A flux resin composition includes an epoxy resin, an imidazole compound, a thixo agent, and an activator. The epoxy resin includes at least one resin selected from the group consisting of naphthalene epoxy resins, biphenyl aralkyl epoxy resins, trisphenol methane epoxy resins, biphenyl epoxy resins, and dicyclopentadiene epoxy resins. The content of the at least one resin is equal to or greater than 20% by weight with respect to a total weight of the epoxy resin.

An object of the present invention is to provide an epoxy amine adduct, a curing catalyst, a resin composition, a sealing material, an adhesive agent, and a cured product, which have good characteristics. There is prepared an epoxy amine adduct in which a value of (melting onset temperature at a temperature increasing rate of 50° C./min)/(melting onset temperature at a temperature increasing rate of 10° C./min) in differential scanning calorimetry (DSC) is 1.00 or more and 1.10 or less. There are prepared a curing catalyst for epoxy resin containing the epoxy amine adduct, a resin composition containing the curing catalyst, a sealing material or an adhesive agent each containing the resin composition, and a cured product obtained by curing the resin composition.

The present application provides a rapid curing epoxy resin composition for fiber-reinforced plastic materials that can be used with modern fast-cure heating systems without loss of heat resistance, surface quality, or mechanical properties of the cured epoxy matrix composite as well as prepregs and fiber-reinforced plastic materials based thereon as their matrix resins. The epoxy resin composition includes an epoxy resin, a dicyandiamide, an aromatic urea, and a clathrate complex comprising at least one compound selected from the group consisting of carboxylic acid compounds and tetrakisphenol compounds and at least one epoxy accelerator which is an imidazole and/or imidazoline.

Provided are a white heat-curable epoxy resin composition capable of yielding a cured product that is tough and superior in initial reflection rate and heat resistance; and a semiconductor device with a light receiving element and other semiconductor elements being encapsulated by such cured product. The white heat-curable epoxy resin composition contains: (A) a prepolymer as a molten mixture of (A-1) an epoxy resin: a triazine derivative epoxy resin and/or an alicyclic epoxy compound having an epoxy group and an alicyclic structure in one molecule and being non-fluid at 25° C., (A-2) an acid anhydride having no carbon-carbon double bond and (A-3) an acrylic resin-based modifier having an epoxy group and a weight-average molecular weight of 1,000 to 30,000; (B) a white pigment containing a titanium oxide; (C) an inorganic filler; (D) a curing accelerator; and (E) an antioxidant.

An epoxy resin composition for a fiber-reinforced composite material includes: (a) one or more epoxy resins; (b) an aromatic diamine compound; (c) a dicyandiamide; (d) a urea compound; and (e) an amine adduct compound, blended in specific ranges.

Provided is a method for degrading epoxy resins by enzymatic route, in particular by adding an epoxy resin in a solvent followed by treatment with a glutathione S-transferase. A method for recycling a composite material comprising epoxy resin as well as the use of glutathione 5-transferase and eventually para-hydroxybenzoate hydroxylase for degrading epoxy resins are also provided.

A curable composition that can be cured at low temperature in a short time regardless of the type of epoxy compound that is mixed therewith, and has a long pot life; an adhesive comprising said curable composition; a method for producing a fiber-reinforced composite material that uses the curable composition; and a fiber-reinforced composite material containing a matrix comprising the curable composition. A curing agent mixture composition that can be cured at low temperature and in a short time, and provides the curable composition with a long pot life. An epoxy compound (A) and an imidazole compound (B) are blended in with the curable composition. In addition, the imidazole compound (B) and at least one type of crosslinking agent (C) are blended in with the curing agent mixture composition.

The present invention provides an epoxy resin-based curable composition which may be used as a structural adhesive for an automobile. Particularly, the present invention provides an epoxy resin-based curable composition having excellent low-temperature curability, while maintaining good storage stability and good adhesion. The present invention relates to a curable composition comprising an epoxy resin, a urea-based curing accelerator (A) and an amine-based curing agent (B) having a pyrazine ring.

The present invention relates to an adhesive resin composition including a styrene-ethylene-butylene-styrene copolymer with a specific chemical structure, an epoxy resin, an acid anhydride compound, and a curing catalyst, an adhesive film obtained from the resin composition, and a flexible metal laminate including the adhesive film.

Provided are: an epoxy resin composition for fiber-reinforced composite materials, which has a good balance between storage stability and fast curing properties at high levels; a prepreg; and an epoxy resin composition which exhibits excellent mechanical characteristics as a fiber-reinforced composite material. A resin composition which contains an epoxy resin, dicyandiamide, an imidazole compound and an acidic compound, while satisfying the following conditions (a)-(c): (d) The time until the heat flow rate reaches the peak top after the epoxy resin composition reaches 100° C. is 25 minutes or less as measured by a differential scanning calorimeter at an isothermal temperature of 100° C. in a nitrogen gas stream. (e) The time until the heat flow rate reaches the peak top after the epoxy resin composition reaches 60° C. is 15 hours or more as measured by a differential scanning calorimeter at an isothermal temperature of 60° C. in a nitrogen gas stream. (f) The ratio of the number of epoxy groups to the number of imidazole rings in the epoxy resin composition is from 25 to 90 (inclusive).