Method of manufacturing thin film, substrate having thin film, electron emission material, method of manufacturing electron emission material, and electron emission device

• US 7,927,169 B2
• Filed: 11/21/2005
• Issued: 04/19/2011
• Est. Priority Date: 11/22/2004
• Status: Expired due to Fees

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Nissin Kogyo Company Limited (Hitachi, Ltd.)
• Inventors: Noguchi, Toru, Magario, Akira
• Primary Examiner(s): Patel; Nimeshkumar D
• Assistant Examiner(s): Raabe; Christopher M
• Application Number:
  US11/282,614
• Publication Number:
  US 20060214560A1
• Time in Patent Office: 1,975 Days
• Field of Search: 445/51, 313495-497, 428/367
• US Class Current: 445/51
• CPC Class Codes: B29C 43/24 Calendering
• CPC Class Codes: B29K 2105/162 Nanoparticles
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C08J 2321/00 Characterised by the use of unspecified rubbers
• CPC Class Codes: C08J 5/005 Reinforced macromolecular compounds with nanosized materials, e.g. nanoparticles, nanofibres, nanotubes, nanowires, nanorods or nanolayered materials
• CPC Class Codes: C08K 2201/011 Nanostructured additives
• CPC Class Codes: C08K 3/041 Carbon nanotubes
• CPC Class Codes: C08L 9/06 Copolymers with styrene
• CPC Class Codes: C09D 107/00 Coating compositions based on natural rubber
• CPC Class Codes: C09D 109/06 Copolymers with styrene
• CPC Class Codes: C09D 123/16 Elastomeric ethene-propene or ethene-propene-diene copolymers, e.g. EPR and EPDM rubbers
• CPC Class Codes: C09D 7/62 modified by treatment with other compounds
• CPC Class Codes: C09D 7/67 Particle size smaller than 100 nm
• CPC Class Codes: C09D 7/68 Particle size between 100-1000 nm
• CPC Class Codes: C09D 7/70 characterised by shape, e.g. fibres, flakes or microspheres
• CPC Class Codes: H01J 1/304 Field-emissive cathodes
• CPC Class Codes: H01J 2201/30469 Carbon nanotubes (CNTs)
• CPC Class Codes: H01J 31/123 Flat display tubes
• CPC Class Codes: H01J 61/0675 characterised by the material of the electrode
• CPC Class Codes: H01J 61/0735 : characterised by the material of the electrode
• CPC Class Codes: H01J 63/02 : Details, e.g. electrode, gas filling, shape of vessel
• CPC Class Codes: H01J 9/025 : of field emission cathodes
• CPC Class Codes: Y10T 428/249939 : Two or more layers
• CPC Class Codes: Y10T 428/2918 : including free carbon or carbide or therewith [not as steel]

Abstract

A method of manufacturing a thin film, including: mixing carbon nanofibers into an elastomer including an unsaturated bond or a group having affinity to the carbon nanofibers, and dispersing the carbon nanofibers by applying a shear force to obtain a carbon fiber composite material; mixing the carbon fiber composite material and a solvent to obtain a coating liquid; and applying the coating liquid to a substrate to form a thin film.

Claims

1. A method of manufacturing a thin film, the method comprising:

mixing carbon nanofibers into an elastomer including an unsaturated bond or a group having affinity to the carbon nanofibers, and dispersing the carbon nanofibers by applying a shear force to obtain a carbon fiber composite material;

mixing the carbon fiber composite material and a solvent to obtain a coating liquid; and

applying the coating liquid to a substrate to form a thin film;

wherein a network component of the elastomer in an uncrosslinked form has a spin-spin relaxation time (T2n) measured at 30°

C. by a Hahn-echo method using a pulsed nuclear magnetic resonance (NMR) technique with ¹H as an observing nucleus of 100 to 3,000 μ

sec, and

wherein obtaining the carbon fiber composite material is performed at 0 to 50°

C.

2. The method of manufacturing a thin film as defined in claim 1, wherein the elastomer has a molecular weight of 5,000 to 5,000,000.

3. The method of manufacturing a thin film as defined in claim 1, wherein at least one of a main chain, a side chain, and a terminal chain of the elastomer includes at least one of a double bond, a triple bond, a-hydrogen, a carbonyl group, a carboxyl group, a hydroxyl group, an amino group, a nitrile group, a ketone group, an amide group, an epoxy group, an ester group, a vinyl group, a halogen group, a urethane group, a biuret group, an allophanate group, and a urea group.

4. The method of manufacturing a thin film as defined in claim 1, wherein a network component of the elastomer in an crosslinked form has a spin-spin relaxation time (T2n) measured at 30°

C. by a Hahn-echo method using a pulsed nuclear magnetic resonance (NMR) technique of 100 to 2,000 μ

sec.

5. The method of manufacturing a thin film as defined in claim 1, wherein the carbon nanofibers have an average diameter of 0.5 to 500 nm.

6. The method of manufacturing a thin film as defined in claim 1, wherein the step of obtaining the carbon fiber composite material includes tight milling a mixture of the carbon nanofibers and the elastomer by using an open-roll method with a roll interval of 0.5 mm or less.

7. The method of manufacturing a thin film as defined in claim 6, wherein two rolls used in the open-roll method have a surface velocity ratio of 1.05 to 3.00.

8. The method of manufacturing a thin film as defined in claim 1, wherein the step of obtaining the carbon fiber composite material is performed by an internal mixing method.

9. The method of manufacturing a thin film as defined in claim 1, wherein the step of obtaining the carbon fiber composite material is performed by a multi-screw extrusion kneading method.

10. The method of manufacturing a thin film as defined in claim 1, wherein the step of forming the thin film is performed by a method selected from the group consisting of a spin coating method, a dipping method, a screen printing method, a spraying method, and an inkjet method.

11. A method of manufacturing an electron emission material, the method comprising:

mixing carbon nanofibers into an elastomer including an unsaturated bond or a group having affinity to the carbon nanofibers, and

dispersing the carbon nanofibers by applying a shear force to obtain a carbon fiber composite material,

wherein a network component of the elastomer in an uncrosslinked form has a spin-spin relaxation time (T2n) measured at 30°

C. by a Hahn-echo method using a pulsed nuclear magnetic resonance (NMR) technique with ¹H as an observing nucleus of 100 to 3,000 μ

sec, and

wherein obtaining the carbon fiber composite material is performed at 0 to 50°

C.

12. The method of manufacturing an electron emission material as defined in claim 11, wherein the elastomer has a molecular weight of 5,000 to 5,000,000.

13. The method of manufacturing an electron emission material as defined in claim 11, wherein at least one of a main chain, a side chain, and a terminal chain of the elastomer includes at least one of a double bond, a triple bond, a-hydrogen, a carbonyl group, a carboxyl group, a hydroxyl group, an amino group, a nitrile group, a ketone group, an amide group, an epoxy group, an ester group, a vinyl group, a halogen group, a urethane group, a biuret group, an allophanate group, and a urea group.

14. The method of manufacturing an electron emission material as defined in claim 11, wherein a network component of the elastomer in an crosslinked form has a spin-spin relaxation time (T2n) measured at 30°

C. by a Hahn-echo method using a pulsed nuclear magnetic resonance (NMR) technique of 100 to 2,000 μ

sec.

15. The method of manufacturing an electron emission material as defined in claim 11, wherein the carbon nanofibers have an average diameter of 0.5 to 500 nm.

16. The method of manufacturing an electron emission material as defined in claim 11, wherein the step of obtaining the carbon fiber composite material includes tight milling a mixture of the carbon nanofibers and the elastomer by using an open-roll method with a roll interval of 0.5 mm or less.

17. The method of manufacturing an electron emission material as defined in claim 16, wherein two rolls used in the open-roll method have a surface velocity ratio of 1.05 to 3.00.

18. The method of manufacturing an electron emission material as defined in claim 11, wherein the step of obtaining the carbon fiber composite material is performed by an internal mixing method.

19. The method of manufacturing an electron emission material as defined in claim 11, wherein the step of obtaining the carbon fiber composite material is performed by a multi-screw extrusion kneading method.