A laminar pre-preg of fibre-reinforced curable composite material, wherein said pre-preg comprises at least one layer of reinforcing fibres impregnated with a curable resin comprising one or more multi-functional epoxy resin(s) in combination with one or more difunctional epoxy resin(s), at least one liquid curative, and dicyandiamide in solid or particulate form, wherein: (i) said multi-functional epoxy resin(s) is/are selected from resin based on glycidyl ethers of phenol and cresol epoxy novolacs, glycidyl ethers of phenol-aldehyde adducts, aromatic epoxy resins, aliphatic triglycidyl ethers, dialiphatic triglycidyl ethers, aliphatic polyglycidyl ethers, epoxidised olefins, triglycidyl aminophenols, aromatic glycidyl amines, heterocyclic glycidyl imidines and amides, glycidyl ethers, fluorinated epoxy resins, N,N,N',N'-tetraglycidyl diamino diphenylmethane (TGDDM) and N,N,N',N'-tetraglycidyl-m-xylenediamine, or any combination thereof; and wherein said difunctional epoxy resins are selected from diglycidyl ether of bisphenol F (DGEBF), diglycidyl ether of bisphenol A (DGEBA), diglycidyl ether of dihydroxy naphthalene, or any combination thereof; (ii) the at least one liquid curative is selected from substituted imidazoles, wherein the substituent groups of said substituted imidazoles are or comprise alkyl and/or aryl substituent groups, and preferably the liquid curative is selected from 1-cyanoethyl-2-ethyl-4-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-methyl imidazole, 4-methyl imidazole, 1-benzyl-2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-(3-aminopropyl)imidazole, 1,2-dimethylimidazole, 1-cyanoethyl-2-undecylimidazole, and 4,5-bis[(2-cyanoethoxy)methyl]-2-phenyl-IH-imidazole-1 -propiononitrile; (iii) said reinforcing fibres exhibit a tow size of at least 12,000 filaments per tow and said at least one layer of reinforcing fibres is a fabric which exhibits an areal weight of at least 300 g/m 2; (iv) the curable resin exhibits a cure conversion of at least 95%, preferably at least 98%, when cured at a cure temperature in the range of from about 100°C to about 160°C wherein the cure cycle has a duration of no more than 10 minutes, preferably no more than 8 minutes; and (v) the glass transition temperature (Tg) of the curable resin when cured is in the range of from 130°C to 165°C, Tg being measured as specified in the description. (i) said multi-functional epoxy resin(s) is/are selected from resin based on glycidyl ethers of phenol and cresol epoxy novolacs, glycidyl ethers of phenol-aldehyde adducts, aromatic epoxy resins, aliphatic triglycidyl ethers, dialiphatic triglycidyl ethers, aliphatic polyglycidyl ethers, epoxidised olefins, triglycidyl aminophenols, aromatic glycidyl amines, heterocyclic glycidyl imidines and amides, glycidyl ethers, fluorinated epoxy resins, N,N,N',N'-tetraglycidyl diamino diphenylmethane (TGDDM) and N,N,N',N'-tetraglycidyl-m-xylenediamine, or any combination thereof; and wherein said difunctional epoxy resins are selected from diglycidyl ether of bisphenol F (DGEBF), diglycidyl ether of bisphenol A (DGEBA), diglycidyl ether of dihydroxy naphthalene, or any combination thereof; (ii) the at least one liquid curative is selected from substituted imidazoles, wherein the substituent groups of said substituted imidazoles are or comprise alkyl and/or aryl substituent groups, and preferably the liquid curative is selected from 1-cyanoethyl-2-ethyl-4-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-methyl imidazole, 4-methyl imidazole, 1-benzyl-2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-(3-aminopropyl)imidazole, 1,2-dimethylimidazole, 1-cyanoethyl-2-undecylimidazole, and 4,5-bis[(2-cyanoethoxy)methyl]-2-phenyl-IH-imidazole-1 -propiononitrile; (iii) said reinforcing fibres exhibit a tow size of at least 12,000 filaments per tow and said at least one layer of reinforcing fibres is a fabric which exhibits an areal weight of at least 300 g/m 2; (iv) the curable resin exhibits a cure conversion of at least 95%, preferably at least 98%, when cured at a cure temperature in the range of from about 100°C to about 160°C wherein the cure cycle has a duration of no more than 10 minutes, preferably no more than 8 minutes; and (v) the glass transition temperature (Tg) of the curable resin when cured is in the range of from 130°C to 165°C, Tg being measured as specified in the description.