The moire fringes generated by overlapping two kinds of parallel straight line groups were applied to the stripe patterns. The image test was done by five stage evaluation method by the SD method based on the made stripe patterns, the evaluation of the stripe patterns were executed. As a result, the image of the monochrome stripe patterns clarified showing by three factors (the self-insistence, the ability, and the evaluation). In order to create the strong stripe patterns of self-assertion nature, it is good to choose what has narrow line width and overlapping up by the pitch ratio near an integer. It is good to use what has thick line width for creating the forcible stripe patterns. The regular stripe patterns had high evaluation. The evaluation that used the swinging theory as another evaluation method was done. The result of the monotonous patterns in which the created stripe patterns has regularity comparatively was obtained. Moreover, regularity was not found between inclination of the curve obtained from 1/f fluctuation theory, and the comprehensive evaluation obtained from the questionnaire.

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A curing method for hair straightening has been practically applied for decade. The straightening process consists of three step reactions: reduction followed by washing, heat treatment and oxidation. Two different reduction systems were used: one is a system containing thioglycolic acid (TGA) only and the other is a bicomponet system containing TGA and dithiodiglycolic acid (DTDG). Reaction mechanism was proposed on the basis of amino acid analysis of the hair samples obtained at various treatment steps. New equilibrium reactions were assumed to be established in the reduced fiber after washing and we could explain successfully the experimental results. As far as TGA is used for the reduction, a sever problem for the damage of hair arises from the formation of the mixed disulfide groups. There were important findings on this subject that (1) when the TGA-only system was used, the mixed disulfide groups were formed in the fiber and the amount of the groups incorporated was dependent on the concentration of TGA, (2) in the heat-treatment step at 180°C for 3 sec, the mixed disulfide groups were wholly converted into the thiol groups of cysteine residues, and (3) when the bicomponent system was applied, only the thiol groups were linked to the protein chains even under a hot permanent conditions at 45°C for 15 min. The role of DTDG is not only a reduction-regulating agent, but also a thiol-reforming agent, in other words, DTDG acts as an anti-damaging agent.

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Permanent waving and straightening hair treatments are important processes to set hair configuration for the maintenance of wanted hairstyle. There have been some unresolved problems related to hair damage arising from the use of thioglycolic acid as the reducing agent of hair. The most important one is the formation of carboxymethyl-3-alanyl disulfide (CMAD) groups, the so-called mixed disulfide groups, since the CMAD side chain groups on the protein backbone chains lead to a decrease of the number of disulfide cross-links in the treatment hairs and result in a considerable damage or lowering in the mechanical performance of the treated hairs. At present, we have no reliable quantitative analytical method for the CMAD groups formed in the hairs during permanent treatments. In this paper, it has been proposed that the content of the mixed disulfide groups could be estimated simply by using a High Pressure Differential Scanning Calorimetry (PDSC). The plots of the enthalpy of evolution of heat, ΔH_evol, evaluated from the exothermic peak area against the content of CMAD groups estimated by the calculation from the amino acid analytical data of the reduced hair samples showed a good linear relationship, which enables to an accurate measurement of the content of CMAD groups. Furthermore, the exothermal phenomenon observed on the PDSC curves for both permanent wave and straight hairs was considered to be closely related to hydrothermal reactions including an exothermic reaction of the side chain groups of sulfenic acid with the thiol groups of cysteine residues to form disulfide cross-links in hair. To elucidate the heat-induced reaction mechanism in the PDSC pans, CMAD wool keratin (CMADK) proteins with average molecular weight of 45,000 were synthesized as a model compound of the permanent treatment hair. The PDSC response of the CMADK proteins showed a similar pattern to those of the treated hairs suggesting the validity of our interpretation for the hydrothermal reactions in the hair.

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When various properties of nylon 6 fibers were investigated after microwave irradiation in organic solvents, it was found that both their hygroscopicity and dye ability for reactive dyes were improved largely because of a decrease in their crystallization. These properties were influenced by various conditions, such as the solvent temperature, microwave irradiation energy, and types of solvent. Compared with conventional methods, such as using an electric heater, microwave heating increased the solvent temperature more quickly and then enhanced the hygroscopicity of nylon 6 fibers more effectively, but their mechanical strength was decreased more dramatically under even low-temperature conditions. Direct heating of nylon 6 fibers containing microwave-absorbent organic solvents probably caused these unique phenomena.

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The effect of air function on discoloration behavior of oxidation dyes in wool fibers at ordinary temperature and humidity in dark room was investigated. The samples dyed under three different dyeing conditions and dyed with the different mixed ratios of precursor and copular were used in experiment. In the color change defined by chromaticity diagram (a^* and b^*) and color tone diagram (L^* and C^*), the color tone of samples dyed under dyeing system including alkali and hydrogen peroxide changed more significant than that of samples dyed in the performed oxidation dye solution. The discoloration of samples dyed with the different mixed rations of precursor and copular is scarcely dependent on mixed ratio, except for the couple system of p-diaminotoluene/p-amino-o-cresol. The modifications of physical and chemical structure of wool fibers had no effect on the decreasing rate of K/S value for the samples dyed using three precursor / copular systems.

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