View Full Version : Substrates for Shooting in Camera - FILM, Acetate, PET (polyester), Glass, etc.
05-10-2012, 11:26 AM
These people are very helpful and may have a suitable product with a commercially/volume acceptable offer
I use them at work for printable films for labels :-)
05-10-2012, 12:10 PM
Excellent resource. Thank you for posting it.
There is one thing to watch out for when looking for suitable film (besides thickness). Almost all treated polyester films today are subbed for solvent-based fluids. Without exception that I'm aware of (and there is an encyclopedia of things I'm not aware of), this means they are hydrophobic, i.e. shed and bead emulsion, and/or go all goopy and gloppy. You want to be sure to ask for hydrophilic subbing.
05-10-2012, 12:28 PM
Almost all treated polyester films today are subbed for solvent-based fluids. Without exception that I'm aware of
Except those I mentioned earlier which are subbed for water based UV inks.
05-10-2012, 12:44 PM
There are many PET materials available in 0.125mm and 0.175mm thicknesses which either have surface coatings or surface treatments to aid the screen printing of inks.
The company I work for uses a lot of this material which we buy in 2' x 3' sheets.
For our purposes, there are two types of coating/treatment. One is suitable for solvent based inks and the other for water based UV cured inks. It is the latter type which I think would be more suitable for emulsion.
A while ago, I collected together some samples for Denise to try out but to my shame, I have just realised that they are probably still in my drawer at work. If you're reading this Denise, please accept my apologies. I will try to post the pieces soon.
There are also some polycarbonates and polyester/polycarbonate blends which might be suitable. I will go through what we have at work tomorrow and post other materials/sources.
Note: Mylar is a DuPont trade name, not a general term for polyester.
i see that macdermid have a distributor in my country, but what i see from their website it's just confusing for me. which product is usable for this application?
05-10-2012, 12:58 PM
The UV inks are an exciting development. UV-cure technology seems like near-magic to me. I use a UV-curable adhesive to make glass emulsion wells. I can work under a yellow bug light for many minutes, but the second (make that nanosecond!) it sees UV light, it sets up and adheres like the original glass. I have had my first attempts (Fail!) outside in my garden as decoration for four years. Rain, sun, frost...and they still are glued rock solid. Amazing.
With the inks, though, is it a matter of substrated material or the inks themselves? Here's some info: http://www.signindustry.com/flatbed_UV/articles/2003-04-15-JL_UVpt2.php3
I plucked the following quote out. It seems to suggest that the reason the UV inks work so well is that they dry faster than they can penetrate the subbing. If that's the case, they could go on any substrate, which isn't the case with silver gelatin emulsions. Of course, this is just one article and no doubt the picture is complicated and evolving. Gotta love science! I'd love to hear more about the films you're working with and perhaps even get my hands on them (hint, hint :))
Water-based UV inkjet technology is attracting attention because it uses water as a diluent to produce lower viscosity. Water-based UV inks are formulated with UV-curable resin emulsions. But there are drawbacks with this technology. The system needs to get rid of the water before the UV lamp cures the ink.
“Getting rid of the water is difficult as you want to cure as quickly as possible to prevent undesirable dot gain, wicking or feathering into the substrate,” says Emery. “If water is present, then the ink will not adhere to the substrate. UV curable inks that are 100 percent solids will be the first product available.”
05-10-2012, 01:35 PM
what i see from their website it's just confusing for me. which product is usable for this application?
This material, CT5 is what we use a lot of. We print solvent based conductive inks and water based UV cured dielectric inks onto it.
05-10-2012, 01:37 PM
The UV inks are an exciting development. UV-cure technology seems like near-magic to me.
The best UV cured product I have seen is the lacquer finishes for guitars. Traditionally, they would be sprayed then left for several weeks before final finishing. Now they can be worked on less than an hour after application.
Yeah, there are more levels to "surface treatment" than just treated or not treated. Photographic emulsion seems to be very demanding and needs a particularly "good" surface treatment. Some products that are treated for inks, may not work for emulsion. Heck, they don't even work with all inks...
So, for example, there is polyester sheet available that is corona treated at factory to make printing possible. So it seems that the corona treatment is not completely volatile. It remains good enough for most inks, but not good enough for emulsion (and some inks).
But given that 3M product, it's probably easiest to just buy and use it. Do you know of any retailers who sell those with international shipping?
05-10-2012, 05:11 PM
You might start here (??, of course.)
05-10-2012, 06:15 PM
For photographic use, corona discharge is considered unusable after about 48 hours. I'm giving our normal guidelines at EK. Therefore I would bombard either in-line (ILEB) or I would schedule bombardment 24 hours before my coating time.
05-11-2012, 11:23 AM
Any pointers or links to read about it?
US 4076772 describes a method of coating gelatin on PMMA (= "plexi"): "A poly(methyl methacrylate) sheet is coated with nitrocellulose, the nitrocellulose is denitrated, and a gelatin solution is applied (...)."
Ammonium sulfide is used for denitration.
05-11-2012, 11:24 AM
The UV inks are an exciting development. UV-cure technology seems like near-magic to me. I use a UV-curable adhesive to make glass emulsion wells. [/I]
That's a very interesting.
As an aside, photopolymers (hydrophilic or hydrophobic) based on free radical polymerization, may actually provide improved adherence to a great many kinds of substrates. Free radical formation seems to be the principal reason why corona treatment "works".
05-12-2012, 11:25 AM
For the moment I've only been playing around with setting and hardening gelatin, played with the idea of gelatin on it's own, but it tears way too easily.
Making crude cellulose acetate, and dissolving and setting and evaporating it is fairly simple process, you can make whatever thickness you want, but you can't exactly make a roll that way, but you could build a very large trough, or long trough with a sheet of window glass. You can make even better acetates with the addition of acetic anhydride.
Eventually I would like to try my hand at coat with an array of fine spray nozzles over a moving transport through a simple machine, but I don't know yet.
05-12-2012, 01:27 PM
That's interesting, the idea of using gelatin or some other colloid as the base (I think collodion's been used in the past too).
The idea of casting one's own base is zany but wonderful. I'm glad someone's thinking about it.
I wonder if there's some modern polymer that you could "cast" in a similar way to cellulose acetate, with better properties.
05-12-2012, 02:35 PM
Mark Osterman teaches and demonstrates the making of film support in one of his workshops. It is not all that hard.
05-12-2012, 03:35 PM
IIRC, that demo was with nitrocelluose film support.
I have a demo of TAC (CTA) being made and hand coated.
05-13-2012, 11:34 PM
I didn't know Mark did that, is it indeed nitrocellulose? It makes sense he'd prefer something flammable... :laugh:
Ron, do you recall if Jim had investigated this 3M support for his non-staining base?
Would love to know how to make cellulose triacetate!
05-14-2012, 01:30 PM
IDK which type of support Mark made. You might ask him. Same for Jim Browning. He tried a number of supports before he settled on the one he did.
05-17-2012, 02:47 PM
I just wanted to ask you a bit more about the 3M films. This is really a great epiphany; and I think that although you mentioned them on the Light Farm that this is the first place where they're mentioend by specific product name(?).
How would you compare the subbing to DuPont 583 (PF melinex)? Both will be destroyed with pre-wetting of any kind but DuPonts is very resistant to abrasion and even oily fingers (trust me, I tested it... after eating fried chicken... ;)). How about the 3M stuff?
Also, what size did you get it in if you don't mind me asking? Is it in a roll, or sheets, how long and how wide? Did that company offer any kind of custom slitting or size options? I'm just rather curious about all these bits of minutiae.
Thanks again for bringing this to everyon'e attention; I'm quite excited by it.
edit: Here is a list (http://solutions.3m.com/wps/portal/3M/en_US/oem/MedicalOEM/product-info/where-to-buy/?PC_7_RJH9U5230GQL00IOQBUJJG3AP4000000_assetId=111 4286574869)of potential suppliers.
05-18-2012, 10:24 AM
Actually, I think that poor scratch resistance of subbed films (both 3M and Dupont) are the material's Achilles heel. The Dupont film that The Formulary sells has minute scratches. They're almost impossible to avoid. I'm getting much better at handling film, but (so far) it's a guarantee I'll end up with a scratch somewhere in any given batch of finished film -- usually from the final cutting-to-format stage. I'm pretty religious about wearing cotton gloves, so I can't speak to grease resistance. I can tell you that you don't want to sneeze on the stuff :whistling:.
The good news is that the scratches are essentially microscopic. (More info: http://www.thelightfarm.com/cgi-bin/htmlgen.py?content=28Nov2011 )
One issue that I'm still working out is that the 3M film doesn't seem to hold dry emulsion as well as the Dupont if the coating temperature is too high. I've got the right temp for my emulsion figured out, but I'm not motivated to test, test, test all parameters, just to obsessively blog, so I'm hoping others will join the Light Farm 'research team' and share their findings. (A girl can always hope.)
The 3M vendors I talked with all would do custom cuts for a price. I never asked about sheets. I think the film is only available in rolls. I was able -- and quite happy-- to take remnant end pieces in various widths -- for both the thin and thick films. I got a great deal that way. My only requirement was that no one roll weighed more than 50 pounds or was wider than 36 inches.
You're right about hydrophilic subbed PET being a game-changer. Seriously, there is now absolutely nothing standing in the way of really, really good diy film, plates, and paper (except of course, the exact same things 'standing in the way' of all non-instant, non-digital photography -- enough time and space to create.)