Lightweight Closure with Tamper Band

Abstract

A light weight, reinforced, molded, plastic closure is provided. The closure includes an end wall and a sidewall. A portion of the end has been substantially thinned such that the portion of the end wall is substantially thinner than other portions of the closure such as the sidewall or outer peripheral end wall area. The closure may also include interrupted threads that also contributes to the low weight of the closure.

1 . A light weight, reinforced, molded, plastic closure comprising:
 an end wall including an outer peripheral edge, an upper surface, a lower surface and a first thickness measured between the upper and lower surfaces;   a sidewall extending downward and away from the outer peripheral edge of the end wall, the sidewall including an inner surface, an outer surface and a second thickness measured between the inner and outer surfaces;   a container engagement structure extending radially inward from the inner surface of the sidewall;   a tamper-indicating band extending from a lower end of the sidewall, the tamper-indicating band having a frangible section configured to break upon opening to provide a visual indication that the closure had been opened; and   a plurality of raised ribs extending radially outward from the outer surface of the sidewall and extending along the sidewall at least a portion of the distance between the outer peripheral edge and the tamper-indicating band;   a circumferentially continuous annular wall extending downward from the lower surface of the end wall;   the end wall including an inner section having an outer peripheral edge adjacent an inner surface of the annular wall and a center portion, the outer peripheral edge of the inner section and the center portion each having a third thickness;   at least a portion of the inner section located between the center portion and the outer peripheral edge of the inner section having a thickness equal to the first thickness;   wherein the first thickness is less than the third thickness; and   wherein the first thickness is less than 75% of the second thickness.   
     
     
         2 . The closure of  claim 1 , wherein the end wall includes an outer portion located between the annular wall and the outer peripheral edge of the end wall, wherein the outer portion of the end wall has a fourth thickness, wherein the first thickness is less than 75% of the fourth thickness. 
     
     
         3 . The closure of  claim 2  wherein the container engagement structure includes a threading comprising a series of threads configured to engage cooperating threads of a container, wherein each thread of the threading includes at least one interrupt in which a section of the inner surface of the sidewall is located along the path of the thread. 
     
     
         4 . The closure of  claim 3  wherein at least 60% of the area of the lower surface of the end wall is located within the annular wall, wherein each thread of the threading includes at least three interrupts. 
     
     
         5 . The closure of  claim 2 , wherein the first thickness is less than 75% of the third thickness. 
     
     
         6 . The closure of  claim 5  wherein the first thickness is between 0.01 inches and 0.03 inches, wherein the second thickness is between 0.025 inches and 0.035 inches, wherein the fourth thickness is between 0.03 inches and 0.04 inches, and wherein the third thickness is between 0.02 inches and 0.04 inches. 
     
     
         7 . The closure of  claim 5  further comprising a series of radial ribs located along the end wall and extending radially outward from a center point of the end wall, wherein the radial ribs have a fifth thickness, wherein the first thickness is less than 75% of the fifth thickness. 
     
     
         8 . The closure of  claim 1  wherein at least 50% of the end wall has a thickness that is less than 75% of the second thickness. 
     
     
         9 . The closure of  claim 1  wherein the second thickness is measured between opposing vertical portions of the inner surface and outer surface of the sidewall at a position above the container engagement structure. 
     
     
         10 . A plastic closure, comprising:
 an end wall including an outer peripheral edge, an upper surface, a lower surface and a first thickness measured between the upper and lower surfaces;   a sidewall extending downward and away from the outer peripheral edge of the end wall, the sidewall including an inner surface and an outer surface;   a container engagement structure extending radially inward from the inner surface of the sidewall;   a tamper-indicating band extending from a lower end of the sidewall, the tamper-indicating band having a frangible section configured to break upon opening to provide a visual indication that the closure had been opened; and   a plug extending downward from the lower surface of the end wall, wherein the plug is a continuous wall located within the outer peripheral edge of the end wall;   wherein the end wall includes an inner portion located within the plug and an outer portion located between the plug and the outer peripheral edge of the end wall, the outer portion having a first peripheral edge located adjacent an outer surface of the plug and a second peripheral edge located adjacent the outer peripheral edge of the end wall;   wherein the first thickness is a thickness of the inner portion of the end wall;   wherein at least a portion of the outer portion of the end wall has a second thickness;   wherein the first thickness is less than 75% of the second thickness; and   wherein the thickness of the first peripheral edge is substantially the same as the thickness of the second peripheral edge.   
     
     
         11 . The closure of  claim 10  wherein the sidewall includes a third thickness measured between the inner and outer surfaces, wherein the first thickness is less than 75% of the third thickness. 
     
     
         12 . The closure of  claim 11  wherein the container engagement structure includes a threading comprising a series of threads configured to engage cooperating threads of a container, wherein each thread of the threading includes at least one interrupt in which a section of the inner surface of the sidewall is located along the path of the thread. 
     
     
         13 . The closure of  claim 12  wherein at least 60% of the area of the lower surface of the end wall is located within the plug, wherein each thread of the threading includes at least three interrupts. 
     
     
         14 . The closure of  claim 13  wherein the inner portion of the end wall includes a thickened region that transitions into an inner surface of the sealing ring, the thickened region concentric with the plug and with the outer peripheral edge of the end wall, wherein the thickened region has a fourth thickness, wherein the first thickness is less than 75% of the fourth thickness. 
     
     
         15 . The closure of  claim 14  further comprising a series of ribs extending radially outward from a center point of the end wall, wherein the ribs have a fifth thickness, wherein the first thickness is less than 75% of the fifth thickness. 
     
     
         16 . The closure of  claim 15  wherein at least 50% of the end wall has a thickness that is less than 75% of the second thickness. 
     
     
         17 . The closure of  claim 16  wherein the first thickness is between 0.01 inches and 0.03 inches, wherein the second thickness is between 0.025 inches and 0.035 inches, wherein the third thickness is between 0.03 inches and 0.04 inches, and wherein the fourth thickness is between 0.025 inches and 0.035 inches. 
     
     
         18 . The closure of  claim 10  wherein the second thickness is measured between opposing vertical portions of the inner surface and outer surface of the sidewall at a position above the container engagement structure. 
     
     
         19 . A molded, plastic closure comprising:
 an end wall including an outer peripheral edge, an upper surface, a lower surface and a first thickness measured between the upper and lower surfaces;   a sidewall extending downward and away from the outer peripheral edge of the end wall, the sidewall including an inner surface, an outer surface and a second thickness measured between the inner and outer surfaces;   threading comprising a series of threads configured to engage cooperating threads of a container, wherein each thread of the threading includes at least three interrupts in which a section of the inner surface of the sidewall is located along the path of the thread;   a tamper-indicating band extending from a lower end of the sidewall, the tamper-indicating band having a frangible section configured to break upon opening to provide a visual indication that the closure had been opened; and   a sealing ring extending downward from the lower surface of the end wall, wherein the sealing ring is a circumferentially continuous annular wall and is substantially concentric with the outer peripheral edge of the end wall;   wherein the end wall includes an inner portion located within the sealing ring and an outer portion located between the sealing ring and the outer peripheral edge of the end wall, the inner portion having an outer periphery extending circumferentially about and adjacent to an inner surface of the sealing ring;   wherein the first thickness is a thickness of the inner portion of the end wall;   wherein the outer portion of the end wall has a third thickness;   wherein the first thickness is less than 75% of the second thickness and less than 75% of the third thickness;   wherein at least 60% of the area of the lower surface of the end wall is located within the sealing ring; and   wherein the thickness of the closure as measured about the outer periphery of the inner portion is substantially constant about the entirety of the circumference of the outer periphery.   
     
     
         20 . The closure of  claim 19  wherein the first thickness is between 0.01 inches and 0.03 inches, wherein the second thickness is between 0.025 inches and 0.035 inches, wherein the third thickness is between 0.03 inches and 0.04 inches.