Methods of making metal patterns on flexible substrate

Patent metadata

Field	Value
Publication number	US-11950372-B2
Application number	US-201917252826-A
Country	US
Kind code	B2
Filing date	Jun 27, 2019
Priority date	Jun 28, 2018
Publication date	Apr 2, 2024
Grant date	Apr 2, 2024

Abstract

Methods of making metal patterns on flexible substrates are provided. Releasable solid layer is selectively formed on a patterned surface of the flexible substrate by applying a liquid solution thereon. Metal patterns on the flexible substrate can be formed by removing the releasable solid layer after metallization. In some cases, the releasable solid layer can be transferred from the patterned surface to a transfer layer where the metal patterns are formed.

First claim

What is claimed is:

1. A method of forming a metal pattern on a flexible substrate, the method comprising:
providing a patterned surface on the flexible substrate, the patterned surface including one or more recessed features and one or more plateau features adjacent to the recesses;
treating the patterned surface to form a release coating thereon,
coating a liquid solution on the release coating on the patterned surface to at least partially fill the recessed features and to cover the plateau features;
solidifying the liquid solution to form a releasable solid layer in the recessed features and a solidified product residue on the plateau features, wherein the solidified product residue has a dry thickness at most one-half the thickness of the releasable solid layer in the recessed features;
etching the patterned surface after solidifying the liquid solution to remove the solidified product residue from the plateau features;
providing a metal layer to cover the etched patterned surface; and
removing the releasable solid layer along with the metal layer thereon in the recessed features from the flexible substrate to form a pattern of the metal layer on the plateau features of the flexible substrate;
wherein etching the patterned surface after solidifying the liquid solution further comprises chemically modifying the release coating on the plateau features to increase adhesion to the metal layer.

2. The method of claim 1 , wherein removing the solid layer further comprises overcoating a curable resin on the metal layer and curing the curable resin to form a cured resin layer; and separating the cured resin layer from the flexible substrate to remove the releasable solid layer along with the metal layer thereon in the recessed features from the flexible substrate.

3. The method of claim 1 , wherein providing a patterned surface on the flexible substrate comprises forming micro-replicated features on the flexible substrate.

4. The method of claim 1 , wherein the release coating is formed by a plasma deposition process using hexamethyldisiloxane (HMDSO).

5. The method of claim 1 , wherein the liquid solution comprises poly(vinyl alcohol) (PVA).

6. The method of claim 1 , wherein the metal pattern on the plateau features of the flexible substrate forms a mesh shape having an open area greater than 95%.

7. The method of claim 1 , wherein the patterned surface with the metal pattern thereon is back-filled with a material that is index-matched to the patterned surface.

Assignees

• 3M Innovative Properties Company
• 3M Innovation Properties

Inventors

• Van Lengerich Henrik B
• Stay Matthew S
• Nelson Caleb T
• Tarnowski David J
• Rowe David J
• Kusilek Edwin L

Classifications

• H01B5/14

  comprising conductive layers or films on insulating-supports · CPC title

• H05K3/046

  by selective transfer or selective detachment of a conductive layer · CPC title

• H05K2201/05

  Flexible printed circuits [FPCs] · CPC title

• H05K3/02 Primary

  in which the conductive material is applied to the surface of the insulating support and is thereafter removed from such areas of the surface which are not intended for current conducting or shielding · CPC title

• H05K3/048 Primary

  using a lift-off resist pattern or a release layer pattern · CPC title