Waterborne Printing Varnish Introduction

Environmental protection is not just an economic issue but a big issue that affects the entire human existence. Printed products are one of the most widely penetrated products of human life, and are naturally of concern to society and people. In terms of packaging, printing, commercial printing, etc., in recent years, there have been increasing requirements and restrictions on hygiene, environmental protection, and labor protection. In particular, the requirements for food packaging and printing have become more stringent. Only in this way can international standards be met. Claim. Under this general trend, it is imperative to strive to develop and apply pollution-free, pollution-free “green” materials. Water-soluble coating oil is a new kind of printing and glazing material that has been researched and developed by developed countries in recent years and is increasingly valued by people in the printing industry. It is a method for obtaining a bright film layer on the surface of a printed matter by printing the surface of a replica of the graphic printing process with a solid plate or a graphic plate and then printing the oil once or twice with a printing machine.

Waterborne printing varnishes are made from synthetic resins, related additives and water after being processed by scientific processes. It is non-toxic, non-irritating, non-organic volatile, low cost, wide source of materials, etc. It is unmatched by other solvent-based coatings. Waterborne varnish can eliminate the harm to the human body and the pollution brought to the environment during operation. It has been paid more and more attention by food, medicine and tobacco printing enterprises. What are the advantages of waterborne varnish in comparison with solvent-based varnish in addition to its environmental advantages? Based on our experience in practical applications, we can summarize the following points:

1 High transparency, good gloss, no influence on the color of the printed matter, and the brightness of the printed matter. Under long-term strong sunlight, the waterborne varnish is not easy to yellow.

2 Strong abrasion resistance, scratch resistance, surface wear resistance, no discoloration, water repellency, oil repellent, deeply welcomed and trusted by users, especially cigarette packs, at speeds up to 300-500 bags/minute During operation, the smoke mark must bear a large mechanical load. For this purpose, the printed product not only needs to be glazed, but also has a strong abrasion resistance. The water-based coating oil can not only fully meet this requirement, but also whether it is gravure or offset printing. No phenomenon of cigarette packs disappeared.

3 Conjunctiva fast, fast drying, waterborne varnish applied on Heidelberg CD five-color stencil offset printing machine, printing speed 13,000 sheets/hour, infrared drying power 5.4KW×5 pieces×2 sets, completely dry at a temperature of 65°C , achieved a satisfactory application effect.

4 Use, transportation, storage and safety, water-based coating oil is conducive to safe production and improve the working conditions of employees. Due to the fact that solvent-based coatings are dangerous goods, transportation, storage, and use are very inconvenient. Water-based coatings use water as a solvent without any danger and are safe and reliable to use. After the light is finished, the printing roller, the machine and the liquid tank can be directly rinsed with water to keep the machine and workshop site clean and clean without polluting the environment.

5 non-toxic and odorless, waterborne varnish using water as a solvent, only a small amount of volatile edible ethanol as an auxiliary solvent, it is particularly suitable for use in food, medicine, tobacco packaging. Tobacco is a very easy-to-smell plant, and the use of water-based polish can completely eliminate the possibility of odor.

6 high temperature resistance, heat sealing performance, cigarette packs are widely used as a package of PP film. Waterborne coating oils have good heat-sealing properties, and even with Celluloid, good heat-sealing results can be obtained.

7 Good flatness and strong anti-rolling force. One of the most difficult problems in gravure printing is the continuous drying of the printed material through several color groups. The moisture content of the paper is extremely low, and it is particularly prone to curling, making it unusable. After applying waterborne varnish to soft packaging, the product is cut into large sheets, then hot cut, and still maintains good flatness and anti-rolling properties. This is to change the gravure from offset printing, especially the need for hot stamping to change the gravure Provides a new road.

8 The price is reasonable.

In addition to the above advantages, water-based coating oils are also very convenient to use. In particular, the conjunctiva drying process is more advantageous than solvent-based or oil-based coating oils. In general, the resin starts to polymerize at room temperature from +5°C to +10°C, and when the coating agent also contains 20 to 30% moisture, the coating process is basically completed. It is not difficult to see from the process of conjunctiva of water-based coating oil that water-based coating does not require too much temperature, and the use of water-based coating oil on the gravure printing machine is more convenient than that of general solvent-based coating oil. It is mainly to control the viscosity of the coating oil, the depth of the anilox roller and the temperature of the oven, and the coating oil can be instantly hot-pressed and die-cut. (bush)

Reprinted from: Bo Wang Technology