nontoxicprint

Nontoxic Printmaking, Safe Painting & Printed Art


Intaglio Type
Photopolymer Printmaking 






David J Reed, 'Ah Sake', one of the first four color intaglio prints using ImagOn film (RIT research)



  





A breakthrough in intaglio printmaking

Traditional intaglio printmaking cannot produce the kind of full photographic color achieved in other print media. In the year 2000 KEITH HOWARD and his colleague David Jay Reed set out to change that fact. Through their collaboration, a number of Intaglio Type techniques were developed that bring photographic realism to the intaglio medium - in full, glorious color. In a similar manner to screenprinting or offset, a set of primary colored plates is made from color separations then overprinted, on the same sheet of paper, to produce the full spectrum of colors. The fact that these prints are made in the intaglio manner gives a tremendous richness and saturation to the resulting image.

Keith Howard, Adam, 2004
high resolution Intaglio Type
,








The NEW Color Intaglio Type

Keith Howard's new full color photopolymer process involves the use of digital halftones made on an inkjet printer, thin transparent PETG plates that serve as the matrix for ImagOn film, and crucially, a new method of registering plates through the inverse placement of the plate on the press bed. The fact that the plates are transparent allows for the perfect sequential alignment that is required by a multi-plate project in full color. The result is a stunning new intaglio aesthetic.

Adam Worth, RIT
large-scale color Intaglio Type
,
click on image for close up of this print





















Susan Groce 'Invasive Species', Intaglio Type Assemblage, click to enlarge





A quick guide to photopolymer printmaking

For more detail go to the
BEGINNERS COMPENDIUM
and
INTAGLIO MANUAL


and the websites of the following experts

       
        Keith Howard

        Elizabeth Dove
        Henrik Boegh
        Dan Welden
        Kevin Haas


Keith Howard,
Munch's Scream Missing, 2006
4 Colour Intaglio Type 32 x 48 inch (hand printed with 8 plates)



The Film

Most printmaking suppliers stock
photopolymer film such as ImagOn and ZAcryl film (see PRINTMAKING RESOURCES). You may also want to research your own source of circuit board film - it may well be suitable for the process.

Artwork

Use any kind of black or tonal artwork created on a clear transparency. A wide range of positives is suitable for the process: use a photocopier, inkjet printer or laser printer for reprographic stencils. The more opaque the marks the better, you may double up copies to obtain a better transparency. Follow expert instructions on how to make high definition transparencies (websites listed at the bottom of the page). Alternatively paint and draw on Mylar using waterproof felt-tip pens, crayons, acrylic, or toner washes.





Karrie Swanson and a team of RIT grad students collaboratively printing sets of full color intaglio type prints (plate inversion method) 










click here for a slide show
















        METHOD

        Prepare the plate as follows:
   

  1. Evenly sand a metal plate/ thin PETG or Plexi plate, or similar
  2. De-grease the plate with dish soap or Comet
  3. Rinse well then dry
  4. Cut a piece of film slightly larger than the plate
  5. Peel back the soft layer of clear Mylar (use a piece of sticky tape as an aid)
  6. To DRY laminate, sandwich the plate and film (emulsion side down) between sheets of newsprint, cover with opaque smooth paper, and run through the press, preferably twice. To WET laminate (which gives the best results) immerse the plate and film in a water bath, then place onto a glass surface and squeegee from the centre of the plate outwards. 
  7. The emulsion is heat and pressure sensitive so heat the plate now with a hairdryer or heat gun on the low setting or use a lightfast drying cabinet
  8. Immerse the plate and film in a water bath then squeegee for the best lamination
  9. Trim the plate edges with a blade or scissors

Bernice Cross printing a four color Intaglio Type project






        METHOD

        Expose the plate as follows:

        Aquatint screen exposure (non-etch)
  1. Turn on the Exposure Unit.
  2. Place the plate with the emulsion facing the light source on the bed
  3. Cover with a suitable random dot aquatint screen (see AQUATINT SCREEN)
  4. Expose for about 10 to 15 Light Units; this should yield a good black. If in doubt use the Howard testing method for exact determination of the screen exposure (The Contemporary Printmaker, Write Cross Press 2003).
  5. Close the lid of the exposure unit and engage the vacuum pump
  6. Press start to expose
The light exposure will now convert the semi-liquid monomers of the acrylic polymer emulsion into hard plastic. All areas that are covered by marks will stay soluble and will wash away during the development process. In a sense the process equates to traditional acid etching of a metal plate, only in this instance it is the polymer emulsion that is being eroded to create the intaglio printing surface.


Image Exposure
After following the steps outlined above, remove the aquatint screen and repeat the procedure at a slightly lower setting for your artwork (about 7 to 10 Light Units tends to work well). A homemade set up using photo floods would require longer exposure times, say 5 minutes for the screen and 3 minutes for the image.


Halftone
If your transparency is a halftone made especially for this process no aquatint screen exposure is required (about 7 to 10 Light Units tends to work well).
       


        METHOD

        Develop the plate as follows:


The standard developer for photopolymer films consists of a mild solution of sodium carbonate in water.

  1. Make up the developer using a ratio of 10g of sodium carbonate crystals per 1 liter of water - this has been successful in many print shops. Always make sure there is ample developer in the bath, say 5 liters or 1.5 gallons. This ensures that plates develop well. Plates tend to be under-developed if there is an insufficient volume of developer in relation to the surface of the plate. Follow Keith Howard's advice on making up a developer and testing the water for perfect results.
  2. Place the plate face-up in the bath and develop for 9 minutes. If you decide to agitate the plate or brush it with a sponge development will be quicker but more intuitive. A slightly under-developed plate can always be proof printed and then redeveloped for perfect results.
  3. After 9 minutes rinse the plate with water, then spray with a mild vinegar solution to stop development and stabilize the plate.
  4. Now, quickly blot the plate then blow dry it until the plate surface feels hard





        METHOD

        Print the plate as follows:                                           click on image for a slide show
  1. Bevel the plate (very thin plates may not require bevelling)
  2. Print the plate in the usual intaglio manner using oil-based etching ink or the new Akua waterbased intaglio inks (these are easier to wipe). After squeegeeing on the ink use scrim (tarlatan) to remove the bulk of the ink. Then do most of your wiping with newsprint or yellow pages, using a flat wiping action. All or most of the ink should be removed from the surface making the image fully visible against the blue polymer surface. Make sure you clean the underside of the plate as well the edges to ensure a clean print.
          RIT grad students registering an ImagOn plate




NEW METHOD

Keith Howard's new "upside-down" method of printing transparent plates using waterbased ink, allows for perfectly registered full color intaglio prints (also see PERFECT REGISTRATION for pin registration). Keith Howard gives a guide to his 4 Color process in a dedicated pdf fact sheet. Go to The AKUA web site for details: click: http://www.waterbasedinks.com/newsletter/articles . You will find the guide as a pdf download under 'Articles'.







ImagOn (HD) TM, DuPont


A Note about using ImagOnHD

ImagOnHD represents the latest generation of photopolymer film designed to yield higher definition due to its transparent green emulsion.



ImagOnHD functions a little differently to other, older ImagOn films. The instructions for using other ImagOn films outlined in "Non-Toxic Intaglio Printmaking" will not work properly for this new film. The most essential element for successful use of ImagOnHD is to follow the instructions in Keith Howard's manual, The Contemporary Printmaker. This new film has basically the same instructions as for ImagOn ULTRA rapid. Before commencing, it is very important to test your soda ash developer, as outlined in Keith's book.

With ImagOnHD the emulsion is no longer blue but transparent green. Always make an exposure test. To lighten an image INCREASE exposure. To darken DECREASE exposure. On industrial exposure units always choose the lowest intensity lamp setting or filter the lamp with neutral density filters (#210) from www.leefilters.com. Ideally the Aquatint Screen exposure should be around 20 seconds. This is extremely important for achieving optimum results.

* ImagOnHD can also be dry laminated by removing the peel-back film layer: place the emulsion face up on to a sheet of pristine Plexiglas, then lay a plate on top and run through the press. Heat cure the plate as normal. ALWAYS mix ImagOn developer and LAMINATE the ImagOn to the plate the day before exposing and leave covered.

* ImagOnHD has a transparent green color making it easy to register 4 color Inversion Intaglio-Type plates. This transparent quality of the plate makes upside down plate sequence printing easier.

* ImagOnHD has the same developing process with a 9 minute still development in a 10gm soda ash to 1 liter of water solution BUT your image may benefit by an additional 1 minute gloved hand agitation using a soft dish-washing sponge.

* The ImagOnHD plate is fixed with white vinegar and washed with water as with the old film.

* Do not store the film in temperatures over 75 degrees F.

If you have any technical problems email: KeithHoward@KeithHoward.org

 


Photopolymer Film: Variations and Purchasing Options



The following Suppliers carry ImagOn dry Photopolymer film recommended by Keith Howard


Graphic Chemical, US

Daniel Smith, US

Renaissance Graphics Arts, US

Takach Press Fine Art Printmaking, US

Polymetaal, NL

Oktogon, D

Parkers Fine Art,  AU



    Identify Damaged ImagOn Film (pdf fact sheet)



There are other kinds of dry Photopolymer film that also work for Photopolymer Printmaking; often these are adapted from their original use in the printed circuit board industry as etching resists. All film are sandwiched between two layers of clear mylar and expose with UV light, and all films develop in a soda ash developing solution. Developing times, exposure times, film thickness and contrast / tonal range may vary from product to product. The thick variants of film are ideal for non-etch printing, while the thin varieties are best suited as a photo etching resist (such as Puretch).



 Z-Acryl 

Photopolymerfilm, UK  (Photec)

Cape Fear Press, US  (Puretch)

GrafiskEksperimentarium, DK   (DK3)



Photopolymer Film vs Solarplate

Some print studios and artists prefer the use of ready made photopolymer plates from the printing industry over the use of dry film. The process is very straightforward as the user does not have to go through the plate making steps. The quality of the photo-reprographic intaglio prints made by these plates can be outstanding. This is due to the thickness of the polymer emulsion and the high tonal range and fine detail facilitated by these ready made plates, especially if used with a good aquatint screen or a high quality halftone. However, plates tend to be expensive, and creatively the process is somewhat more limited than dry film photopolymer printmaking. First pioneered by Eli Poinsang in Denmark, the method was popularized by Dan Welden with his Solarplate process. Click here for details.





Safety Aspects of Photopolymer Films and Plates



Dry photopolymer films are considered a comparatively safe family of materials.

There are some safety considerations which should be taken into account before use.

The company DuPont gives detailed information on the safety

of their photopolymer films in their safety sheet TB-9944;

key extracts from the text are quoted below.











Currently, there are significant concerns regarding the safety claims of ready-made industrial photopolymer plate. These plates are known as flexographic plates in the printing industry. (FLEXOGRAPHY). Such photopolymer relief plates are not to be confused with dry film that develops in sodium carbonate.

There may also be hidden dangers in these industrial photopolymer films from the PCB industry, and regarding their use, that are not yet fully understood or documented. For more details on Solarplate,
see: Solarplate.  The company DuPont who make ImagOn, give a relatively credible and detailed account of the safety of their films, see below:
 


Handling Procedures for DuPont Photopolymer Films TB-9944

(click for full pdf tech sheet)

 




Handling Procedures for Photopolymer Films (DuPont)


Incidence of Health Effects: ‘Numerous operators worldwide have handled DuPont photopolymer films daily for forty years, but DuPont has received only a few enquiries per year on health effects. Although not every instance of related health effects is reported, the records show that few cases occur.'


Health effects of Acrylates. DuPont as well as other manufacturers formulate photopolymer films with multifunctional acrylate monomers. Historical and toxicological information has shown that that multifunctional acrylate monomers can produce potential health effects…Overexposure to the acrylates in the films can have these known effects: Respiratory irritation / Skin Irritation / Skin sensitization

 ‘Casual contact does not appear to cause monomers to be transferred to the skin and absorbed in sufficient quantities to cause skin irritation...’

Respiratory Effects

Heating of photopolymer films generates vapors, and the condensate resulting from these vapors, is responsible for virtually all reported health effects. To prevent exposure, equipment that heats the film must have an exhaust system that will remove vapors from the workplace and avoid the formulation of vapor condensate. Inhaling vapors from heated film may result in dryness and irritation of the respiratory tract. This is especially true if films are heated above their normal use temperature. More harmful effects are possible if normal safety precautions (e.g. laminator ventilation) are totally disregarded.

 

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Click for the 'Grabado y Edicion' article Keith Howard: Llego la revolucion (2008)
       Or visit the publication website: www.grabadoyedicion.com

Click for the 'Grabado y Edicion' article fotograbado con film fotopolimero (2008)
       Or visit the publication website: www.grabadoyedicion.com


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Intaglio Type Prints



























details of 4 Color Intaglio Type Prints by Keith Howard











                                                                                                     

Marchelo Vera, digitally manipulated 4 Color Intaglio Type, RIT grad program, 2011











Liam Murtaugh
assemblage made from color Intaglio Type prints
2007



Victoria Delaney
Pier
photopolymer prints on primed canvas
University of Chester degree show
2005








Joan Hausrath
Intaglio Type print
made during the 'Innovative Intaglio'
International Summer School
Gracefield Arts Center, UK











































Eric Coleman

Americana 1
four color etched photopolymer print








Mike Bolam
Intaglio Type Print made from a laser copy





Ewa Carlsson
B+W Intaglio Type Print made using a halftone created on an inkjet printer







Keith Howard exposing an ImagOn plate in the sun

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