Conductive Films for EMI Shielding Applications

• US 20120012382A1
• Filed: 09/23/2011
• Published: 01/19/2012
• Est. Priority Date: 05/13/2009
• Status: Abandoned Application

• Current Assignee: Laird Technologies Incorporated (DuPont de Nemours, Inc.)
• Original Assignee: Laird Technologies Incorporated (DuPont de Nemours, Inc.)
• Inventors: McBain, Douglas, Hill, Richard F.
• Application Number:
  US13/243,685
• Publication Number:
  US 20120012382A1
• Time in Patent Office: Days
• US Class Current: 174/388
• CPC Class Codes: B32B 2038/0092 Metallizing
• CPC Class Codes: B32B 2309/105 Thickness
• CPC Class Codes: B32B 38/00 Ancillary operations in connection with laminating processes
• CPC Class Codes: H05K 9/0084 comprising a single continuous metallic layer on an electrically insulating supporting structure, e.g. metal foil, film, plating coating, electro-deposition, vapour-deposition
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor
• CPC Class Codes: Y10T 156/1028 by bending, drawing or stretch forming sheet to assume shape of configured lamina while in contact therewith

Abstract

According to various aspects, exemplary embodiments are provided of EMI shielding materials. In one exemplary embodiment, an EMI shielding material generally includes a conductive metal layer disposed on a thin carrier film. The EMI shielding material may be sufficiently compliant such that the conductive metal layer and thin carrier film are capable of conforming to an irregular surface when the EMI shielding material is applied to the irregular surface.

Claims

1. An EMI shielding material comprising:

a thin carrier film;

a conductive metal layer disposed on the thin carrier film,

wherein the thin carrier layer and conductive metal layer are configured to conform to an irregular surface of a mold cavity, such that the EMI shielding material may be insert molded onto a molded article; and

wherein the EMI shielding material imparts EMI shielding capability to a plastic article without requiring the plastic article to be made of a conductive plastic or painted with a conductive paint;

whereby the EMI shielding material is sufficiently compliant such that the conductive metal layer and thin carrier film are capable of conforming to an irregular surface when the EMI shielding material is applied to the irregular surface.

2. The EMI shielding material of claim 1, wherein the thin carrier film comprises at least one or more of polymer, teflon, polyester, acrylic, or plastic.

3. The EMI shielding material of claim 1, further comprising a protective liner disposed generally over the release coating on a side of the EMI shielding material opposite the thin carrier film.

4. The EMI shielding material of claim 1, wherein the conductive metal layer is disposed on the exterior of the plastic article and the thin carrier film is adhered to the plastic article.

5. The EMI shielding material of claim 1, wherein:

the thin carrier film has a thickness falling within a range of about 0.2 micrometers to about 5 micrometers; and

the conductive metal layer has a thickness falling within a range of about 5 Nanometers to about 100 nanometers.

6. An EMI shielding material comprising:

a thin carrier film;

a conductive metal layer disposed on the thin carrier film, the conductive metal layer having a thickness of less than or equal to 0.0005 inches; and

a release coating disposed on the EMI shielding material on a side opposite the thin carrier film, where the release coating is a low surface energy coating that allows for removal of the EMI shielding material from a surface in contact with the release coating;

whereby the conductive metal layer is sufficiently thin such that the EMI shielding material is capable of conforming to an irregular surface when the EMI shielding material is applied to the irregular surface.

7. The EMI shielding material of claim 6, further comprising at least one or more of a release coating, a release liner, and a protective liner disposed over the conductive metal layer.

8. The EMI shielding material of claim 6, further comprising a release liner disposed in a predetermined pattern along two or more portions of a side of the conductive metal layer opposite the thin carrier film.

9. The EMI shielding material of claim 6, further comprising a release liner disposed over the conductive metal layer and configured to allow for a relatively clean and easy release of the EMI shielding material from a surface in contact with the release liner.

10. The EMI shielding material of claim 9, wherein:

the thin carrier film has a thickness falling within a range of about 0.2 micrometers to about 5 micrometers;

the conductive metal layer has a thickness falling within a range of about 5 Nanometers to about 100 nanometers; and

the release liner has a thickness falling within a range of about 1 mil to about 10 mils.

11. The EMI shielding material of claim 6, wherein:

the thin carrier film has a thickness falling within a range of about 0.2 micrometers to about 5 micrometers; and

the conductive metal layer has a thickness falling within a range of about 5 Nanometers to about 100 nanometers.

12. The EMI shielding material of claim 6, wherein the thin carrier film comprises at least one or more of polymer, teflon, polyester, acrylic, or plastic.

13. The EMI shielding material of claim 6, further comprising a protective liner disposed generally over the release coating on a side of the EMI shielding material opposite the thin carrier film.

14. The EMI shielding material of claim 6, where the thin carrier film has a thickness of less than or equal to about 0.001 inches, whereby the thin carrier film is sufficiently thin such that the EMI shielding material is capable of conforming to an irregular surface when the EMI shielding material is applied to the irregular surface.

15. The EMI shielding material of claim 6, wherein:

the thin carrier film includes a first side;

the conductive metal layer is applied to the first side of the thin carrier film;

the conductive metal layer has a thickness of less than or equal to 0.0005 inches, and the thin carrier film has a thickness of less than or equal to about 0.001 inches;

whereby the conductive metal layer and the thin carrier film together have a combined thickness that is sufficiently thin to enable the EMI shielding material to conform to an irregular surface when the EMI shielding material is applied to the irregular surface.

16. A plastic article comprising the EMI shielding material of claim 15.

17. A plastic article comprising an EMI shielding material, the EMI comprising:

a thin carrier film; and

a conductive metal layer disposed on the thin carrier film, the conductive metal layer having a thickness of less than or equal to 0.0005 inches;

wherein the EMI shielding material imparts EMI shielding capability to the plastic article without requiring the plastic article to be made of a conductive plastic or painted with a conductive paint;

whereby the conductive metal layer is sufficiently thin such that the EMI shielding material is capable of conforming to an irregular surface when the EMI shielding material is applied to the irregular surface.

18. A method relating to the making of an EMI shielding material configured to conform to an irregular surface when the EMI shielding material is applied to irregular surface, the method comprising:

depositing conductive metal onto a carrier film having a thickness of less than or equal to about 0.001 inches, to thereby form a conductive metal layer having a thickness of less than or equal to 0.0005 inches; and

applying the EMI shielding material to a plastic article, whereby the EMI shielding material is operable for imparting EMI shielding capability to the plastic article.

19. The method of claim 18, wherein applying the EMI shielding material to a plastic article include applying the EMI shielding material to a surface within a mold cavity in which the plastic article is to be molded.

20. The method of claim 18, wherein the EMI shielding material imparts EMI shielding capability to the plastic article without having to make the plastic article out of a conductive plastic and without having to paint the plastic article with a conductive paint.

21. The method of claim 18, wherein:

the carrier film has a thickness falling within a range of about 0.2 micrometers to about 5 micrometers; and

the conductive metal layer has a thickness falling within a range of about 5 Nanometers to about 100 nanometers.

22. The method of claim 18, further comprising applying a release liner to the conductive metal layer.

23. The method of claim 22, wherein the release liner is applied such that the release liner has a thickness falling within a range of about 1 mil to about 10 mils.

24. The method of claim 22, further comprising applying a release coating to the release liner.

25. A method relating to the making of an EMI shielding material configured to conform to an irregular surface when the EMI shielding material is applied to irregular surface, the method comprising:

depositing conductive metal onto a carrier film having a thickness of less than or equal to about 0.001 inches, to thereby form a conductive metal layer having a thickness of less than or equal to 0.0005 inches; and

applying a release liner to the conductive metal layer, wherein applying the release liner includes;

laminating the conductive metal layer to an exposed surface of the release liner; and

drawing the conductive metal layer and the release liner between a pair of laminating rollers.

26. The method of claim 25, wherein the release liner is applied such that the release liner has a thickness falling within a range of about 1 mil to about 10 mils.

27. The method of claim 25, wherein:

the carrier film has a thickness falling within a range of about 0.2 micrometers to about 5 micrometers; and

the conductive metal layer has a thickness falling within a range of about 5 Nanometers to about 100 nanometers.

28. The method of claim 25, further comprising applying the EMI shielding material to a surface within a mold cavity.

29. The method of claim 25, further comprising applying a release coating to the release liner.