I second Jane’s questions & the suggestion of a print rather than a negative. Most people won’t “get” a negative as well as the positive image, unless they are used to looking at them. Now days, most people aren’t. To properly show the image, the emulsion side would have to be facing down to be correctly oriented.
A question I have is how will these be viewed if they are not backlit, such as a light box? That could be more damaging than the ambient light and could change the temperature in the display. Perhaps, if you have a scan of the negatives, you could print it onto transparency film and use a “mock” version of it with a photo of the real plate as a part of the display?
We have experience with glass plate negatives, nitrate, and the various types of acetate negatives, as well as polyester supports. If you have questions regarding your collections, printing, housing for storage, or digitization, we can help with some answers. We have printed & digitized glass plates & negatives for several collections.
Contact us via email: firstname.lastname@example.org, if you wish.
All the best,
Kim Du Boise, Conservator
PhotoArts Imaging Professionals