Piezoelectric laminate films and processes for their manufacture

• US 5,356,500 A
• Filed: 03/20/1992
• Issued: 10/18/1994
• Est. Priority Date: 03/20/1992
• Status: Expired due to Term

• Current Assignee: Rutgers University
• Original Assignee: Rutgers University
• Inventors: Su, Ji, Newman, Brian A., Scheinbeim, Jerry I.
• Primary Examiner(s): Simmons, David A.
• Assistant Examiner(s): Mayes, M. Curtis
• Application Number:
  US07/854,110
• Time in Patent Office: 942 Days
• Field of Search: 156/229, 156/299, 156/300, 156/309.6, 156/311, 29/25.35, 252/62.9 R, 310/311, 310/357
• US Class Current: 156/229
• CPC Class Codes: B29C 55/023 using multilayered plates or sheets
• CPC Class Codes: B32B 38/00 Ancillary operations in connection with laminating processes
• CPC Class Codes: B32B 38/0012 Mechanical treatment, e.g. roughening, deforming, stretching
• CPC Class Codes: B32B 38/0036 Heat treatment for heating or cooling of layers during lamination B32B37/06, B32B37/08
• CPC Class Codes: H10N 30/098 Forming organic materials
• CPC Class Codes: Y10T 29/42 Piezoelectric device making

Abstract

Provided by this invention are piezoelectric laminate films wherein films of different polymers are in laminated relationship. The piezoelectric laminate film has at least one property which is superior to the corresponding property in the films used in the lamination to form the laminate. Also provided is a method for making the laminate.

Claims

1. A method for providing a piezoelectric laminate film comprising the following steps:

a) melting at least two polymeric films formed of different polymers and quenching them;

b) place one surface of one quenched film upon one surface of another quenched film in intimate contact therewith;

c) laminate said quenched films whose surfaces are in intimate contact by co-melt pressing;

d) repeat steps b) and c) until all polymeric films are laminated;

e) quench said laminate;

f) cold draw said quenched laminate, and

g) pole said drawn laminate to form said piezoelectric laminate film having one or more properties superior to the corresponding property of the individual polymeric films used to make said piezoelectric laminate film.

2. A method of claim 1 wherein the formed piezoelectric laminate film is annealed.

3. A method of cLaim 1 wherein at least one polymeric film is poly(vinylidene fluoride) film.

4. A method of claim 1 wherein at least one polymeric film is an odd Nylon film.

5. A method of claim 1 wherein the provided piezoelectric laminate film has a poly(vinylidene fluoride) film and Nylon 7 or Nylon 11 film in laminated relationship.