Polygons with no outline draw with fine outlines when exported to Portable Document (PDF), Adobe Illustrator (AI), or Encapsulated PostScript (EPS) formats from ArcMap and viewed in Adobe applications.
This is a known issue because of how PostScript entities, such as PDF, are drawn on the screen in such applications as Adobe Reader, Illustrator, etc. Unless the data is topologically correct with true shared edges, fine lines may be visible between polygons when viewing ArcMap exported files in the format of PDF, AI, or EPS in such applications as Adobe Reader, Illustrator, etc.
However, the print out of the exported ArcMap documents in PDF, AI, and EPS do not show these lines.
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