Special Ink - Preservation Technique in Special Printing Field

The variety of special inks used in the field of special printing emerges in an endless stream, which not only makes the quality of printed products excellent, but also meets the needs of various special functions such as environmental protection and anti-counterfeiting, and expands the new direction and new ideas of printing development.

We will use special performance inks, special printing processes, and printing methods on special shapes or special materials collectively called special printing. In the rapid development of technology today. With the continuous improvement of printing quality, there is a higher demand for ink. The variety of special inks used in the field of special printing are endless. They not only make the quality of the prints good, but also meet the needs of various special functions such as environmental protection and anti-counterfeiting, and expand the new direction and new ideas of printing development, so that the printing can always Walking ahead of the trend of market consumption, and constantly maintaining the freshness and uniqueness of the development of printing itself.

Various "preservation" parties

There are a wide range of specialty inks, including UV inks, liquid crystal inks, fragrance inks, inkjet printing inks, and more. UV drying ink is abbreviated as uV ink. It will not dry on the ink roller during the printing process. Once printed on the surface of the substrate, it will be immediately cured by being irradiated with 300-400 nm UV light. It will take about 1 second to dry quickly. It is widely used in special varnish printing, metal hose printing, web form printing and cardboard box printing.

The liquid crystal ink is a compound having crystallinity added to the ink. Under the influence of weak current and temperature. The light and shade patterns and colors are displayed due to changes in the crystal lattice. Labels and packages printed with this ink can react with changes in temperature.

The difference between the fragrance ink and the common ink is the application of the fragrance. In order to maintain the stability and durability of the fragrance, the fragrance is made into a microcapsule with fragrance.

And add it directly to the ink. The ink can be applied to various printing methods.

The ink for inkjet printing is suitable for ink jet printing. The piezoelectric crystal is controlled by using computer graphics and information, so that the ink in the nozzle is ejected from the extremely fine nozzle under a certain pressure and is ejected onto the paper to form a dot matrix word. Or image.

Pearlescent ink can reproduce the pearl of nature

The luster and color of shells, butterflies, fish and metals. Pearlescent inks are low in price and excellent in resistance, and can prevent the copying of scanners, extensions, and color copiers from being applied to packaging, advertising albums, publications, and the like. Pearlescent printing can be carried out in offset printing, gravure printing, flexographic printing and screen printing.

Of course, in addition to the above-mentioned special special inks, there are electroluminescent inks used in certain specific fields, luminous inks that absorb, store, and emit light, and can be used to directly print offset lotteries or lottery tickets for various kinds of lottery scratch cards. Scratch card inks and inks used to make carbon paper, etc.

Unique market tricks

At present, special inks are widely used in printing applications. The printed products obtained have exquisite appearance and special effects and have expanded the new direction of printing development.

The printing principle of liquid crystal printing is to encapsulate the liquid crystal into a printing ink for printing. Liquid crystals have liquid flow due to its optical anisotropy

As well as being sensitive to changes in electric fields, magnetic fields, temperatures, stresses, and chemical environments, the color and transparency of these conditions will change as these conditions change. Therefore, if a liquid crystal component is added to the printing ink, the color development of the printed matter will change under certain conditions. For example, the outer surface of the lighter shell may be printed with a liquid crystal printing ink. The appearance may not be color, but once the flame is lighted, the heat is applied. With the effect, the pattern can be displayed immediately. The amount of liquid crystal blended in the ink is 40% of the total ink amount, and the ink film thickness is about 30 to 60 m. Printed products vary according to needs, with reversible reactions and irreversible reactions. The printing material for liquid crystal printing is preferably a paper with water absorption, and synthetic paper is also suitable. The printing method uses offset printing, gravure printing, screen printing or a combination of two printing methods.

When printing with a special liquid crystal ink, first use offset or gravure printing method to print the text and images, and then seal the ink encapsulated in the liquid crystal capsule, to pay attention to not damage the capsule, so most of the use of screen printing printing, must print the liquid crystal Part of the base is printed in black. In addition, because the liquid crystal ink is very afraid of moisture, after the printing is completed, a transparent polypropylene film is bonded on the surface with an adhesive for moisture protection.

Today, the use of liquid crystal printing has been widely used for printing display panels, toys, trademarks, simple body temperature belts, and health care appliances. The lifetime of liquid crystals other than those used in precision components and watches is generally about 1-2 years. The future research topic is how to prolong its life.

Ice printing is the use of printing processes on the substrate to print inks and other materials with the characteristics of ice flowers on it to form an ice flower effect. There are many types of ice prints, such as ice prints and metal ice paints.

The principle of printing ice flower is that when the surface of the substrate coating film is dry, especially by the influence of nitrogen dioxide, sulfur dioxide, carbon dioxide and other gases, the surface of the coating film will have a crystal grain. Crystal lines, crystal flowers, reticulate lines, and silk lines are all different manifestations of wrinkles and are a defect in coatings. However, if it can be controlled so that the proper formation of crystal lines in the coating can produce a crystal-clear, ice-like decorative effect. Ice print inks can generally be printed on special papers, paint cloths, mirrors, plastics, and metals. The ice lacquer process is not produced by the paint. It is generated by a special tin plating process. If the steel is specially tin plated, an ice-like tin plating layer is formed on the surface. The ice-like tin plating layer is covered with a layer of transparent varnish, so that the white ice flower is colored, the ice flower becomes more vivid, the decoration effect is more ideal, and the protection of the coating is also improved.

In order to meet the needs of the market, a daylight-type color-changing fluorescent anti-counterfeiting ink and a hand-temperature color-changing fluorescent security ink that can be used in tobacco and wine packaging are introduced to the market. The main features of the daylight-based color change and hand-temperature color-changing high-tech materials are: Has the controllability of raw materials; Second, the ink composition, production equipment, large investment, complex process, processing is difficult, most people are difficult to imitation; Third, with multiple anti-counterfeiting features, such as intuitive, daylight discoloration, hand temperature change, Concealed, fluorescent color; Fourth, the identification of convenience, the use of sunlight or hand heating can be identified, but also the common UV lamp detector.

This new type of anti-counterfeiting ink has its own unique technical characteristics. It adopts the principle of chemiluminescence to realize the uniqueness of fluorescence detection. According to the needs of customers, special patented fluorescent compounds can be used. Unique fingerprint recognition function, the only spectral characterization ink To protect the product from being counterfeited, the sun light is discolored, and the stability of the hand-warming color fluorescent material is high, which overcomes the disadvantages of the existing anti-counterfeit inks that are easy to be aged. The specificity of the product-specific anti-counterfeiting ink formulation locking is based on customer needs. The purpose of the product protection is to use a unique anti-counterfeiting ink product: A new type of anti-counterfeiting ink can directly print invisible or colored anti-counterfeiting images on coated paper, paperboard, plastic film and other materials for tobacco, wine and other packaging. Text.

Electronic ink printing enables digital offset printing, and the electronic ink contains charged liquid ink particles, which make it possible to electronically control the position of printed particles in digital printing. Electronic inks can achieve very small particles. Such small particles enable printing to achieve higher resolution and smoothness. Sharpened image edges form a very thin image layer. Digital ink offset technology using electronic ink has many advantages: Sharpness and sharpness of edges; Dots increase and color consistency: Image smoothness is good; spot color ink system can print six colors, Granville uses a primary transfer technology, color difference is small: instant drying; not under light fade.

Market Opportunity

At present, special inks have two major development trends: environmental protection and anti-counterfeiting. Eco-friendly inks, also known as green inks, are UV-curable inks and inks that are environmentally friendly alternatives to ink. The development of green ink is a prerequisite for achieving green environmental protection. To reduce environmental pollution, the development of green inks and the development of green environmental protection printing are gradually being recognized. Laws and regulations also encourage people to buy green inks. European environmental regulations have added provisions related to printing, which has a clear restriction on the emission of volatile organic compounds in the printing industry. This not only increases the content of waste disposal, but also provides a way to reduce the loss of ink. According to statistics, 60% of prints in the UK are printed with non-alcoholic or low-alcohol inks. In the United States, the Environmental Protection Administration (EPA) strongly opposes the use of solvent-based inks. Flexo Ink is currently the only non-toxic ink approved by the U.S. Food and Drug Association and is widely used for the packaging and printing of foods and pharmaceuticals. In countries such as Europe, America, and Japan, except for offset printing, ink painting is gradually replacing conventional solvent-based inks. For example, in the United States, 95% of flexographic printing products and 80% of gravure printing products use ink and ink printing.

The anti-counterfeiting development of ink is also a market trend. In the aspect of gravure printing inks, the goal is to increase production efficiency, reduce costs, enhance environmental protection, and improve the feel of gravure printing; in the light of variable light, the light change effect is improved, and the decrease The cost is the goal; in the area of ​​thermal inks, the performance of the heat-sensitive materials and the sensitivity of discoloration are targeted; in the aspect of ultraviolet laser fluorescence, the development system is targeted, that is, the detection instruments and related technologies are also developed when the ink is developed. Improve the anti-counterfeiting performance of its machine reading; In the infrared ink, with the development of a unique infrared transparent, infrared absorbing material as the goal.

Environmental ink can meet people's requirements for non-toxic and non-polluting printing. The market prospect of special ink is undoubtedly worth looking forward to. The future development of specialty inks will be to meet the needs of multi-color, high-speed quick-drying, non-pollution and low consumption, improve the quality of flexographic ink products, improve the adaptability to modern printing processes and product stability, and actively develop the current domestic still In the shortage and blank of a variety of water-based inks, anhydrous offset inks, food packaging inks and lightfast inks and other varieties, improve the application of special printing technology, and expand the printing development of new directions.

After several years of rapid development, China's special printing industry has formed a certain industrial scale, the relevant printing and processing technology has also become increasingly perfect, special printing has become an important part of printing. However, the domestic special printing market is still in the development stage, and the market is far from mature. Compared with the developed European and American countries, there is still a large gap between China's special printing industry in terms of market size, product level, variety specifications, and consumption levels. , to be further improved and expanded.

Reprinted from: China Printing Author: Wangshang Wei Li Fenghua