Pressure-sensitive conductive ink composition

• US 6,555,024 B2
• Filed: 12/28/2000
• Issued: 04/29/2003
• Est. Priority Date: 12/28/1999
• Status: Expired due to Fees

• Current Assignee: Nitta Corporation
• Original Assignee: Nitta Corporation
• Inventors: Ueda, Tsutomu, Ooue, Toshikazu
• Primary Examiner(s): Kopec, Mark
• Assistant Examiner(s): VIJAYAKUMAR, KALLAMBELLA M
• Application Number:
  US09/753,230
• Publication Number:
  US 20010015423A1
• Time in Patent Office: 852 Days
• Field of Search: 252/511, 252/500, 524/492, 524/493, 524/495, 524/503, 428/325, 428/323, 737/63, 738/628
• US Class Current: 252/511
• CPC Class Codes: C09D 11/52 Electrically conductive inks
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles

Abstract

A pressure-sensitive conductive ink composition includes a thermoplastic resin and a conductive filler. The thermoplastic resin is added with a curing agent capable of a partial crosslinkable reaction. The resulting composition maintains its pressure-sensitive characteristics, even at elevated temperatures.

Claims

1. A pressure-sensitive conductive ink composition comprising:

a thermoplastic resin;

a conductive filler;

a non-conductive filler;

a curing agent partially crosslinking said thermoplastic resin;

said thermoplastic resin being a polyhydroxy ether; and

said non-conductive filler being ultrafine silicon dioxide having a primary particle diameter of about 7 nm.

2. The pressure-sensitive conductive ink composition according to claim 1, wherein said thermoplastic resin is a polyhydroxy ether having a structure according to the following formula (I):

wherein n is from 1 to about 500.

3. The pressure-sensitive conductive ink composition according to claim 1, wherein said thermoplastic resin is a polyhydroxy ether having a structure according to the following formula (II):

wherein n is from 1 to about 500.

4. The pressure-sensitive conductive ink composition according to claim 1, wherein said curing agent is at least one isocyanate selected from the group consisting of tolylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and xylylene diisocyanate.

5. The pressure-sensitive conductive ink composition according to claim 1, wherein said curing agent is at least one polyisocyanate selected from the group consisting of a burette type, an adduct type and an isocyanurate type of isocyanates of tolylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and xylylene diisocyanate.

6. The pressure-sensitive conductive ink composition according to claim 5, wherein:

said curing agent includes a blocking agent; and

said blocking agent includes at least one active hydrogen compound selected from the group consisting of methyl ethyl ketone, ε

-caprolactone, ethyl acetoacetate, and phenol.

7. The pressure-sensitive conductive ink composition according to claim 1, wherein:

said curing agent is an isocyanate curing agent; and

an NCO;

OH ratio of isocyanate in said curing agent to hydroxy in said polyhydroxy ether is in the range from about 0.2 to about 2.0.

8. The pressure-sensitive conductive ink composition according to claim 1, wherein said conductive filler is conductive carbon black having a developed structure with a DBP oil absorption from about 200 to about 480 ml/100 g.

9. The pressure-sensitive conductive ink composition according to claim 2, wherein said curing agent is at least one isocyanate selected from the group consisting of tolylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and xylylene diisocyanate.

10. The pressure-sensitive conductive ink composition according to claim 3, wherein said curing agent is at least one isocyanate selected from the group consisting of tolylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and xylylene diisocyanate.

11. The pressure-sensitive conductive ink composition according to claim 2, wherein said curing agent is at least one polyisocyanate selected from the group consisting of a burette type, an adduct type and an isocyanurate type of isocyanates of tolylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and xylylene diisocyanate.

12. The pressure-sensitive conductive ink composition according to claim 3, wherein said curing agent is at least one polyisocyanate selected from the group consisting of a burette type, an adduct type and an isocyanurate type of isocyanates of tolylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and xylylene diisocyanate.

13. The pressure-sensitive conductive ink composition according to claim 4, wherein:

said curing agent includes a blocking agent; and

said blocking agent includes at least one active hydrogen compound selected from the group consisting of methyl ethyl ketone, ε

-caprolactone, ethyl acetoacetate, and phenol.

14. The pressure-sensitive conductive ink composition according to claim 9, wherein:

said curing agent includes a blocking agent; and

said blocking agent includes at least one active hydrogen compound selected from the group consisting of methyl ethyl ketone, ε

-caprolactone, ethyl acetoacetate, and phenol.

15. The pressure-sensitive conductive ink composition according to claim 10, wherein:

said curing agent includes a blocking agent; and

said blocking agent includes at least one active hydrogen compound selected from the group consisting of methyl ethyl ketone, ε

-caprolactone, ethyl acetoacetate, and phenol.

16. The pressure-sensitive conductive ink composition according to claim 11, wherein:

said curing agent includes a blocking agent; and

said blocking agent includes at least one active hydrogen compound selected from the group consisting of methyl ethyl ketone, ε

-caprolactone, ethyl acetoacetate, and phenol.

17. The pressure-sensitive conductive ink composition according to claim 12, wherein:

said curing agent includes a blocking agent; and

said blocking agent includes at least one active hydrogen compound selected from the group consisting of methyl ethyl ketone, ε

-caprolactone, ethyl acetoacetate, and phenol.

18. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 1.

19. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition to claim 12.

20. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 3.

21. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 4.

22. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 5.

23. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 6.

24. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 7.

25. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 8.

26. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 9.

27. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 10.

28. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 11.

29. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 12.

30. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 13.

31. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 14.

32. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 15.

33. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 16.

34. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 17.

35. A pressure-sensitive conductive ink composition comprising:

a thermoplastic resin;

a conductive filler; and

a curing agent partially crosslinking said thermoplastic resin, wherein the thermoplastic resin is a polyhydroxy ether having a structure according to the following formula (II);

wherein n is from 1 to about 500.

36. A pressure-sensitive sensor comprising said pressure-sensitive conductive ink composition according to claim 35.