Gasket for liquid crystal light shutter displays

• US 3,994,568 A
• Filed: 09/13/1973
• Issued: 11/30/1976
• Est. Priority Date: 09/13/1973
• Status: Expired due to Term

• Current Assignee: Hoffmann-La Roche Incorporated (Roche Holding AG)
• Original Assignee: Hoffmann-La Roche Incorporated (Roche Holding AG)
• Inventors: King, Harry A., Washick, John M.
• Primary Examiner(s): Bauer, Edward S.
• Application Number:
  US05/396,788
• Time in Patent Office: 1,174 Days
• Field of Search: 161/165, 161/185, 161/186, 161/192, 161/203, 350/160 LC
• US Class Current: 349/154
• CPC Class Codes: G02F 1/1339 Gaskets; Spacers; Sealing of cells

Abstract

A gasket for liquid crystal light shutter displays, particularly field effect light shutter displays, comprising a high molecular weight thermoplastic resin, preferably a phenoxy polymer resin, which is not reactive with nor soluble in the liquid crystal material but which will bond two transparent plates together securely and restrict the flow of moisture or other contaminants from the atmosphere into a liquid crystal film disposed between the transparent plates.

Claims

1. In a liquid crystal light shutter, the combination of a layer of liquid crystal material sandwiched between transparent parallel plates, and a gasket surrounding said layer of liquid crystal material and bonding said plates together, said gasket being formed from an essentially thermoplastic phenoxy polymer resin which is neither reactive with nor soluble in the liquid crystal material and which will hold said parallel plates securely together while providing a seal around said layer of

2. The combination of claim 1 wherein said gasket is formed from a phenoxy polymer resin having the following molecular structure:

##SPC2##

3. The combination of claim 2 wherein the resin has a molecular weight of

4. The combination of claim 3 wherein said gasket is formed by

5. The combination of claim 4 wherein said resin is mixed with a modifier, a solvent, fumed silica and an organo-silicon compound before being

6. The combination of claim 5 wherein said resin is mixed before silk-screening to form the following mixture:

space="preserve" listing-type="tabular">______________________________________ Parts by Constituent Weight ______________________________________ resin 2-10 modifier 0-10 solvent 5-30 fumed silica 0-1 organo-silicon compound 0-1 ______________________________________

7. The combination of claim 6 wherein said constituents are present in parts by weight as follows:

resin -- 10, modifier -- 0.5, solvent --

8. In a liquid crystal light shutter, the combination of a layer of liquid crystal material sandwiched between transparent parallel plates, and a gasket surrounding said layer of liquid crystal material and bonding said plates together, said gasket being formed from an essentially thermoplastic phenoxy polymer resin which is neither reactive with nor soluble in the liquid crystal material and which will hold said parallel plates securely together while providing a seal around said layer of liquid crystal material, as is formed by silk-screening onto at least one of said transparent parallel plates a mixture comprising about 2 to 10 parts by weight of said resin, 0 to 10 parts by weight of a modifier, 5 to 30 parts by weight of a solvent, 0 to 1 part by weight fumed silica and 0 to 1% by weight of an organo-silicon compound, the transparent parallel plates being pressed together after application of said mixture in the form of a gasket with a layer of liquid crystal material between the transparent plates, whereupon said solvent is permitted to evaporate to form a bond between said plates with the liquid crystal material therebetween.