Disclosed is a resin composition, which comprises 30 parts by weight to 90 parts by weight of a maleimide resin and 15 parts by weight to 60 parts by weight of a benzoxazine resin. The resin composition may be fabricated into various articles, such as prepregs, prepregs with copper foil, resin films, resin films with copper foil, laminates or printed circuit boards, which possess at least one, more or all of the following properties: high peel strength, high thermal resistance after moisture absorption, high glass transition temperature, low thermal expansion, high thermal resistance, low dielectric constant, low dissipation factor and so on.

The purpose of the present invention is to provide a prepreg which satisfies one of a)-c): a) having superior storage stability and capable of providing a fiber-reinforced composite material having superior mechanical properties; b) capable of providing a fiber-reinforced composite material having superior mechanical properties, and the obtained fiber-reinforced composite material has superior appearance quality; and c) having superior storage stability, generating less amount of heat when cured, and enabling the cure extent and the viscosity in the B-stage state to be flexibly controlled. To achieve the purpose, the present invention provides a prepreg including reinforced fibers and an epoxy resin composition which contains an epoxy resin and a curing agent represented by a specific chemical formula, and which satisfies a specific condition.

The present invention provides a prepreg for a coreless substrate including a thermosetting resin composition containing (a) (meth)acrylic elastomer, (b) an amine compound having at least two primary amino groups, and (c) a maleimide compound having at least two N-substituted maleimide groups, and a coreless substrate using the same, a method of manufacturing the coreless substrate, and a semiconductor package.

The resin composition includes: an epoxy resin as Component (A); a phenolic compound as Component (B); and an imidazole compound having a triazine skeleton, as Component (C). A cured product of the resin composition has a glass transition temperature of 260 C. or more.

An epoxy resin composition for fiber reinforced composite materials comprising components (A) to (E): component (A), an epoxy resin; component (B), a dicyandiamide or a derivative thereof; component (C), a polyisocyanate compound; component (D), a urea compound as represented by formula (1):

##STR00001##

(wherein R.sup.1 and R.sup.2 are each independently H, CH.sub.3, OCH.sub.3, 0C.sub.2H.sub.5, NO.sub.2, halogen, or NHCO NR.sup.3R.sup.4; and R.sup.3 and R.sup.4 are each independently a hydrocarbon group, allyl group, alkoxy group, alkenyl group, aralkyl group, or an alicyclic compound containing both R.sup.3 and R.sup.4, all containing 1 to 8 carbon atoms); and component (E), at least one compound selected from the group consisting of quaternary ammonium salts, phosphonium salts, imidazole compounds, and phosphine compounds.

A soft magnetic resin composition contains flat soft magnetic particles, and a resin component containing an epoxy resin, a phenol resin, and an acrylic resin. The epoxy resin consists of only an epoxy resin having three or more functional groups, the phenol resin consists of only a phenol resin having three or more functional groups, and the content ratio of the acrylic resin in the resin component is 25 mass % or more.

The present invention provides a prepreg for a coreless substrate including a thermosetting resin composition containing (a) (meth)acrylic elastomer, (b) an amine compound having at least two primary amino groups, and (c) a maleimide compound having at least two N-substituted maleimide groups, and a coreless substrate using the same, a method of manufacturing the coreless substrate, and a semiconductor package.

A resin composition is provided. The resin composition comprises an epoxy resin (A) and a first hardener (B) of the following formula (I): ##STR00001##
wherein Ar, R and n are as defined in the specification, and the molar ratio of the epoxy group of the epoxy resin to the active functional group of the first hardener ranges from about 1:0.4 to about 1:1.6.

The disclosure relates to a resin composition, comprising an epoxy resin, a high molecular weight polyetheramine and an amine-terminated acrylonitrile rubber. Various products can be made from the resin composition, such as prepregs, laminates, printed circuit boards or rigid-flex boards, in which one, multiple or all of the following properties can be met: low resin flow, low dust weight loss, high peel strength at room temperature and at high temperature, low moisture absorption rate, and better varnish stability.

The present invention relates to a process for preparing a resin composition comprising benzoxazine, a prepreg and a laminate prepared therefrom. Said resin composition comprising benzoxazine is prepared by adding an acidic filler into the resin composition comprising benzoxazine, wherein said resin composition comprising benzoxazine comprises a benzoxazine resin, an epoxy resin A1 having an epoxy equivalent of 150-450, and an epoxy resin A2 having an epoxy equivalent of 451-1000. By adding an acidic filler into the resin composition, the present invention promotes the polymerization of benzoxazine and epoxy resins, and decreases the curing temperature needed for the polymerization of benzoxazine and epoxy resins. The laminates prepared from the resin composition added with an acidic filler have a high anti-stripping stability, a high glass transition temperature, a low water absorption, a high heat resistance, a high bending strength and a better processability, and achieves a low coefficient of thermal expansion.