Area ratios of patterned coatings on rf electrodes to reduce sticking

Abstract

An electrosurgical system includes an RF current generator, a handle body, and an end effector. The end effector may include a first and a second energy delivery surface. At least a portion of either first or second energy delivery surfaces, or both, may include one or more patterned coatings of an electrically non-conducting non-stick material. The material may be deposited on a surface of, within a depression in, or on features extending from the energy surfaces, or through an overmolding process. The patterned coating may be formed from a coating of the material from which portions have been removed. An energy delivery surface has a first area, and the patterned coating has a second area. A ratio of the second area to the first area may be less than or equal to about 0.9, less than or equal to about 0.7, or less than or equal to about 0.5.

1 .- 33 . (canceled) 
     
     
         34 . An electrosurgical system comprising:
 an RF current generator;   a handle body; and   an end effector in mechanical communication with the handle body, the end effector comprising:
 a first jaw comprising a first energy delivery surface having a total surface area in electrical communication with a first terminal of the RF current generator; and 
 a second jaw comprising a second energy delivery surface in electrical communication with a second terminal of the RF current generator, 
 wherein a patterned coating of an electrically non-conducting non-stick material comprises a second surface area disposed on the total surface area, and 
 wherein a ratio of the second surface area to the total surface area ranges between 50% and 80%. 
   
     
     
         35 . The electrosurgical system of  claim 34 , wherein the electrically non-conducting non-stick material has a surface energy value between 1100 mJ/m2 and 5 mJ/m2. 
     
     
         36 . The electrosurgical system of  claim 34 , wherein the electrically non-conducting non-stick material has a surface energy value between 50 mJ/m2 and 40 mJ/m2. 
     
     
         37 . The electrosurgical system of  claim 34 , wherein the electrically non-conducting non-stick material has a surface energy value between 40 mJ/m2 and 12 mJ/m2. 
     
     
         38 . An end effector for an electrosurgical device, the end effector comprising:
 a first jaw comprising a first energy delivery surface having a total surface area and configured to be in electrical communication with a first terminal of an RF current generator; and   a second jaw comprising a second energy delivery surface configured to be in electrical communication with a second terminal of the RF current generator,   wherein at least a portion of the first energy delivery surface comprises a patterned coating of an electrically non-conducting non-stick material,   wherein a patterned coating of an electrically non-conducting non-stick material comprises a second surface area disposed on the total surface area, and   wherein a ratio of the second surface area to the total surface area ranges between 50% and 80%.   
     
     
         39 . The end effector of  claim 38 , wherein the electrically non-conducting non-stick material has a surface energy value between 1100 mJ/m2 and 5 mJ/m2. 
     
     
         40 . The end effector of  claim 38 , wherein the electrically non-conducting non-stick material has a surface energy value between 50 mJ/m2 and 40 mJ/m2. 
     
     
         41 . The end effector of  claim 38  wherein the electrically non-conducting non-stick material has a surface energy value between 40 mJ/m2 and 12 mJ/m2. 
     
     
         42 . The end effector of  claim 38 , wherein the patterned coating comprises the electrically non-conducting non-stick material disposed within a recessed feature fabricated in the first energy delivery surface. 
     
     
         43 . The end effector of  claim 42 , wherein the recessed feature comprises a circular feature. 
     
     
         44 . The end effector of  claim 42 , wherein the recessed feature comprises a rectangular feature. 
     
     
         45 . The end effector of  claim 42 , wherein the recessed feature comprises a linear feature. 
     
     
         46 . The end effector of  claim 45 , wherein the linear feature is disposed along or parallel to a longitudinal axis of the first energy delivery surface. 
     
     
         47 . The end effector of  claim 45 , wherein the linear feature is disposed along or parallel to a transverse axis of the first energy delivery surface. 
     
     
         48 . The end effector of  claim 38 , wherein the patterned coating comprises the electrically non-conducting non-stick material disposed on and in direct physical communication with an exposed surface of the first energy delivery surface. 
     
     
         49 . The end effector of  claim 48 , wherein the patterned coating comprises a coating of the electrically non-conducting non-stick material lacking a portion of the electrically non-conducting non-stick material. 
     
     
         50 . The end effector of  claim 49 , wherein the portion of the electrically non-conducting non-stick material comprises a circular portion of the electrically non-conducting non-stick material. 
     
     
         51 . The end effector of  claim 49 , wherein the portion of the non-stick material comprises a rectangular portion of the electrically non-conducting non-stick material. 
     
     
         52 . The end effector of  claim 49 , wherein the portion of the non-stick material comprises an elongated portion of the electrically non-conducting non-stick material. 
     
     
         53 . The end effector of  claim 49 , wherein the second energy delivery surface, having a second total area, comprises a second patterned coating of the electrically non-conducting non-stick material that is disposed on and is in direct physical communication with an exposed surface of the second energy delivery surface,
 wherein the second patterned coating comprises a third surface area, and   wherein a ratio of the third surface area to the second total surface area ranges between 50% and 80%.