Permanent Finishes on Viscose Rayon depending on Cross–bonding

Abstract

Evidence is presented which demonstrates the existence of cross–bonds in the molecular struoture of nine modified viscose rayons. In a resin treatment, e. g. the urea–formaldehyde anti–crease process, the greater part of the material is deposited between the molecules of cellulose in the amorphous regions of the fibre. The change in fibre properties, however, is due mainly to a muoh smaller amount of reaotant actively cross–bonding adjacent molecules. In technically important modifications of viscose rayon there is one cross–bond to each 40–100 glucose residues of the fibre cellulose. In the majority of instances the behaviour of the cross–bonds can be adequately represented by definite structural formulae. The cross–bonds studied differ widely in stability, and the technical importance of this point is indicated. The teohnical processes depending on cross–bonding are reviewed, and the anti–crease process is discussed.