Two-component developer, container filled with the two-component developer, and image formation apparatus

An image formation apparatus with the built-in container filled with a two-component developer consisting of a toner, which contains at least a resin and a colorant and to which an external additive is added, and a carrier,

• wherein a number average molecular weight of said toner is 3,000 or less;
• wherein
• molecules having a molecular weight of 1,000 or less are contained at 40 number % or more;
• and
• wherein said carrier satisfies general formula (1) as follows:
• 3,000,000≦σ1000×Dc3≦20,000,000 (1)
• wherein σ1000 represents a magnetization in emu/g of a carrier at 1,000 oersted;
• and
• wherein Dc represents a volume average particle diameter in μm of said carrier.

A two-component developer consisting of a toner, which contains at least a resin and a colorant and to which an external additive is added, and a carrier;

• wherein a number average molecular weight of said toner is 3,000 or less;
• wherein molecules having a molecular weight of 1,000 or less are contained at 40 number % or more;
• and
• wherein said carrier satisfies formula (1) as follows:
• 3,000,000≦σ1000×Dc3≦20,000,000 (1)
• wherein σ1000 represents a magnetization in emu/g of the carrier at 1,000 oersted;
• and
• wherein Dc represents a volume average particle diameter in μm of said carrier;
• wherein said carrier has a volume average particle diameter of 15 to 45 μm, and contains carrier particles smaller than 22 μm at 1 to 20%, carrier particles smaller than 16 μm at 3% or less, carrier particles of 62 μm or more at 2 to 15%, and carrier particles of 88 μm or more at 2% or less.

A two-component developer consisting of a toner, which contains at least a resin and a colorant and to which an external additive is added, and a carrier;

• wherein a number average molecular weight of said toner is 3,000 or less;
• wherein molecules having a molecular weight of 1,000 or less are contained at 40 number % or more;
• and
• wherein said carrier satisfies formula (1) as follows:
• 3,000,000≦σ1000×Dc3≦20,000,000 (1)
• wherein σ1000 represents a magnetization in emu/g of the carrier at 1,000 oersted;
• and
• wherein Dc represents a volume average particle diameter in μm of said carrier;
• wherein a saturation magnetization of said carrier to an applied magnetic field of 1,000 oersted is 40 to 120 emu/g, a residual magnetization is not more than 10 emu/g, and a coercive force is not more than 60 oersted.