Have you ever thought What Is Offset Printing? If you want to know more detailed about offset printing process, here is short description of it.
What is Offset Printing?
Offset printing is a Printing method in which ink is transferred under pressure from the printing plate on the intermediate surface of an elastic rubber blanket, and from it onto paper or other print material.
Offset printing is currently the most common method of printing. Using offset printing it is possible to produce almost any printed products, from business cards to large format Posters.
Compared with other types of printing, offset printing is characterized by high clarity and brightness of the applied image. This method can print any products with any ink. In addition, you can print special colors – “silver”, “gold” and use lacquers. For offset printing any types of paper is suitable – newspaper, cardboard, plastics in a wide range of thicknesses.
What is Offset Printing Machine?
All offset printing machines, with small modifications, use the same technological principle: from the flexible printed forms, which are fitting the cylinder (also called “intermediate offset link”), the paint is transferred under pressure onto the elastic surface of the rubber cloth, and from it to the paper or other printed material. In printed form printing and whitespace elements are on the same plane as a result of the output image is essentially flat, and has a selective perception of oily ink and dampening solution – water or an aqueous solution of weak acids and alcohols. Before applying the ink on the printing plate we apply the dampening solution on it. In the process of printing a form alternately is soaking with aqueous solute and rolling up the paint and then introduced under pressure into contact with the surface of the rubber plate, and the plate – in contact with the paper. The result is the imprint on paper.
Offset printing machine for printing in several colors has a separate printing unit for each color. When you print, paper is sequentially go through each section. If the machine has a smaller number of sections than the colors should be used to obtain the required color impression, it runs several times with the change of the intermediate colors.
Printing plates for offset printing are made on thin sheets of metal (aluminum or zinc, 0.4-0.8 mm thick) through the creation of various films with molecular surface properties, stable sensing moisture or paint. These forms are called monometallic. There are also forms on polymetal plates of 2 materials with different molecular properties of the surface: copper to create a sustainable printing elements and nickel (or stainless steel) – for whitespaces.
Despite a difficult preprinted preparation, which takes a long time, the very process of offset printing is fast enough, so benefits of large print runs of offset are undeniable.
Positive aspects of offset printing:
- High print quality.
- Ability to print on any type of paper and the use of any kind of finishing.
- Print long runs in a relatively short period of time.
- Reduction in the cost of printing for large print runs.
Offset printing problems:
- Continuous preprinted preparation.
- No profitability printing for small print runs due to the high cost of preprinted preparation.
- Impossibility of data personalization and numbering of copies.