Method of producing metal packages

Abstract

A method for producing metal packages is disclosed, comprising the steps of forming a metal package, in particular from steel or aluminum, from a sheet metal material, in particular from thin or very thin sheet or tin plate, wherein the metal package comprises a cavity having inner surfaces that are coated with a paraffin-based coating material. The coating material is preferably heated after coating to a temperature above the solidifying temperature.

1 . A method of producing a metal package, comprising the steps of:
 providing a metal package made of sheet metal and having a cavity formed by inner surfaces;   providing a paraffin-based coating material;   heating said coating material to a temperature above a solidifying temperature thereof;   applying said coating material under pressure by airless spraying onto said inner surfaces of said cavity;   solidifying said coating material;   re-heating said metal package to a temperature above said solidifying temperature of said coating material; and   cooling said metal package to room temperature;   wherein said metal package is pivoted at least during said step of applying said coating material or said step of re-heating said metal package.   
     
     
         2 . The method of  claim 1 , wherein said paraffin-based coating material comprises at least 85% of paraffin. 
     
     
         3 . The method of  claim 1 , wherein said paraffin-based coating material comprises at least 95% of paraffin. 
     
     
         4 . The method of  claim 1 , wherein said metal package is made from a material selected from the group consisting of steel sheet metal and tin plate metal. 
     
     
         5 . The method of  claim 1 , wherein said container after said application step is turned upside down for pouring out excess coating material by gravity assistance. 
     
     
         6 . The method of  claim 1 , wherein a coating material is used having a solidifying temperature of more than 90° C. 
     
     
         7 . The method of  claim 1 , wherein said step of providing a metal package further comprises at least one seaming step for forming a folded seam connection, wherein said folded seam connection is completely coated with said coating material during a subsequent step of applying said coating material onto said inner surfaces of said cavity. 
     
     
         8 . The method of  claim 1 , wherein said inner surfaces of said cavity are fully wetted at least during one step selected form said step of applying said coating material and said step of re-heating said coating material. 
     
     
         9 . The method of any of  claim 1 , wherein said coating material, before being applied onto said inner surfaces of said cavity, is mixed with a solvent for paraffin. 
     
     
         10 . A method of producing a metal package, comprising the steps of:
 providing a metal package made of sheet metal and having a cavity formed by inner surfaces;   providing a paraffin-based coating material;   heating said coating material to a temperature above a solidifying temperature thereof;   applying said coating material onto said inner surfaces of said cavity;   solidifying said coating material; and   cooling said metal package to room temperature.   
     
     
         11 . The method of  claim 10 , wherein said coating material is applied under pressure. 
     
     
         12 . The method of  claim 11 , wherein said coating material is applied by an airless spraying method. 
     
     
         13 . The method of  claim 10 , wherein said coating material is applied by means of pouring or sprinkling. 
     
     
         14 . The method of  claim 10 , further comprising the step of pivoting said metal package during said step of applying said coating material. 
     
     
         15 . The method of  claim 10 , further comprising the step of pivoting said metal package during said step of re-heating said coating material. 
     
     
         16 . The method of  claim 10 , wherein said step of providing a metal package further comprises at least one seaming step for forming a folded seam connection, wherein said folded seam connection is coated with said coating material during a subsequent step of applying said coating material onto said inner surfaces of said cavity. 
     
     
         17 . The method of any of  claim 10 , wherein said coating material is mixed with a solvent for paraffin. 
     
     
         18 . The method of  claim 10 , wherein said container after said application step is turned upside down for pouring out excess coating material by gravity assistance. 
     
     
         19 . A metal package of a sheet metal material comprising a cavity having inner surfaces which are completely covered by a paraffin-based coating material. 
     
     
         20 . The metal package of  claim 19 , in which said inner surfaces comprise a shell element and at least one bottom or lid element, wherein at least said bottom element or lid element is connected to said shell element by a folded seam connection which is covered by said paraffin-based coating material.