Thermosetting resin composition and prepreg and laminate obtained with the same

A thermosetting resin composition comprising:

• (A) a curing agent having an acidic substituent and an unsaturated maleimide group which is produced by reacting (a-1) a maleimide compound having at least two N-substituted maleimide groups in a molecule with (a-2) an amine compound having an acidic substituent represented by the following Formula (1) in an organic solvent,
• (B) a 6-substituted guanamine compound represented by the following Formula (2) and/or dicyandiamide,
• (C) a copolymer resin comprising (c-1) a monomer unit represented by the following Formula (3) and (c-2) a monomer unit represented by the following Formula (4) and
• (D) an epoxy resin having at least two epoxy groups in a molecule:
• (wherein R1 each represents independently an acidic substituent selected from a hydroxyl group, a carboxy group and a sulfonic acid group;
• R2 each represents independently a hydrogen atom, an aliphatic hydrocarbon group having 1 to 5 carbon atoms or a halogen atom;
• x is an integer of 1 to 5, and y is an integer of 0 to 4;
• and a sum of x and y is 5);
• (wherein R3 represents phenyl, methyl, allyl, butyl, methoxy or benzyloxy);
• (wherein R4 and R5 each represent independently a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 5 carbon atoms, a phenyl group or a substituted phenyl group);