Hair fibres

When wool or hair fibres are stretched in a solution of sodium hydroxide, and the tension is released whilst they are still immersed, they will relax to... 

Wool and hair fibres can be taken from a wide range of animal species such as sheep, goats, camels, yak, musk ox, llamas and related species, and fur animals (rabbits, foxes, beavers and the like), among others. The properties of these fibres are dictated by the source, and these variations can influence length, diameter and fineness, mechanical characteristics and durability, colour and dyeability. 

Hair fibre Ring/core Cuticle Cortex... 

Nearly all hair care products incorporate one or more cationic conditioning agents, where the latter can be either cationic surfactants or cationic polymers. The cationic surfactants can be further divided into four major classes, i.e. alkylamines, ethoxylated amines, alkyl imidazolines, and quaternaries. The quaternaries are the most widely used in the personal care industry because of their strong affinity to the hair fibre surface. 

Hearle, J.W.S. (2000) A critical review of the structural mechanics of wool and hair fibres. Int. J. Biol. Macromot.,21 123-128. 

Six 180 gsm fabrics were selected, comprising a variety of exotic animal hair fibres (mohair, alpaca and cashmere) and Sea Island cotton as weft yarns and silk or polyester warps ... 

Semi-permanent dyes are usually applied to natural, unbleached hair after shampooing. The formulations use mixtures of dyes, blended to the desired shade. It is common to use several dyes of similar colour but with different molecular sizes to provide even coloration. Larger dye molecules tend to be retained by the more damaged tip of the hair, but do not penetrate so readily into the roots, while smaller molecules penetrate the entire hair fibre but wash out of the more porous tip. 

Nagorcka, B.N., Mooney, J.R. (1982). The role of a reaction-diffusion system in the formation of hair fibres. Journal of Theoretical Biology, Vol.98, pp. 575-607. 

Nagorcka, B. N. Mooney, J. R. 1982. The Role of a Reaction-Diffusion System in the Formation of Hair Fibres, J. Theor. Biol. 98, 575-607. 

Human hair is mainly composed of fibrous a-keratin proteins. Hair fibres are not continuous in their full length, but rather result from compact groups of cells within the fibre follicle, from which three farther basic morphological components of hair structure originate the multicellular cuticle sheath, the fibrous cortex and the medulla [1, 2],... 

Vacuolated cells may also be present along the axis of coarser a-keratin fibres, forming the medulla. These cells generally constitute only a small percentage of the mass of hair and are believed to contribute negligibly to the mechanical properties of human hair fibres. Physically, the medulla forms the empty space of the fibre [4, 7],... 

Studies on protein-based formulations to treat hair fibres have also been widely explored. Several patents disclose compositions capable of restoring hair health by providing excellent finishing effects. Applications of proteins such as a water-soluble compound derived from a vegetable protein derivate [170], non-naturally occurring keratin proteins [171], a mixture of a hydrolyzed protein and an amino acid with an aliphatic side chain [172], and other hydrolyzed proteins [173, 174] are also examples within this category. 

PDI has also been used for treatment of wool [179] and hair fibres [180]. King and Brockway [179] showed that PDI was able to restore part of the original properties on aged or harshly treated wool. The same enzyme was used by Brockway [180] to perform a curling, waving or straightening treatment safely under mild condition. 

Wool and hair fibres consist mainly of keratin, which consists of polypetide chains bound by salt Unkages between the functional groups of the amino acids (4.127) and by cystine (S—S) linkages (4.128) ... 

Morel, O. Christie, R. M. Greaves, A. Morgan, K. M. Enhanced model for the diffiisivity of a dye molecule into human hair fibre based on molecular modeling techniques. Color. Technol. 2008, 124, 301-309. 

Mortmami, The Structure and Properties of Wool and Hair Fibres , in Handbook of Textile Fibre Structure, Volume II Natural, Regenerated, Inorganic and Specialist Fibres, editors Eichhom, S.J., Hearle, J.W.S., JafFe, M., and Kikutani, T., Woodhead Publishing Limited, 2009. 

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