Gravure is small cells recessed into a cylinder that hold ink. The cylinder is washed with ink; a doctor blade removes the excess, leaving ink only in the cells. The ink is transferred to a substrate (paper, plastic, film, and more) using a rotary press.
Rotogravure, or gravure, is an old process. Building on earlier printing methods, modern gravure began in the late 19th century and became widespread in the early 20th century. The popularity of the Sunday rotogravure section, which was filled with printed photographs, increased the use of gravure.
Today gravure printing is widely used in:
1.Publication printing (magazines, newspapers, catalogs), where long runs at high speed are common. Gravure's remarkable density range makes it the best choice for fine art and photography.
2.Packaging printing, where printing on a variety of substrates is needed. Long runs are also common.Gravure is also used to print laminates, gift wrap, wallpaper, postage stamps, and the text on candies and pills, among other things
Cylinders for gravure have been made in several ways. First came chemical etch, followed by electro-mechanical (diamond cutting) and then laser etching. The latter two use digital images and controls.
Gravure cylinders are extremely long-lasting. They are made of steel, coated in copper for engraving, then finished with chrome. When the cylinder is no longer needed, the chrome and copper can be removed and the steel base reused.
Because of the stable steel bases, gravure cylinders can be quite large. Some publication presses run 3 meter (9.84 feet)wide cylinders. Cylinders can also be extremely small: 16 inches wide or even less. Cylinder diameters can also vary from very small (2.5inches or 64 mm) to very large (40 inches or 1,016 mm).
We offer all of the technologies for imaging gravure cylinders found in the market and work exclusively here with machines produced by market-leading manufacturers. We adjust the size, form and depth of the cells individually to the printer’s printing materials and inks, as the optimum transfer of printing inks to the printing material succeeds or fails with correct cell geometry. We guarantee substantial flexibility and punctual delivery deadlines through the standardization of the gravure process inside our entire network.
Electromechanical engraving as well as high-resolution ‘Xtreme Engraving’ and ‘Transcribe’ process impress through their high quality of detail reproduction and counter sharpness. Our gravure machines can engrave up to 12,000 cells per second in the copper layer of the gravure cylinder.
2.Direct laser engraving
The high quality of the Daetwyler Direct Laser Systems (DLS) is demonstrated in the image area through high-resolution reproduction and outline-free vignettes, and in line elements through sharp-edged text reproduction and excellent evenness of the ink. The relatively strong laser engraves directly in the cylinder’s zinc surface. At 70,000 cells per second, the DLS process is around ten times faster than electromechanical engraving. In addition, both the cell size and shape can vary.
The Cellaxy laser is also a direct laser, although it engraves directly in the gravure cylinder’s copper surface. The gravure is distinguished by a very high resolution and edge definition. With this highly innovative gravure process, we have the possibility of generating individual halftone dots and of producing high-quality line-/ 3D-embossed engraving. In addition to all of the applications for packaging and decor printing and for high-quality embossing forms, this engraving process is predestined for security/security paper printing, for highly-detailed elements in packaging printing (e.g. EAN-Codes/2D-Matrix) as well as gravure elements in RFID printing forms.
4.Laser etching (digitals laser)
As in the past we use the traditional, but high-quality laser etching process to produce gravure cylinders and embossing rollers. This is because the wide spectrum of outlines and cell geometries also ensures clearly sharp fonts and edges in complex designs. This technology is ideal for the packaging sector and security printing in particular.
We also use think laser technology for the highest detail-resolution and halftone layout demands. For example, the finest dot elements can be organized precisely for security printing using this process.
Gravure Cylinder Use for :
Each printing process has its strengths. Gravure has many:
"Gravure has fewer variables to control than other printing processes, ensuring more consistent print quality throughout a run." ("Gravure Process and Technology" 5)
Gravure provides "consistent color throughout a press run, even when that run consists of several million copies." ("Gravure Process and Technology" 7).
Gravure is a direct printing process: the image on the cylinder is printed directly to the substrate. This results in better ink laydown and thus a more faithful image rendering.
Image data wrapped around the cylinder can be continuous, so no plate seam shows, such as in wall paper or gift wrap.
Gravure printing routinely uses a wide variety of substrates:
@Publication printing: Very thin paper, coated paper
@Packaging printing: Cardboard, plastic film, aluminum foil, laminates, vinyl, non-porous materials.
The depth and size of engraved cells determines the amount of ink that can be put on the substrate. Gravure printing can lay down more ink than other processes.
Gravure presses run at high production speeds: 3000-3300 feet per minute.
Cylinders are extremely durable. Print runs of 2 million to 3 million from one cylinder set are common.
The diamond cutting tool (the engrave head) can cut at speeds of up to 10,000 cells per second. Special applications use cutting speeds much lower, such as 2000 cps or even lower.