Does Dibond contain OBAs?

[shadowblade]

Thing is we have had first class research done on photo materials, digitql and analogue, primarily because they are so disparite in quality that they have to be tested, but we don't have the same kind of research invested into mounting materials.

We do know from RIT that dry mounting with good thermo plastics has turned out to be a very viable method of mounting, when mounting to rag boards. And even protects the gelatin silver prints! And we know that mounting with PVA book binders glue is excellent for very long term stability and chemical free content. We know that plexi yellows.

Plexi/acrylic yellows a lot less than most other plastics, and many glasses.

Regardless, adhesives can fail and substrates crumble, scratch or break; what is needed isn't so much an unbreakable substrate or failproof glue, but an easily-reversible method of flat-mounting a print to Dibond or face-mounting it to acrylic or glass.

A lot of this depends on the strength and durability of the print itself, rather than the strength of the adhesive. PVA works very well, but the print also needs to survive reversal. So does Glamour II. Flat-mounted canvas works well, due to its strength, but doesn't exactly lend itself to a smooth or paper-like texture.

I've had luck spraying Breathing Color Pura Smooth and Pura Velvet with Timeless Gloss. Dilute it 4 parts Timeless to 1 part distilled water, with a drop of Photo-Flo, then spray on one or more thin layers via HVLP (the more layers, the more gloss). Or you can kill the gloss on the front with a light spray of Timeless Matte or Satin after you finish with the diluted Gloss. It soaks through the image layer and inkjet layer, deep into the paper base, forming a thick conglomerate of image, receptive layer and paper fibres, all held together and encapsulated in Timeless polymer that behaves as a single piece and won't come apart. Repeat on the back of the print and the whole thing becomes as tough as canvas. I'd expect it to hold up very well to repeated mounting and reversal.

But in this era most of us are not dry mounting to rag board anymore or using wet glue, we're mounting to dibond or sentra, or worse and there are just no verifiable figures on this stuff (and it ain't cheap to do boys). I put the blame on galleries and museum personnel. They just don't seem to know or care about anything in this regard anymore. They should know, it's their job. But we live in a throw away culture. What else is new.

PVA essentially forms an impervious barrier between the substrate and the print, preventing them from interacting. That's why you can mount a print to acid-containing wood boards using PVA without any effect on the print. It's also reversible. Dry-mount tissues do much the same (and both also protect the back of the print from gases) and some are acid-free. The only issue is reversability - impossible with some, difficult with others.

Really the safest way to mount a pigment print is to matt it behind a rag matt on a rag mount and frame behind glass or plexi. Only problem with that is it is considered old fashioned, and maybe it is. I don't even like to show prints like that anymore and I'm  a fascist when it comes to longevity.

From a photographer's (rather than archivist's) perspective, we really need more data and better methods for prolonging the life of prints on open display, rather than better cold/dark storage methods. After all, photos are meant to be displayed - a print kept in a dark freezer somewhere might be safe, but also isn't very useful.

Or you can bypass most of these issues and find a way to print directly onto aluminium sheet, titanium sheet or Dibond. With a sufficiently-lightfast white ink, you don't even need a white-coated substrate...

[Geraldo Garcia]

(...) But in this era most of us are not dry mounting to rag board anymore or using wet glue, we're mounting to dibond or sentra, or worse and there are just no verifiable figures on this stuff (and it ain't cheap to do boys). I put the blame on galleries and museum personnel. They just don't seem to know or care about anything in this regard anymore. They should know, it's their job. But we live in a throw away culture. What else is new.

Really the safest way to mount a pigment print is to matt it behind a rag matt on a rag mount and frame behind glass or plexi. Only problem with that is it is considered old fashioned, and maybe it is. I don't even like to show prints like that anymore and I'm  a fascist when it comes to longevity.

That is exactly my feeling. I have seen high end galleries selling prints mounted on sintra with cheap adhesive using the sales-pitch of "pigmented prints on rag paper that will last centuries". Most artists don't want to hear about longevity issues, same with art merchants. It is almost as if they want to be able to deny knowing about it.

[shadowblade]

That is exactly my feeling. I have seen high end galleries selling prints mounted on sintra with cheap adhesive using the sales-pitch of "pigmented prints on rag paper that will last centuries". Most artists don't want to hear about longevity issues, same with art merchants. It is almost as if they want to be able to deny knowing about it.

Many artists (and some photographers) don't want to know about the technical side of things at all - some, it seems, choose to deliberately not know, and almost take pride in not knowing!

That in itself isn't so bad, since sign printers and other commercial printers certainly do know about the technical side of things, and care a lot about longevity (a year outdoors being equivalent to 100 years or more indoors in terms of UV and gas exposure, and probably a lot more in terms of water and other physical damage).

Trouble is, commercial printers care a lot about speed and not so much about quality, and print in huge sizes that most photographers will never need (even 60" is bigger than most will ever need - 44" already allows for a 40x60" print or 40x120" panorama). So we end up with inks and substrates that can last a decade outdoors (and maybe a millennium indoors), delivered through $500k, 5m-wide printers with four inks, no light inks and large droplets aimed at speed rather than image quality. Great if you need a billboard printed, but not so practical if you're trying to print 20x30" fine art onto a durable metal, glass or ceramic substrate. Meanwhile, the art- and photo-oriented printers optimised for image quality can't print on thick, durable substrates, so we're stuck with mounting.

[stcstc31]

epsons can print on 1.5mm substrates

i often print on mountboard for corporate jobs


also have a coated aluminium and copper sheet that will go through the printer. it then has to be coated (varnished or something to protect it though

[shadowblade]

epsons can print on 1.5mm substrates

i often print on mountboard for corporate jobs

That's useful for printing on specialty, ultra-thick papers, but still too thin for a standalone piece that doesn't require mounting and all its associated issues. For directing printing of standalone pieces, you're really looking at a minimum 3mm thickness capability, ideally 6mm.

It'd be nice if there was some sort of 'pigment transfer' process, similar to the dye-sub method used for dye-sub aluminium prints.

also have a coated aluminium and copper sheet that will go through the printer. it then has to be coated (varnished or something to protect it though

It also needs to be mounted. It's not thick enough to be a standalone piece.

[stcstc31]

nah i have done them with just subframe, 1.5mm thick aluminium is pretty stiff. havent done big sizes though

[shadowblade]

nah i have done them with just subframe, 1.5mm thick aluminium is pretty stiff. havent done big sizes though

Yeah, wouldn't work so well for 20x30" and larger - particularly for long, wide panoramas. Although mounting an aluminium sheet is likely far easier and far more reversible than a fragile piece of paper.

That said, you'd also need Breathing Color or Hahnemuhle to release inkjet-coated aluminium plate with good image permanence. The current metal foils and sheets don't really cut it from that standpoint.

[stcstc31]

actually have done up to that size (30*20)

i use a 1" cube aluminum sub frame on the back, makes it very stiff

the trick is what you coat them with. it can give a serious amount of robustness to them

[shadowblade]

actually have done up to that size (30*20)

i use a 1" cube aluminum sub frame on the back, makes it very stiff

the trick is what you coat them with. it can give a serious amount of robustness to them

I'm really talking about *over* that size - 20x30 is just about as small as I go (and most prints I make are panoramas of some sort, meaning 16x48" or larger - not great for stiffness). The last thing you want is for someone to bump into something during installation or transport and a corner to bend...

Anyway, I think we'll have to wait for 24-44" photo/art-oriented UV printers for decent direct output onto metal outside of a signage factory with a $500k printer. The current 'inkjet-ready' metal sheets seem more designed for novelty than for serious, long-lived works (don't think there is even an option for metal with a white background - it's all about the metallic appearance, rather than using metal as a durable substrate), and it doesn't seem like Hahnemuhle, Breathing Color or anyone else with a long-lived, high-quality inkjet coating has any interest in making inkjet-compatible metal.

[shadowblade]

Really the safest way to mount a pigment print is to matt it behind a rag matt on a rag mount and frame behind glass or plexi. Only problem with that is it is considered old fashioned, and maybe it is. I don't even like to show prints like that anymore and I'm  a fascist when it comes to longevity.

That's probably why, these days, I seem to be producing far fewer large paper prints than I used to, and far more dye-sub metal and canvas.

Most images look great on one paper or another. For black-and-white images, I'd say that paper is very hard to beat on almost any other medium - Canson Etching, Hahnemuhle Photo Rag Baryta and Platine Rag especially. Trouble is, it doesn't hold up well when displayed without glass or frame - doubly so in a busy environment.

A new, super-tough paper, or some way to 'fix' existing papers so that they become as tough as painted or sprayed canvas without changing its appearance, would be very welcome. Timeless on Pura Velvet works well, but the appearance of the paper is still visibly altered and the print will still be destroyed if someone scrapes their fingernail across it.

[enduser]

I don't have any references, but I recall seeing some Chinese and Swiss printers where they had transferred the paper movement controls to the ink carriage in some way that the substrate remains static and all movement takes place at the carts -  both forward and side to side.  The heads and inks slowly move forward over the substrate.  Then the platen that the substrate sits on had a simple manual vertical adjustment range of about 1 inch.

In at least one example I saw it was an Epson large format that had been modified. It seemed like the sort of thing a competent person with a good workshop and a bit of electromechanical knowledge could do?