A process for preparing a cationic latex modified hydrocarbon binder emulsion comprising the steps of: (a) preparing a cationic copolymer latex emulsion by an emulsion polymerisation of polymerizable monomers, said polymerizable monomers comprising A- one or more non-ionic acrylate ester and/or methacrylate ester monomer(s), and B- optionally styrene monomer and/or one or more non-ionic styrene derivative monomer(s), C- optionally one or more cross-linking monomer(s) having two or more ethylenically unsaturated (C=C) double bonds susceptible to free radical copolymerisation, D- optionally one or more epoxy functional monomer(s) having one C=C double bond susceptible to free radical copolymerisation and one epoxide functional group, wherein said polymerizable monomers do not comprise any aliphatic conjugated diene monomer, in presence of a cationic stabilizing surfactant, and (b) adding the cationic copolymer latex emulsion resulting from step (a) to a cationic hydrocarbon binder emulsion, or (b') adding the cationic copolymer latex emulsion resulting from step (a) to an emulsifier solution, said emulsifier solution comprising water, one or more cationic surfactant(s), one or more acid(s) and optionally additives to provide a mixture, and adding the resulting mixture to hydrocarbon binder; to form a cationic latex modified hydrocarbon binder emulsion. (a) preparing a cationic copolymer latex emulsion by an emulsion polymerisation of polymerizable monomers, said polymerizable monomers comprising A- one or more non-ionic acrylate ester and/or methacrylate ester monomer(s), and B- optionally styrene monomer and/or one or more non-ionic styrene derivative monomer(s), C- optionally one or more cross-linking monomer(s) having two or more ethylenically unsaturated (C=C) double bonds susceptible to free radical copolymerisation, D- optionally one or more epoxy functional monomer(s) having one C=C double bond susceptible to free radical copolymerisation and one epoxide functional group, wherein said polymerizable monomers do not comprise any aliphatic conjugated diene monomer, in presence of a cationic stabilizing surfactant, and A- one or more non-ionic acrylate ester and/or methacrylate ester monomer(s), and B- optionally styrene monomer and/or one or more non-ionic styrene derivative monomer(s), C- optionally one or more cross-linking monomer(s) having two or more ethylenically unsaturated (C=C) double bonds susceptible to free radical copolymerisation, D- optionally one or more epoxy functional monomer(s) having one C=C double bond susceptible to free radical copolymerisation and one epoxide functional group, wherein said polymerizable monomers do not comprise any aliphatic conjugated diene monomer, in presence of a cationic stabilizing surfactant, and (b) adding the cationic copolymer latex emulsion resulting from step (a) to a cationic hydrocarbon binder emulsion, or (b') adding the cationic copolymer latex emulsion resulting from step (a) to an emulsifier solution, said emulsifier solution comprising water, one or more cationic surfactant(s), one or more acid(s) and optionally additives to provide a mixture, and adding the resulting mixture to hydrocarbon binder; to form a cationic latex modified hydrocarbon binder emulsion.