Method of making bondable flexible printed circuit

• US 8,127,440 B2
• Filed: 08/29/2007
• Issued: 03/06/2012
• Est. Priority Date: 10/16/2006
• Status: Expired due to Fees

• Current Assignee: Joel S. Douglas
• Original Assignee: Joel S. Douglas
• Inventors: Douglas, Joel S.
• Primary Examiner(s): CAZAN, LIVIUS RADU
• Application Number:
  US11/897,077
• Publication Number:
  US 20080086876A1
• Time in Patent Office: 1,651 Days
• Field of Search: 298/46, 298/42, 252/502, 174/254, 174/257
• US Class Current: 29/846
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: H05K 1/095 for polymer thick films, i.e. having a permanent organic polymeric binder
• CPC Class Codes: H05K 2201/026 Nanotubes or nanowires
• CPC Class Codes: H05K 2201/0323 Carbon
• CPC Class Codes: H05K 2203/0285 Using ultrasound, e.g. for cleaning, soldering or wet treatment
• CPC Class Codes: H05K 3/245 Reinforcing conductive patterns made by printing techniques or by other techniques for applying conductive pastes, inks or powders; Reinforcing other conductive patterns by such techniques
• CPC Class Codes: H05K 3/328 by welding
• CPC Class Codes: H05K 3/361 Assembling flexible printed circuits with other printed circuits
• CPC Class Codes: H05K 3/363 by soldering
• CPC Class Codes: Y10T 29/49124 On flat or curved insulated base, e.g., printed circuit, etc.
• CPC Class Codes: Y10T 29/49126 Assembling bases
• CPC Class Codes: Y10T 29/49147 Assembling terminal to base
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base

Abstract

A method for producing a circuit assembly having a non-conductive substrate upon which printed conductors may be easily and selectively interconnected to another circuit assembly device, and/or apparatus.

Claims

1. A method of making a bondable flexible printed circuit, said method comprising the steps of:

providing a non-conductive substrate;

applying to said substrate at least one conductive wet dispersion layer containing carbon nanotubes, larger diameter conductive particles having at least one dimension of at least 100 nanometers which are not carbon nanotubes, and a polymer to form a conductor of a not cured printed circuit;

curing said not cured printed circuit with heat so that said polymer is cured to form a surface, the cured printed circuit having said carbon nanotubes oriented in a three-dimensional matrix with said larger conductive particles, with at least a portion of said carbon nanotubes protruding above said cured polymer surface; and

bonding a second conductor to said carbon nanotubes protruding from said cured polymer surface.

2. A method of claim 1 where the bonding step is performed using ultrasonic welding.

3. A method of claim 1 where the bonding step is performed using soldering.

4. A method of claim 1 where the dispersion of carbon nanotubes is refined by flocculation so as to remove unusable flocs of nanotubes.