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Rotogravure (or gravure for short) is a type of intaglio printing process, which involves engraving the image onto an image carrier. In gravure printing, the image is engraved onto a cylinder because, like offset printing and flexography, it uses a rotary printing press.
Once a staple of newspaper photo features, the rotogravure process is still used for commercial printing of magazines, postcards, and corrugated (cardboard) and other product packaging.
In 1912 Messrs Bruckman in Munich produced proofs for Bavarian postage stamps which went into production in 1914. Also in 1912 newspaper supplements printed by reel-fed gravure were on sale in London and Berlin ( The Illustrated London News and Der Weltspiegel).
Irving Berlin's song "Easter Parade" specifically refers to this type of supplements in the lines "the photographers will snap us, and you'll find that you're in the rotogravure." And the song "Hooray for Hollywood" contains the line "…armed with photos from local rotos" referring to young actresses hoping to make it in the movie industry. In 1976, ex-Beatle Ringo Starr released an album titled Ringo's Rotogravure.
Gravure is one of several printing techniques being actively used in the field of printed electronics.
For indirect gravure processes, the engraved cylinder transfers ink in the desired areas to a transfer roller, and the transfer roller transfers it to the substrate.
| Conventional | uniform | variable |
| "Two positive" or "Lateral hard dot" | variable | variable |
| Direct transfer | variable | uniform |
Gravure cylinders are usually made of steel and plated with copper, though other materials, e.g. ceramics can also be used. The desired pattern is achieved by engraving with a laser or a diamond tool, or by chemical etching. If the cylinder is chemically etched, a resist (in the form of a negative image) is transferred to the cylinder before etching. The resist protects the non-image areas of the cylinder from the etchant. After etching, the resist is stripped off. The operation is analogous to the manufacture of printed circuit boards. Following engraving, the cylinder is proofed and tested, reworked if necessary, and then chrome plated.
Next, the substrate gets sandwiched between the impression roller and the gravure cylinder: this is where the ink gets transferred from the recessed cells to the web. The purpose of the impression roller is to apply force, ensuring that the entire substrate is brought into contact with the gravure cylinder, which in turn ensures even and maximum coverage of the ink. Once in contact with the substrate, the ink's surface tension pulls (part of) the ink out of the cell and transfers it to the substrate.
Then the inked substrate goes through a dryer because it must be completely dry before going through the next color unit and accepting another coat of ink. A rotogravure printing press has one printing unit for each color, typically CMYK or cyan, magenta, yellow and key (printing terminology for black), but the number of units varies depending on what colors are required to produce the final image.
Gravure is an industrial printing process capable of consistent high quality printing. Since the Gravure printing process requires the creation of one cylinder for each colour of the final image, it is expensive for short runs and best suited for high volume printing. Typical uses include long-run magazines in excess of 1 million copies, mail order catalogs, consumer packaging, Sunday newspaper ad inserts, wallpaper and laminates for furniture where quality and consistency are desired. Another application area of gravure printing is in the flexible-packaging sector. A wide range of substrates such as polyethylene, polypropylene, polyester, BOPP, etc. can be printed in the gravure press. Gravure printing is one of the common processes used in the converting industry.
Rotogravure presses for publication run at per second and more, with paper reel widths of over , enabling an eight-unit press to print about seven million four-color pages per hour.
The vast majority of gravure presses print on rolls (also known as webs) of paper or other substrates, rather than sheets. (Sheetfed gravure is a small, specialty market.) Rotary gravure presses are the fastest and widest presses in operation, printing everything from narrow labels to 12-foot-wide (3.66-meter-wide) rolls of vinyl flooring. For maximum efficiency, gravure presses operate at high speeds producing large diameter, wide rolls. These are then cut or slit down to the finished roll size on a slitting machine or slitter rewinder. Additional operations may be in line with a gravure press, such as facilities for magazine or brochure work.
Other appreciated features include:
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