CHEMICAL PRODUCTS, NAMELY, SILICIC ACIDS, SILICA AND SILANES FOR USE IN THE RUBBER, PLASTICS, AND CABLE INDUSTRIES; CHEMICAL ADDITIVES, NAMELY, SILICIC ACIDS, SILICA, AND SILANES FOR USE IN THE MANUFACTURE OF RUBBER AND PLASTIC MATERIALS, NAMELY, PLASTIC AND/OR RUBBER MIXTURES USED FOR IMPROVING THE ADHESION OF SAID MIXTURES TO TEXTILE AND METALLIC FABRICS