• International Journal of Industrial Entomology and Biomaterials
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• v.21 no.1
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• pp.145-150
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• 2010

The regenerated silk fibroin with various molecular weights (MW) was prepared by different dissolution condition and the effect of coagulant on the wet spinnability of the various MW silk fibroin solutions dissolved in formic acid was investigated by the observation of wet spun filament in coagulant and the measurement of maximum draw ratio. The observation on the wet spun filament in coagulation bath revealed that good fibers without bead were formed in a high MW and a very high MW silk fibroin samples. In contrast, beads were observed in the silk fibroin sample with medium MW. The maximum draw ratio of wet spun silk fibroin filament decreased with MW reduction. The decrease of maximum draw ratio in isopropanol, acetone, DMF and THF was remarkably higher than that in methanol and ethanol, indicating that the coagulant type strongly influenced the wet spinnability. The two simple evaluation methods used in this study showed complementary information for wet spinnability: (a) The observation of filament in coagulant was effective to check a continuous fiber formation and a bead formation, and (b) the maximum draw ratio measurement was useful to examine the post drawing ability related to molecular orientation.

• Proceedings of the Korean Fiber Society Conference
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• 2007.11a
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• pp.101-104
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• 2007

• Textile Coloration and Finishing
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• v.5 no.2
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• pp.99-108
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• 1993

In one dyeing system of silk/synthetic blend fabrics (polyester, nylon, acetate) with acid dyes/disperse dyes, dyeability and desorptibility of disperse dyes on silk fabric and transfer from dyed silk fabrics to synthetic fabrics by color difference were examined. When silk dyed with C.I. Disperse Red 19 and C.I. Disperse Red 60 at 10$0^{\circ}C$ for 60 minutes, color difference of dyed silk were $\Delta$E=56.72, $\Delta$E=47.65 for blank silk, respectively. The desorption rate of the dyed silks were measured in boiling bath with and without dye-free synthetic fibers. The desorption rate of dyed silk was effected by affinity of synthetic fabrics contained. When silk dyed with Red 19 and Red 60 was reduced at 10$0^{\circ}C$ for 60 minutes, the decolouration rates of dyed silk were 75% and 40%, respecdtively.

• Journal of Sericultural and Entomological Science
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• v.36 no.2
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• pp.138-146
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• 1994

The structural characteristics of Antheraea yamamai and Antheraea pernyi silk were investigated by using x-ray diffraction method, IR spectroscopy and polarizing microscopy. The amino acid composition, fiber density, thermal decomposition temperature and glass transition temperature were also measured for relating these physical properties to the structure in comparison with those of Bombyx mori silk fiber. There was no significant structural difference between A. yamamai and A. pernyi silk fiber on an examination of x-ray diffraction curve and IR spectrum. Both of these wild silk fibers showed double diffraction peaks at the Bragg angle 2Θ16.7˚ and 20.5˚by x-ray diffraction analysis as well as IR absorption peaks for the bending vibration of specific groups related to ala-ala amino acid sequence. On the other hand, the x-ray diffraction curve and IR spectrum of Bombyx mori silk fiber are different from those of wild silk fibers, indicating different crystal structure as well as amino acid sequences. It showed under the polarizing microscope examination that the birefringence and optical orientation factor of wild silk fibers are much lower than those of B. mori silk. Also, the surface of degummed wild silk fibers was characterized by the longitudinal stripes of microfibrils in the direction of fiber axies. The amino acid composition, which is strongly related to the fine structure and properties, was not significantly different between these two wild silk fibers. However, the alanine content was somewhat less and polar amino acid content more for A. yamamai. As a result of fiber density measurement, the specific gravities of B. mori, A. pernyi and A. yamamai were 1.355~1.356, 1.308~1.311, 1.265~1.301g/㎤ in the order, respectively. The calculated crystallinity(%) was 64% for B. mori and 51~52% for wild silk fibers, which showed same trend by IR method in spite of somewhat higher value. The thermal decomposition behaviour was examined by DSC and TGA, showing that the degradation temperature was in the order of B mori, A. prernyi and A. yamamai at around 350$^{\circ}C$. It was also observed by TGA that the decomposition seems to proceed step by step according to their specific regions in the fiber structure, resulting the difference in their thermal stabilities. The glass transition temperature was turned out to be 220$^{\circ}C$ for B. mori, 240$^{\circ}C$ A. yamamai and 255$^{\circ}C$ A. pernyi by the dynamic mechanical analysis. It is expected that the chemical properties are affected by the dynamic mechanical behavior in accordance with their structural characters.

• The Korean Journal of Community Living Science
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• v.27 no.4
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• pp.795-801
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• 2016

This study was conducted to suggest the best union fabric to combine with cellulose fiber for summer and in-between seasons. Four types of union fabric, viz. silk/flax, silk/cotton, rayon/flax and rayon/cotton, were used as sample fabrics after weaving them in a local textile factory. The air permeability, moisture regain, water absorption, water vapor permeability and thermal insulation of the samples were tested. The results are as follows. The rayon/flax union fabric is the most suitable for summer clothes due to its having the best comfort property of air and water vapor permeability, and moisture and water absorption. For in-between seasons, it is recommended to use the silk/cotton union fabric because of its good thermal insulation properties.

• Proceedings of the Korean Fiber Society Conference
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• 1996.10a
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• pp.507-512
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• 1996

To study Antimicrobial activities of wool and silk dyed by Impatiens balsamina extract with concentraion and times of dyeing, its leaf and stem was extracted by water. Wool and silk dyed by extracts were their microbial inhibition activities against Staphylococcus aureus KCTC 1928. The more concentration, The more times of dyeing their microbial inhibition activities were increased. Fabrics dyed by leaf estracts were higher microbial inhibition activities than fabrics dyed by stem extracts. Silk dyed by the leaf and stem extracts were higher microbial inhibition activities than wool dyed by the leaf and stem extracts. the more dye uptake, microbial inhibition activities of dyed fabrics were incresed.

• Textile Coloration and Finishing
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• v.19 no.5
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• pp.8-16
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• 2007

The dye-resist effect of reactive dye-resist agents in reactive dyeing of silk was investigated. The dichlorotriazine-based dye-resists achieved a higher effectiveness than others since they make a charge barrier of diffusion in the silk fiber periphery due to high reactivity of dichlorotriazine group. Similarly, in the case of hetero-multifunctional dye-resist agent, the dye-resist agent containing both a dichlorotriazine and an ${\alpha}$-bromoacrylamide reactive groups achieved better resist effectiveness than those containing both a monochlorotriazine and an ${\alpha}$-bromoacrylamide groups. Also, their resist effectiveness was improved by increasing the number of sulfonate groups in the dye-resist agents and the number of reactive groups in the reactive dyes applied to them.

• Journal of Sericultural and Entomological Science
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• v.18 no.1
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• pp.21-26
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• 1976

The study was carried out to investigate the variations in the fibroin hydrolysis of different cocoon shell layers, and the relationship between the hydrolysis and silk physical property. The obtained results are as follows: 1. The fibroin hydrolyzing ratio was highest at the inner layer of cocoon shell and. next in order. at the middle layer and at the outer layer. 2. The fibroin hydrolyzing ratio of abnormal cocoons was higher than normal cocoon and it was different among them, tile highest was double coroon, thin shell cocoon and perforated cocoon in order. 3. The sericin content and fibroin hydrolyzing ratio of Jam 111 and Jam 112 was higher than that of Jam 111 $\times$ Jam 112. 4. The fibroin hydroiyzing ratio of the cocoons fed with the artificial diets was increased at the inner layer. The sericin content of those lessened at the inner layer, however, it slightly increased at the most inner layer more than at the inner layer. 5. The breaking strength of the degummed silk fiber of different cocoon layers was reduced at the inner layer. The breaking Strength of abnormal silk fiber was less than that of normal silk fiber. 6. A negative correlation (r= －0.8) )was approved between fibroin hydrolyzing ratio and breaking strength of silk fiber, and the regression line was Y=－0.29x＋5.07.

• Journal of the Korean Dietetic Association
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• v.8 no.2
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• pp.175-184
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• 2002

This study is to investigate consequent nutrient intake status, influence of body mass index(BMI), and fat distribution on the silk amino peptide(SAP) and dietary fiber supplementation. During 2 months of this research (January to March, 2002), 45 women aged 20yr – 30yr (average age 24.6yr) were selected as subjects. Nutrient intake was investigated by questionnaire, 24-hr recall method. Antropometric assessments of the subjects were investigated by SBIA method(Segmental bioimpedance assay, In body 3.0). The results are as follows: mean body weight 57.7kg, mean body height 161.9cm mean BMI 22.0, and mean food habit score was 8.47. Defecation frequency was increased by dietary fiber supplementation. Frequency of pain during defecation was significantly decreased by dietary fiber supplementation (p<0.01). Feeling of residual feces was significantly improved by dietary fiber supplementation(p<0.001). Status of energy and carbohydrate intakes significantly decreased after dietary fiber supplementation(P<0.05). Body fat and WHR(waist hip ratio) significantly decreased after dietary fiber supplementation(P<0.001), and percent body fat was decreased by dietary fiber supplementation, significantly(P<0.05). Above results of this study show that dietary fiber-added routine diet improves defecation condition, and lessens body fat, percent body fat without losing body muscle. Especially, declination of abdominal fat and WHR were notable. That meant decreased risk factor.

• Proceedings of the Korean Fiber Society Conference
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• 1999.10a
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• pp.407-410
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• 1999