Sharp Kabushiki Kaisha Corporation

Takashi Goto

Hiroshi Ishii

Hisashi Yoshimura

Hirokazu Nakamura

Masaki Matsushita

Naozumi Ueno

An ink cartridge includes an ink containing section including an ink absorbing body made of a porous material for retaining ink. The ink cartridge satisfies 200&#x2266;N&#xb7;R&#x2266;320, where N is the cell density, expressed in the number of pores per inch, of the ink absorbing body before the ink absorbing body is contained in the ink containing section; and R is a compressibility, which is a volume ratio of the ink absorbing body when the ink absorbing body is contained in a compressed state in the ink containing section to the ink absorbing body before the ink absorbing body is contained in the ink containing section. With this configuration, it is possible to (1) preventing ink leakage that is caused when the ink cartridge is inserted or detached, (2) realize stable supply of the ink when continuous ejection is performed, and (3) achieve effective utilization of the ink cartridge volume, thereby realizing an ink cartridge and an image forming apparatus which provide design indices for the ink absorbing body in accordance with properties of the ink.

Ink cartridge and image forming apparatus

The present invention can reduce the amount of ink in an outlet-side space which is sucked together with gas, without making the thickness of an isolating member for separating the inside of the sub-tank into an inlet-side space and the outlet-side space in the horizontal direction extremely thin nor making an inflow channel for allowing the ink in the inlet-side space to flow into the outlet-side space extremely small. The present invention has an isolating member in the form of a plate for separating the inside of a sub-tank coupled to a recording head into an inlet-side space connected to a main-tank and an outlet-side space connected to the recording head, and an inflow channel in the form of a slit for increasing the ink level in the inlet-side space while allowing the ink in the inlet-side space to flow into the outlet-side space from the isolating member.

Recording apparatus

The invention offers an inkjet printer which does not produce defective prints when bubbles enter ink supply tube. There is provided an air trap in an ink supply tube near an ink delivery port of an ink tank. The air trap is a hollow rectangular parallelepiped with a flow passage length of Lx, a height of Lh as measured from the bottom of an ink flow to a highest part, and a width of W. On its downstream end, the air trap has an outlet having a height of Ly as measured from the bottom of an ink flow. The air trap has a bubble catching space above the outlet. The dimensions are determined so that bubbles float at least up to height Ly while passing through the flow passage of length Lx. When bubbles flow into the air trap, they float and are caught in the space of the air trap before reaching the outlet.

Growing community of inventors

Nara, Japan

Takashi Goto