ARTICLES AND METHODS INCLUDING PATTERNED SUBSTRATES FORMED FROM DENSIFIED, ADHERED METAL POWDERS

• US 20090320998A1
• Filed: 05/02/2008
• Published: 12/31/2009
• Est. Priority Date: 03/20/2006
• Status: Abandoned Application

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Do, Thanh-Huong T., Hackett, Steven C., Michel, Matthew J., Brown, Katherine A., Nees, Terry S.
• Application Number:
  US12/114,158
• Publication Number:
  US 20090320998A1
• Time in Patent Office: Days
• US Class Current: 156/219
• CPC Class Codes: H05K 1/0393 Flexible materials H05K1/038 takes precedence; specific organic compositions are classified in H05K1/0313 and subgroups
• CPC Class Codes: H05K 2203/0108 Male die used for patterning, punching or transferring
• CPC Class Codes: H05K 2203/0143 Using a roller; Specific shape thereof; Providing locally adhesive portions thereon
• CPC Class Codes: H05K 3/102 by bonding of conductive powder, i.e. metallic powder H05K3/12 takes precedence
• CPC Class Codes: H05K 3/281 by means of a preformed insulating foil H05K3/284 takes precedence
• CPC Class Codes: H05K 3/386 by the use of an organic polymeric bonding layer, e.g. adhesive
• CPC Class Codes: Y10T 156/1039 Surface deformation only of sandwich or lamina [e.g., embossed panels]
• CPC Class Codes: Y10T 428/24917 including metal layer

Abstract

In general the disclosure relates to manufacturing methods for producing conductive patterns on flexible substrates. For example, a layer of a metal powder composition is deposited onto an adhesive overlaying a substrate. Pressure is applied to the metal powder composition on the adhesive coated substrate web by a die having one or more projections, in order to reproduce a pattern on the substrate. The metal powder is compressed by the projections of the die, thereby densifying the powder and causing it to adhere to the adhesive in a reproduction of the die pattern. The metal powder does not adhere substantially in uncompressed regions, and may be removed. In this manner, a metal powder composition may be densified and adhered to a substrate forming a web of flexible circuit elements, for example, circuit elements such as antennas, resistors, capacitors, inductive coils, conduction pads and the like.

Claims

1. A process comprising:

applying an adhesive layer to a first surface of a flexible substrate;

applying a metal powder to the adhesive layer; and

compressing the metal powder on the adhesive layer for a time and at a pressure sufficient to form a pattern of densified adhered metal powder.

2. The process of claim 1, wherein compressing comprises applying a pressure to the metal powder to densify the metal powder to less than 100% dense.

3. The process of claim 1, wherein compressing comprises compressing the metal powder with a patterned die to form the pattern corresponding to raised elements of the patterned die.

4. The process according to claim 1, further comprising removing uncompressed metal powder from the adhesive layer.

5. The process according to claim 1, wherein the compressed metal powder exhibits a resistivity from about 2 to about 50 microohm-cm.

6. The process according to claim 1, further comprising:

applying a second adhesive layer to a second surface of a flexible substrate;

applying a metal powder to the second adhesive layer;

compressing the metal powder on the second adhesive layer on the second surface with a patterned die having raised elements in the form of a pattern, for a time and at a pressure sufficient to densify the metal powder to at least about 90% and at most less than 100% dense in a pattern corresponding to the raised elements of the patterned die; and

removing uncompressed metal powder from the second adhesive layer.

7. The process according to claim 1, further comprising applying an overlayer covering at least a portion of the densified metal powder.