A prepreg having at least one layer of carbon fibres and a curable thermosetting resin system, the curable thermosetting resin system at least partly impregnating the at least one layer of carbon fibres, wherein the curable thermosetting resin system includes: a curable thermosetting resin including at least one epoxide group, the curable thermosetting resin having an epoxy equivalent weight of from 140 to 180 g/eq; a curing agent for curing the curable thermosetting resin, wherein the curing agent is present in the liquid phase and includes a cyanamide reactive group; and a rheology modifier for the curable thermosetting resin system, wherein the rheology modifier includes at least one of a thermoplastic resin and an inorganic particulate thickener or a mixture thereof.

A prepreg having at least one layer of carbon fibres and a curable thermosetting resin system, the curable thermosetting resin system at least partly impregnating the at least one layer of carbon fibres, wherein the curable thermosetting resin system includes: a curable thermosetting resin including at least one epoxide group, the curable thermosetting resin having an epoxy equivalent weight of from 140 to 180 g/eq; a curing agent for curing the curable thermosetting resin, wherein the curing agent is present in the liquid phase and includes a cyanamide reactive group; and a rheology modifier for the curable thermosetting resin system, wherein the rheology modifier includes at least one of a thermoplastic resin and an inorganic particulate thickener or a mixture thereof.

The present invention relates to a halogen-free epoxy resin composition, a prepreg, a laminate and a printed circuit board containing the same. The halogen-free epoxy resin composition comprises an epoxy resin and a curing agent. Taking the total equivalent amount of the epoxy groups in the epoxy resin as 1, the active groups in the curing agent which react with the epoxy groups have an equivalent amount of 0.5-0.95. By controlling the equivalent ratio of the epoxy groups in the epoxy resin to the active groups in the curing agent to be 0.5-0.95, the present invention ensures the Df value stability of prepregs under different curing temperature conditions while maintaining a low dielectric constant and a low dielectric loss. The prepregs and laminates prepared from the resin composition have comprehensive performances, such as low dielectric constant, low dielectric loss, excellent flame retardancy, heat resistance, cohesiveness, low water absorption and moisture resistance, and are suitable for use in halogen-free multilayer circuit boards.

A silicone oil-treated fumed silica and a method of producing the silicone oil-treated fumed silica are provided. The silicone oil-treated fumed silica, which has the following physical properties: A) the silicone oil-treated fumed silica has a degree of hydrophobicity of 68 vol % or more; B) the silicone oil-treated fumed silica has a silicone oil fixation rate of from 60 mass % to 95 mass %; and C) a composition obtained by adding 6 parts by mass of the silicone oil-treated fumed silica to 100 parts by mass of an amine composition containing trimethylolpropane polyoxypropylene triamine and 1,3-bis(aminomethyl)cyclohexane at a mass ratio of 95:5 has a viscosity of 4,000 mPa.Math.s or more after the composition is left to stand at 25° C. for 1 hour.

The present invention provides thermosetting resin pre-impregnated or infused fiber materials or prepregs comprising a thermosetting resin mixture and a fiber material component of a heat resistant fiber, such as carbon fiber, having an areal weight of from 500 to 3,000 g/m2 having a coating of from 0.5 to 4 phr of a latent, particulate curative or solid curative, preferably, dicyandiamide, wherein the prepregs are infused with a thermosetting resin mixture comprising (a) at least one liquid epoxy resin, and (b) a hardener and/or a catalyst, as well as methods of making the same. The prepregs of present invention enables the simple provision of lightweight composites having consistent resin cure throughout.

Water-borne cross-linking polymeric compositions and related embodiments, such as methods of making and using the compositions, as well as products formed with said compositions are described. For example, the water-borne composition may comprise polymers incorporating cross-linking functionality such as, but not limited to, carbonyl or epoxy functionality, and a blocked cross-linking agent, for example, a hydrazone. The cross-linking functionality does not react with the blocked cross-linking agent; however, the blocked cross-linking agent is capable of reacting with the alternative form cross-linking agent such as, but not limited to, a hydrazide, to yield a cross-linked polymer. The alternative form cross-linking agent may be formed in an equilibrium reaction including the blocked cross-linking agent.

To provide a composition for a three-dimensional integrated circuit capable of forming a filling interlayer excellent in thermal conductivity also in a thickness direction, using agglomerated boron nitride particles excellent in the isotropy of thermal conductivity, disintegration resistance and kneading property with a resin. A composition for a three-dimensional integrated circuit, comprising agglomerated boron nitride particles which have a specific surface area of at least 10 m.sup.2/g, the surface of which is constituted by boron nitride primary particles having an average particle size of at least 0.05 μm and at most 1 μm, and which are spherical, and a resin (A) having a melt viscosity at 120° C. of at most 100 Pa.Math.s.

A method for surface preparation of composite substrates prior to adhesive bonding. A curable surface treatment layer is applied onto a curable, resin-based composite substrate, followed by co-curing. After co-curing, the composite substrate is fully cured but the surface treatment layer remains partially cured. The surface treatment layer may be a resin film or a removal peel ply composed of resin-impregnated fabric. After surface preparation, the composite substrate is provided with a chemically-active, bondable surface that can be adhesively bonded to another composite substrate to form a covalently-bonded structure.

An adhesion improver for amine curing epoxy resin paint which, when added in a small amount to amine curing epoxy resin paint, is capable of preventing the inhibition of adhesion caused by amine blushing and of giving good interlayer adhesion is provided. This adhesion improver is a composition which contains a polymer obtained by the polymerization of (A) acrylic acid ester and/or methacrylic acid ester which has a formula as follows: ##STR00001##
wherein R.sub.1 denotes a hydrogen atom or a methyl group, and R.sub.2 denotes a branched alkyl group having 3 to 18 carbon atoms, and (B) acrylic acid ester other than (A) above and/or methacrylic acid ester other than (A) above and/or vinyl ether.

An adhesion improver for amine curing epoxy resin paint which, when added in a small amount to amine curing epoxy resin paint, is capable of preventing the inhibition of adhesion caused by amine blushing and of giving good interlayer adhesion is provided. This adhesion improver is a composition which contains a polymer obtained by the polymerization of (A) acrylic acid ester and/or methacrylic acid ester which has a formula as follows: ##STR00001##
wherein R.sub.1 denotes a hydrogen atom or a methyl group, and R.sub.2 denotes a branched alkyl group having 3 to 18 carbon atoms, and (B) acrylic acid ester other than (A) above and/or methacrylic acid ester other than (A) above and/or vinyl ether.