Bookbinding apparatus

A bookbinding apparatus comprising:

• A holding element that holds a bundle of text sheets into which a plurality of text sheets have been gathered with a back edge face of the bundle down by nipping at two side surfaces;
• an application roller that rotates, while being partially immersed in an adhesive agent, on a rotary shaft which is parallel with a top-bottom direction of the bundle of text sheets held by the holding element;
• a motive mechanism including a motive element for making a relative motion between the holding element and the application roller;
• and
• a control unit that controls the holding element, the application roller, and the motive mechanism in such a way as to bring the application roller in contact with the back edge face of the bundle in a plurality of positions, respectively, which have been set on the back edge face along a thickness direction perpendicular to the top-bottom direction of the bundle of text sheets, rotate the application roller in each of the positions, and apply the adhesive agent onto the back edge face of the bundle,
• wherein the control unit controls rotation of the application roller and the motive mechanism in such a way as to bring the application roller in contact with the back edge face of the bundle at a first position within a given central region set on the back edge face with respect to the thickness direction, rotate the application roller in a given first direction, and apply the adhesive agent onto the back edge face of the bundle;
• and in such a way that, after stopping the rotation of the application roller, while contacting the application roller and the back edge face of the bundle, the holding element and the application roller are relatively moved to bring the application roller in contact with the back edge face of the bundle at a second position set on the back edge face with respect to the thickness direction and rotate the application roller in the given first direction.