Polymetaal

A technical dictionary of printmaking, André Béguin. EN

Lithography is a printing technique that gives multiple reproductions of an image drawn with ink or crayon on a certain type of limestone. The image must be prepared with a chemical process so that the grease contained in the ink or crayon (both being specially made for lithographic work) becomes permanently fixed to the stone. When the naturally absorbant stone is wetted before printing the lithographic ink will be retained in all areas containing grease and repelled in all other areas. The characteristic of this printing technique lies in the fact that the image area and the non-image area react differently to the presence of ink.
Lithography became, as of the beginning of the 19th century, the third printing technique coming after the more ancient relief* plate printing and intaglio* printing. lt will be remembered that relief printing is the method in which only the raised surface of the plate (the image) is printed whereas intaglio printing is just the opposite since ink is stuffed into lines cut into the plate and thus the image lies below its surface. ln order to differentiate lithographic printing from intaglio and relief printing it has also been termed planographic printing. Lithography has sometimes been considered as a type of engraving* technique but this is hardly justified since the etching that the stone undergoes, when being prepared, produces only a microscopic relief.
Relief printing can be said to have produced the invention and development of typography on an industrial level. lntaglio printing can be said to have produced photogravure. Lithoqraphy, on the other hand, can be said to have been at the root of offset which is one of three most important printing techniques used today.
Contrary to intaglio and relief printing, the origins of lithography are very well known. In fact, the inventor of lithography, Aloys Senefelder (1771-1834), left a detailed description of the birth of this technique. His discovery originated in his need to find a cheap way of printing his own literary work (plays). At first Senefelder tried to cut relief letters into copper plates (in reverse, so that when printed they would be right side up) but the difficulties encountered were such that he soon turned to a kind of stone easily found where he lived. This stone, called Solenhofen stone after a town near Munich, was a very dense limestone. This stone took very well to being polished, being etched in order to bear letters, and even to being used to print with. lt was pure chance that caused Senefelder to discover that this stone could also be used for relief work, a method which turned out to be much better for inking and printing. ln order to work in relief he used an ink that he had invented to make corrections and which contained wax, soap, and lamp black. The printing press he used was what he called a "stangen oder Galgen-presse". These discoveries were all made in 1796 but lor the time being his technique was hardly more than an adaptation or variant of the traditional relief techniques. Senefelder proceded to use this method to print "with uneven results", some adresses and visiting cards. By experimenling he managed to improve his invention and by 1799 he had perfected his "chemical" method. This chemical

The role of the lithographic printer was -and still is - of great importance. Moreover, the work done by these printers has been of capital importance in the history of print making. Not only must the printer guide the artist but he must also complete the artist's work in this branch of the graphic arts. This task is harder than it may seem. For example, the stones used in lithography are not neutral supports (as paper is) since they must be penetrated or scraped to a very precise degree for proper use.
lt is true that photomechanical processes meant the death of industrial lithography as of the end of the 19th century but, on the other hand, it is also true that photomechanidal processes forced lithography to develop yet further. In 1855 L.A.Poitevin had invented photolithography or a photographic reproduction technique on stone using bichromated gelatin and a chemical printing method. However, photolithography had less success than photometallography which worked on the same principle but used the more manageable and lighter zinc plates. The photographer Niepce knew lithography quite well and had tried to make photographs using stone and zinc as early as 1815. His process came to be known as heliographie (not to be mistaken with the English term heliography) a term which (as far as Niepce was concerned) included the reproductlon of an image by photographic means whether the printing was intaglio or planographic [* heliography, photo-engraving, photography).
Senefelder soon realized the advantages of using zinc plates and proceeded to prepare such plates chemically. Thus it was not a big step when photography came along and added its precision to the zinc lithography process. Above and beyond the advantage of its light weight zinc could be curved without any problems and could therefore be used on the rotary presses that became ubíquitous as of the 1880's.
(the first stone printing machine was built in 1863 by H.Voirin. Others were later built by Brisset and Marioni. See printing presses ).
ln 1904 Rubel, an American, perfected this type of zinc plate printing by interposing, between the chemically prepared plates and the paper, a roller covered with rubber. This roller, called a blancket* roller, carried the image to be printed from the plate to the paper with greater fidelity. A further advantage was that the plate did not need to carry an inverted image since the two-fold transposition (first onto the blancket, then onto the paper) made the image come out in the right direction. This new printing system was called offset in most countries but, curiously enough, in North America it was still called "lithography".
Another process derived from lithography is phototype*. This technique uses the properties of bichromated gelatine which is applied to a sheet of glass. The next step is to/ expose this glass to light shining through a reversed negative. The glass is then wetted and the areas that were not exposed or only very little exposed will swell up. The damp swollen areas will refuse the oily ink used in this process whereas the hollows will retain the ink [* phototype].

 II. THE MATERIALS

1. SUPPORTS.

lt has become a wide spread habit to use the word lithography lor the technique on stone first perfected by Senefelder as well as for a similar technique using metal plates. For reasons of clarity "lithography on metal", which used to be called metallography, will be treated separately further on. However, insofar as supports are to be discussed here, it should be mentioned that lithography can be subdivided into two basic categories, the first being lithography done on stone and the second being lithography done on metal (zinc or aluminium). The category of lithography on stone also includes the work done on imitation stones, a technique described further on even though imitation stones have now become rnore of an historical curiosity than anything else.
During a trip to France Senefelder, who was still trying to work with copper, discovered the existance of a finely grained stone in the Dauphiné. Shortly thereafter he found a much more appropriate stone in Solenhofen, a town on the Altmühl river in Bavaria. The stone in question was, and still is, a very homogenous and hard stone which is closely related to jurassic formations. The chemical analysis of this stone gave the following proportions of the components:

calcium carbonate .. .. 97,22
silex...... . . . . . .. 1,90
alumine....... . . . . . . . 0,28
iron oxide......... .. 0,46
others............... . . . . . . . . . ... 0,16

Towards 1920 the Solenhofen quarry began to show signs of depletíon but the crisis of lithography saved it from being exhausted. Other quarries in the same neighborhood also provided good quality stories that were appreciated for their ability to soak up water or fatty substances. The French stones came from Chateauroux, Le Vigan, and Perigueux but the grain of these stones was coarser and the colour darker.
The Bavarian stones have two different basic colours: gray and yellow. There are, however, stones which come in closely related colours such as charcoal gray, white, and reddísh gray. Below l will discuss how to choose stones in function of their colour.
ln recent years an enormous amount of lithographic stones have been thrown away because many lithographic workshops have closed for good. l have even seen little walls built with such stones in the South of France. At present the trend seems to be reversing and as a consequente new workshops are opening and the stones are again being sought after. The stones that can be had often come from old workshops and still bear the traces of previous work; at times this work obviously dates from the last century. In fact, 19th century lithographers often kept their stones for further runs. A well protected stone can be kept for an indefinite amount of time and can periodically print a large amount of irnpressions if the image is properly protected.
Lithographic printers have a large choice of stone qualities and sizes to chose from. The dimensions may be close to the paper sizes [* paper sizes ] being just a little bigger than the paper to be printed on. In some old workshops one can still find the very large stones that were used to print posters and billboards. The Bavarian stones could be as large as 120 x 76 cm (47 x 30 in) The largest lithographic stone was exhibited in Paris in 1889 and measured 230 x 150 cm (90 x 59 in) lt was a stone that had been quarried at Le Vigan. The prices for the stones sold by the quarries included the planing and polishing of the stone on one side only.
If an artist wishes to work at home (i.e. if he doesn't have his own workshop) he should transport only small or medium sized stones. On the other hand, it is usually better to leave the stones in the printing shop where they will be kept at a constant temperature. lf large format work has to be done it should be carried out in the printing workshop itself. Usually the printing workshops are set up so that there is enough space for several artists to work there simultaneously. lnsofar as the corrections and final touches are concerned it is usually easier to work in one of these workshops.
Senefelder was the first to try and make imitation stones as early as 1814. He tried to make such stones for two reasons in particular: in order to reduce costs and to solve the weight problem. ln fact, for large format stones several men had to help to lift them about. Senefelder tried to copy the composition of the stones found in the Solenhofen quarry and thus prepared a mixture of calcium and linseed oil to which he added clay and some iron oxyde. Since this mixture did not give satisfactory results he tried another set of ingredients: white lead, lime, and caseine. The mixture was then spread on a heavily varnished sheet of paper. His invention came to be known as paper stone but unfortunately this support did not last for more than a few hundred impressions which, in those days, was insufficient for the commercial uses it aspired to fulfill.
Knecht, Senefelder's nephew, made a more resistant imitation stone using the following ingredients

 

 and proportions:

lt was said that this "stone" could handle some six hundred impressions.
ln 1841 Kuhlmann made an artificial stone by boiling chalk tablets in a dissolution of potasium silicate.
ln later years experiments were carried out by Von Hertling and Capitaine who mixed dust from old llthographic stones with a solution of coton powder, all of which was added to a mixture of alcohol and ether. The paste obtained by this mixture was then moulded. The next step in the search for imitation stones was to abandon the idea of stone and turn to other substances. Experiments were made with celluloid poured on zinc plates but this and other experiments failed while the use of stones continued.
On the other hand, metal plates, which were also a substitute, began to be used as of 1822 but, as was mentioned earlier, this process will be dealt with separately (see point IV).

2. MATERIALS USED IN READYING THE STONE .

The stones used for lithographic work are quarried at a certain depth. The upper layers, which are two meters deep (six feet) are not suitable for lithographic use because the stone is too soft and absorbant and therefore it is usually used for paving. Below this first layer the stone is cut into blocks, each block being made up of several layers that can be anywhere from three to twelve centimeters thick (1.2 to 4.8 in). The layers must then be separated from each other but the iob must be done very carefully as it is a delicate task. The next step, which is carried out in the quarry, is a first shaping of the stone which is chiseled into approximate sizes and cut into the proper shape. Usually the quarries also carry out the next step which is to clean the two surfaces of the stone and make them parallel to each other. This step can be done manually, stone against stone, much in the same way as the pumicing described below is done. At this stage, however, the work is generally done with machines in which case the stone is fixed onto a cart. The stone is then rubbed with two plates set in with metal blades.
The blades turn on their own axis while the plate girates thus achieving two separate movements. The stones are delivered with only one side polished unless special ,conditions are requested. This procedure, described above, is currently followed by the few German quarries that have opened again.
Although the printer receives his stones ready for use he still has to carry out further preparations according to the use he intends to make of the stone. ln fact, he may have to grain it or polish it further. Another job done by printers is the recycling of used stones. Stones that have already been used must be cleaned so that none of the previous image remains. Only then may a new image be drawn.
This cleaning is done on a special table which must be very large and solidly built so that it can carry even the heaviest stones. The stones worked on this table must be no bigger than the table top. The table is built with an opening in its surface below which there is a kind of cone lined with zinc or lead.
This cone collects the water and mud that run off the stone while it is being pumiced and draíns them through a little hole in the bottom. The sizes of these tables are usually 135 x 100 cm (52 x 39 in), 100 x 85 cm (39 x 33 in), and 100 x 75 cm (39 x 29 in).
The pumicing, graining, and polishing of stones is done with various abrasives* including sand from river beds, sandstpne, or powdered carborundum. A sieve is needed to sift the abrasive to the same size. lf the abrasive must be crushed a graining disk wlll be used on the stone surface. A gralnlng disk is a rounded block of cast iron whose surface (the one in contact with the stone) is either smooth or full of little holes These holes prevent the disk from sticking to the stone surface. There is an off-center handle on the disk which turns on its own axis and causes the disk to rotate. The handle is meant to be held with the right hand while an increaslngly fine abrasive is powdered onto the stone with the left hand. The work is then finished off with a sandstone brick with holes in it (the holes facilitate the evacuation of sludge and air, both of which can cause the brick to stick to the stone). Other types of bricks are also used, such. as those made with pumíce stone dust. Sealing-wax bricks are made with pumíce stone dust of varyirig degrees of fineness mixed with alum and wax. They are used for polishing and finishing stones (see below and under grainíng and polishing).
When industrial lithography was still practiced a variety of machines were sold that carried out the various steps described above: there were machines for levelling the stones, for pumicing, for graining, and for removing previous images. A more detailed description of these machines will be found in the article devoted to machines in general [* machine].
The big workshops of the past also had two-wheeled wagons with which the large stones were moved around. These wagons were needed because the stones could weigh as much as one thousand kilos (2,200 pounds) and because they had to be moved about from the pumicing area to the drawing area, from the transfer area to the printing area, etc. Although these different areas were all at the same level (on the same floor) they were distinct and separate working areas.
Another accessory in lithography is the metal ruler with which the levelness of the stone is checked during the pumicing procedure.
The reason all of these procedures have been classified as belonging to the readying of the stone rather than the process of preparing in that a certain confusion could arise when using the latter term. ln fact, the term preparing the stone is traditionally used for the rather particular operation that follows drawing on the stone and precedes the actual printing.

3. MATERIALS FOR DRAWING.

A. INKS AND CRAYONS.

1.- INKS. In his book "Art de la lithographie" Senefelder mentioned how he discovered lithographic ink. At the time he was busy experimenting with the engraving of letters (íntaglio work) and practicing backward writing on stone (which he had chosen as a fairly cheap support). One day he recounts, "I had just finished shaping the stone and was about to apply some mastic in order to continue practicing backward writing when my mother came in and asked me to write down the list of the laundry she was sending out to wash. The washerwornan was waiting impatiently while we were looking for a sheet of paper. Chance had it that all the paper had been used up by my experiments and that my usual ink had dried up. Since there was nobody in the house at the time who could go and buy the necessary supplies I decided, on the spot, to write the list down on the stone using my ink which was made of wax, soap, and lamp black. Later on, when l wanted to erase the list l suddenly wondered what might happen to the words I had written with my waxy ink if l applied some mordant to the stone. l also decided to try to blacken the letters, much in the same way as letters are blackened in printing or woodcuts, and then try to print them." Senefelder thus discovered his first lithographic technique using an acid resistant ink. This first technique was a kind of variant of traditional relief* engravings. Senefelder subsequently carried out "thousands of trials" since he was annoyed by the difficulty of writing backwards on stones so that the impression itself would be right side up again. During these experiments he began to develop the first transfer” methods that allowed him to draw normally and print right side up, thus avoiding the problem caused by writing backwards. The transfers he experimented with were done on paper using a special ink transfer ink, which could be transfered onto stones by mere pressure. During this phase of experimentation Senefelder also perfected anastatic* printing, a technique that was used to reprint texts using an oily ink. Anastatic printing used a transfer ink made of colophony, powdered litharge (lead monoxide), lamp black, potassium, and an oily varnish all of which were mixed and diluted with water. The transfer was then made onto paper (rather than onto stone) so that the writing was backwards. This transfer was then used for printing so that the writing was finally right side up. This rather curious transfer system led Senefelder onto what was to be chemical lithography .
ln his own words: "l noticed that a sheet of paper which had been written on with lithographic ink and had been properly dried could be soaked in water that had a few drops of any oily substance in it and that this oily substance would be caught on the written parts. The rest of the paper, especially if soaked in water containing gum arabic or in a very deluted starch solution did not catch any of the oil." This observation "of the greater or lesser attraction of one substance for another " led Senefelder to yet another consideration. "Couldn't one prepare a more solid substance and even stone slabs so that they would catch colour in those places where oily ink had been applied and refuse colour where they had only been darnpened?" From this point on it was a matter of course, if one may say so, that he proceeded to take a "well finished stone on which I drew with a little piece of soap. I then put a weak solution of gum arabic and water onto the stone. After that I rubbed the stone with a sponge impregnated with an oily colour. The result was that the areas of the stone which had been touched by the fatty soap picked up the colour and became black whereas the other areas stayed white. The stone could then be used to print as many impressions as l could possibly desire for all l needed to do was to wet the stone after each irnpression and rub it down with the sponge."
The purpose of the soap used by Senefelder was to make the stone retain the ink much in the same way as serigraphers use it today in order to make their rubber base ink easier to work with. Soap therefore acted as the essential fatty agent in his discovery. Lorilleux gave a good explanation of the use of soap in lithography in his "Traité de Lithographie" published in Paris in 1889: " In order to use a brush or a pen it is absolutely essential that a fatty agent be combined with another substance having analogous properties so as to obtain a sufíiciently fluid liquid that would penetrate into the pores of the stone but would not spread beyond the margins of the lines that were drawn. This essential condition excludes the use of oils, essences,and alcohols. Nothing is left to use but water. However, fatty agents, resinous or bituminous, are insoluble in water and in order for thern to become soluble they must be saponified i.e. they must be decomposed with alkali. This necessity explains the presence of soap in all lithographic ink recipes. Thanks to soap the oily ink can be used as a watery solution. On the other hand its role as a solvant will cease as soon as the acidulous solution is applied. lf one pours a few drops of an acid liquid into water containing dissolved soap the alkali combined with the fatty agents are neutralized and, as a consequence, the fatty agents become insoluble once again. The fatty agents precipitate forming flakes which float to the surface where they can be removed. This is what happens when acid is added to ink."

The other main ingredients used in lithographc ink are wax, tallow, and resin.
As l have already mentioned wax was used by Senefelder mixed with equal proportions of soap in the acid resistant ground he used for his first lithographic experiments. Wax gives consistancy to the ink and " limits the tendency of the fatty bodies to spread beyond the lines drawn on the stone. Furthermore, it limits the effect of the acid preparation by retaining the molecules of the fatty agents reconstituted by the acid when it neutralizes the soap. lf there is too much wax the solid ink becomes hard and breakable. When the ink is dissolved it only stays clear for a very short span on time and it is often necessary to add some drops of distilled water or rain water to it before use." (Lorilleux).
Senefelder, on the other hand, pointed out that in order to thicken the ink "one can use wax which is heated in an iron pot until it catches fire. The heat must be maintained until half of the wax has burned away. The longer the wax burns the more it will thicken."
Tallow is used to increase the fatty content of soap. Sheep tallow is usually chosen because it contains less oleine and less oil but still has enough of the free fatty acid necessary to fix the image to the stone. A neutral fatty acid that does not contain any free fatty acid, such as vaseline, would not do the iob correctly. The fatty acid content must be at least 10% in order to ensure a chemical reaction with the stone. In the case of the aluminium plates used in lithography there is no chemical reaction but rather a phenomenon of adsorption* (for further details on aluminium plates see below under metallography).
Resin, once it is dissolved and saponified, lends fluidity to ink. "Too much resin makes the ink dry, breakable, and hard to dissolve when cold. lt also makes it spread on the stone to such a point that only medium sized lines can be drawn."
An excess of soap or tallow in the ink makes the ink soft, sticky and easy to dilute in water.
There are many recipes for making lithographic ink all of which use soap, wax, tallow, resin, and various other ingredients in order to make the ink easier to use for different kinds of drawing. Senefelder came up with various recipes most of which included a high proportion of wax. However, according to him "there is little difference in the quality" of the different inks except when lac is added as this keeps the ink fluid for a long time but is hard to use. The following table contains Senefelder's recipes. The amounts that are indicated are all in proportion to each other.

Senefelder also mentioned a recipe developed hy André d'Offenbach who was his first associate as well as the financer of his lithographic printing works. This ink "has the advantage of staying liquid for years on end". According to Senefelder this ink is particularly suited for writing texts and music on stone.

In the article on ink* the reader will find thirteen recipes for lithographic ink (taken from Lorilleux). Alfred Lemercier, in his treatise "La lithographie française ...", speaks of five essential recipes for lithographic inks. The ingredients of these inks are the following, all measures being in grams (0,035 ounces):

The recipe in the fourth column was developed by Lemercier and was much used in the 19th century. lt was used above all for large splotches of solid colour and for writing with a brush. lts drawback is that it thickens too fast.
ln his treatise on lithography Engelmann speaks of some interesting recipes which he gathered from several sources and which are described below:
The first recipe comes from Desmadryll senior and is an ink for pen work. Engelmann spoke of this ink as being the one with which he had "constantly the best results".

Another recipe for pen work, also invented by Desmadryll, is a soft ink which does not harden much and therefore is dangerous to use because it can be accidentally rubbed away. According to Engelmann it does, however, "flow well and permits the drawing of free flowing lines".

In opposition to this soft ink there is a hard ink made with borax that was mentioned by Senefelder.
Its ingredients are:

The borax and lac are put in a container filled two thirds with water. The mixture is boiled for one hour and the evaporated water is replaced. After the mixture is cooled it must be filtered. The result, which can be kept for years, is mixed while hot with very fine lamp black or with finely ground cinnabar so as to obtain a thick ink whose consistancy is that of honey. lf necessary add some water while the mixture is still hot.
Engelmann also mentions another ink which he invented himself. This ink which is more viscous than the preceedlng one is meant to be used with a brush. The ingredients are:

Several other recipes are available for pen work. Amount these may be mentioned the ink used by Granville and Henri Monnier in making their drawing fnr "La Caricature" and "Le Charivari" (famous 19th century newspapers.) The ink they used had the following ingredients:

 to be continued 21-10-2023