Cap and closure device

Abstract

This cap has a cap body having a top plate and a cylindrical portion that drops vertically form the circumferential edge thereof. A knurl portion and a non-knurl portion are formed in the cylindrical portion so as to be arranged in the circumferential direction. A knurl portion vent hole is formed in the knurl indentation and a non-knurl portion vent hole is formed in the non-knurl portion. The non-knurl portion vent hole has a circumferential length that is longer than that of the knurl portion vent hole.

1 . A cap having a top plate and a cylindrical portion that drops vertically from a circumferential edge thereof, the cap comprising: 
 knurl portions and a non-knurl portion that are formed in the cylindrical portion arranged in a circumferential direction of the cap;    a plurality of knurl indentations formed in the knurl portion at intervals in the circumferential direction of the cap;    a knurl portion vent hole formed on at least some of the plurality of knurl indentations; and    a non-knurl portion vent hole formed in the non-knurl portion and having a circumferential length that is longer than that of the knurl portion vent hole.    
   
   
       2 . A cap according to  claim 1 , wherein 
 the non-knurl portion vent hole has a lower edge portion whose external diameter is equal to or less than the external diameter of the upper edge portion, and    the cap further comprising an enlarged diameter part that is formed below the lower edge portion of the cylindrical portion and that has an external diameter that is equal to or greater than the external diameter of the upper edge portion.    
   
   
       3 . A cap according to  claim 1 , further comprising a threaded portion that is formed in the cylindrical portion.  
   
   
       4 . A closure device comprising a container that is filled with a content and a cap according to  claim 1  coupled to an opening portion thereof.  
   
   
       5 . A closure device according to  claim 4 , wherein the content may ferment.  
   
   
       6 . A cap having a top plate and a cylindrical portion that drops vertically from a circumferential edge thereof, comprising: 
 knurl portions and a non-knurl portion that are formed in the cylindrical portion arranged in a circumferential direction of the cap;    a plurality of knurl indentations formed in the knurl portion at intervals in the circumferential direction of the cap; and    a non-knurl portion vent hole formed in the non-knurl portion and having a circumferential length that is longer than that of the knurl indentations.    
   
   
       7 . A cap according to  claim 6  wherein 
 the non-knurl portion vent hole has a lower edge portion whose external diameter is equal to or less than an external diameter of an upper edge portion; and    the cap further comprising an enlarged diameter part that is formed below the lower edge portion of the cylindrical portion and that has an external diameter that is equal to or greater than the external diameter of the upper edge portion.    
   
   
       8 . A cap according to  claim 6 , further comprising a threaded portion that is formed in the cylindrical portion.  
   
   
       9 . A closure device comprising a container that is filled with a content and a cap according to  claim 6  coupled to an opening portion thereof.  
   
   
       10 . A closure device according to  claim 9 , wherein the content may ferment.