Toner for electrophotography, image forming method, and process cartridge

1. A clear toner for electrophotography, comprising a toner in a form of a particle free from a colorant and containing:

a binder resin comprising a polyester resin;

a release agent comprising a monoester wax; and

a metal salt of formula (1):

wherein L 1 denotes:

wherein t-Bu denotes a t-butyl group,

wherein an acid value of the clear toner is 6 mgKOH/g to 12 mgKOH/g,

wherein the polvester resin has a weight average molecular weight (Mw) from 7,000 to 10,000,

wherein a ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the polyester resin is 4 or less,

wherein the polyester resin has an acid value from 4.2 mgKOH/g to 13.2 mgKOH/g, and

wherein a maximum value of loss tangent of the toner at 97° C. to 113° C. is from 9 to 21, as a viscoelasticity of the clear toner is measured, where the loss tangent is represented by the following formula:

Loss tangent (tan δ)=loss elastic modulus ( G ″)/storage elastic modulus ( G ′).

2. The clear toner according to claim 1 , further comprising:

a wax-dispersing agent, which is a copolymer resin comprising at least styrene, butyl acrylate, and acrylonitrile as monomers.

3. The clear toner according to claim 1 , wherein the binder resin comprises 50 mass % or more, based on a total mass of the binder resin, of the polyester.

4. The clear toner according to claim 3 , comprising:

from 4 to 8 parts, relative to 100 parts of the clear toner, of the release agent; and

from 0.5 to 2 parts, relative to 100 parts of the clear toner, of the metal salt.

5. An image forming method, comprising:

superimposing a color toner and the clear toner according to claim 1 to form an image; and

simultaneously fixing the image, in which the color toner and the clear toner are superimposed, on a recording medium.

6. The image forming method according to claim 5 , wherein a difference in glossiness between the color toner and the clear toner is 30 or greater.

7. A process cartridge, comprising:

an image bearer; and

a developing device configured to develop an electrostatic latent image formed on the image bearer with a developer containing a clear toner and a carrier to form a visible image,

wherein the image bearer and the developing device are integratedly supported, and the process cartridge is detachably mounted in a main body of an image forming apparatus, and

wherein the clear toner is the clear toner according to claim 1 .