The project has explored the changing nature of the printing industry through the 20th century, and these are the main print processes that we have covered.
In letterpress printing, an artisan printing technique that has been around for hundreds of years, a surface with raised letters (typically, metal type; other possibilities include carved wood or stone blocks) is inked and pressed to the surface of the printing substrate to reproduce an image in reverse.
Silkscreen (or serigraphy) is a sophisticated stencilling technique for surface printing. It also has the advantage of being achievable at low cost and can be fast to implement. A design is cut out of paper or other thin, strong material and then printed by rubbing, rolling or spraying paint or ink through the cut-out areas. Screen printing inks can be used to work with a variety of materials, such as textiles, ceramics, wood, paper, glass, metal and plastic. Silkscreen was used commercially particularly from the 1960s but there are now very few silkscreen businesses left.
Offset lithography (often known as litho) is a method of mass-production printing in which images on metal plates are transferred (offset) to rubber blankets or rollers and then to the print media, usually paper, which does not come into direct contact with the metal plates. In the 1960s offset litho began to be preferred by many printers over letterpress due to its
speed and relative ease of use, and gradually it came to be used much more widely. Although the technology for designing artwork and making the plates is now digital, the presses themselves have not changed very much in recent decades.
Foiling and stamping
Foil blocking (or hot foil stamping) is the process of applying metallic or pigment foil to paper or card, where a heated die is stamped on to the foil. This makes it adhere to the surface and leaves the design of the die on the paper. Foil blocking is still often used to highlight a product as premium or category-leading, with pastels or metallics, using holograms, embossing and de-bossing, lamination, whether on business cards, stationery, packaging or brochure covers.
Finishing is a term that covers any processes performed after the ink has been applied to the paper and/or the paper has come off the machine. These include binding – fastening individual sheets together with perfect binding, saddle-stitching, spiral/ coil binding – and decorative processes such as diestamping, embossing and debossing and laminating. Other finishing processes include collating sheets into sequences; cutting and trimming paper to the desired size along crop marks; and scoring, making a crease for better-looking folding. Many printing firms had inhouse finishing sections, and would bind, stitch and fold the printed matter in a separate department.
Digital technology has gradually transformed the printing industry in many ways, not only through digitally transmitted information replacing many forms of printed matter and digital presses allowing the production of cheap and small print runs, but also the whole process of design and plate production taking place on computers. Although this has had an impact on many firms who were unable to keep up with changes, many others have managed to adjust to new technologies and maintain a connection with local customers who still need a bespoke service.