Toner, development agent, and image forming apparatus
Toner contains a binder resin containing one or more kinds of crystalline resin and one or more kinds of non-crystalline resin. The non-crystalline resin located at the surface portion of the toner forms a shell structure of a continuous phase of the non-crystalline resin and the toner has an amount of melting heat of 30 J/g or more in a second temperature rising as measured by differential scanning calorimetry (DSC).
1. A toner, comprising a binder resin comprising:
one or more kinds of crystalline resin; and
one or more kinds of non-crystalline resin,
wherein:
the one or more kinds of non-crystalline resin is located at a surface portion of the toner and forms a shell structure of a continuous phase;
at least one of the one or more kinds of crystalline resin comprises at least a urethane bond or a urea bond at a main chain thereof; and
the toner has an amount of melting heat of 30 J/g or more in a second temperature rising as measured by differential scanning calorimetry (DSC).
2. The toner according to claim 1 , wherein the one or more kinds of non-crystalline resin comprises a resin incompatible with the one or more kinds of crystalline resin.
3. The toner according to claim 2 , wherein the one or more kinds of non-crystalline resin incompatible with the one or more kinds of crystalline resin is a styrene-(meth)acrylic resin.
4. The toner according to claim 1 , wherein the one or more kinds of non-crystalline resin accounts for from 5% by weight to 30% by weight based on the binder resin and has a glass transition temperature Tg of from 55° C.
5. The toner according to claim 1 , wherein the binder resin comprises two crystalline resins, each comprising at least a urethane bond or a urea bond at a main chain thereof.
6. The toner according to claim 1 , wherein the one or more kinds of crystalline resin comprises a first crystalline resin and a second crystalline resin having a weight average molecular weight Mw greater than the first crystalline resin.
7. The toner according to claim 1 , further comprising a charge control agent comprising a polycondensation element formed by polycondensation reaction of a phenolic compound and an aldehyde.
8. The toner according to claim 1 , wherein, in CHN analysis of a portion in the toner which is soluble in tetrahydrofuran (THF), an amount of nitrogen accounts for from 0.3% by weight to 2.0% by weight.
9. The toner according to claim 1 , wherein the one or more kinds of crystalline resin accounts for 50% by weight or more based in the binder resin.
10. The toner according to claim 1 , manufactured by discharging a toner composition liquid comprising a toner composition containing at least the binder resin through a piercing hole to obtain droplets.
11. A development agent, comprising:
a carrier; and
the toner of claim 1 .
12. An image forming apparatus, comprising:
a latent electrostatic image bearing member;
a latent electrostatic image forming device to form a latent electrostatic image on the latent electrostatic image bearing member;
a development device to develop the latent electrostatic image with the toner of claim 1 to form a visible image;
a transfer device to transfer the visible image to a recording medium; and
a fixing device to fix the visible image on the recording medium.
13. The toner according to claim 1 , wherein the amount of melting heat of the toner ranges from 35 J/g to 69 J/g.
14. The toner according to claim 1 , wherein at least one of the one or more kinds of crystalline resin is a crystalline polyurethane resin.
15. The toner according to claim 1 , wherein at least one of the one or more kinds of crystalline resin is a urethane-modified crystalline polyester resin.
16. The toner according to claim 1 , wherein at least one of the one or more kinds of crystalline resin is a crystalline polyurea resin.