I have this class:

    class caracteristica_fisica(osv.osv):

        _name = 'caracteristica.fisica'

        _columns = {

                     'name': fields.char('Nombre',required=True),

          }

In product category, I have a many2one field making reference to 'caracteristica.fisica' model:

    class caracteristica_fisica(osv.osv):

        _inherit = 'product.category'

        _name = 'product.category'

        _columns = {

                       'cf1':fields.many2one('caracteristica.fisica', 'Característica física 1')

         }

Once I select this many2one field (cf1) I need this value to generate a record in 'comun.denominador' table:

    class comun_denominador(osv.osv):

        _name='comun.denominador'

        _columns = {

                          'categ_id' : fields.many2one('product.category','Categoría de Producto', select=True, ondelete='cascade'),

                          'cf1_cm': fields.related('categ_id', 'cf1', string="Característica física 1", type='char', store=True, select=True),

           }

It generates the record in 'comun.denominador', but in this format:

    caracteristica.fisica(4,)

and I need it to show the real name

How can I fix it?

Thanks in advance!