Test Ink is a standardized fluid used to determine the surface energy of a substrate that is to be coated. Test Ink can be used for testing during a process as well as for inspection of incoming goods and quality assurance purposes.
Fluids with progressivley higher surface tension are applied to the surface of the product. The behavior of the rim of the test Inks brush stroke within the first two seconds after applying, determines the surface energy of the sample.
Series A inks according to DIN ISO 8296 and ASTM D 2578-99a. These blue inks are a mixture of formamide and ethyl glycol (toxic) in varying proportions. They cover the surface energy range of 30 – 58 mN/m. This ink type is the standard type and most widely used on the market. They are suitable for PE, PP and similar substrates. For PU and soft PVC these inks cannot be used.
Series B inks are a methanol-water mixture according to DIN 53364, Series B and DIN ISO 8296, red. Depending on the methanol content, the liquids are more or less toxic. With them the range of 23 – 72 mN/m is covered. They can also be used for soft PVC.
Series C inks are also red in color and are a mixture of ethanol and water. This ink series is harmless to health and was developed in accordance with DIN ISO 8296.It is available with surface tension values from 30 – 72 mN/m. This type of ink is gaining more and more acceptance on the market due to their physiological harmlessness and can be used for all substrates.
The E series corresponds to the alkane series with the following surface tensions: 16, 18, 20 and 25 mN/m. The polarity of these clear liquids is zero.
Series F is a water-boiled salt mixture covering values above the water wettability of 72 mN/m at 77 and 82 mN/m.