The adaptability of the aluminized paper is rather special, and the aluminized layer on the surface has metal characteristics. In the printing process, the characteristics of the surface of the aluminized paper and the printability of the printed material such as the printing ink occur: self-connection. Therefore, the printing adaptability of the aluminized paper is actually easier to grasp than the printing adaptability of the aluminum foil. Aluminized paper has high surface strength, it can adapt to the speed of high-speed printing presses, and it can also withstand the pulling force generated by the value-added of ink stickiness. It has good adaptability to improve production efficiency and stabilize printing quality. Aluminized paper surface tension is conducive to the transfer of ink during printing, printing ink film flat, smooth, clear and complete graphics. The aluminized paper has a relatively compact structure with essentially no gaps and its surface is similar to a mirror surface. Therefore, aluminum-plated paper does not have absorption properties like ordinary paper and has low absorption.
The color arrangement of printing should generally highlight the main style of the design. In the printing, the color of the first printing and the color of the after printing are different due to the color sequence. The effect is also very different; the absorption performance and drying performance of the aluminized paper In terms of particularity, it is recommended that the printing of multi-color printing presses should follow the following points: Colors that are dark in color and small in area should be printed in advance. Generally, a large-area background color should be printed in the final print. Such as the first printing a large area on the ground, will cause the back of the color overprint is not on, but also easy to scratch the back of a few colors in the back of the printing, scratching the surface of the background color, resulting in a decline in product quality, affecting the appearance and design effects. The main colors should be printed at the back. Generally completely transparent ink does not exist, the hue of the printed product tends to favor the hue of the post-printing color; the color of the overprinting accuracy should be printed first. Because aluminum-plated paper has the dual physical properties of metal and paper, it should be printed on the front with a high-precision color. There are strict requirements in the design of cigarette packs and beer bottle stickers. When designing manuscripts, it is necessary to fully consider the lines of the printed products and the automatic packaging lines to avoid unnecessary losses.
In terms of the ink and drying requirements for printing aluminized paper, penetration is the basis for fixing the ink on the substrate. The fixing speed is the condition of the ink: dryness in the factory, and the drying time is the key to the ink conjunctiva. Infiltration is the basis for fixation. In resin inks, the binders for high-grade inks consist mainly of resins, dry vegetable oils, and pigments. Fixing speed is made by pigment oil on the substrate. It is determined by the instantaneous amount of penetration, but also relates to the drying time of the ink. In order to penetrate the ink, it is necessary to have substrates with good absorption properties. However, the absorption performance of the aluminized paper is not ideal, whether it is the use of fast-drying, bright fast-curing offset inks, or special offset inks for synthetic paper, plating. Aluminum ink still has liquid solvents after it is inked. This kind of ink is not only the main cause of product stickiness, but also the cause of poor drying. To avoid sticking and improve drying performance, special inks must be used.
POP ink is an ideal choice for aluminized paper printing. The main advantage over other inks is that other inks cannot be applied to vacuum aluminized films, gold and silver cardboards, films, synthetic papers, and various non-absorbing materials due to adhesion and drying problems. Printed on the material. Therefore, it is better to use POP ink when printing non-absorbent materials. Compared with UV ink, POP ink price is only one cow of UV ink, and the color is brighter than UV ink and it is not easy to crack. POP inks can be printed with a general offset press. Unlike UV inks, they require a high-power light curing machine. Printing presses for POP inks do not need dedicated ink rollers, blankets, blister covers, washing water, etc., but UV inks are different. All consumables need special and the price is more expensive than POP inks. Therefore, using POP ink has a certain price advantage. In the process of using POP inks, the minimum amount of dampening water should be controlled. The pH is generally between pH 5-6. The dampening water temperature cannot be too high, otherwise it will cause emulsification, generally between 10-15%. In the case of adding desiccant or other auxiliaries, the addition amount must not exceed 2%, and the speed should not be too fast, preferably controlled at 8000-10000 pcs/h. Printing shop temperature and humidity can not be too high, otherwise it will make the layout of the water in the 25-28 ~ C, humidity of about 60%.
Fourth, aluminum coated paper conforms to the trend of environmental protection
As far as cigarette packs are concerned, Chinese tobacco packaging has been moving from soft packs, ordinary white card hard packs to glass cards, and popular aluminum foil gold and silver cardboard in recent years, and high-grade matte technology using PET composite cardboard. The forefront of the packaging industry. Although aluminum foil gold and silver cardboard and PET composite paperboard have become high-grade packaging materials with good decorative performance and anti-counterfeiting performance, they are non-environmental materials. In order to meet the requirements of environmental protection and reduce the need for packaging costs of cigarettes, it is an inevitable trend to replace aluminum foil cardboard and aluminized gold and silver cardboard with aluminum-coated cardboard.
The biggest advantage of composite aluminum foil liner is good moldability and excellent sealing. At present, aluminum spray paper not only meets the requirements of cigarette packs in terms of performance, but also the aluminum layer thickness of aluminum spray paper is only 1/200 of composite aluminum foil and weighs only 1/125. In the transfer of aluminum spray paper, due to solving the problems of brightness, folding resistance and printing adaptability, compared with the aluminum foil composite card, PET composite “paperboard†(commonly known as “bright cardâ€), it has a better cigarette pack formability, No burst, no deformation, aluminum foil, gold and silver cardboard can neither be recycled as aluminum products, nor can it be recycled as paper.PET composite cardboard is a composite film of aluminum film and paper, plastic film can not be degraded, and it is not conducive to The government of developed countries used taxation policies to promote the use of environmentally friendly materials, making aluminum-sprayed liners widely used in recent years, because aluminum-sprayed liners were classified as single-material, with a mark of 0.4. / Kilograms of taxation, and aluminum foil compound lining paper as a composite product, with a taxation of 2.10 marks / kg. This legislation has an explosive impact in the cigarette industry, the original aluminum foil composite paper packaging materials began to aluminize Paper transfer, aluminum spray paper and transfer aluminum spray paper have also begun to receive widespread attention and application in China, especially in cigarette package materials.After solving a series of printing and forming technical problems, aluminum spray paper In particular, the transfer of aluminum spray paper has been applied to cigarette packs on a large scale.
The aluminum layer of aluminum lining paper is 0.02μm thick, and the thickness of aluminum foil composite lining paper is 7μm. The difference between the two is more than 300 times. The resource name of aluminum lining paper lining is less than that of aluminum foil compound lining paper. However, their appearance and barrier properties of steam, water, and light are almost the same, and aluminum-sprayed liners are more likely to be recycled, burned, and easily oxidized and degraded after disposal. After the cigarette box is discarded, its aluminum layer is oxidized in a short period of time and will not cause environmental pollution. The waste can also be collected. Send paper mills for recycling. The price of sprayed aluminum paperboard is 10% lower than that of aluminum foil paperboard. The speed of cigarette packaging machines printed on sprayed aluminum paperboard is significantly higher than that of cigarette papers made of aluminum foil composite paperboard (approximately 200 bags/minute higher). Due to the above reasons, the widespread use of sprayed aluminum paperboard will also form a trend.
Author/Hu Zhipeng
Source: Aluminum Processing - Issue 1, 2006