The most prominent view of the diffusion mechanism of dyes into wool fibers assumes that the molecules primarily enter the fiber in a fast process along the cell membrane complex (CMC), that is, by an intercellular mechanism. From the CMC, they are subsequently distributed in a slower process throughout the other morphological components according to their respective diffusion coefficients and dye affinities. This view, referred to here as the CMC-diffusion model, is based on investigations of the diffusion performance of heavy metal complex and fluorescent dyes under anhydrous and aqueous conditions. An evaluation of various key aspects of the evidence for this model suggests that, due to differences in the glass transition and fluorescence quenching performance of the various morphological components in a wool fiber, there is, in fact, little evidence to support the CMC-diffusion model. Instead, the evidence supports the alternative, more general view that under normal dyeing conditions, diffusion proceeds primarily by means of all the nonkeratinous components of the wool fiber according to a restricted transcellular diffusion mechanism.
BradyP. R., Penetration Pathways of Dyes into Natural Protein Fibres, in “Proc. 8th Int. Wool Text. Res. Conf., Christchurch, NZ,” vol. IV, 1990, pp. 217–226.
3.
BradyP. R., Diffusion of Dyes into Natural Fibers, Rev. Progr. Coloration22, 58–78 (1992).
4.
CollinsS.DavidsonS.GreavesP. H.HealeyM.LewisD. M., The Natural Fluorescence of Wool, J. Soc. Dyers Color.104, 348–352 (1988).
5.
CowgillR. W., Fluorescence and Protein Structure, Part XI: Fluorescence Quench by Disulfide and Sulhydryl Groups, Biochim. Biophys. Acta140, 37–44 (1967).
6.
FeughelmanM.DruhalaM., The Lateral Mechanical Properties of Alpa Keratin, in “Proc. 5th Int. Wool Text. Res. Conf., Aachen,” vol. II, 1976, pp. 340–349.
7.
FraserR. D. B.MacRaeT. P.RogersG. E., “Keratins,”C.C. Thomas Publ., Springfield, Ill., 1972.
8.
HalyA. R.SnaithJ. W., Heats of Fusion of Various Amounts of Absorbed Water in Wool Keratin, Biopolymer7, 459–474 (1969).
9.
HalyA. R.SnaithJ. W., The Specific Heat of Modified Wools and the Heat of Fusion of Absorbed Water, Appl. Polym. Symp.18, 823–834 (1971).
10.
HöckerH.ThomasH.KüstersA.HerrlingJ., Färben von plasmabehandelter Wolle, Melliand Textilber.75, 506–512 (1994).
11.
HoltL. A.SaundersJ. A., A Fluorescence Microscopy Study of the Diffusion of Some Nonionic Compounds into Wool from Solvent Mixtures, Textile Res. J.56, 415–418 (1986).
12.
HorioM.KondoT., Crimping of Wool Fibers, Textile Res. J.23, 373–386 (1953).
13.
JurdanaL. E.LeaverI. H., Penetration of Alcohols into Wool and Hair as Studied by Fluorescence Microscopy, Textile Res. J.62, 463–465 (1992).
14.
KlotzM.-L.AltenhofenU.ZahnH., Untersuchungen zur Funktion der Nichtkeratinproteine der Wolle beim Färbeprozess mit einem Säurefarbstoff, Textilveredlung21, 119–121 (1986).
15.
LeederJ. D.RipponJ. A.RotheryF. E.StapletonI. W., Use of the Transmission Electron Microscope to Study Dyeing and Diffusion Processes, in “Proc. 7th Int. Wool Text. Res. Conf., Tokyo,” vol. 5, 1985, pp. 99–108.
16.
LeederJ. D., The Cell Membrane Complex and its Influence on the Properties of the Wool Fibre, Wool Sci. Rev.63, 3–35 (1986).
17.
LeederJ. D.HoltL. A.RipponJ. A.StapletonI. W., Diffusion of Dyes and Other Reagents Into the Wool Fibre, in “Proc. 8th Int. Wool Text. Res. Conf., Christchurch, NZ,” vol. IV, 1990, pp. 227–238.
NordonP.MackayB. H.DownesJ. G.McMahonG. B., Sorption Kinetics of Water Vapour in Wool Fibres: Evaluation of Diffusion Coefficients and Analysis of Integral Sorption, Textile Res. J.30, 761–770 (1960).
20.
PailthorpeM. T., The Theoretical Basis for Wool Dyeing, in “Wool Dyeing,” ch. 2, LewisD. M., Ed., Soc. Dyers Color., Bradford, U.K., 1992, pp. 52–87.
21.
RipponJ. A., The Structure of Wool, in “Wool Dyeing,” ch. 1, LewisD. M., Ed., Soc. Dyers Color., Bradford, U.K., 1992, pp. 1–51.
22.
RipponJ. A.HarriganF. H., New Method for Dyeing Wool at Temperatures Below the Boil, Wool Rec. (4), 53–55 (1994).
23.
RipponJ. A.HarriganF.-J., New Process for Dyeing Wool at Low Temperature, Int. Dyer (7), 20–25 (1994).
24.
SiderisV.HoltL. A.LeaverI. H., Dye Diffusion in Wool and Selective Modification of Various Morphological Components of the Fibre, in “Proc. 8th Int. Wool Text. Res. Conf., Christchurch, NZ,” vol. IV, 1990, pp. 207–216.
25.
SiderisV.HoltL. A.LeaverI. H., A Microscopical Study of the Pathway for Diffusion of Rhodamine B and Octadecylrhodamine B Into Wool Fibres, J. Soc. Dyers Color.106, 131–135 (1990).
26.
SiderisV.LeaverI. H.HoltL. A.JonesL. N., Photomodification of the Cell Membrane Complex of Wool—The Effect on Dyeability, J. Soc. Dyers Color.108, 436–440 (1992).
27.
SimpsonW. S., Fluorescence Properties of Wool and Other Animal Fibres, Wool Res. Org. New Zealand, Communications C122, pp. 1–36, 1992.
28.
StootmanF. H., The Self-Diffusion of Plasticizers in Wool Keratin, Doctoral thesis, University of NSW, Sydney, Australia, 1977.
29.
SwiftJ. A.AllenA. K., Swelling of Human Hair by Water, presented to 8th Int. Hair-Science Symposium of the Deutsches Wollforschungsinstitut, Kiel, 1992.
30.
SwiftJ. A., The Detection of Pores and Holes in Hair by Electron Microscopy, “Hair Research for the Next Millennium,”Van NesteD. J. J.RandallV. A., Eds., Elsevier Science, NY, 1996.
31.
TateM. L.KamathY. K.RuetschS. B.WeigmannH.-D., Quantification and Prevention of Hair Damage, J. Soc. Cosmet. Chem.44, 347–371 (1993).
32.
VrentasJ. S.DudaJ. L., Diffusion, in “Encyclopedia of Polymer Science and Engineering,”vol. 5, J. Wiley & Sons, NY, 1985, pp. 36–68.
33.
WortmannF.-J., Der Einfluss von Wasser und niedrigen aliphatischen Alkoholen auf die rheologischen und feinstrukturellen Eigenschaften einzelner Lincolnwollfasern, Doctoral thesis, University of Technology, Aachen, Germany, 1981.
34.
WortmannF.-J.RigbyB. J.PhillipsD. G., Glass Transition Temperature of Wool as a Function of Regain, Textile Res. J.54, 6–8 (1984).
35.
WortmannF.-J., The Viscoelastic Properties of Wool and the Influence of Some Specific Plasticisers, Colloid Polym. Sci.265, 126–133 (1987).
36.
ZahnH., Wool is Not Keratin Only, in “Proc. 6th Int. Wool Text. Res. Conf., Pretoria,” addendum to vol. I, 1980.
37.
ZahnH.WortmannF.-J.WortmannG.HoffmannR., Wool, in “Ullmann's Encyclopedia of Industrial Chemistry,”vol. A28, VCH Verlagsgesellschaft, Weinheim, Germany, 1996, pp. 395–421.
