Nitrogen dosed base

Abstract

A container base that is capable of withstanding an internal pressure and further capable of causing an even deflection, such as that created by introducing liquefied gas during a hot filling process. The base includes a heel with a standing ring disposed at a lower portion thereon. A generally concave push up portion extends radially inward from the standing ring portion. At least two reinforcing rings are disposed on the push up portion, wherein the reinforcing rings diminish uneven deflection to prevent the container from tipping while resting on a flat surface.

1 . A plastic bottle suitable for containing a non-carbonized beverage, said bottle comprising:
 a body and a neck that terminates in a finish;   an enclosed based extending from a lower portion of the body, said base comprising:
 a heel that is curved in transverse cross section; 
 a standing ring portion disposed at a lower portion of the heel, the standing ring portion includes circumferentially spaced apart contact portions, each one of the contact portions being generally arcuate in transverse cross, the bottle resting on the contact portion while upright; 
 a generally concave push-up portion extending radially inwardly from the standing ring portion, the push-up portion including: (i) a gate area substantially at a center thereof, (ii) a first substantially circular reinforcing ring disposed proximate the standing ring portion, and (iii) a second substantially circular reinforcing ring disposed between the gate area and the first reinforcing ring; and 
 plural ribs extending radially outwardly from the gate portion, through the first and second reinforcing rings, and through the standing ring, 
   whereby the reinforcing rings contain deflection and diminish uneven deflection of the base in response to positive internal pressure.   
     
     
         2 . The bottle of  claim 1  wherein the base resists inversion by uniformly transmitting forces to the contact portion of the standing ring. 
     
     
         3 . The bottle of  claim 1  wherein the first reinforcing ring and the second reinforcing ring are generally concave. 
     
     
         4 . The bottle of  claim 1  wherein the gate area includes a recess in the center thereof for receiving a preform's gate during blow molding. 
     
     
         5 . The bottle of  claim 1  wherein the gate area includes a depression formed by pinning a portion of the gate area between a distal end of a stretch rod and a mold. 
     
     
         6 . The bottle of  claim 1  wherein the rib has a substantially flat trough over at least a portion of its radial length. 
     
     
         7 . The bottle of  claim 6  wherein the trough is substantially flat over most of the radial length of the rib. 
     
     
         8 . The bottle of  claim 1  wherein each surface of the standing ring is arcuate in transverse cross section. 
     
     
         9 . The bottle of  claim 1  wherein each surface of the push-up portion is arcuate in transverse cross section. 
     
     
         10 . The bottle of  claim 1  wherein the quantity of contact portions is at least six and the quantity of ribs is at least six. 
     
     
         11 . A method of filling a plastic container comprising the steps of:
 (a) providing a container that includes:
 a body and a neck that terminates in a finish; 
 an enclosed based extending from a lower portion of the body, said base comprising:
 a heel that is curved in transverse cross section; 
 a standing ring portion disposed at a lower portion of the heel, the standing ring portion includes circumferentially spaced apart contact portions, each one of the contact portions being generally arcuate in transverse cross, the bottle resting on the contact portion while upright; 
 a generally concave push-up portion extending radially inwardly from the standing ring portion, the push-up portion including: (i) a gate area substantially at a center thereof, (ii) a first substantially circular reinforcing ring disposed proximate the standing ring portion, and (iii) a second substantially circular reinforcing ring disposed between the gate area and the first reinforcing ring; and 
 plural ribs extending radially outwardly from the gate portion, through the first and second reinforcing rings, and through the standing ring; 
 
   (b) introducing a liquid into the container;   (c) introducing a liquefied gas into the container; and   (d) capping or sealing the container after the introducing steps (b) and (c);   whereby the reinforcing rings contain deflection and diminish uneven deflection of the base in response to positive internal pressure.   
     
     
         12 . The method of  claim 11  wherein the step of introducing the liquid includes introducing the liquid at an elevated temperature. 
     
     
         13 . The method of  claim 11  wherein the step of introducing the liquid includes introducing the liquid approximately at ambient temperature. 
     
     
         14 . The method of  claim 11  wherein the base resists inversion by uniformly transmitting forces to the contact portion of the standing ring. 
     
     
         15 . The method of  claim 11  wherein the gate area includes a recess in the center thereof for receiving a preform's gate during blow molding. 
     
     
         16 . The method of  claim 11  wherein the gate area includes a depression formed by pinning a portion of the gate area between a distal end of a stretch rod and a mold. 
     
     
         17 . The method of  claim 11  wherein the rib has a substantially flat trough over at least a portion of its radial length. 
     
     
         18 . The method of  claim 17  wherein the trough is substantially flat over most of the radial length of the rib. 
     
     
         19 . The method of  claim 11  wherein each surface of the standing ring is arcuate in transverse cross section. 
     
     
         20 . The method of  claim 11  wherein each surface of the push-up portion is arcuate in transverse cross section.