A method for assessing the condition and improving the printing quality of printing nozzles in printheads of an inkjet printing machine includes printing a nozzle test chart formed of a specific number of horizontal rows of equidistant vertical lines printed periodically underneath one another, with only every n.sup.th printing nozzle contributing to the test chart in every row of the test chart and n corresponding to a different number between one and the specific number of horizontal rows, recording and digitizing the test chart and analyzing the test chart regarding the condition of the contributing nozzles by using a computer. The nozzles printing horizontal lines between the horizontal rows complementing the equidistant vertical lines to form quadrangular objects used by the computer to analyze the condition of the contributing nozzles. Measures are taken to improve the printing quality of the nozzles depending on the condition of the contributing nozzles.

According to the present invention, a printing apparatus is provided, the printing apparatus comprises a printhead including an ink discharge surface on which plurality of orifices for discharging ink are arranged and configured to print an image, a cap configured to cap the ink discharge surface, and a supply unit configured to selectively supply one of a plurality of types of liquids into the cap.

The printed article includes a medium having a specular reflective layer, a first line composed of a first color formed at the medium, a second line formed at the medium in a second color and formed parallel to the first line, and a prism layer formed onto at least the first line, wherein when the medium is divided into a first region, a second region, and a third region that are continuous in parallel, the first line is disposed in any one region of the first region, the second region, and the third region, the second line is disposed in any one region other than the region where the first line was formed, the prism layer is disposed across two contiguous regions including the region formed with the first line, and the section of the prism layer has a shape of a portion of the non-circular arc approximating the ellipse.

A liquid discharge apparatus includes a liquid discharge head including a nozzle face including a nozzle configured to discharge a liquid, a head cap configured to cover the nozzle face of the liquid discharge head, a buffer tank disposed downstream from the head cap in a direction of collection of the liquid from the liquid discharge head and configured to temporarily store the liquid, a communication passage coupling the head cap and the buffer tank, and a heater configured to heat the liquid stored in the buffer tank. The quid discharge apparatus further includes a heat source configured to generate heat and a heat introduction passage coupling the heat source with the buffer tank, to introduce exhaust heat from the heat source into the buffer tank.

A printer control unit controls a fan, based on an acquired reference temperature and an output of a sensor, to cause a temperature of a platen drum or a temperature of a sheet supported by the platen drum to be the reference temperature. Specifically, at step S100, the printer control unit acquires a type of the printing medium to be used for printing, acquires the reference temperature at step S110, and at step S150, controls an operating state of the fan, based on the temperature of the platen drum output by the sensor, such that the temperature of the platen drum becomes the reference temperature acquired at step S110. As a result, a temperature increase of the platen drum becomes substantially saturated at the targeted reference temperature.

A recording-head position adjustment mechanism adjusts a position of a recording head that discharges liquid droplets. The recording-head position adjustment mechanism includes a supporting member and a discharge angle adjuster. The supporting member includes an upper support to support an upper portion of the recording head and a lower support to support a lower portion of the recording head. The discharge angle adjuster swings the lower portion around the upper portion as a fulcrum to adjust a discharge direction of the liquid droplets from the recording head.

The printed article includes a medium having a specular reflective layer, a first line composed of a first color formed at the medium, a second line formed at the medium in a second color and formed parallel to the first line, and a prism layer formed onto at least the first line, wherein when the medium is divided into a first region, a second region, and a third region that are continuous in parallel, the first line is disposed in any one region of the first region, the second region, and the third region, the second line is disposed in any one region other than the region where the first line was formed, the prism layer is disposed across two contiguous regions including the region formed with the first line, and the section of the prism layer has a shape of a portion of the non-circular arc approximating the ellipse.

A discharge unit includes a head configured to discharge a liquid, a head mount to which the head is detachably attachable, and a holder configured to hold the head mount. The head mount includes multiple rotation mechanisms on multiple places of the head mount in a longitudinal direction of the head mount, and the holder is configured to rotatably and independently hold the multiple places of the head mount with the rotation mechanisms.

A discharge unit includes a head configured to discharge a liquid, a head mount to which the head is detachably attachable, and a holder configured to hold the head mount. The head mount includes multiple rotation mechanisms on multiple places of the head mount in a longitudinal direction of the head mount, and the holder is configured to rotatably and independently hold the multiple places of the head mount with the rotation mechanisms.

A liquid ejecting apparatus includes: a first head disposed such that an arrangement angle is a first angle; a second head disposed such that an arrangement angle is a second angle, which is greater than the first angle; a first circulation mechanism circulating liquid between a first reservoir and the first head; a second circulation mechanism circulating liquid between a second reservoir and the second head; and a control unit controlling the first and the second circulation mechanisms. The control unit performs circulation cleaning, in which the liquid is circulated, on multiple heads including the first head and the second head. The amount of the liquid circulating through the first head during the circulation cleaning is a first amount, and the amount of the liquid circulating through the second head during the circulation cleaning is a second amount that is greater than the first amount.