Element border problem

I have a polygon element which is rasterized by using

IGlobeGraphicsElementProperties asd2 = new GlobeGraphicsElementProperties();
asd2.DrapeElement = false;
asd2.Rasterize = true;

In the first picture polygon element is seen with no border however when zoomed in it is seen with a gray border(In the second picture). Is there a way not to show this border? Can i reach border property of this element?

Thanks in advance

Attached Thumbnails