In order to have photographic images in my final book edition ‘Hazel House’ I decided I wanted to print them as photo polymer etchings. The process shares some similarities to screen-printing and etching. The course was at East London Printmakers (ELP), run over 3 weeks on Wednesdays, it was a enjoyable experience getting to know our large group and learn about everyone’s varied disciplines: photographers, an illustrator, architects, printmakers and graphic designers, we were all looking to use the process for a diverse array of projects.
The plates that we used were polymer-plated steel.
We learnt two processes:
- Intaglio – this is printing where the areas that hold ink and print are a recessed level. This type of printing holds more detail and works really well for tonal images such as fine detailed photography. You will need KM73 photopolymer plates for this process; these are available from Intaglio Printmaker (for artists based in London).
- Relief – this is printing where the ink is rolled and prints from the raised surface of the plate. This type of printing is good for graphic images where there is bold contrast. You will need KM95 photopolymer plates for this process; these are available from Intaglio Printmaker (for artists based in London).
Because of the messy nature of the printing process I have taken fewer photos of this course, but below I explain each process:
The Intaglio Process:
The process starts by making a positive. A positive is an image printed digitally onto a transparent film like acetate. To begin: a digital image is manipulated on Photoshop to get the required levels of contrast and tonal detail, cropped and made print ready. Always use non-destructive editing, as you may wish to use the original image for other purposes. Make adjustments to the levels in layers. It is then printed onto Folex laser film from a printer. The drawback of using your average laser printer is that sometimes you get streaky lines through the image. Depending on the type of image you want and suitability, you may wish to get a professional positive made by image setter (you can find these online). You can also use True Grain to make a positive, which you can draw directly onto.
Once you have your positive, you unwrap your polymer plate (which is light sensitive), remove the protective film and place it on top of the UV exposure machine bed. Making sure the glass is clean first. The machine at ELP takes 10mins to warm up. Place the aqua tint screen over the top of the plate (ink side face down), and close the glass lid clamps. The maximum plate size that will fit in the machine is A2, or several plates can be exposed at once. Engage the vacuum button, wait until all the air between the plate and the screen has been removed, and there are no air bubbles. Using Two hands on the handles flip the lid of the machine, so the plate can be exposed to the UV light.
Set the exposure time, half power for mid-tones, if your image has high contrast, then use full power. Real time is seconds / integrator (units) – this compensates for the age of the lamp, which when new will be stronger, and overtime will be dimmer, and exposures need to be longer. At ELP we were setting the timer to 800 half power. Press ‘run’ wait for the buzzer, then press buzzer reset when it goes off, flip the lid, turn vacuum off, unclamp and open the lid. Roll up the aquatint and put away. Next place the ‘positive’ ink side down on the polymer plate (carefully maintaining boarders, and not pressing into the plate as the polymer is soft until baked / hardened by exposure to UV). Close the glass lid, clamp, vacuum, spin the lid and reset the timer to 800, then run.
In the acid room fill a tray with water and mixing hot/cold get the temperature to 20/25 degrees. Once the buzzer has gone off and you have retrieved the plate/s take it to the acid room, and set a timer for 3mins. Submerge the plate in the water bath and with a new sponge carefully systematically wipe over the polymer side of the plate until the picture emerges. The areas that were covered by darker areas of the positive image have not hardened by the UV light and remain soft therefore they wash away. If the plate still feels slimy under the finger then re-wash as the polymer is still coming away. Very fine areas are quite fragile, so you have to be delicate. Blot the plate with newsprint, and quickly dry with a hairdryer.
Harden the plate on the exposure machine, attach a little loop of brown tape to the underside of the plate and attach to the bed of the machine, close the lid without the need to vacuum, flip the lid and run. Alternatively you can leave the plate on a sunny windowsill for an hour or so.
You can only use oil-based inks for this process, and at ELP they use vegetable oil for cleaning, as this is more environmentally friendly.
At this point you may wish to trim your plate on the guillotine. Use a burnishing tool to file off the cut edge burs, and the other edges where necessary. This is important because your plate will emboss the paper you print on, and you aim for a nice square edge, and more importantly if it is a very sharp edge it will cut the blankets on the presses and these are very expensive to replace.
Now for inking the plates: In advance of printing prepare your paper: cut or tear your paper to size and cut down pieces of newsprint larger than your plate / paper. When working in the inking area put gloves on and be ready to take these on/off regularly, this saves you time washing you hands which is very slow with oil-based inks, and protects the clean printing presses and your paper.
On a glass-covered work surface squeeze out some ink and some extender, scraping excess off the nozzle with an ink knife. Mix together on the glass. Take a rubber squeegee and dip the tapered edge of it into the ink. Holding your plate in the palm of your hand with it half hanging off the edge of the workbench, evenly apply the ink methodically in stripes in one direction (top-bottom) then the other direction (side-side). Take a piece of scrim and make it into a fluffy ball with no creases. Holding the plate half off the bench, use circular motions to press/rub in small sections on the plate, until you have done this across the surface of the plate. Next using linear wiping motions wipe the plate. Use tissue paper to wipe the plate, keeping the tissue paper and fingers flat and parallel to the plate. Take a lint-free rag and wrap around forefinger without creases and wipe plate until the raised areas appear clean. Using whiting wipe over edges of the plate. Your plate is ready to print.
On the press the stack should be: 1. Acetate, 2. Plate, 3. Paper, 4. Tissue paper
In advance of inking your plate take a piece of acetate larger than you printing paper and place over the paper, using a Sharpie permanent pen, draw around the paper using a ruler. Now draw two diagonal lines from corner-to-corner of this square or rectangle, to form an ‘x’, this gives you a marker for the centre of the paper. Remove the paper from under the acetate. Now place the acetate over your plate positioning the plate in relation to the paper guides and centre. When you are happy with the position mark the corners of the plate on the acetate with dots. Remove the plate and join the dots with a ruler. Write ‘This Way Up’ in reverse. This is you printing guide when placing everything on the press. You can have multiple paper guides on the one sheet. Remember when using the guide to have the ink side face down on the press to avoid ink transfer.
Because the paper needs to press into the indentations of the plate that contain the ink, you soak the paper in a water bath for 5 mins. Before putting it in the water bath mark small initials in a corner on the front or back of the paper, as it is difficult to differentiate when the paper is wet. From doing this course I learnt that I made a painting in 2013 on the wrong side of Fabriano paper, this is a common mistake, as I noticed a drawing in the Jerwood Drawing Prize was also on the wrong side of the paper. On Fabriano paper the name is embossed on the reverse of the paper, rather than the front, so on a framed print where you see a deckle edge the brand name Fabriano should be backwards if the artist has used the paper correctly, other brands such as Sommerset have their logo on the front side of the paper.
When you are ready to print and the acetate and plate are on the press, remove a piece of soaked paper and place it on a vertical perspex panel and squeegee excess water out. Place the paper between two towels and using a kitchen type roller, roll over the towels. Removing moisture from the paper is important to protect the blankets.
Place the paper on top of the plate, cover with a sheet of tissue paper. The blankets should already have their end tucked into the press, and should be in this order: Thick, Med, Thin. Flop the blankets over the tissue paper and turn the large press wheel with two hands. Keep turning until the blankets are almost all the way through, but never roll them all the way. Leave the wheel handle at the bottom at the end of the cycle. Flop the blankets over, and carefully peel the paper off the plate. Dry the paper on drying boards with more tissue paper on top. The prints should be left for 1 week to dry, but can be stacked between boards. Use an ink knife to lift the plate off the acetate, and clean the acetate with a rag. Depending on the tone of the print you have made, you may want to do a secondary print without re-inking, or you may wish to re-ink the plate.
The Relief Process:
This process is good for images with less detail. There is no Aquatint stage to the process. There is more to wash away of the polymer, and the exposure time is less.
While you wait for the UV exposure machine to warm up, for the bulb to turn from white to purple, check the glass lid is clean a streak-free. When looking at your positive, the black part of the image will wash out, because this area will not have been exposed to light. For relief printing you use full power, rather than half power on the UV exposure machine. While your plate is exposing prepare your water bath. Once the plate is exposed, remove from the machine and place in a water bath wiping the plate with a clean sponge and a brush to work into finer areas. You don’t need to time this washing as it will vary depending on the plate, just continue washing until it doesn’t feel slimy. Dry the plate with a hairdryer. Dust the plate with a tiny sprinkle of talc and work into the surface plate if it is sticky, put a looped of brown tape on the reverse of the plate and stick to the bed of the machine and harden it with two lots of 800.The plate is a negative, so any text should be visible in reverse on it. Once hardened you may wish to trim your plate on the guillotine.
When you ink your relief plate it is more like doing lino printing, so you are loading the ink onto the plate using a roller. Soak paper in a water bath for 10 mins, squeegee, blot and roll between towels. Place your acetate guide and plate on the middle of the bed of the press. Place the face of the paper onto the inked plate, cover with tissue paper, flop the blankets over, and run through the press. If your print is too light, then for the next print you can add pressure if needed via the bolts on the top of the press.
You can use relief plates for blind embossing. On this course I made a Male / Female Toilet sign image from a series I am working on, and I was more satisfied with the blind embossed images over the inked images. I think I now have a secondary artist book edition to work on right after the first. Other people on the course did really beautiful images using different coloured inks, and mixing intaglio and relief printing using multiple plates. There is a lot of scope to experiment with both of these processes.
On the final week I made an A5 plate and made several Intaglio prints of one of the most important images from the Hazel House series, and I was really pleased with the level of detail and tonal range of the image. I am looking forward to the open access sessions at both ELP and LCBA that this wonderful a-n Professional Development Grant has afforded me. But before any more printing or bookmaking it’s time for me to plan my layout for the ‘Hazel House’ book.
What an adventure…
