A semiconductor composition which comprises a soluble polyacene semiconductor and a polymeric semiconducting binder, the polymeric semiconducting binder having a permittivity greater than 3.4 at 1000 Hz and wherein the polymeric semiconducting binder comprises a homopolymer or copolymer of one of the following formulae: wherein R x is independently hydrogen, an alkyl group, an alkoxy group, halogen, a nitro group or R y, where each R y is independently a cyano group or an organic group that includes at least one CN group, with the proviso that at least one repeat unit in the triarylamine polymer includes an R y group and that the sum of indices (j+k+l) is at least 1, sufficient R y groups being present in the polymer to ensure that its permittivity is greater than 3.4 at 1000 Hz and which R x groups may not be the same in all of the repeat units of the first part of the above formula, R z is independently in each occurrence an alkyl group and is intended to include not only pure open chain saturated hydrocarbon alkyl substituents but also alkyl substituents bearing further substituents selected from hydroxyl, alkoxy, alkylsulphonyl, halogen, cyano, nitro, amino and carboxyl, different selections from the alternatives within the definitions of R x and R y may be made in different units of the polymer, A is independently in each occurrence hydrogen, halogen or any suitable end-capping group; j and I are independently in each occurrence 0 to 4; k is independently in each occurrence 0 to 5; a is the number of monomer units of Formula (shown on the left of the formula of this claim) in the polytriarylamine compound, and the polymer comprises between 5 and 100% of monomer of Formula, b is the number of monomer units of monomer of Formula in the polytriarylamine compound (shown on the right of the formula of this claim), in some cases b will equal 0, and R a and R b each independently represent hydrogen, a substituted or unsubstituted aromatic hydrocarbon cyclic group having 6 to 50 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 50 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 50 atoms, a substituted or unsubstituted aralkyl group having 6 to 50 carbon atoms, a substituted or unsubstituted aryloxy group having 5 to 50 carbon atoms, a substituted or unsubstituted arylthio group having 5 to 50 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 1 to 50 carbon atoms, a substituted or unsubstituted silyl group having 1 to 50 carbon atoms, acarboxy group, a halogen atom, a cyano group, nitro or hydroxyl group. wherein R x is independently hydrogen, an alkyl group, an alkoxy group, halogen, a nitro group or R y, where each R y is independently a cyano group or an organic group that includes at least one CN group, with the proviso that at least one repeat unit in the triarylamine polymer includes an R y group and that the sum of indices (j+k+l) is at least 1, sufficient R y groups being present in the polymer to ensure that its permittivity is greater than 3.4 at 1000 Hz and which R x groups may not be the same in all of the repeat units of the first part of the above formula, R z is independently in each occurrence an alkyl group and is intended to include not only pure open chain saturated hydrocarbon alkyl substituents but also alkyl substituents bearing further substituents selected from hydroxyl, alkoxy, alkylsulphonyl, halogen, cyano, nitro, amino and carboxyl, different selections from the alternatives within the definitions of R x and R y may be made in different units of the polymer, A is independently in each occurrence hydrogen, halogen or any suitable end-capping group; j and I are independently in each occurrence 0 to 4; k is independently in each occurrence 0 to 5; a is the number of monomer units of Formula (shown on the left of the formula of this claim) in the polytriarylamine compound, and the polymer comprises between 5 and 100% of monomer of Formula, b is the number of monomer units of monomer of Formula in the polytriarylamine compound (shown on the right of the formula of this claim), in some cases b will equal 0, and R a and R b each independently represent hydrogen, a substituted or unsubstituted aromatic hydrocarbon cyclic group having 6 to 50 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 50 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 50 atoms, a substituted or unsubstituted aralkyl group having 6 to 50 carbon atoms, a substituted or unsubstituted aryloxy group having 5 to 50 carbon atoms, a substituted or unsubstituted arylthio group having 5 to 50 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 1 to 50 carbon atoms, a substituted or unsubstituted silyl group having 1 to 50 carbon atoms, acarboxy group, a halogen atom, a cyano group, nitro or hydroxyl group.