Offline roll to roll web coating

Abstract

A coating system for coating a web of paper includes spaced apart support rollers, a guide roller, a tension roller, a motor, a dispenser, and a control system. The support rollers support respective spools of paper. The guide roller is configured for guiding the paper along a path between the spools of paper. The tension roller is positioned along the path and is configured to engage the paper. The motor is operable to rotate the support rollers and/or the tension roller. The dispenser is fixed proximal to the path and is operable to guide liquid coating onto the paper located on the path. The control system is in communication with the motor and is configured to direct the motor to cause the paper to shift in either direction along the path between the spools.

1 . A coating system for offline roll-to-roll web coating of paper, the coating system comprising:
 one or more first support rollers for supporting a first spool of paper;   one or more second support rollers spaced apart from the one or more first support rollers and provided for supporting a second spool of paper;   one or more guide rollers configured for guiding the paper along a path between the first spool of paper and the second spool of paper;   one or more tension rollers positioned along the path and configured to engage the paper;   one or more motors operable to rotate at least one of the one or more first support rollers, the one or more second support rollers, and the one or more tension rollers;   a dispenser fixed proximal the path and operable to guide liquid coating onto the paper located on the path; and   a control system in communication with the one or more motors and configured to direct the one or more motors to shift the paper in either direction along the path between the first spool and the second spool.   
     
     
         2 . The coating system of  claim 1 , further comprising one or more metering pump operable to supply the liquid coating to the dispenser. 
     
     
         3 . The coating system of  claim 2 , wherein the control system is in communication with the one or more metering pump and configured to direct the metering pump to supply the liquid coating at a predetermined flow rate corresponding to at least one of a desired coating thickness, a linear speed of the paper shifting along the path, or a width of the paper. 
     
     
         4 . The coating system of  claim 1 , further comprising a plurality of air nozzles directed toward the path the paper traverses downstream from the dispenser, wherein the plurality of air nozzles are configured to force air toward the paper traversing the path. 
     
     
         5 . The coating system of  claim 4 , wherein the plurality of air nozzles are configured to force heated air toward the paper traversing the path. 
     
     
         6 . The coating system of  claim 5 , further comprising a heater operable to connect to a pressurized air source, heat the pressurized air, and supply the pressurized air to the plurality of air nozzles. 
     
     
         7 . The coating system of  claim 6 , wherein the heater is an electric heater. 
     
     
         8 . The coating system of  claim 7 , wherein the control system is configured to adjust a temperature setting of the heater. 
     
     
         9 . The coating system of  claim 8 , further comprising an air pressure regulator in fluid communication with the plurality of air nozzles and in electrical communication with the control system, wherein the control system is configured to direct air pressure regulator to obtain a desired air flow rate at the plurality of air nozzles. 
     
     
         10 . The coating system of  claim 1 , further comprising a non-contact sensor in communication with the control system and configured to detect a property related to an amount of paper located on at least one of the first spool or the second spool, and transmit one or more signals representative of the property to the control system. 
     
     
         11 . The coating system of  claim 10 , wherein the control system is configured to direct the one or more motors to shift the paper from the first spool to the second spool until a threshold amount of paper has been shifted based at least on the one or more signals, and direct the one or more motors to shift the paper back from the second spool to the first spool. 
     
     
         12 . The coating system of  claim 1 , further comprising a second dispenser fixed proximal the path and operable to guide liquid coating onto the paper located on the path. 
     
     
         13 . A method for coating a web of paper, the method comprising:
 (a) pulling, via one or more powered tensioning pinch rollers, the web of paper from a first spool;   (b) guiding, via one or more idle rollers, the web of paper along a path;   (c) dispensing, via one or more dispensers positioned at a first location along the path, a liquid coating on a portion of the web of paper;   (d) forcing air toward the portion of the web of paper at a second location along the path that is downstream of the first location;   (e) winding, via one or more winding rollers, the coated web of paper on a second spool;   (f) pulling, via the one or more powered tensioning pinch rollers, the web of paper from the second spool;   (g) winding, via one or more winding rollers, the coated web of paper on the first spool; and   (h) repeating steps (a) through (g) until the coating on the web of paper obtains a desired thickness.   
     
     
         14 . The method of  claim 13 , further comprising prior to step (f) detecting, via one or more non-contact sensors, a remaining amount of paper on the first spool. 
     
     
         15 . The method of  claim 13 , wherein step (c) comprises supplying, via one or more metering pump, the liquid coating at a flow rate based at least in part on a desired coating thickness, a linear speed of the paper shifting along the path, or a width of the paper. 
     
     
         16 . The method of  claim 13 , wherein the one or more powered tensioning pinch rollers and the one or more winding rollers are synchronized so that the paper shifts along the path at a desired linear speed. 
     
     
         17 . A coating system for offline roll-to-roll web coating of paper, the coating system comprising:
 one or more first support rollers for supporting a first spool of paper;   one or more second support rollers for supporting a second spool for receiving paper from the first spool;   a plurality of guide rollers configured for guiding and unwinding the paper from the first spool of paper such that the paper traverses a path to the second spool; and   a waterfall dispenser fixed above the path and including:
 a pressure chamber for receiving liquid coating, and 
 a longitudinal narrow gap in fluid communication with the pressure chamber and through which the liquid coating flows from the pressure chamber onto a width of the paper being unspooled from the first spool of paper. 
   
     
     
         18 . The coating system of  claim 17 , further comprising a control system in communication with the plurality of guide rollers and configured to direct the plurality of guide rollers to shift the paper in either direction along the path between the first spool and the second spool. 
     
     
         19 . The coating system of  claim 17 , further comprising a first plurality of air nozzles directed toward the path the paper traverses downstream from the waterfall dispenser, wherein the first plurality of air nozzles are configured to force air toward the paper traversing the path. 
     
     
         20 . The coating system of  claim 19 , wherein the waterfall dispenser is a first waterfall dispenser, further comprising:
 a second waterfall dispenser positioned downstream of the first plurality of air nozzles and including:
 a pressure chamber for receiving liquid coating, and 
 a longitudinal narrow gap in fluid communication with the pressure chamber and through which the liquid coating flows from the pressure chamber onto a width of the paper being unspooled from the first spool of paper; and 
   a second plurality of air nozzles directed toward the path the paper traverses downstream from the second waterfall dispenser, wherein the second plurality of air nozzles are configured to force air toward the paper traversing the path.