Friday, January 17, 2020

Offset Printing History

1 History of Printing Presses Printing is a method of transferring an image to surfaces for the purpose of communication. A printing press is a mechanical apparatus for applying pressure to an inked surface resting upon a print medium. The invention of the printing press is considered as the most influential event in the second millennium revolutionizing the way people learn and communicate. Rubbings from stone inscriptions were an early reproduction method in which images were carved into stone, similar to the gravure process.The substrate, which was a thin strong paper, was moistened to make it soft . A kind of adhesive is placed on the surface of the stone. The paper is placed over the surface of the stone and a stiff brush is used to rub the paper over the stone and into every depression of the stone. Ink is applied over the paper after it was dried. The paper is peeled off from the stone and a reversed image within black ink was revealed. Stone rubbings were used to print books, especially religious texts and historic classics. Drawing materials include charcoal, inksticks, graphite and wax.Seal Printing and the Origin of Letterpress Printing The Chinese also used a method of reproducing images that is similar to our present-day rubber stamp method (Fig. 1:1) called seal printing. Before seal printing was invented, the Chinese used a receipt-like system to transact business. Two ends of a bamboo stick were written in duplicate for a particular business transaction. When the transaction was completed, the bamboo stick was broken and each member would receive a record of the transaction. For nobility, the emperor provided a token of jade.The jade was broken and one half was given to the subject and the other half kept by the emperor. A seal stamp made of clay eventually replaced the tokens. One method of seal stamping was to force an impression into a surface with the seals. The other method was to ink the seal and transfer the wet inked image to a substrate . Presswork and Bindery Processes 1 An early form of seal printing was the use of signet stones. These stones were used in Babylon and other ancient countries as an alternative for signatures and as religious symbols. These stones or devices consisted of seals and stamps for making images on clay.The stone, often located on a ring, was dabbed with pigment or mud and then pressed against a smooth surface to make an impression. Fig. 1:1. Chinese seal and print. Fig. 1:2. Chinese ink stick. Block Printing in China The Chinese developed a method of printing in the fifth century in which a wooden block was used to reproduce images on certain surfaces over and over again. Wooden blocks were made from coniferous wood, honey locust trees, jujube trees, boxwood, and date and pear trees. Each tree had advantages and disadvantages as far as printing was concerned.The coniferous wood trees had a problem of uneven printing because of resin that was impregnated in the wood. If delicate and fine l ine images in illustrations were required, the honey locust tree was used. For text, the soft boxwood was used, while the pear tree provided the best wood to use for various types of images, followed closely by jujube and date trees. Blocks were soaked in water for about a month after they were cut. If the blocks were needed in a hurry, they were boiled, left to dry, and then planed on both sides. Some printers used both sides of the blocks.The printer had to cut away all portions of the block except the image area (Fig. 1:3). All images had to be carved backwards so that when printed on a substrate, the images would appear correctly for reading. The wood carver had to be very skillful in carving text and illustrations backward. These blocks marked the invention of letterpress printing. The non-image areas of the block are below the surface of the form, and the image areas are on the surface of the form. The printing method was simple. Ink was rubbed on the surface of the form with a brush (Fig. 1:3).A sheet of paper was then placed over the form with gentle pressure so it could receive the images . A dry brush was used to press the sheet against the form. It must be noted that the original paper was so thin that usually only one side was printed. Because the paper was very translucent, blank sides of the printed sheets were placed back to back in publications. 2 Presswork and Bindery Processes Fig. 1:3. Chinese wooden block printing. Fig. 1:4. The Diampond Sutra. A color technique was developed during this time. Color separated blocks were carved and printed in register with other color-separated blocks and text as well.This was the first attempt at multicolor printing. An important invention in printing technology occurred during the Song Dynasty. It was the invention of movable-type printing. A commoner by the name of Pi Sheng used movable-type blocks for printing during the Qingli years (1041-1048) of the Northern Song. This invention ushered in an era of movable-type printing and is a significant milestone in the history of printing. This invention soon died in China because it was very complex. The invention soon found its way to Europe in the fifteenth century. Movable TypeAn alternate method of reproduction called movable type was developed in the eleventh century in China. This method was established well after the wooden block method, which came around the fifth century. Movable type consists of individual letters, characters, and symbols creating a language or an alphabet (Fig. 1:5). These elements could be used in the printing of one form, and then be taken apart and used to print other forms. The thousands of different characters in the Chinese language made the use of movable type cumbersome and slow. The Chinese writing system was a pictographic and ideographic method of communication.The Chinese alphabet system consisted of almost forty-thousand characters. Each character represented something in real life such as trees, animals, and pottery. Pi Sheng is given credit for the invention of movable type. He used clay and carved individual characters. The carved letters were put into fire to harden them. A metal frame with a mixture of wax was used as a base for evening out the surface of the type. The typefaces were set close to each other to make up a form of type. The entire block of type was then forced into the waxed metal tray and planed down with a smooth board after the wax was melted down in an open flame.Presswork and Bindery Processes 3 Pi Sheng reasoned that each type or character was to be used over and over again. One advantage of the movable type method is that characters could be deleted or inserted without throwing the entire form away. Fig. 1:5. Chinese movable type. Fig. 1:6. Movable type printed document. The Middle Ages in Europe Before 1450, the majority of books in Europe were produced by the arduous task of manuscript writing and recopying. The few exceptions were books that were printed by the wooden-block method, which was introduced into Europe by the year 1400. This slow, laborious process required skillful workers.Block printing was also used for illustrations in books (Fig. 1:3) and in the printing of playing cards. During this era, a period that saw little or no advancement in the arts or sciences became known as the Dark ages. This period was also marked by a lack of communication. Monks, who worked in monastery rooms called scriptoriums or writeries, produced the majority of books written during the Dark Ages. The religious scribes were responsible for the recording of history and the production of books, as well as most other intellectual activity during this period. The bookmaking trade was highly specialized.Books were elaborately decorated with colored initials, and they often displayed special gems, precious stones, and gold on their covers. Books were scarce and the average person could not afford them. In addition, most people could not read or write in Europe during this era. During the Dark Ages, books were highly illustrated, since this facilitated communication. Many illustrations were featured in religious books as well as on playing cards. These illustrations were engraved in wood or metal, inked, and impressed on the sheet, a process that required great skill. There is proof 4 Presswork and Bindery Processes hat blocks were exchanged between printers. Several illustrations appeared in different publications. The same images were often used to illustrate different subjects. Type and illustrations at first were printed in two separate impressions because they were produced at different heights. Over time, type and illustrations were produced at the same height. The Renaissance era, a period that was marked by an intellectual awakening, began around the thirteenth century. People began to study the sciences and the arts and to explore their environment. Many discoveries were being made, and people wanted to have kn owledge of new ideas.Fig. 1:7. Statue of Gutenberg. Fig. 1:8. Gutenberg style screw press. Fig. 1:9. The Gutenberg Bible. The Gutenberg Era (1397-1468) During the Renaissance, people experimented with methods for the faster reproduction of books. One result of these experiments was the successful use of movable cast type and a press in printing by Johannes Gutenberg (Fig. 1:7). The invention was revolutionary for several reasons. European languages, in contrast to those of Asia, were alphabetic. They consisted of relatively few characters, such as the twenty-six letters of English.This small number of different characters made the use of individualcharacter types (movable type) practical. Casting each character in quantity from a mold and using a press for printing permitted very fast reproduction of written materials. Through experiments and innovations, Gutenberg perfected the printing process before the famous printing of the bible. Each page printed had thirtysix lines per page. Later the lines per page increased to forty-two. Because of this invention, printing soon spread rapidly throughout Europe. Books became plentiful because they could be printed more quickly.Many persons could now afford books, and printing fulfilled the demand. Intellectual activity and learning began anew. Because of the impact of books on the culture of Europe at this time, printing became recognized as the art that preserves all the arts. The following reasons help to further explain the importance of the invention of movable type: 1. With movable type, a greater degree of accuracy was possible. 2. The supply of books increased greatly. Over twenty thousand volumes for one book could be produced in one year. Presswork and Bindery Processes 5 3. Because books were plentiful, they were affordable.They became readily accessible among all classes of people. 4. The invention of printing stimulated the desire for learning. The invention of printing, more than any other invention, was credited with bringing Europe out of the Dark Ages. 5. A standard alphabet was in place. Despite many languages on the European continent, thousands could share from the same invention. Presses were set up in Holland, France, England, and other European nations. 6. Gutenberg invented a press (Fig. 1:8) fashioned from a wine press. Ink pads, which were made of leather stuffed with wool or horsehair, were used to apply ink to the form. . The ink that Gutenberg used was have been made from linseed oils and lampblack. Later it was discovered that traces of lead, titanium, and copper were also used. Gutenberg could not use the India ink produced in China, because it did not print well from metal types. 8. Gutenberg’s own contribution was a punch and mold system for producing metal types. This method created the mass distribution of movable types for printing. Despite the accomplishments of Gutenberg and other European printers, we cannot forget the Chinese influences on their inve ntions.These inventions eventually made their way to Europe via explorers, who came back with startling discoveries, including paper, playing cards, movable type, block printing, image prints, and paper money. The printing trade was not profitable. Gutenberg himself did not become rich from his innovations and contribution to the world. The problem lay in the marketing of books in Europe during that time. Although the demand for books and other printed matter was great, methods to market and transport books needed to be developed. Early European Printers (Graphic Arts Procedures) 460 Strasburg, Germany †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. Johann Mentelin 1464 Strasburg, Germany †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. Heinrich Eggestein 1465 Subiaco, Italy †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. Conrad Sweynhem 1467 Rome, Italy. †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. Ulrich Han 1468 Basel, Switzerland †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ Berthold Rappel 1469 Venice, Italy †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ Johann of Speyer 1470 Venice, Italy . †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Nicholas Jenson 1470 Paris, France. †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ Michael Fibiger 1473 Nuremberg, Germany †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ Anthony Koberger 1473 Utrecht, Netherlands †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢ € ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ Gerardus Leempt 1473 Lyons, France †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ .Guillaume Leroy 1494 Venice, Italy †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. Aldus Manutius 1497 Paris, France †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ Henri Estienne 6 Presswork and Bindery Processes Fifteenth Century PrintingPrinting was a very important invention during the Renaissance era. The key to the invention of printing lies in the manufacturing of movable type. This technology had to be perfected in order for the printing process to be developed. A few inventors worked on the development of movable type. A punch of a particular type style and size had to be produced. This punch was used i n making an impression of the typeface in a mold. The mold was made from copper, which is soft enough to receive the impression from a steel punch, but durable enough to withstand the heat from the molten metal that was poured into it to produce the type.The punch itself had a reversed character, which was reversed into the matrix as a positive recessed character. A wrong reading character was produced from the casting of molten metal in the mold. The person that produced the punch was often the designer of the typeface. Fig. 1:10. Fifteenth century typesetting and type casting (Cary Collection). The term unjustified matrix or strike was referred to as matrix that was produced by depressing the punch within the copper. The term matrix is used after the copper with its impression is fitted within the mold for casting (Fig. 1:10).The goal in the casting of type was to produce type of equal height. This was necessary in order for printers to obtain an even impression with few difficult ies. The matrix and its fitting within the mold were the key factor in the controlling of the type height. This was accomplished by using the same mold throughout the manufacturing of a font. In addition to the type height, the paralleling or the side-by-side placement of the type was also important. If type were not produced on a square body, then it would not stand straight and would slant when locked together with other characters. Presswork and Bindery Processes 7Molds were made up of two parts and screwed together in a parallel adjustment. In this way the mold could accommodate matrix of varying size. During the hand casting process, a worker could face shrinking of type, uneven filling of the molten metal in the mold, and injury from the heat of the molten metal. The process was slow, but the type could be used for thousands of jobs. By the mid-nineteenth century, automatic methods replaced the manual methods of typecasting. Workflow in the Fifteenth Century The workflow in th e fifteenth century included composition, imposition, printing, and binding.In the composition stage, once the text was decided on to print, then the volume of copy was determined. Lines per page as well as the total number of pages for the job were determined. The printer would then know how much paper was needed for the job. The compositor set the type for the job using a composing stick. Every time the stick was filled, the lines were transferred to a metal tray called a galley. Pages were formed in the galley. Pages in the fifteenth century were arranged on large stones in printer spreads. Pages were enclosed by wooden pieces, which are called furniture.A metal frame called a chase surrounds all pages and furniture. To secure the form, locks or quoins were used. One page with no printing on the other side was called a broadside. Two pages were called a folio; four pages, a quarto; and eight pages, an octavo. A pressman pulled a proof sheet from the imposed form (Fig. 1:11). The proof was given over to a corrector and a reader. The reader read the original copy as the corrector trailed along on the proof sheet to ensure that the text was the same. This process continued until all corrections were found and changed.Because of these continuous changes, no single copy of an early printed book is identical to any other. Fig. 1:11. Fifteenth century printing (Cary Collection). Paper was prepared the day before the actual press run. Piles of sheets each were set out, wetted, and allowed to stand overnight. This was necessary because the common screw presses of the time did not have enough power in them to force dry paper to evenly take the ink. 8 Presswork and Bindery Processes Two pressmen were involved in the printing process. One applied ink to the type, and the other pulled the bar and worked the paper.Pulling the bar required a lot of energy and printers would take turns in this process. Ink balls were used to applied ink to the form. These ink balls were ma de of leather pads, mounted in wooden cups and handles, and stuffed with wool or horsehair; they were then covered with a sheepskin pelt. Ink balls were inked, and ink was placed over the form in a rocking motion. A sheet of paper was then laid on the tympan. The tympan, paper, and frisket were folded together onto the form. The pressman then pulled the bar toward himself. This caused the turning of the screw, drawing the platen down and forcing the paper against the inked form.It sometimes took two pulls to print one form. The carriage was cranked out from under the platen. The tympan and frisket were raised, and the paper was removed. Sheets of paper were printed on the reverse side immediately while the sheet was still damp. Printing on both sides of the sheet is called perfecting. After the job was printed, the compositor cleaned the ink off the forms, unlocked the type, and distributed the type into the cases. Printed sheets were sent to a drying room and hung up in sets to dry . They were then piled into heaps on a long table and collated by signatures.Next they were folded once, pressed, and baled for delivery or storage. Fig. 1:12. Adams power platen press. Fig. 1:12a Early inking apparatus. Evolution of inking rollers. Fig. 1:13. Ink balls. Fig. 1:14. Ink brayer. Fig. 1:15. Inking rollers. Presswork and Bindery Processes 9 The Power Platen Press In 1830, Isaac Adams of Boston invented a press, which combined the advantages of the hand press and a press that could print larger forms. The platen on this press was stationary with the bed of the press rising to make contact with the platen to print.The form would be inked when the bed of the press returned to its lowest position. At this point the inking rollers would transfer ink over the printing form. A frisket was used to carry the sheet to the printing position (Fig. 1:12). The average speed of these presses was around 800 sheets per hour. Inking rollers evolved from a hand frame with two handles auto matically inking rollers, to the use of vibrating rollers to drive the rollers in the unit. An earlier method of inking employed a â€Å"roller boy† or an â€Å"assistant pressman†. Soon the inking apparatus (See Fig. :12a) was run by power, which was signaled by the action of the bed moving up and down. The Job Presses Job work consist of smaller work such as tickets, circulars, business cards and bills. This type of work became problematic for hand-press printing where the demand was in place for smaller, faster and more accessible presses. One of the first job presses was called the Adams press. This press did not meet the qualifications that were needed to run smaller job work. S. P. Ruggles of Boston introduced a series of presses in 1830. They were known as â€Å"card presses†.The card press was manufactured with a flat side on the side of a cylinder supported between side frames. A second flat surface known as the â€Å"platen† was directly across from the bed of the press. Rollers on the press, which traveled around the cylinder, did the inking. The largest press sheet on the press could accommodate a press sheet of 6† X 9†. Other notable presses include: The Albion Press of 1835 (Fig. 1:19), The Paragon Press of 1829 (Fig. 1:17), the Stanhope Press of 1816 (Fig. 1:20) and the Chandler and Price Platen Press of the early 1900s (Fig. 1:18). Harrison T. Chandler and William H.Price founded Chandler and Price Company in 1881 in Cleveland, Ohio. Chandler and Price manufactured machinery for printers including hand-fed platen jobbing presses, paper cutters, book presses, and assorted equipment. Fig. 1:16. Clymer-Columbian Press. Fig. 1:17. Paragon Press. 10 Presswork and Bindery Processes Fig. 1:18. Chandeler & Price Press. Fig. 1:19. Albion Press. Fig. 1:20. Stanhope Press. Many job presses came out with several improvements over the years. These improvements included: †¢ Larger press sheet sizes. †¢ Faster press speeds. †¢ Better synchronization of the bed and the platen. Improvement in the inking roller application. †¢ Better impression devices. †¢ Automatic feeding and delivery. The newspapers were printed on wooden hand presses operated by levers and screws. It was not until around 1816 that the new iron Columbian press came into general use. The Columbian press (Fig. 1:16), invented by George Clymer of Philadelphia, had, instead of a screw, a series of compound levers that multiplied the pull of the operator. All hand presses were slow. The forms had to be laid by hand and the inking of the form was notably poor and of uneven quality. Web Offset DevelopmentWith the nineteenth century came the addition of the steam-powered press, the cylinder press and the web press. An American inventor by the name of William A. Bullock (Fig. 1:32), patented the web press. The web press printed from rolls of paper rather than from individual sheets. This was followed by another Ame rican invention, the continuous roll press, devised by Richard M. Hoe. This device sped up the production of newspapers to around 18,000 newspapers an hour. In 1871 Hoe (Fig. 1:30) and company turned their attention to constructing a press that would feed a continuous roll of paper and print on both sides of the fed paper.They petitioned ink manufacturers for the development of fast drying inks. Paper manufacturers were asked to produce rolls of paper with Presswork and Bindery Processes 11 Fig. 1:21. William Bullock Web Press. Fig. 1:22. Web Perfecting Newspaper Press. Fig. 1:23. Turn bars Assembly on a Web Press. 12 Presswork and Bindery Processes Fig. 1:24. Web Press Infeed Section. uniform strength. But there were other problems that needed to be solved including the severing of sheets after printing and an accurate delivery of papers. Stephen D. Tucker, who was an employee of Hoe and Company, patented the gathering and delivery mechanism.This mechanism produced flat rapid deliv ery of printed sections. The web presses operated at speeds as fast as 18,000 impressions per hour. This finishing device was necessary for the production of â€Å"fold ready† products for immediate delivery by carrier or mail. The finishing steps were done â€Å"inline† or on the same piece of equipment. Initially equipment similar to the traditional folding machine was used. Conveyor belts would carry the sheet to right angle folding units, which were made up of folding rollers until the desired folded format was completed. Then in 1875 Stephen D.Tucker patented a rotating folding cylinder. This device folded the papers as fast as they were printed approaching speeds of 15,000 per hour. Paper enters from two rolls into two portions of the press. The web is printed (perfected) on both sides of the sheet and traveled towards the rotating folded cylinder. The sheets entered a triangular former, which folds the sheets at a predetermined place on center of the sheets. The sheets were then taken over a second cylinder, which gave it another fold. A knife then severed the sheet separating it from the web.The folded section traveled down a conveyor belt to be manually removed, wrapped and shipped Cylinder Press Invention William Nicholson received a patent for an idea for press in 1790 in which a form is to be placed on a cylinder over a flat bed. The substrate is fed between the bed and the impression cylinder to receive an image. The application of ink was done with rollers on this press. The rollers was composed of cloth covered with leather. Nicholson's envision for this press was far ahead of his time. Nicholson did not have a method for producing curved letterpress plates to fit around a cylinder.The securing of the plate for printing was another mystery at that time that would have to be figured out. In 1814, Frederick Koenig invented the first automatic press (Fig. 1:25). Frederick Koenig was a clock maker by trade. Koenig’s first press was actually patented in 1810. The entire bed moved laterally, and the form received ink from a set of inking rollers placed at one end of the press. The key to the automation of this press was the metal gripper finger, which in essence replaced human fingers for providing sheets to the press. Before this time, presses had been fed by hand.The automatic press was powered by steam and was used in printing the Times of London. It printed approximately 800 sheets per hour, an amazing feat in the 19th century and adequate for the population of that time. Thomas Bensley, a printer and Andrew Bauer a mechanic, assisted Koenig. They invented a press with a bed that moved laterally with the form and an impression cylinder that pressed the wet inked image on the substrate. The impression nip, or the area that prints at any given time, is very small on a cylinder press, resulting in a much better image transferred to the substrate.More importantly, this invention prevented many injuries and d amage to the press because operators were not in close contact with the moving parts on the press. Presswork and Bindery Processes 13 Fig. 1:25. Koenig’s cylinder press. Fig. 1:26 Hoe’s cylinder press. Fig. 1:27. Battery of cylinder presses. 14 Presswork and Bindery Processes Fig. 1:28 Advertisement of a cylinder press. Richard Hoe and the Rotary Press Richard Hoe (Fig. 1-30) was born in New York City. He went to work for his father, who manufactured printing presses. His father experimented with cylinder presses until his retirement in 1830.Richard carried on this work after his father retired in 1830. He invented the single cylinder press, which was capable of printing 200 copies per hour. Hoe also introduced the double cylinder press in 1844, known today as the rotary press. One cylinder carried the type to be printed while the other cylinder carried the paper and provided printing pressure so that the image could be transferred to the substrate. Rotary presses requ ires curve metal letterpress plates. The difficulty of making these curved plates slowed the acceptance and growth of rotary presses.Curved stereotype plates were accepted and used by 1870. The rotary press became the press of choice for newspaper reproduction, business forms, catalogues and magazines. A flying splicer was introduced for the continuous printing of publications without the need of stopping the press. This device changed the rolls by attaching a new roll to and expired roll. Hoe also invented an additional press in 1847 (Fig. 1-30), which featured a type form and four cylinders for carrying the sheets through the press. It is interesting to note that a boy, who fed sheets to the cylinder, also attended each cylinder.This press produces prints at the rate of 8,000 sheets per hour. Hoe is also credited with the invention of a web perfecting press. This press feeds from rolls of paper and is printed on both sides of the sheet. The presses were powered for the most part b y steam. Electric power took over in the nineteenth century as the main power source for presses. Presswork and Bindery Processes 15 Fig. 1:30 Richard Hoe (left) and his six rotary press (above). Fig. 1:31. Richard Hoe web press. Fig. 1:32. William Bullock. 16 Presswork and Bindery Processes Fig. 1:33. William Bullock’s rotary press.

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