IP Library Granted Patent US 12679925
Granted Patent B2
US 12679925 · App. 18/033,094 · Granted Jul 14, 2026

Resin composition, resin cured product, and fiber reinforced resin

Inventors: Takeshi Kondo (Tokyo, JP); Takahito Muraki (Tokyo, JP)
Assignee: HITACHI, LTD.
C08G59/685C08G59/245C08G59/42C08G59/5073C08J5/042C08J5/043C08J5/046C08L63/04
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Quick Facts
Patent No.
US 12679925
App. No.
18/033,094
Granted
Jul 14, 2026
Kind
B2
Abstract

Provided are a resin composition, a resin cured product, and a fiber reinforced resin capable of shortening a stress relaxation time. In order to solve this problem, the resin composition contains an epoxy compound having two or more epoxy groups in a molecule, an acid anhydride, and a complex in which an organic ligand is coordinated to manganese (III). The resin cured product contains a resin having an ester group and a hydroxy group, and a complex in which an organic ligand is coordinated to manganese (III). A fiber reinforced resin 101 contains a resin 1 having an ester group and a hydroxy group, fibers 2 impregnated with at least the resin, and a complex 3 in which an organic ligand is coordinated to manganese (III).

Claims (27)

1 . A resin composition comprising:

an epoxy compound having two or more epoxy groups in a molecule;

an acid anhydride including at least one of phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and derivatives thereof; and

a complex in which an organic ligand is coordinated to manganese (III), the complex contains at least one of manganese (III) acetylacetonate, manganese (III) acetate, and manganese (III) naphthenate,

wherein a content of the complex is 15 mol % or more and 30 mol % or less relative to the epoxy groups, and

wherein a content of the acid anhydride is 40 mol % or more and 70 mol % or less relative to the epoxy groups.

2 . The resin composition according to claim 1 , wherein

the epoxy compound is bisphenol A diglycidyl ether or an epoxy novolac resin.

3 . A resin cured product comprising:

a resin having an ester group and a hydroxy group obtained by a reaction between an epoxy compound having two or more epoxy groups in a molecule and an acid anhydride including at least one of phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and derivatives thereof, wherein a content of the acid anhydride is 40 mol % or more and 70 mol % or less relative to the epoxy groups; and

a complex in which an organic ligand is coordinated to manganese (III), wherein the complex contains at least one of manganese (III) acetylacetonate, manganese (III) acetate, and manganese (III) naphthenate,

wherein a content of the complex is 15 mol % or more and 30 mol % or less relative to the hydroxy group.

4 . The resin cured product according to claim 3 , wherein

when a time during which, based on a stress applied to a test piece containing the resin and the complex, a stress remaining in the test piece decreases to 30% of the applied stress is defined as a stress relaxation time,

the stress relaxation time is 11 min or shorter.

5 . The resin cured product according to claim 4 , wherein

the stress relaxation time is 9 min or shorter.

6 . A fiber reinforced resin comprising:

a resin having an ester group and a hydroxy group obtained by a reaction between an epoxy compound having two or more epoxy groups in a molecule and an acid anhydride including at least one of phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and derivatives thereof, wherein a content of the acid anhydride is 40 mol % or more and 70 mol % or less relative to the epoxy groups;

a fiber impregnated with at least the resin; and

a complex in which an organic ligand is coordinated to manganese (III), wherein the complex contains at least one of manganese (III) acetylacetonate, manganese (III) acetate, and manganese (III) naphthenate,

wherein a content of the complex is 15 mol % or more and 30 mol % or less relative to the hydroxy group.

7 . The fiber reinforced resin according to claim 6 , wherein

the fiber includes at least one of aramid fibers, glass fibers, and carbon fibers.

8 . The resin composition according to claim 1 , wherein a content of the complex is 25 mol % or more and 30 mol % or less relative to the epoxy groups.

9 . The resin cured product according to claim 3 , wherein a content of the complex is 25 mol % or more and 30 mol % or less relative to the epoxy groups.

10 . The fiber reinforced resin according to claim 6 , wherein a content of the complex is 25 mol % or more and 30 mol % or less relative to the epoxy groups.