Abstract: The invention relates to a method of breaking a substrate of a brittle material, the method comprising the steps of providing a substrate (1) of a brittle material, heating the substrate with a laser beam (3) to create a heated spot on the substrate, moving the laser beam and the substrate with respect to each other to create a line of heated spots on the substrate (2), cooling the heated spots on the substrate by locally applying a cooling medium (4) behind the heated spots such that a micro-crack is propagated in the line of heated spots, and breaking the substrate along the line of the propagated micro-cracks by applying a mechanical force on the substrate wherein, the cooling medium comprises an aqueous surfactant solution. The surfactants will connect to the broken siloxane bonds inside the surface cracks. Then recombination and healing of the broken siloxane bonds will not occur and the required breaking load will remain constant over time.

Abstract: A shaving head comprises a cutting member a hair manipulator. The cutting member has a cutting edge which extends in a direction perpendicular to a shaving direction of the shaving head. The hair manipulator is arranged in front of the cutting edge, seen in the shaving direction, and can be driven in a direction parallel to the cutting edge. Hairs trapped by the hair manipulator are moved along the cutting edge while being cut, so that the cutting forces in the shaving direction are reduced. The cutting member can also be driven in a direction parallel to the cutting edge such that, seen in this direction, the cutting member and the hair manipulator move in opposite directions for a longer period of time than in equal directions. In this manner the cutting member has a stretching effect on the skin present immediately in front of the cutting edge, and said stretching effect of the cutting member intensifies a similar stretching effect of the hair manipulator.

Abstract: The invention relates to a shaving head (5) comprising a cutting member (17) and a hair manipulator (23). The cutting member comprises a cutting edge (19) which extends in a direction (X) perpendicular to a shaving direction (Y) of the shaving head. The hair manipulator is arranged in front of the cutting edge, seen in the shaving direction, and can be driven in a direction parallel to the cutting edge. Hairs trapped by the hair manipulator are moved along the cutting edge while being cut, so that the cutting forces in the shaving direction are reduced.