To examine a repeatability of classification of size deviation and maximum deviation of the size test for raw silk, I take to computer simulation experiment of twice test for the same lot.
Difference of classification of size deviation are almost within 1 grade, but according to the ratio of variance of among skeins are enlarge, difference of 2 grade are appeared. Difference of classification of maximum deviation are more big, according to the ratio of variance of among skeins are enlarge, difference of 3 grade are barely appeared.
The ratio of differance of twice classification of size deviation are 0.25 to 0.50, and 1.38 times of the ratio of error in classification. The ratio of differance of twice classification of maximum deviation are 0.41 to 0.58, and 1.34 times of the ratio of error in classification.

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For the electronics testing of the raw silk size, we discussed the distribution characteristic of coefficients of variation of raw silk size. As we know, the size of the raw silk tested with electronic testing machine is a continuous sample. Due to the continuity of the size, the characteristics of the continuous size will be different from that of the random sample. In this paper we first gave the distribution of the coefficients of variation of the raw silk size of random testing, then deduces the distribution of coefficient of variation of continuous testing through introducing a equivalent model to random testing, which provides a theoretical basis for the development of electronic testing standard.

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The expression of 150 dai(300kama) in counting the number of reeling machines is incorrect.

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Demands of activated carbon for adsorbing several kinds of gas, which influenced human life, are increasing. In this study, high-performance activated carbons from cocoon, wasted cocoon and inner thin film were investigated. Carbonization of cocoon was performed by using an electric furnace in nitrogen atmosphere at 400°C to 1,000°C, or a micro wave oven for 1 min to 5 min. Observation of external surface and color of carbonized cocoon, SEM observation and yield were examined. Efficiencies of deodorant efficiency for ammonia and formaldehyde were measured. Adsorption retentivity of carbonized cocoon was calculated, and the values of adsorption retentivity for ammonia and formaldehyde were 67% and 23%, respectively.

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Cocoon carbon of maintained cocoon shape(bulky property) is used for several usage. Plate cocoon carbon from flat sheet cocoon(Gunma ×200) would be used for several application. Cocoon plates were prepared by hot-press method for several sheets of flat sheet cocoon. The largest values of bulkiness density and bending stress for cocoon plate were 1.26 g/cm³ and 55.9 MPa, respectively. Cocoon plate was dissolved in water at room temperature.
Several kinds of cocoon plate carbon were obtained from cocoon plate at 400°C∼1000°C, 1500°C, 1900°C in nitrogen atmosphere. Carbonization yield decreased with increasing carbonization temperature, and the value of it was 32% at 800°C. Crystalinity of cocoon plate carbon was classified into the hard carbon material by X-ray diffraction method.

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In order to develop new usage of cocoon, production of activated carbon from cocoon was examined. Cocoon plate was prepared by hot-press method for several sheets of flat sheet cocoon. Cocoon plate carbon was carbonized from cocoon plate under the condition of heating at N₂ atmosphere. In the purpose of improvement of deodorization for cocoon plate carbon, activation of cocoon plate carbon was performed by using water, CO₂-gas or chemicals (ZnCl₂, NaOH, K₂CO₃). Surface area of cocoon plate carbon was increased with using activation agents at 800°C. The largest value of surface area (2186 m²/g) was obtained in the case of K₂CO₃.

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New usage of cocoon was investigated for applying activated carbon. The largest specific surface area of activated cocoon plate carbon was obtained by a treatment with K₂CO₃ in the former paper. In order to obtain more large specific surface area, various condition of activation were examined. In this study, the largest value of specific surface area was 5571m²/g, which was obtained under the condition of heating at 800°C for 1h after immersed in an aqueous solution of K₂CO₃. Mean value of micro hole diameter was about 0.5 nm.

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Quality characteristics of raw silk were studied as per the International testing methods. Two varieties of raw silk viz., Indian bivoltine raw silk and Imported Chinese bivoltine raw silk were tested quality characteristics. The results indicate that the significant difference exists between the quality characteristics of the raw silk viz. size deviation, evenness variations I, winding breaks elongation and cohesion characteristics of raw silk. The study indicates that some scope exists in improving the quality of Indian bivoltine raw silk by adopting denier control gadgets in the field and process control measures.

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The purpose of this paper is to clarify the characteristics of Nagahama textile production area in the postwar and the condition of its existence in comparison with Tango textile production area. The method of research is studying from previous works and hearing from textile corparatives and two companies. The conclusion about charactaristics is as follows: the first conclusion is that the characteristics of Nagahama textile production area have been built with mono-production system (of “Thirimen”). The second is that production system has integrated from purchasing raw silk to finished crepe within each company completely. The conclusion about its existence is as follows: the condition of its existence are four, One is to get successor for inheritance of technology. Two is to maintain existing degum factory. Three is to reconsider the value of Weaving Industry. Four is to construct silk system.

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The purpose of this paper is to clarify the development of Debata in the postwar at Tango textile production area and the actual conditions of Debata. The method of research is studying from previous works and hearing from Tango textile corporatives and Debata. The conclusion is as follows: the first conclusion is that the development of Tango textile production area has been developed by two major departments, piece dyed and yarn dyed. The department of yarn dyed consisted of Debata that had been locally developed against the dominance of Oyabata in Nishijin, Kyoto. The second is that Debata has been under hard conditions from the view point of the work and the profitability. Also, it can be said that the relationship between Debata in Tango and Oyabata in Nishijin remains unchanged; the former is still subject to the latter.

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The effect of cocoon cooking condition on cocoon filament unwinding tension, reeling characteristics and quality of silk has been studied. Study has been conducted using five cooking conditions viz. single pan with three different temperatures, two pan cooking and pressurised cooking method. Results indicate that cocoon cooking condition influence the swelling and softening of sericin of cocoon filament layers and crossover points the cocoon shell and hence the agglutination force between the cocoon filament and cocoon shell. This in turn influences the reeling tension. Further, cocoon cooking conditions influence significantly the reeling characteristics and quality of raw silk. Results indicate that cocoon cooking conditions have significant correlation with reeling tension, reeling characteristics and quality of raw silk. From the results it can be inferred that under given reeling conditions, reeling tension will give an indications about the cocoon cooking condition, reeling characteristics and quality of raw silk and this could be utilized for process control in the filatures. From the results it is observed that two pan/pressurised cooking methods give significantly better reeling characteristics and quality of silk as compared with single pan cooking method.

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Silk user is interested in the characteristics of luster and color, but these characteristics have not been investigated. To breed a new characteristic silkworm race in cocoon filament, we researched about the luster and the color with raw silk and established an appraisal method. Four silkworm races, “Hakugin”, “Shin-Akebono”, “J137 × C146 (J*C)” and “Ariake” were used, and we enabled the measurement of the raw silk by winding it up to a plane bobbin. The luster values were measured in the parallel and the rectangular direction to the fiber. “Hakugin” showed high values in both directions. On the other hand, “J*C” was low. In the measurement of whiteness, “Hakugin” was high and “Shin-Akebono” was low value. Furthermore, negative correlation was recognized by size of cocoon filament and the luster/color though its degree was low, and the race of thin size showed the inclination of high values. To investigate the factor of these results, a cross section of the raw silk in each race was observed. The raw silk of Hakugin had smooth surface, and its inside was filled up enough by cocoon filament. These are regarded as the factor that luster value and whiteness level are high.

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The silk fibroin (SF) fiber from the Bombyx mori silkworm was treated with ultrasonic and salt-shrinking treatments, and its structure and physical properties were investigated to elucidate the effects of the two treatments.
In conclusion, the weight of the SF decreased after the ultrasonic treatment. The SEM images of the SF that underwent partial ultrasonic treatment showed fractures on the vertical surface and micropores on the cross section surface of the silk fibers. The tensile strength and elongation percentage of ultrasonically treated SF decreased considerably. The silk fiber crinkled and shrunk when the ultrasonically treated SF was treated with calcium salt, and many micropores appeared inside the SF. There were also changes in the aggregation structure; some of the molecule chains changed from a β-sheet structure to an unregulated structure after the salt-shrinking treatment.

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The silk fibroin (SF) fiber and the partially dissolved silk fibroin (PD SF) fiber from the Bombyx mori silkworm were treated with a rare earth (RE), lanthanum trichloride (LaCl₃) aqueous solution, and the structure and physical properties were investigated to elucidate the effects of the RE treatment. This study aims to find a new approach that can improve the natural shortcomings of silk fibers (e.g., poor shrink resistance) and to modify the silk fiber using a rare earth.

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The effects of argon-plasma treatment on the morphological and topographical surface structures of a Bombyx mori silk fibroin (SF) fiber were studied by using atomic force microscopy (AFM) and lateral modulation friction force microscopy (LM-FFM). Surface changes were analyzed in image and in quantity for different plasma treatment times. The AFM and LM-FFM analyses showed that the roughness of the fiber surface increased after plasma treatment because of plasma bombardment and etching. A longer treatment time, resulting in a rougher surface, progressively changed the fiber surface, thereby leading to the formation of a new surface. These results revealed that low-temperature argon-plasma treatment is an effective method to improve the performance of SF fibers.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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In this paper, we studied the morphology, aggregation structure and mechanical properties of partially dissolved silk fibers modified with lanthanum trichloride (LaCL3) to find a new approach to improve natural shortcomings of silk fibers, including poor shrink resistance.

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[in Japanese]

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