BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a liquid ejecting head and a liquid ejecting apparatus.

Description of the Related Art

Recently, for a liquid ejecting head such as an inkjet print head, there is proposed a configuration of circulating liquid with an element substrate having ejecting elements arranged thereon to stabilize a liquid ejection state of the ejecting elements. Japanese Patent No. 5731657 discloses a configuration in which a plurality of types of liquids are supplied to the same element substrate through individual flow paths to perform an ejecting operation in accordance with ejection data by each of the ejecting elements, and liquid that has not been consumed in the ejecting operation is collected.

In a case where a plurality of types of liquids are ejected from the same element substrate, the flow paths for supplying/collecting liquids to/from the ejecting elements are arranged in different positions for each type of liquid. In this case, if the length or shape of the flow path, the height in a vertical direction in which the flow path is arranged, and the like are different for each type of liquid, the liquids may have different flow path resistances, causing variations in their ejection states, which makes it difficult for all types of liquids to have a common ejection design.

Providing regulators upstream and downstream of the element substrate as disclosed in Japanese Patent No. 5731657 may allow adjustment of a pressure in the flow path for each type of liquid. In this case, however, it is needed to prepare separate regulators for each liquid, which may cause increase in cost.

SUMMARY OF THE INVENTION

The present invention has been made to solve the above problem. Therefore, an object of the present invention is to have an equal flow path resistance among different liquids, in the configuration of supplying, ejecting, and collecting a plurality of types of liquids through individual flow paths using the same element substrate.

According to a first aspect of the present invention, there is provided a liquid ejecting head comprising: an element substrate having ejecting elements for ejecting a first liquid and ejecting elements for ejecting a second liquid arrayed thereon; and a laminated flow path member formed by laminating a plurality of layers, the laminated flow path member having a supply flow path for individually supplying the first liquid and the second liquid to the element substrate and a collection flow path for individually collecting the first liquid and the second liquid from the element substrate, wherein the supply flow path includes in part a first common supply flow path for leading the first liquid to positions corresponding to a plurality of the element substrates and a second common supply flow path for leading the second liquid to positions corresponding to the plurality of element substrates, the first common supply flow path and the second common supply flow path being formed in a same layer of the plurality of layers forming the laminated flow path member, and the collection flow path includes in part a first common collection flow path for horizontally collecting the first liquid from positions corresponding to the plurality of element substrates and a second common collection flow path for horizontally collecting the second liquid from positions corresponding to the plurality of element substrates, the first common collection flow path and the second common collection flow path being formed in a same layer of the plurality of layers forming the laminated flow path member.

According to a second aspect of the present invention, there is provided a liquid ejecting head comprising: first and second element substrates each having an ejection energy generating element for ejecting a first liquid and an ejection energy generating element for ejecting a second liquid; and a laminated flow path member having a supply flow path for supplying a liquid to the first and second element substrates and a collection flow path for collecting a liquid from the first and second element substrates, wherein the laminated flow path member includes a common supply flow path layer having a common supply flow path for supplying a liquid to the first and second element substrates and a common collection flow path layer having a common collection flow path for collecting a liquid from the first and second element substrates.

According to a third aspect of the present invention, there is provided a liquid ejecting apparatus comprising: a buffer tank for individually reserving a first liquid and a second liquid; a liquid ejecting head for ejecting the first liquid and the second liquid; a first circulation flow path for supplying the first liquid and the second liquid from the buffer tank to the liquid ejecting head; a second circulation flow path for collecting, into the buffer tank, the first liquid and the second liquid that have not been ejected from the liquid ejecting head; and a pump provided midstream in the second circulation flow path, for individually causing the first liquid and the second liquid to flow between the buffer tank and the liquid ejecting head, wherein the liquid ejecting head includes an element substrate having ejecting elements for ejecting the first liquid and ejecting elements for ejecting the second liquid arrayed thereon, a laminated flow path member formed by vertically laminating a plurality of layers each having a horizontal surface, the laminated flow path member having a supply flow path for individually supplying the first liquid and the second liquid to the element substrate and a collection flow path for individually collecting the first liquid and the second liquid from the element substrate, the supply flow path includes in part a first common supply flow path for horizontally leading the first liquid to positions corresponding to a plurality of the element substrates and a second common supply flow path for horizontally leading the second liquid to positions corresponding to the plurality of element substrates, the first common supply flow path and the second common supply flow path being formed in a same layer of the plurality of layers forming the laminated flow path member, and the collection flow path includes in part a first common collection flow path for horizontally collecting the first liquid from positions corresponding to the plurality of element substrates and a second common collection flow path for horizontally collecting the second liquid from positions corresponding to the plurality of element substrates, the first common collection flow path and the second common collection flow path being formed in a same layer of the plurality of layers forming the laminated flow path member.

Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.

