Toner, method of manufacturing toner, toner storage unit, image forming apparatus and method of forming image

1. A toner comprising:

a crystalline polyester resin; and

an amorphous polyester resin, wherein

a ratio of a storage modulus of the toner G′(To) at a temperature To to the storage modulus of the toner G′(To+3) at a temperature To+3 is greater than or equal to 10, in a case where the temperature To is within a range from 50° C. to 65° C.,

wherein To is a temperature at which the toner starts to melt, and

wherein the storage modulus of the toner G′(100) at a temperature of 100° C. is less than 1000 Pa.

2. The toner according to claim 1 , wherein

a content of the crystalline polyester resin is less than or equal to 15 mass %.

3. The toner according to claim 1 , wherein

a shape factor SF1 of the crystalline polyester resin in a cross-sectional view of the toner is greater than or equal to 100 and less than 130.

4. The toner according to claim 1 , wherein

an endothermic amount derived from the crystalline polyester resin in a first temperature increase of the toner is greater than or equal to 10 J/g,

wherein the endothermic amount is an amount measured with differential scanning calorimetry comprising heating the toner under nitrogen from −80° C. to 150° C. at a rate of 10° C./min.

5. The toner according to claim 1 further comprising:

a vinyl polymer modified polyester resin that is obtained by modifying a crystalline polyester resin using either styrene or (meth) acrylic compound or using both the styrene and the (meth) acrylic compound.

6. A method of manufacturing the toner according to claim 1 comprising:

mixing an aqueous dispersion including a crystalline polyester resin into an oil phase including an amorphous polyester resin, to prepare a water-in-oil type (W/O type) emulsion in which the crystalline polyester resin is included in a state of being dispersed in the oil phase; and

preparing an oil-in-water type (O/W type) emulsion in which the crystalline polyester resin is included in a state of being dispersed in an aqueous medium, by mixing the water-in-oil type (W/O type) emulsion into the aqueous medium.

7. A toner storage unit for storing the toner according to claim 1 .

8. An image forming apparatus comprising:

an electrostatic latent image bearer;

an electrostatic latent image formation unit that forms an electrostatic latent image on the electrostatic latent image bearer;

a developing unit that develops the electrostatic latent image using the toner according to claim 1 , to form a visible image;

a transfer unit that transfers the visible image to a recording medium, to form a transfer image on a surface of the recording medium; and

a fixing unit that fixes the transfer image on the surface of the recording medium.

9. A method of forming an image comprising:

forming an electrostatic latent image on an electrostatic latent image bearer;

developing the electrostatic latent image using the toner according to claim 1 to form a visible image;

transferring the visible image to a recording medium to form a transfer image on a surface of the recording medium; and

fixing the transfer image on the surface of the recording medium.

10. The toner according to claim 2 , wherein

a shape factor SF1 of the crystalline polyester resin in a cross-sectional view of the toner is greater than or equal to 100 and less than 130.

11. The toner according to claim 2 , wherein

an endothermic amount derived from the crystalline polyester resin in a first temperature increase of the toner is greater than or equal to 10 J/g,

wherein the endothermic amount is an amount measured with differential scanning calorimetry comprising heating the toner under nitrogen from −80° C. to 150° C. at a rate of 10° C./min.

12. The toner according to claim 4 , wherein the endothermic amount derived from the crystalline polyester resin in the first temperature increase of the toner is greater than or equal to 10 J/g and less than or equal to 24 J/g.