A resin composition and uses thereof are provided. The resin composition includes: (A) a polyfunctional vinyl aromatic copolymer; and (B) a compound having a structure of formula (I), ##STR00001## wherein the polyfunctional vinyl aromatic copolymer (A) is prepared by copolymerizing one or more divinyl aromatic compounds with one or more monovinyl aromatic compounds, and in formula (I), Y.sub.1 is an organic group.

Manufacturing method includes forming photoresist layer including photoresist composition over substrate. Photoresist composition includes: photoactive compound, polymer, crosslinker. The polymer structure ##STR00001##
A1, A2, A3 independently C1-C30 aryl, alkyl, cycloalkyl, hydroxylalkyl, alkoxy, alkoxyl alkyl, acetyl, acetylalkyl, carboxyl, alky carboxyl, cycloalkyl carboxyl, hydrocarbon ring, heterocyclic, chain, ring, 3-D structure; R1 is C4-C15 chain, cyclic, 3-D structure alkyl, cycloalkyl, hydroxylalkyl, alkoxy, or alkoxyl alkyl; proportion of x, y, and z in polymer is 0x/(x+y+z)1, 0y/(x+y+z)1, and 0z/(x+y+z)1, x, y, and z all not 0 for same polymer. Crosslinker is monomer, oligomer, polymer including structures ##STR00002##
B1, B2, B3, B4, and D each independently C1-C30 aryl, alkyl, cycloalkyl, hydroxylalkyl, alkoxy, alkoxyl alkyl, acetyl, acetylalkyl, carboxyl, alky carboxyl, cycloalkyl carboxyl, hydrocarbon ring, heterocyclic group, chain, ring, 3-D structure; R2 and Ra are C4-C15 chain, cyclic, 3-D structure alkyl, cycloalkyl, hydroxylalkyl, alkoxy, alkoxyl alkyl.

This disclosure relates to a film layer for use in flexible metal clad laminates. The film layer comprises a thermosetting composition comprising: a copolymer of (a) a diisoalkenylarene (DIAEA) and (b) a divinylarene (DVA) containing a mixture of m-divinylarene and p-divinylarene, in a mole ratio of (a) to (b) of 15:1 to 1:15; a second polymer; a filler and optional additives. Flexible metal clad laminates made with the film further comprises a metal foil bonded to the surface of the film. The thermosetting composition containing the DIAEA-DVA copolymer provides improved thermal stability at high temperature, excellent processability, and electrical properties, e.g., Dk and Df.