What is the gravure printing technique?
Gravure printing, also known as concave printing, is a printing technique that uses a copper-plated printing roller about 100 microns thick, the printed elements (images, writing) are deeply etched and located under the surface of the printing roller. The non-printing element is located on the surface of the paint roller, and most gravure printing is printed mainly in rolls.
Gravure printing technology is now considered a modern printing method applied to packaging printing technologies, plastic packaging printing… Gravure printers can print on all film materials, composite coatings, providing customers with high-quality products.
Structure of printing mold in gravure printer
Usually, this printing mold will be in the form of a metal shaft, made of steel and the surface is usually plated with a thin layer of copper and the elements to be printed will be engraved on this copper surface by acid or by an engraving machine.
Finally, the surface of the copper tire will be plated with a thin layer of chromium to protect it, so this type of printing is also known as the chrome on method.
This printing method is very convenient if you want to restore or reprint when needed, just keep it well and the accuracy of the reprints is also very high.
It is now possible to fabricate gravure printing molds by photochemical or electronic etching methods. Photochemical methods are based on photographic processes, physicochemical processes, mechanical processes, and electrolysis.
Gravure printing is operated on the principle of concave printing, the printing elements are engraved concave into the metal surface. When the ink is fed onto the surface of the print plate and then spills into the indentations of the printing element, a device called a wiper will then remove the excess ink from the surface of the print plate. That time only ink remains in the recesses of the printed element. Finally, the printing pressure will cause the ink in the depressions to transfer to the surface of the material, each finished printing unit has a drying unit because the gravure ink has a low viscosity of only about 0.1 Pa.s to help the ink faster dry and better print quality.
Gravure printing is applied in the packaging printing industry such as printing laminated film packaging, plastic bags… Gravure printing can be applied on many different materials such as paper, flexible plastic film, thin metal, PE, OPP, MPET, PET… with many types of packaging that require us to print and then put them together to create into the finished product. This printing technique is called gravure printing.
Gravure printing, although quite new, has many outstanding advantages compared to some traditional printing techniques such as screen printing. The first thing to mention is the print quality, the ink is even and has a deep surface coverage. Very high accuracy compared to traditional printing.
The image is highly realistic and color fastness is high. The durability of the printing shaft is larger, so it can print and reprint more times, the printing speed is also very high, reaching over 200m per minute for modern gravure printers. Especially, it can print in large quantities, so the price is cheap and economical.
However, the disadvantage of this technology is the high cost of the print axis and the large print volume of 500,000 rpm or more.
Application of gravure printing in the production of plastic packaging
Gravure printing is mainly applied in the plastic film packaging industry. All kinds of product and food packaging such as washing powder, dishwashing liquid, confectionery, coffee … are printed by this printing technique.
Gravure printing will help the packaging produce large quantities, sharper, and more eye-catching images. Currently, more and more plastic packaging companies have applied gravure printing technology in production to bring the most convenience to customers.
Amiba packaging is also one of the leading units in applying this printing technology to its products. Amiba uses a 9-color printer (can print 2 colors on the matt surface) and a 10-color printer with a speed of 250m/min with B&R Austria’s color overlay system.
Gravure printing process
Step 1: Design printing samples on the computer in 3-dimensional space, then based on the packaging samples to create eye-catching and impressive images/words that are suitable for the product.
Step 2: Produce prints made from gravure printed’s images or elements.
Step 3: Arrange the printing mold so that it is optimal to save production costs, reduce printing costs to the lowest level.
Step 4: Operate and print the images of the bag based on the principle of gravure printing. Note that it is recommended to print sample products first, adjust and evaluate whether they have met the requirements before continuing to print in bulk.
Step 5: Make a mold to shape the packaging by attaching the cutters and grooving knives on a wooden board to create a mold, cut and groove the printed sheet, or cut into individual labels specials for brands.
Step 6: Process the printed sheet into a product, glue the vertical edge of the bag, remove the excess or error to form a complete package.
Amiba Vietnam Co., Ltd specializes in supplying and manufacturing all kinds of plastic packaging and composite film packaging. With a system of modern production workshops and leading technology in Vietnam and a team of skilled staff, we are ready to meet all of our customers’ needs for plastic packaging.
Please call now +84 796 290 555 to have a team of technicians support to answer as well as provide the most optimal solutions in accordance with the budget of the current business.
Address: No.8 VSIP II-A Street 16, Vietnam – Singapore Industrial Park II-A, Vinh Tan Ward, Tan Uyen Town, Binh Duong Province
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Tel: +84 796 290 555