Naturally dyed wool

Mordanted, Natural-Dyed Wool and Silk Fabrics... 

The mordanting process had a profound effect on the shade and depth of shade of the natural-dyed wool and silk. This result was expected because the metal ions used in mordanting complex with the dye on the fiber (9). Copper, chromium, and iron mordants gave the greatest color changes. The morphology and chemical structure of the protein fiber also affect the nature of the interaction between the dye... 

Table V. Colorfastness of Naturally Dyed Wool to Laundering...

Table VIII. Color Measurement of Naturally Dyed Wool After Dry Cleaning Field Study (Plant A)...

Table X. Summary of Colorfastness Evaluation of Naturally Dyed Wool...

To ascertain if one of the above prohibited colours has been employed, the dyed wool is boiled for 5 minutes in a beaker with 50 c.c. of water rendered slightly alkaline with ammonia. The latter dissolves the colouring matter, the nature of this being then determined by means of the tests indicated in the table given by Possetto (next page). 

To gain a better understanding of the effect of protein fiber type, dye, and mordant on sunlight and burial weathering processes, we dyed wool and silk with three phenolic dyes (found as major components in natural dye mixtures extracted from various plant sources) and post-mordanted samples of the dyed fabrics with five representative metal salts. We then exposed the unmordanted and the dyed-mordanted samples to simulated sunlight or soil burial and measured the differences in the color and tensile properties that resulted from these treatments. 

Colorfastness of Wool Dyed with Natural Colorants. For the second series of experiments, wool samples were colored with natural colorants. Wool fabrics No. 526 were obtained from Test Fabrics, and natural colorants were supplied by Cerulean Blue. 

The two most important polyamide fibres are nylon 6.6 (171) and nylon 6 (172) whose structures are illustrated in Figure 7.10. A comparison with Figure 7.1 reveals the structural analogy between natural protein fibres such as wool and polyamide fibres. Polyamides may be dyed using acid... 

Analysis of dyed fibres allows identification of real colouring components of natural dyestuffs taking part in the dyeing process. Wool threads dyed with madder (Rubia tinc-torum) as well as Our Lady s bedstraw (Galium verum), were studied by HPLC DAD ESI MS" (SIM mode).[8] Chromatograms of the extracts from wool dyed with madder... 

It has been recognised for centuries that certain natural dyes, including alizarin, kermes, cochineal and fustic, now known to contain o-dihydroxy phenolic or anthraquinonoid residues in their structures, can be fixed on natural fibres using oxides or salts of transition metals as mordants. Although mordanted wool dyed with alizarin showed excellent fastness, reproducibility of shade was difficult to achieve because of the variable composition of the raw materials available. The famous Turkey red, in which alizarin was applied to aluminium-mordanted wool in the presence of calcium salts, formed a metallised complex the nature of which remains in considerable doubt. 

Cotton and wool, even non-mordanted, are dyed in a dye bath containing sodium sulphate dyed natural wool gives up its Substantive colour in a slightly alkaline medium to white cotton. . . colouring matters... 

Natural and mordanted wools are equally dyed in a bath containing sodium sulphate and acidified with acetic acid... 

Cotton mordanted with aluminium or chromium is not dyed, but that mordanted with tannin Is strongly dyed in the above bath dyed natural wool gives up its colour to tannin-mordanted cotton in a slightly alkaline medium. ... 

Mordanted cotton is dyed little or not at all dyed natural wool does not give up its colour to white cotton in a slightly alkaline medium, and on acidification takes up again the colour given to the... 

Natural wool is dyed in/ the above bath, but the I colour is only slightly resistant to soap mor-l danted wool is dyed1 more intensely and gives faster colours the colour varies with the mordant... 

Because natural silk, as a protein fiber of animal origin, resembles wool in its chemical structure, it can be dyed with most of the classes of dyes used for wool. The choice of dyes depends essentially on the fastness properties required. 

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