Thermoset Resin Composite Materials Comprising Inter-Laminar Toughening Particles

A process for producing a cured composite comprising the steps of:

• (i) forming a resin composition comprising a tri-functional epoxy resin precursor and/or a tetra-functional epoxy resin precursor, one or more curing agent(s), a toughening agent selected from aromatic polvethersulphones, and polyamide particles having a melting temperature TPA,
• (ii) combining said resin composition with reinforcing fibres to form a composite material, and
• (iii) curing the composite material in a cure cycle in which a cure temperature Tc is attained with a cure ramp rate RCR in the range of 0.05° C./min to 3.0° C./min,
• wherein the cure temperature Tc is in the range of 160° C. to about 200° C., and
• wherein the gelation of the epoxy composition during the cure cycle occurs at a gelation temperature TGEL which is at or below TPA.