Dual material bottle cap

Abstract

A bottle cap is manufactured including a base cap and an integrally molded overlayer and gasket combination. The base cap is formed of a first material and includes at least one aperture passing through the base for the formation of the overlayer and gasket. The overlayer and gasket are formed by injecting a second material over the base cap and through the aperture. In particular, the overlayer is molded onto at least a portion of an outer surface of the base cap, while the gasket is simultaneously molded through the aperture, to form a sealing gasket on an underside of the base cap, integrally connected to the overlayer. The base cap and the gasket are constructed and arranged to cooperatively seal an opening of a fluid container.

1 . A bottle cap comprising: 
 a base cap having a top outer side, an underside, a perimeter, and a skirt wall extending downward from the perimeter having an exterior side and an interior side, and an outer surface formed by the top outer side and the exterior side of the skirt wall, the base cap formed of a first material having a first durometer, and having at least one aperture passing through the base cap between the top outer side and the underside;    an overlayer integrally molded onto at least a part of the outer surface of the base cap, the overlayer formed of a second material having a second durometer lower than the first durometer of the base cap; and    a gasket formed of the second material on the underside of the base cap simultaneously with the overlayer, and being spaced away from the interior side of the skirt wall, the gasket and the overlayer being integrally connected through the at least one aperture.    
   
   
       2 . The bottle cap of  claim 1 , wherein the first durometer is within a range of approximately 50 shore D to 80 shore D.  
   
   
       3 . The bottle cap of  claim 1 , wherein the second durometer is within a range of approximately 20 shore A to 95 shore A.  
   
   
       4 . The bottle cap of  claim 1 , wherein the gasket is an annular ring.  
   
   
       5 . The bottle cap of  claim 1 , wherein the gasket is circular.  
   
   
       6 . The bottle cap of  claim 1 , wherein the gasket has a rectangular cross section.  
   
   
       7 . The bottle cap of  claim 1 , wherein the first material is a thermoplastic, and the second material is selected from one of a thermoset elastomer, a thermoplastic elastomer, and a thermoplastic.  
   
   
       8 . The bottle cap of  claim 1 , wherein the overlayer is molded onto a part of the top outer side of the base cap.  
   
   
       9 . The bottle cap of  claim 1 , wherein the overlayer is molded onto the entire exterior side of the skirt wall.  
   
   
       10 . The bottle cap of  claim 1 , wherein the overlayer includes at least one grip enhancement.  
   
   
       11 . The bottle cap of  claim 1 , wherein the overlayer includes a plurality of circumferentially spaced apart recesses formed in the overlayer.  
   
   
       12 . The bottle cap of  claim 1 , wherein the overlayer includes a plurality of circumferentially spaced apart bumps formed on the overlayer.  
   
   
       13 . The bottle cap of  claim 1 , further comprising a tether device having a first end in the form of a circular ring adapated to interference fit to a fluid container, and a second end in the form of a cap connector adapted to snap fit to the base cap, the circular ring and the cap connector coupled to one another by a tether.  
   
   
       14 . The bottle cap of  claim 13 , wherein the base cap includes a molded depression having an upstanding perimeter lid retention wall including a retention rib extending radially outward around the top, outer surface of the lid retention wall, and wherein the cap connector includes a cap retention wall extending downward from the cap connector including a cap retention rib extending radially inward around the bottom, inner surface of the cap retention wall, the lid retention wall adapted to frictionally retain the cap retention wall.  
   
   
       15 . The bottle cap of  claim 1 , wherein the top outer side of the base cap includes an elongated neck extending upward from the top outer side bounding an opening extending through the base cap, and wherein the bottle cap further comprises a closure spout shiftable on the elongated neck between a first position wherein the closure spout closes the opening of the neck and a second position wherein the opening of the neck is open.  
   
   
       16 . The bottle cap of  claim 1 , wherein the top outer side of the base cap includes a neck extending upward from the top outer side bounding an opening extending through the base cap, and a pair of upstanding stanchions spaced away from the neck and extending upward from top outer side, and wherein the bottle cap further comprises a closure flap pivotable on the stanchions between a first position wherein the closure flap closes the opening of the neck, and a second position wherein the closure flap opens the opening of the neck.  
   
   
       17 . A container assembly comprising: 
 a bottle having an exterior wall bounding a bottle interior, an opening and a bottle neck;    a bottle cap having a base cap including a skirt wall extending downward from the base cap, an inner surface extending under the base cap and over an interior surface of the skirt wall, and an outer surface extending over the base cap and over an exterior surface of the skirt wall, the base cap formed of a first material and having at least one aperture passing through the base cap between the outer surface and the inner surface;    an overlayer integrally molded onto at least a part of the outer surface and formed of a second material; and    a gasket formed of the second material and integrally molded with the overlayer to at least a portion of the inner surface of the base cap through the at least one aperture, and spaced away from the interior surface of the skirt wall, wherein the gasket bears against a portion of the bottle to seal the opening.    
   
   
       18 . The assembly of  claim 17 , wherein the gasket and the overlayer are integrally connected through the at least one aperture  
   
   
       19 . The assembly of  claim 17 , wherein the first material has a first durometer and the second material has a second duromter lower than the first material.  
   
   
       20 . The assembly of  claim 17 , wherein the gasket is an annular ring.  
   
   
       21 . The assembly of  claim 17 , wherein the gasket is circular.  
   
   
       22 . The assembly of  claim 17 , wherein the first material is a thermoplastic, and the second material is selected from one of a thermoset elastomer, a thermoplastic elastomer, and a thermoplastic.  
   
   
       23 . The assembly of  claim 1 , wherein the overlayer includes at least one grip enhancement.  
   
   
       24 . A method of molding a bottle cap, the method comprising the steps of: 
 molding a base cap of a first material having a first durometer, the base cap including a top, a perimeter, a contiguous skirt wall extending downward from the perimeter, an outer surface extending over the top and skirt wall, an inner surface extending under the top and skirt wall, and at least one aperture extending through the base cap between the outer surface and the inner surface;    integrally molding an overlayer to at least a part of the outer surface of the base cap, the overlayer formed of a second material having a second durometer lower than the durometer of the first material; and    integrally molding a gasket to the inner surface of the base cap through the at least one aperture and simultaneously with the overlayer, the gasket extending from and bonded to at least a portion of the inner surface of the base cap and integrally connected to the overlayer through the at least one aperture.    
   
   
       25 . The method of  claim 24 , including the step of integrally molding at least one grip enhancement to the overlayer.  
   
   
       26 . The method of  claim 24 , including the step of integrally molding the gasket to the inner surface of the base cap in the shape of an annular ring.