A resin composition including a polyester polyurethane resin (A); and an epoxy resin (B), in which a molecular weight per a urethane bond of the polyester polyurethane resin (A) is from 200 to 8,000, and a layered body including a resin composition layer, a layered body, a flexible copper-clad laminate, a flexible flat cable, or an electromagnetic wave shielding film, each using the resin composition.

A resin composition including a polyester polyurethane resin (A); and an epoxy resin (B), in which a molecular weight per a urethane bond of the polyester polyurethane resin (A) is from 200 to 8,000, and a layered body including a resin composition layer, a layered body, a flexible copper-clad laminate, a flexible flat cable, or an electromagnetic wave shielding film, each using the resin composition.

An epoxy resin mixture which contains an epoxy resin represented by Formula (1) below and an epoxy resin represented by Formula (2) below at a weight ratio of 1:5 to 1:0.2. (In Formula (1), plural R1's each exist independently and represent a hydrogen atom or a C1-10 alkyl group, n represent a real number of 1 to 10, and G represents a substituted or unsubstituted glycidyl group.) (In Formula (2), plural R2's and R3's each exist independently and represent a hydrogen atom or a C1-10 alkyl group, n represents a real number of 1 to 10, and G represents a substituted or unsubstituted glycidyl group.)

##STR00001##

An epoxy resin mixture which contains an epoxy resin represented by Formula (1) below and an epoxy resin represented by Formula (2) below at a weight ratio of 1:5 to 1:0.2. (In Formula (1), plural R1's each exist independently and represent a hydrogen atom or a C1-10 alkyl group, n represent a real number of 1 to 10, and G represents a substituted or unsubstituted glycidyl group.) (In Formula (2), plural R2's and R3's each exist independently and represent a hydrogen atom or a C1-10 alkyl group, n represents a real number of 1 to 10, and G represents a substituted or unsubstituted glycidyl group.)

##STR00001##

A thermosetting resin composition and a prepreg are provided. The thermosetting resin composition includes a maleimide resin, a cyanate ester resin, and a crosslinking agent. The crosslinking agent is a silane-modified diallyl bisphenol compound whose structure is represented by Formula (1):

##STR00001##

In Formula (1), X is a linear or branched C1 to C6 alkyl, cycloalkyl, or sulfonyl group, R1 is a linear or branched C1 to C6 alkyl or aryl group, R2 is a C1 to C6 alkyl group, R3 is a functional group with a crosslinkable double bond, and n+m is a positive integer from 1 to 8.

A thermosetting resin composition and a prepreg are provided. The thermosetting resin composition includes a maleimide resin, a cyanate ester resin, and a crosslinking agent. The crosslinking agent is a silane-modified diallyl bisphenol compound whose structure is represented by Formula (1):

##STR00001##

In Formula (1), X is a linear or branched C1 to C6 alkyl, cycloalkyl, or sulfonyl group, R1 is a linear or branched C1 to C6 alkyl or aryl group, R2 is a C1 to C6 alkyl group, R3 is a functional group with a crosslinkable double bond, and n+m is a positive integer from 1 to 8.

Disclosed is a curable composition comprising an elastomer (A), an epoxy resin (B) and a latent curing agent (C), wherein the latent curing agent (C) comprises a combination of two or more latent curing agents.

Disclosed is a curable composition comprising an elastomer (A), an epoxy resin (B) and a latent curing agent (C), wherein the latent curing agent (C) comprises a combination of two or more latent curing agents.

An epoxy-functionalized polyorganosiloxane toughener providing toughening properties for thermosetting resins is described. The epoxy-functionalized polyorganosiloxane toughener is an epoxy-functionalized siloxane polyether with a siloxane backbone, at least one epoxy-containing alkyl chain, and at least one alkoxyl polyether chain, each said at least one epoxy-containing alkyl chain and at least one alkoxyl polyether chain grafted to the siloxane backbone. Also disclosed is a thermosetting resin-based composition comprising the epoxy-functionalized polyorganosiloxane toughener of claim 1 and at least one of an epoxy resin, a hardener, and an accelerator.

An epoxy-functionalized polyorganosiloxane toughener providing toughening properties for thermosetting resins is described. The epoxy-functionalized polyorganosiloxane toughener is an epoxy-functionalized siloxane polyether with a siloxane backbone, at least one epoxy-containing alkyl chain, and at least one alkoxyl polyether chain, each said at least one epoxy-containing alkyl chain and at least one alkoxyl polyether chain grafted to the siloxane backbone. Also disclosed is a thermosetting resin-based composition comprising the epoxy-functionalized polyorganosiloxane toughener of claim 1 and at least one of an epoxy resin, a hardener, and an accelerator.