A sheet binding processing apparatus including a processing tray, a sheet positioning device, a first binding device, a second binding device, a driving device which moves the second binding device to a binding position where the sheets positioned by the sheet positioning device are to be bound and to a retracting position for retracting to the outside of the sheets positioned by the sheet positioning device, and a controller which controls the driving device and causes the second binding device to be located at the retracting position when the first binding device binds sheets.

A binding device includes: an upper teeth portion having at least one teeth row that forms unevenness in a recording material bundle; a lower teeth portion having at least one teeth row that forms unevenness in the recording material bundle and being paired with the upper teeth portion; and at least one holding portion that holds the recording material bundle at a position different from a position where the upper teeth portion and the lower teeth portion have a binding function, when binding processing is performed by the upper teeth portion and the lower teeth portion.

A binding device includes: an upper teeth portion having at least one teeth row that forms unevenness in a recording material bundle; a lower teeth portion having at least one teeth row that forms unevenness in the recording material bundle and being paired with the upper teeth portion; and at least one holding portion that holds the recording material bundle at a position different from a position where the upper teeth portion and the lower teeth portion have a binding function, when binding processing is performed by the upper teeth portion and the lower teeth portion.

A medium processing apparatus includes a liquid applier, a crimper, a stapler, and circuitry. The liquid applier applies liquid to a liquid application position of a medium. The crimper presses and deforms at least a part to which the liquid is applied by the liquid applier, to bind a plurality of media including the medium to which the liquid is applied. The stapler performs stapling with a staple on a medium bundle in which the plurality of media is bound by the crimper. The circuitry controls operations of the crimper, the liquid applier, and the stapler, and selectively switches between first binding performed by the liquid applier and the crimper and second binding performed by only the stapler, in accordance with information on the medium or a binding position at which the medium bundle is bound by the crimper.

A medium processing apparatus includes a liquid applier, a crimper, a stapler, and circuitry. The liquid applier applies liquid to a liquid application position of a medium. The crimper presses and deforms at least a part to which the liquid is applied by the liquid applier, to bind a plurality of media including the medium to which the liquid is applied. The stapler performs stapling with a staple on a medium bundle in which the plurality of media is bound by the crimper. The circuitry controls operations of the crimper, the liquid applier, and the stapler, and selectively switches between first binding performed by the liquid applier and the crimper and second binding performed by only the stapler, in accordance with information on the medium or a binding position at which the medium bundle is bound by the crimper.

A manufacturing method of a staple-less binding unit that includes a first binding unit that has plural recesses and projections and a second binding unit that is arranged to face the first binding unit and has recesses and projections that fit to the recesses and the projections of the first binding unit and in which mediums are bound by being interposed between the first binding unit and the second binding unit in a thickness direction of the mediums includes forming the binding units with a die, adjusting center positions of projecting portions of the binding units formed by the die and removed from the die, and adjusting outer shapes of the projecting portions of which the center positions have been adjusted.

A binding unit is a binding unit used in staple-less binding in which mediums are bound by being interposed between binding units having plural recesses and projections in a thickness direction of a bundle of the mediums, in which, among the plural projections, a tip end of a projecting portion, which is at a central portion in an arrangement direction of the projections, protrudes further than a projecting portion disposed at a position different from the central portion.

A binding unit is a binding unit used in staple-less binding in which mediums are bound by being interposed between binding units having plural recesses and projections in a thickness direction of a bundle of the mediums, in which, among the plural projections, a tip end of a projecting portion, which is at a central portion in an arrangement direction of the projections, protrudes further than a projecting portion disposed at a position different from the central portion.

A set of thin foil surfaces configured to achieve a joint among the foil surfaces, the joint being arranged to be without discontinuity, comprising at least a first portion of surface dedicated to achieve the joint; pixelized type embossings on the first portion of surface; and at least a second portion of surface dedicated to achieve the joint. The second portion of surface is shaped to correspond to the first portion of surface for making the joint between the first portion of surface and the second portion of surface through contact.

A set of thin foil surfaces configured to achieve a joint among the foil surfaces, the joint being arranged to be without discontinuity, comprising at least a first portion of surface dedicated to achieve the joint; pixelized type embossings on the first portion of surface; and at least a second portion of surface dedicated to achieve the joint. The second portion of surface is shaped to correspond to the first portion of surface for making the joint between the first portion of surface and the second portion of surface through contact.