Droplet discharge head, manufacturing method thereof, and droplet discharge apparatus
View Patent ↗A droplet discharge head includes a nozzle substrate having a nozzle opening for discharging a liquid as a droplet; a flow path substrate having a flow path for the liquid, the flow path communicating with the nozzle opening; and a diaphragm constituting a wall surface of the flow path. The nozzle substrate, the flow path substrate, and the diaphragm are bonded together in layers using an adhesive, and a liquid-resistant film resistant to the liquid is continuously formed on surfaces of the nozzle substrate, the flow path substrate, and the diaphragm, the surfaces being in contact with the liquid.
1. A droplet discharge head, comprising:
a nozzle substrate having a nozzle opening for discharging a liquid as a droplet;
a flow path substrate having a flow path for the liquid, the flow path communicating with the nozzle opening; and
a diaphragm constituting a wall surface of the flow path, wherein
the nozzle substrate, the flow path substrate, and the diaphragm are bonded together in layers using an adhesive, and
a liquid-resistant film resistant to the liquid is continuously formed on surfaces of the nozzle substrate, the flow path substrate, and the diaphragm, the surfaces being in contact with the liquid.
2. The droplet discharge head according to claim 1 , further comprising:
a piezoelectric element for changing, via the diaphragm, a volume of a pressure chamber provided in the flow path; and
a casing holding the piezoelectric element and having a liquid supply path for supplying the liquid to the flow path, wherein
the casing is bonded to the diaphragm using an adhesive, and
a surface of the casing facing the liquid supply path is covered with the liquid-resistant film continuously formed from the surface of the diaphragm in contact with the liquid.
3. The droplet discharge head according to claim 1 , wherein
the liquid-resistant film is formed of a lyophilic material.
4. The droplet discharge head according to claim 1 , wherein
the liquid-resistant film is formed of a liquid-repellent material.
5. The droplet discharge head according to claim 1 , wherein
a thickness of the liquid-resistant film is equal to or larger than a thickness of one molecule layer and equal to or less than 1 μm.
6. A droplet discharge apparatus comprising
the droplet discharge head according to claim 1 .
7. A method for manufacturing a droplet discharge head, comprising:
(a) bonding together a nozzle substrate, a flow path substrate, and a diaphragm using an adhesive, the nozzle substrate having a nozzle opening for discharging a liquid as a droplet, the flow path substrate having a flow path for the liquid, the flow path communicating with the nozzle opening, the diaphragm constituting a wall surface of the flow path,;
(b) filling the flow path with a material liquid for a liquid-resistant film; and
(c) discharging the material liquid from the flow path and heating and then drying the material liquid adhering to surfaces of the nozzle substrate, the flow path substrate, and the diaphragm so that a liquid-resistant film resistant to the liquid is continuously formed on the surfaces, the surfaces being in contact with the liquid.
8. The method for manufacturing a droplet discharge head according to claim 7 , wherein
in step (a), a casing holding a piezoelectric element and having a liquid supply path for supplying the liquid to the flow path is bonded to the diaphragm using an adhesive, the piezoelectric element changing, via the diaphragm, a volume of a pressure chamber provided in the flow path,
in step (b), the flow path and the liquid supply path are filled with the material liquid, and
in step (c), the material liquid adhering to a surface of the casing is heated and then dried so that the liquid-resistant film continuing from a surface of the diaphragm to a surface of the casing is formed, the surface of the diaphragm facing the flow path, the surface of the casing facing the liquid supply path.
9. The method for manufacturing a droplet discharge head according to claim 7 , wherein
in step (b), the material liquid is a material liquid containing Si.
10. The method for manufacturing a droplet discharge head according to claim 7 , wherein
in step (b), the material liquid is any one of a fluoro material liquid, a silicone material liquid, and an organopolysiloxane material liquid containing fluorine.