Offset Printing

Color Separation

Color separation is performed for orders that have completed the pre-design process and received customer approval to proceed to the offset printing stage.

Color separation is the process of separating the colors that make up the original design into the CMYK primary colors used in printing. These primary colors are cyan, magenta, yellow, and black. Each of these separations is exposed onto a separate plate. The exposed plates are then printed on top of each other on the same carrier to produce the print.

Today, after color separation, files are typically transferred directly to CTP (computer-to-plate) devices, which are products of advanced technology. However, in addition to trichromatic (CMYK-printed) jobs, there may be a spot (extra) color on our work that cannot be obtained from trichromatic colors or that requires emphasis on color intensity. This color must also be printed by being transferred to film and plates, just like CMYK colors. At this stage, depending on the nature of our work, we need to perform certain operations using vector drawing programs or image processing programs to ensure that the spot (extra) color can also be printed, and save it in the correct format.

The lightness and darkness of colors are created based on the size of the halftone dots, which have specific angles. The most dominant color forms a 45-degree angle (this is usually black). The least dominant color forms a 0-degree angle (this is usually yellow). Magenta and cyan usually form angles of 15 or 75 degrees. The reason these dots form angles in this way is to create different tones without overlapping. Our eyes perceive the dots side by side together. If color separation is not performed at the specified angles, a pattern problem called “mottling” occurs. Three important terms used in color separation: Tram: Points that create transitions (shades). (Number of points per 1 cm). Tire: Solid colors without transition tones. Refers to film made without using dots. Lup: A special magnifying glass used in color separation.

ATEŞLER AMBALAJ performs color separation directly on the CTP plate using its own equipment. The KODAK CTP Plate Machine XPOSE! Thermal Model and the KODAK CTP Processing Machine are the two machines we use for this purpose.

CTP Molding

In the final stage of offset printing preparation, printing plates must be made according to color separation studies. Plates are made of metal (aluminum) and are an important material that affects the overall quality of color printing. In orders with color separation according to the CMYK primary colors, each color separation is exposed onto a different plate. The exposed plates are then printed on top of each other on the same carrier to produce the print.

These processes are carried out using CTP (computer-to-plate) devices, which are products of advanced technology. The KODAK Tredsetter Platesetter CTP machine and the KODAK CTP Bath Machine are the two machines we use for this purpose. Under the supervision of our experienced plate technicians, the Computer-to-plate (CTP) system, which means preparing plates directly from the computer to the plate, produces plates with increased sharpness and detail depth compared to the old film transfer systems, without any loss or error. The printed plates are produced in a shorter time and are more durable. Thanks to the digital records of plates that need to be replaced after a certain number of prints, the process of repeating the production cycle is significantly reduced.

Cardboard Cutting

Bobbin sizing is the process of cutting cardboard material to be used in offset printing from large rolls into rectangular or square shapes suitable for the printing mold. This process is very important because it determines the waste rate and has a direct impact on costs, so it must be planned correctly. Cardboard sheets cut quickly on automatic machines are stacked on pallets and made ready for use in the offset printing machine. Our factory maintains a stock of cardboard rolls in various widths for sizing operations. The cardboard size that will result in the least waste for printing one or more box designs on each mold is determined in advance by planning. If the correct width roll is not available, cutting is done according to the closest dimensions. Using different dimensions, however, will significantly increase waste rates. Proper stock management is therefore of great importance.

Print Approval

Orders that are ready for offset printing are scheduled for production and placed in a queue. For jobs that are being printed for the first time, designs that have been modified, and ongoing jobs for new customers, Ateşler Ambalaj schedules appointments with our customers and invites them to approve the print. Even if we have already received general approval for orders, a second approval process with our customers during printing is always advantageous, especially for jobs where print colors are of primary importance. This way, our customers can inspect our production line at our factory and evaluate our quality, as well as perform a valuable check to ensure that their orders are produced without errors.

In cases where customers cannot visit, the printing approval process is carried out meticulously by our experts, taking into account the color specifications and important notes provided by our customers, based on the available sample or chromalin output. The approved work is then quickly moved into production and the printing is completed.

Offset Printing

Offset printing is also known as lithographic printing. It is based on the principle that water and oil do not mix. The blank areas of the printing plate that do not contain images absorb water. The plate is kept moist so that the printing ink adheres only to the areas with the image. With each rotation, the ink is transferred to the offset cylinder with a rubber surface and then transferred to the cardboard. The flexible surface of the offset cylinder protects the delicate surfaces of the plates and ensures that even specially textured papers absorb the ink well.

CTP plates are connected to the machine, and inks composed of CMYK and extra colors are added to the system, which has been thoroughly cleaned beforehand. Pre-cut cardboard sheets are also placed in the machine's automatic feeding section. A test print is performed at low speed on the machine ready for printing, and once the job reaches the desired values, samples are taken from the test print, and printing approval is granted. In the subsequent process, depending on the cardboard used and the printing details of the job, our COMORI LITRONE 50 machine prints up to 7,000 cardboard sheets per hour on cardboard sheets with a thickness of 0.1mm-1.2mm and dimensions of up to 1050mm-1315mm in Format 6B.

One of the two important points is that when printing on cardboard boxes, the compatibility of the first samples printed on the offset machine with the knife mark must not be overlooked. The offset print sample is compared with the transparent control output printed on the special film of the pre-prepared knife mark. If there is an error, production is stopped, and the issue must be resolved.

The other point is that our craftsmen's efforts and experience ensure consistent quality during printing through continuous monitoring. With the special integration and control systems in our machines, these processes have become much easier to track.