Sealing agent for plastic liquid crystal display panels

• US 4,325,610 A
• Filed: 09/30/1980
• Issued: 04/20/1982
• Est. Priority Date: 02/01/1979
• Status: Expired due to Term

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Watch Company Limited
• Inventors: Inoue, Hiroshi
• Primary Examiner(s): Schofer, Joseph L.
• Assistant Examiner(s): Lipman, Bernard
• Application Number:
  US06/214,003
• Time in Patent Office: 567 Days
• Field of Search: 260/33.4 EP, 260/31.2 XA, 260/32.4, 260/32.8 EP, 260/33.8 EP, 525/423, 525/424, 525/438, 525/440, 350/343
• US Class Current: 349/190
• CPC Class Codes: C08G 59/4028 Isocyanates; Thioisocyanates
• CPC Class Codes: C08L 2666/14 Macromolecular compounds according to C08L59/00 - C08L87/00; Derivatives thereof
• CPC Class Codes: C08L 63/00 Compositions of epoxy resins; Compositions of derivatives of epoxy resins
• CPC Class Codes: C08L 67/02 Polyesters derived from dicarboxylic acids and dihydroxy compounds C08L67/06 takes precedence
• CPC Class Codes: C08L 75/00 Compositions of polyureas or polyurethanes; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 77/00 Compositions of polyamides obtained by reactions forming a carboxylic amide link in the main chain of polyhydrazides C08L79/06; of polyamideimides or polyamide acids C08L79/08; Compositions of derivatives of such polymers
• CPC Class Codes: C09J 163/00 Adhesives based on epoxy resins; Adhesives based on derivatives of epoxy resins
• CPC Class Codes: C09J 167/02 Polyesters derived from dicarboxylic acids and dihydroxy compounds C09J167/06 takes precedence
• CPC Class Codes: C09J 177/00 Adhesives based on polyamides obtained by reactions forming a carboxylic amide link in the main chain based on polyhydrazides C09J179/06; based on polyamide-imides C09J179/08; Adhesives based on derivatives of such polymers
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• CPC Class Codes: G02F 1/1339 Gaskets; Spacers; Sealing of cells
• CPC Class Codes: Y10S 359/90 Methods

Abstract

A sealing agent for plastic liquid crystal display panels which comprises the following three effective components:

(a) Nylon and/or a linear saturated polyester;

(b) an epoxy resin and/or an isocyanate compound; and

(c) a solvent which can dissolve the components (a) and (b), and a transparent plastic panel substrate.

The sealing agent makes it possible to use a transparent plastic film as a substrate for a liquid crystal display panel, thereby enabling inexpensive mass-production of high quality liquid crystal display panels.

Claims

1. A method of sealing a liquid crystal display panel comprising:

applying sealant to at least one of separated upper and lower transparent plastic panel substrates, drying said sealant to effect preliminary solidification of said sealant,

depositing a liquid crystal within one of the panel substrates,

hot press sealing the two panel substrates and curing the sealed portion at a temperature above the melting point of the plastic substrates but below the thermal deformation temperature of the substrates.

2. The sealing method of claim 1, wherein the sealant for the plastic liquid crystal display panels comprises the following three components:

(a) nylon and/or a linear saturated polyester;

(b) an epoxy resin and/or an isocyanate compound; and

(c) a solvent which can dissolve the components (a) and (b), and can also dissolve said transparent plastic panel substrates.

3. The sealing method of claim 2, wherein said component (c) comprises 1,1,1,3,3,3-hexafluoro-2-propanol.

4. The sealing method of claim 2, wherein said nylon and linear saturated polyester have a melting point of 60°

C. to 150°

C.

5. The sealing method of claim 2, wherein said epoxy resin has a molecular weight of 130 to 1,260.

6. The sealing method of claim 2, wherein said components (a) and (b) have the following ratio:

Component (a);

component (b)=2.5 to 3;

1.