Brush intended for the application of a cosmetic product, in particular to the eyelashes or the hair

Brush intended for the application of a cosmetic product, comprising a plurality of bristles transversely implanted in an elongated core formed by turns of a twisted metal wire, said bristles being wedged between said turns, said bristles comprising bristles selected from at least two groups, namely a first group including bristles of relatively small cross-section, lieing in a circle having a diameter of between 6 and 13 hundredths of a millimeter, and a second group of bristles of larger cross-section lieing in a circle having a diameter larger than 13 hundredths of a millimeter and generally smaller than 30 hundredths of a millimeter, said bristles of each group extending in a radial direction relative to said core, the bristles of small cross-section having a greater length in the radial direction than the bristles of large cross-section, over at least part of the brush, characterised in that the bristles of small cross-section are made of a thermoplastic having a higher melting point than the melting point of a thermoplastic elastomer from which the bristles of large cross-section are made, the melting point of a thermoplastic of the bristles of small section being of the order of 230.degree. to 280.degree. C., while the melting point of the thermoplastic elastomer of the bristles of larger cross-section is of the order of 150.degree. to 230.degree. C.