Metal effect ink technology analysis - wine label

At the end of the 1990s, the beer label passed through the stencil paper to the aluminum spray paper. The high-gloss, high-humidity, strong metal label allowed the high-end beer to be demonstrated. The high-end and ultra-high-end beer, which accounted for 15% of the total beer share, were all converted to aluminum spray. There was also a shortage of users for mid-range beer. The use of a spray-aluminum process wine label quickly accounted for 25% of the total paper label.

* Learned from cigarette marking technology*

The innovation of cigarette marking technology has promoted the development of more advanced wine labeling processes. In 2002, Wuhan Nanyang Government Printing Co., Ltd. tried a metallic effect ink to print a gold and silver cigarette pack for Hongjinlong Tobacco Group on a white card paper. The new ink printing technology began to tap the aluminized gold cardboard cheese. Compared with traditional aluminized gold cardboard, metal effect color printing Budweiser MEC label, in addition to slightly darker hue, brightness and gold card printing has the same effect, but can save a lot of costs. The metallic effect color printing prompted the company to invest RMB 50 million to install a Lemanic 820 eight-color machine a year after using the Bobst 620 gravure press to expand the production capacity of the product. In the same year, label printers such as Illochroma, Germany, H&N, and Topfer in Germany brought beer labels printed with metallic inks to China, and the Metallic Effect Color (MEC) allowed the beer industry to recognize that the new smoke label technology can be used for the wine labels.

*MEC principle*

MEC is printed on wet-strength printing paper with a whiteness of over 80% through the use of special PVD metal inks, resulting in a true strong gold or silver visual effect in photo or text. It is a new surface metal effect method after pure aluminum foil and aluminum spray paper. Its core technology is the development and application of metallic effect pigments and inks, which makes gravure prints with excellent aesthetics and applicability. Avery Dennison used vacuum metallization technology to make thin and flat metal light metal pigments. ECKART used it to process bright metallic effect color inks. Its metallic effect, stability, and functionality are not only suitable for printing in paper, but also for real glittering effects in surface printing. Measure brightness, hue, and saturation with a photometer, and the printing effect is very similar to that of aluminized paper. *The cost advantage of MEC* The main advantage of MEC in attracting breweries is cost. If the label design is appropriate and the gold-silver printing surface does not exceed 30%, the printed product will look closer to aluminized paper, but the cost can be reduced by 20% to 30%. The simple price calculation method is: the price of aluminum-plated paper is RMB 28,000 yuan, that of MEC wet-strength paper is RMB 14,000 yuan, and the cost of raw paper is reduced by 50%. Although the price of metal ink is very expensive, the amount of metal ink is lower than the balance point on the printing surface. The cost will surely drop.

After two years of marketing, MEC is no longer unfamiliar with the domestic printing industry. More and more brewers' packaging technicians are concerned about its development trends. The first batch of domestic and foreign brands such as Budweiser, Wusu, etc. Metal effect color label. MEC printing has its own subtleties. Domestic printing companies have tried to print MEC with offset printing presses, and the metal effect has been greatly reduced. The brewery will not be convinced that it can replace the high-grade beer aluminum plating standard at a lower cost. In fact, gravure printing is the solution. Road. * Gravure is better than Offset * Gravure printing is proved to be the best process for printing metallic inks. The gravure plate made of steel by laser engraving technology can enrich the transfer of graphic or field thickly. Metal ink is only applied in printing. When the amount is heavy, the bright effect can be better highlighted. The gravure coating amount is as high as 4 grams per square, and the offset is less than 2 grams. The metal vision needs the ink layer to reflect.

The domestic label printing market has a high market share of lithographic offset printing machines. It has a number of highly specialized label printers, such as Guangdong Wanchang, Hailibao, Wuhan Changyin, Nanjing Jinya, etc., with annual production capacity of several billions. Set above. There are two reasons why offset printing is popular in the label printing industry: First, offset printing has exquisite printing quality, which is in line with the appreciation of beer consumers' external decoration; Second, foreign offset printing presses once entered the domestic printing market at a low price, satisfying the printing industry. The orientation of printer prices also adapts to frequent reprints and short-run orders for breweries. This is an industry characteristic of the early economic backwardness and underdevelopment of the printing industry. As the domestic printing industry becomes bigger and stronger, it will be a matter of time before it becomes integrated into the international model. The integration of the beer industry and the unification of the brand image will lead the breweries to put forward requirements for printing and processing companies to be more conducive to gravure printing or flexo printing, such as batch, environmental protection and anti-counterfeiting. Beer labels are mostly used in Europe, America and Japan for gravure printing by gravure printing machines. The main reason is that wine labels are generally long-term large-volume prints with high efficiency, small color difference, and fast delivery.

In addition, the offset printing label is printed after the first embossing, and the MEC label is embossed after the gravure printing. This process adjustment helps the brewery to quickly and easily wash the label when it recycles the bottle, and ensures that the ink is solid during the alkaline wash. The ground is attached to the label paper, the label is removed from the bottle and the ink does not fall off, and the alkali liquor is not contaminated. The reason is that the offset label is printed on embossed paper and applied with light. The blockage of the pits by the ink layer is not conducive to the rapid infiltration of the alkali liquor, thereby prolonging the dissolution time of the glue and reducing the washing efficiency; at the same time, the off-line offset coating method does not provide a better result. With good alkali protection, the ink will be contaminated in the bottle washing tank after it is dissolved by the alkali, and the pure water bottle cannot be guaranteed. MEC is similar in application to hot stamping and aluminizing, and gravure on-line printing, coating, metalized material effect, aluminum foil effect, and bronzing effect are improvements to off-line production processes with high efficiency, low loss, and easy and flexible operation. Gravure can also reduce the amount of paper from the current 73 grams to 53 grams. The lightweight label on the one hand reduces the cost, on the other hand, it is flexible and is conducive to the downstream beer labeling process. * Performance characteristics of MEC label paper * MEC label uses high-strength wet coated paper with specially treated surface whiteness and smoothness. Under the light, the MEC mark is seen from the back, and since there is no coating of the sprayed aluminum layer, the metal color is clear and bright. The technical indexes for measuring the running ability of the label paper are: wet tensile strength, tearing degree, curling degree, reactivity with water, backside water absorption, time for washing labels, and alkali resistance.

The use of wet strength paper will reduce the strength of the paper under certain environmental conditions, such as the humidity in the brewer's packaging workshop, the high temperatures during filling and pasteurization, and the strong condensate caused by cold bottles. This can cause the label to be resistant to moisture and breakage. In the event of condensed water, the label can tip or peel off the bottle. The use of special high-strength wet papers (such as French Star Paper) for imported wine labels ensures that the labels are still very strong under extremely humid conditions and remain in good condition on the bottles. Since paper is a "live" material, it reacts to the labeling environment. In order to ensure good bids and reduce downtime or scrap labels, the flatness of the labels must be controlled. If the control of the flatness of the large sheet is not good at the time of offset printing, the label may curl, and the label may also curl after contacting the glue sheet. To control the degree of curl of the paper, low-resistance paper is recommended and gravure printing is used.

When labeling, too high or too low backside water absorbability will result in insufficient sizing or excessive amount of glue to cause labels to slip, fall off, or glue waste. By controlling the back-absorbency, the sizing performance and labeling conditions can be controlled.

Washing time is the time needed to wash the paper label from the bottle body. The length of time will affect the operating efficiency of alkali basins and the consumption of alkali. Usually, the brewery wants to wash the label for a maximum of 120 seconds. MEC labels can reduce the time required for washing the labels. Due to the alkaline water immersion during the labeling process, the label must remain intact and not decompose throughout the entire process. The MEC standard is to print the ink directly on white paper, so it has better anti-alkali ink retention, so that the standard off and the ink will not come off, keep the bottle cleaner clean.

In addition, the whiteness, wet opacity, glossiness, abrasion resistance, and printability of the paper being printed also affect the quality of the MEC label. The higher the whiteness of the printing paper, the higher the color contrast of the printing, and the better the effect of the MEC. Larger ambient humidity (such as water condensation) may reduce the paper's opacity, and the glue coating lines run through the entire label. When used on brown or green bottles, the label color will be darker, so use high-moisture opacity Paper. When MEC marked bottles are run on the conveyor line and packaging line, in order to avoid the label wear caused by friction between the bottles, MEC special paper adopts a special coating formula and adapts to the characteristics of gravure printing. Its good wear resistance. Sex may fully guarantee the quality of the finished product. Consumers often choose a beer from a large number of brands in just a few seconds, so the gloss of the wine label determines the consumer's choice to a certain extent. Aluminized labels have a natural surface gloss and white paper labels can achieve the same effect after being printed with MEC effect, so it is not worthwhile to select expensive aluminized paper for a metallic glossy surface of 30%. The use of high gloss paper can achieve the same effect.

Source: China Ink Web