What are the pressure printing
Pressure printing can be divided into letterpress printing, lithographic printing, and streak printing, each of which has its own characteristics. Throughout the ages, with the continuous improvement and innovation of printing technology, some printing technologies have been gradually replaced or eliminated, no matter what, every printing method has its glorious era. Biyin Bazaar today to talk about the once glorious pressure printing. Letterpress printing is characterized by the fact that the pictures and words on the printing plate are protruding and located on the same plane, and the concave blank part is not coated with printing ink. Letterpress prints have vivid ink colors and clear handwriting, which can be used on relatively inexpensive ordinary paper, and the paper loss rate is low. The disadvantage is that the plate loading and cushioning time is long, and the printing plate format is small; The quality of the picture is not as good as offset and photogravure plates, and lead alloys pollute the environment and are harmful to health. Therefore, after the 50s of this century, it is gradually replaced by other printing methods, and only the flexographic plate made of photosensitive resin as raw material can maintain its development trend in packaging printing and newspaper printing. Lithography originated from lithographing, which is characterized by the fact that there is no obvious difference between the graphic part and the blank part of the layout. However, the chemical properties of the two are different: the graphic part is lipophilic, and the blank part is hydrophilic. When printing, the layout is first wetted, and then the ink is applied to the graphic part. Due to the heavy and expensive lithographs, they were soon replaced by thin sheets of metal with a rough surface, and printed on a circular press. In 1905, Rubell of the United States invented indirect lithographic printing through blanket cylinder transfer, which is customarily called offset printing in China. The characteristics of stencil printing are: there are many fine holes in the graphic part of the printing plate, and the blank part is closed. The printing ink passes through the graphic part and adheres to the surface of the substrate. There are two common types of stencils: transcription and silkscreen. The transcription is simple and convenient, suitable for printing small quantities of documents and handouts, and has now been replaced by photocopiers. The screen printing equipment is simple, the plate making is convenient, and the ink layer with a thickness of 30 to 100um can be printed on the surface of different substrates, the color is bright and thick, the imprint is resistant to light and grinding, and can be accelerated by infrared or hot air or cured under ultraviolet radiation with UV ink. Therefore, it is especially suitable for the printing of small and medium-sized batches of various printed matter, metal signs, plastic products, ceramic decal paper, glassware and printed circuit boards, with a wide range of applications, rapid growth and broad development prospects. However, screen printing is not suitable for printing small text, color screen printing is prone to turtle lines, printing speed is diffuse, in the field of large-scale books and newspapers, it is difficult to compete with other printing methods. The above describes the pressures that have been printed throughout history, and we are certain of the contributions they have made.