An inkjet recording apparatus configured to perform recording operation by ejecting ink at least from a first recording head, includes an ink tank configured to contain the ink to be supplied to the first recording head, a tube configured to connect the first recording head and the ink tank, and a carriage including a first mounting portion on which the first recording head is mounted, a second mounting portion on which a second recording head is detachably mounted, and a contact portion electrically connected to the second recording head, and configured to reciprocate. A protection member protecting the contact portion can be detachably mounted on the second mounting portion.

An information processing system includes a storage portion that stores a learned model obtained by performing machine learning on a maintenance condition for a print head based on a data set in which ink flow path inside information indicating a state of an ink flow path of the print head, nozzle surface image information obtained by photographing a nozzle plate surface of the print head, and maintenance information of the print head are associated with each other, an acquisition portion that acquires the ink flow path inside information and the nozzle surface image information, and a processing portion that outputs the maintenance information based on the acquired ink flow path inside information, the acquired nozzle surface image information, and the learned model.

A liquid discharge apparatus includes a conveyance roller, a liquid discharge head, and a control device. The control device controls the head to discharge liquid onto a medium X times in the main scanning direction and Y times in the sub-scanning direction and controls the roller such that a position of a droplet on the medium discharged by an m-th discharge and a position of another droplet on the medium discharged by an (m+Y)-th discharge are same in the sub-scanning direction, where m is an integer not smaller than one and not greater than ((X−1)×Y). Where P is a circumferential length of the roller and L is a difference in a conveyance distance in the sub-scanning direction when the m-th discharge is compared with the (m+Y)-th discharge, the following relation is satisfied:
L=(n+(Δθ/2π))×P, where |π−Δθ|<60° and n is an integer.

A printing device is configured to be used simultaneously with other printing devices and includes: a print unit configured to print by ejecting ink from nozzles; a timekeeping unit configured to keep time; a storage configured to store a reference period for executing a nozzle maintenance operation, the reference period being initially set at an initial reference period; and a maintenance processor configured to: execute a nozzle maintenance operation each time the reference period passes based on the time kept by the timekeeping unit, change the reference period stored in the storage from the initial reference period to a changed reference period such that a timing of the nozzle maintenance operation differs from a timing of the nozzle maintenance operation of at least one of the other printing devices, and execute the nozzle maintenance operation after the changed reference period passes.

To provide an ink jet recording method capable of suppressing generation of image streaks and recording a high-quality image, when using a recording apparatus equipped with a line head. Provided is an ink jet recording method which records an image on a recording medium by using an ink jet recording apparatus equipped with a line head. In this method, the line head has a plurality of recording element substrates each having a nozzle array made up of a plurality of nozzles which eject an aqueous ink. The recording element substrates are arranged in the predetermined direction. An average temperature Te (° C.) of an aqueous ink ejected from terminal-portion nozzles constituting the terminal portion of the nozzle array and an average temperature Tc (° C.) of an aqueous ink ejected from center-portion nozzles constituting the center portion of the nozzle array satisfy the following relationship: Te>Tc.

A liquid discharge head includes a head body, a cover, a rib, and a sealer. The head body discharges liquid. The head body includes a frame. The cover is mounted on the frame of the head body. The rib is disposed at the frame along a peripheral surface of the cover. The sealer is disposed between the peripheral surface of the cover and a peripheral surface of the rib.

A device may be configured to check, via evaluation of resistance data of a cleaning sensor arranged on a print bar of an inkjet printing device, whether a cleaner for cleaning the one or more print heads of the print bar exhibits a negative effect. The state of a cleaner may be reliably and efficiently monitored via the installation of a cleaning sensor in a print bar.

An ink set where a droplet of ink is ejected in an amount of not less than 100 pL and not more than 5,000 pL. The ink set includes at least two inks including an ink A and an ink B and the ink set satisfies conditions 1 to 3 as measured, on a surface of a solid image with a 100% print duty which is printed on a polyester film using the ink A and the ink B, respectively, with respect to coordinates (L*.sub.A, a*.sub.A, b*.sub.A) of the ink A and coordinates (L*.sub.B, a*.sub.B, b*.sub.B) of the ink B in CIE L*a*b* color space.

A single-pass inkjet printer contains a track for guiding a printing medium in the Y direction, a plurality of printing head modules which are arranged one behind the other in the Y direction and a respective plurality of printing heads which extends in the X direction transversely over the track, and a printing region in which the printing head modules can be mounted in a respective printing position in an upright manner in the Z direction and in a reversibly insertable and removable manner along the Z direction. The single-pass inkjet printer further contains a storage region in which a number of printing head modules are mounted in a storage position in an upright manner substantially in the Z direction and in a reversibly insertable and removable manner along the Z direction. The printing heads of printing head modules set in the storage position are received in a protective cover.

A printing apparatus according to the present invention includes a plurality of ejection heads for ejecting liquid and a plurality of mist collection units configured to collect mist generated by the ejection heads that are disposed along a medium conveyance direction. The plurality of mist collection units include a first mist collection unit. The first mist collection unit is provided to be inclined to the upstream side of a medium conveyance direction with regard to a perpendicular line perpendicular to a floor. The first mist collection unit has a liquid retention part disposed at the upstream side than an ink mist suction hole.