Flash evaporation-plasma coating deposition method

• US 20050003098A1
• Filed: 08/02/2004
• Published: 01/06/2005
• Est. Priority Date: 08/29/1997
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Kirk, Seth M., Esswein, William H., Kohler, Qunter A., Gates, Brian J.
• Granted Patent: US 7,189,436 B2
• Time in Patent Office: Days
• US Class Current: 427/488
• CPC Class Codes: B05D 1/62 Plasma-deposition of organic layers plasma deposition in general C23C14/00, C23C16/00
• CPC Class Codes: C23C 16/4485 by evaporation without using carrier gas in contact with the source material C23C16/4486 takes precedence
• CPC Class Codes: C23C 16/513 using plasma jets
• CPC Class Codes: Y10T 428/269 including synthetic resin or polymer layer or component
• CPC Class Codes: Y10T 428/273 of coating
• CPC Class Codes: Y10T 428/31663 As siloxane, silicone or silane

Abstract

The present invention provides a method for the formation of an organic coating on a substrate. The method includes: providing a substrate in a vacuum; providing at least one vaporized organic material comprising at least one component from at least one source, wherein the vaporized organic material is capable of condensing in a vacuum of less than about 130 Pa; providing a plasma from at least one source other than the source of the vaporized organic material; directing the vaporized organic material and the plasma toward the substrate; and causing the vaporized organic material to condense and polymerize on the substrate in the presence of the plasma to form an organic coating.

Claims

1. A method for the formation of an organic coating on a substrate comprising:

providing, in a vacuum, a chilled substrate, flash evaporator, and cathode and anode for generating a plasma;

vaporizing at least one organic liquid to form vaporized organic material capable of condensing in a vacuum of less than about 130 Pa;

generating the plasma;

directing the vaporized organic material and the plasma toward the substrate; and

condensing and polymerizing the vaporized organic material on the substrate in the presence of the plasma to form a polymeric coating.

2. The method of claim 1 wherein the condensing and polymerizing step comprises:

causing the plasma to interact with the vaporized organic material and form a reactive organic species; and

contacting the substrate with the reactive organic species to form the polymeric coating.

3. The method of claim 1 wherein the condensing and polymerizing step comprises:

condensing the vaporized organic material on the substrate in the presence of the plasma to form reactive species that polymerize to form the polymeric coating.

4. The method of claim 1 wherein the substrate is in close proximity to a radio frequency bias electrode such that the substrate is exposed to a radio frequency bias voltage.

5. The method of claim 1 wherein the coating has a density that is about 10% greater than the density of the organic liquid prior to vaporization.

6. The method of claim 1 wherein the coating has a density that is about 50% greater than the density of the organic liquid prior to vaporization.

7. The method of claim 1 wherein the vaporized organic material comprises vaporized mineral oil.

8. The method of claim 1 wherein the vaporized organic material comprises vaporized dimethylsiloxane oil.

9. The method of claim 1 comprising providing the chilled substrate, flash evaporator, cathode and anode in a vacuum chamber.

10. The method of claim 1 wherein the plasma generating step comprises:

injecting a plasma gas into a hollow cathode system;

providing a sufficient voltage to create and maintain a plasma within the hollow cathode system; and

maintaining a vacuum sufficient for maintaining the plasma.

11. The method of claim 1 comprising generating the plasma in a hollow cathode slot system comprising two electrode plates arranged parallel to each other.

12. The method of claim 1 comprising generating the plasma in a hollow cathode fed by a carrier gas and the vaporized organic material.

13. The method of claim 12 wherein vaporized organic material is formed from a high molecular weight organic liquid.

14. The method of claim 1 wherein the vaporized organic material is formed from a vaporized oil.

15. The method of claim 1 wherein the vaporized organic material is formed an oxygen-containing hydrocarbon.

16. The method of claim 1 wherein the vaporized organic material is formed from a saturated or unsaturated hydrocarbon, nitrogen-containing hydrocarbon, halogen-containing hydrocarbon, or silicon-containing hydrocarbon.

17. The method of claim 1 comprising generating the plasma in a hollow cathode tube.

18. The method of claim 1 wherein the cathode comprises:

a cylinder having an outlet end; and

a circular cross section orifice positioned inside the cylinder and recessed with respect to the outlet end.

19. The method of claim 1 wherein a divider keeps the plasma and vaporized organic material separate until they are close to the substrate.

20. The method of claim 1 wherein the plasma and vaporized organic material are not separated by a divider.

21. The method of claim 1 comprising maintaining the plasma using an inert gas.

22. The method of claim 1 comprising forming the coating as a single layer of polymerized material.

23. The method of claim 1 comprising forming the coating from a layer comprising multiple organic materials.

51. The method of claim 1 wherein the substrate comprises a flexible polymeric film.

52. The method of claim 51 wherein the film comprises oriented polyester, nylon or biaxially oriented polypropylene.

53. The method of claim 1 comprising forming a crosslinked coating.

54. The method of claim 1 comprising forming a multilayer coating

55. The method of claim 1 comprising forming a protective coating.

56. The method of claim 1 comprising forming a conductive coating.

57. The method of claim 1 comprising forming a resistive coating.

58. The method of claim 1 comprising forming a barrier coating.

59. The method of claim 58 comprising forming a barrier coating having water vapor barrier properties at least several orders of magnitude better than the uncoated substrate.

60. The method of claim 58 comprising forming a barrier coating having oxygen barrier properties at least several orders of magnitude better than the uncoated substrate.

61. The method of claim 1 wherein the flash evaporator uniformly discharges the vaporized organic material through an outlet port.

62. The method of claim 1 wherein the vaporized organic material is provided from at least one source and the plasma is provided from at least one source other than the source of the vaporized organic material.

63. The method of claim 1 wherein the vacuum is at a pressure less than about 1 torr (130 Pa).

64. The method of claim 1 wherein the vacuum is at a pressure less than about 8 millitorr (1 Pa).

65. The method of claim 1 wherein the substrate comprises a moving web having a speed of about 0.3 meter/minute to about 300 meters/minute.

66. The method of claim 1 wherein the substrate comprises a moving web having a speed of about 0.9 meter/minute to about 6 meters/minute.

24-50. -50. (Cancelled)