A belt transfer type multi-function device includes a control device performing controlling such that an image to be printed on paper already caught between a transfer roller and the belt roller is printed, and if printing should not be performed on a next paper, movement of the next paper is stopped on a transfer path before the next paper is positioned between the transfer roller and the belt roller, the image already transferred on the transfer belt is deleted in a state in which the next paper is stopped on the transfer path, and the next paper in a stopped state is ejected as a blank paper through a ejection port along the transfer path, so that the image already transferred to the transfer belt, which is to be printed on the next paper along the movement direction of paper, is not printed on the next paper.

An image forming apparatus according to an embodiment includes a decolorable image forming unit that forms a decolorable image with a decolorable material. A mask control unit controls the decolorable image forming unit to form, with the decolorable material on a sheet, a mask that hides at least one portion of an image formed on the sheet with non-decolorable material.

Disclosed is a belt transfer type multi-function device for printing an image transferred on a belt to paper moving between a transfer roller and a belt roller, including a control device performing controlling such that an image to be printed on paper already caught between the transfer roller and the belt roller is printed as it is, and if printing should not be performed on next paper along a movement direction of paper, movement of the next paper is stopped on a transfer path of paper before the next paper is positioned between the transfer roller and the belt roller, the image already transferred on the transfer belt is deleted in a state in which the next paper is maintained to be stopped on the transfer path of paper, and the next paper in a stopped state is ejected as a blank paper through a ejection port of printed paper along the transfer path of paper, so that the image already transferred to the transfer belt, which is to be printed on the next paper along the movement direction of paper, is not printed on the next paper.

An image forming apparatus includes: an inverting unit that inverts a sheet when an image forming process for forming images on both sides of the sheet is performed; an image forming unit that forms an image on a second side of the sheet based on first side image data and forms an image on a third side of the sheet based on second side image data; a controller that starts the image forming process upon receiving print data to be printed on specific paper, and inverts a sheet fed from a sheet feeding unit once or more; and a converting unit that, when the sheet fed from the sheet feeding unit is the specific paper, converts the first side print data which is received to be printed on the specific paper into N-th side image data where N≥2 and transfers the N-th side image data to the image forming unit.

An image forming apparatus includes an image forming device that forms an image on a recording medium and circuitry that controls the image forming device. The image forming device forms an invisible image with an invisible material on the recording medium and forms a visible image with a visible material on the invisible image. Each of first and second adhesion amounts includes respective adhesion amounts of the visible material and the invisible material per unit area in a portion, in which the visible image is formed on the invisible image, of the composite image. The second adhesion amount is smaller than the first adhesion amount. The controller adjusts the amount of the invisible material included in the second adhesion amount to be smaller than that included in the first adhesion amount, to cause the image forming device to form the image according to the second adhesion amount.

A belt transfer type multi-function device includes a control device performing controlling such that an image to be printed on paper already caught between a transfer roller and the belt roller is printed, and if printing should not be performed on a next paper, movement of the next paper is stopped on a transfer path before the next paper is positioned between the transfer roller and the belt roller, the image already transferred on the transfer belt is deleted in a state in which the next paper is stopped on the transfer path, and the next paper in a stopped state is ejected as a blank paper through a ejection port along the transfer path, so that the image already transferred to the transfer belt, which is to be printed on the next paper along the movement direction of paper, is not printed on the next paper.

An image forming apparatus includes an image forming device that forms an image on a recording medium and circuitry that controls the image forming device. The image forming device forms an invisible image with an invisible material on the recording medium and forms a visible image with a visible material on the invisible image. Each of first and second adhesion amounts includes respective adhesion amounts of the visible material and the invisible material per unit area in a portion, in which the visible image is formed on the invisible image, of the composite image. The second adhesion amount is smaller than the first adhesion amount. The controller adjusts the amount of the invisible material included in the second adhesion amount to be smaller than that included in the first adhesion amount, to cause the image forming device to form the image according to the second adhesion amount.

An image forming apparatus includes an image forming device that forms an image on a recording medium and circuitry that controls the image forming device. The image forming device forms an invisible image with an invisible material on the recording medium and forms a visible image with a visible material on the invisible image. Each of first and second adhesion amounts includes respective adhesion amounts of the visible material and the invisible material per unit area in a portion, in which the visible image is formed on the invisible image, of the composite image. The second adhesion amount is smaller than the first adhesion amount. The controller adjusts the amount of the invisible material included in the second adhesion amount to be smaller than that included in the first adhesion amount, to cause the image forming device to form the image according to the second adhesion amount.

A belt transfer type multi-function device includes: a control device performing controlling such that an image to be printed on paper already caught between a transfer roller and the belt roller is printed, and if printing should not be performed on a next paper, movement of the next paper is stopped on a transfer path before the next paper is positioned between the transfer roller and the belt roller, the image already transferred on the transfer belt is deleted in a state in which the next paper is stopped on the transfer path, and the next paper in a stopped state is ejected as a blank paper through a ejection port along the transfer path, so that the image already transferred to the transfer belt, which is to be printed on the next paper along the movement direction of paper, is not printed on the next paper.

Described herein is a security LEP ink composition comprising an absorber, a resin; and a carrier liquid for printing a security image.