LIQUID EJECTING HEAD AND LIQUID EJECTING APPARATUS
According to one embodiment, a liquid ejecting head includes a piezoelectric member, electrodes, and a wiring substrate. The piezoelectric member has a plurality of piezoelectric elements formed of a piezoelectric material. The electrodes are formed on the piezoelectric member. The wiring substrate is joined to the electrodes by solder. The solder has a melting point of less than or equal to ½ of the Curie point of the piezoelectric material.
1 . A liquid ejecting head, comprising:
a piezoelectric member including a plurality of piezoelectric elements formed of a piezoelectric material;
a plurality of electrodes formed on the piezoelectric member; and
a wiring substrate joined to the plurality of electrodes by solder, wherein
a melting point of the solder is less than or equal to ½ of the Curie point of the piezoelectric material.
2 . The liquid ejecting head according to claim 1 , wherein the melting point of the solder is greater than a highest attainment temperature at a junction between the piezoelectric member and the wiring substrate during a liquid ejection operation.
3 . The liquid ejecting head according to claim 2 , wherein the highest attainment temperature is a peak temperature during the liquid ejection operation performed at a duty ratio of 100%.
4 . The liquid ejecting head according to claim 3 , wherein the solder is lead-free.
5 . The liquid ejecting head according to claim 2 , wherein the highest attainment temperature is in a range of 80° C. to 90° C. or less.
6 . The liquid ejecting head according to claim 1 , wherein the solder is lead-free.
7 . The liquid ejecting head according to claim 6 , wherein the piezoelectric material comprises lead zirconate titanate.
8 . The liquid ejecting head according to claim 6 , wherein the piezoelectric material comprises sodium potassium niobate.
9 . The liquid ejecting head according to claim 1 , wherein the piezoelectric material comprises lead zirconate titanate.
10 . The liquid ejecting head according to claim 1 , wherein the piezoelectric material comprises sodium potassium niobate.
11 . The liquid ejecting head according to claim 1 , wherein the piezoelectric elements comprise a plurality of piezoelectric layers stacked one on the other.
12 . The liquid ejecting head according to claim 11 , wherein the piezoelectric elements include internal electrode layers connected to the plurality of electrodes.
13 . The liquid ejecting head according to claim 12 , wherein the wiring substrate is a flexible printed circuit.
14 . The liquid ejecting head according to claim 12 , wherein the flexible printed circuit is directly soldered to piezoelectric elements.
15 . The liquid ejecting head according to claim 12 , wherein the wiring substrate is directly soldered to a lateral surface of the piezoelectric elements.
16 . The liquid ejecting head according to claim 11 , wherein the wiring substrate is a flexible printed circuit.
17 . The liquid ejecting head according to claim 1 , wherein the wiring substrate is a flexible printed circuit.
18 . A liquid ejecting apparatus, comprising:
a liquid ejecting head configured to eject droplets of a liquid, the liquid ejecting head including:
a piezoelectric member including a plurality of piezoelectric elements formed of a piezoelectric material;
a plurality of electrodes formed on the piezoelectric member; and
a wiring substrate joined to the plurality of electrodes by solder, wherein
a melting point of the solder is less than or equal to ½ of the Curie point of the piezoelectric material.
19 . The liquid ejecting apparatus according to claim 18 , wherein the wiring substrate is directly soldered to a lateral surface of the piezoelectric elements.
20 . The liquid ejecting apparatus according to claim 18 , wherein the melting point of the solder is greater than 90° C.