# US 5,350,826 A · Epoxy resin composition containing a polyaminoamide and a latent curing agent for fiber impregnation

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- Number: US 5,350,826 A
- Document ID: US5350826A
- Status: Granted
- Kind: A
- Application number: 07/982,722
- Filed: 1992-11-27
- Granted: 1994-09-27
- Earliest claimed: 1991-11-29
- Assignees: Tonen Corporation
- Inventors: Osamu Watanabe; Makoto Takezawa
- Web page: https://patentgrep.com/patent/US5350826A

## CPC

- C08L 63/00: Compositions of epoxy resins; Compositions of derivatives of epoxy resins
- C08J 5/244: {using glass fibres}
- C08J 2363/00: Characterised by the use of epoxy resins; Derivatives of epoxy resins
- Y10S 525/935: Matrix admixed with synthetic fiber
- C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06)
- C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29)
- Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

## Abstract

An epoxy resin composition for forming prepregs is disclosed which includes an epoxy resin having at least two epoxy groups, a latent curing agent for the epoxy resin in an amount of 0.5-3.0 equivalents per equivalent of the epoxy groups of the epoxy resin, and a reactive, viscosity-increasing agent in an amount of 0.2-3.0 parts by weight per 100 parts by weight of the epoxy resin. The epoxy resin composition has an initial viscosity n.sub.I(50) at 50.degree. C. of 1,000-200,000 cP and an initial viscosity n.sub.I(23) at 23.degree. C. of at least 10,000 cP.

## Claims

### Claim 1

An epoxy resin composition comprising:
an epoxy resin having at least two epoxy groups;
a latent curing agent for said epoxy resin in an amount of 0.5-3.0 equivalents per equivalent of the epoxy groups of said epoxy resin said latent curing agent having a reaction initiation temperature of 40.degree.-115.degree. C.; and
a reactive, viscosity-increasing agent selected from the group consisting of aromatic diamines and polyaminoamides, said reactive, viscosity-increasing agent being present in an amount of 0.2-3.0 parts by weight per 100 parts by weight of said epoxy resin, said epoxy resin composition having an initial viscosity n.sub.I (50) at 50.degree. C. of 1,000-200,000 cP and an initial viscosity n.sub.I (23) at 23.degree. C. of at least 10,000 cP, said reactive viscosity-increasing agent serving to increase said initial viscosity n.sub.I (50) to 50,000-1,500,000 cP when maintained at 23.degree. C. for 7 days, said composition exhibiting a viscosity at 50.degree. C. of no more than 50 times the initial viscosity n.sub.I (50) when maintained at 23.degree. C. for 7 days.

### Claim 2 (depends on 1)

A composition as claimed in claim 1, further comprising a silane coupling agent having an epoxidized cycloalkane, a glycidoxy group or an amino group.

### Claim 3 (depends on 1)

A composition as claimed in claim 1, further comprising a nitrile rubber.

### Claim 4 (depends on 1)

A composition as claimed in claim 1, and exhibiting a viscosity at 50.degree. C. of 50,000-1,500,000 when maintained at 23.degree. C. for 7 days.

### Claim 5 (depends on 1)

A prepreg comprising a layer of a reinforcing fiber impregnated with an epoxy resin composition according to claim 1.