Konica Minolta, Inc.

Yuya Kubo

Daisuke Watanabe

Shiro Hirano

Takanari Kayamori

Kenichi Onaka

Saburou Hiraoka

Kishio Tamura

Kazuhiko Nakajima

The toner for developing an electrostatic charge image of the present invention contains a toner base particle comprising a binder resin and at least two kinds of organic pigments, and strontium titanate as an external additive.

Toner for developing an electrostatic charge image and an image forming method

The toner for developing an electrostatic charge image of the present invention contains a toner base particle comprising a binder resin and at least two kinds of organic pigments, and alumina as an external additive. The at least two kinds of organic pigments comprises: a pigment P1 having an absorption maximum wavelength &#x3bb;max (nm) of greater than 400 nm and less than 600 nm when dispersed in methyl ethyl ketone; and a pigment P2 having an absorption maximum wavelength &#x3bb; max (nm) of 600 nm or more and 700 nm or less when dispersed in methyl ethyl ketone.

An image forming method includes forming an image by transferring and fixing white toner and color toner of at least one color to a recording medium, wherein when an endothermic peak top temperature and a toner softening point in a first temperature increasing process in differential scanning calorimetry of the white toner are Tmw (&#xb0; C.) and Tspw (&#xb0; C.), respectively, and an endothermic peak top temperature and a toner softening point in a first temperature increasing process in differential scanning calorimetry of the color toner are Tmc (&#xb0; C.) and Tspc (&#xb0; C.), respectively, Equations (1) and (2) below are satisfied:[Math. 1]3&#x2264;()&#x2264;20&#x2003;&#x2003;(1)&#x2003;&#x2003;(2)

Image forming method using white toner and color toner of at least one color

The present invention provides a means for suppressing an occurrence of a ghost by enhancing diffraction efficiency of a holographic optical element having a volume hologram recording layer. The present invention is a holographic optical element including: a volume hologram recording layer containing a photopolymer; and at least one adjacent layer which is in contact with the volume hologram recording layer and contains a resin, wherein a diffraction grating is formed so as to extend from the volume hologram recording layer to the adjacent layer.

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Hino, Japan

Yuya Kubo