Clean line edges

[BobC]

Total newb here. I couldn't find an answer to this in the search, so I hope I'm not repeating a question. 

I'm trying to find out how to get clean edges where 2 colors meet. For instance,  if I draw a black line on a white background there is a one pixel wide gray line around all edges of the black line where it meets the white background (see attachment).

Is there a setting or other way to stop this from happening, make the colors meet without discolored pixel edge, before I even make my line, so that I don't have to keep zooming in and cleaning up the edges manually? (Which is super tedious).

In case it helps, the image I'm currently working on is 6500x6500 at 300dpi.

Thanks for your time! 

[BobC]

 

5 minutes ago, welshblue said:

Select -  Anti Aliasing Disabled  ... next to the Solid Colour text in your screenshot

 

That did it! Thank you so much!

[BobC]

Well, anti aliasing disabled looks great on straight lines,  but now I've noticed it looks horrible on curved lines and will likely make prints look bad. 

But how does anti aliasing look printed? Oy!

[toe_head2001]

19 minutes ago, BobC said:

But how does anti aliasing look printed?

Assuming the DPI is very high, it looks great.

300 DPI is really the absolute minimum you'd want to do. I recommend going higher, to at least 600.