Hollow inflatable article

Claim 1

A HOLLOW INFLATABLE ARTICLE HAVING A WALL OF FLEXIBLE ELASTIC MATERIAL AND A SELF-SEALING INFLATION VALVE THEREIN; SAID VALVE INCLUDING A RELATIVELY RIGID ELONGATED STEM HAVING AT LEAST THE OUTER END THEREOF ANCHORED WITHIN SAID WALL, AND THE STEM HAVING AN INNER SMOOTH-SURFACE PERIPHERAL PORTION OF SUBSTANTIAL EXTENT OVER WHICH IS YIELDINGLY EXPANDED AN ELONGATED SLEEVE OF ELASTIC TUBING TO BE IN AIR-SEALING RELATION THERETO; SAID STEM HAVING AN INFLATION PASSAGE EXTENDING THERETHROUGH FOR CONNECTING THE EXTERIOR OF THE WALL WITH OUTLET MEANS AT THE INNER END OF THE PASSAGE AND INTERMEDIATE THE ENDS OF SAID SLEEVE, WHEREBY THE OUTLET MEANS IS NORMALLY AIRSEALED BY THE SLEEEVE; APPLICATION OF INFLATION AIR WITHIN THE STEM PASSAGE THEREBY BEING ADAPTED YIELDINGLY TO EXPAND SAID SLEEVE FOR PASSAGE OF INFLATION AIR PAST THE INNER END OF THE SLEEVE TO INFLATE SAID ARTICLE WALL; SAID ARTICLE WALL HAVING STRUCTURAL CHARACTERISTICS RESULTING FROM ROTATIONAL CASTING OF THERMO-PLASTIC RESIN MATERIAL IN A CLOSED MOLD WHILE IN HEAT-SOFTENED CONDITION AND BY WHICH INTEGRAL INWARD EXTENSIONS OF THE MATERIAL FROM SAID WALL WILL UPON COOLING HAVE FORMED AN ELASTIC CASING OF INWARDLY DIMINISHING THICKNESS ABOUT SAID STEM AND SLEEVE; SAID ELASTIC CASING THEREBY ANCHORING ATTACHING THE STEM TO SAID WALL AND YIELDINGLY EMBRACING THE SLEEVE IN SAID AIR-SEALING RELATIONSHIP.