Abstract: A first yarn (21) undergoes a pretreatment process (22) for saturation with a pretreatment solution. In the pretreatment process, the first yarn is supplied to continuously travel through a first bath (100.sub.2) and a second bath (100.sub.3) of the pretreatment solution. The first bath has a volume (V.sub.2) which is less than a volume of the second bath (V.sub.3). Between the first and second baths the pretreatment solution is impressed into the continuously moving first yarn. After the second bath only excess pretreatment solution is removed from the moving yarn, thereby keeping the yarn saturated when it enters a heat treatment (42) for locking the pretreatment solution into the yarn. The first yarn can be subsequently dyed in the same operation or maintain its original appearance (either colored or non-colored). The first yarn can be a warp yarn or weft yarn which, together with either a second yarn (weft or warp yarn, treated or untreated), is woven into a fabric piece (26).