What are the requirements for printing paper cup machine ink?
The printing ink of the paper cup machine requires good printing fastness, and the printed matter has good acid resistance, alkali resistance, water resistance, temperature resistance, and light resistance, and will not fade, change color, or fall off due to the effects of these factors; in addition, the printed matter must have good scratching Trace and gloss, semi-dull and matt.
The following points should be paid attention to in the ink printing of the paper cup machine:
Ink components: The components of the ink must comply with the Food Sanitation Law and the corresponding food packaging sanitation standards.
Residual solvent: control the amount of residual solvent to be small to prevent the printed matter from odorous, smearing on the back of the printed matter, and when the solvent adheres to the substrate or base film of the sealing part, it will cause poor heat sealing, resulting in poor adhesion at the sealing part Or the phenomenon of roll mouth bursting caused by poor adhesion.
Drying temperature: The ink drying temperature should not be too high. When the temperature is too high, over-oxidation will occur on the surface of the base film, resulting in poor heat sealing. But it is also necessary to prevent the printing ink from drying badly to avoid odor.
Selection of ink and ink solvent: The selected ink solvent should not swell the PE film or contain water in the solvent to prevent the printed matter from curling; as far as possible, use the ink containing a plasticizable free carrier to prevent the ink film and PE film from being generated due to temperature changes. The shrinkage is different, resulting in curling of printed matter. The curled printed matter will be warped after die-cutting into fan-shaped pieces, which will bring difficulties to the conveying and roll forming of paper cups.
Ambient temperature and humidity: Too high humidity in the workshop will cause prints to curl. If the temperature of the roll film after printing is too high, adhesion between the upper and lower layers of the film will occur, which will also affect the subsequent paper cup processing and forming.