A post-processing apparatus comprises a first processing tray on which fed paper is placed; a paper binding section configured to bind a plurality of sheets of paper stacked on the first processing tray into one bundle; a second processing tray which a plurality of paper bundles bound on the first processing tray are sequentially conveyed to and placed on; a paper bundle gluing section configured to coat glue at a given position of the top surface of a first paper bundle placed on the second processing tray before a second paper bundle is placed on the first paper bundle; a pressing section configured to press and bind the first paper bundle with the second paper bundle between which glue is coated; and a control section configured to control the timing for conveying the second paper bundle onto the first paper bundle after the glue is coated.

A post-processing apparatus comprises a first processing tray on which fed paper is placed; a paper binding section configured to bind a plurality of sheets of paper stacked on the first processing tray into one bundle; a second processing tray which a plurality of paper bundles bound on the first processing tray are sequentially conveyed to and placed on; a paper bundle gluing section configured to coat glue at a given position of the top surface of a first paper bundle placed on the second processing tray before a second paper bundle is placed on the first paper bundle; a pressing section configured to press and bind the first paper bundle with the second paper bundle between which glue is coated; and a control section configured to control the timing for conveying the second paper bundle onto the first paper bundle after the glue is coated.

A recording-medium binding device includes a first tooth row and a second tooth row. The first tooth row and the second tooth row to be engaged with the first tooth row cooperate with each other to pinch a recording medium batch. The first tooth row and the second tooth row include at least one first region and at least one second region adjacent to the at least one first region. When the first tooth row and the second tooth row are engaged with each other, teeth of the first tooth row and teeth of the second tooth row overlap one another in a tooth height direction by a first engagement overlapping amount in the at least one first region and by a second engagement overlapping amount in the at least one second region. The second engagement overlapping amount is larger than the first engagement overlapping amount.

A recording-medium binding device includes a first tooth row and a second tooth row. The first tooth row and the second tooth row to be engaged with the first tooth row cooperate with each other to pinch a recording medium batch. The first tooth row and the second tooth row include at least one first region and at least one second region adjacent to the at least one first region. When the first tooth row and the second tooth row are engaged with each other, teeth of the first tooth row and teeth of the second tooth row overlap one another in a tooth height direction by a first engagement overlapping amount in the at least one first region and by a second engagement overlapping amount in the at least one second region. The second engagement overlapping amount is larger than the first engagement overlapping amount.

A stapleless binding device includes a stapleless binding unit that performs a stapleless binding operation to form irregularities in a sheet stack by making forward and backward movements, a moving unit that relatively moves the stapleless binding unit or the sheet stack in a direction along one side of the sheet stack, and a holding unit that holds the sheet stack during the backward movement of the stapleless binding unit. The holding unit holds the sheet stack during the backward movement of the stapleless binding unit before the moving unit moves the stapleless binding unit or the sheet stack.

A stapleless binding device includes a stapleless binding unit that performs a stapleless binding operation to form irregularities in a sheet stack by making forward and backward movements, a moving unit that relatively moves the stapleless binding unit or the sheet stack in a direction along one side of the sheet stack, and a holding unit that holds the sheet stack during the backward movement of the stapleless binding unit. The holding unit holds the sheet stack during the backward movement of the stapleless binding unit before the moving unit moves the stapleless binding unit or the sheet stack.

A recording-medium binding device includes a first tooth row including plural teeth and a second tooth row including plural teeth. The first and second tooth rows include a central region and end regions. The plural teeth of each of the first and second tooth rows include at least one tooth disposed in the central region and at least one tooth dispose in each of the end regions. In a process of pinching the recording medium batch, the at least one tooth of the first tooth row in the end region and the at least one tooth of the second tooth row in the end region pinch the recording medium batch earlier than the at least one tooth of the first tooth row in the central region and the at least one tooth of the second tooth row in the central region.

A recording-medium binding device includes a first tooth row including plural teeth and a second tooth row including plural teeth. The first and second tooth rows include a central region and end regions. The plural teeth of each of the first and second tooth rows include at least one tooth disposed in the central region and at least one tooth dispose in each of the end regions. In a process of pinching the recording medium batch, the at least one tooth of the first tooth row in the end region and the at least one tooth of the second tooth row in the end region pinch the recording medium batch earlier than the at least one tooth of the first tooth row in the central region and the at least one tooth of the second tooth row in the central region.

A binding device includes a first pressing member that presses a recording-medium stack from one surface side of the recording-medium stack, a second pressing member disposed at a position opposed to the first pressing member to press the recording-medium stack from the other surface side of the recording-medium stack, and a reduction part provided in at least one pressing member of the first pressing member and the second pressing member to reduce creases in recording media of the recording-medium stack in a binding operation when a number of the recording media in the recording-medium stack is smaller than a maximum number of recording media to be bound by the first pressing member and the second pressing member.

A binding apparatus includes: a first pressing member that presses a recording-medium stack from one side of the recording-medium stack; a second pressing member that faces the first pressing member and presses the recording-medium stack from the other side of the recording-medium stack; and a suppressing part provided in at least one of the first pressing member and the second pressing member, the suppressing part suppressing damage to recording media that may be caused when a recording-medium stack including a smaller number of sheets than the maximum number of sheets that can be bound is bound with the first pressing member and the second pressing member.