Over-wrapping envelope for filter bags and method of forming a package with over-wrapping envelope

Abstract

An over-wrapping envelope containing a filter bag for an infusion product, includes a sheet of over-wrapping paper folded in a “U” shape along a transversal axis around the filter bag to have two parts of over-wrapping material superposed on said filter bag, the sheet having two parallel longitudinal flaps, a bottom flap at the folding and a top flap parallel to the bottom flap, parallel first and second closing tracks formed by grooves along lateral edges of the longitudinal flaps of the folded sheet and where the first and second tracks are obtained by mechanical deformation of the two superposed parts of the sheet (2) at the respective longitudinal flaps; and a third closing track formed by grooves along the transversal top flap obtained by mechanical deformation of the two superposed parts of the sheet at the transversal top flap.

1 . An over-wrapping envelope containing a filter bag for an infusion product, of the type such as tea in powder or leaf form, the over-wrapping envelope comprising:
 a sheet of over-wrapping material made of paper folded into a “U” shape along its transversal axis around the filter bag in such a way as to have two parts of the sheet of over-wrapping material superposed with interposed said filter bag, said sheet folded into a “U” shape having peripherally two longitudinal flaps parallel to each other, a transversal bottom flap at the folding of the “U” shape sheet and a transversal top flap parallel to the bottom flap; characterised in that it also comprises:   a first and a second closing track, parallel to each other, formed by grooves along the respective lateral edges of the two longitudinal flaps of the folded sheet, said first and second tracks being obtained by mechanical deformation of the two superposed parts of the sheet at the respective longitudinal flaps; and   a third closing track formed by grooves along the transversal top flap, said third track being obtained by mechanical deformation of the two superposed parts of the sheet at the transversal top flap.   
     
     
         2 . The envelope according to  claim 1 , wherein the first and the second closing tracks intersect the third closing track in at least one joining zone between the lateral flaps and the top flap. 
     
     
         3 . The envelope according to  claim 1 , wherein the first and second closing tracks have a respective orientation of the mechanical deformation grooves parallel to or transversal to the transversal folding axis of the envelope and wherein the third closing track has an orientation of the mechanical deformation grooves perpendicular to the orientation of the mechanical deformation grooves of the first and second closing tracks. 
     
     
         4 . The envelope according to  claim 1 , wherein the sheet of over-wrapping material is made of recycled paper. 
     
     
         5 . The envelope according to  claim 1 , comprising at least one weakening notch for opening the envelope made on the first and/or the second track and/or on the third track. 
     
     
         6 . The envelope according to  claim 1 , wherein said sheet of over-wrapping material is in direct contact with the filter bag, without any other material being interposed. 
     
     
         7 . A method for forming a package with an over-wrapping envelope of a filter bag for an infusion product, of the type such as tea in powder or leaf form, comprising the steps of:
 preparing a sheet of over-wrapping material made of paper;   folding the U-shaped sheet, along its transversal axis, about the filter bag in such a way as to have two parts of the sheet of over-wrapping material superposed with interposed said filter bag, said sheet folded in a U-shape having peripherally two longitudinal flaps parallel to each other, a transversal bottom flap at the folding of the U-shaped sheet and a transversal top flap parallel to the bottom flap;   making a first and a second closing track, parallel to each other, forming grooves along the respective lateral edges of the two longitudinal flaps of the folded sheet, said first and second tracks being obtained by mechanical deformation of the two superposed parts of the sheet at the respective longitudinal flaps;   making a third closing track formed by grooves along the transversal top flap, said third track being obtained by mechanical deformation of the two superposed parts of the sheet at the transversal top flap.   
     
     
         8 . The method according to  claim 7 , wherein the step of making the first and second tracks, and the step of making the third track occur in terms of time in two separate moments. 
     
     
         9 . The method according to  claim 7 , wherein the step of making the first and second tracks, and the step of making the third track occur simultaneously. 
     
     
         10 . The method according to  claim 7 , wherein the step of making the first and second closing tracks is obtained with a mechanical deformation configured for making repeated grooves having an orientation parallel to or transversal to the transversal axis and wherein the step of making the third closing track is obtained with a mechanical deformation configured for making repeated grooves having an orientation transversal to or parallel to the orientation of the grooves of the first and second tracks. 
     
     
         11 . The method according to  claim 7 , wherein the step of making the first and second closing tracks comprises the formation of the grooves along the entire respective lateral edge of the two longitudinal flaps of the folded sheet, until striking the top flap, and wherein the step of making the third closing track comprises the formation of the grooves along the entire top flap until striking the longitudinal flaps, in such a way that the first and the second closing tracks intersect the third closing track in at least one respective joining zone between the longitudinal flaps and the top flap. 
     
     
         12 . The method according to  claim 7 , wherein said sheet of over-wrapping material is wrapped around the filter bag without any interposing of other material, in such a way as to be directly in contact with it.