Magnetic toner
AssigneeCanon Kabushiki Kaisha
InventorsYoshihiro Ogawa, Takashige Kasuya, Syuhei Moribe, Kouji Nishikawa
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Abstract
Provided is a magnetic toner comprising magnetic toner particles each comprising at least a binder resin and a magnetic iron oxide, the magnetic toner being excellent in developability and environmental stability, and being capable of reducing a toner consumption. A saturation magnetization σs and a remanent magnetization σr of the magnetic toner in a measured magnetic field of 795.8 kA/m are arranged in the range of 5 to 60 Am2/kg and in the range of 0.1 to 10.0 Am2/kg, respectively, and the binder resin having a polyester component polymerized by using a Ti chelate compound as a catalyst is used.
Claims6
A magnetic toner comprising magnetic toner particles each comprising at least a monoazo iron compound, an aluminum compound of an aromatic hydroxyl carboxylic acid, a binder resin and a magnetic iron oxide, wherein:
- the magnetic toner has a saturation magnetization σs being in the range of 5 to 60 Am2/kg and a remanent magnetization or being in the range of 0.1 to 10.0 Am2/kg in a measured magnetic field of 795.8 kA/m;
- the binder resin contains a polyester component polymerized by using a Ti chelate compound having a ligand selected from the group consisting of a diol, a dicarboxylic acid, and an oxycarboxylic acid as a catalyst;
- and the Ti chelate compound is represented by any one of the following formulae (I) to (IV):
- in the formula (I), R1 denotes one of an alkylene group or an alkenylene group each having 2 to 10 carbon atoms and may have a substituent, M denotes a countercation, m denotes a cation number, n denotes a cation valence, n=2 when m=1, n=1 when m=2, and M denotes one of a hydrogen ion, an alkali metal ion, an ammonium ion, or an organic ammonium ion when n=1, or denotes an alkali earth metal ion when n=2;
- in the formula (II), R2 denotes one of an alkylene group or an alkenylene group each having 1 to 10 carbon atoms and may have a substituent, M denotes a countercation, m denotes a cation number, n denotes a cation valence, n=2 when m=1, n=1 when m=2, and M denotes one of a hydrogen ion, an alkali metal ion, an ammonium ion, or an organic ammonium ion when n=1, or denotes an alkali earth metal ion when n=2;
- in the formula (III), M denotes a countercation, m denotes a cation number, n denotes a cation valence, n=2 when m=1, n=1 when m=2, and M denotes one of a hydrogen ion, an alkali metal ion, an ammonium ion, or an organic ammonium ion when n=1, or denotes an alkali earth metal ion when n=2;
- in the formula (IV), R3 denotes one of an alkylene group or an alkenylene group each having 1 to 10 carbon atoms and may have a substituent, M denotes a countercation, m denotes a cation number, n denotes a cation valence, n=2 when m=1, n=1 when m=2, and M denotes one of a hydrogen ion, an alkali metal ion, an ammonium ion, or an organic ammonium ion when n=1, or denotes an alkali earth metal ion when n=2, wherein the polyester component comprises a compound having a structure containing oxyalkylene ether of a novolak phenolic resin as an alcohol component;
- and wherein the metal compound of an aromatic hydroxyl carboxylic acid is represented by the following formula (13):
- wherein M represents aluminum;
- (B) represents (I) a group of the following structure:
- which may contain a substituent, wherein X represents a hydrogen atom, a halogen atom, or a nitro group;
- or (ii)
- wherein, R represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an alkenyl group having 2 to 18 carbon atoms, A′+ represents hydrogen, a sodium ion, a potassium ion, an ammonium ion, or an aliphatic ammonium ion and Z represents —O— or —C(═O)—O—.
Dependencies are inferred from the claim text.