Abstract: Use of jagged cutters for the longitudinal cutting of double-face self-adhesive tapes with PP backing provides easy hand tearability.

Abstract: A double-sided adhesive tape having a continuous series of toothed notches of about 0.3 mm to 6 mm jag height which easily transversely tearable by hand.

Abstract: A cryostatic microtome with an automatic approach of the preparation automatically stops the feed movement between the microtome knife and a frozen preparation towards each other upon a mechanical contact between the knife and the preparation. An electrical voltage of a few volts is applied between the microtome knife and the preparation. A small current which appears, due to the intrinsic conductivity of the preparation, upon mechanical contact between the preparation and the microtome knife, and a smaller voltage drop at the preparation resulting therefrom, is current amplified by means of a preamplifier connected as an impedance converter and subsequently measured. The feed movement between the preparation and the microtome knife is automatically stopped when the voltage at the amplifier output falls below a predefined threshold voltage.