I've put the photo back in the Pirates Pennant and this is what it looks like after a clean. I'm pretty pleased.
I also picked up a Phillies "Atomic Cap" pennant in a misc lot. It was pretty badly discolored and it cost me next to nothing. So I decided to experiment with different approaches.
First I soaked it in Oxiclean for a couple of hours. That made it better but not much. So I soaked it in Oxiclean again and left it overnight. That was my mistake. The red dye in the graphics started to disolve because I left it soaking too long. After all of that, discolored white areas still weren't great.
At this point, the graphics were damaged so I decided to try bleach to see what it would do. That worked great on the white body of the pennant. I suspect if I started with bleach, it would have ended up perfect.
My lessons:
- Oxiclean works well but only use if for short amounts of time (e.g. an hour or two at most)
- If using Oxiclean, what for any bleeding of the graphics. As you as you see that, take it out and stop.
- Bleach on white pennants, can't be beat.