Porous eyelash better absorbs glue, which provides a strong bond with artificial. And if the eyelash flakes tightly fit together, then the glue is more difficult to penetrate the structure of the hair and, accordingly, the eyelashes don't remain long.
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And now what can we do? Use a pre-treatment to increase the lash porosity: it will help the glue penetrate deeper (by the way, the RQL pre-treatment contains more than 50% alcohol, unlike many others), and the primer will improve polymerization and adhesion will be much better.