Press mold for receiving a fiber-based blank, and method for reducing the water content in a fiber-based blank

Abstract

A press mold (20) for receiving a fiber-based blank, in particular a container (100, 100′, 100″) or a fiber-based closure element (300) for a container (100), for use in a microwave chamber (40). The press mold (20) is permeable to microwaves, and at least one gap (21) through which moisture can escape is formed on the press mold (20) in the closed state of the press mold (20). Additionally described is a method for reducing the water content in a fiber-based blank.

1 . A press mold ( 20 ) for receiving a fiber-based blank, in particular a container ( 100 ,  100 ′,  100 ″) or a fiber-based closure element ( 300 ) for a container ( 100 ), for use in a microwave chamber ( 40 ), wherein the press mold ( 20 ) is 5 permeable to microwaves, wherein at least one gap ( 21 ) through which moisture can escape is formed on the press mold ( 20 ) in the closed state of the press mold ( 20 ). 
     
     
         2 . The press mold ( 20 ) according to  claim 1 , wherein the at least one gap ( 21 ) is formed in a region of the press mold ( 20 ) which corresponds to a region on the fiber-based blank which is removed prior to use of a product made from the fiber-based blank. 
     
     
         3 . The press mold ( 20 ) according to  claim 2 , wherein the at least one gap ( 21 ) is formed on a region of the press mold ( 20 ) which corresponds to a neck of the blank. 
     
     
         4 . The press mold ( 20 ) according to  claim 1 , wherein it is formed in multiple parts and accordingly has one or more mold parting lines (T), wherein the at least one gap ( 21 ) or an additional gap ( 21 ) is formed on at least one of the mold parting lines (T). 
     
     
         5 . The press mold according to  claim 4 , wherein the at least one gap ( 21 ) is formed circumferentially along the entire mold parting line ( 21 ). 
     
     
         6 . The press mold ( 20 ) according to  claim 1 , wherein the at least one gap ( 21 ) opens into a moisture-discharging channel ( 22 ) which is arranged within a wall of the press mold ( 20 ). 
     
     
         7 . The press mold ( 20 ) according to  claim 1 , wherein the at least one gap ( 21 ) has a width of 0.04 mm to 0.1 mm. 
     
     
         8 . The press mold ( 20 ) according to  claim 1 , wherein additional openings are provided in the press mold ( 20 ) for discharging moisture. 
     
     
         9 . The press mold ( 20 ) according to the  claim 6 , wherein a moisture-discharging channel ( 22 ) is connected to a device for generating a negative pressure or an overpressure, so that a specific flow can be created in the moisture-discharging channel ( 22 ). 
     
     
         10 . The press mold ( 20 ) according to  claim 1 , wherein the press mold has a substantially uniform wall thickness. 
     
     
         11 . The press mold ( 20 ) according to  claim 1 , wherein bearing elements are provided on the press mold ( 20 ) in order to support the press mold ( 20 ). 
     
     
         12 . A method for reducing the water content in a fiber-based blank, in particular in a container ( 100 ,  100 ′,  100 ″) or a fiber-based closure element ( 300 ) for a container ( 100 ), comprising the steps of
 providing a wet fiber-based blank in a press mold, in particular in a press mold according to  claim 1 , 
 introducing an expandable tool ( 30 ) into the wet fiber-based blank, 
 expanding the expandable tool ( 30 ), wherein moisture displaced by the expansion is discharged through at least one gap ( 20 ) on the press mold. 
 
     
     
         13 . The method according to  claim 12 , wherein the wet fiber-based blank is exposed to microwaves after being provided in the press mold ( 20 ). 
     
     
         14 . The method according to  claim 13 , wherein moisture remaining in the blank is converted into a gaseous phase by the microwaves, and this phase is discharged through the at least one gap ( 20 ). 
     
     
         15 . The method according to  claim 12 , wherein the moisture is discharged by means of a forced flow. 
     
     
         16 . The method according to  claim 15 , wherein, for this purpose, in the press mold a moisture-discharging channel ( 22 ) is provided into which the at least one gap opens, wherein the flow in this moisture-discharging channel ( 22 ) is generated by negative pressure or by overpressure. 
     
     
         17 . The method according to  claim 12 , wherein a region of the blank, at which region the at least one gap ( 21 ) of the press mold ( 20 ) opens, is cut off from the blank after the water content has been reduced.