Stretchable polymer thick film compositions for thermoplastic substrates and wearables electronics

• US 10,072,177 B2
• Filed: 11/02/2015
• Issued: 09/11/2018
• Est. Priority Date: 11/06/2014
• Status: Active Grant

• Current Assignee: Du Pont China Limited (DuPont de Nemours, Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Burrows, Michael Zanoni, Critzer, Mark Steven, Dorfman, Jay Robert
• Primary Examiner(s): McGinty, Douglas J
• Application Number:
  US14/929,498
• Publication Number:
  US 20160130471A1
• Time in Patent Office: 1,044 Days
• Field of Search: 252511, 252514, 252 623 Q, 174251, 174257, 524590
• CPC Class Codes: C08K 2003/0806 Silver
• CPC Class Codes: C08K 3/08 Metals
• CPC Class Codes: C08K 3/36 Silica
• CPC Class Codes: C09D 175/08 from polyethers
• CPC Class Codes: C09D 5/24 Electrically-conducting paints conductive materials H01B1/00
• CPC Class Codes: H01B 1/22 the conductive material comprising metals or alloys
• CPC Class Codes: H05K 1/0283 Stretchable printed circuits
• CPC Class Codes: H05K 1/0326 containing O
• CPC Class Codes: H05K 1/0346 containing N
• CPC Class Codes: H05K 1/09 Use of materials for the conductive, e.g. metallic pattern
• CPC Class Codes: H05K 1/095 for polymer thick films, i.e. having a permanent organic polymeric binder
• CPC Class Codes: H05K 2201/0129 Thermoplastic polymer, e.g. auto-adhesive layer; Shaping of thermoplastic polymer

Abstract

This invention is directed to stretchable polymer thick film compositions useful for wearable garments. More specifically, the polymer thick film may be used in applications where significant stretching is required, particularly on substrates that can be highly elongated. A particular type of substrate is a thermoplastic polyurethane substrate.

Claims

1. A polymer thick film encapsulant paste composition comprising:

(a) fumed silica; and

(b) an organic medium comprising 5-50 wt % thermoplastic polyurethane resin dissolved in an organic solvent, said thermoplastic polyurethane resin having a per cent elongation of at least 200% and a tensile stress necessary to achieve 100% elongation of less than 1000 psi, wherein the weight percent is based on the total weight of said organic medium.

2. The polymer thick film encapsulant paste composition of claim 1, said polymer thick film encapsulant paste composition comprising 0.1 to 3 wt % fumed silica and 97 to 99.9 wt % organic medium, wherein the wt % are based on the total weight of said composition and wherein said thermoplastic polyurethane resin is selected from the group consisting of a polyester-based polymer, a urethane homopolymer and a predominantly linear hydroxyl polyurethane.