Retail Soft, Soft Hand are two common names associated with this type of decoration. By use of high mesh screens and a mix of regular plastisol inks with a softener additive, the print becomes softer but at the same time it turns semi transparent letting the color of the shirt show through a lot more compared to a print using underbase. See image on right side.
In order to fully understand this process, you can open the link below to read a great article published by Tara Danzig of Promo Marketing Magazine.
Excel offers a hybrid version of plastisol/chino inks and high mesh screens to obtain great looking prints with a Retail soft feel.