Is there a way to actually make polarplot gridlines black?

I know the documentation claims this is possible, but

pax = gca;
pax.GridColor = 'black';

keeps it as gray. I want the grid lines to be a dark solid black. When I move the figure to PPT or word, I get these measly gray lines that are almost undetectable when printed. Surely, we can just make the gridlines solid black right?

Answer 1

[Tom Veeken]

This will make the gridlines solid black

pax.GridColor = 'k';
pax.GridAlpha = 1;

Answer 2

[Image Analyst]

It's not 'black', it's 'k' - you know, from CMYK fame.

pax.GridColor = 'k';