Dianne
My husband is a printmaker and he wants to dye large sheets of very delicate gampi paper. Since these will never be washed I wondered if we could just stain it with the dye and not bother with adding soda ash. If soda ash is added will it have to be washed out to avoid getting a soda ash haze. 
Here is an image of his work IMG_5773.jpg 
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Jacquardmod Jacquardmod
This is a good question.  There are some questions as to whether lighfastness on un-reacted dye(stained in other words) is as good as the reacted dye on the fabric or in this case paper.  However, I'm sure he would take proper precautions with colored paper in any case, so I think it would be fine.  

If he needs something with better lighfastness, we have been using dye na flow lately to color paper, and I have been shocked at 2 things.  It is really even and looks like it has been dyed instead or painted.  It also seems to have no issue receiving ink and other media on it afterward, so it acts like a dyed paper and is of course lightfast and will not fade.  

Our basic dyes will give the most intense and beautiful colors on paper, but have the fading issues people associate with inexpensive papers.  
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