Hot foil troubleshooting and influencing factors

The bronzing suitability refers to the selection of the type of anodized aluminum and the matching between the bronzing speed, temperature, and pressure. In the case of fixed hardware such as equipment, proper control of bronzing suitability is the most important means to improve bronzing quality.

1. Hot stamping is not true or hot stamping is not true

This is related to the surface characteristics of the print, the nature of the electro-aluminum, the hot stamping temperature and pressure and other factors. 1 The surface of the print is dusted too much or the surface contains additives such as a releasant and a bright paste, which will hinder the adsorption of the aluminum foil and the paper. The solution: surface powder removal or solution in the printing process. 2 The improper use of anodized aluminum directly affects the fastness of hot stamping. According to the size of the bronzing area, the characteristics of the stamped material should be considered in consideration of what type of galvanized aluminum is selected. Domestic aluminum products are mainly peacock brand series produced by Shanghai Shenyong Hot Stamping Material Co., Ltd., and imported aluminum products are mainly PMK and LK series from Germany KURZ, Japan's A, K and H series, and KOLON's SP series from South Korea. .

Electro-aluminum matching can be mainly referred to the following classification: General hot stamping products (generally black) Electro-aluminum type 88-l, KURZ PM type; cigarette packs, cosmetics and other ink-colored prints (including gold, silver) Gilding anodized aluminum type 88-2; cigarette markings, cosmetic packaging and other fine handwriting hot stamped anodized aluminum 88-3, 88-4, PM288; suitable for OPP or PET laminated paper and UV ink cardboard , glazing paper and other products stamping Electro-chemical aluminum 88-4, K series, LK series, and SP series. 8 It is not possible to correctly grasp the matching between hot stamping equipment and hot press time and hot stamping temperature, which will affect the fastness of the stamping and the sharpness of the graphic outline.

Due to the different equipment and hot stamping materials, the hot pressing time and hot stamping temperature are not the same. For example, a high-speed circular press has a fast speed and the embossing line contacts. The hot stamping temperature is higher than that of a round press or a flat press. Under normal circumstances, the round stamping hot stamping temperature is between 190°C and 220°C, the rounding pressure is approximately between 130°C and 150°C, and the flattening is approximately between 100°C and 120°C. Of course, hot pressing time, hot stamping temperature and production efficiency are also largely constrained by the transferability of the electro-aluminum.

2. Pull back

Reverse pulling refers to that after the hot stamping, the electro-aluminum pulls the printing ink or the printing oil on the printing. The main reason is that the ink on the surface of the printed product is not dry or the post-processing of the surface of the printed product is improperly processed, which results in the ink on the surface of the printed product, the UV oil and the surface of the paper are not firmly bonded together. Solution: After the prints are dried and then hot gold. In addition, it is possible to use electro-aluminum with low electro-aluminum separation and excellent heat transfer.

3. Paste-printing and hot stamping of electro-aluminum discoloration pastes are mainly caused by poor bronzing production, looseness of the installation of anodized aluminum, or improper foiling of anodized aluminum. After the stamping, the discoloration of the electro-aluminum is mainly due to the high stamping temperature. In addition, the wrinkling of the aluminum foil is also likely to cause discoloration due to uneven color stamping, which can be solved by appropriately lowering the temperature. For the round-flattening model, fans can be installed at the foil feeding place to keep the foils from floating, avoiding the aluminum foil touching the hot stamping and scorching before the stamping.

4. Inappropriate process arrangement destroys the luster of the surface of the electrochemical aluminum

Need to cover film processing bronzing, people often worry that gold foil is easy to wipe and then hot stamping and then film, which easily lead to: 1 film (especially matt film) will destroy the surface of the aluminum luster, should not use water-soluble glue film , otherwise it will cause the surface of the aluminum foil to be black, and at the same time, it can easily cause the gold powder to stick to the edge of the picture and cause the phenomenon of hair crazing. 2 After the bronzing, the dent is caused by the pressure, and the glue is not easy to penetrate the surface of the galvanized aluminum, which can easily cause separation of the OPP from the bronzing office and affect the product quality. The correct process is to apply foil and then hot stamping, choose the matching of aluminum and OPP. In short, there are many factors that affect the quality of bronzing. Making high-quality bronzing plates and correctly grasping bronzing suitability are the key to improving the quality of bronzing.