Capsule for preparing infusion beverages or soluble substances in particular coffee or chocolate milk, comprising a containing body having a base, said containing body comprising at least one internal volume containing at least one substance to be infused or melted, said base being equipped with an outlet nozzle of said infusion beverage or soluble substance from said internal volume and at least one portion of an internal surface of said base being covered by at least one insulating layer separating said internal volume of said containing body from said nozzle, said insulating layer being arranged on said base stretched above at least one recess of said surface, said recess being fluid communicating with said nozzle, said insulating layer being an aluminum foil adapted to be broken through in correspondence with at least one recess under an action of a pressure increase inside said internal volume of said containing body, to create, in correspondence with at least one recess, at least one passage through said insulating layer for said infusion beverage or soluble substance from said internal volume of said containing body towards said nozzle through at least one recess, characterized in that said internal surface of said base being equipped with at least two reliefs (13', 13'') supporting said insulating layer, said reliefs (13', 13") being of a substantially circular shape and arranged concentric to said nozzle with respect to a longitudinal axis (S- S) of said base, a circular crown interposed between said reliefs (13', 13") defining at least one recess, and in that said passage between the internal volume of the containing body and the nozzle through the insulating layer is spontaneously created, without requiring opening means and in correspondence with at least one recess, only by the pressure increase exerted by the infusion beverage or soluble substance which is created inside the volume. a containing body having a base, said containing body comprising at least one internal volume containing at least one substance to be infused or melted, said base being equipped with an outlet nozzle of said infusion beverage or soluble substance from said internal volume and at least one portion of an internal surface of said base being covered by at least one insulating layer separating said internal volume of said containing body from said nozzle, said insulating layer being arranged on said base stretched above at least one recess of said surface, said recess being fluid communicating with said nozzle, said insulating layer being an aluminum foil adapted to be broken through in correspondence with at least one recess under an action of a pressure increase inside said internal volume of said containing body, to create, in correspondence with at least one recess, at least one passage through said insulating layer for said infusion beverage or soluble substance from said internal volume of said containing body towards said nozzle through at least one recess, characterized in that said internal surface of said base being equipped with at least two reliefs (13', 13'') supporting said insulating layer, said reliefs (13', 13") being of a substantially circular shape and arranged concentric to said nozzle with respect to a longitudinal axis (S- S) of said base, a circular crown interposed between said reliefs (13', 13") defining at least one recess, and in that said passage between the internal volume of the containing body and the nozzle through the insulating layer is spontaneously created, without requiring opening means and in correspondence with at least one recess, only by the pressure increase exerted by the infusion beverage or soluble substance which is created inside the volume.