Foil images are formed simultaneously with color toner images on a receiver material. One or more color toner latent images are formed on the receiver material using dry color toners. Each dry color toner has a (a) polymeric resin, a (b) pigment colorant, and a (c) wax that has a melting temperature defined as T.sub.color. A foiling latent image is formed using a dry foiling toner that has a (a′) polymeric resin and a (c′) wax that has a melting temperature defined as T.sub.foiling. The foiling latent image is in an area that is different from the color image areas and T.sub.foiling is less than T.sub.color by at least 15° C. All toners are simultaneously fixed in a fuser oil-free fixing operation. A printing foil can be brought into intimate contact with the fused foiling toner at a foiling temperature (FT) that is greater than T.sub.foiling but less than T.sub.color.

Metallic paper for electrophotography is provided. The metallic paper comprises a substrate, a metallic luster layer over the substrate, and a polyester at a surface of the metallic paper. A ratio B/A is 0.90 or less, where A and B respectively represent peak area A and a peak area B in an infrared spectrum of the metallic paper obtained by an ATR method with a crystal of Ge, an incident angle of 45°, and one time of reflection. The wavenumber range of peak area A ranges from 1709.586 to 1741.406 cm.sup.−1, the wavenumber range of peak area. B ranges from 1630,519 to 1670.052 cm.sup.1, and a baseline wavenumber range of the peaks ranges from 1593.878 to 1850.364 cm.sup.−1.

An image formation apparatus includes: a fixing belt wound on a plurality of support rollers including a first pressure applying roller; a second pressure applying roller applying a pressure to the first pressure applying roller and thus forming a nip portion N; a tension modifying mechanism adjusting a tension; a contact area adjustment mechanism adjusting a downstream contact area, which is a contact area of the fixing belt in contact with the first pressure applying roller that is located downstream of the nip portion N; a sheet information obtainer; and a controller controlling an operation of the tension modifying mechanism and an operation of the contact area adjustment mechanism. When sheet information indicates embossed paper, the controller adjusts the operation of the tension modifying mechanism and the operation of the contact area adjustment mechanism to reduce a tension exerted to the fixing belt and also reduce the downstream contact area.

Metallic paper for electrophotography is provided. The metallic paper comprises a substrate, a metallic luster layer over the substrate, and a polyester at a surface of the metallic paper. A ratio B/A is 0.90 or less, where A and B respectively represent a peak area A and a peak area B in an infrared spectrum of the metallic paper obtained by an ATR method with a crystal of Ge, an incident angle of 45°, and one time of reflection. The peak area A ranges from 1709.586 to 1741.406 cm.sup.−1, the peak area B ranges from 1630.519 to 1670.052 cm.sup.−1, and a baseline of the peaks ranges from 1593.878 to 1850.364 cm.sup.−1.

A sheet processing apparatus includes circuitry configured to acquire a size of a two-ply sheet, in which two sheets are bonded together at one end, and a size of an insertion sheet; and control a sheet processing operation based on the size of the two-ply sheet and the size of the insertion sheet. The sheet processing operation includes inserting the insertion sheet in the two-ply sheet.

A sheet separation device configured to separate a two-ply sheet, in which two sheets are bonded together at a portion, includes a rotator, a nipping member disposed opposite the rotator and configured to nip the two-ply sheet with the rotator, a conveyor configured to convey the two-ply sheet between the rotator and the nipping member, and a winding member disposed adjacent to the rotator. The conveyor conveys the two-ply sheet with a bonded portion of the two-ply sheet being an upstream end or a downstream end of the two-ply sheet in a conveyance direction of the two-ply sheet. The winding member winds the two-ply sheet around the rotator, to create a difference in winding circumferential length between the two sheets and separate the two sheets. The sheet separation device further includes control circuitry configured to adjust a winding amount of the two-ply sheet around the rotator.

A stereoscopic image forming method forms a color stereoscopic image on a recording medium having a thermal expansion property. The stereoscopic image forming method includes the steps of: fixing a color image on the thermally expandable recording medium using a color material; and irradiating the fixed color image with light of a light source having a maximum emission wavelength in a wavelength range of 280 to 780 nm. This light is absorbed by a compound contained in the color material to generate heat of the compound.

An image forming method for an image forming apparatus having a fixing rotator and a pressure rotator opposite the fixing rotator includes transferring white toner and color toner onto a surface of a metallic sheet. The metallic sheet has a thermal conductivity of 0.34 W/m.Math.K or less as measured by hot-wire method. The transferring process forms an unfixed color toner layer layered on an unfixed white toner layer on the metallic sheet. Further, the method includes conveying the metallic sheet, with the surface on which the white toner layer and the color toner layer being transferred facing the fixing rotator, between the fixing rotator heated and the pressure rotator to fix the white toner layer and the color toner layer onto the metallic sheet.

An image forming apparatus includes a first toner image forming unit, a second toner image forming unit, and a transfer section. The first toner image forming unit forms a first toner image with use of a first toner. The first toner has a complex viscosity that falls within a range from 625 Pascal-seconds to 3860 Pascal-seconds, both inclusive, at a temperature of 100 degrees centigrade. The second toner image forming unit forms a second toner image with use of a second toner. The transfer section transfers the first toner image onto a print medium, and transfers the second toner image onto the print medium in a region that overlaps a portion or all of a region where the first toner image has been transferred. The print medium includes a polymer compound.

Provided is a stereoscopic image forming method for forming a color stereoscopic image on a recording medium having a thermal expansion property, the stereoscopic image forming method including the steps of: fixing a color image on the thermally expandable recording medium using a color material; and irradiating the fixed color image with light of a light source having a maximum emission wavelength in a wavelength range of 280 to 780 nm that is absorbed by a compound contained in the color material to generate heat of the compound.