Abstract: The invention relates to a process for stripping, from the surface of a support, a layer of paint which has been formed and hardened thereon, characterized by the requirement of a phase of pre-treating said support before the formation on the latter of the layer of paint to be stripped, said treatment consisting in applying on the support a covering product, selected among the following products: a pre-treatment vinyl resin paint, a polyurethane resin paint. It is also an object of the invention to provide products and compositions to be used in said process.

Abstract: A plant for the cryogenic comminuting of materials which are resilient, th or difficult to comminute at room temperature, in particular rubber and plastic material, wherein the comminuting means, the charging hopper and the feeding means for the material to be comminuted are all contained within one and the same insulated enclosure, said enclosure being in communication with the outside only over calibrated adjustable openings defining a given outflow of gas, a cryogenic liquid is introduced in the comminuting means in a quantity that is variable according to the minimum optimal temperature required in the mill for any specific comminuting operation.