A resin composition is provided, which includes an oligomer formed by reacting bisphenol epoxy resin monomer, aliphatic diglycidyl ether, anhydride compound, and catalyst, wherein the molar ratio of epoxy groups of the bisphenol epoxy resin monomer and aliphatic diglycidyl ether to anhydride groups of the anhydride compound is between 3.5:1 and 8.8:1. The bisphenol epoxy resin monomer and aliphatic diglycidyl ether have a molar ratio of 0.3:1 to 1.3:1, and the viscosity of the resin composition is 20 Pa.Math.s to 80 Pa.Math.s at 25 C.

The present invention provides an epoxy resin composition that can produce a cured product maintaining good dielectric characteristics (low dielectric constant and low dielectric loss tangent), and having high adhesion strength to metal; and also provides a process for producing the same, a cured product obtained by curing the epoxy resin composition, and use thereof. The present invention includes an epoxy resin composition comprising an epoxy resin, an acid anhydride-based curing agent, and a curing accelerator, the epoxy resin being represented by the formula (1):

##STR00001##

wherein X is a divalent group obtained by removing two hydrogen atoms from a hydrocarbon ring, or a divalent group represented by the formula (2):

##STR00002##

wherein Y is a bond, a C.sub.1-6 alkylene group, etc.;

R.sup.1 is the same or different, and is a C.sub.1-18 alkyl group, etc.,

R.sup.2 is the same or different, and is a C.sub.1-18 alkylene group, etc.,

R.sup.3 is the same or different, and is a C.sub.1-18 alkyl group, etc., and

n is the same or different, and is an integer of 0 to 3. The present invention also includes a process for producing the same, a cured product of the epoxy resin composition, and use thereof.

A hardener composition for epoxy resins includes a dianhydride and one or both of a monoanhydride and a hydroxyl-diterminated poly(phenylene ether). The hardener components can be blended in the substantial absence of solvent to yield a homogeneous composition having a reduced glass transition temperature or melting point that facilitates reduced-temperature blending of the hardener composition with the epoxy resin.

Provided are an epoxy resin composition and a prepreg, laminated board and printed-circuit board comprising same. The epoxy resin composition comprises the following components: (A) 38-54 parts by weight of an epoxy resin comprising a DCPD structure; (B) 30-36 parts by weight of an active ester curing agent; and (C) 16-32 parts by weight of a cyanate resin, With the mutual cooperation and synergistic facilitation effects of the particular contents of the three essential components, the epoxy resin composition is obtained. Under the premise of having a high resistance to heat and humidity and a high heat resistance at the same time, the prepreg, laminated board and printed-circuit board made of the epoxy resin composition further have a low thermal expansion coefficient, a low water absorption rate and excellent dielectric properties.

The image display device sealing material contains a resin component and a curing agent, wherein the resin component contains biphenyl skeleton-containing epoxy resin having a weight-average molecular weight of 200 or more and 100,000 or less, alicyclic skeleton-containing epoxy resin having a weight-average molecular weight of 180 or more and 790 or less, and styrene oligomer having a weight-average molecular weight of 750 or more and 4000 or less.

A resin composition is provided, which includes an oligomer formed by reacting bisphenol epoxy resin monomer, aliphatic diglycidyl ether, anhydride compound, and catalyst, wherein the molar ratio of epoxy groups of the bisphenol epoxy resin monomer and aliphatic diglycidyl ether to anhydride groups of the anhydride compound is between 3.5:1 and 8.8:1. The bisphenol epoxy resin monomer and aliphatic diglycidyl ether have a molar ratio of 0.3:1 to 1.3:1, and the viscosity of the resin composition is 20 Pa.Math.s to 80 Pa.Math.s at 25 C.

Disclosed are compositions relating to optically clear epoxy resin formulations with filler compositions having superior regular transmission of light between 350 nm and 2500 nm, and a low coefficient of thermal expansion, along with optoelectronic devices sealed with the same.

A curing agent composition comprising anhydride and approximately equimolar amount of tertiary amine or imidazole and carboxylic acid, the amine being 1-piperidinylethanol (N-hydroxyethyl-piperidine, NHEP) represented by the structure below or an imidazole represented by the structure below:

##STR00001##

where R.sub.1=H, a C1-C20 straight chain or branched alkyl, or a monocyclic aryl; R.sub.2=a C1-C20 straight chain or branched alkyl, or a monocyclic aryl. The carboxylic acid is represented by RCOOH; R=a C1-C20 straight chain or branched alkyl, or a monocyclic aryl. The composition comprises a lower ratio of epoxy resin to anhydride (1:0.4-0.6) than typically used (1:0.8-1.1). In addition, it uses a higher loading of the hindered latent tertiary amine or the imidazole in combination with the carboxylic acid (wt % ratio of combined amine and carboxylic acid to anhydride 10%). With this composition a full cure can be achieved in less than 2 hr at a significantly lower temperature (100 C.).

Provided is a sheet-like prepreg that has both a low coefficient of linear thermal expansion and high flexibility and offers excellent anti-warpage performance and cracking resistance. The sheet-like prepreg according to the present invention includes a curable composition and a sheet-like porous support impregnated with the curable composition. The sheet-like porous support is made from a material having a coefficient of linear thermal expansion of 10 ppm/K or less. The sheet-like prepreg gives a cured product having a glass transition temperature of 60 C. to 100 C. The curable composition includes one or more curable compounds (A) and at least one of a curing agent (B) and a curing catalyst (C). The curable compounds (A) include an epoxide having a weight per epoxy equivalent of 140 to 3000 g/eq in an amount of 50 weight percent or more of the totality of the curable compounds (A).

The present invention relates to a curable two-part resin system having a resin part containing at least one cycloaliphatic epoxy resin and a hardener part containing (i) at least one alicyclic anhydride, and (ii) a block-copolymer having polysiloxane blocks and organic blocks, and containing greater than 60 wt % of an inorganic filler.