Electrophotographic toner binder, and toner composition

An electrophotographic toner composition comprising:

• an electrophotographic toner binder, and colorant,
• wherein,
• a content of the electrophotographic toner binder in the electrophotographic toner composition is 30 to 97% by weight, and the electrophotographic toner binder comprises:
• a polymer (A) containing a monomer (a) and a monomer (x) different from the monomer (a) as essential constituent monomers,
• wherein the monomer (a) is behenyl (meth)acrylate, the polymer (A) has an acid value of 40 or less, and the polymer (A) satisfies the following relational expression (1):
• 1.1 (cal/cm3)0.5≤|SP(x)−SP(a)|≤8.0 (cal/cm3)0.5 relational expression (1):
• wherein SP(a) is the solubility parameter (SP value) of a structural unit derived from the monomer (a) constituting the polymer (A);
• and SP(x) is the SP value of a structural unit derived from the monomer (x) different from the monomer (a) constituting the polymer (A),
• wherein an amount of the monomer (a) as a constituent monomer constituting the polymer (A) is 30 to 99% by weight, based on the weight of the polymer (A),
• wherein the monomer (x) includes at least one monomer (c) selected from the group consisting of vinylbenzene, methyl methacrylate, and methyl acrylate, and a monomer (b) having an ethylenically unsaturated bond, and at least one functional group selected from the group consisting of a nitrile group, a urethane group, a urea group, an imide group, an allophanate group, an isocyanurate group, and a biuret group, wherein the monomer (b) includes a monomer (b1) having a nitrile group and a monomer (b3) having a urea group.