OBAs

[David McCormack]

Anyone know anything about the use of optical brightening agents in mountboard?

I avoid inkjet papers that contain them having read a lot of bad press on how they can discolour the paper over time, and anyway I prefer the warmer colour of the paper base. Having said that, I've been using photographic darkroom papers for longer than I care to mention and they all contain OBAs and I've never seen any noticeable discolouration of the paper.

My question is this... FATG conservation level states there should be no use of OBAs in mountboard so how do they make the boards so white? OBAs fluoresce under UV light and if I shine my UV torch on my conservation white mountboard samples they fluoresce very noticeably! This is easy to see when compared next to museum cotton boards that do not fluoresce.

Any thoughts?

[David McCormack]

Thought I would bump this topic with a couple of photos to illustrate what I'm on about.

The two sample mountboards are both white with one being described as meeting conservation level and the other museum level (the sample on top). They are photographed on a bog standard sheet of white paper that does contain OBAs. The first photo is under white light and the second a UV light. It is clear to me that the conservation board contains OBAs. If it doesn't, then why does it fluoresce under the UV light? You can also see that the core of the conservation board does not fluoresce. The backing paper also does not fluoresce. So I wonder if the standards do not apply to the face papers and only apply to the core and backing papers only?

I'm just curious and thought others maybe interested.

White-Light.jpg (162.61 KiB) Viewed 9484 times

UV-Light.jpg (89.76 KiB) Viewed 9484 times

[baughen]

I don't know whether this is directly associated with your mountboards but the FATG Update of February 2018 reported "It was brought to the attention of the Guild that some suppliers of mountboard have been using potentially misleading terms to describe their product, making it hard to be sure which of the three Mountboard Standards the boards belong in. We have been working with supplier members to address these issues.
We'd like to thank our members for their support in speedily bringing their descriptions into line with the terminology used throughout Guild standards and qualifications. Framer members may like to go to their supplier websites just to double check that they have correctly identified mountboard products.
However, there are still some mountboards that are not clearly labelled. For example, Spectra products from Centrado are termed 'conservation backed'. This might lead the busy framer to think that the boards are conservation products, but they aren't.
Under the Guild's Mountboard Agreement, which most UK and International producers of quality mountboard have signed up to, only products that are fully compliant with the standards for Conservation mountboard should be associated with the word."

[span2iels]

What Cliff has mention in his post is correct. There has been some concern that two suppliers have misleading information on their web-sites regarding the quality of mountboard. This was highlighted in January’s issue of A+FT in an article by Arqadia’s Managing Director Jonathon Burrage and I a Read, Reflect and Learn(RRL) article I wrote for the same issue. I have written a further article due to be published in the next edition of Arqadia’s 4Walls magazine.
For those who wish to read the RRL article it is attached as a pdf.

Please note this article was written when I was the Chair and a member of the Guild’s FSQC - I have since resigned. As such these comments should be attributed to myself.

[David McCormack]

Whether OBAs in the surface paper of mountboard have any detrimental effect on the artwork or not (and I suspect they don't) remains to be seen, but it would be nice to be told they are there. If my DIY UV torch tests are anything to go by (and they could be completely wrong ) then it is, if nothing else, interesting to see just how much OBA is used in boards that are listed as being of conservation standard.

And if you want to amuse yourself during your tea break, order one of these, turn out the lights and have a look around your workshop in the dark

001.jpg (500.95 KiB) Viewed 9305 times

002.jpg (838.69 KiB) Viewed 9305 times

[David McCormack]

A forum member has asked me to clarify what the photos above show

Optical brightening agents (OBAs) fluoresce under UV light.

They are chemical compounds added to fabric, papers, paint, plastic, washing powder and all sorts of things to make them appear whiter than white. They absorb ultra violet light and re-emit it as visible blue light giving the impression of it being whiter. This process is known as fluorescence. Under normal white light, which will contain UV light, the materials that contain OBAs will fluoresce and emit blue light as well as the reflected white light, giving the impression that the material is whiter than white. Generally, when we see something white that has a bluish tint as opposed to a yellowish tint, we perceive it as being whiter or brighter.

Because the human eye can't see UV light it is invisible. UV torches that you can buy like the one I've been using, have a filter to remove most of the visible white light. The light the torch emits is dark blue and contains invisible UV light. If you shine this torch light on a sheet of white paper, the paper reflects the blue light and therefore appears blue. It also reflects the UV light but we can't see it. However, if the paper contains OBAs, then they will absorb the UV light and re-emit it as brighter blue light. The more OBAs present the brighter the emitted blue light.

So, looking at my photo, the range of cotton-core museum boards in the top row are all dark blue because they have no OBAs in them at all. The two rows of conservation/white-core boards contain varying amounts of OBAs. All these boards are marked with a 'C' indicating they are conservation. Bright white, Snow white and Artic white are fluorescing the most and are therefore saturated with OBAs. Star white and Avillon white probably contain a fair amount of OBAs and Minuet contains some OBAs.

The thing is, OBAs can break down over time and stop working and even discolour the material they are contained in. However, we may never be aware of this deterioration and they probably won't have a detrimental effect on any artwork mounted with material containing them. But I will still avoid inkjet printing papers that contain them as I don't need whiter than white paper!

And the other thing is; the FATG says the following about conservation mountboard standards:

"2.17. The stock must be free of optical brightening agents."

So, if a mountboard is sold as fully meeting the FATG conservation standards how can it have OBAs in it?

Interestingly, Arqadia now lists Bright White as White Core Standard board on their website but Snow White is still listed as conservation as are the others. I have contacted Arqadia and asked if Snow White contains OBAs.... I'm awaiting a reply.

I need a cuppa tea now

[David McCormack]

Interestingly, Arqadia now lists Bright White as White Core Standard board on their website but Snow White is still listed as conservation as are the others.

Snow White and Arctic White are now listed as White Core (WC) on their website.

As a side note, I almost exclusively use Arqadia mount-board and their other products and think they are a good company to deal with, even when a problem does arise they deal with it very well. This topic is more about my curiosity and not a stab at Arqadia in any way at all.

[Pauline Hutchinson]

Thank you for flagging this, David. We have now checked the relevant product information with our supplier and I can confirm that you are absolutely correct - while Snow White and Arctic White contain no optical bleaching agents, they do contain optical brightening agents, and do not therefore qualify as conservation products.
We are now just completing a review to ensure that we can give customers a 100% guarantee that none of our conservation products contain any optical brightening agents in any part of their composition.
We take full responsibility for this misunderstanding around "OBAs" and are in the process of amending all records accordingly.
Meanwhile, we want to stress that the presence of optical brightening agents will have no detrimental effect on artwork. No gasses will be omitted and there will be no degradation whatsoever.
I apologise for the confusion around OBAs and, albeit unknowingly, for providing inaccurate information.
I have just spoken to the FATG and advised them that we have changed the description to Whitecore. Unfortunately our selectors will not be changed until we re-print.

If you have any further questions at all, please do not hesitate to contact me at pauline.hutchinson@arqadia.co.uk or on 01234 846309.

[David McCormack]

Thank you Pauline for confirming the presence of OBA's in those two boards and thanks for posting on the forum.