Toner, developer, toner cartridge, and image forming apparatus
View Patent ↗A toner contains a binder resin and a polyalkylene, wherein the following formula is satisfied: 2≦ A/B ≦100 where A represents a reflectance at a light-receiving angle of +30° and B represents a reflectance at a light-receiving angle of −30°, A and B being measured when a solid fixed image formed by the toner is irradiated with incident light at an incident angle of −45° using a goniophotometer.
1. A toner comprising:
a binder resin;
pigment particles; and
a polyalkylene,
wherein
the following formula is satisfied:
2 ≦A/B≦ 100
where A represents a reflectance at a light-receiving angle of +30° and B represents a reflectance at a light-receiving angle of −30°, A and B being measured when a solid fixed image formed by the toner is irradiated with incident light at an incident angle of −45° using a goniophotometer,
the polyalkylene has a melting temperature of from 75° C. to 110° C.,
the polyalkylene has a full width at half maximum of melting of from 5° C. to 20° C., and
the toner has an average equivalent-circle diameter D, which is larger than an average maximum thickness C of the toner, and the following formula is satisfied:
E≧ 60
where E represents a ratio (%) of a number of pigment particles having long-axis directions that form an angle of −30° to +30° with respect to a long-axis direction of a cross section of the toner in a thickness direction thereof to a total number of pigment particles observed in the cross section.
2. The toner according to claim 1 , wherein the polyalkylene has a melt viscosity of from 1.0 Pa·s to 12.0 Pa·s.
3. The toner according to claim 1 , wherein the polyalkylene has a melt viscosity of from 2.0 Pa·s to 10.0 Pa·s.
4. The toner according to claim 1 , wherein a ratio (C/D) of the average maximum thickness C of the toner to the average equivalent-circle diameter D of the toner is in a range of from 0.001 to 0.500.
5. The toner according to claim 1 , further comprising pigment particles flaky in shape.
6. A developer comprising:
the toner according to claim 1 ; and
a carrier.
7. The developer according to claim 6 , wherein the toner has a ratio (C/D) of the average maximum thickness C of the toner to the average equivalent-circle diameter D of the toner in a range of from 0.001 to 0.500.
8. A toner cartridge comprising a container that contains the toner according to claim 1 .
9. The toner cartridge according to claim 8 , wherein the toner has a ratio (C/D) of the average maximum thickness C to the average equivalent-circle diameter D in a range of from 0.001 to 0.500.