Factors affecting the
Ink drying is mainly determined by the type of linker and its properties.Water-based printing inks of different models or varieties, the composition of the binder, its drying form and drying performance is not the same.Such as resin ink drying than oil ink, which is due to its linker containing resin components;When the proportion of the linker containing drying oil increases, ink drying speed decreases accordingly.In addition, the drying ink is also affected by multiple factors, so that the ink drying rate changes.
1. Influence of pigment on drying property
Ink oxidation polymerization reaction is in the presence of pigments and fillers and other solid dispersion phase.Different pigments have different effects on the oxidative polymerization of ink.Some pigments are inert, ink drying has no obvious impact.Some pigments have drying effect, their drying mechanism and desiccant similar, but drying ability is much weaker.
Gravure water - based plastic table printing ink
Most organic pigments on the ink oxidation polymerization drying resistance, especially the pigment molecular structure contains phenol, phenol, naphthol, amine, aniline and other groups, can inhibit the binders for oxidation polymerization reaction.So with these pigments prepared by the oxidation of conjunctival drying ink.The drying speed is slow.Common hindrance ink oxidation drying pigments are carbon black, titanium white, azo red and phosphorus tungsten molybdenum salt precipitation pigments.The proportion of pigment in the ink and its dispersion is also related to the ability of ink penetration and penetration rate of drying.Pigment proportion, fine particles, uniform dispersion of binders penetration of resistance, and pigment particles formed by the capillarity of strong, so the binders of permeability, the corresponding ink drying also decreased.
2. Ink adjuvant effect on drying
In the process of printing ink to add dictation adjuvant to adjust printing suitability.Various adjuvant composition and properties of different ink drying effect is also different.In addition to desiccant can improve ink oxidation conjunctiva drying speed, other auxiliary agents some can speed up the drying speed of ink, some can inhibit the drying of ink, ink drying speed.
3. Influence of temperature on drying
Printing environment temperature rise, ink drying speed.About temperature rise every 10 ℃, water-based gravure plastic composite ink oxidation drying can shorten the time needed for half.When the temperature rises, the chemical activity of the substance molecule increases, the reaction rate of the dry oil molecule and oxygen is accelerated, and the production of peroxide in the oxidative polymerization is also increased, which can accelerate the polymerization of the oil molecule.In addition, when the temperature increases, the speed of molecular movement, energy increase, can improve the volatile solvent in the linker, thereby improving the drying ink drying and drying speed.
Gravure water - based plastic compound ink
4. Influence of humidity on dryness
Printing environment humidity on the ink drying effect.When the ambient temperature increases, ink drying speed slows down.Relative humidity affects the main ink oxidation drying speed conjunctival, this is due to an increase in the content of water vapor in the air, the chemical energy of oxygen in air is abate, the amount of oxygen is relatively less contact with ink, paper moisture content also increase, compared with the relative humidity is low, paper absorption of links to reduce, make the ink penetration, condensing capacity has also dropped, causes the ink dry.
5. Influence of paper properties on dryness
Paper performance is one of the important factors affecting ink drying.Paper moisture, ink absorbency, compactness and size and ink penetration and penetration rate is closely related to these different properties of paper, ink penetration drying and condensation drying speed.Paper moisture content is too high, water evaporation will hinder oxidation polymerization, slow down the drying speed of ink.Therefore, ink in the nature of the paper printed on the performance of drying are not the same.
In addition to the factors mentioned above, there are also the effects of the acidity of the wetting solution on drying, the thickness of the printing ink layer and the number of times of double ink printing on drying, etc., different printing environment also has a certain impact on the drying of ink.The air circulation of the printing environment, so that the oxygen content in the air is sufficient, and oxygen can be constantly supplemented, so that the ink oxidation polymerization rate.In addition, air circulation can also improve the volatile speed of solvent, ink volatile drying ability.