Seal for liquid crystal display

• US 4,695,490 A
• Filed: 10/15/1985
• Issued: 09/22/1987
• Est. Priority Date: 10/15/1985
• Status: Expired due to Fees

• Current Assignee: RCA Corporation
• Original Assignee: RCA Corporation
• Inventors: Desai, Nitin V., McClelland, Sandra K., Conrad, Neal D.
• Primary Examiner(s): Foelak, Morton
• Application Number:
  US06/787,679
• Time in Patent Office: 707 Days
• Field of Search: 350/343, 428/1, 428/192, 428/343
• US Class Current: 428/1.53
• CPC Class Codes: C08G 59/502 Polyalkylene polyamines
• CPC Class Codes: C09J 163/00 Adhesives based on epoxy resins; Adhesives based on derivatives of epoxy resins
• CPC Class Codes: C09K 2323/055 Epoxy
• CPC Class Codes: G02F 1/1341 Filling or closing of cells
• CPC Class Codes: Y10T 428/24777 Edge feature
• CPC Class Codes: Y10T 428/28 Web or sheet containing structurally defined element or component and having an adhesive outermost layer

Abstract

A sealant composition to seal the fill port in a liquid crystal display is disclosed. The subject composition is comprised of a diglycidylether of bisphenol A epoxy precursor, a curing agent therefor and, optionally, a minor amount of a thixotropic agent.

Claims

1. In a liquid crystal display comprising two spaced apart substrates sealed at the periphery with the exception of one or more fill ports, liquid crystal material disposed between the substrates and a sealant for the fill ports, the improvement wherein the sealant comprises a cured epoxy resin of a diglycidylether of bisphenol A precursor represented by the formula ##STR2## wherein n is 0-2, a curing agent hardener therefor comprising triethylenetetramine and, optionally, a minor amount of a suitable thixotropic agent.

2. A liquid crystal display in accordance with claim 1, wherein the precursor is a mixture of from about 82 to about 86 percent by weight of a compound represented by the formula wherein n is zero, from about 5 to about 9 percent by weight of a compound represented by the formula wherein n is 1 and from about 7 to about 11 percent of a compound represented by the formula wherein n is 2.

3. A liquid crystal display in accordance with claim 1, wherein the periphery of the substrates exclusive of the fill ports is sealed with said sealant composition.

4. A liquid crystal display in accordance with claim 1, wherein the sealant composition contains from about 13 to about 16 parts by weight of the curing agent for each 100 parts by weight of the precursor.

5. A liquid crystal display in accordance with claim 1, wherein the liquid crystal material is a twisted nematic liquid crystal.

6. A liquid crystal display in accordance with claim 1, wherein the thixotropic agent is finely divided silica.