Tear-Off Lid and Method For Its Manufacture

Abstract

The invention relates to a lid ring ( 20′ ) for production of a tear-off lid, whereby a hot-sealing coating ( 62 ) is only applied to the edge ( 68 ) of the dispensing opening ( 25 ). A material saving is thus possible relative to conventional full-surface application. A coating different from the hot-sealing coating can form the lid ring surface outside the hot-sealing coating.

1 . Tear-off lid having a lid ring ( 20 ′) with a take out opening ( 25 ) covered by a tear-off foil ( 25 ″), wherein said lid ring and said tear-off foil are releasable connected to each other with a heat sealable coating ( 62 ) along the border ( 68 ) of said take out opening by a connection area, characterized in that said lid ring is not coated or is coated with a plastic coating different from said heat sealable coating ( 62 ) outside of said border or said connection area. 
   
   
       2 . Tear-off lid according to  claim 1 , characterized in that the heat sealable plastic coating is a polypropylene coating or a coating containing polypropylene, and in particular a polypropylene containing lacquer coating. 
   
   
       3 . Tear-off lid according to  claim 1 , characterized in that the plastic coating different from the heat sealable coating is a polyethylene terephthalate coating or a coating containing polyethylene terephthalate. 
   
   
       4 . Tear-off lid according to  claim 1  characterized in that the plastic coating different than the heat sealable coating extends on one side or on both sides over the whole lid ring and therefore lies in the connection area beneath the heat sealable coating. 
   
   
       5 . Tear-off lid according to  claim 1 , characterized in that the lid ring comprises a flanged edge ( 67 ) beaded towards the take out opening ( 25 ′) and that the flange is covered by the heat sealable coating. 
   
   
       6 . Tear-off lid according to  claim 1 , characterized in that the lid ring is made of metal. 
   
   
       7 . Tear-off lid according to  claim 1 , characterized in that the lid ring or the take out opening is round or oval or rectangular or is provided with another non round shape. 
   
   
       8 . Container with a tear-off lid according to  claim 1 . 
   
   
       9 . A method for manufacturing a tear-off lid wherein a tear-off foil ( 25 ) is connected to a lid ring ( 20 ′) with a take out opening ( 25 ) by heat sealing of a heat sealable material, characterized in that the heat sealable material ( 62 ) is applied on the lid ring only to the border ( 68 ) of the take out opening ( 25 ) or in the connection area with the tear-off foil and/or that the heat sealable material ( 65 ) is applied only to the border of the tear-off foil. 
   
   
       10 . Method according to  claim 9  characterized in that the heat sealable material ( 62 ,  65 ) is applied on the starting material ( 60 ) before a forming or punching thereof. 
   
   
       11 . Method according to  claim 9  characterized in that the heat sealable material ( 62 ,  65 ) is applied after a forming of the lid blank ( 20 ) or lid ring ( 20 ′) or after a punching of the tear-off foil. 
   
   
       12 . Method according to  claim 9 , characterized in that the heat sealable material is applied in liquid form or is laid on as a solid band. 
   
   
       13 . Method according to  claim 9 , characterized in that the lid ring ( 20 ′) is provided with a flange directed upwardly and inwardly ( 67 ; retort curl) and that the heat sealable coating is applied so that the flange is at least partly covered. 
   
   
       14 . Method according to  claim 9 , characterized in that the lid ring or its starting material, respectively, is provided at least on one side and preferably on both sides with a plastic coating that is not suitable for heat sealing. 
   
   
       15 . Method according to  claim 14 , characterized in that the coating not suitable for heat sealing extends beneath the heat sealable coating ( 62 ) by applying the latter as a layer on the coating not suitable for heat sealing. 
   
   
       16 . Method according to  claim 9 , characterized in that the lids are conveyed on a linear conveying apparatus by toothed belts or by chains to the working stations and in particular to the heat sealing station, as the case may be with a preceding working station along the conveying path wherein the heat sealable coating is applied to the lid rings following each other.