What is Offset Printing?

While personal computers and mobile devices are continually providing us with a large part of our information intake; printed products are still playing a very important role in life. Good old books, brochures and magazines are still here. The products of the print industry are widely used in our everyday life, and the most commonly used printing technique for making these products is Offset Printing.

On a standard printing press, an image is transferred from a special plate to the desired print surface. In Offset Printing an additional roller covered with rubber (called an offset roller) is added to the process. This roller helps to print a direct image instead of mirrored one (as is the case with standard presses), and slows down the wearing out of the printing plate, because the plate has no direct contact with the service. This technique is used in combination with the lithographic process that is based on the repulsion of oil and water. It employs a flat image carrier which attracts ink from ink rollers to special printing areas, and the non-printing areas attract water instead. Today offset printing is the most widely used technique in commercial printing.

History of Offset Printing

While the first Offset Printing press was invented in 1903 by Ira Washington Rubel, the history of Offset Printing can be traced up to the first lithographic press machines invented in 1785 and seriously modified in 1880 (when rubber was added as printing surface). Even Johannes Guttenberg, the inventor of mechanical printing press had some ideas about an offset roller, but it took more that a century for this brilliant idea – actually installing this additional roller covered with rubber surface to slower the wearing out of the main roller surface and receive a direct image instead of mirrored image when printing – to materialize.

Offset Printing was also independently invented by Charles and Albert Harris. They created the basic method that was later widely used in the printing industry (and is still used by the way). They added a metal plate and also added the water and ink rollers to the typical printing press, basically creating the modern Offset Printing.

Why People Use Offset Printing

Offset Printing is generally the best solution if you need to print large amounts of pages. For amounts of over 500 copies, offset printing can be very cheap and with good image quality. This type of printing has many advantages when compared to other methods, for example the letterpress.

The quality in offset printing is very consistent. Rubber blankets used in Offset Printing conforms to the texture of the printing surface, and as a result the final images will be very clean and sharp. The production of printing plates for this type of printing is quick and easy. The life of the printing plates is also longer than in direct lithographic presses. Due to the additional offset roller, there is no direct contact between the plate and printing surface; if the whole system is developed and optimized properly, the plates can exceed the lengths of a million impressions. Also the offset printing process is very cheap; because offset printing presses print in massive quantities, most of the cost goes into preparations of the printing machine for the first sheet. For any additional sheets you will pay only for the paper and ink

Offset Printing Q&A

• What are the preferred amounts of copies for this type of printing?
  Offset printing is most suitable for amounts of more than 500 copies.
• What is the image quality of Offset Printing?
  The image quality is way better than in letterpress or other types of printing, only the rotogravure or photogravure printing methods have more advanced printing quality.
• Are there any disadvantages of Offset Printing?
  Yes, due to chemical oxidation the anodized aluminum printing plates can become sensitive and print in non-image/background areas, but this can happen only if the plates are not cared for properly.
• Can offset printing be used on other materials?
  Yes, you can use it on wood, metal, cloth, leather and rough paper.
• What is the usual price of Offset Printing?
  You’ll have to check it in your nearest printing factory, just google your neighborhood.

Conclusion

Offset Printing is a brilliant modification idea that has been serving the print industry for over a hundred years. It is easy and cheap, produces good quality images, and extends the servicing time of the printing surfaces. This is the best optimized solution for printing large amounts of pages at once. Offset printing is the most widely used type of printing in the industry.

blog comments powered by Disqus