Silk fibroin cast film was prepared using a ternary solvent system of CaCl₂/CH₃CH₂OH/H2O (1/2/8 in mole ratio). A drying temperature at casting influenced crysta1 structure of fibroin. When a drying temperature was set at 4 centigrade, the cast film became amorphous. When a drying temperature was set higher than 60 centigrade, a fibroin film of silk-II crystal was obtained. A fibroin film of silk-I crystal was obtained in the temperature range from 10 to 50 centigrade. Also, silk-I crystal was generated from random coil through exposure of an amorphous film to water vapor at 20 centigrade. As for the crysta1 transformation from silk-I into silk-II, the treatment with a glycerol solution was effective. In the course of the treatment a film showed self-thinning and self-expanding. The expansion ratio exceeded 30 % at maximum. The film produced accompanying self-expansion was ductile in nature. L929 cells were cultivated in MEMAM containing extracts from silk fibroin films. The extracts did not inhibit the multiplication of L929 cells.

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We made reports on the characteristics of Japanese and Chinese regional silkwomiraces in the previous papers. In this papaer, the many quantitative characteristics of European silkworm races were analyzed. There are 46 of the European silkworm races (they are regional silkworm races) maintained as the genetic resources at National lnstitute of Agrobiological Sciences, Japan. The quantitative characteristics of European races have been clarified by the correlation analyses among many cocoon qualities. These characteristics were condensed into a few over all characteristics by ‘MaltivariateAnaiysis’. Futher, the correlations between the overall characteristics and quantitative characteristics were clarified. In conclusion, we examined the quantitative characteristics of the European silkworm races by the interpretation of the overall characteristics from the viewpoint of filature.

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The current situation of Japanese fiber industry is becoming severe more and more. Because Import textiles and fabrics increase rapidly, the purchasing action of consumers has changed. Therefore the fiber industry is in recession for a long time and the total scale of the industry is reducing more and more. Additionally, the production of silk textiles and fabrics is in the sarne trend now. The purpose of this paper is to clarify the postwar development and the strategy of the Fujiyoshida textile production area. The method is based on the hearing at Fujiyoshida textile cooperative association etc. The conclusion is as follows: The postwar development in the Fujiyoshida production area is divided into four stages. The first period is the backing fabric production. The second is the bedding and the Kimono fabric. The third is the necktie fabric. The fourth is the various and small-lot fabrics. The characteristics of production and marketing structure on the recent year are as follows: The first is the deduction of allied companies, especially in textile manufactures. The second is small-sized textile manufactures. The third is three channels of marketing. Main channel is OEM (Original Equipment Manufacture), Subsidiary channels are the direct marketing and the direct sale for tourists. Therefore under the difficult circumstarices, the way of the various and small-lot production has developed. The strategies are as follows: The strengthening of the cooperation between allied companies. The development of the silk goods to tourist.

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Le cocon est vivant. Puisque, Le conservation n'est pas possible peridant la long terme. Donc, Le probleme de grande est le technique de conservation.Quel technique pratiquent — les anciens? Il y a la mention de la technique de plusieurs espéce dans le document historique de la Chine (A.D. 12 C). J'ai vérifié la légende de tuchinique de la pratique. et, Les essais comparatif de leur caracteristiques physique du fil. A Expérience, Il en résulte que le conservation du cocon sur le classiques de technique était a mesure efficace. La technique de la salaison et la technique qui enfume un cocon, la dessiocation de la étuve et le cocon de vapeur sont le bon ptocédé. La techniquc qui séche cocon au so1ed ne 1ui va pas pourle long terme.La salaison du fil plus élastique que le coeon sec du so1ei1. La salaison du M plus dur que le cocon sec du soleil. Il y était la force d'un fil dans la salaison du fil. La prepriété desyoung's modulus aussi.surtout, La technique de la salaison s'est avéré efficace .mais, Si on ne peut pas hérmedque le cocon hennédquenient Il n y a pas de effet de insecnicide. Le coeon de vapeur estjaunis avec le terrrps.

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Climate Change and Global Warming affect human life in many ways. So, we have to know heat conducting characteristics of fabrics in hot or cold environment and find some measures to spend comfortably in hot and cold seasons. We studied thermal conductivities of various fabrics (Yamada 1997) and obtained knowledge on why silk is cool(Yamada and Naruse 2002).
In the present study, thermal conductivities are measured in the atmosphere of several temperatures and humidities. And it was found thermal conductivity of fabrics is determined by the volume fractions and the thermal conductivities of air, water and fibers.
Main part of heat is transfered through fibers and for this part of the thermal conductivity the result showed that the effect of the volume fraction of fibers was grater than the effect of temperature.

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The two varieties of cocoons viz., multi-bivoltine crossbreed cocoons (PM × NB4D2 race) and bivoltine hybrid cocoons (CSR2 × CSR4 race) reared during the sarne season were studied for the reeling performance and quality characteristics. The results indicate that the cocoon races have significant influence on the cocoon characteristics viz. Cocoon weight, shell weight, shell ratio percentage, average filament length, non-breakable filarnent length, single cocoon filament denier, on the reeling characteristics, viz. reelability, renditta, raw silk percentage, raw silk recovery percentage, waste generated during reeling and pelade weight and on quality characteristics, viz. neatness, cleanness, tenacity, elongation, cohesion, degumming loss characteristics of raw silk.

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The influence of cocoon cooking condition and croissure length on certain quality characteristics of raw silk has been studied for Indian bivoltine hybrid cocoons. Study has been carried out using two cooking methods viz., single pan and pressurised and three levels of croissure length - 3 cm, 8 cm and 13 cm. Results indicate that both cocoon cooking condition and croissure length have significant influence on quality of silk. As the croissure length increases, tenacity, cleanness and cohesion of raw silk are found to increase significantly. Single pan cooking and shorter croissure length of 3cm affect the quality of raw silk significantly. The quality characteristics of raw silk viz., neatness, cleanness, tenacity, elongation and cohesion have been found to be significantly better in the case of pressurised cooking and 8 and 13 cms croissure length. It is observed that cocoon cooking condition plays a more dominant role as compared to croissure length on cohesion of raw silk Results indicate that cooking the cocoons to the required level and maintaining the good croissure length of 8 to 13 cm are essential for producing better quality silk.

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For evaluation of the emulsifying ability of sericin extracted directly from fresh cocoons of Bombyx mori,are producible method has been formulated for preparing a vitamin E (α-tocopherol) emulsion through mechanical agitation using a high-speed homogenizer. The emulsifying ability varied depending on the timing of vitamin E addition, decreasing significantly when vitamin E was added prior to agitation in comparison with that when added along with agitation. It was shown that sericin effectively emulsified vitamin E when mixed in a sericin/vitamin E ratio of about 1 to 5 in weight. The concentration of phosphate buffer solution did not affect the emulsifying ability of sericin. Emulsions, however, were labile in solutions containing 3mM or higher sodium phosphate buffer (pH7.3), showing some insoluble sericin material after standing quiescent for 24h.

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The effect of difference in temperature between high temperature steam treatment and low temperature water permeation treatment and duration of high temperature steam treatment of cocoon cooking on reeling performance and quality characteristics of raw silk has been studied using Indian CSR race bivoltine hybrid cocoons. It is observed that both difference in temperature between high temperature stearn treatment and low temperature water permeation treatment and duration of high temperature steam treatment have a significant influence on reelability, filarnent length, non-broken filarnent length, raw silk%, neatness, cleanness, tenacity, elongation and cohesion of raw silk. Results indicate that 10°C ∼15°C difference in temperature between high temperature stearn treatment and low temperature water permeation treatment with 90∼93°C temperature and 1.5 to 2.0 min duration at high temperature stearn treatment zone of cocoon cooking give better reeling performance and quality raw silk from CSR race bivoltine hybrid cocoons.

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