• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.169-175
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• 1998

The morphology of silk fibroin/poly(vinyl alcohol)(PVA)blend films was investigated using optical microscopy and confocal laser scanning microscopy. The effects of blend ratio and molecular weight of silk fibroin and PVA on phase separation were studied. Macro-phase separation occurred for the silk fibroin-rich/poor region whereas micro-phase separation took place for the dispersed/continuous phase, In spite of differences in molecular weight and blend ratio, it is observed that the dispersed phase and continuous one are composed of silk fibroin and PVA component, respectively. As the molecular weight of silk fibroin and silk fibroin content in blend ratio are decreased, the compatibility of blend is increased due to the reduction of micro-phase separation.

• International Journal of Industrial Entomology and Biomaterials
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• v.28 no.1
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• pp.19-24
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• 2014

Silk has always been one of the most favored textile materials. Fully degummed silk fiber (i.e., silk fibers without sericin) shows better luster than raw silk fiber (with sericin); it is also softer. On the other hand, raw silk fiber feels cooler because of the presence of sericin, making it useful as a textile for the summer season. Recently, partially degummed silk has attracted researchers' attention because it provides better luster, feel, and dyeing properties. However, the partial degumming of silk is very difficult because it results in inhomogeneously degummed fiber. In the present study, silk yarns were degummed with surfactant aqueous solutions and the effects of each surfactant on the degumming ratio, crystallinity, and homogeneity of the degummed silk yarn were examined. The degumming ratio and crystallinity index of silk yarn varied depending on the type of surfactant. On the whole, anionic surfactants resulted in higher degumming ratios and better homogeneity than nonionic surfactants.

• Journal of Fashion Business
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• v.10 no.3
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• pp.78-86
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• 2006

Coffee extract dyeing on silk fabric using various mordanting agents at different mordanting condition was studied in our previous research. Coffee extract dyeing can exert beautiful colors and have several advantages over the conventional natural dyeing. Since most of natural dyes are expensive for mass production, strongly season and source dependent, and hard to store, and therefore, coffee waste was used as natural dye to create beautiful colors in this study. Coffee waste is inexpensive and easy to store, and provide a comparatively regular quality regardless of season and source. The effects of dyeing condition such as dyeing temperature, dyeing time, and liquor ratio on dyeing characteristics of silk fabrics were investigated. Coffee extract dyed silk showed brilliant colors, and the colors were different with the kind of mordant. Cu, Sn, and Al mordanted silks showed golden yellow with subtle change of hue and value, while Fe mordanted silk showed a brownish green color upon coffee extract dyeing. As the dyeing temperature increased, the dyeability generally increased in all mordanted silk fabrics except Fe mordanted silk until $45^{\circ}C$. The dyeing temperature did not affect the dyeability of Fe mordanted silk fabric. As the liquor ratio increased, the dyeability showed a gradual increase in all mordanted silk except Cu mordanted silk. Cu mordanted silk fabric showed an abrupt increase in dyeability at liquor ratio1:150. The dyeing time effect can be separated into 2 stages. During the initial half an hour, the dyeability did not change significantly, and then, increased after 45 min. dyeing time duration. A further increase in dyeing time after 45 min. did not affect the dyeing efficiency in all mordanted silk fabrics except the Cu mordanted.

• 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.

• Journal of the Korean Society of Costume
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• v.54 no.8
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• pp.113-128
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• 2004

This study examined textiles used for ancient costumes of the $16{\cdot}17th$ century in Joseon period, focusing on fabric types and patterns of the costumes from tombs. The purpose of this study was focused on investigating the relationship between fabrics and social backgrounds, especially change in using fabrics through the war from Hidyoshi's Invasion of Korea in 1592. Since the war must have had an effect on the life of people's. The result of the study is that silk occupies $69{\%}$ of all textiles, and cotton, linen follow The weaving method of silk was primarily Plain and satin weaves. However the use of twill, gauze, and double weave, that had led weaving methods of silk during the Koryo Period, were considerably decreased in Joseon Period. Types excavated fabrics in the $16{\cdot}17th$ century Joseon period can be said various. Of this, silk was the most remarkable one till Hidyoshi's Invasion of Korea in 1592, when the ratio of patterned silk dramatically decreased. Contrarily, the ratio of cotton and plain fabric increased rapidly in Hidyoshi's Invasion of Korea in 1592. It is supposed that the result is largely due to unusual condition of the war time. After the war, it is estimated that use of pattened fabric as well as silk was decreased. Patterns of textile fabrics in $16{\cdot}17th$ century were various. In result of surveying a trend of increment and decrement, it is known that the ratio of patterned textile fabrics decreased dramatically in Hidyoshi's Invasion of Korea in 1592 and Manchu war of 1636. Tendency of textile use by social Position is more notable. It is appeared that a lot of silk fabrics were used in High hierarchy. The excavated remain and ratio of silk were the highest in Kyonggi Province including Seoul.

• International Journal of Industrial Entomology and Biomaterials
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• v.19 no.2
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• pp.265-268
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• 2009

Wild silkmoths can be utilised sustainably in the production of silk as an income for resource-poor rural communities. However, attack by parasitoids and predators affect the quality of cocoons and quantity of raw silk produced. A laboratory experiment was undertaken to quantify the effect of parasitoids' (dipteran and hymenopteran) and predators' (ants) exit and ingress holes, respectively, on silk production. The mean number of shells required to produce fifty grams of raw silk was highest with cocoons parasitised by a dipteran and lowest with unattacked cocoons (but with moths already emerged). Degumming loss was highest in parasitised and lowest in unttacked cocoons, but both were not different from cocoons predated by ants. Shell weight was highest in unattacked cocoons, followed by hymenopteran-parasitised and predated cocoons, with the dipteran parasitized ones being the least. Single cocoon weight was greater in hymenopteran-parasitised and predated cocoons than the dipteran-parasitised and unattacked cocoons. Shell ratio or raw silk, floss and yarn weights were higher in unattacked than parasitised and predated cocoons. The total loss in raw silk attributable to attack by parasitoids and predators ranged between 17.4~31.2%. The results offer baseline information for assessment of economic losses in wild silk farming due to parasitoids and predators in the field.

• International Journal of Industrial Entomology and Biomaterials
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• v.13 no.1
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• pp.45-50
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• 2006

Papers were prepared from cut cocoons and mulberry branches, which are byproducts from sericulture industry. The long filament of silk should be cut into appropriate length in order to prepare paper and this was achieved by chemical method. By a mixture of sodium hydroxide and sodium carbonate solution, the silk filaments were cut into short fibers (less than 1 mm in length). Since the short silk fibers (sSf) could not bind each other by itself, starch and poly(ethylene oxide)(PEO) were added as a bonding agent. When starch and PEO were used in a ratio of 3:7, the silk papers had optimum mechanical properties for paper. Fibers from the skin of mulberry branches (MBF) were added to sSf to enhance the mechanical properties of pure silk paper. Bleaching of MBF was performed with a mixture of hydrogen peroxide and sodium silicate. The mechanical properties were greatly enhanced and the optimum blend ratio of MBF and sSf were 7:3. The mulberry/silk paper has good absorption property against formaldehyde, and therefore, the paper could be applied as a wall paper for preventing the sick house syndrome.

• Journal of Sericultural and Entomological Science
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• v.3
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• pp.33-36
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• 1963

This experimental work is aimed to find that there is any industrial potentiality of tussah silk reeling service. The obtained results are as follows. (1) The physical nature of tussah cocoon and its silk was investigated as prelim. (2) The best silk and chemical reeling ratio of tussah cocoon was obtained in case of using 3,000 time diluted NaOH during one hour boiling process. (3) The reeling efficiency of dupion type silk (37.5g/hr) was found as a better process than that of the normal type of silk (10g/hr). (4) It is believed that there is still possibility to increase the silk reeling ratio of tussah cocoon and to industrialize the tussah silk reeling in case of processing as dupion type silk.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.55-55
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• 2012

To improve the deodorizing and antibacterial performance of various fabrics (cotton, silk and wool) dyed with pomegranate(Punica granatum L.) extract without mordants, natural colorant solutions, which were extracted from pomegranate using water as an extractant at $90^{\circ}C$ for 90 min with a various liquor ratio (solid natural colorant material/solvent water, weight ratio) from 1:100 to 1:5 were used. To achieve the highest K/S and the deodorizing and antibacterial performance, the best liquor ratio, dyeing bath ratio, dyeing temperature and dyeing time were found to be 1:10, 1:50, $80^{\circ}C$ and 60 min, respectively. The deodorizing performance of dyed cotton, silk and wool fabrics against acetic acid vapor were found to be95,70,90%,respectively. However, all the dyed fabrics displayed outstanding deodorizing performance(99%) against ammonia gas and antibacterial performance(bacteriostatic reduction rate:99.9%) against Staphylococcu aureus and Klebsiella pneumonia(bacteriostatic reduction rate: 99.9%). It is worth noting that pomegranate (Punica granatum L.) colorants notably enhanced the deodorizing and antibacterial performance of cotton, silk and wool fabrics.

• Journal of Sericultural and Entomological Science
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• v.39 no.1
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• pp.62-66
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• 1997

The MAA graftings in silk fiber were done by redox system for the purpose of investingating the effect of ferrous sulfate additive on the grafting rate and graft ratio in various conditions. The graft ratio was higher in redox graft system than in peroxide graft system and the graft ratio in redox graft system was also higher depending on decrease of ferrous sulfate additive. The saturation graft ratio obtained by empirical equation, log X=K/t, was increasing depending on the increase of ferrous sulfate additive. Initial grafting rate was increased but the latter grafting rate was decreased in redox graft system. The effects of liquor ratio(L.R.) on the graft ratio in redox graft system, were higher in high L.R. than in low L.R..