Laminating, exposing and developing photopolymer plate 

Thanks Mateusz! Very kind of you! You need a positive because you need to harden the areas on the polymer plate that will become the light areas with little/no ink in the final print. If you use a classic film, negative, you'll encounter two issues: (1) your final print will be a negative as well. (2) film negatives don't have a screen, so dark areas will not hold ink. To solve this, you'll have to invert your negatives; if you want to do this in the darkroom, you could make a positive using e.g. an enlarger and print your negative onto film (something like xray film might work, or a regular ortho B&W film) and expose the polymer twice: once with the negative and once with a stochastic screen.

This material is sensitive only to UV light, so any lighting that does not have a UV component in it will work.

Many thanks Roberto for your kind remarks. The reason why a separate halftone screen is not used at all is because the dot pattern of the inkjet printed positive transparency serves as the screen. This eliminates the necessity of a separate screen. Of course, a working method with both an inkjet printed positive plus a separate halftone screen would also be feasible, but I did not test this.

@@koraks9939 if i want to start to print with this technique, what i need: press (i just have it), and?

@@robertozamperoni4437 The most essential things are a decent inkjet printer and transparencies, the UV-sensitive laminate (e.g. DK3), a UV light source, contact printing frame, intaglio printing inks and obviously paper suited for intaglio/etching. But most importantly: a lot of dedication, patience and perseverance!

@@koraks9939 ok, about printer, transparencies, contact frame printing, uv light, i just have all because i just print with platinum palladium technique. About paper and ink i must buy it, which paper do you suggest? I have Arches Platine 300gr, can i use it?

@@robertozamperoni4437 Sounds like you're pretty much set. If you can make Pt/Pd prints with digital negatives, you will be able to work out the required curves for this process as well, so that'll save you some time. In terms of paper, I used to use papers I could get here locally but that aren't available internationally as far as I know. It doesn't matter though; any etching paper can be used. I'm not sure Arches Platine will be the best choice; it will work, but I can't guarantee it will work very well. Just give it a try. Otherwise just pay a visit to the nearest art supplies store and pick up some papers intended for etching. You may find that there are papers that are significantly cheaper than Arches Platine that work even beter for this process.

Thank you for your kind words! It's nice to see you're about to pick up printmaking once again, I hope you succeed! I haven't tried photopolymer in combination with copper plates, but I know of others who worked this way and the results were very good. So it can be done, that's for sure. As to exposure: the nail hardening apparatus may actually work fine for smaller plates. An affordable alternative is a (second hand) face tanner placed at a reasonable distance (let's say 1-2ft) from the plate. The photopolymer doesn't require very intensive exposure, so there's no need for the very high-powered exposure units you'd want for some other printmaking processes (e.g. carbon transfer or salted paper prints). The main concern is collimation; e.g. a face tanner is essentially a rather diffuse light source, and combined with the thickness of the photopolymer film, this makes it hard to accurately expose very fine patterns. Hence my recommendation to allow for considerable distance between the light source and the plate, so that the light is at least collimated somewhat. A true point-source would be preferable - something like a single high-power UV led at a fair distance from the plate should work nicely. But that would probably push you into DIY territory (unless perhaps you can find someone willing to fashion something for you).

@@koraks9939 thank you so much! I am inspired to give this a try!!

Is this in the print? I have had this inversion happen with plates that didn't have a good intaglio pattern. The most apparent issue was so-called 'foul biting' - the dark areas not having enough intaglio pattern to hold the ink. This leads to a partial inversion of the image that is very similar to solarization in silver gelatin prints. The problem in that case can be traced back to exposure or development of the photopolymer, such as insufficient exposure of the photopolymer, too much diffusion of the light source and/or overdevelopment of the photopolymer plate.

@@koraks9939 No its not in the print. I haven’t printed yet. Its on the plate. All the dark areas are shiny and vice versa. I’m gonna print it tomorrow. But it looks like all the dark area are gonna light and all the light areas are gonna be dark. The prints I did before didn’t have this problem, it was lines, but this is more tones, not line, more light and shade.

@@juljos9343 Ah, that's interesting. I don't recognize the issue off the bat, but printing the plate will probably make the situation clearer. What I also used to do was inspect a freshly made plate with a loupe. The pits and valleys are pretty easy to see under the right light, and with a little experience, you can figure out if a plate is likely to print well, or what the possible causes for any problems are.

Can you give some more information on what problems you're running into? The soda concentration is not very critical, as long as you use the same concentration for all your plate development and adjust the development procedure to it.

@@koraks9939 The problem is, I can't get the same concentration every time. Every time I make a new mix its slightly different. I have no way of measuring it. Anyway Once that's done, I don't know if its right until I go to the inking part, then I can see where the ink will take or not.

@@juljos9343 ah well, then the answer is simple: get a scale and a graduate. Both can be had for little money. Very high accuracy isn't required, so a cheap digital scale from the internet and a plastic graduate from the store will do fine.

For the development of the plate, also other alkaline solutions may work, e.g. sodium/potassium sulfite, hydroxide, bicarbonate, borax...but I didn't try any of these and you'd have to experimentally work out the appropriate solution strength and development time.

MH D no, but you need to make sure there is no UV light in the room you handle the material in. So daylight is not a good idea; most artificial light and particularly incandescent light is fine.

Koraks Thank you for answering my question.I was working in dark room for screen printing using a yallow light bulb and since is new for me .I think it would be the same process then .I really appreciate your advice .Thank you again.

Monique Lefebvre www.koraks.nl features some of my work, but I don't update it regularly.

Sodium carbonate; I used decahydrate for this, which is the most common form of cleaning soda sold in supermarkets etc. But e.g. monohydrate will work just as well, but you need less of it.

@@koraks9939 I've been to my supermarket I've seen the soda carbonate crystal powder. How is it mixed with water. How much water and how much powder? Whats the ratio?

@@juljos9343 I think I used 10 grams of crystal soda per liter of water. You can scale that up or down according to how much of the stuff you need to cover the plates you're using in a tray. So if you only want to make e.g. 500ml, 5g of soda will do. PS: the exact ratio is not all that critical; 10g/1l is a 1% ratio, but e.g. a 1.5% ratio would work as well, with a shorter development time. The important thing is to be consistent. So always use the exact same ratio!

Thank you. I'll b trying it soon.

I think this unit is something like 50W or 60W. You don't need a very strong light source for photopolymer; it's quite light-sensitive (at least to UV). I would recommend using a point source though, as diffused light doesn't work optimally. Collimated light is best to image the fine detail of the dot pattern that is required to generate good blacks.

thanks man!

what u mean with a point source ? like a uv flashlight?

how to u colimate?

Any light source where the light originates from a single point. If you look at a light source consisting of an array of fluorescent tubes, you effectively have a fairly big surface that emits light. The result is that the light goes in all directions. The light rays originating from a point source, especially at a larger distance (think of the sun), are parallel to each other ('collimated'). The idea behind the use of a point source, or rather collimated light, is that it makes it possible to image very tiny dots with great sharpness, which is of course essential for intaglio work.

No, I haven't had this problem. You don't inadvertently remove the top protective film, do you? DK3 is in essence a sandwich of 3 layers; the bottom layer you remove so that the film can be laminated to the support. Don't remove the top protective layer at this point! Expose the plate, and only then, before developing it, remove the protective top layer.

Koraks i see, yes i do, I thought it was necessary to be able to obtain maximum detail. That explains it! So you always keep the protective film on until development?