Preserving Emulsion Paper

[DenseFilm500]

I heard before from my professor that emulsion paper is archival and can last for decades, but I was wondering if there are certain conditions that must be met for the storage of the paper that effects its hypothetical shelf date?

[Niels - NHSN]

All you need, but probably more than you want to know:

https://www.loc.gov/preservation/care/photo.html

Enjoy reading.

[glen_h]

3 hours ago, NHSN said:

All you need, but probably more than you want to know:

https://www.loc.gov/preservation/care/photo.html

Enjoy reading.

There are more details in other loc.gov pages, and some linked nps.gov pages.

 

I believe I was reading in one of these, mentioned in an earlier discussion, that LOC plans for a 500 year life.

In the case of photographs, I believe that is for the film negative more than a print.

 

Also interesting is the work on preservation of digital images.

In many ways, digital preservation is harder, as it depends on having the right

systems for reading the data.  It seems unlikely that there will be CD-ROM

drives in 500 years that can read today's CDs, even if they last that long.

(Consider computer technology 500 years ago!)

 

In any case, there are many people working on this, and many articles about it.

 

 

[Alan Marcus]

Chemical based photographic print paper --- Black & white version, the image is comprised of silver suspended in purified gelatin coated on paper. The image you see is microscopic tufts of silver deposited in proportion to the blackness of the image at that location. Assuming that the developing process was handled to specifications, you can expect archrival results. Archrival meaning is 100 years. That being said, the silver that comprise the image is not inert. The main enemy is sulfur. Should sulfur fumes or dust contract the emulsion, the silver will tarnish (turns brown). In the past, this was a big problem because homes were heated, and machines powered by the burning of coal. In other words, coal smoke loaded with sulfur fumes. The countermeasure is to tone the print sepia or brown. This produces a warm tone and renders the silver image archrival. 

Also, it is not uncommon that the black & white print will be improperly fixed and improperly washed. Such prints have a short lifespan. 

The gelatin binder that holds comprises the emulsion is made from bone and hides of cows. Gelatin is tasty treat for microbes. To fort this action, we store photo prints in a cool dry environment. 

Color chemical-based prints are comprised of dye imbedded in gelatin. The dyes used are organic as is the gelation. Again, microbes can nibble plus organic dyes are said to be fugitive meaning they will fade over time. Color prints developed to specification will survive the 100-year test, but the dyes have a half-life of about 50 to 75 years,  

 

[Rick Helmke]

If your question is how long can paper be preserved before use it has much to do with how it’s stored. When our lab bought in bulk we would order what we expected to use in a year. When it arrived we froze it until needed and never has a problem. I do the same now but buy and use less. If your question is how long can a finished print be expected to last, it depends on a few things. In b&w, if properly fixed, washed and dried it can last for decades. There’s one framed on my wall right now I printed in 1977. It looks fine. As for color prints it has a lot to do with the materials used. Standard prints from negatives seem to do well but if displayed in a window and exposed to direct sunlight every day, I’ve seen them fade badly. Cibachrome otoh seems to be archival. I have Ciba  prints made in the early/mid 90’s that look great. I wish they would bring it back. 
 

Rick H.