In mã vạch sử dụng công nghệ in flexo

Currently flexo printing technology is being used popularly in the printing field. The question when many customers need to buy commercial flexo printers will have the question of where to find the main suppliers of high quality printers? Which type of flexo printer to choose modern quality?

Which flexo printers want to print barcode labels? Operation method for printing complete label stamps. Let's find out the articles below.

Usually flexo printers have 02 types, one is printing in the form of a stamp, the second type is printing in the form of a roller. The die form gives the image quality on the product is relatively average, the sharpness is not high.

For roller printing, it is relatively more complicated, high cost because it produces sharper, more beautiful prints.
 

Flexo printing molds belong to high printing group, they have printing elements on the same plane and higher than non-printing elements. The non-printing element (white element) is lower, the lower level depends on the printing and making the mold. The image on the mold is in reverse of the mirror to the printed sheet if printed directly and in the same direction as the printed sheet if printed indirectly. Printing molds are made on soft materials such as rubber or soft polymer compounds in the form of loose pieces or whole sheets. The thickness of the plate is from 0.8 to 8 mm, the hardness of the plate is from 40 to 60 shore. The height of the printed element relative to the non-printing element is 10 to 20 in the text area, in the background, and the stripe is equal to 20 thickness of the plate.

The flexo printing mold is made of photopolymer plastic. The printing mold can be fabricated by photochemical method, CTP or laser etching, and then attached to the printing roller using double-sided tape or a magnetic field. Choosing the printing mold includes thickness, hardness, number of layers, depending on the printing material such as paper, carton or film, we decide the appropriate printing material.
 

Print mold on Flexo machine, Polymer material.

Normally, printing labels on Flexo machines must use paper in rolls or roll paper, it is different from Offset printing. You can choose from plain paper such as AW0331, AW0339, MW0066, MW003 ... These are common types of paper that can be torn by hand, more advanced, PVC plastic decal paper, or transparent decal paper ....
 

Paper materials for printing labels, stickers, labels.

Label printing ink on Flexo machine is also different from ink on barcode machine, it must use water-based ink, barcode printer uses powder ink to cover PE film then roll the roll.

Depending on the purpose of use such as packaging, labeling, printer type, ink supply system, drying system ... or the standards of the inspection system that the different ink composition and basically Flexo ink divides do 3 types:

- Ink is based on organic solvents, the ink content includes:

+ Solvent: 60-80%: ethanol; n-propanol; n-propylaxetate; nepan ...

+ Plastic (soluble in organic solvents): 13%: nitrocellulose, polyamide, hard plastic, acrylic, colophane, shellac ...

+ Pigment: 8-12%, Additives: 2-5%: plasticizer, silicone ... The mechanism is dry by evaporation and usually printed on paper or film, the composition for each material used is different.

Label printing ink, UV ink.

- The solvent-based ink is H2O, the composition ratio is the same, the water can be mixed with organic solvents, dissolved resin or dispersed in the solvent, Pigment has a greater color density than in organic solvent ink. , dry mechanism: 70% absorbent, 30% evaporation

- UV ink has the following components:

+ Plastics: are short-chain polymers, monomers: acrylate, epoxy .. containing C-O-C bonds

+ Initiating activator: 10-15% have the effect of creating polymerization reaction under the effect of UV rays.

+ Pigment: 14-20%

+ Additives: 2-5%, the mechanism is dry by UV light, so there must be a UV lamp placed after each printing unit, the printing ink uses 4 CMYK primary colors, if additional colors are printed.

It is the final stage to produce the product, the knife is used for the product to have a beautiful shape, according to the requirements of the customer. Usually there are two types of knife in Vietnam imported from China and Japan

The knife picks up the stamp, depending on the shape of the stamp, but the bend, straight, folding, and segment.

The Flexo printing technique gives not as high a print quality as other technologies if printing in image form. Usually flexo printing often uses color phase (solid color) with anilox axis to guide the ink, so the advantage is that the product quality when printed is uniform and has a dark color because using Tram 150 DPI. Flexo printing technology is being widely used and has great potential for development thanks to the advantage of meeting large production progress, printing on roll materials for automatic gluing machines.

Labels of finished products

Finished product barcode

Especially, flexo technology has an automatic closing system right after the printing process. If the printing materials are decal types, the excess parts of the product are also peeled off the adhesive base. The flexographic printing method is an appropriate choice to print labels, stickers, stamps, labels, labels, packages, cartons, and print on many special materials such as fabric, cardboard or printing on polymer films….