Inklove UV Varnish Printing Ink

Definition

The so-called printing varnish is to print the varnish once or twice on the surface of the reproduction of the graphic printing with the solid printing plate or the graphic printing plate, so that the surface of the printed matter can obtain a bright VU film layer. Printing glazing can strengthen the ink Excellent light resistance, increase the ability of the ink layer to resist heat and moisture. Play the role of protecting imprinted beautification products instead of lamination.

Compared with laminating film, printing glazing is not only cheap, the process is simple, and it can be full plate glazing or partial glazing.

The Composition of UV Varnish

1. Oligomers

Oligomer is the most basic constituent substance in uv varnish, which belongs to a kind of film-forming substance, and its performance plays an important role in the curing process and the properties of the cured film.

2. Additives

The auxiliary agent can also be known from the surface meaning to improve the performance of the varnish. Commonly used additives in uv varnishes include stabilizers, leveling agents, defoamers, etc.

3. Active diluent

Reactive diluent, also known as cross-linking monomer, is a functional monomer that adjusts viscosity, curing speed and cured film performance in the role of varnish

Features of Paper Printing UV Varnish:

In foreign countries, the gloss processing of printed matter such as books, magazines, covers, and tape sleeves has been widely used, and the gloss processing of books and magazine covers generally adopts UV coating.

UV glazing is rising rapidly and has the potential to replace plastic coating and solvent-based glazing in many products, which mainly depends on its own following characteristics:

1) UV varnish contains almost no solvent, and the emission of organic volatiles is very small, so it reduces air pollution, improves the working environment, and reduces the risk of fire;

2) UV varnishes do not contain solvents, and do not require heat energy during curing. The energy consumption required for curing is only about 20% of that of infrared-curable inks and infrared-curable varnishes. In addition, this kind of varnish has strong affinity to ink and firm adhesion, and the curing speed can reach 100-300M/MIN under the irradiation of 80-120W/CM ultraviolet light;

3) The printed matter after UV glazing process is obviously brighter and brighter than other processing methods, and the cured coating is wear-resistant, more resistant to chemicals and chemicals, and has good stability. It can be scrubbed with water and ethanol ;

4) UV varnish has high active ingredients and less volatilization, so the dosage is saved. Generally, the amount of varnish coating on coated paper is only about 4g/m2, and the cost is about 60% of the coating cost;

5) It can avoid the defects that often occur in the plastic laminating process, such as edge warping, foaming, wrinkling and delamination, etc. UV glazing products do not stick, and can be stacked after curing, which is beneficial to post-processing operations such as binding;

6) Can be recycled. The problem of environmental pollution caused by the non-recyclable plastic compound paper base is solved.

Except for a small amount of UV varnishes in the domestic market are imported products from Europe and America, most of them are products produced in Taiwan. Ceres brand UV Varnish is also sold all over the world.

Composition And Type of UV Varnish

UV varnish is made of ultraviolet photosensitive resin, photoinitiator, active monomer and aid through scientific compound processing. The types of UV varnishes can be divided into UV inks and UV varnishes; UV varnishes for oil-based inks and UV varnishes for both, can also be divided into off-line UV varnishes according to the coating processing method, On-line UV varnish or both UV varnish.

Application of Paper Printing UV Varnish

UV varnish can be widely used in off-line coating of roll coater, gripper coater, gravure coater and flexo coater.

The high-efficiency roll coater for thick paper is composed of rolls rotating in the same direction, and can be divided into many models according to different combinations of rolls and centerline angles between rolls. The gripper type coater is suitable for paper with a specification of 80-120m; the gravure coater and flexographic coater are mainly for partial coating. The gravure coater coating can make the local image clear and the coating uniform. However, the amount of coating can only be adjusted by the amount of dilution. As long as the depth and shape of the gravure lines are not changed, the amount of coating cannot be increased or decreased. However, when the flexographic plate is coated, the edge of the image is prone to edge contours, which lack sharpness. However, the adjustment and revision of the coating amount are relatively easy.

After coating with any of the above-mentioned coating machines, a hot air oven or an infrared oven is generally used to volatilize the solvent, and then it is cured by ultraviolet rays. When paper is coated with UV varnish, it can be printed first, and the off-line method of coating varnish in post-processing can be adopted. The acceleration speed is generally 30-60m/min.