Gravure printing is mainly used in food packaging, leather, cigarette packaging, building household adornment material, the floor material, cloth in the field. Gravure printing ink high gloss, strong tinting, bright colours, stamping and dieyin performance is good, printing density, high contrast big, expand equilibrium, the network order plate printing resistance force, high printing speed of superiority.
The domestic numerous manufacturers use gravure plate making many ways, but with the printing plate technology in recent years to rapidly increase, digital plate making gradually dominate the market the mainstream.
Digital plate-making technology advantage
Digital plate-making is the original in was copied to the plate in the process of color information with digital signal in the form of transfer. Its main advantage is:
(1) to simplify the plate making process, make good graphic files through the computer control can get the printing plate;
(2) reduce the plate making direct costs, from the use of film cost;
(3) reduce the colour of reduction process signal loss, is more advantageous to the color management;
(4) the graphics solution in the roller continuous of seamless, for decoration, textile, and other fields practical strengthened;
(5) wide size change more freedom, the domestic made 2800 mm x 2000 mm wide plate of, did not need to be phototypesetter output film limit,
6 in the same the roller for implementation process provide many times the exact location, the same edition can have different line number, different Angle of the cable network.
According to the existing domestic actual situation, the number of gravure have three ways making:
(1) electronic carving machine way;
(2) the laser carved film and corrosion treatment after;
(3) of the alloy electroplating laser direct ablation plate making way.
A, electronic carving machine way
Electronic carving machine is application integration automation control of modern technology, with high quality stability of the precision machinery. Hell machine as an example to Germany, carving frequency 4000 Hz-8000 Hz string range: 40-140 line/cm, the original production after color separation, RIP through after BitTiff with 1-graphic format or notes to electricity transmission unit engraving machine workstation, through the digital signal driven diamond carving the needle on copper surface vibration plate cylinder, carved out of the pit. Diamond head carving a four LengZhui shape. The head of the carved out v have not only the pits shades changes, and the area size of variety, thus finished graphic halftone copy.
Electricity production data are all carved with digital form collection, can live in a subsequent one in use, and reliability. The original from being scanned into digital signals to let-off software to electricity transmission color separation and engraving machine or color play a prototype, so to standardization of production processes and standardization is very good, so as to ensure the quality of the printed matter more. And electricity use and TIFF carved workstation data transfer, after HelioLight group for the integration of the workstation edition convenient and set parameters configuration, carved by software to generate electricity carved curve, electric parameters and display record carved carving state until the CD save files (convenient used multiple times and revised).
Electricity carving process relatively mature, simple control, level reduction realistic. Defect is the amount of ink on the limited, ink layer for some rough print content covering power shortage; Due to mechanical graven nets acupuncture point and nets acupuncture point WangQiang division between, the nets acupuncture point of the line of inevitable serrated edge, the appearance of small text not clear when printing and easy to break or paste version. But the German haier recently introduced a new Xtreme sculpture technology, it can be as high as 400 line/cm number very fine under the cable to reproduce the most subtle parts, fine words don't rely on an independent selected number and carved record resolution, through optimizing the ink flow that outline is smooth and produce contour line. Can realize the conventional site, also can realize FM and network copying.
Electric equipment manufacturers of carving except the United States Ohio, Germany haier, Japan nets screen and Switzerland MDC products more mature outside, home also has developed a similar performance factory products.
Second, laser carved after film and corrosion process
Laser carved film and corrosion process is after the relay after a carved and advanced digital plate making way, it and the carved through the interface accept as color separation processed image file, will add nets after the graphic signal sent to the laser modulator, in the role of laser roller surface layer of protection and airless that bronze or iron bottom show, and by the time the corrosion of the different in the roller forming different sizes of the pits of outlets.
To the west German buss · Ohio SCHEPERS across, for example, use neodymium with yttrium aluminum garnet (Nd3 + : YAG) solid lasers, laser power is not higher than 50 W, through lens focused on 20 μ into the flare.
Laser to crush the roller surface black glue, scraps breathe in tube into the collection bags, reserved in black glue roller surface formation corrosion protection layer, and the last in the corrosion in the tanks of the liquid concentration control FeCL3 and spray time, in the copper layer or iron roller surface generating depth conformity and different sizes of the network.
Laser carved membrane technology overcome the electricity words and a fine line of engraving couldn FaXu, weakness, highlighted including ink volume is high, the color, the thick, clear, durable characteristic, with the traditional photographic gravure plate making and net increase compared with high precision, and can edit nets form, no juncture, etc. Apply to smoke version, security printing characters are so small but the requirement of high resolution screen, is widely used in monetary, securities, ticketing, high precision and high security printing tobacco packaging, in fine pressure lines roller and glue production process of roll more advantages.
Another is photosensitive agent laser mode and the purple and the part of laser light-sensitive layer exposure rinse again. Other technology with laser carved film basically the same way.