1. can use vinyl release. cleaning is convenient
2. quick-drying. Pigments in the pen after a few minutes to dry, don't like paintings that completion required several months to finish. Like slow drying characteristics of paint painter pigment retardants to slow the drying time available.
3. coloring layer will swiftly lose soluble, as well as tough, elastic, impermeable membrane. This film is similar to rubber.
4. color full, strong, fresh energy no matter how to reconcile are not "dirty" and "gray" feeling. Coloring layer never had oil fouling phenomena.