Image forming apparatus and sheet bonding apparatus

An image forming apparatus for forming a toner image on a sheet and forming a booklet with a plurality of sheets bonded together, the image forming apparatus comprising:

• an image forming portion configured to form the toner image and a bonding toner pattern on the sheet;
• and
• a bonding portion configured to bond sheets together via the bonding toner pattern by pressurizing and heating the plurality of sheets,
• wherein the image forming portion is configured to form the bonding toner pattern on both surfaces of each sheet of the booklet, except a first sheet of the booklet and a last sheet of the booklet, the surfaces including a first surface and a second surface backside of the first surface,
• wherein the image forming portion is configured to form the toner image in an image region on the sheet by using toner, and form the bonding toner pattern in a bonding region on the sheet different from the image region by using the toner,
• wherein the image forming portion is configured to form the bonding toner pattern of a solid pattern on the first surface and on the second surface such that:
• a toner amount per unit area in the bonding region on the first surface is different from a toner amount per unit area in the image region on the first surface, and
• a toner amount per unit area in the bonding region on the second surface is different from a toner amount per unit area in the image region on the second surface.

A sheet bonding apparatus for forming a booklet with a plurality of sheets bonded together, the sheet bonding apparatus comprising:

• an application portion configured to form a bonding toner pattern on a sheet by using toner;
• and
• a bonding portion including a pressurizing member and configured to bond sheets together via the bonding toner pattern by performing a bonding operation of pressurizing and heating a plurality of sheets by the pressurizing member,
• wherein the bonding portion is configured to, in a state in which a succeeding sheet is stacked on a plurality of sheets that has been bonded in a previous bonding operation, perform a next bonding operation to bond a first surface of an uppermost sheet of the bonded plurality of sheets to a second surface of the succeeding sheet opposing the first surface, the next bonding operation and the previous bonding operation each being the bonding operation, and
• wherein the application portion is configured to form the bonding toner pattern of a solid pattern on the first surface and on the second surface, such that an amount of the toner per unit area within the bonding toner pattern on the first surface is smaller than an amount of the toner per unit area within the bonding toner that the application portion applies pattern on the second surface.

An image forming apparatus for forming a toner image on a sheet and forming a booklet with a plurality of sheets bonded together, the image forming apparatus comprising:

• an image forming portion configured to form the toner image and a bonding toner pattern on the sheet;
• and
• a bonding portion including a pressurizing member and configured to bond sheets together via the bonding toner pattern by performing a bonding operation of pressurizing and heating the plurality of sheets by the pressurizing member,
• wherein the bonding portion is configured to, in a state in which a succeeding sheet is stacked on a plurality of sheets bonded in a previous bonding operation, perform a next bonding operation to bond a first surface of an uppermost sheet of the bonded plurality of sheets to a second surface of the succeeding sheet opposing the first surface, the next bonding operation and the previous bonding operation each being the bonding operation, and
• wherein the image forming portion is configured to form the bonding toner pattern of a solid pattern on the first surface and on the second surface, such that a toner density of the bonding toner pattern on the first surface is lower than a toner density of the bonding toner pattern on the second surface.

An image forming apparatus for forming a toner image on a sheet and forming a booklet with a plurality of sheets bonded together, the image forming apparatus comprising:

• an image forming portion configured to form the toner image and a bonding toner pattern on the sheet;
• and
• a bonding portion including a pressurizing member and configured to bond sheets together via the bonding toner pattern by performing a bonding operation of pressurizing and heating the plurality of sheets by the pressurizing member,
• wherein the bonding portion is configured to, in a state in which a succeeding sheet is stacked on a plurality of sheets bonded in a previous bonding operation, perform a next bonding operation to bond a first surface of an uppermost sheet of the bonded plurality of sheets to a second surface of the succeeding sheet opposing the first surface, the next bonding operation and the previous bonding operation each being the bonding operation, and
• wherein the image forming portion is configured to form the bonding toner pattern of a solid pattern on the first surface and on the second surface, such that a thickness of a layer of the bonding toner pattern on the first surface is smaller than a thickness of a layer of the bonding toner pattern on the second surface.