Abstract: An ink is circulated in a circulation path including a supply sub-tank, a discharge head and a collection sub-tank in a head unit. If the amount of the ink in the head unit decreases, the ink stored in the buffer tank is replenished to the head unit. On the other hand, in a first non-replenishment time during which the ink is not replenished, the ink is circulated through the buffer tank, the collection sub-tank and the supply sub-tank in this order. Thus, a temperature fluctuation of the replenishment ink stored in the buffer tank is suppressed. As a result, even if the ink is replenished to the head unit from the buffer tank, physical properties, particularly a viscosity, of the ink do not largely vary.

Abstract: An ink is circulated in a circulation path including a supply sub-tank, a discharge head and a collection sub-tank in a head unit. If the amount of the ink in the head unit decreases, the ink stored in the buffer tank is replenished to the head unit. On the other hand, in a first non-replenishment time during which the ink is not replenished, the ink is circulated through the buffer tank, the collection sub-tank and the supply sub-tank in this order. Thus, a temperature fluctuation of the replenishment ink stored in the buffer tank is suppressed. As a result, even if the ink is replenished to the head unit from the buffer tank, physical properties, particularly a viscosity, of the ink do not largely vary.

Abstract: A printing system includes a coating device, a printing device, and a controller. The coating device applies a processing liquid to a base material by bringing a coating roller with the processing liquid adhering thereto into contact with the transported base material. The printing device performs printing on a surface of the base material to which the processing liquid has been applied. The controller includes a contact-start-position identifier, an inappropriate-printing-area setter, and a print controller. The contact-start-position identifier identifies a contact start position of the base material in which the coating roller and the base material start to come in contact with each other. The inappropriate-printing-area setter sets, as the inappropriate printing area, an area of the base material that has a predetermined length in a transport direction from the contact start position. The print controller stops the printing device from performing printing on the inappropriate printing area.

Abstract: The ratio of the rotation speed Nr of the take-up roller (take-up rotation speed) and the rotation speed Nu of the feeding roller (feeding rotation speed) is used. That is, knowledge that the roll diameter Drr of the sheet S taken up on the take-up roller is given by a function using the ratio of the rotation speeds Nr and Nu as a variable was obtained. Accordingly, the roll diameter Drr is computed from this ratio.

Abstract: The cleaning liquid is supplied to the head facing flat surface, and the dummy flat surface of the dummy block facing the head facing flat surface contacts the cleaning liquid. This causes the cleaning liquid to be spread on the head facing flat surface by the dummy flat surface. The cleaning liquid spread on the head facing flat surface is sucked through the suction holes of the suction block. The suction holes can be cleaned by the cleaning liquid passing through the suction holes according to suction. On this occasion, the ink supplied to the head facing flat surface is removed through the suction holes of the suction block. The suction holes have both a function of removing the ink from the discharge heads H and a function of removing the cleaning liquid from the head facing flat surface.

Abstract: An ink is circulated in a circulation path including a supply sub-tank, a discharge head and a collection sub-tank in a head unit. If the amount of the ink in the head unit decreases, the ink stored in the buffer tank is replenished to the head unit. On the other hand, in a first non-replenishment time during which the ink is not replenished, the ink is circulated through the buffer tank, the collection sub-tank and the supply sub-tank in this order. Thus, a temperature fluctuation of the replenishment ink stored in the buffer tank is suppressed. As a result, even if the ink is replenished to the head unit from the buffer tank, physical properties, particularly a viscosity, of the ink do not largely vary.