ELECTROPHOTOGRAPHIC TONER

Abstract

An electrophotographic toner is disclosed, comprising a binding resin, a colorant and a releasing agent, wherein the releasing agent comprises a first releasing agent component and a second releasing agent component, the first releasing agent component is a straight chain hydrocarbon compound exhibiting a melting point of 50 to 100° C. and the second releasing agent component is a branched hydrocarbon compound exhibiting a melting point of 50 to 100° C., and the second releasing agent component accounting for 5% to 90% by mass of the total amount of the first and second releasing agent components.

Description

BRIEF EXPLANATION OF THE DRAWINGS

FIG. 1 illustrates an example of an image forming apparatus for use in an image forming method using the toner of the invention.

FIG. 2 shows a sectional view of an example of a fixing device of an image forming apparatus using the toner of the invention.

FIG. 3 illustrates another example of a fixing device.

FIG. 4 illustrates an example of constitution of a heating roller used in the fixing device shown in FIG. 3.

Claims

1. An electrophotographic toner comprising a binding resin, a colorant and a releasing agent, wherein the releasing agent comprises a first releasing agent component and a second releasing agent component, the first releasing agent component is a straight chain hydrocarbon compound exhibiting a melting point of 50 to 100° C. and the second releasing agent component is a branched hydrocarbon compound exhibiting a melting point of 50 to 100° C., and the second releasing agent component accounting for 5% to 90% by mass of the total amount of the first and second releasing agent components.

2. The toner of claim 1, wherein the first component exhibits a melting point of 55 to 90° C. and the second component exhibits a melting point of 55 to 90° C.

3. The toner of claim 1, wherein the second releasing agent component accounts for 10% to 60% by mass of the total amount of the first and second releasing agent components.

4. The toner of claim 1, wherein the first releasing agent component is at least one selected from the group of a paraffin wax, Fischer-Tropsch wax and a polyethylene wax.

5. The toner of claim 1, wherein the straight chain hydrocarbon compound exhibits a weight average molecular weight (Mw) of 300 to 500 and a number average molecular weight (Mn) of 300 to 500, and the ratio (Mw/Mn) of the weight average molecular weight to the number average molecular weight being from 1.0 to 1.20.

6. The toner of claim 1, wherein the second releasing agent component is at least one selected from the group of microcrystalline wax and an isoparaffin wax.

7. The toner of claim 1, wherein the second releasing agent component is a microcrystalline wax exhibiting a weight average molecular weight of 600 to 800 and a melting point of 60 to 85° C.

8. The toner of claim 1, wherein in the branched hydrocarbon compound, the sum of tertiary and quaternary carbon atoms accounts for 0.1% to 20% of total carbon atoms of the hydrocarbon compound.

9. The toner of claim 1, wherein the releasing agent is contained in an amount of 1% to 30% by mass of the binding resin.