MITRA Forum Question Details

Hi

First a bit about cardboard. If it is standard cardboard the issue is not the cellulose but the lignin that is the issue. Low-grade wood pulp paper and board deteriorate and become yellow and brittle very quickly (think newspaper). I really first have to ask, why cardboard? If you are thinking the standard variety cardboard, I cannot really think of any great remedies for it deficits. Is it the corrugated surface topography? If so, that surface would likely be removed in this future hypothetical “relining” (actually that would be a transfer and it would require hundreds of hours meticulously removing the old cardboard under a microscope using a scalpel). The only way this separation could be made easier would be to have an easily reversible interlayer. Certainly, the board could be “encapsulated” in layers of more stable materials. Both of these options are possible, but this still begs the question, why cardboard? The only reasons I can think of are topography, weight, or economy and there are probably better materials to achieve these qualities if we understand your reasoning.  

If you are interested in both the surface topography and the light weight, I would suggest that you use acid free blue board which is used for more archival purposes. If you really like the color of standard cardboard (although this does not seem to be the impetus for using it as you mention the willingness to apply acrylic gesso) I would coat the blue board with a couple of layers of acrylic dispersion paint of the appropriate color.  

Could you give us the reasons for the choice and perhaps a more suitable answer can be formulated.

​Hi - There is really nothing redeeming about generic, brown, common industrial cardboard - if that is what you are referring to - other than being cheap, and a part of that inexpensive cost is based on not needing to produce a product with much longevity. It is invariably acidic and with a high lignin content. However 'cardboard' can also be a catchword with a broad reference, and the following document does as good a job as I have seen in describing what you would want to look for in a 'cardboard' that was acceptable for use:

http://preservart.ccq.gouv.qc.ca/documents/carton_en.pdf

And, as a rule, if the manufacturer is unwilling to speak to the content of their product at the most basic level I would recommend moving on to something you can have more confidence in.

Also  - and I say this with all due respect - why on earth would you want to use something where you would consider going through all these steps

• "saturated the cardboard with something (gelatin/methylcellulose/PVA/wall paint primer?), then
• gave it three layers of gloss medium (first diluted 1:1), then
• put on two layers of acrylic ground
  
  and then painted on it? I'm not sure if three layers of medium plus two layers of ground wouldn't be too excessive."

​Hi -

Thanks for the clarification. Could you point to a link for the product you are looking at? And in terms of solid panels, would you consider aluminum composite panels, such as Dibond? They are very dimensionally stable and should have excellent long-term durability. In terms of lightweight paper-based alternatives - although I realize what you are thinking of is something different - if you have a good conservation or framing supply retailer you could look into things like the following:

http://www.talasonline.com/Heritage-Corrugated

http://www.masterpak-usa.com/cat_214_multiusebd.htm

http://www.talasonline.com/Tycore-Hexamount-Panels

Also, while there is some back and forth on whether Sintra (a closed cell rigid PVC panel)  raises any conservation concerns, you can still find many sources that recommend it for use in museum storage and case construction, and we have had good results using Sintra and Sintra-like panels with acrylics:

http://www.conservation-wiki.com/wiki/Sintra

http://www.sintrapvc.com/

And finally, there are some forms of MDF that do not have formaldehyde and likewise have found some acceptance in conservation circles, such as Medex:

http://www.hardwoodweb.com/architectural/docs/MedexSpecApril08.pdf

But whether that or a similar product is available where you are is another matter.

Hope some of these alternatives help.

​Thanks Sarah these are all great suggestions....as a conservator I would support using any of these materials over board made from wood pulp.

Really, there are no good reasons to use common cardboard. Acid Free blue board is vastly preferable for the reason enumerated above. I have a query into another moderator for more info about your question posed on the other thread.