A solventless resin composition with a low dielectric constant and a substrate structure are provided. The composition includes: (a) 20-50 parts by weight of a copolymer having the structure of Formula (I) ##STR00001## wherein, i, j, k, l, and m are independently an integer from 1 to 10; (b) 50-80 parts by weight of a compound having the structure of Formula (II) ##STR00002##
(c) 80-100 parts by weight of a hardener; and (d) 70-100 parts by weight of an inorganic filler.

Provided are a preparation method of an epoxy compound having an alkoxysilyl group in which an increase in the epoxy equivalent weight (EEW) of the epoxy compound is minimized because alkoxysilylation occurs through a simple one-step reaction using a hydroxyl group formed during the synthesis of the epoxy compound, an epoxy compound having an alkoxysilyl group prepared by the method, a composition comprising the same, and a use thereof. The method includes the reaction of an epoxy compound having a hydroxyl group with an isocyanate alkoxysilane in the presence of amine-based base catalyst, wherein the epoxy compound having an alkoxysilyl group has a mole ratio of [epoxide group]:[alkoxysilyl group] of n:1 ranging from 2:1 to 10:1, and an EEW increase of the epoxy compound having an alkoxysilyl group is less than 260/n. The epoxy compound has good physical properties when being cured.

Provided are a polyurethane-modified epoxy resin composition having satisfactory operability of processing, such as casting or impregnation, in a composition state, a production method therefor, and a composition thereof. The polyurethane-modified epoxy resin is obtained by modifying a secondary hydroxyl group-containing bisphenol-based epoxy resin (a) having an epoxy equivalent from 150 g/eq to 200 g/eq and a hydroxyl equivalent from 2,000 g/eq to 2,600 g/eq with a polyol compound (b) having an Mn of 200 or more, a polyisocyanate compound (c), and a polyol compound (d) having an Mn of less than 200 serving as a chain extender. The polyurethane-modified epoxy resin uses the epoxy resin (a) in an amount from 20 wt % to 60 wt % with respect to the total amount of the respective components (a), (b), (c), and (d), and contains a polyurethane having the epoxy resin (a) added to both terminals thereof and/or one terminal thereof.

There is provided herein a composition comprising (a) a mercapto-functional silicon compound having the general Formula (I):

##STR00001##

and a reactive resin containing at least one epoxy and/or (meth)acrylate group. There is also provided a silylated resin resulting from the reaction product of mercapto-functional silicon compound (a) and reactive resin contain at least one epoxy and/or (meth)acrylate groups.

The invention provides a resin composition comprising a specific silicone-modified epoxy resin, a specific silicone-modified phenolic resin, black pigment, and an inorganic filler. The invention also provides a resin composition comprising a specific cyanate ester compound, a specific silicone-modified epoxy resin, and a specific phenol compound and/or silicone-modified phenolic resin.

There is provided herein a composition comprising (a) a mercapto-functional silicon compound having the general Formula (I): ##STR00001##
and a reactive resin containing at least one epoxy and/or (meth)acrylate group. There is also provided a silylated resin resulting from the reaction product of mercapto-functional silicon compound (a) and reactive resin contain at least one epoxy and/or (meth)acrylate groups.

Provided are a polyurethane-modified epoxy resin composition having satisfactory operability of processing, such as casting or impregnation, in a composition state, a production method therefor, and a composition thereof. The polyurethane-modified epoxy resin is obtained by modifying a secondary hydroxyl group-containing bisphenol-based epoxy resin (a) having an epoxy equivalent of from 150 g/eq to 200 g/eq and a hydroxyl equivalent of from 2,000 g/eq to 2,600 g/eq with a medium to high molecular weight polyol compound (b) having an Mn of 200 or more, a polyisocyanate compound (c), and a low molecular weight polyol compound (d) having an Mn of less than 200 serving as a chain extender. The polyurethane-modified epoxy resin uses the epoxy resin (a) in an amount of from 20 wt % to 60 wt % with respect to the total amount of the respective components (a), (b), (c), and (d), and contains a polyurethane having the epoxy resin (a) added to each of both terminals thereof and/or one terminal thereof.

A solventless resin composition with a low dielectric constant and a substrate structure are provided. The composition includes: (a) 20-50 parts by weight of a copolymer having the structure of Formula (I)

##STR00001## wherein, i, j, k, l, and m are independently an integer from 1 to 10; (b) 50-80 parts by weight of a compound having the structure of Formula (II)

##STR00002##

(c) 80-100 parts by weight of a hardener; and (d) 70-100 parts by weight of an inorganic filler.

Provided is a liquid resin composition superior in flatness after screen printing, stability in B stage, adhesiveness to a dicing tape, dicing property and adhesion to a lead frame. The liquid resin composition comprises given amounts of (A) an epoxy resin having not less than two epoxy groups in one molecule; (B) a curing agent having not less than two groups in one molecule that are reactive with epoxy groups; (C) an acrylic resin; (D) a curing agent; (E) an inorganic filler; (F) a diluent; and (G) a dimethyl silicone.

A novolac epoxy compound having an alkoxysilyl group of which composite has low CTE and increase of glass transition temperature, and requiring no coupling agent, a production method thereof, an epoxy composition including the same and a cured article thereof, are provided. A novolac epoxy compound having an alkoxysilyl group of Formulae I-1 to I-4, a production method of the novolac epoxy compound having an alkoxysilyl group by the epoxidation, alkenylation and alkoxysilylation of a novolac epoxy compound, a production method of the novolac epoxy compound having an alkoxysilyl group by the epoxidation and alkoxysilylation of a novolac epoxy compound, an epoxy composition including the novolac epoxy compound having an alkoxysilyl group, and a cured article, are provided. The cured article, i.e., the composite of the epoxy composition has improved chemical bonding efficiency due to alkoxysilyl groups. Low CTE and high glass transition temperature are exhibited.