Konica Minolta, Inc.

Yusuke Takigaura

Takaki Kawamura

Shiro Hirano

Natsuki Ito

Ami Motohashi

Hiroshi Nagasawa

Noboru Ueda

A toner set includes a plurality of toners, wherein the toner set includes a first toner containing a yellow colorant and a second toner containing a cyan colorant, the first toner and the second toner each contain a binder resin containing a vinyl-based resin and a crystalline resin, and a release agent containing a hydrocarbon wax, a content of the vinyl-based resin with respect to a total mass of the binder resin is 50% by mass or more, the first toner contains the crystalline resin having a moiety having a crystal structure and a crystal nucleating agent moiety having a crystal nucleating agent, and the second toner contains the cyan colorant that is a compound represented by general formula (1).

Toner set and image forming method

An object of the present invention is to provide an image forming method capable of coating a photocurable varnish without unevenness on a toner image formed using an electrostatic latent image developing toner, and further having good adhesion between a varnish layer and the toner image. The image forming method of the present invention comprises: forming a toner image on a recording medium using an electrostatic latent image developing toner containing a toner particle comprising a binder resin and a release agent; and forming a varnish layer on the toner image by applying and curing a photocurable varnish comprising a photocurable compound. The binder resin comprised in the electrostatic latent image developing toner contains a crystalline polyester resin. The photocurable compound comprised in the photocurable varnish comprises a diol di(meth)acrylate having a straight hydrocarbon chain.

Image forming method

An electrostatic charge image developing toner includes a binder resin and a release agent. A ratio of a crystalline polyester resin to the total amount of a amorphous polyester resin and the crystalline polyester resin is within a range exceeding 40% by mass to 60% by mass. A temperature at which a storage modulus before heat left G' before being left to stand at a temperature of X&#xb0; C. becomes 1.0&#xd7;10Pa is within a range exceeding 45&#xb0; C. to 55&#xb0; C. A storage modulus after heat left G&#x2032; at a temperature of X&#x2032;&#xb0; C. at which a value of a ratio of the storage modulus after heat left G&#x2032; at a temperature of X&#xb0; C. after being left to stand at the temperature of X&#xb0; C. for 2 hours to the storage modulus before heat left G&#x2032; at the temperature of X&#xb0; C. becomes the maximum is within a range of 1.0&#xd7;10to 5.0&#xd7;10Pa.

Electrostatic charge image developing toner

An electrostatic charge image developing toner includes a particulate toner matrix containing a binder resin and an external additive. The binder resin includes an amorphous polyester resin, a crystalline resin, and an amorphous vinyl resin. A storage modulus G'(t) measured before the toner is left and storage moduli G&#x2032;(t) and G&#x2032;(t) measured after the toner is left for three hours at temperatures (T-10)&#xb0; C. and (T-20)&#xb0; C., respectively, based on a melting point (T&#xb0; C.) derived from the crystalline resin satisfy the relations represented by G&#x2032;(t)&#x3c;G&#x2032;(t), G&#x2032;(t)&#x3c;G&#x2032;(t), and G&#x2032;(x)/G&#x2032;(x)&#x2264;1.5 in a temperature range A for measurement where the storage modulus G&#x2032;(t) is 1.0&#xd7;10Pa or more. The value t represents any temperature (&#xb0; C.) for measurement in the temperature range A for measurement; and the value x represents the temperature (&#xb0; C.) for measurement having a maximum difference between the storage moduli G&#x2032;(t) and G&#x2032;(t).

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Hino, Japan

Yusuke Takigaura