Method for the preparation of film webs

Abstract

A device and a process for the preparation of sheets ( 7, 17 ) are specified. The following work steps are involved in the preparation of the sheets: extruding a film tube ( 1 ) laying the film tube flat and squeezing it ( 1 ) reversing the film tube ( 1 ) cutting the extruded film tube ( 1 ) In addition the invention contains following new characteristics: the film tube ( 1 ) is cut before the squeezing follows and at least one resulting sheet ( 7, 17 ) runs through ( 1 ) only one reversing device ( 100 ) before it is fed to a stationary processing device or storage device.

1 . Process for the preparation of sheets ( 7 ,  17 ) that contains the following characteristics of the process: 
 extruding a film tube ( 1 )    laying the film tube flat and squeezing it    reversing the film tube    cutting the extruded film tube ( 1 ) characterized by the fact    that the film tube is cut in the conveying direction of the film tube (z) before the squeezing ( 3 ) takes place and    that at least one resulting sheet ( 1 ) runs through only one reversing device ( 100 ) before it is fed to a stationary further processing device or storage device.    
     
     
         2 . Process in accordance with  claim 1  characterized by the fact that parts of the surfaces of at least one sheet ( 7 ,  17 ) come into contact during the reversing process.  
     
     
         3 . Process in accordance with  claim 2  characterized by the fact that the surfaces that come into contact with each other are components of the tubular sheet ( 7 ,  17 ) that formed the interior surfaces of the film tube ( 1 ).  
     
     
         4 . Process in accordance with  claim 1  characterized by the fact that sheets ( 7 ,  17 ) are prepared with at least one sticky surface in that a film tube ( 1 ) is processed with at least one sticky peripheral surface.  
     
     
         5 . Process in accordance with  claim 3  characterized by the fact that a film tube ( 1 ) is processed that has a sticky external surface and that while reversing only those surfaces of the cut film tubes ( 1 ) come into contact that had formed the internal surface of the film tube ( 1 ) before.  
     
     
         6 . Process for the preparation of sheets ( 7 ,  17 ) that contains the following characteristics: 
 a means for the extrusion of a film tube ( 1 )    a flattening device ( 2 ) and a squeezing device ( 3 ) for the film tube ( 1 )    a means ( 100 ) for the reversing of the film tube ( 1 )    at least one cut-off device ( 4 ) for slitting the extruded film tube ( 1 ) lengthwise characterized by the fact 
 that at least one cut-off device ( 4 ) is provided for slitting the extruded film tube ( 1 ) lengthwise in the conveying direction (z) of the film tube before the squeezing device ( 3 )  
 that only one reverse device ( 100 ) is provided through which at least one resulting sheet ( 7 ,  17 ) runs before it ( 7 ,  17 ) is fed to a stationary processing device or storage device.  
   
     
     
         7 . Process in accordance with the aforesaid claim characterized by a reversing device ( 100 ) whereby the sheets ( 7 ,  17 ) can be led past at least one reversing air turning bar ( 103 ,  105 ) and at least one reversing deflecting roller ( 102 ,  104 ).  
     
     
         8 . Device in accordance with the aforesaid claim characterized by the fact that the reversing device ( 100 ) contains at least one functional pair formed of an air turning bar ( 103 ,  105 ) and a deflecting roller ( 102 ,  104 ) whereby the air turning bar ( 103 ,  105 ) and the deflecting roller ( 102 ,  104 ) carry out a reversing movement around an axis that runs orthogonal to the rotational position of the deflecting roller.  
     
     
         9 . Process in accordance with  claim 2  characterized by the fact that sheets ( 7 ,  17 ) are prepared with at least one sticky surface in that a film tube ( 1 ) is processed with at least one sticky peripheral surface.  
     
     
         10 . Process in accordance with  claim 3  characterized by the fact that sheets ( 7 ,  17 ) are prepared with at least one sticky surface in that a film tube ( 1 ) is processed with at least one sticky peripheral surface.  
     
     
         11 . Process in accordance with  claim 4  characterized by the fact that a film tube ( 1 ) is processed that has a sticky external surface and that while reversing only those surfaces of the cut film tubes ( 1 ) come into contact that had formed the internal surface of the film tube ( 1 ) before.