To understand printing, one must understand the various printing methods description used today to print a product. While there are many different printing methods used today, there are still four main methods:
Letterpress is the oldest and fastest diminishing method used today. Developed centuries ago by the Chinese it is still used to print newspapers, labels, etc. Its quality, however, is not that of the other main processes and tends to print mid to low quality. Letterpress printing is becoming less common as it is time-consuming to set up the loose type and make the plates, and the range of fonts and styles is limited.
Flexography is a newer printing process developed during the mid 1900’s. Flexography uses a relief image on thin, flexible printing plates made of rubber. Flexography can be used to print on materials such as cellophane, polythene and metallic films, so it is often used to print plastic shopping bags. It is also used to print newspapers and paperback books.
Left photo is a sample of a BOPP flexography polypropylene woven bag.
A Biaxially Orientated Polypropylene (B.O.P.P) film can be printed with a photographic quality and then adhered to a woven polypropylene bag, which means 3-layer structure: fabric, lamination, BOPP film. Bags for pet food, animal feed, rice, etc.
Gravure is another old printing process used to print packaging, magazines, wallpaper, gift wrap, etc. The major advantage of Gravure is that it can print very long runs due to its confi guration. Sear advertising, for example, can count into the millions of printed pieces. Unlike offset, Gravure uses a metal printing cylinder can handle these types of long jobs without wearing out the printing cylinder. Money and postage stamps are also printed using a form of Gravure (Intaglio).
Lithography was developed during the late 1800’s in Germany and has become a very popular printing process. Offset Lithography is used to print newspapers, magazines, advertising, business forms, direct mail, etc. Lithography is the most widely used printing process used today.
There are, of course, other printing methods such as screen, electronic, etc., but the four above mentioned processes dominate the printing industry today. This will, of course, change during the next 25 years as other technologies come into being.