These gridlines are called the graticule and are quite easy to remove. First, go to the Setup Menu in LabChart and select the "Display Settings..." option. In the settings window that appears, left mouse click the Graticule Hide radio button, and then left mouse click the Ok button.
The graticule will now be removed from all views in LabChart as well as any images of these views exported out of the software.
For further technical assistance with this or any other issue, please contact ADInstruments Technical Support by clicking HERE.