from a group consisting of pressure speed and mass of the scratch off toner it is understood that the logic and control unit 14 controls the pressure speed and mass of the scratch off toner 40 that is applied by the scratch off document apparatus 9 to achieve the desired sintering as understood by those skilled in the art the pressure speed and mass of the scratch off toner 40 can be applied individually or in any combination to achieve the desired level of sintering it can also be advantageous to raise the temperature during the sintering process to help with the sintering but care must be taken to ensure that increased temperature should not cause a heat softening or a melt process in which the materials undergoes a phase transition the scratch off toner 40 preferably has properties that permit it to scratch off optimally in this regard the scratch off toner 40 includes particles at least 10 microns larger than the underlying image toner 20 the scratch off toner 40 also has a molecular weight of between 2 000 and 100 000 and a glass transition temperature tg between 50 degrees celsius and 80 degrees celsius the scratch off toner 40 can also be heated up to a temperature less than 10 degrees below the glass transition temperature during sintering in another embodiment the scratch off toner 40 further includes a semi crystalline additive which has a melt temperature.