What's it called when overlapping fonts in different colours create a kind of murky edge?

Question

When I'm designing a banner using Photoshop, and I use overlapping fonts in different colours, the points where the edges of the fonts meet are kind of murky. I'm sure there's a technical name for that, and some way I can overcome it. Any ideas?

Answer 1

You could use layers, so the colors would not be blended.

Answer 2

Are you talking about aliasing? It's hard to tell what you mean from your description...