This is a kind of auxiliary agent for light-colored inks. The main function is to reduce the ink color intensity, and can basically maintain the ink's ink (viscosity, fluidity) and printing performance.
Such adjuvants include white ink with strong hiding power, transparent and translucent white oil, Vely oil, bright light, and zero oil. At the same time there are solvent dilute in the ink, such as ink transfer. This is an auxiliary agent that is necessary to achieve a certain process design. The properties of each are very different, and care should be taken during use.
White ink, all kinds of ink has its own white ink, it dilute strong, but the texture is heavy. If it can be used in a larger amount in the letterpress, then the use of light colors in offset printing should be used sparingly or in combination with transparent and translucent types. If used in large quantities, the transferability and printing effects are poor. In particular, the appearance of cloud-like spots in the printing, at the same time, the hydrophilicity of titanium dioxide, easy to cause emulsification, dirty version and other problems. It is true that white ink is an indispensable material to dilute.
White oil is also used for diluting purposes. It is mainly used in oil type and oleo type inks. Offset printing and lead printing are available.
One is a dispersion type slurry translucent body, which is formed by dispersing aluminum hydroxide, barium sulfate and titanium dioxide in a varnish and wax oil. This material can be used for lighter colors or primers in higher grade products.
One type is an emulsified pasty translucent body, which is obtained by heating saponification of magnesium carbonate, stearic acid, and polymeric oil. The cost is low and the process is relatively simple, but it is unstable and has a great influence on the printing performance. Can only be used for low-grade prints or for treating paper surfaces.
As for their dosage, they are determined according to the light-colored requirements. Fine prints are not suitable so as not to affect gloss and other qualities. At the same time, dry oils (or heat energy) must be used in combination with dry oil or other methods.
Transparent oil (Vireol oil), which is a dilute auxiliary with a large amount of use and a wide range of uses. It is characterized by good transparency and excellent printing performance. The disadvantage is that it affects drying. It is made of aluminum hydroxide with appropriate water content and dispersed in a binder by a three-roller ink in a transparent slurry. It is light in color, resembles offset printing, printing ink, and is also known as colorless ink. The only reason why the link material is transparent is that the refractive index of aluminum hydroxide is similar to or equal to the refractive index of the linking material.
The type of binders has expanded from pure oil type to resin type. The use of transparent colloidal calcium carbonate with aluminum hydroxide or a single use of the material, the improved adjuvant, to improve the viscosity of the ink, increase the gloss than pure aluminum hydroxide and transparent oil for transparent oil much better.
Transparent oil is generally used to formulate light-color inks for offset printing or lead printing. It has little effect on color, and it can also play a role in glossiness and printability on general prints. However, it should be noted that since the aluminum hydroxide-based amphoteric hydroxide reacts with both the acid and the base, it causes the ink to gel and swell. Therefore, it is not necessary to store long-term storage for existing products. In addition, for inks such as golden red, blue light, blue iron, and blue lotus, if they are used to dilute it, it will cause dull or faded colors. Taboo to use. At the same time, due to poor water resistance in offset printing, it can also cause problems such as emulsification.
Zero oil, in addition to diluting, is mainly used to adjust the thin and fluid ink body.
Another product in the diluting agent (dissolving agent) is derived from the requirements of high-quality products and the need to adjust the ink property, and is specially produced by matching production. Such as bright light, bright light agent.
Most of these diluting agents are paste-like transparent bodies made of rosin-modified phenolic resins, gel-forming materials, dry vegetable oils, ink oils, etc., or materials other than the above materials, such as dispersed calcium carbonate. , into a semi-transparent paste adhesive. It is used with advanced inks with light color inks. At the same time, it has good brightness, good water resistance and printability, can play bright light, and increase the impression of three-dimensional impressions. With some fine prints and trademarks, it is also possible to adjust the inkiness of large, less-tacky inks within 3%.
When using such dilutants, the following points must be noted:
First, with light-colored ink, such as small red, small blue, etc., in the permeability of the coated paper printing, generally do not add drying oil; if the temperature is low, high humidity, or printing is not long, generally not Add dry oil; if the temperature is low, humidity is high, or the print is not long, depending on the pattern of the printed product, it must be accompanied by 0.5-3% of white dry oil, or red dry oil must be appropriately reduced.
Second, if you feel that the viscosity is relatively large and dilute, you must also use a small amount of detackifier. If the viscosity is large, and the ink is thick, you must add resin thinner.
Third, the amount to dilute to the color you want to reach.