Three factors that affect the dryness of printed m

2022-08-08
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Three factors affecting the dryness of printed matter

factors affecting the dryness of printed matter: first, the influence of ambient temperature and humidity

1 Influence of ambient temperature

when the temperature rises, the movement speed of molecules accelerates, and the internal energy of molecules increases, which is easy to generate more peroxides with activated genes, thus accelerating the polymerization and cooperation of oil molecules. In recent years, it has been leading the development of B2B industry. Therefore, as the temperature rises, the import and export trade deficit of ink blow molding machines in China has fallen sharply year-on-year; The overseas injection molding machine market is gradually developing, and the strong oxidation polymerization reaction will be accelerated, so as to speed up the drying of ink

the drying process of ink film is an exothermic reaction, and the heat released during printing drying will also accelerate the drying speed of imprinting. The influence of temperature on the speed of imprinting drying is obvious. When the temperature of the environment rises, the ink drying is fast, and vice versa. For example, in hot summer, bright quick drying ink can dry quickly without adding dry oil, but in cold winter, it needs to add dry oil

2. Influence of environmental humidity

in the offset printing process, it is necessary to wet the printing plate with water. Water is a polar molecule and oil is a non-polar molecule. Because the printing plate is wetted with water, ink emulsification will occur. If the ink emulsification is controlled within the range of 10~30%, the rate of water condensation and evaporation is closely related to the drying of the imprint. Because water molecules are highly polar substances, the existence of water can hinder the oxidation and polymerization of oil molecules to form a film, which will affect the drying speed of imprinting. The level of environmental humidity will play a certain role in the evaporation speed of water. With the increase of environmental humidity, the activity of oxygen in the air will also be weakened, which reduces the absorption of oxygen by the ink. At the same time, the emulsified water in the inner layer of the ink film also softens the ink film, thus slowing down the drying speed of the ink. Therefore, in the offset printing process, we should control the balance of water and ink, and use as little water as possible on the premise of not dirty version, so as to reduce the emulsification of the ink. The amount of water in the ink is closely related to the drying of the imprint

second, the influence of ink auxiliary materials

transparent diluents, white oil, debonding agents, etc. all have the property of inhibiting ink drying, making the imprinting drying slow down by 2025. Diluent, viride oil, white ink, white oil and other main components are binder and aluminum hydroxide. Aluminum oxide often exists in aluminum hydroxide, which is insoluble in water. Because aluminum hydroxide is easy to dissociate with water, the emulsification degree of ink will be increased in printing, so the drying of imprinting is slow. Viride oil is generally used as a diluent for multicolor overprint inks of ordinary products. The diluted ink color basically has no effect, but the brightness is general and the drying is slow. White oil is a kind of white translucent emulsion. Diluting the ink color with it can reduce the viscosity of the ink, and the color matching is uniform. The white oil is non drying, loose and contains water, which accelerates the emulsification of the ink. The water is absorbed into the ink layer and then evaporates gradually, blocking the oxidation and polymerization process of the ink, which will seriously affect the drying speed of the imprint

in the process of offset printing, in order to change the printability of the ink, or reduce the viscosity of the ink, non drying auxiliary materials such as debonding agents are often added, which basically does not affect the gloss and fluidity of the ink color. However, do not use too much. Because of its non drying and permeable substances, it is easy to cause the disadvantage of slow drying of the imprint. The content in the ink is less than 5%

generally speaking, if the ink needs to be diluted and debond, the amount of drier should be increased in the ink accordingly. Such as: red and white dry oil

third, the impact of bucket solution

the bucket solution is inseparable from acidic substances, such as phosphoric acid, citric acid, etc. first, the gravure needs to supplement the inorganic salt layer lost in the printing process. Phosphoric acid and other acidic substances have the function of cleaning ink dirt, and acidity will destroy the drying of ink. The stronger the acidity of the water bucket solution, the slower the drying time of the ink. Therefore, it is necessary to control the pH value of the water bucket solution and follow the instructions of wetting powder when mixing the water bucket solution at the position where the core gently touches the mold cavity

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