Metal foil was first used as a special beer bottle seal decoration and security change about 100 years ago, today's beer label packaging called the material of the material is actually a high content of pure aluminum, traditionally foiling (Foil) metal was once lead Or tin-plated lead, which is why the domestic aluminum foil label is still called the tin foil label. The advantage of aluminum foil is that it is easy to process, has good printability and fit properties, and does not affect the printing and labeling due to silk flow compared with paper labels.
After processing, the surface of aluminum foil has been treated with glazing, smooth, clean and bright. It is suitable for gravure gravure printing or flexo printing. It is not limited by the color, pattern and design. It can also print temperature-sensitive special inks to warn consumers. Good drinking temperature; or increase the function of unscrew the cover, and pinch the hole line along the bottom of the bottle. When labeling, the labeling glue cannot be pasted under the pinhole line. If the top label is straight, the pinhole tears accurately to indicate the bottle. The cover has been opened.
Beer aluminum foil top label, also known as cap label, with original natural metal texture, brightness, eye-catching higher than any other substrate, like the crown of the exquisite jewelry, and abdomen, back standard seamless, to create the perfect brand beer . Many European and American high-end beers use aluminum foil caps, domestic 60% for 640ml, 630ml, and 500ml bottled aluminum foil. With the national total beer consumption and high-end beer growth at 15% and 10% respectively, it is expected that the next few years Aluminum foil prices are maintained at around 20%.
Aluminum foil application performance
The original aluminum foil used in the printing factory is made of four standard aluminum ingot melting, hot-casting, rough-pressing, and fine-pressing processes with a purity of 99.5%. The thickness of the domestic beer sealing standard is approximately 0.011mm, and the German beer standard is double. Zero, that is, 0.009mm. After the aluminum foil is formed, the surface layer lubricating oil is removed from the aluminum foil by means of evaporation. The grease is applied to prevent the foil from sticking during the roll pressing. The surface of the finished foil cannot retain any oil traces, otherwise the adhesion of the printing ink will be affected. A corona treatment device is generally installed on the printer to increase the dyne value of the printing surface and increase the ink/glazing fastness.
After printing, the foil aluminum foil is embossed/punched, cross-cut, flattened, die-cut, or die-cut in several steps behind the packaging plant to produce a customer-required standard shape. These mechanical processes affect the mechanical properties and processing performance of aluminum foil materials in different degrees. The optimization of wiring can reduce the damage to the tensile strength (Mpa) and elongation (%) of the aluminum foil, and finally ensure the labeling adaptability of the brewery.
The label factory adopts domestically produced downstream equipment, which is basically based on stand-alone operations. It consists of embossing boring machine, cross-cutting machine, flattening machine, die-cutting machine (vertical mark) and punching machine (special-shaped mark). Germany, Italy equipment only two production lines, embossing / puncture / cross / flattened, die-cutting machine (vertical standard) and slanting (profiled) on the same machine operations. On the one hand, the embossing functions as a label's aesthetics, flower-shaped worm-like, cup-shaped, etc., diagonal bar; on the other hand, helps the tightness of the aluminum foil stack, reasonable embossing depth and the process sequence of the first back hole can be After the aluminum foil is transectionally cut, it is closely attached like “butterâ€. There is no space formed between the single sheets of aluminum foil, so that the die/punching knife is sharp and straight, thick and straight. The pinhole size, density, and evenness affect the tensile strength and the distribution of the labeling glue, but mainly affect the drying time of the labeling glue. The brewery requires that the moisture released from the label through the pinhole is the fast drying period after the labeling. 4 days.
If the brewery is filled with recycled bottles, the efficiency of the bottle washer must be considered. Aluminum foil chemical properties are reflected here. The commonly used bottle cleaning agent is a 1% sodium hydroxide solution supplemented with various additives. It can completely dissolve the aluminum, metal salt, copper, zinc and other metal materials from the glass bottle decoration. The pinhole should ensure that the lye is fast in minutes. Penetrate the inner layer of the label and allow it to peel off from the bottle and melt within minutes. The use of high-quality ink and water-based varnish can reduce the contamination of cleaning lye, ensure that there is no scaling in alkali tanks, no toxic waste water, and the minimum amount of chemical additives. In addition to the regular slag removal, the bottle washer does not need to change the lye frequently, and the brewer usually exchanges liquid once or twice a year.
Aluminum foil labeling properties
Burst pressure is the main strength indicator of aluminum foil caps, high-quality labels can adapt to the labeling speed of 100,000 bottles per hour, imported Pechiney non-pinhole aluminum foil burst pressure is greater than 55kPa, domestic high-quality aluminum foil such as Haashun, Bohai, Northwest Aluminum is not lower than 42kPa; imported aluminum foil arch height is greater than 4mm, domestic aluminum foil is slightly lower than 4mm; high-density micro pinhole aperture is 7um × 8um, to facilitate the rapid solidification of glue, so that aluminum foil better positioning on the bottle; embossed structure using paper roller or Steel roller, moderate depth of embossing, can not affect the strength of aluminum foil.
The finished aluminum foil has 15 conventional shapes that are basically changed in size from the square, T, and waist shapes. The glass bottle mouth is an uneven spot, after the sealing, the crown cap skirt forms an irregular angular corner, and the special bottle mouth and the cap ring increase the difficulty of cap fitting.
The labelling effect of bottled beer is determined by a number of factors, including labeling technology (labelling machines), operators, bottles, adhesives, and label quality. The labeling process is that the rubber roller and the scraper cooperate to form a film of a certain thickness on the rubber roller, and when the target plate passes the rubber roller, the adhesive is applied and a tag is stuck in a rolling manner when the front end of the standard box is rotated; The target plate continues to move, and the uncovered label of the exposing barrel is peeled off by gripping the side edge of the label. When the labelling cylinder is turned to the side of the turntable, the aluminum foil is attached to the bottle via the labeling sponge ( The body mark is affixed at the same time); the labelled bottle will rotate with the tray at the same time as the bottle turntable advances, and the label will be brushed flat when passing through the brush mark group; finally it will go to the pressure mark star wheel. The top part of the lid is flattened. The aluminum foil is placed on the labeling machine in contact with the labeling unit such as the standard box, the target board, the target barrel, the rubber board, the standard brush, and the standard pressure. After being subjected to multiple movements and pressures, the aluminum foil is sealed on the bottle mouth. Aluminium foil labeling requires correct labeling, leveling, alignment of the body mark, no scratches, wrinkles or breakage, and no glue marks.
More and more high-speed labeling machines are used in domestic breweries, and aluminum foil labels should be able to meet labeling speeds of at least 40,000 bottles per hour. As the target plate wears at a high speed and in a large amount of use, defects such as unmarked marks or unequal adhesives are caused; uneven thickness of the target plate may cause poor adhesion between the tag and the bottle, resulting in wrinkles or Foaming conditions. The beer packaging workshop needs to regularly maintain and replace the target. The solid caking on the surface of the sizing brush can also make the sizing surface uneven. You need to clean the squeegee brush every day and check or replace it regularly.
Al foil labeling efficiency and label dimensions, punching quality and embossing depth are closely related. When the dimensional deviation is too large, the mechanized labeling cannot be realized at all. The label either sticks in the standard box or falls out of the front of the standard box. The poor punching quality may cause the label stack to stick together, resulting in difficulty in obtaining the label or failure. Inspection shows that the label surface is smooth and tidy. Improper embossing will reduce the strength of aluminum foil. Generally, the brewery is not equipped with an emboss depth detector. The theoretical formula is: depth = (M × 10000) / (F × 2.7), M represents the weight of the aluminum foil, and F represents the area of ​​the sample square cm.
Aluminum foil for packaging has a promising market
With the rapid development of China's national economy and aluminum processing industry, packaging aluminum foil has become one of the most important consumption growth points in the aluminum foil market. At present, China consumes 163,300 tons of aluminum foil each year, and it has become the second largest consumer of aluminum foil in the world after the United States. However, there is still a large gap between the per capita share and developed countries, especially the amount of aluminum foil used for packaging. Limited, with a broad space for development.
Air-conditioning foil is the largest consumer product in China's aluminum foil market; the second is tobacco foil. As the world's largest cigarette producer and consumer, China's annual consumption of cigarette packaging foils reaches 35,000 tons, accounting for 60 percent of the total consumption of double-null foils. The third is about decorative foils, which are mainly used for heat insulation, moisture-proof and decorative materials. At present, the application of decorative foils in China's construction and home appliance industries is increasingly widespread; the fourth is cable foils, which mainly use the hermeticity and shielding of aluminum foils. Sex, as a protective layer of cable. The above four aluminum foil consumption accounted for more than 70% of the total aluminum foil consumption in China. In addition to cigarette packaging, aluminum foil applications in the packaging industry include: aluminum foil caps for high-end beer, aluminum-plastic composite bags, pharmaceutical aluminum foil blister packaging, and chocolate packaging.
According to statistics, there are currently 83 aluminum foil manufacturers in China with an annual production capacity of about 235,000 tons. Although some enterprises have some modern production equipment, most aluminum foil manufacturers have small scales, and there is still a big gap between equipment and technology level compared with developed countries. There are many middle- and low-end products and few high-end products. Therefore, from the perspective of development prospects, China's aluminum foil market has great room for development both in terms of consumption and product quality.