imageA reader who is a high school chemistry student writes:

In Rogers’s book on page 78 I read that “Image color can be chemically reduced with diimide, leaving colorless fibers.”  I’ve seen this mentioned on several websites and I’ve read that the image does not respond to ordinary bleaching.

My teacher and I looked it up in Wikipedia. Neither one of us can understand what it says.

What does it mean?  What does it rule in or rule out? 

Good questions? I just looked up reductions with diimide in Wikipedia and I could not understand it either.