USING DRY COPIER TONERS IN PLACE OF TRADITIONAL LITHOGRAPHIC GREASE TUSCHE
A new lithographic drawing technique developed by Nik Semenoff in 1985
For 200 years lithographic artists and printers have used grease based materials to put their images on stone and metal plate. Although this material has been responsible for great works of art when used with crayon, wash tints produced with traditional grease tusche has been a problem from the earliest days. This is regrettable as washes can be one of the most subtle of graphic techniques, but not always practiced because of the difficulty of printing the plates. Even in cooperation with an experienced printer, one must not expect all of the half-tones to come out with their correct tonal value in the impression. If for any reason the artist has reworked the wash before it has dried, then the out come of the print is unsure.
Grease is colorless and so is mixed with lampblack to make the drawing visible. Because of the great affinity of the drawing surface to grease, the clear grease portion of the wash could easily become attached to the plate without being noticed until the proofing stage. Prints then will usually be much darker than the drawing. Strong etches could produce a cleaner and lighter printing plate but at the expense of the fine tints. The image becomes contrasty in these cases. In fact all light tints are susceptible to burning even with the weakest etches and need special treatment. Other areas that are dense would have a tendency to fill in as the pressure of the ink roller and printing process overcome the less desensitized region directly next to the greasy ink. This is caused by the rejection that grease tusche has on the water based gum etch, preventing the area next to it from getting the full effect of the etch. Although most master printers have found methods that produce acceptable prints, what is needed is a material that would allow the artist to manipulate the image at will with no fear of producing an unprintable plate - yet be simple to use.
The Perfect Tusche
The "perfect" tusche would have the following characteristics:
1/ It would allow for unlimited manipulation of the stone or plate with no effect on the image, until the artist is satisfied with the drawing.
2/ It would be completely removable, with no trace of the image left on the plate.
3/ It would print exactly like the drawing, neither darker nor lighter.
4/ It would be able to stand a strong first etch with good desensitization of the plate. Spot etching not needed.
5/ It would be tough enough to stand rough treatment during processing.
6/ It would be usable with either water or petroleum solvents and would still print exactly as seen. 7/ It would be able to produce many traditional tusche wash effects, plus others not possible with grease.
8/ It could be applied with an airbrush or in heavy washes with no fear of the image filling in during printing.
9/ It would be inexpensive and readily available locally.
10/ It would allow for rapid processing while the artist's ideas are still fresh in their minds.
11/ It would be easy to control and process using standard lithographic materials.
In dry copier toners we have such a material. This modern day product is available from a number of manufacturers and there are copying machines in every community. While differing in some respects, most toners can be used in this new technique after testing them for their characteristics.
About Dry Copier Toners
Dry copier toners have been with us since the mid sixties when Xerox brought out their early copiers. Since then a number of manufacturers have developed their own version of the electrostatic copier, with specific toners for each of their models. Practically all toners are made from about 90% thermo-plastics which are colored with 10% carbon black pigment and are set with infra-red after being transferred to paper. The early systems were not efficient and the toners required higher melting temperatures than what is used in today's models. These early toners tend to be slightly different and all toners should be tested before being use in this technique. Newer toners may contain wax, melting at a lower temperature. My research has shown that these older toners are not affected by white gas, the solvent which makes setting of the image an easy matter. These early toners (and some current materials) I have designated as type A. The newer class of toners are easier to set, being designated as type B. These are my own labels that I have put on these materials so that printers can understand there is a difference.
Each manufacturer has their own formula for toners; Xerox data sheets state that there is no more of a hazard handling their toner than from any dusty materials. Since the only time dry powder is used so as to create dust is in filling a small 4-6 oz. bottle, there is little risk in using this material from a health and safety point of view.
How Toners Would Work As A Tusche
Because toners are non-greasy, they have no affect on the sensitive drawing surface until they are bonded to the plate. For this reason the artist can rework the wash indefinitely until satisfied; the drawing can also be completely removed with a damp sponge and the plate redrawn if need be. This freedom of working gives the artist a feeling of confidence which grease tusche cannot. After the water has evaporated, the toner is bonded to the stone or plate by flooding the surface with a petroleum solvent such as white gas or heating the plate with a heat gun. The white gas does not completely dissolve the powder, only melts it enough to bond it to the plate to become a resist for the desensitizing etch. After the etch has been applied and dried, the toner can be removed with a much stronger solvent such as lacquer thinner and replaced with a standard commercial vinyl lacquer base. From this point on the plate is treated just like a standard grease image.
Testing Toner Powders
There are three basic steps to using toners for lithographic images. The first one is to put the image on the plate using water or solvent medium. The second and most important step is to set or bond the toner particles to the surface of the stone or metal plate. The third is to wash out the toner after etching the plate and make way for a good printing base. With this in mind we have to test what effect different solvents have on the toner you might wish to use.
Because of the different types of toners being manufactured, it is wise to test the effect of different solvents on the one you have selected to use. Secure either a ceramic watercolor slab or a number of small saucers and place a very small amount of powder into each section. Pour enough of each solvent to be tested over the powder to completely wet it and watch the reaction of the toner. You will be looking for one of three different effects of solvent on the toner. The first is for those solvents which have little or no effect on the powder. These fluids are used for doing solvent washes over gummed masks so as not to dissolve the water soluble film. The best fluids in this category are the industrial alcohols such as isopropyl and methyl alcohol, and the various odorless turpentines substitutes sold in hardwares and art stores. Most odorless solvents will change the texture of the B type powder after some time, but usually there is enough time for the artist to complete the wash before the remainder becomes unusable. Some toners are affected by alcohols and produce poor washes. Class A toners can be used with most hydrocarbons for washes as well as with water. Since water is the normal medium, solvent washes may be needed only for some projects.
The next type of solvent is the most important to the process but fortunately easy to come by. To set or bond the B toners to the plate we need a solvent that is not too strong and only melts it enough to adhere it to the surface. By not dissolving in this solvent, the toner particles slightly cohere and settle exactly where they were placed; this means that the tonal relationships will not be upset. The best solvent for this purpose is clean white gas, available from hardwares and sporting stores as camp fuel for stoves and lanterns. This solvent is fast drying and leaves no wax or oils like some other fluids. If any wax is noticed around the edge of the image after the solvent has evaporated, it is easily removed with a bit of isopropyl alcohol and a cotton ball. Isopropyl alcohol can also be put on the image with little fear of lifting the set toner, if time is given for it to harden and not too much pressure is applied to the image. This of course depends on your toner.
The third class of solvent is one which will completely dissolve the powder and remove it from the plate. This action is needed to wash out the image and provide a printing base after the gum etch has been applied. For this solvent I have settled on a mixture of lacquer thinner and acetone as a shop mix. Acetone is not as toxic as other solvents and should be used whenever possible. Because of it's volatile nature, the wash out can be very quick and efficient. A 1:1 mixture seems to work about right in my studio. Many toners can be completely removed with acetone alone and this would be preferable because it is the least toxic solvent.
Many manufacturers' toners will work but they must be tested first to see if they have the characteristics described. Since first starting to use this technique with Xerox 9400 toner, there have been changes to the toner supply as manufacturers improve their products. Type A toners seem to becoming scarce.
Mixing the Tusche
Since most artists are acquainted with working with a water medium, toner powder has to be moistened by some means. Being a fine plastic powder, toner is resistant to wetting with plain water. If, however, a small amount of wetting agent such as Kodak Photo-Flo is added to the water to break the surface tension, the powder is easily moistened. Select a wide mouth jar with about 4-6 ounce capacity (baby food jars are perfect). Fill this about 1/4 full of water into which a few drops of wetting agent are added. If the toner is to be used over a long period of time, add a small amount of fungicide such a Dettol which will prevent the growth of a mold that some powders seem to promote. Next fill the bottle with toner to the 3/4 mark and secure the top. By shaking the container for a few seconds, the powder should be moistened throughout. Small portions of this stock mixture can be diluted with water in a saucer for use in your project. If the mixture should dry up in the jar, simply lift out some with a wet brush as if it were tempera block paint.
Other wetting agents are available; the cheapest being the rinse agents used in automatic dishwashers. Acrylic emulsion flow releaser and dispersant are also very good. Some inexpensive household detergents are also usable as they are capable of producing interesting foam textures on the plate similar to peau de crapaud. Try not to use too much of any wetting agent as they can attack aluminium plates because of their alkaline nature; images on stone would not have this problem. Too much detergent also prevents the toner from bonding to the surface. Because hydrocarbons, odorless turpentine substitute and alcohols have great wetting capability, washes with these need not be premixed.
Drawing the Image
Ordinary brushes are perfect for use with this material. On applying it to a plate, you will notice that it seems gritty and does not go on the surface as does grease tusche; being heavier than water, it tends to sink rather than float like grease. By mixing it with more water, a reticulated wash is easy to achieve. By using a thicker mixture with a coarser brush, perfect brush strokes can be retained on the plate. This brush image is impossible to get with grease tusche. There is no fear that reworking the image will darken the print in the final version of the image, so brushwork can be manipulated more to ones liking. Toner can also be lifted off the surface with textured materials to leave a perfectly printable plate. The border of the plate need not be masked in any way as the excess can be easily removed with a damp sponge to leave a perfectly clean printing border.
Toner Chalks Produce Charcoal Like Images
It is possible to compress the toner powder to produce a soft chalk to be able to draw directly on the plate. These chalks are just as easily removed and manipulated as the wash drawing and can give the artist greater freedom. Because of the softer nature of the chalk, the image is more like a charcoal rather than grease crayon drawing. To compress the toner into chalk form takes a great amount of pressure which requires a strong hydraulic press. The equipment and complexity of manufacturing will not be of interest to most artists and beyond the scope of this paper. To make toner chalks I have had to construct a complicated hydraulic press with various automatic controls to produce chalks of a consistent nature.
Air brushing can be carried out with perfect confidence as the tints will not plug up or be etched away in the light areas. Some air brushes produce a problem because the heavier nature of toner makes it settle in the cup or bottle and not come out as easily. After the water media evaporates, the plate is ready for setting. Dry powder can also be dusted over the plate to produce tints similar to rubbing charcoal. This type of application sometimes produces a darker image than what was envisioned by the artist, depending on the type of toner used and the grain of the plate. While the powder is fragile and can be damaged easily at this point, it can safely be moved around the studio.
Creating Solid Areas
Because of the nature of toners, solids are harder to achieve. The toner does not lie down as smoothly on the plate due to its grittiness and can produce streaks. To produce solid areas it is easier to use plastic emulsions. One can use some of the household floor polishes made from a clear polymer emulsion. I have found Future Acrylic Floor Polish just about perfect for this job. By adding some black Sumi or India ink to the polish, a dark waterproof ink is obtained. This can be applied to the plate by brush or pen and give better results than traditional grease tusche or autographic ink. While this will only produce a solid area, this is what the artist is really after. Only enough black color is needed to see where the plate has been covered. This ink for producing flats can be added to the plate after setting the toner image and the dry ink is easily removed with solutions containing ammonia, if changes are required. Since there need be only a thin film of acrylic plastic to make the solution work, the polish can be thinned to a consistency preferred by the artist.
Setting the Image
There are three possible ways of bonding the toner to the plate of stone. Being a thermo-plastic, heat, like in the Xerox machine can be used. Toner is also fused but fumes of strong solvents such as acetone and lacquer thinner. This is done in a special vapor chamber. The third method is to use a weak solvent such as white gas that just softens the toner particles and allows them to bond to the surface. Because of the nature of toners, setting and etching can take place immediately rather than waiting for the chemical action to take place between the plate and the grease tusche.
The simplest and most effective method of setting the image is to use heat of some form. For metal plates I recommend the use of an ordinary household model paint stripping heat gun. Go over the entire surface very slowly so that each toner particle has a chance to adhere to the surface. There is more than enough heat to set the toner and the warping of the plate is of no concern because all return to their normal flat state when cool.
Another convenient method of setting the image is by flooding the surface with camp fuel, and/or a mixture with stoddard solvent; pouring it gently along one edge and allowing the capillary action to slowly wet the powder. Type B toners can be set efficiently with straight camp fuel as it evaporates quickly. To prevent splashing which could disturb the powder, I suggest that you secure a small container with a good pouring lip and place in it a piece of string which is secured to a weight. A small beaker that will hold about 25 ml. of solvent will handle the average sized plate. With the weight inside the beaker, droop 10-15 cm. of string outside the container. By letting the fluid run slowly down the string, you can introduce the solvent gently to the surface of the plate, preventing any damage from a turbulent flow of liquid. Pour sufficient fluid over the powder to completely wet it. By slightly tilting the plate, you can direct the flow of solvent over the entire surface. Use enough solvent to give it time to bond the toner before it evaporates, but not so much as to become a fire hazard. After all of the image is wet, tip the plate to pour off any remaining fluid on to a piece of paper which can be disposed in a hazardous waste container.
A convenient solvent dispenser can be made from a small plastic bottle that has a flip-up spout. By piercing the top edge of the spout with a needle and inserting a cotton thread with a knot at the end, the container can be closed when not in use.
One should note that if the water has not completely evaporated from the toner before the solvent is applied, then those areas will not bond sufficiently to the plate and will be lost in the processing. By not allowing enough solvent for the job, bonding can also be affected. By using paint thinners (Stoddard solvent) which are much slower to evaporate, artists may get better results with some brands of toners, but be sure to remove any traces of residual oils left by these impure solvents.
If for some reason you are working with class A type of toners, you will then have to set your image with a stronger solvent than white gas, or use heat. The best solvent method that I have found is to put a small amount of stronger solvent into white gas. A small amount of these solvents will only slightly dissolve the toner particles and give much the same effect as plain white gas has on class B toners. For these type A toners, add 5-10% acetone to white gas to get just the right bonding action. The proportion of stronger solvents should be carefully observed, as too much will tend to dissolve out the clear plastic material in the toner and deposit it around the more solid pigment. This can produce a larger dot and darker image than what was intended by the artist. This again depends on the brand of toner so experiment for the particular material you are using.
If you wish to use grease crayon work on the image it should be done after the toner is set. If you try to apply grease images over unset toner you will find that the powder becomes embedded in the crayon and prevents any mark being made on the plate. By setting the toner first, it becomes firm enough to be drawn over. On some images the grease crayon may be applied before the toner wash, but there is risk of water dissolving the crayon and petroleum setting solution leaching out the grease to contaminate the plate, heat would melt the grease, so the fuming method should be used.
If crayon and toner are to be used together to any extent, then a vapor chamber might be a good investment. A tight seal on the vapor chamber keeps solvent fumes to a minimum in the work area. The tight seal and the soldered seams of a proper container allows for pouring a large amount of setting solvent inside, and just replenish it as needed. To hasten the setting process I have found that if I mix about an equal volume of acetone with the lacquer thinner, the toner would bond in 5 minutes or less. My only concern with this method is the explosive nature of the fumes in a closed container. Contact me for plans if need be.
Etching the Plate
Unless grease has been used to create part of the image, there is no need to use talc on a toner image. Because it is non-greasy, toner will not reject the etch from the edge of the printing areas. Toner is also tough and if well adhered to the surface, does not require spot etching for different tonal areas on the plate. Apply your favorite etch over the entire surface with little concern for light or dark areas. I have found that a strong first etch is all that is needed to completely desensitize the plate and I have not used a second etch for much of my work. Buffing down the gum etch is also easy as the toner does not smudge due to its solid nature.
While you may use any good etch formula, I have found one best suited for toner images. Originally developed by Arnold Singer of New York, I have modified it for use with toner. This harsh etch was not recommended for grease tusche washes which it tends to burn out, but gives good desensitization on grease crayon drawings. The formula is as follows:
Gum Arabic 4 oz. 120 ml.
Table Salt 1/2 oz. 14 Gus
Nitric acid (65%) 28 drops 28 drops
Phosphoric acid (85%) 8 drops 8 drops
Isopropyl alcohol 5-10% 5-10%
Water 5-10% 5-10%
Dissolve the salt first in warm gum to make sure all of it is in solution before adding the other chemicals. Apply the etch for only a minute or so and smooth to a thin film. If printing is not to take place for the next two hours, wash off the etch and apply plain gum. To the original formula I have added the isopropyl alcohol to act as a degreaser and wetting agent. By diluting the gum etch with water by an additional 5-10%, a still less viscous etch is produced for better buffing down. The resultant thin film will prevent any bridging of the very fine toner particles and allow for a better washout and proper application of a printing base.
The Wash Out and Printing Base
Wash out the image with a 1:1 mixture of lacquer thinner and acetone. As is the case with grease materials, a complete wash out is necessary for the vinyl lacquer base to hold. This seems necessary because the plastics in toners and commercial vinyl lacquer bases may not be compatible because toners are a styrene/acrylate polymer and acrylic resin mix. For a safer washout solution, try a 2:1 mixture of acetone and odorless paint thinner. Apply and buff the lacquer base to a thin film and coat with asphaltum as you would ordinarily.
It is also possible to remove the toner image without the use of strong solvent. After etching the plate, use the setting solution to wet the image. After a short time, check to see if the toner is soft and try to roll it off the plate with your fingers. I have found that the softened toner will lift off the surface of the plate in much the same way that rubber cement can be removed from paper. Use the ball of softened material as a pick-up eraser to go over the entire image and remove it. Sometimes I have added a small amount of acetone to the white gas mix just to make sure the toner is soft all the way through. While slow, this method produces less toxic fumes. Finally wash the plate with the 1:1 lacquer thinner/acetone solution to make sure all toner is gone from the surface.
Toner Images On Stone
Toner washes work just as well on stone as on metal plates. The only difference that I have found is that it is desirable to wash out the image well before using a commercial lacquer base. On stone the washout of the toner is never quite complete and must become a sealer so that the greasy asphaltum cannot react chemically with the stone. By applying a layer of vinyl lacquer on the surface, a proper printing base is put down which will producing large editions.
Use With Positive Photographic Plates
Because of the opaqueness of the individual toner particles, black toner washes on mylar produce exceptional images with positive plates. The reticulation on plastic is exciting and reproduces perfectly. The new positive plates and mylar drawings certainly make registration and printing less arduous. I have used both clear and frosted mylar but prefer the clear material because of the cleaner background produced on the plate. Black toner give excellent results.
The most interesting application is in the use of colored toners in combination with mylar film. Xerox and Cannon produce tri-color sets for their new full color machines and these open up a number of possibilities. I do my drawing on clear mylar using a punched registration system. Overlays for each color plate are produced with perfect registration and I have a better idea of the color relationships due to the color of the toners. The toners are mixed to get an approximation of the color of ink to be used and overlays are built up for the completed image. I have found that color toners can be class A or B, depending on their manufacturer and intermixing them on the same mylar may become a problem. Setting fluid either dissolves or does not set one of the toners when mixed together (depending on the setting fluid used). By mixing the color toners in a clear binder such as Future floor polish, brush textures rather than reticulation are possible; by greatly diluting the polish, it allows you to control the amount of reticulation. Various color felt markers are used for line work to keep the overlays in their respective colors. Some colored china markers closely duplicate the effect of grease crayon, especially if used on frosted material.
All colors except process blue and magenta produce a good image with the standard exposure for positive plates. Less exposure is needed for the blue and true magenta images as they allow more of the ultra-violet light through to the plate. By carefully controlling the exposure, all colors can produce accurate plates. I have successfully used the new UV blockers that are used to prevent sunburns by painting the gel over the problem areas on the other side of the mylar. This reduces the exposure in the selected areas. By producing the overlays in full color the artist can have a better idea of the effects of the colors as they will overprint and how they relate to one another. This cuts down on proofing which is an expensive and time consuming procedure for any edition.
It is possible to transfer toner images from a mylar sheet if the image has not been set. While it is feasible to do all your drawings first on the plastic and later transfer the image to plate, the greatest advantage of this technique in is printing multicolor editions. After the key plate has been printed with the registration system in place, it is easy to register a sheet of mylar to the print. The second color is applied to the mylar as a wash or with toner chalks on frosted material. After the toner is dry (in the case of toner washes), register the image unto a fresh plate without setting the toner. You must handle the sheet with care as the toner is unset and can be smudged. Assemble the tympan and run the plate through the press with considerable pressure. When lifting the mylar, you will notice that all the toner has been transferred to the grained plate, with only slight areas around heavy applications leaving a halo effect. Now set the toner with heat or solvent and proceed to process the plate. By working in this manner, multicolor editions are feasible with perfect registration.
Another interesting way of using toner transfers is to use two or more plates for the same image. Using registration pins, transfer only the thicker parts of the toner image under light pressure. If not enough has transferred on the first pass, try it again with more pressure. Keep the remaining toner in mind. On the second plate, transfer the remaining toner, using registration pins. One could even use a third plate if care is used in all transfers. By printing in different colors, some very interesting prints can be obtained.
While toner tusche has many advantages over traditional grease, some artist and printers might not find it to their liking. The wash does behave differently and does not exactly duplicate the grease wash. There is no ringing of the droplets and reticulation in toner is much more pronounced. I believe that many more possibilities exist with toners because of the brush textures available and the complete freedom this process gives for changing the drawing. Each artist will have to make-up their own mind and only time will tell if toners will give us the freedom they seem to promise.
Because of the superior desensitization of the plate, editioning is trouble free even in large editions. Air brushing and other effects are now no longer a problem. This technique, when used with my waterless lithographic process, will produce the simplest and cleanest running plate a printer will ever use.
For those artists who are interested in getting more information on the use of toner in lithography they may read my original article in LEONARDO. Although this paper contains all of the information necessary to make the process work, there are other facts in the LEONARDO article which may be of interest to some. For those interested in sharing information, they may contact me at the Department of Art and Art History, University of Saskatchewan.
USE OF TONER IN OTHER MEDIA
Because of the nature of toner, it can be used as an opaque material to produce positives that can be used in intaglio and screen printing. It can be bonded to mylar with white gas or by adding some sort of adhesive to the drawing mixture. Acrylic emulsion is a good bonding agent, but it should be diluted with enough water to allow the toner to reticulate, if that is what is wanted. Future acrylic floor polish is a good substitute for artist acrylic emulsion and is used by many. In intaglio, it can also be used directly by bonding it to a plate and using it as a resist, or for a positive image, a mask of specially made shellac can be flowed over the toner which is later removed to reveal the bare metal. Care must be taken as the fine toner particles can be quickly undercut by the acid and lost. Use heat to bond the toner as this gives better adhesion to the metal.
Toner is a very important part of my waterless litho process as it can be washed out after the silicone has cured. All of the toner techniques revealed here, can be used with my waterless lithography process.
Points to Remember
1/ Toners are being changed by the manufacturers and the same product number may react differently then your previous supply. If you have secured a fresh supply, make sure it produces the same image as the toner you are familiar with. This is really not too much of a problem but I have experienced subtle change in some products.
2/ When using type A toners and a solvent wash, the washes have little or no reticulation and can be quite smooth in transition. By selecting the proper setting method, class A toners give the artist much more flexibility than B type. I have found that a plain household paint stripping heat gun works very well setting the Type A toners I have tried. If a heat source is used, then class A toner could become your standard material and solvent washes an everyday occurrence. If my waterless lithographic technique is used, a heat gun would be an asset for quick processing. Remember, ordinary hydrocarbons will soften and set B type toners but have no effect on Class A material and can be used as a drawing fluid.
3/ Try a number of wetting agents to disperse the toner powder in water. Acrylic Flow Release is very effective as are some commercial liquid cleaners and household detergents. Those that produce suds leave an image as interesting as peau de crapeaud on zinc.
4/ Future Floor Polish as well as other emulsion polishes will mask the surface from the desensitizing etch. That is all that the toner particles are really doing until they are dissolved and replaced with a lacquer printing base. When mixed with black India ink, it makes a perfect drawing ink for pen work. It can be diluted with water to a proper consistency.
5/ Toner can be used as the imaging material with my waterless litho process that was developed in 1990
Materials Needed For This Technique
Toners: Toners can be obtained with no charge at copy centers and laser cartridge recharging facilities. You will have to test the characteristic of the material -- it could be A or B, or somewhere in between. If you get your toner from a cartridge recharging facility, make sure you mix your supply very well to intermix the toners which may come from every make of machine.
Toner washout solution: To reduce the amount of toxic vapors, make up a shop mix of acetone and lacquer thinner to washout the toner image. Because acetone is not as toxic as lacquer thinner, it is safer to use. Because it is more flammable, great care should be taken with it in that respect. Other solvents may be used such as turpentine and citrus thinner since both dissolve most toners I have come across. If you are going to use lacquer printing base, a bit of the shop mixture could be used for the final washout.
Wetting agents: There are a number of materials that can be used to disperse the toner particles. As long as there is no grease like in soap, they should work. Some produce a great amount of suds that can be used for interesting textures. The fluid used in the final dishwashing cycle is meant not to produce suds and you can take advantage of this characteristic.
Acrylic and vinyl floor polishes: While Future floor wax is mentioned in the text, there are any number of these plastic emulsions that should work. As long as the plate surface is protected from the gum etch, and can be removed with the washout solution, it should work. Spray lacquers and paints are another method of getting images.
Sumi ink: This inexpensive oriental black ink is very well pigmented and is perfect for adding color to the plastic emulsions used for drawing. It is available in some art stores and in most oriental stores. It is charcoal pigment ground is a simple glue solution.
White gas: A high grade naphtha used in camp stoves and lanterns. It has little or no waxes that can become a problem during etching. Known in the USA as Coleman Fuel.
Gum etch: While any good gum etch would work, I personally like the complete desensitization that the modified Singer etch gives. Because toner particles that are well bonded to the surface can take great abuse during processing, a better plate is produced.
A paper with the original information was received by LEONARDO December 19, 1985, then published in LEONARDO, Vol. 20, #1, pp 71-77, 1987
A MORE EFFECTIVE TYMPAN WAX AND AN INEXPENSIVE
REPLACEMENT FOR SCRAPER LEATHER
My earliest innovation was a replacement of tympan grease and scraper leather. In the North American market we have a wax ring that is used to make a water tight seal of our toilets to the sewer line. This wax is basically clear and very sticky, but has great lubrication quality on the tympan. It has only to be applied once to the surface and the excess then removed. There is no need to redistribute the wax at the end of each print pulled as the thin layer has more than enough lubrication. I have pulled over 150 prints on my own press at home with not ever replacing the wax. Only dust and dirt force the cleaning and replacement of the lubricant. You can check to see if the wax is sufficient by dragging a finger across the surface and observing the mark in reflected light. If a streak is seen, there is enough wax on the surface.
To replace the scraper leather, I have found that plastic underground sprinkler system pipe is perfect. It is black polyethylene/polyvinyl mix and has its own slight lubrication quality. It is split in half and stretched on the scraper bar, using pliers. While it has no stretch, the fact it is half round, lets it conform to the scraper bar. Since the price of the plastic pipe is only a few cents per foot, it cost pennies rather than dollars to change a scraper bar. They stand up to printing as well or better than leather, and slide easier over the tympan while under pressure. These materials have replaced grease and leather at this university since 1984 and are now used in New York and other places on this continent. This simple change has made printing cleaner and easier for our students.
Permission to photocopy this paper is given by the author. Publication without permission is prohibited. Send inquires and comments to: