Z average molecular weight Mz and a weight average molecular weight Mw in a range of from 3.0 to 6.0.