Packaging material performance requirements-- The printing performance
Author:plastic bag wholesaler Time:15/07/07 Click:
Packaging material performance requirements-- The printing performance
Packaging needs to pass the necessary information to consumers via print, to stimulate consumer desire to buy. Flexible substrates typically include BOPP, PET, PA, PE, among BOPP and BOPET as the main substrates, their tensile strength, elastic modulus that is, should not be deformed, high overlay accuracy. But polar BOPP and BOPET processing are relatively low, especially surface tension PP film only about 28 xl0 -5N, if the direct printing ink adhesion is poor, and therefore PP and PET prior to printing generally need to go through electric corona treatment, the surface tension of the film increased to 38 ~ 44 × 10 -5N, we can ensure good ink adhesion strength.
Even PA film as substrates, corona treatment also needs to surface tension above 45 xl0.5N. Pigment ink (dye), binder polymer have strong polarity, the polarity of the ink and therefore is generally relatively large, according to "like dissolves like" principle, and only the film after corona treatment can produce good ink The bonding effect (compatibility).
Note that the choice of inks, printing inks need to match the type of substrate, e.g., chlorinated polypropylene (CPP) is generally suitable for printing ink PP or PE, and polyurethane (PU) are more suitable for printing inks PET or PA, high-temperature cooking printed bags you need to select a two-component PU ink curing agent required linear PU prepolymers crosslinked into a network molecular structure.
