Pressure-responsive particles include pressure-responsive base particles and first inorganic oxide particles, in which the pressure-responsive base particles contain a styrene-based resin which contains styrene and other vinyl monomers as polymerization components and a (meth)acrylic acid ester-based resin which contains at least two kinds of (meth)acrylic acid esters as polymerization components and in which a mass ratio of the (meth)acrylic acid esters to all polymerization components is 90% by mass or higher, Db/Da which is a ratio of a number average particle diameter Db of the first inorganic oxide particles to a number average particle diameter Da of the pressure-responsive base particles is 0.05 or higher and 0.25 or lower, the pressure-responsive particles have at least two glass transition temperatures, and a difference between a lowest glass transition temperature and a highest glass transition temperature is 30 C. or higher.

Provided is a puncher having activating/inactivating switch for post-processing function. The puncher prevents undesirable post processing even if the switch indicates activation of the post processing. When a puncher which is registered in the image forming apparatus is attached to the puncher, the puncher obtains information indicating whether or not to the post processing using a punch die is activated or not. When the obtained information indicates that the post processing using the punch die is inactivated, even if the switch indicates activation of the post processing, the post processing is not performed.

A sheet processing apparatus includes a conveyor, a first folding roller, a second folding roller, a return conveyance passage, and a third folding roller. The conveyor conveys a sheet along a main conveyance passage in a conveyance direction. The second folding roller facing the first folding roller across the main conveyance passage conveys the sheet by a first conveyance amount. The return conveyance passage having a curvature is branched from the main conveyance passage at a branching position and is merged to the main conveyance passage at a merging position. The third folding roller facing the second folding roller across the return conveyance passage conveys the sheet by a second conveyance amount smaller than the first conveyance amount of the second folding roller. The second folding roller is on an outer peripheral side and the third folding roller is on an inner peripheral side of the return conveyance passage.

An enclosing device includes an envelope conveyance path, an envelope loader, an envelope-position restrictor, and an envelope-position adjuster. The envelope conveyance path conveys an envelope to an enclosing position at which an enclosure is enclosed into the envelope. The envelope loader loads the envelope to be supplied to the envelope conveyance path. The envelope-position restrictor restricts a loaded position of the envelope in the envelope loader. The envelope-position adjuster adjusts a position of the envelope with respect to a conveyance direction of the envelope while maintaining a state in which the envelope-position restrictor restricts the loaded position of the envelope.

A sheet bonding apparatus includes an applying portion, a fixing portion, a folding portion, and a bonding portion including a heating member and a non-heating member which oppose to each other and which are for bonding the sheet by nipping the sheet therebetween. Two regions opposing to each other when the folding portion folds a sheet are a first region and a second region. In a case that when the bonding portion bonds the folded sheet, the first region is positioned on a heating member side and the second region is positioned on a non-heating member side, the applying portion applies the powdery adhesive so that an application amount of the powdery adhesive on the sheet is smaller in the first region than in the second region.

A sheet folding apparatus includes a sheet folder and circuitry. The sheet folder includes a sheet folding part, and an additional folding part to reinforce a folding portion in the sheet. The circuitry is to control the sheet folder to form and reinforce the folding portion in the sheet; acquire, before completion of a folding operation, first sheet information of the sheet and first folding information indicating a type of the folding operation on the sheet; run a trained model obtained through machine learning executed using second sheet information of a training sheet, second folding information indicating a type of the folding operation on the training sheet, and multiple training datasets including a folding evaluation value; estimate the folding evaluation value after the completion of the folding operation on the sheet; and determine the type of a control content in the folding operation, based on the folding evaluation value.

A control portion stops driving a developer carrying member at the end of a development process for a preceding image to be printed on the last sheet of a preceding copy and starts driving the developer carrying member when performing a development process for a subsequent image to be printed on the first sheet of the subsequent copy. Regardless of the length of a development driving suspension period after stopping driving the developer carrying member following the end of the development process for the preceding image until starting driving the developer carrying member to perform the development process for the subsequent image, the control portion maintains suspension of the driving of the developer carrying member during the development driving suspension period.

A sheet processing apparatus includes: a folding device that folds a sheet bundle which is formed of multiple sheets stacked on each other; and a stapleless binding device including a binding unit that binds the sheet bundle at a position of a portion near a fold line without using a staple, the fold line being formed as a result of the folding device folding the sheet bundle.

An image forming apparatus includes a conveyor that conveys a sheet, an image forming unit that forms an image on the sheet, a post-processing unit folds the sheet after the image is formed, and a controller that receives a selection including either a first print mode or a second print mode. The controller controls the image forming apparatus to print a document including a first manuscript serving as a first page of the document and a second manuscript which has a manuscript size different from the first manuscript. In response to the selection of the first print mode, the controller controls an orientation of the first manuscript to be the same as an orientation of the second manuscript. In response to the selection of the a second print mode, the controller controls the orientation of the first manuscript to be different from the orientation of the second manuscript.

An image forming apparatus accepts a selection of a first mode for forming a toner image for adhering foil onto a sheet via the toner image and an input of information relating to post-processing. The apparatus forms the toner image on the sheet. The apparatus displays a warning on a display according to the information relating to the post-processing, when the first mode is selected by the input unit.