The print industry

The print industry

hand printing

etching• Etching is the process of using strong acid or

mordant to cut into the unprotected parts of a metal surface to create a design in intaglio in the metal (the original process—in modern manufacturing other chemicals may be used on other types of material). As an intaglio method of printmaking, it is, along with engraving, the most important technique for old master prints, and remains in wide use today. In pure etching, a metal (usually copper, zinc or steel) plate is covered with a waxy ground which is resistant to acid. The artist then scratches off the ground with a pointed etching needle where he or she wants a line to appear in the finished piece, so exposing the bare metal.

linocut• Linocut is a printmaking technique, a variant of

woodcut in which a sheet of linoleum (sometimes mounted on a wooden block) is used for the relief surface. A design is cut into the linoleum surface with a sharp knife, V-shaped chisel or gouge, with the raised (uncarved) areas representing a reversal (mirror image) of the parts to show printed. The linoleum sheet is inked with a roller (called a brayer), and then impressed onto paper or fabric. The actual printing can be done by hand or with a press.

Screen print• Screen printing is a printing technique that uses a woven mesh to support

an ink-blocking stencil to receive a desired image. The attached stencil forms open areas of mesh that transfer ink or other printable materials which can be pressed through the mesh as a sharp-edged image onto a substrate. A fill blade or squeegee is moved across the screen stencil, forcing or pumping ink through the mesh openings to wet the substrate during the squeegee stroke. Basically, it is the process of using a mesh-based stencil to apply ink onto a substrate, whether it be t-shirts, posters, stickers, vinyl, wood, or other material.

• Screen printing is also a stencil method of print making in which a design is imposed on a screen of polyester or other fine mesh, with blank areas coated with an impermeable substance. Ink is forced into the mesh openings by the fill blade or squeegee and onto the printing surface during the squeegee stroke. as the screen rebounds away from the substrate the ink remains on the substrate. It is also known as silkscreen, serigraphy, and serigraph printing. One colour is printed at a time, so several screens can be used to produce a multi-coloured image or design.

woodcut• Woodcut—occasionally known as xylography—is a relief printing

artistic technique in printmaking in which an image is carved into the surface of a block of wood, with the printing parts remaining level with the surface while the non-printing parts are removed, typically with gouges. The areas to show 'white' are cut away with a knife or chisel, leaving the characters or image to show in 'black' at the original surface level. The block is cut along the grain of the wood (unlike wood engraving where the block is cut in the end-grain). The surface is covered with ink by rolling over the surface with an ink-covered roller (brayer), leaving ink upon the flat surface but not in the non-printing areas.

• Multiple colours can be printed by keying the paper to a frame around the woodblocks (where a different block is used for each colour). The art of carving the woodcut can be called "xylography", but this is rarely used in English for images alone, although that and "xylographic" are used in connection with block books, which are small books containing text and images in the same block. Single-leaf woodcut is a term for a woodcut presented as a single image or print, as opposed to a book illustration.

Lithography• Lithography (from Greek λίθος, lithos, "stone" and γράφειν,

graphein, "to write") is a method of printing originally based on the principle that oil and water do not mix. Printing is from a stone (lithographic limestone) or a metal plate with a smooth surface. It was invented in 1796 by German author and actor Alois Senefelder as a cheap method of publishing theatrical works. Lithography can be used to print text or artwork onto paper or other suitable material. Lithography uses simple chemical processes to create an image. For instance, the positive part of an image is a water-repelling ("hydrophobic") substance, while the negative image would be water-retaining ("hydrophilic"). Thus, when the plate is introduced to a compatible printing ink and water mixture, the ink will adhere to the positive image and the water will clean the negative image. This allows a flat print plate to be used, enabling much longer and more detailed print runs than the older physical methods of printing (e.g., intaglio printing, letterpress printing).

Mechanical

letterpress• Letterpress printing is a technique of relief printing

using a printing press. A worker composes and locks movable type into the bed of a press, inks it, and presses paper against it to transfer the ink from the type which creates an impression on the paper. In practice, letterpress also includes other forms of relief printing with printing presses, such as wood engravings, photo-etched zinc "cuts" (plates), and linoleum blocks, which can be used alongside metal type in a single operation, as well as stereotypes and electrotypes of type and blocks. With certain letterpress units it is also possible to join movable type with slugs cast using hot metal typesetting.

Gravure• Rotogravure (Roto or Gravure for short) is a

type of intaglio printing process, which involves engraving the image onto an image carrier. In gravure printing, the image is engraved onto a cylinder because, like offset printing and flexography, it uses a rotary printing press. Once a staple of newspaper photo features, the rotogravure process is still used for commercial printing of magazines, postcards, and corrugated (cardboard) product packaging.

Screen process• The fourth traditional type of printing, screen process,

includes silk screen and has special applications in the printing industry. Silk screen printing is a form of stencil printing, i.e., printing where the ink is applied to the back of the image carrier and pushed through porous or open areas. The image is on a piece of silk stretched on a frame and backed by a rubber squeegee containing ink. The nonprinting areas on the silk screen are blocked out, and the ink is pushed through the porous areas corresponding to the design; the process is widely used for posters and for printing on glass, plastics, and textured surfaces. Mimeographing is another commercial application of stencil printing.

digital

photocopying• Photocopying is where you make a photocopy of

and original image using a photocopier. There are many advantages for using this like making copies of the original for an office group or a school class. There are disadvantages such as anyone can copy any image and some of the text on the copy might be missing due to the drum on the photocopier.

Laser printing• Laser printing is an electrostatic digital printing

process that rapidly produces high quality text and graphics by passing a laser beam over a charged drum to define a differentially charged image. The drum then selectively collects charged toner and transfers the image to paper, which is then heated to permanently fix the image. As with digital photocopiers and multifunction printers (MFPs), laser printers employ a xerographic printing process, but differ from analog photocopiers in that the image is produced by the direct scanning of the medium across the printer's photoreceptor. Hence, it proves to be a much faster process compared to the latter.

inkjet• Inkjet printing is a type of computer printing

that creates a digital image by propelling droplets of ink onto paper, plastic, or other substrates. Inkjet printers are the most commonly used type of printer, and range from small inexpensive consumer models to very large professional machines that can cost tens of thousands of dollars, or more.

Desktop publishing• Desktop publishing (abbreviated DTP) is the

creation of documents using page layout skills on a personal computer. Desktop publishing software can generate layouts and produce typographic quality text and images comparable to traditional typography and printing. This technology allows individuals, businesses, and other organizations to self-publish a wide range of printed matter. Desktop publishing is also the main reference for digital typography. When used skilfully desktop publishing allows the user to produce a wide variety of materials, from menus to magazines and books, without the expense of commercial printing.