High frequency electromagnetic radiation absorbent coating comprising a binder and chips obtained from a laminate of alternating amorphous magnetic films and electrically insulating

• US 5,169,713 A
• Filed: 02/13/1991
• Issued: 12/08/1992
• Est. Priority Date: 02/22/1990
• Status: Expired due to Fees

• Current Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Original Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Inventors: Kumurdjian, Pierre
• Primary Examiner(s): Thibodeau, Paul J.
• Assistant Examiner(s): Resan, Stevan A.
• Application Number:
  US07/654,664
• Time in Patent Office: 664 Days
• Field of Search: 428/692, 428/323, 428/327, 428/328, 428/403, 428/402, 342/1, 342/2, 342/3, 342/4, 427/128
• US Class Current: 428/323
• CPC Class Codes: C09D 5/32 Radiation-absorbing paints protection against X-, gamma- or corpuscular radiation G21F
• CPC Class Codes: H05K 9/0083 comprising electro-conductive non-fibrous particles embedded in an electrically insulating supporting structure, e.g. powder, flakes, whiskers H05K9/0086 takes precedence
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/254 Polymeric or resinous material
• CPC Class Codes: Y10T 428/256 Heavy metal or aluminum or compound thereof
• CPC Class Codes: Y10T 428/2982 Particulate matter [e.g., sphere, flake, etc.]

Abstract

Radiation absorbent coating and process for its production.

The radiation absorbent coating comprises a binder and chips able to absorb ultrahigh frequency electromagnetic radiation. The chips comprise a series of layers alternately constituted by electrically insulating layers (16, 20) and layers (14, 18) made from a stack of films of alternating amorphous magnetic films (50) and electrically insulating films (60) each from 2-5 nanometers thick.

Claims

1. Absorbent coating comprising a binder and a charge constituted by chips able to absorb electromagnetic radiation, wherein each of said chips comprises a stack of films alternately constituted by an amorphous magnetic film and an insulating film of electrically insulating material, each of said magnetic and insulating films having a thickness of from about 2 to 5 nanometers and wherein the resistivity of the stack of films exceeds approximately 5 ohm-cm.

3. Absorbent coating according to claim 1 or 2, wherein the thickness of each of said amorphous magnetic films is approximately 3 nm.

4. Absorbent coating according to claim 1 or 2, wherein the thickness of each of said insulating films is approximately 5 nm.

5. Absorbent coating according to claim 1 or 2, wherein said insulating films are made of carbon.

6. Absorbent coating according to claim 1 or 2, wherein said insulating films are made of an organic material.

7. Absorbent layer comprising at least one layer of a coating according to claim 1 or 2.

8. Absorbent layer comprising at least one layer of a coating according to claim 1 or 2 and wherein said insulating films are selected from the group consisting of carbon and an organic material.

2. Absorbent coating comprising a binder and a charge constituted by chips able to absorb electromagnetic radiation, wherein each of said chips comprise a series of layers alternately constituted by an electrically insulating layer and a layer made of a stack of films, said stack of films alternately constituted by an amorphous magnetic film and an insulating film of electrically insulating material, each of said magnetic and insulating films having a thickness of from about 2 to 5 nanometers and wherein the resistivity of the stack of films exceeds approximately 5 ohm-cm.

9. A process for the production of an absorbent coating able to absorb electromagnetic radiation comprising the steps of:

depositing on a substrate a stack of films alternately constituted by an amorphous magnetic film and an insulating film of electrically insulating material, each of said magnetic and insulating films having a thickness of from about 2 to 5 nanometers, and wherein the resistivity of the stack of films exceeds approximately 5 ohm-cm,

breaking up said stack to reduce it into chips, and mixing said chips with a binder.

10. A process for the production of an absorbent coating for absorbing electromagnetic radiation comprising the steps of:

depositing on a substrate a series of layers alternately constituted by an electrically insulating layer and a layer made of a stack of films, said stack of films alternately constituted by an amorphous magnetic film and an insulating film of electrically insulating material, said magnetic and insulating films having a thickness of from about 2 to 5 nanometers, wherein the resistivity of the stack of films exceeds approximately 5 ohm-cm and breaking up said stack to reduce it into chips, and mixing said chips with a binder.