What Is Offset Printing?
Offset printing is the most commonly used printing method today. Over 40% of all print jobs are carried out using offset printing.
Offset printing works in a simple manner. It uses three cylinders to transfer the image onto the substrate. The first cylinder is mounted with the printing plate. The image on the printing plate is ‘right’ reading or written with the right side up. The first cylinder is inked and the image transferred or offset onto the second cylinder, which is mounted with a rubber blanket. The image on the second cylinder is thus reversed or becomes ‘wrong’ reading. Finally the image is transferred from the blanket cylinder onto the third cylinder or the substrate. The substrate is mounted on the third cylinder also known as the impression cylinder. The image once again is reversed and becomes ‘right’ reading or right side up in the final printed version.
A unique characteristic of offset printing is that the image and non-image areas are on the same surface level. The printing method uses the chemical fact that oil and water do not mix to print from a single surface level. In fact, offset printing acquired this method from lithography and thus it is often referred to as litho offset printing as well.
Offset printing is the most commonly used printing method today. Over 40% of all print jobs are carried out using offset printing.
Offset printing works in a simple manner. It uses three cylinders to transfer the image onto the substrate. The first cylinder is mounted with the printing plate. The image on the printing plate is ‘right’ reading or written with the right side up. The first cylinder is inked and the image transferred or offset onto the second cylinder, which is mounted with a rubber blanket. The image on the second cylinder is thus reversed or becomes ‘wrong’ reading. Finally the image is transferred from the blanket cylinder onto the third cylinder or the substrate. The substrate is mounted on the third cylinder also known as the impression cylinder. The image once again is reversed and becomes ‘right’ reading or right side up in the final printed version.
A unique characteristic of offset printing is that the image and non-image areas are on the same surface level. The printing method uses the chemical fact that oil and water do not mix to print from a single surface level. In fact, offset printing acquired this method from lithography and thus it is often referred to as litho offset printing as well.
Types Of Offset Presses
Offset presses are primarily of two types:
Sheet-fed Offset Printing Press: In this kind of offset press the printing is carried out on single sheets of paper as they are fed to the press one at a time.
Web-fed Offset Printing Press: In this kind of offset press the printing is carried out on a single, continuous sheet of paper fed from a large roll. The sheet is then cut into individual sheets of desired sizes.
There are many more differences between the various types of offset presses.
The Offset Printing Process
The offset printing process requires a fairly large investment in equipment and set up. However, once the infrastructure is in place, offset printing itself is relatively inexpensive. There are many things to know about the offset printing process from creating the artwork to operating the press and binding.
Applications Of Offset Printing
Offset printing invades every aspect of our lives from influencing education through the printing of books, periodicals and other reading material to the packaging industry by creative printing of packages for consumer goods. The many applications of offset printing would be difficult to put down but suffice to say that the world would be a much less fun place to live in without offset printing.
Thus, offset printing is the printing technique that has made newspapers possible, books affordable and marketing and promotion the weapons of the common man.
Applications Of Offset Printing
The next time you read a newspaper, browse through a magazine or even glance at brochures in the mail spare a thought and think about what it takes to print and publish such vast amounts of information and graphics. Offset printing is responsible for almost 40% of all printed material that you see around you.
It would be difficult to create a complete list of the applications of offset printing. If something needs to be printed, offset printing can do it. Here are some examples of the applications of offset printing to get you thinking on the entire scope of offset printing.
Newspapers are probably the most visible example of offset printing that is a part of everyone’s life. Every morning you are greeted with an application of offset printing. It is to the credit of the speed of offset printing that such high volumes can be generated every single day.
Books are another application of offset printing without which life would simply not be the same. Whether for education or entertainment, books are the life source of many a people and they have offset printing to thank for making books affordable.
The law too has to thank offset printing for making the legal process more streamlined. Large volumes of legal forms and documents are printed using offset printing.
Businessmen would be lost without offset printing. Important financial data is at their fingertips thanks to offset printing.
The marketing and advertising industry would regress by centuries if it weren’t for offset printing. The entire direct marketing industry would perish. Offset printing is used for printing flyers, brochures, PR material and a host of other marketing applications.
Thus, offset printing affects every aspect of our lives – social, economical, educational, professional, legal and even our relationships! Hallmark just wouldn’t have the same effect without offset printing now would it?
Components and Types Of Offset Presses
Offset printing is an indirect printing process. A typical offset press generally has three cylinders – the printing plate cylinder, the rubber blanket cylinder and the substrate or impression cylinder. There are several other components that make up an offset press. All these components work together to produce the printed substrate.
Components Of A Typical Offset Press
A typical offset press is made of a feeding tray to supply paper to the feeding system, a set of cylinders to create the printed image, a roller train to ink the image areas and dampen non-image areas of the image and a system for removing the paper from the printing system.
Feeding System: The feeding system refers to the mechanism that feeds paper or any other substrate to be printed upon into the press for printing. In sheet fed presses the substrate is stacked together in a tray. Vacuum devices called sucker feet pick up each sheet of paper from the stack and feed it into the press one at a time. For web fed presses a rollstand is used. A large continuous roll of paper is mounted onto the rollstand that maintains the appropriate amount of tension while feeding the paper to the press.
Printing System or Cylinders: Offset presses generally use three cylinders. The plate cylinder, the blanket cylinder and the impression cylinder. The plate cylinder is mounted with the led plate on which the image is drawn right side up. This image is transferred onto the blanket cylinder in reverse or wrong side up. The blanket cylinder then passes the image onto the impression cylinder – once again right side up.
Inking System: The inking system in offset presses is made up of a fountain, which holds the ink and a set of rollers known as the roller train. In general, the more rollers in a roller train the better the press. A roller draws ink from the fountain into the roller train. The ink is milled to the required thickness and brought to the final rollers in the roller train known as the form rollers. These apply the ink to the plate.
Dampening System: The dampening system also consists of a fountain and a set of rollers. These apply the fountain solution to the plate to keep the non-image areas from getting inked.
Delivery System: This is the mechanism that collects the printed substrate from the press and assembles it in a neat manner. In sheet fed presses the printed sheets of substrate are carried from the press into a tray where they are neatly stacked. In web fed presses there are two options for delivery systems. A roll-to-sheet press cut the continuous substrate into single sheets after printing as per specifications. A roll-to-roll press carries the printed susbtrate from the press to a rewinding unit where the substrate is would onto a spool.
Types Of Offset Presses
There are two main kinds of offset presses:
Sheet fed offset press: In a sheet fed press the substrate is fed to the press in single sheets and each sheet is printed individually. The printed substrate is then collected in a tray and stacked neatly. Sheet fed presses often give better quality than web fed presses. However, the latter can be more economical for larger runs.
Web fed offset press: In a web fed press the substrate is fed to the press from a continuous roll. After printing the roll is either rewound onto a spool or cut into sheets depending on the requirements. Web fed presses print at a much higher speed than sheet fed presses and hence are more economical for larger runs.
Thus, the initial investment in an offset printing press can be fairly high but the actual cost of offset printing turns out very economical.
The Process Of Offset Printing
Offset printing refers to the printing technique where ink is applied to a metal plate that is etched with images, then transferred to a rubber plate and finally imprinted on the substrate. That is just a small part of the entire offset printing process. The entire process involves the pre-press production, the actual press run and the bindery.
Creating The Artwork
The creative process can involve any number of people from graphic artists, cartoonists, copywriters, and creative directors to illustrators and editors. It is very important to proofread the entire artwork before sending for final printing. The artwork is generally sent in a digital format either on CD, floppy or via the Internet.
The Printing Process
Offset printing is something almost every commercial printer is involved in. However the quality of offset printing often depends on the experience of the printer and the equipment used. There are three main steps in the printing process.
Pre-press Production: Once the artwork has been approved it needs to be converted to film and plates for printing. The film negatives are created from the digital files. The images from the negatives are then transferred onto the printing plates much like developing photographs. Different materials from paper to aluminum are used to produce plates. Each of the four colors – C, M, Y and K has a separate plate.
The Press Run: Offset printing works on the principle that oil and water do not mix. The press run or offset printing process or offset press is made of the feeding system, the printing system or three cylinders, the inking system and the delivery system. There are different types of offset presses as well that are used for the press run. The press run starts with a blank substrate and ends with a printed substrate.
Bindery: The bindery is the stage when the printed substrate is given the final treatment before it is declared ready for use. If the substrate is in the form of a large roll, it is cut into required size sheets. It is glued, bound, stapled and collated before being shipped to the final destination.
Thus, the offset printing process involves a number of stages and the hard work of many professionals. It is no wonder that offset printing is a large industry in itself and the applications of offset printing are increasing day by day.
Learn More About Printing:
Shopping for Professional PrintersToday your professional printer has a wide rage of technology and options to incorporate into your projects.
Create Postcards Using Offset PrintingOffset postcard printing is the traditional style of printing postcards, and even with all the modern state-of-the-art printers, is still widely used today.
Comparing Digital and Offset PrintingMany feel that digital technology will someday replace offset printing. It is true that technology is constantly improving, which also improves the quality of digital prints.
Varnishing Increases Profitability of Your Printed MaterialWhether the effect you want to achieve is a glossy, dull, or tinted appearance or if you wish to play one type of varnish against another your finished produce will be enjoyed for its uniqueness in print, design, and style.
PRINTING HISTORY
Any comments, questions??
SOTA: The Society of Typographic Aficionados
exists to increase public awareness and appreciation of the art and history of typography and its function in creating beautiful and successful communication. To this end SOTA sponsors a conference for members and nonmembers alike and publishes a variety of publications related to its activities. The society, soon to be a non-profit cultural foundation, was founded in 1997 by Bob Colby.
The Virtual Museum of Printing-Press
The Virtual Museum of Printing-Press is a AMI-Associação Museu da Imprensa (The Press Museum Association) project. We intend to diffuse the sector's history, to show the patrimony, to suggest inteneraries, to collect information concerning press and graphic arts museology, and to give/receive news. From the millenary writings to the nowadays electronic edition, passing by the Gutenberg typography, by lithography, photogravure, rotting printing-press, by through the times free and silenced newspapers, etc, etc., there is a world to be discovered with the new virtual reality. This world begins with this virtual project and can end in each of the real press and graphic arts museums all over the five continents. By the Gutenberg's time people sailed on the oceans - by "oceans never ever navigated", as the portuguese poet Luís de Camões wrote; nowadays we virtually navigate all over the world. This Virtual Museum intends to be a cyberspace with a global participation of institutions and people involved, or people just interested, on press and graphic arts matters. For all this reasons, all collaboration will be appreciated
Center for the History of Print Culture in Modern America
A joint project of the State Historical Society of Wisconsin and the University of Wisconsin-MadisonFor centuries Americans have been informed by print. All people in America's multicultural and multi-class society have used or been influenced by print, sometimes for common purposes, sometimes for different purposes. In recent years scholars from a variety of academic disciplines who are interested in studying this phenomenon have begun to refer to it as "print culture history." The history of print culture in the United States since 1876 has not received the attention it deserves. The scholarly work produced is fragmented by discipline and geography. Madison's combination of academic strengths and library resources (e.g., the Cairns and Little Magazines collections at memorial Library; the extensive periodical and newspaper collections at the State Historical Society Library) present a unique opportunity to forge the new scholarship the field needs. The Center for the History of Print Culture in Modern America in Madison, Wisconsin, attempts to fill this gap. Its objective is to help determine the historical sociology of print in modern America in all its culturally diverse manifestations. As a joint program of the State Historical Society of Wisconsin and the University of Wisconsin-Madison, established in 1992, it is designed to: * encourage the interdisciplinary study of print culture history on campus and serve as an interdisciplinary focus for research on print culture by scholars of modern America throughout the country from such diverse fields as literature, journalism, publishing, education, reading and library history, economics, sociology, the history of science, and political science and gender and ethnic studies; * facilitate research into the valuable print culture research collections owned by both library systems which focus on newspapers, periodicals, advertising, printed ephemeral materials, and books (including school and college texts, children's literature, trade and scholarly monographs, and mass market paperbacks); * stimulate research in the print culture collections of groups whose gender, race, occupation, ethnicity and sexual preference (among other factors) have historically placed them on the periphery of power but who used print sources as one of the few means of expression available to them; * function as a clearinghouse for information on print culture research and scholars concerned with the history of modern America; * work with the Center for the Book at the Library of Congress and with various state centers for the book on joint programs, exhibits, colloquia, symposia, and publications; * raise funds for scholarships, fellowships, and lecture series to assist the study of modern American collection reflecting the history of print culture; * aid in the development of an international perspective on print culture in modern America, including the reception of American publishing abroad, and foreign publishing in the United States, both in English and other languages. * the Center sponsors a monthly colloquium series, an annual lecture, and a biennial conference on themes related to print culture history since 1876.
William Hogarth and 18th-Century Print Culture
Islamic Calligraphy with Mohamed Zakariya
This exhibit consists of a transcript of the film, Islamic Calligraphy with Mohamed Zakariya, with interleaved images (in GIF format) drawn from the film, as well as associated Quicktime audio/video clips. Mohamed Zakariya speaks throughout the film; the text faithfully represents his own words, with minor grammatical adjustments.
PRINTS & PRINTMAKING
The history of artists' prints and printmaking, via the preparation of an interactive student tutorial package; this project currently has 2,800 digitized images, ranging from the 15th century to the 20th century, from religious to secular, from "high art" to popular, and also including sections on techniques, using extreme closeups of the prints selected. All images are in JPEG format, for compactness, although many of the prints are monochrome. The collection (eventually to be joined by relevent art-historical texts and commentaries) will shortly be written to a CD-ROM, and front-ended by an Amiga or Macintosh - although we are considering XMosaic as a possible delivery system.
HISTORY OF THE VATICAN LIBRARY
"Rome Reborn: The Vatican Library and Renaissance Culture." This book, published by Yale University Press, serves as catalogue for the exhibit at the Library of Congress, which will present for the first time outside of Rome a selection of objects from the Vatican Library's remarkable collections. Although the excerpts below mention the book in particular, they also provide a good introduction to the exhibit itself, as presented both at the Library of Congress and through computer networks.
The Digital Catalogue Project
Bibliographical research is both inductive and positivist, and as a consequence it relies heavily upon the availability of abundant evidence. This project aims to create a model archive for the storage and circulation of material evidence concerning the printing industry in late Tudor and early Stuart London. All images stored in this archive are freely available for scholarly use, and source document information is included in the header of each image. For publication permissions or any other inquiries concerning the Digital Catalogue project, please contact:David L. GantsInstitute for Advanced Teechnology in the HumanitiesAlderman LibraryUniversity of VirginiaCharlottesville, VA 22903mailto:dlg8x@jefferson.village.virginia.edu
The Hall of Printing and Graphic Arts
The Hall of Printing and Graphic Arts features tools and equipment of the printing trades, a printshop and post office of about 1800, a printshop of 1865, a newspaper shop of the 1880s, and a foundry from the mid-19th century. Just after the turn of the century, American inventors Ira Rubel and the brothers Charles and Albert Harris independently developed offset printing, a technique widely used today. A Rubel offset press of 1905 and a Harris press stand near one end of the hall. The same platform holds a half-scale model of the Nicolas-Louis Robert papermaking machine, recently built from his drawings of 1800. Modern papermaking machinery is based on Robert's concept. In the printmaking corner, exhibits describe the techniques of etching, woodcut, lithography, photoengraving, collotype, and other processes. The displays features many fine old master and modern prints. Around the presses and prints, the graphic arts come to life in four shops: three print shops and a typefoundry. The typefoundry is an 1850s recreation where demonstrations show how type was created mechanically or by hand. A page from a Bible printed in the 15th century by Johannes Gutenberg, the inventory of printing with moveable type, adorns the wall outside the shop. Ranging down the wall from the typefounding shop is a row of typesetting machines beginning with American inventory Ottmar Merganthaler's Second Band Machine of 1885 and a Blower Linotype of 1890. Both were precursors of his famous Linotype machine, which revolutionized the printing industry by allowing typesetters to cast entire lines of type without much more effort than striking the keys of a typewriter.
NANCY NEALE TYPECRAFT
welcomes You to the wonderful world of antique Printing Memorabilia. NANCY NEALE TYPECRAFT has the largest Collection of Antique Printing Memorabilia in the world in private hands. It's the "Ultimate Collectible" if you're interested in antiques, crafts, printing nostalgia.
GUTENBERG MUSEUM
Mainz, Germany: Very nice museum worthwhile visiting in the attractive town of Mainz. Has a beautifull copy of the famous 42 line bible by Gutenberg. Website is German language only, but has nice images. (" Bis ins Medienzeitalter mit Bilder und Nachrichten in atemberaubendem Tempo ist dieser Name ein Begriff geblieben. Das gleichnamig Museum mitten im Stadtzentrum ist einne Hommage an den Erfinder der Druckkunst, seine weltberühmte 42zeilige Bibel eine der Kostbarkeiten des Museums.")
AMERICAN PRINTING HISTORY ASSOCIATION
encourages the preservation of printing artifacts and source material for the printing history, as well as the development of museums and libraries to house them. APHA is especially but by no means exclusively interested in American printing history and is actively encouraging development of regional chapters.
THOMPSON CONSERVATION LABORATORY
specializing in the restauration of medieval and renaissance books, art on paper (including Asian screens and scrolls), and more. The lab conducts condition surveys, performs scientific analysis, and provides a reference service, based on a 4,000 volume research library.
Science Museum Galleries Printing and Papermaking
The development of printing from clay tablets to the modern press. A range of mechanical presses; sections on typesetting by hand and machine, printing pictures and making paper, pens and pencils, typewriters and duplicators.
MANUTIUS:
ALDUS PIUS MANUTIUS
Publisher of Renaissance Venice. Large site to celebrate the 500th anniversary of the publisher's first dated work published in Venice in 1495. Biography, Editions, Book production during Aldus' lifetime, Type, Lineages, Scholarship, Status of the Aldine book, Aldus bibliography.IN AEDIBVS ALDI, the legacy of Aldus Manutius and his press. In February 1496, Aldus published an essay by Pietro Bembo. The type used is this publication became so famous that it influenced typeface design for generations.--------------------------------------------------------------------------
SOCIETE DES ANCIENS TEXTES FRANCAIS
tres nombreux textes francais de Moyen-Age...imprimes a petit nombre sure beau papier....
TYPSESETTING HISTORY
a Capsule History of Typesetting and HISTORY BUFF'S HOME PAGE (This page is for anyone that wants to learn more about journalism, printing and publishing history as well as American history in general. Contains extensive reference library covering 17 different categories ranging from the 16th century to the American Civil War to the story of Bonnie & Clyde. Included are links to other history and journalism related sites.)
PRINTING AND PRINT CULTURE
Media History, with many links to Books and Publishing, Authors and Publishers, Print Culture in the Renaissance, and Copyright laws.
THE HISTORY OF PRINTING
this documents traces the development of the printed book. With many thumbnails and links. A really fantastic site on this subject!! A mint example of how the electronic media can and should be used to "transport" information.
TYPESETTING HISTORY
a capsule history of typesetting. Textfile by R.J.Brown.
PRINTING: HISTORY AND DEVELOPMENT
About the technological roots in China (paper), Gutenberg and the Historical Moment in Western Europe, Print and modern thought, Print in the U.S., Advances in technology. Many related links.
History of the Book at Oxford
The information provided in these pages has been primarily taken (with permission) from the Teaching, Resources and Research in the History of the Book at Oxford newsletter being collated by Professor IWF Maclean of the European Humanities Research Centre in Oxford. Once completed, the newsletter will be circulated freely to all those at Oxford interested and involved in the History of the Book.
LETTERPRESS PRINTING
textfile on the history of printing. With a few links to related sites.
PRINTING PRESSES IN THE GRAPHIC ARTS COLLECTION
National Museum of American History. Catalog of the exhibition covers printing apparatus from presses to rubber stamps, as well as some documentary material relating to presses. The press collection has its greatest strength in wooden and iron hand presses of the eighteenth and nineteenth centuries, with some unique and important specimens in this area. The catalog explores the history of the do-it-yourself pinting movement that in the late 19th century swept up many American boys, including Jesse Grant in the White House.
THE FRIENDS OF THE MUSEUM OF PRINTING
A museum not yet to be visited..The 'Friends' are dedicated to the founding of a Printing Museum devoted to the graphic arts that will be a legacy for future generations. The museum will house the world's largest collection of historic and rare letterpress and offset printing equipment. This new museum will provide printers, craftsmen, and printing scholars an opportunity to bring the story of printing, specifically American printing, to the public.
THE PENNY MAGAZINE
published from 1835 (over 250 issues) every Saturday for the British working class. Now avaliable on-line. Articles on subjects of general interest, some poetry, and a few illustrations in each issue.
The Williamsburg Imprints Program
The Williamsburg Imprints Program (WIP) is a colonial American studies project based at the Colonial Williamsburg Foundation in Williamsburg, Virginia. The focus of this program is the material culture of printing as it was practiced in Virginia before 1781. The influence of printing on 18th-century American culture, government, and the Revolution was enormous. While a considerable amount of research has been done in this area, much of it excellent, the study of colonial printing has been handicapped by the lack of specific data. Where did these printers get their type and paper? How many people worked in these shops? How did 18th-century American printers perform their work as compared to their European counterparts? The purpose of the WIP is to answer these types of questions through the bibliographical analysis of the books, newspapers, and ephemera which survive.
WILLIAM CASLON
An empire of typefounding. William Caslon's work has long been associated with Colonial American printing and letterpress printing in general. It was chosen as the exclusive face for the Williamsburg Printing Office in the 1950's and remains the house face in demonstrations in front of the public today.
JOHANNES ROLU and JAN ROMAN
Little is known of these two founders from the low countries. Comparisons of their known specimens to type in John James' inventory prove that much of their work purchased by James as he toured the Netherlands for type moulds. It is interesting to note that Rolu and Roman also collected this kind of equipment as some of the decorative types found in their specimen sheets and consequently used in Williamsburg date from the late 1570's.
