HYBRID SHEET MATERIALS AND METHODS OF PRODUCING SAME

• US 20140146477A1
• Filed: 11/28/2012
• Published: 05/29/2014
• Est. Priority Date: 11/28/2012
• Status: Abandoned Application

• Current Assignee: Illinois Tool Works Inc.
• Original Assignee: Illinois Tool Works Inc.
• Inventors: Youn, Seung Hoon
• Application Number:
  US13/687,655
• Publication Number:
  US 20140146477A1
• Time in Patent Office: Days
• US Class Current: 361/705
• CPC Class Codes: B32B 15/18 comprising iron or steel B32B15/011, B32B15/012 and B32B15/013 take precedence
• CPC Class Codes: B32B 15/20 comprising aluminium or copper B32B15/016 and B32B15/017 take precedence
• CPC Class Codes: B32B 2037/243 Coating
• CPC Class Codes: B32B 2307/212 Electromagnetic interference shielding
• CPC Class Codes: B32B 2307/302 Conductive
• CPC Class Codes: B32B 2307/54 Yield strength; Tensile strength
• CPC Class Codes: B32B 2309/105 Thickness
• CPC Class Codes: B32B 2309/12 Pressure
• CPC Class Codes: B32B 2311/00 Metals, their alloys or their compounds
• CPC Class Codes: B32B 2313/04 Carbon
• CPC Class Codes: B32B 2457/00 Electrical equipment
• CPC Class Codes: B32B 37/10 characterised by the pressing technique, e.g. using action of vacuum or fluid pressure
• CPC Class Codes: B32B 37/12 characterised by using adhesives
• CPC Class Codes: B32B 37/1284 Application of adhesive
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: B32B 9/007 comprising carbon, e.g. graphite, composite carbon
• CPC Class Codes: B32B 9/041 of metal
• CPC Class Codes: H05K 7/20472 Sheet interfaces
• CPC Class Codes: H05K 7/20481 characterised by the material composition exhibiting specific thermal properties
• 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: H05K 9/0088 : comprising a plurality of shielding layers; combining different shielding material structure
• CPC Class Codes: Y10T 156/10 : Methods of surface bonding and/or assembly therefor

Abstract

A hybrid sheet material includes an EMI absorption layer bonded to a thermal absorption layer. The EMI absorption layer may include a homogeneous mixture of a binder, silicon, and at least one metal. The thermal absorption layer may include a homogeneous mixture of a graphite material and a binder. According to a further aspect, a mobile device that includes a hybrid sheet material is provided. Other aspects include methods for producing the hybrid sheet material.

Claims

1. A hybrid sheet material comprising:

an electromagnetic interference (EMI) absorption layer comprising a first binder and at least one metal; and

a thermal absorption layer bonded to at least one surface of the EMI absorption layer, the thermal absorption layer comprising a mixture of a graphite material and a second binder.

2. The hybrid sheet material of claim 1, wherein the metal of the EMI absorption layer comprises at least one of iron, aluminum, and chromium.

3. The hybrid sheet material of claim 1, wherein the EMI absorption layer has a thickness of from about 50 microns to about 500 microns.

4. The hybrid sheet material of claim 3, wherein the thermal absorption layer has a thickness of from about 10 to about 200 microns.

5. The hybrid sheet material of claim 1, wherein the EMI absorption layer comprises:

between about 10 and 20 percent by weight of the first binder;

between about 15 and 25 percent by weight of the silicon;

between about 5 and 10 percent by weight of aluminum; and

between about 45 and 55 percent by weight of iron.

6. The hybrid sheet material of claim 1, wherein the EMI absorption layer comprises:

between about 5 and 15 percent by weight of the first binder;

between about 1 and 10 percent by weight of the silicon;

between about 1 and 10 percent by weight of chromium; and

between about 70 and 90 percent by weight of iron.

7. The hybrid sheet material of claim 1, wherein the EMI absorption layer is characterized by a capacity to absorb at least a portion of electromagnetic waves having a frequency from about 1 MHz to about 6 GHz.

8. The hybrid sheet material of claim 1, further comprising an adhesive layer formed on at least one surface of the EMI absorption layer or the thermal absorption layer.

9. A method for producing a hybrid sheet material comprising:

providing an electromagnetic interference (EMI) absorption powder mixture comprising a first binder, silicon, and at least one metal;

providing a thermal absorption sheet material having a first surface and a second surface and comprising a homogeneous mixture of a graphite material and a second binder; and

coating the first surface of the thermal absorption sheet material with the EMI absorption powder mixture to form a hybrid structure.

10. The method of claim 9, further comprising bonding the hybrid structure at a temperature from about 80°

C. to about 200°

C. for a period of time ranging from about 30 minutes to about 2 hours.

11. The method of claim 10, further comprising bonding the hybrid structure at a pressure from about 1400 psi to about 2100 psi.

12. The method of claim 11, further comprising laminating the hybrid sheet material with a pressure sensitive adhesive.

13. The method of claim 9, wherein coating the first surface of the thermal absorption sheet material comprises arranging the EMI absorption powder mixture in a unidirectional pattern onto the thermal absorption sheet material.

14. The method of claim 9, wherein the metal comprises at least one of iron, aluminum, and chromium.

15. An electronic device, comprising:

a heat producing electronic component; and

a hybrid sheet material proximate the heat producing electronic component and comprising;

an electromagnetic interference (EMI) absorption layer comprising a first binder material, silicon, and at least one metal; and

a thermal absorption layer bonded to at least one surface of the EMI absorption layer, the thermal absorption layer comprising a graphite material and a second binder.

16. The electronic device of claim 15, wherein the heat producing electronic component is a display panel.

17. The electronic device of claim 15, further comprising a near field communication (NFC) antenna and wherein the heat producing electronic component is a battery positioned adjacent the NFC antenna.

18. The electronic device of claim 17, further comprising an adhesive material positioned between the battery and the NFC antenna and between the EMI absorption layer of the hybrid sheet material and the NFC antenna.

19. The electronic device of claim 15, wherein the metal of the EMI absorption layer comprises at least one of iron, aluminum, and chromium.

20. The electronic device of claim 15, wherein the electronic device is a mobile device.