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 line 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...