Piezoelectric element

Patent metadata

Field	Value
Publication number	US-9450174-B2
Application number	US-201414458632-A
Country	US
Kind code	B2
Filing date	Aug 13, 2014
Priority date	Feb 14, 2012
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

Poly(α-amino acid) which contain: (A) a glutamic acid γ-ester unit represented by formula (I): and (B) one or more kinds of units selected from a glutamic acid γ-ester unit represented by formula (II), an alanine unit, a phenylalanine unit and an N ε -benzyloxycarbonyllysine unit, represented by formula (III), and a glutamic acid γ-ester unit represented by formula (IV) can be dissolved in various solvents and are useful for preparing piezoelectric elements which exhibit superior piezoelectricity.

First claim

The invention claimed is:

1. A piezoelectric element, comprising at least one poly(α-amino acid), which contains:
(A) glutamic acid γ-ester units represented by formula (I):

wherein R 1 is a methyl group or a benzyl group; and
(B) units of one or more types selected from the group consisting of:
(1) a glutamic acid γ-ester unit represented by formula (II):

wherein R 2 is an unsubstituted alkyl group having 6 to 18 carbon atoms, or a substituted alkyl group having 1 to 6 carbon atoms, in which the hydrogen atoms are partly or entirely substituted by a halogen atom or an alicyclic hydrocarbon group having 3 to 12 carbon atoms;
(2) an alanine unit, a phenylalanine unit, and an N ε -benzyloxycarbonyllysine unit, which are represented by formula (III):

wherein R 3 is a methyl group, a benzyl group or a (CH 2 ) 4 —NHZ group, in which Z is a benzyloxycarbonyl group; and
(3) a glutamic acid γ-ester unit represented by formula (IV):

wherein each R 4 may be the same or different and is an alkoxy group having 1 to 12 carbon atoms; an alkyl group having 1 to 12 carbon atoms, in which the hydrogen atoms are partly or entirely substituted by a halogen atom; or an alkylcarbonyl group, in which the alkyl group has 1 to 12 carbon atoms; l is an integer of 6 to 12; and m is an integer of 1 to 3.

2. The piezoelectric element according to claim 1 , wherein R 2 is an unsubstituted alkyl group having 6 to 18 carbon atoms, or an alkyl group having 1 to 6 carbon atoms in which the hydrogen atoms are partly or entirely substituted by a fluorine atom or norbornyl group.

3. The piezoelectric element according to claim 1 , wherein R 2 is an n-hexyl group, an n-dodecyl group, an n-hexadecyl group, a 2-norbornylmethyl group, or a 2,2,2-trifluoroethyl group.

4. The piezoelectric element according to claim 1 , wherein R 3 is a (CH 2 ) 4 —NHZ group, in which Z is a benzyloxycarbonyl group.

5. The piezoelectric element according to claim 1 , wherein R 4 is an alkoxy group having 1 to 6 carbon atoms; an alkyl group having 1 to 12 carbon atoms, in which the hydrogen atoms are partly or entirely substituted by a fluorine atom; or an alkylcarbonyl group, in which the alkyl group has 3 to 9 carbon atoms.

6. The piezoelectric element according to claim 1 , wherein R 4 is a methoxy group, a butoxy group, a hexyloxy group, a trifluoromethyl group, or an n-hexylcarbonyl group.

7. The piezoelectric element according to claim 1 , wherein the polyamino acid is one or more kinds selected from the group consisting of:
a γ-methyl-L-glutamic acid/γ-hexyl-L-glutamic acid copolymer,
a γ-methyl-L-glutamic acid/γ-dodecyl-L-glutamic acid copolymer,
a γ-benzyl-L-glutamic acid/γ-dodecyl-L-glutamic acid copolymer,
a γ-methyl-L-glutamic acid/γ-hexadecyl-L-glutamic acid copolymer,
a γ-methyl-L-glutamic acid/γ-2,2,2-trifluoroethyl-L-glutamic acid copolymer,
a γ-methyl-L-glutamic acid/γ-2-norbornylmethyl-L-glutamic acid copolymer,
a γ-benzyl-L-glutamic acid/γ-2-norbornylmethyl-L-glutamic acid copolymer,
a γ-methyl-L-glutamic acid/γ-(6-(p-methoxyphenoxy)-1-hexyl)-L-glutamic acid copolymer,
a γ-methyl-L-glutamic acid/γ-(6-(p-hexylcarbonylphenoxy)-1-hexyl)-L-glutamic acid copolymer,
a γ-methyl-L-glutamic acid/γ-(10-(p-methoxyphenoxy)-1-decyl)-L-glutamic acid copolymer,
a γ-methyl-L-glutamic acid/γ-(6-(p-butoxyphenoxy)-1-hexyl)-L-glutamic acid copolymer,
a γ-methyl-L-glutamic acid/γ-(6-(p-hexyloxyphenoxy)-1-hexyl)-L-glutamic acid copolymer,
a γ-methyl-L-glutamic acid/γ-(6-(3,5-bis(trifluoromethyl)phenoxy)-1-hexyl)-L-glutamic acid copolymer,
a γ-methyl-L-glutamic acid/N ε -benzyloxycarbonyl-L-lysine copolymer,
a γ-benzyl-L-glutamic acid/N ε -benzyloxycarbonyl-L-lysine copolymer,
a γ-methyl-L-glutamic acid/L-phenylalanine copolymer, a γ-benzyl-L-glutamic acid/L-phenylalanine copolymer, and
a γ-benzyl-L-glutamic acid/L-alanine copolymer.

8. The piezoelectric element according to claim 1 , wherein the poly(α-amino acid) is a random copolymer.

9. The piezoelectric element according to claim 1 , wherein the poly(α-amino acid) is a block copolymer.

10. The piezoelectric element according to claim 1 , wherein the poly(α-amino acid) has a weight average molecular weight (Mw) of 1,000 to 5,000,000.

11. The piezoelectric element according to claim 1 , further comprising a flexible substrate and an electrode.

12. The piezoelectric element according to claim 1 , wherein the poly(α-amino acid) is in the form of a thin film.

13. The piezoelectric element according to claim 12 , wherein the poly(α-amino acid) is in the form of a thin film having a thickness of 500 nm to 500 μm.

14. A method of producing a piezoelectric element according to claim 1 , comprising:
(a) forming a lower electrode on a first flexible support;
(b) forming a film of a poly(α-amino acid) on said lower electrode; and
(c) forming an upper electrode on said film of a poly(α-amino acid).

15. A polyamino acid-containing ink, comprising:
(1) at least one poly(α-amino acid), which contains:
(A) glutamic acid γ-ester units represented by formula (I):

wherein R 1 is a methyl group or a benzyl group; and
(B) units of one or more types selected from the group consisting of:
(1) a glutamic acid γ-ester unit represented by formula (II):

wherein R 2 is an unsubstituted alkyl group having 6 to 18 carbon atoms, or a substituted alkyl group having 1 to 6 carbon atoms, in which the hydrogen atoms are partly or entirely substituted by a halogen atom or an alicyclic hydrocarbon group having 3 to 12 carbon atoms;
(2) an alanine unit, a phenylalanine unit, and an N ε -benzyloxycarbonyllysine unit, which are represented by formula (III):

wherein R 3 is a methyl group, a benzyl group or a (CH 2 ) 4 —NHZ group, in which Z is a benzyloxycarbonyl group; and
(3) a glutamic acid γ-ester unit represented by formula (IV):

wherein each R 4 may be the same or different and is an alkoxy group having 1 to 12 carbon atoms; an alkyl group having 1 to 12 carbon atoms, in which the hydrogen atoms are partly or entirely substituted by a halogen atom; or an alkylcarbonyl group, in which the alkyl group has 1 to 12 carbon atoms; l is an integer of 6 to 12; and m is an integer of 1 to 3; and

(2) at least one solvent.

Assignees

• Ajinomoto Kk

Inventors

• Ohashi Satoru
• Uemura Sei
• Kitazawa Manabu
• Kamata Toshihide
• Wada Yoshinori

Classifications

• Y10T29/42

  Piezoelectric device making · CPC title

• H01L41/29

  Electricity · mapped topic

• H01L41/193 Primary

  Electricity · mapped topic

• H01L41/45

  Electricity · mapped topic

• C08G69/10 Primary

  Alpha-amino-carboxylic acids {(polysuccinimides C08G73/1092)} · CPC title