The printing works is a whole of Technologie S making it possible to reproduce writings and illustrations in great quantity on plane supports, generally of the Papier, and to thus be able to distribute them to large scales. The Technique S go from the composition of the texts to the shaping (Reliure, Pliure…) while passing by the impression and the second reading.
The history of the printing works is closely related to that of humanity. Since the man developed means of communicating (cave paintings, writing…), he sought to perennialize his works and to diffuse them.
Egyptian scribes, which engraved the stone, with the monks medieval copyists, who spent their days to reproduce works - nuns for the plupart - by recopying them with the hand, the man very quickly sought to automate these means of copy.
See Chronology of the history of the press
Thus appeared the first wood engraved allowing the reproduction of many writings, of engravings: the Xylography. Then one used the stone engraved with the back to which one applied the ink which went in its turn being posed on paper: the Lithography. The stammerings of the typography encountered a problem of size: in the event of error, it was necessary all to remake.
Johannes Gensfleisch, more known under the name of Gutenberg, had the idea, about 1440, to use a similar process: the use of the mobile characters in Lead. One allots to Gutenberg the birth modern Typographie, but the latter existed already in Korea. Of this evolution, one will thus retain two types of books. Incunable S, books of the era pre gutenberg published between 1450 and 1500, and books known as modern, resulting from the typography and the more modern techniques such as the offset printing or the photogravure.
The innovation which Gutenberg in Europe will have initiated will play a considerable part in the reduction of the production costs of the book in Europe, and will thus make it possible to widen very significantly the diffusion of it.
The owner of the printers is Saint Jean Porte Latin. Printing works is a long time enorgueillie certain traditions very coloured such as Article IV and one song (D) astonishing accompanying it, With….
The activity of printer remains a long time at the stage of the small craft industry: the wages are weak but work is prestigious. The book is still a rare object and the typographer lives permanently in contact with the well-read men, which distinguishes it. Important privilege: it is entitled to the port of the sword.
A workshop employs on average, in addition to the Master who deals with the corrections, some type-setters who assemble the types and some pressiers. The apprentice is the odd-job man: he must know to read and write Latin and the Greek, and will make his training during two to five years with the service of the Master. After its training, become companion, it will make his “turn of France”, to perfect its trade before being established, as it is the case in all the trade-guilds since the Moyen-âge.
The printers sign their works and one finds their name on the books which they printed. The mark of a Master can be “Blason born” and thus constitute a kind of Héraldique of trade, as it was the case for the companions busy stone masons. The marks of printer comprise letters: the letter X (which evoke the Chrisme), V, S, as well as the Alpha and the Omega. It can make appear symbols like the sphere and the cross. It also massively uses famous “the Four of Figure”, marks mysterious and deeply christic, which did not deliver all its secrecies yet.
The typography occupied the scene of the communication of the 16th century until the third quarter of the 20th century. Modern times saw appearing novel methods of reproduction both for printing works itself office automation. Xerography, process of photocopy, the mimeograph, the facsimile (telefax). Graphic industry was seen equipping with new tools with the advent of the offset printing where one replaced the characters in relief by a process of carryforward of ink and water on a plate offset. The parts not to be printed receive water and the parts to be reproduced, the ink, which is hydrophobic. The plate is then in a hurry against a strainer and the strainer prints by carryforward the sheet. This process made it possible to introduce the impression in Quadrichromie, i.e. in colors, the spectrum being reproduced starting from three primary colors (cyan, magenta and yellow) to which one added the black in order to save on the colors and to give more contrast to pullings colors.
The Xylographie was practiced as of the 9th century in China, Korea and with the Japan. A million Buddhist texts Chinese were printed on the order of the empress Koken between 764 and 770, and were locked up in as many Stûpa. Several hundreds of these small documents arrived to us.
The oldest dated xylographes were discovered:
The Chinese were the first to use the mobile characters, at the 12th century. This technique their made it possible to preserve the cultural traditions accurately. The Chinese inventor pi Ching would have employed as of 1041 of the mobile terra cotta characters.
The metal characters would have been born in Korea about 1234. The oldest book printed starting from mobile metal characters goes back to 1377. It is about the Jik ji sim kyong.
In the years 1940, one imagined to substitute for the type-bars a plate which could indifferently comprise text or an image. This printing plate fixed ink at the places wanted by electrostatic load (plate known as “electrographic”) or by insolation (“stereotyped”). This technique gave rise to the first photocopiers and opened the way with the design of the plates offset.
In parallel, the composition was computerized. One saw appearing, at the end of the Années 1960, beginning of the Années 1970, the first processes of Photocomposition. A system of mirrors, in which the character S were openwork, served as “stencil key set” with the light which was going to impress a significant surface, the “bromide”, which was then revealed and fixed like an ordinary photographic paper. Texts thus composed - with the kilomètre - were going then to be gone up on the supports and the page layout was done manually. The completed assembly, one carried out a stereotype of the whole then one insolated the plate which was going to be used for the impression. Photocomposition and the pulling offset went perdurer almost twenty years, the processes evolving/moving with the appearance of the Laser which was going to insolate films directly, making disappear the systems with mirrors. As of this time, the books “were not printed more” as it was still the case with the Linotype machine: one does not see any more the pressure of the characters on paper, ink is simply absorbed on paper at the place where it is fixed by the plate offset.
The great turning of this end of century was the appearance of the first personal computers and especially of the Macintosh, at the beginning of the Années 1980, which saw the birth of the Desktop publishing (CAM). This microcomputer allowed for the first time to do everything on the same station: acquisition of digitized images, Final improvement of image S, creation of vectorial drawings, page layout with dedicated software, allowing to amalgamate texts and images. These operations were already possible on dedicated systems but at the prohibitory cost. Macintosh, in particular, made it possible to make this trade accessible while causing certain skids.
Parallel to the evolution of the composition, it is all the graphic Chaîne which knew, these last years, of deep upheavals. Thus, starting from the station of composition, photoengraving and page layout came to associate various peripherals of writing such as the CtF (Computer to Film) , called so flasheuses, which make it possible to insolate films of each color of impression (four in the case of the quadrichromy) in order to produce the plates by optical transfer. Large progress which makes it possible to do without the manual assembly of the page layouts. However, the optical transfer has this disadvantage which it makes lose of the definition in the points of screen and does not exempt final improvements on plates, because there can be “pétouilles”, parasitic deposits due to dust.
The following evolution was the CtP (Computer to Plate) - engraver of plaques - where the film was replaced by the plate (aluminum bases in general, sometimes out of polyester) which will then be insolated or “engraved” directly starting from the electronic file. Then, the operator does not have any more but to fix his plates directly on the press.
Last evolution in date, concerning the traditional press offset, it is the loading of the CtP system on the press. It is what one calls DI (Direct imaging). There is not then more intermediate operation between the station of page layout and the press, engraving being done directly on the cylinder plate carrier of the press offset. Favors: exceptional location of the various groups and time-savings of chock.
Another crenel was born from the last evolutions of the photocopiers, they are the presses known as numerical where all the traditional system was replaced by systems of transfer of image of the photocopiers type, allowing instantaneous and faithful pullings then document of entry (file, test…), but with a largely higher cost, which holds it, for the moment, with a short pulling.
Connected to Databases, these processes of numerical impression also make it possible to produce documents containing of the texts and the variable images.
In this process, the image “copied” from the printing form (metal plate) after treatment will be represented by the “sensitive layer” fatty by nature, while the part without image will be represented by stripped naked metal of its layer (treated aluminum) which is absorbent for him.
The plate will be then humidified, the “white” parts will fix water, while the “fatty” image will push back water and will be able to accept ink (fatty).
The process off holds its name of English “set” because the image is deferred plate printing to a “rubber strainer”, then strainer with paper.
It is the size and the depth of the “cells” which determine the tonality of the color and reproduce the gradation of the image.
The Encre used must be very liquid to make it possible to fill the cells well.
The flexography allows the impression on very varied supports. One prints primarily food packing. The flexography makes it possible to use inks with fast ultra drying or by ultra-violets.
Part of this screen is masked (by use of a photographic process) and ink crosses only the naked parts of the silk screen which interposes between the support and ink.
This technique has the advantage of being able to apply to supports varied and not necessarily flat (bottles, boxes, textiles, machines, wood, etc…) and on large surfaces.
It is about a process employing a stereotype on made up celluloid with the typewriter, which is reproduced using a solution containing alcohol on a rotary press (the Cyclostyle) also called “machine with alcohol”.
Thereafter the Photocomposition appeared which generated the text by projection of a beam of light through a matrix (kind of negative screen) producing the result by insolation uninterrupted on film in roller. These machines were often connected directly to a developer for an automatic treatment uninterrupted.
Later the advent of data processing allowed the input of the text (composition) directly on computer with the assistance of a data-processing software. The result being obtained on easily exportable electronic file. Thus often the text directly will be seized and provided by the customer.
In certain cases one uses a technique allows to recover already printed text using a scanner and of a software of Optical character recognition (OCR).
It is the work of the Desktop publishing (CAM). It takes as a starting point the model provided to make the page layout and follows on its screen of computer the railroad which define the pages and the sites of the headings, publicities, Hors-texte, etc --
In the past the tests were carried out in photoengraving on presses with counter-proofs giving to a result enough flator but difficult to reproduce by the printer. However much of printing works being equipped with presses printing two colors at the same time, they asked to the photoengraver tests accompanied by “progressive ranges” variation of the assemblies of colors used by the machine of the printer (green range for some, violet for others). The evolution of the number of presses 4-colors is such as well as the disproportionate cost of the investment and complexity for the photoengraver that this kind of tests was completely abandoned.
In a traditional way starting from films provided or obtained by the technique of the flashage CtF.
Or directly according to the numerical file finalized by the technique CtP
In the traditional method, the films “are copied” by “insolation” from the metal plate which is then developed by a chemical process.
When the customer is satisfied and accepts the result, it signs and dates this test which becomes the approved for printing ( BEATS ). This document then starts the work of the printer, the realization of the printing form and will be its reference frame (the standard to some extent).
He will guide the printer which will have to conform to “the image” of this BEATS throughout pulling.
Then comes “the pre-inking” which consists in beginning the impression slowly to let ink be distributed on the rollers, “to nourish” the strainer and to check that the image is printed correctly. This part of the pulling which is a phase of adjustment is destroyed, it is called the trowel paper.
As soon as inking is correct and after checking of the “bar of control” (element of measurement and quality control), one refines the result to be in conformity with the BLDG.
If the customer is present at pulling, it signs the “Good then To be rolled” (in its absence, the foreman or the driver takes up this duty).
Pulling itself can start and it is then the “follow-up of pulling”.
It is then necessary individually to recover each layer or each book and to finalize the product.
It is the work of completion called “shaping” which comprises several operations: folding of the book (to find the pages in the normal order of reading after the folding), old Massicot (to cut the document to the final format), Assembly of the books (by puncture, joining or fastening), Binding (in the case of Book S or re-examined of luxury) and distribution.
In the case of the Rotary S, the operations of folding, guillotining and even the assembly are often automated and carried out uninterrupted on the same machine.
The techniques differ somewhat if they are Magazine S, books, label S or the newspapers.
guillotining consists in cutting the sheets to the final format because one always works with a format of page slightly larger, this surplus called “cut” or “bad temper” ensures a clearer presentation of the image after guillotining.
French School of paper mill and graphic industries Site of the EFPG
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