The analysis of the causes of aluminum foil membrane spots - — Food packaging manufacturer

Aluminum foil membrane causes of spot analysis believes that many aluminum foil membrane manufacturers in the production of aluminum foil membrane will encounter a problem, that is a composite good aluminum foil membrane surface can have spots, so this is why? Do you have any good solution? Today the packing small make up will lead us to study the knowledge. Aluminum foil membrane surface can appear sometimes white or gray spots, this kind of situation in the full version of the printing ink and composite aluminum plating film to live in a production process, the main reason has the following several aspects. （ 1) Lower the surface tension of the ink, resulting in poor performance of the adhesive coating, glue, so the bond force between ink and aluminized layer and interlayer tightness will be different, thus aluminized layer on the surface of the reflective effect also has strong with the weak, forming white or gray spots on the vision. （ 2) The covering power of ink is not strong or poor flowing property, causing uneven cover ( Especially the white ink and light yellow ink) 。 Where the cover effect is not good, the color of the aluminized layer through the ink penetration. （ 3) Adhesive concentration is too high, viscosity is too large, easy to printing ink adhesion to the adhesive solution, make the change the color of the printing layer. At the same time, the adhesive viscosity if it is too big, liquidity is poor, easy to cause uneven glue, influence on the performance of the aluminized layer surface reflective, spots. （ 4) Do not match, inks and adhesives made the adhesive on the ink penetration performance is bad, rejection, also can produce spots. （ 5) Aluminum foil membrane drying incomplete, inadequate solvent evaporation, causing residual solvent in the adhesive is too much, part of the ink layer was dissolved glazing, thus forming spots, serious when also can form of many tiny bubbles after curing. （ 6) Aluminum plating film itself quality is poorer, more pervious to light point, after composite have different due to the reflectivity of aluminized layer, formation of spots. （ 7) Bake, ( Especially the primary drying tunnel) Gel temperature is too high, resulting in surface liquid dry too fast, conjunctival surface; As the internal solvent in secondary and tertiary bake, gasification occurs, will break through the surface of the film, crowded up glue adhesion agent, printing ink, rubber thickness caused by uneven, resulting in a spot.