The 20th century
Beginning with the invention of the offset technique, the 20th century saw the steady development of innovations in the direction of mass production, speed, and economy.
Discovery of offset (early 20th century)
At the same time, lithography was undergoing a new evolution. After the first mechanical presses had been perfected, this process had developed along two lines: (1) printing on thin sheets of metal (for example, tinplate for packaging canned foods) using a transfer process (1878) in which the impression cylinder carrying the metal sheet to be printed did not come in contact with the stone but did with an intermediary cylinder covered with rubber, the blanket, which transferred the image from the stone to the metal; and (2) printing on paper, which was done only comparatively infrequently in the last years of the 19th century, on cylinder or rotary presses.
In 1904 at Nutley, New Jersey, an American printer, Ira W. Rubel, discovered that an image accidentally transferred from the plate cylinder of his rotary to the rubber blanket of the impression cylinder during a paper-feed stoppage could itself be used for printing and in fact produced a superior impression. Rubel and an associate constructed a three-cylinder press, the first offset press, the term since used to describe this increasingly popular printing device.
Dry offset (1920)
A few years later a problem arose in connection with printing the background of checks with a water-soluble ink to prevent forgeries. It was proposed that the lithographic plate of the plate cylinder be replaced with a stereotype plate or with a letterpress wraparound plate. This process, which combines the relief of letterpress, which does not require wetting, with the transfer of offset, is known as dry offset, or letterset. Its area of application is not limited to check backgrounds but is used in all areas of conventional printing.
Since 1950 another process has been developed, particularly in the United States. It combines rotogravure with the transfer of offset for printing wallpapers, plastic floor coverings, paper plates, and other products.
color printing
As early as 1457 a psalter, which Peter Schöffer signed but which some researchers now attribute to Gutenberg, included, in imitation of the contemporary illuminated manuscripts, paragraphs beginning with ornamental capital letters printed in two colors. This was accomplished by the use of two wood blocks that fitted one inside the other and could be separately inked.
Experiments to reproduce pictures in several colors on wood blocks were made in Germany in the 16th century. In the 17th century, different inks were applied to the different parts of the same engraved metal plate in such a way that all the inks were transferred to the paper in a single pressing. In 1719 a painter, Jacques-Christophe Le Blond, took out a patent in England for a process that used the three primary colors, blue, yellow, and red, and black for outlining shapes. Using a dense grid, he engraved four metal plates, bringing out on each plate the relative importance of the color involved. The same sheet of paper then went through four successive impressions, each in a different color.
In the 19th century the scientific definition of the principles of trichromatism, the enunciation of the fundamental theories of three-color analysis and synthesis of colors by photography, the perfecting of coatings selectively sensitive to colors, and finally the use of the screen, instead of Le Blond’s hand-drawn grid, established the modern trichromatic technique (which becomes quadrichromatic when black is also used).
Automation of composition (after 1929)
The search for maximum efficiency had from the very beginning posed the problem of both the mechanization and the automation of composition. The Monotype system, with its separation of keyboard and caster, had constituted one approach to the solution, since the same caster could work at full speed when fed with perforated tapes produced on several keyboards.
The perfection of teletypesetter remote-control composing equipment in the United States by about 1929 permitted widespread application of the principle of separation of human function on the one hand and mechanized function on the other. The operator produces a tape on which each letter, symbol, and space is represented by a combination of perforations. A translator device reads the tape and, according to each combination of holes, orders the release of the necessary matrices for letters, signs, and justifying spaces. Machines casting one-piece fully spaced lines or slugs are able to produce more than 20,000 characters per hour.
Programmed composition (1950s)
The production of the perforated tape remained relatively slow, however, because of the time taken by the operator to decide where to make the division in a word at the end of a line. Eventually, in the second half of the 20th century, electronics provided the means of automatically making this decision.
In the 1950s the BBR system, named by the initials of three inventors in France, introduced programmed composition. Starting with a perforated tape continuously produced by the operator, a computer takes over the task of determining the length of lines, the places where words are to be divided according to grammatical rules and typographic usage, the integration of corrections, and even the presentation of the text according to the layout. The speed at which a final tape bearing this information can be produced is limited only by the performance of the perforator, which is the outlet device of the computer. Operating speeds have exceeded 300,000 characters per hour, or 10 times the capacity of the most modern slugcasting machines.
During the 1960s, perforated tape began to be replaced by magnetic tape, which is even more rapidly made, at a rate of about 1,000 characters per second, or 3,600,000 per hour. Although magnetic tape is useless for mechanical composers casting pieces of type or lines in lead, such speed is practical for other kinds of machines not burdened with the weight of lead and the inertia of their mechanical components.
Photocomposition
In preparing cylinders for rotogravure, offset plates, or letterpress wraparound plates, it is illogical to use the vast weight of lead in letterpress composition to produce a reproduction proof that will then be photographed. Before the end of the 19th century this circumstance led to consideration of machines for composing headings by photographing the images of the letters in succession. In 1915 the Photoline, a photographic equivalent of the Ludlow, assembled matrices of transparent letters in a composing stick in order to film each line of the heading.
First generation of phototypesetters: mechanical
The next idea to be tried involved the adaptation of existing typesetters by replacing the metal matrices with matrices carrying the image of the letters and replacing the caster with a photographic unit. The industrial application of this idea resulted in the Fotosetter (1947), a phototypesetter, and its variant the Fotomatic (1963), controlled by a perforated tape, both derived from the Intertype slugcasting machine; the Linofilm (1950), derived from the Linotype; and the Monophoto (1957), derived from the Monotype. Retaining the mechanical limitations of machines intended to shape lead, they could not achieve appreciably higher rates of performance. Photocomposition had to be rethought in functional terms. This approach was explored in Germany as early as the 1920s with the Uher typesetter, which had photographic matrices attached to a rotating disk.
Second generation of phototypesetters: functional
The second generation of phototypesetters is characterized by the maximum elimination of factors of inertia, the number of moving parts having generally been reduced to only two: a steadily revolving disk or drum carrying the photographic matrices and an optical device of prisms or mirrors allowing directional action on the beam of light provided by an electronic flashtube.
The first revolutionary application of this notion was the Lumitype, invented as the Lithomat in 1949 by two Frenchmen, René Higonnet and Louis Moyroud. Executed by phototypesetting, The Marvelous World of Insects was done on their machine in 1953. The first model had an attached keyboard. Later models with a separate keyboard printed more than 28,000 characters per hour.
A new Linofilm (1954), functional and electronic, was fitted with a device for selecting matrices by the action of the blades on the photographic shutter, producing 12 characters per second, or 43,200 per hour. The model that succeeded it (1965) is equipped with a drum and is capable of double the output. The Photon-Lumitype 713 (1957) also performs at the rate of 70,000 to 80,000 characters per hour. But at this speed the technique of using a rotary matrix case reaches its limit because of the problems posed by centrifugal force. The Lumizip 900 (1959) introduced a further revolutionary change by retaining as moving parts only the lens, which scans in a single movement the fixed series of light matrices so as to photograph at one time the whole line of 20 to 60 letters. Output reaches 200 to 600 characters per second, or more than 2,000,000 per hour; this machine required magnetic tape.
The first book composed with a Lumizip, the Index Medicus (1964), was as much of a landmark in the history of phototypesetting as the Forty-two-Line Bible had been in printing. Its more than 600 pages were completed in 12 hours. To produce the same work on a typecasting machine would have taken almost a year.
Third generation of phototypesetters: electronic
Magnetic tape was still faster than the fastest phototypesetters. To narrow this gap, a third generation of phototypesetters appeared in the 1960s, in which all mechanical moving parts were eliminated by omitting the use of light and therefore omitting the moving optical device responsible for operating in its field.
Cathode-ray-tube phototypesetters (RCA, Linotron, etc.) operate on a principle analogous to that of television: a narrow pencil of electrons analyzes an image matrix of each letter and commands the modulation of another pencil of electrons on a luminescent screen, which leaves an impression on photographic film. Performance exceeds 500 characters per second and even approaches 1,000, or more than 3,000,000 per hour.
Digiset, a German development that appeared in 1965, pushed the use of the electron to its logical conclusion by suppressing even the image matrix of the character, simply keeping the binary analysis of its design available in its magnetic memory; this is, in fact, all that is needed to modulate the pencil of electrons on the final screen. Phototypesetters of this kind (called alphanumerical) have theoretical performance rates exceeding 3,000 characters per second, or more than 10,000,000 per hour, and should be able to approach 30,000,000. Speeds such as these exceed the production rate even of magnetic tape. Consequently, to work at its most efficient output, such a typesetter must be directly connected to a computer with a similarly high rate of output.
Toward direct impression
The number of characters thus composed now approaches the number of characters printed on a press in the same time. The narrower this gap becomes, the more a still further revolutionary possibility looms—that of eliminating the press itself, since the typesetter can be made to deliver each page as quickly as the press would have. To accomplish this it would be necessary only to replace the photographic film that the photographer imprints when it is conventionally used with an inexpensive carrier capable of receiving an image in the same way without pressure.
Several pressureless printing processes have already been perfected. In 1923 an electrostatic onset system drew the ink of a cylindrical typeform to the paper by means of an electrical charge. In 1948 two Americans conceived another type of electrostatic printing in which the coloring agent is not ink carried on a typeform but a powder or a solution sensitive to the pull of an electric charge inscribed in a plate. This technique gave birth to xerocopy in office duplicating (see below Office printing) and, at the industrial level, to xerography for producing posters and maps.
Printing without pressure can also be accomplished on papers impregnated with photosensitive preparations and passed in front of a cathode-ray screen of a phototypesetter. The first experiment using this facsimile printing process was carried out in Japan in 1964 by the Mainichi shimbun, a Tokyo daily newspaper. The image of the newspaper page formed on the cathode-ray screen was transmitted by radio waves, as in television. It was reproduced using the electrostatic system, which does not require chemical treatment of the paper after its exposure.
