Conductive Polymer Dispersion with Enhanced Coverage

• US 20170098512A1
• Filed: 12/15/2016
• Published: 04/06/2017
• Est. Priority Date: 02/27/2012
• Status: Active Grant

• Current Assignee: Kemet Electronics Corporation (Yageo Corporation)
• Original Assignee: Kemet Electronics Corporation (Yageo Corporation)
• Inventors: Lessner, Phillip M., Chacko, Antony P., Ols, John Joseph, Shi, Yaru, Chen, Qingping
• Granted Patent: US 10,643,796 B2
• Time in Patent Office: Days
• CPC Class Codes: H01G 9/0036 Formation of the solid electrolyte layer
• CPC Class Codes: H01G 9/012 specially adapted for solid capacitors
• CPC Class Codes: H01G 9/028 Organic semiconducting electrolytes, e.g. TCNQ
• CPC Class Codes: H01G 9/0425 specially adapted for cathode
• CPC Class Codes: H01G 9/045 based on aluminium
• CPC Class Codes: H01G 9/08 Housing; Encapsulation
• CPC Class Codes: H01G 9/15 Solid electrolytic capacitors H01G11/00 takes precedence
• CPC Class Codes: Y10T 29/43 Electric condenser making

Abstract

An improved process for forming an electrolytic capacitor is provided. The process comprises: providing an anode with an anode wire extending from the anode body; forming a dielectric on the anode to form an anodized anode; applying a first slurry wherein the first slurry comprises conducting polymer and polyanion, wherein the polyanion and conducting polymer are in a first weight ratio thereby forming a first slurry layer; and applying a second slurry on the first slurry layer wherein the second slurry comprises the conducting polymer and said polyanion and wherein the polyanion and the conducting polymer are in a second weight ratio wherein the second weight ratio is lower than the first weight ratio.

Claims

1. A process for forming an electrolytic capacitor comprising:

providing an anode with an anode wire extending from said anode body;

forming a dielectric on said anode to form an anodized anode;

applying a first slurry wherein said first slurry comprises conducting polymer and polyanion, wherein said polyanion and conducting polymer are in a first weight ratio thereby forming a first slurry layer; and

applying a second slurry on said first slurry layer wherein said second slurry comprises said conducting polymer and said polyanion and wherein said polyanion and said conducting polymer are in a second weight ratio wherein said second weight ratio is lower than said first weight ratio.

2. The method for forming an electrolytic capacitor of claim 1 wherein said first weight ratio is no more than 6.

3. The method for forming an electrolytic capacitor of claim 1 wherein said first weight ratio is no more than 4.

4. The method for forming an electrolytic capacitor of claim 3 wherein said first weight ratio is no more than 3.4.

5. The method for forming an electrolytic capacitor of claim 4 wherein said first weight ratio is 3.0 to 3.4.

6. The method for forming an electrolytic capacitor of claim 1 wherein said second weight ratio is no more than 3.

7. The method for forming an electrolytic capacitor of claim 6 wherein said second weight ratio is no more than 2.

8. The method for forming an electrolytic capacitor of claim 7 wherein said second weight ratio is no more than 1.

9. The method for forming an electrolytic capacitor of claim 1 wherein said second weight ratio is less than said first weight ratio by at least 5%.

10. The method for forming an electrolytic capacitor of claim 9 wherein said second weight ratio is less than said first weight ratio by at least 6%.

11. The method for forming an electrolytic capacitor of claim 10 wherein said second weight ratio is less than said first weight ratio by at least 8%.

12. The method for forming an electrolytic capacitor of claim 1 further comprising forming a layer of conductive polymer on said dielectric prior to said applying said first slurry.

13. The method for forming an electrolytic capacitor of claim 12 wherein said forming said layer of conductive polymer comprises in-situ polymerization.

14. The method for forming an electrolytic capacitor of claim 1 wherein at least one of said first slurry or said second slurry comprises a crosslinker.

15. The method for forming an electrolytic capacitor of claim 14 wherein said polyanion and said crosslinker are in one molecule.

16. The method for forming an electrolytic capacitor of claim 14 wherein said crosslinker is an amine.

17. The method for forming an electrolytic capacitor of claim 16 wherein said amine is selected from a diamine and a monoamine.

18. The method for forming an electrolytic capacitor of claim 17 wherein said preferred diamine is diaminodecane.

19. The method for forming an electrolytic capacitor of claim 17 wherein said monoamine is tris(hydroxymethyl)aminomethane.

20. The method for forming an electrolytic capacitor of claim 1 wherein said conductive polymer comprises thiophene.

21. The method for forming an electrolytic capacitor of claim 20 wherein said thiophene comprises polyethylenedioxythiophene.

22. The method for forming an electrolytic capacitor of claim 1 wherein said polyanion comprises sulfonic acid.

23. The method for forming an electrolytic capacitor of claim 22 wherein said sulfonic acid is toluene sulfonic acid or polystyrene sulfonic acid.

24. The method for forming an electrolytic capacitor of claim 1 wherein said anode comprises a valve metal.

25. The method for forming an electrolytic capacitor of claim 24 wherein said valve metal comprises a material selected from the group consisting of Al, W, Ta, Nb, Ti, Zr and Hf.

26. A capacitor made by the method of claim 1.

27. A method of forming an electrolytic capacitor comprising:

providing an anode with an anode lead extending therefrom;

forming a dielectric on said anode;

forming a first dispersion layer from a first dispersion on said first conductive polymer layer wherein said first dispersion comprises a conducting polymer and a polyanion with a first weight ratio of polyanion to conducting polymer of no more than 6; and

forming a second dispersion layer on said first dispersion layer from a second dispersion wherein said second dispersion comprises said conducting polymer and said polyanion in a second weight ratio of said polyanion to said conducting polymer and said second weight ratio is lower than said first weight ratio and said second weight ratio is no more than 3.

28. The method for forming an electrolytic capacitor of claim 27 further comprising forming a first conductive polymer layer on said dielectric prior to said forming of said first dispersion layer.

29. The method for forming an electrolytic capacitor of claim 28 wherein said forming said first conductive polymer layer comprises in-situ polymerization.

30. The method for forming an electrolytic capacitor of claim 27 wherein at least one of said first slurry or said second slurry comprises a crosslinker.

31. The method for forming an electrolytic capacitor of claim 30 wherein said crosslinker is an amine.

32. The method for forming an electrolytic capacitor of claim 31 wherein said amine is selected from a diamine and a monoamine.

33. The method for forming an electrolytic capacitor of claim 32 wherein said diamine is diaminodecane.

34. The method for forming an electrolytic capacitor of claim 32 wherein said monamine is tris(hydroxymethyl)aminomethane.

35. The method for forming an electrolytic capacitor of claim 27 wherein said conductive polymer comprises thiophene.

36. The method for forming an electrolytic capacitor of claim 35 wherein said thiophene comprises polyethylenedioxythiophene.

37. The method for forming an electrolytic capacitor of claim 27 wherein said polyanion comprises sulfonic acid.

38. The method for forming an electrolytic capacitor of claim 37 wherein said sulfonic acid is toluene sulfonic acid or polystyrene sulfonic acid.

39. The method for forming an electrolytic capacitor of claim 27 wherein said first weight ratio is no more than 4.

40. The method for forming an electrolytic capacitor of claim 39 wherein said first weight ratio is no more than 3.4.

41. The method for forming an electrolytic capacitor of claim 40 wherein said first weight ratio is 3.0 to 3.4.

42. The method for forming an electrolytic capacitor of claim 27 said second weight ratio is no more than 2.

43. The method for forming an electrolytic capacitor of claim 42 said second weight ratio is no more than 1.

44. The method for forming an electrolytic capacitor of claim 27 wherein said second weight ratio is less than said first weight ratio by at least 5%.

45. The method for forming an electrolytic capacitor of claim 44 wherein said second weight ratio is less than said first weight ratio by at least 6%.

46. The method for forming an electrolytic capacitor of claim 45 wherein said second weight ratio is less than said first weight ratio by at least 8%.

47. The method for forming an electrolytic capacitor of claim 27 wherein said anode comprises a valve metal.

48. The method for forming an electrolytic capacitor of claim 47 wherein said valve metal comprises a material selected from the group consisting of Al, W, Ta, Nb, Ti, Zr and Hf.

49. A capacitor made by the method of claim 27.

50. A method of forming an electrolytic capacitor comprising:

providing an anode with an anode lead extending therefrom;

forming a dielectric on said anode;

forming a first conductive polymer layer on said dielectric;

forming a first dispersion layer from a first dispersion on said first conductive polymer layer wherein said first dispersion comprises a conducting polymer and a polyanion with a first weight ratio of polyanion to conducting polymer of no more than 6; and

forming a second dispersion layer on said first dispersion layer from a second dispersion wherein said second dispersion comprises said conducting polymer, said polyanion and a crosslinker and said second dispersion has a second weight ratio of said to polyanion to said conducting polymer and said second weight ratio is lower than said first weight ratio and said second weight ratio is no more than 3.

51. The method for forming an electrolytic capacitor of claim 50 wherein said forming of said first conductive polymer layer comprises in-situ polymerization.

52. The method for forming an electrolytic capacitor of claim 50 wherein said crosslinker is an amine.

53. The method for forming an electrolytic capacitor of claim 52 wherein said amine is a diamine or a monoamine.

54. The method for forming an electrolytic capacitor of claim 53 wherein said diamine is diaminodecane.

55. The method for forming an electrolytic capacitor of claim 53 wherein said monoamine is tris(hydroxymethyl)aminomethane.

56. The method for forming an electrolytic capacitor of claim 50 wherein said conductive polymer comprises thiophene.

57. The method for forming an electrolytic capacitor of claim 56 wherein said thiophene comprises polyethylenedioxythiophene.

58. The method for forming an electrolytic capacitor of claim 50 wherein said polyanion comprises sulfonic acid.

59. The method for forming an electrolytic capacitor of claim 58 wherein said sulfonic acid is toluene sulfonic acid or polystyrene sulfonic acid.

60. The method for forming an electrolytic capacitor of claim 50 wherein said first weight ratio is no more than 4.

61. The method for forming an electrolytic capacitor of claim 60 wherein said first weight ratio is no more than 3.4.

62. The method for forming an electrolytic capacitor of claim 61 wherein said first weight ratio is 3.0 to 3.4.

63. The method for forming an electrolytic capacitor of claim 50 wherein said second weight ratio is no more than 2.

64. The method for forming an electrolytic capacitor of claim 63 wherein said second weight ratio is no more than 1.

65. The method for forming an electrolytic capacitor of claim 50 wherein said second weight ratio is less than said first weight ratio by at least 5%.

66. The method for forming an electrolytic capacitor of claim 65 wherein said second weight ratio is less than said first weight ratio by at least 6%.

67. The method for forming an electrolytic capacitor of claim 66 wherein said second weight ratio is less than said first weight ratio by at least 8%.

68. The method for forming an electrolytic capacitor of claim 50 wherein said anode comprises a valve metal.

69. The method for forming an electrolytic capacitor of claim 68 wherein said valve metal comprises a material selected from the group consisting of Al, W, Ta, Nb, Ti, Zr and Hf.

70. A capacitor made by the method of claim 50.

71. A process for forming an electrolytic capacitor comprising:

providing an anode with an anode wire extending from said anode body;

forming a dielectric on said anode to form an anodized anode;

forming a layer of conductive polymer on said dielectric;

applying a first slurry on said layer of conductive polymer wherein said first slurry comprises conducting polymer and polyanion, wherein said polyanion and conducting polymer are in a first weight ratio thereby forming a first slurry layer; and

applying a second slurry on said first slurry layer wherein said second slurry comprises said conducting polymer and said polyanion and wherein said polyanion and said conducting polymer are in a second weight ratio.

72. The method for forming an electrolytic capacitor of claim 71 wherein said first weight ratio is no more than 6.

73. The method for forming an electrolytic capacitor of claim 72 wherein said first weight ratio is no more than 4.

74. The method for forming an electrolytic capacitor of claim 73 wherein said first weight ratio is no more than 3.4.

75. The method for forming an electrolytic capacitor of claim 74 wherein said first weight ratio is 3.0 to 3.4.

76. The method for forming an electrolytic capacitor of claim 71 wherein said second weight ratio is no more than 3.

77. The method for forming an electrolytic capacitor of claim 76 wherein said second weight ratio is no more than 2.

78. The method for forming an electrolytic capacitor of claim 77 wherein said second weight ratio is no more than 1.

79. The method for forming an electrolytic capacitor of claim 71 wherein said second weight ratio is less than said first weight ratio by at least 5%.

80. The method for forming an electrolytic capacitor of claim 79 wherein said second weight ratio is less than said first weight ratio by at least 6%.

81. The method for forming an electrolytic capacitor of claim 80 wherein said second weight ratio is less than said first weight ratio by at least 8%.

82. The method for forming an electrolytic capacitor of claim 71 wherein said forming of said layer of conductive polymer on said dielectric comprises in-situ polymerization.

83. The method for forming an electrolytic capacitor of claim 71 wherein at least one of said first slurry or said second slurry comprises a crosslinker.

84. The method for forming an electrolytic capacitor of claim 83 said polyanion and said crosslinker are in the same molecule.

85. The method for forming an electrolytic capacitor of claim 83 wherein said crosslinker is an amine.

86. The method for forming an electrolytic capacitor of claim 85 wherein said amine is selected from a diamine and a monoamine.

87. The method for forming an electrolytic capacitor of claim 86 wherein said diamine is diaminodecane.

88. The method for forming an electrolytic capacitor of claim 86 wherein said monoamine is tris(hydroxymethyl)aminomethane.

89. The method for forming an electrolytic capacitor of claim 71 wherein said conductive polymer comprises thiophene.

90. The method for forming an electrolytic capacitor of claim 89 wherein said thiophene comprises polyethylenedioxythiophene.

91. The method for forming an electrolytic capacitor of claim 71 wherein said polyanion comprises sulfonic acid.

92. The method for forming an electrolytic capacitor of claim 91 wherein said sulfonic acid is toluene sulfonic acid or polystyrene sulfonic acid.

93. The method for forming an electrolytic capacitor of claim 71 wherein said anode comprises a valve metal.

94. The method for forming an electrolytic capacitor of claim 93 wherein said valve metal comprises a material selected from the group consisting of Al, W, Ta, Nb, Ti, Zr and Hf.

95. A capacitor made by the method of claim 71.