A color toner printer system that is configured to both over print in a single pass and under print in a single pass, and that is configured to switch between over and under printing, the system comprising: a color toner printer comprising at least four toner printing cartridge slots, a front slot, a second slot, a third slot, and a rear slot, which are configured to matingly engage with at least four toner printing cartridges comprising three color toner printing cartridges and a non-standard toner printing cartridge; and a raster image processor software. The color toner printer is configured to over print when the non-standard toner printing cartridge is in said rear slot, and to under print when the non-standard toner printing cartridge is in said front slot. The RIP software is configured to (1) remap the color toner printer to reflect an actual placement of the at least four toner printing cartridges and (2) allows said color toner printer to under print in a single pass or over print in a single pass.

In one example, a printing process includes: forming a first latent image on a photoconductor; applying a first LEP ink to the photoconductor to develop the first latent image into a first ink image; forming a second latent image having a first part on the first ink image and a second part on the photoconductor; and applying a second LEP ink to the first ink image and to the photoconductor to develop the second latent image into a second ink image and form a composite on the photoconductor in which some of the second ink image overlaps some of the first ink image.

Provided here are toner sets and image forming apparatus and methods for the formation of a bright image with excellent brightness and concealability. A toner set according to an embodiment comprises a first toner which is stored in a first container and comprises a plurality of first toner particles containing a first bright pigment and a first binder resin, and a second toner which is stored in a second container and comprises a plurality of second toner particles containing a second bright pigment and a second binder resin, wherein the second toner has a larger volume average particle diameter than the first toner.

An image forming apparatus has a normal image formation mode and a wide color gamut image formation mode in which an amount of a developer per unit area of a developer image of at least a color that differs from a prescribed color among a plurality of colors is increased as compared to the normal image formation mode. Image data is generated such that an image portion formed in the prescribed color in an image formed on a recording material is formed solely by a developer image of the prescribed color in the normal image formation mode, but formed by superimposing a developer image of a color that differs from the prescribed color on a developer image of the prescribed color or formed solely by a developer image of a different color in place of a developer image of the prescribed color in the wide color gamut image formation mode.

Provided is an image formation device including a photoreceptor configured to carry a toner image and a developer configured to form the toner image on a surface of the photoreceptor and configured such that the developer is a replaceable development unit, the image formation device including: a development bias application section configured to apply a development bias to between the photoreceptor and the developer; a stabilization control section configured to perform image stabilization control of determining a development bias value to be used in future by changing the development bias while measuring a density of the toner image formed by the developer, thereby obtaining the toner image with a target density; and a life determination section configured to determine expiration of use of the development unit when the development bias value determined by the stabilization control falls outside a preset acceptable range.

An image forming apparatus includes a photosensitive member, a charging roller, an exposure device, a developing device, a transfer member, a fixing device, an outputting portion for outputting a recording material on which a toner image is fixed, a voltage source for output the charging voltage, a voltage setting portion for setting the charging voltage, an executing portion for executing an output process of a test chart including a plurality of adjusting images in setting of peak-to-peak voltage values of AC voltages at a plurality of different values, and an inputting portion through which an instruction of execution of the output process of the test chart is inputted.

A color toner printer system that is configured to both over print in a single pass and under print in a single pass, and that is configured to switch between over and under printing, the system comprising: a color toner printer comprising at least four toner printing cartridge slots, a front slot, a second slot, a third slot, and a rear slot, which are configured to matingly engage with at least four toner printing cartridges comprising three color toner printing cartridges and a non-standard toner printing cartridge; and a raster image processor software. The color toner printer is configured to over print when the non-standard toner printing cartridge is in said rear slot, and to under print when the non-standard toner printing cartridge is in said front slot. The RIP software is configured to (1) remap the color toner printer to reflect an actual placement of the at least four toner printing cartridges and (2) allows said color toner printer to under print in a single pass or over print in a single pass.

In one example, a printing process includes: forming a first latent image on a photoconductor; applying a first LEP ink to the photoconductor to develop the first latent image into a first ink image; forming a second latent image having a first part on the first ink image and a second part on the photoconductor; and applying a second LEP ink to the first ink image and to the photoconductor to develop the second latent image into a second ink image and form a composite on the photoconductor in which some of the second ink image overlaps some of the first ink image.

In one example, a printing process includes: forming a first latent image on a photoconductor (24); applying a first LEP ink (30) to the photoconductor to develop the first latent image into a first ink image; forming a second latent image having a first part on the first ink image and a second part on the photoconductor; and applying a second LEP ink (32, 34, 36) to the first ink image and to the photoconductor to develop the second latent image into a second ink image and form a composite on the photoconductor in which some of the second ink image overlaps some of the first ink image.

An image forming apparatus has a normal image formation mode and a wide color gamut image formation mode in which an amount of a developer per unit area of a developer image of at least a color that differs from a prescribed color among a plurality of colors is increased as compared to the normal image formation mode. Image data is generated such that an image portion formed in the prescribed color in an image formed on a recording material is formed solely by a developer image of the prescribed color in the normal image formation mode, but formed by superimposing a developer image of a color that differs from the prescribed color on a developer image of the prescribed color or formed solely by a developer image of a different color in place of a developer image of the prescribed color in the wide color gamut image formation mode.