Polypropylene articles peroxidized and grafted with acidic or basic unsaturated monomers and the production of said articles

Claim 1

IN A PROCESS FOR RENDERING MANUFACTURED SHAPED ARTICLES COMPRISED OF POLYPROPYLENE CONSISTING AT LEAST PREVAILINGLY OF ISOTACTIC MACROMOLECULES RECEPTIVE TO A DYE SELECTED FROM THE GROUP CONSISTING OF ACID DYES AND BASIC DYES, WITHOUT ANY SUBSTANTIAL CHANGE IN THE MECHANICAL PROPERTIES OF THE ARTICLES, WHICH PROCESS COMPRISES PEROXIDIZING THE POLYPROPYLENE SUBSTANTIALLY EXCLUSIVELY AT THE SURFACE OF THE ARTICLE BY DIPPING THE ARTICLE IN A GASEOUS MEDIUM CONTAINING FROM 10% TO 100% OF OXYGEN, AT A PRESSURE OF FROM 1 TO 10 ATMOSPHERES, AND AT A TEMPERATURE ABOVE 50*C., UNTIL ABOUT 0.01 TO ABOUT 1.0% OF OXYGEN BY WEIGHT IS INTRODUCED INTO THE POLYPROPYLENE IN THE FORM OF HYDROPEROXIDE GROUPS, THE IMPROVEMENT BEING THE APPLICATION TO THE SUPERFICIALLY PEROXIDIZED ARTICLE, AT A TEMPERATURE BETWEEN 50*C. AND 100*C., AN UNSATURATED MONOMER WHICH IS SELECTED FROM THE GROUP CONSISTING OF METHACRYLIC ACID DERIVATIVES HAVING THE GENERAL FORMULA