Laser film debonding method

Abstract

A laser-based coating removal method debonds a film from a substrate rather than ablating the film. A laser light is transmitted through a transparent film to an underlying bonding layer for bonding the film to one or more additional films and/or a substrate. The laser light is absorbed at the bonding layer and the transparent film is released. In some embodiments, after the transparent film is released it is able to be physically removed.

1 . A method of removing a protective film from a substrate comprising:
 a. transmitting a laser light through the protective film to an underlying and separately applied bonding layer, wherein the bonding layer adheres the protective film to the substrate; and   b. absorbing the laser light at the bonding at the layer,   wherein as the laser light is absorbed at the bonding layer, the protective film is released.   
     
     
         2 . The method of  claim 1 , wherein the protective film comprises polyurethane. 
     
     
         3 . The method of  claim 1 , wherein the substrate comprises fiberglass composite or carbon fiber and epoxy composite or composite foam material. 
     
     
         4 . The method of  claim 1 , wherein the protective film ranges from 0.001 inches to 0.300 inches thickness. 
     
     
         5 . The method of  claim 1 , wherein the laser wavelength is in the near infrared. 
     
     
         6 . The method of  claim 1 , wherein the laser wavelength is 1064 nanometers. 
     
     
         7 . The method of  claim 1 , wherein the laser scanning method is machine controlled. 
     
     
         8 . The method of  claim 1 , wherein the scanning method is manual such that a laser work head is moved by hand by over the work piece. 
     
     
         9 . The method of  claim 1 , wherein the laser comprises a pulsed Nd:YAG laser. 
     
     
         10 . The method of  claim 1 , wherein the laser average power is at least 10 watts. 
     
     
         11 . The method of  claim 1 , wherein the laser repetition rate is at least 100 per second. 
     
     
         12 . The method of  claim 1 , wherein a laser spot size ranges from 0.1 mm to 10 mm diameter. 
     
     
         13 . A method of removing a protective film from a substrate comprising:
 a. transmitting a laser light at a wavelength to transmit through a first protective film layer to a separately applied adhering interface between the first protective film layer and a second protective film layer; and   b. absorbing the laser light at the adhering interface between the first film layer and the second film layer,   wherein as the laser light is absorbed at the adhering interface, the first film and the second film are debonded.   
     
     
         14 . The method of  claim 13 , wherein the first film layer and the second film layer comprise polyurethane. 
     
     
         15 . The method of  claim 13 , wherein the first film layer remains intact as the first film and the second film are debonded. 
     
     
         16 . The method of  claim 13 , wherein the protective film layers range ranges from 0.001 inches to 0.300 inches thickness. 
     
     
         17 . The method of  claim 13 , wherein the laser wavelength is in the near infrared. 
     
     
         18 . The method of  claim 13 , wherein the laser wavelength is 1064 nanometers. 
     
     
         19 . A method of removing one or more protective films from a substrate comprising:
 a. transmitting a laser light at a wavelength to transmit through one or more than one protective films; and   b. absorbing the laser light at a separately applied adhering interface between a last film above the substrate and a second to last film,   wherein as the laser light is absorbed at the adhering interface, the last film and the second to the last film are debonded.   
     
     
         20 . The method of  claim 19 , wherein the last film above the substrate and the second to last film comprise polyurethane. 
     
     
         21 . The method of  claim 19 , wherein the second to last film remains intact as the last film and the second to the last film are debonded. 
     
     
         22 . The method of  claim 19 , wherein the protective film ranges from 0.001 inches to 0.300 inches thickness. 
     
     
         23 . The method of  claim 19 , wherein the laser wavelength is in the near infrared. 
     
     
         24 . The method of  claim 19 , wherein the laser wavelength is 1064 nanometers. 
     
     
         25 . A laser-based coating removal system to remove a protective film from a surface, the system comprising:
 a. a laser source configured to provide a laser pulse;   b. a laser scanning head coupled to the laser source and configured to direct the laser pulse onto a position on the surface, wherein the laser pulse is configured with a wavelength such that the laser pulse transmits through the protective films to an underlying and separately applied bonding layer, wherein the bonding layer adheres the protective film to the surface, and wherein as the laser light is absorbed at the bonding layer, the one or more protective films are released.   
     
     
         26 . The system of  claim 25 , wherein the laser scanning head is machine controlled. 
     
     
         27 . The system of  claim 25 , wherein the laser scanning head is manually controlled such that the work head is moved by hand by over the work piece. 
     
     
         28 . The system of  claim 25 , wherein the protective film ranges from 0.001 inches to 0.300 inches thickness. 
     
     
         29 . The system of  claim 25 , wherein the laser wavelength is in the near infrared. 
     
     
         30 . The system of  claim 25 , wherein the laser wavelength is 1064 nanometers. 
     
     
         31 . The system of  claim 25 , wherein the laser comprises a pulsed Nd:YAG laser. 
     
     
         32 . The system of  claim 25 , wherein the laser average power is at least 10 watts. 
     
     
         33 . The system of  claim 25 , wherein the laser repetition rate is at least 100 per second. 
     
     
         34 . The system of  claim 25 , wherein a laser spot size ranges from 0.1 mm to 10 mm diameter.