​5 basic steps in offset printing process

1. What is offset printing?

2. Steps of offset printing
​Offset printing was first applied back in 1903 by Ira Washington Rubel, followed by brothers Charles Harris and Albert Harris, who built an offset printer for the Harris printing company. These are the two fundamentals that make the strong development of this printing technology.
 
After many ups and downs, in 1950, offset printing became the most popular printing technique for the commercial printing industry. Besides, after many improvements have been made to the letterhead, ink, and paper, optimizing the printing speed and the lifetime of the letterpress layout, offset printing is now used in most industries.
 
So what is offset printing? And how does the printing process happen?

1. The concept of offset printing in packaging production

Offset printing is a printing technique in which ink-stick images are pressed onto rubber sheets (also called offset sheets) and then pressed onto paper surfaces. When used with lithography, this technique prevents water from sticking to the paper with the ink. Offset printing has many advantages, so it is very popular with manufacturers. In particular, the outstanding advantages include the following:

• The image quality is higher, sharper, and cleaner because the rubber pad is evenly applied to the surface.
• It is applicable on many surfaces, even non-flat surfaces (such as wood, fabric, and rough leather).
• Offset printing sheets are easy to make.
• Printouts last longer.

>>> The power of the CMYK color system in offset printing
 

2. Steps of offset printing packaging

2.1 Design engraving

To get quality offset prints without errors, you must first create an engraving on a computer (or design a file).
 
The information should be presented on the design, both in content, form, and color, according to the actual needs of the business or the customer. When all is done, the process moves to the next step, called the film.  

2.2 Output film

After the design is completed, the printing technician will publish it to outfilm. For print versions with photos, the film will be out in four panels representing four layers of color C (Cyan), M (Magenta), Y (Yellow), and K (Black).

The CMYK color system is the basic color system that can mix to create all the other colors. The necessary colors are a combination of 3 or 4 colors with many different parameters to achieve many different color results. This process is called "four-film output"
 

2.3 Exposure to the zinc plate

After having 4 films, the printing technician will expose each sheet to the zinc plate, or to put it simply, take a picture of each film on each plate with a zinc exposure machine. This is the third step in offset printing.
   

2.4 Offset printing

During offset printing, the technician will print each color one by one; the arrangement of the order of each color will depend on the technician's experience.

Firstly, the printing technician will choose one of the 4 colors of zinc to install on the offset printer's batch. In the ink tray, the technician will also insert the silimar ink. For example, for C-colored zinc (Cyan), the technician also prints ink C and proceeds to print. The batch that goes back to the paper will smash the print element onto the print media.

When it’s all done, the technician will remove the zinc, clean the old ink, install new zinc, print the new colored paper, and continue the same process. The process proceeds sequentially until all 4 colors, the 4 colors that are printed on top of each other, produce the final print.

During the printing process, the technician will have to test the drafts to ensure the color is stable. In offset printing, the printer must deduct paper waste to ensure quality.

>>> The surprising benefits of the offset printing method
   

2.5 Post-print process

The final step to complete the offset printing is the post-printing processing. Typically, the most widely used post-printing processing processes is lamination and glossy lamination. In particular, matte lamination will create a smooth and soft surface. Glassy lamination will cover the surface of the ball completely up.

Matte lamination is the process of embellishing the product by applying a thin film layer to the surface of the leaflet after printing. This will help the printing look smooth and make the image more eye-catching. To ensure that the offset printing process does not occur errors, the printing technician must be really meticulous in every step to create quality prints.

>>> 8 Basic steps in the manufacturing process in Vietnam packaging company

Khang Thanh - The printing company in Vietnam

Khang Thanh is a leading Vietnamese printing company with a staff of qualified workers and cutting-edge technology. From design and prepress to printing and finishing, our staff is committed to completing every project to the greatest possible standard. With a commitment to quality, a focus on client satisfaction, and an emphasis on innovation, Khang Thanh is the Vietnamese printing service you can rely on for all your printing needs.

Contact us to support your brand with the right packaging