Rotary Printing

Within this class of printing there are three different major methods, and these are: offset lithography, rotogravure and flexography. In this post I will research a little further into these processes and will hopefully in the future find an example of each one with a Mexican twist.

Offset Lithography, one of the most common ways of creating printed matter. A few of its common applications include: newspapers, magazines, brochures, stationery, and books. There are many different pros and cons to this process, a few of which are listed below.

Pros:

• High image quality, produces sharp and clean images and type more easily than letterpress.
• Quick and easy production of printing plates.
• Longer printing plate life than on direct litho presses because there is no direct contact between the plate and the printing surface.
• Cost, the cheapest method to produce high quality printing in commercial printing quantities.

Cons:

• Inferior image quality compared to rotogravure or photogravure printing.
• When developed plates are not cared for properly they tend to become sensitive and quality deteriorates.
• Time and cost associated with producing plates and printing press setup. As a result, very small quantity printing jobs are now moving to digital offset machines.

Below is an example of offset lithography specific to Mexican design. It is a piece of promotional art from the 1968 Mexico Olympics.

Rotogravure, in this process the image is engraved onto a copper cylinder because, like offset and flexography, it uses a rotary printing press. The vast majority of gravure presses print on rolls of paper, rather than sheets and print everything from narrow labels to 4m wide rolls of vinyl flooring. One of the most interesting items this kind of printing is used for it banknotes.

Pros:

• Plates are made from copper and therefore are more durable, ideal for longer runs or tougher substrates.
• Puts down a denser coverage of ink, therefore prints usually last longer at highest quality.

Cons:

• All images, including type and "solids," are actually printed as dots, and the screen pattern of these dots is readily visible to the naked eye.

Flexography, is basically an updated version of letterpress that can be used for printing on almost any type of substrate including plastic, metallic films, cellophane, and paper. It is widely used for printing on the non-porous substrates required for food packaging.