To understand the cross-linked structure of hair and wool keratin fibers, rubber elasticity theory was used to model the force-extension curve of swollen fiber in a diluent mixture of concentrated aqueous lithium bromide solution and pure diethylene glycol mono-n-butyl ether. A two-phase structural model was assumed for the globular matrix keratin-associated protein (KAP) dispersed in the swollen network of intermediate filament (IF) proteins. Structural parameters were obtained by fitting force-extension curves to theoretically derived relations between elastic forces originating from nonuniform network and extension ratios. The parameters extracted are the number of intermolecular SS bonds in IF, the volume fraction of matrix proteins in the fiber, and the shape of the matrix domain. The number, type, and location of SS cross-linkages on an IF protein chain were estimated using the results obtained in the reactivity of SS bonds of wool and hair fibers in boiling water and also in the behavior of SS bonds in permanent waving treatment of hair. Boiling water data were mainly based on the reactivity of SS bonds in self-cross-linking reactions forming stable lanthionine and lysinoalanine cross-links, and the data for the permanent wave hair were based on the scission mechanism in reduction with thioglycolic acid and subsequent reformation of the SS bonds during oxidation. A near-perfect reformation of the SS bonds in the IF molecules were attained in the latter, but the reformability of the bonds between the KAP molecules was very low. To assess the cross-linked structure of KAP component proteins, permanent wave hairs were used and the results analyzed were presented for the verification of this model. The total amount of SS cross-links is twenty-one moles on an IF chain of average molecular mass of 50000. Out of the twenty-one moles, thirteen moles are intermolecular cross-linkages and eight moles are intramolecular cross-linkages. A KAP molecule with an assumed molecular mass of 20000 involves seventeen moles of intramolecular SS bonds and four to five sites on the surface of the KAP molecule of hair keratin. These sites link to adjacent KAP molecules and form an aggregate of about six KAP molecules against an IF molecule in the hair, while in the wool, about three KAP molecules with thirteen moles of intramolecular bonds aggregate against the IF molecule. It was found that there is a considerable difference in the KAP structure between hair and wool. A network model of the IF-KAP structural unit in the hair and wool fiber cortex was thus proposed. It was inferred that the extension modulus of hair fibers in water may be controlled by compressional forces exerted from the elastic network of KAP molecules around the IF.

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It has been known that natural source of origin peroxidases, such as rice hull peroxidase (RPO), horseradish peroxidase (HRP), soybean peroxidase (SPO), and Arthromyces ramosus peroxidase (ARP), might be alternative candidates for bleaching system. However, their characteristics have not fully investigated. The purpose of this work is to evaluate these peroxidases for the decoloration of Orange II with high concentration of H₂O₂. Consequently, RPO system showed high decoloration rate contents even at the high concentration of H₂O₂, 150 mM, comparing with other PODs. Furthermore, decoloration activity of this RPO was stable under the coexistence of H₂O₂ at 120 minutes. By assessing PODs oxidation states at the high concentration of H₂O₂, 75 mM, intermediates, namely Compound III and Compound IV, appeared to be formed in the RPO and HRP oxidation cycle, and inactivated the decoloration reaction. Interestingly, only RPO system could maintain decoloration rate contents after several reaction cycles. In conclusion, RPO might be effective to edge closer to practical use as washing enzyme.

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The microwave heating fixation method for textile printing was developed, where printed fabrics are irradiated through waveguide slit and heated. The dye fixation ratio obtained by microwave heating fixation method was estimated in terms of microwave power, microwave heating time, temperature of fabric surface, water regain for the pre-treated cotton fabric, and urea concentration of pre-treating agent. The dye fixation ratio of the microwave heating fixation method was higher than that of the conventionally-dry heat treatment. To get an enough dye fixation ratio, the microwave power for the microwave heating fixation method was generally 500 W, and water regain for the pre-treated cotton fabric was about over 21.3 wt%. The microwave heating time for the microwave heating fixation method was 20-80 sec by adjusting the urea concentration of pre-treating agent to 13.9-9.0 wt%. The temperature of fabric surface in microwave heating treatment was over 100 ℃ when it got high dye fixation ratio, and was the reaction initiation temperature of monochlorotriazine-based reactive dye. The urea concentration of pre-treating agent was contributed to increase dye fixation ratio and temperature of fabric surface in microwave heating fixation process. The results show that the microwave heating fixation method is a powerful technique for the dye fixation of reactive dyes by the printing method.

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he mechanical properties of carbon fiber reinforced plastic (CFRP) is strongly dependent on the mechanical characteristics and the arrangement of the carbon fiber monofilaments which consist of multifilament. In the case of the fibers for clothing, the weaving performance of the thread which put on the twist is improved in comparison with the case of the yarn without twist. On the other hand, elastic modulus and fracture strength of carbon fiber are strongly influenced by applying twist to the multifilament. However, the relationship between the fracture behavior and twist number applied to the multifilament has not been perfectly clarified. In this study, the fracture stress distribution is evaluated by tensile test of carbon fiber monofilaments. Furthermore, by using these results, the effect of twist number on tensile properties of the twisted carbon fiber multifilament is evaluated by carrying out the numerical simulation of dynamic model and compared with the experimental results.

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