Abstract: The present invention provides an epoxy resin composition that contains an epoxy resin (A) that is a product of reaction between an epihalohydrin and either catechol, optionally with its aromatic ring methyl-substituted, or pyrogallol, optionally with its aromatic ring methyl-substituted, and an aromatic glycidylamine epoxy resin (B). This epoxy resin composition is suitable for use in fiber-reinforced composite materials, fiber-reinforced plastic articles, etc., by virtue of being liquid at room temperature, being superior in quick curing, and high mechanical properties in its cured form.

Abstract: The present invention provides: a two-pack curable epoxy resin composition that contains a curing agent having excellent long-term storage stability, has a low viscosity and a good impregnation property into fibers; the cured product; a fiber-reinforced composite material; and a molded article. Specifically, the two-pack curable epoxy resin composition is used, the two-pack curable epoxy resin composition containing: a main agent (i) containing an epoxy resin (A); and a curing agent (ii) containing an acid anhydride (B) and an organic phosphorus compound (C), in which a mass ratio [(i)/(ii)] of the main agent (i) to the curing agent (ii) is in a range of 35/65 to 75/25, and an amount of the organic phosphorus compound (C) used is in a range of 0.5 to 5 parts by mass with respect to 100 parts by mass in total of the epoxy resin (A) and the acid anhydride (B).

Abstract: The present invention provides an epoxy resin including a reaction product of 1,2,4-trihydroxybenzene and an epihalohydrin, the epoxy resin containing a cyclic compound that has a cyclic structure containing, as constitutional atoms, oxygen atoms at 1-position and 2-position derived from 1,2,4-trihydroxybenzene, the cyclic compound being contained in an amount of 0.003 to 0.070 mol based on 100 g of the epoxy resin. The epoxy resin is liquid and is excellent in pyrolysis resistance.

Abstract: The present invention provides an epoxy resin including a reaction product of 1,2,3-trihydroxybenzene and an epihalohydrin, the epoxy resin containing a cyclic compound that has acyclic structure containing, as constitutional atoms, two adjacent oxygen atoms derived from 1,2,3-trihydroxybenzene, the cyclic compound being contained in an amount of 0.040 to 0.115 mol based on 100 g of the epoxy resin. The epoxy resin can be an alternative as a biobased polymer, is liquid, and is excellent in thermal resistance.

Abstract: The present invention provides an epoxy resin including a reaction product of 1,2,4-trihydroxybenzene and an epihalohydrin, the epoxy resin containing a cyclic compound that has a cyclic structure containing, as constitutional atoms, oxygen atoms at 1-position and 2-position derived from 1,2,4-trihydroxybenzene, the cyclic compound being contained in an amount of 0.003 to 0.070 mol based on 100 g of the epoxy resin. The epoxy resin is liquid and is excellent in pyrolysis resistance.

Abstract: The present invention provides an epoxy resin composition that contains an epoxy resin (A) that is a product of reaction between an epihalohydrin and either catechol, optionally with its aromatic ring methyl-substituted, or pyrogallol, optionally with its aromatic ring methyl-substituted, and an aromatic glycidylamine epoxy resin (B). This epoxy resin composition is suitable for use in fiber-reinforced composite materials, fiber-reinforced plastic articles, etc., by virtue of being liquid at room temperature, being superior in quick curing, and high mechanical properties in its cured form.

Abstract: The present invention provides an epoxy resin including a reaction product of 1,2,3-trihydroxybenzene and an epihalohydrin, the epoxy resin containing a cyclic compound that has acyclic structure containing, as constitutional atoms, two adjacent oxygen atoms derived from 1,2,3-trihydroxybenzene, the cyclic compound being contained in an amount of 0.040 to 0.115 mol based on 100 g of the epoxy resin. The epoxy resin can be an alternative as a biobased polymer, is liquid, and is excellent in thermal resistance.

Abstract: A pouch of the present invention comprises a front and a rear walls and a narrow pouring portion, and at least one wall portion is partially protruded to an outward direction of the pouch to be provided with a bulge portion having a hollow structure at vicinity of the pouring portion. Alternatively, a cut line of the pouring portion is positioned based on a vertex of a vertical angle of an assumed right triangle which is drawn at the pouring portion by the predetermined regulations. A half-cut line as an opening aid may be provided to a position to be opened of the pouch, the half-cut line being formed so as to have a combination of a deep part and a shallow part and/or a combination of a wide part and a narrow part. The bulge portion may be formed by subjecting a preheated resin film to press molding with the use of a die comprising a cavity and a core, and then cooling the thus press-molded resin film while it is held in the die.