High transmission light control film

Patent metadata

Field	Value
Publication number	US-12372693-B2
Application number	US-202318536915-A
Country	US
Kind code	B2
Filing date	Dec 12, 2023
Priority date	Dec 13, 2017
Publication date	Jul 29, 2025
Grant date	Jul 29, 2025

Abstract

A light control film comprises a light input surface and a light output surface opposite the light input surface. Alternating transmissive regions and absorptive regions are disposed between the light input surface and the light output surface. The absorptive regions have an aspect ratio of at least 30 and the alternating transmissive region and absorptive regions have a relative transmission at a viewing angle of 0 degrees of at least 75%.

First claim

What is claimed is:

1. A method of making a light control film comprising:
providing a microstructured film comprising a plurality of light transmissive regions alternated with channels, wherein the microstructured film has a surface defined by a top surface and side walls of the light transmissive regions and a bottom surface of the channels;
applying an organic light absorptive material to the surface, and
removing at least a portion of the light absorptive material from the top surface of the light transmissive regions and bottom surface of the channels;
wherein the organic light absorptive material comprises polyelectrolytes.

2. The method of claim 1 wherein the organic light absorption material comprises a plurality of light absorbing particles.

3. The method of claim 1 wherein the light absorbing particles have an average particle size of less than 500 nm.

4. The method of claim 1 wherein the step of applying the light absorptive material comprises layer-by-layer self-assembly.

5. The method of claim 1 wherein the step of removing the at least a portion of the light absorptive coating comprises reactive ion etching.

6. The method of claim 1 further comprising filling the channel with an organic polymeric material.

7. The method of claim 6 wherein the organic polymeric material comprises a polymerizable resin and the method further comprising curing the polymerizable resin.

8. A method of making a microstructured film comprising:
providing a microstructured film comprising a plurality of light transmissive regions alternated with channels, wherein the microstructured film has a surface defined by a top surface and side walls of the light transmissive regions and a bottom surface of the channels;
applying a light absorptive material to the surface by layer-by-layer self-assembly;
removing at least a portion of the light absorptive material from the top surface of the light transmissive regions and bottom surface of the channels.

9. The method of claim 8 wherein method further comprises removing at least a portion of the material from the top surface of the protrusions and bottom surface of the channels.

Assignees

• 3M Innovative Properties Company

Inventors

• Schmidt Daniel J
• Nelson Caleb T
• Gotrik Kevin W
• Kenney Raymond J
• Wheatley John A
• Epstein Kenneth A
• Boyd Gary T
• Balts Corey D

Classifications

• G02B2207/123

  Optical louvre elements, e.g. for directional light blocking · CPC title

• G02B6/0053

  Prismatic sheet or layer; Brightness enhancement element, sheet or layer · CPC title

• G02B5/305

  including organic materials, e.g. polymeric layers · CPC title

• G02B5/286

  having four or fewer layers, e.g. for achieving a colour effect · CPC title

• G02B5/208

  for use with infrared or ultraviolet radiation, e.g. for separating visible light from infrared and/or ultraviolet radiation · CPC title