• Title/Summary/Keyword: regain

Search Result 267, Processing Time 0.02 seconds

Changes in Physical Properties of Paper by Solvent-Bonding between Cellulose Fibers Using Aqueous Solution of N-Methylmorpholine N-Oxide (N-Methylmorpholine N-Oxide 수용액을 이용한 셀룰로오스 섬유들간의 용제접착에 의한 종이의 물성 변화)

  • 이양헌;박찬헌;이현진;이선희
    • Textile Coloration and Finishing
    • /
    • v.11 no.1
    • /
    • pp.34-41
    • /
    • 1999
  • To examine the increase of paper strength by solvent-bonding using N-methylmorpholine N-oxide (NMMO), a paper was treated with aqueous solutions of NMMO, concentrated at $90^\circ{C}$ for selected periods of time, and pressed for 5 seconds followed by washing and drying. The effect of the increasing NMMO concentration on bonding state and some important properties of samples were mainly investigated. With increasing concentration of NMMO, the degree of bonding between fibers was increased, the fiber cross-sectional shape was changed from 'thin ribbonlike' to 'round rodlike' by swelling with solvent, and the longitudinal waves (crimp) were introduced to fibers, hence the shrinkage, weight per unit area, and thickness of paper were increased. Consequently, the tensile strength and elongation, under standard and wet conditions, and the stiffness were increased, and the water absorption was decreased generally with increasing concentration of NMMO. The moisture regain of treated samples was lower than that of the untreated sample, because of the reduction of space between fibers. But the moisture regain was increased a little with increasing concentration of NMMO due to the fiber swelling with NMMO followed by structural relaxation.

  • PDF

Effect of Sodium Sulfate on Ramie Fabrics Treated with Pectinase (저마직물의 펙티나제 정련 시 황산나트륨의 영향)

  • Park, So-Young;Song, Wha-Soon;Kim, In-Young
    • Textile Coloration and Finishing
    • /
    • v.22 no.3
    • /
    • pp.220-228
    • /
    • 2010
  • This study examines the scouring effect of pectinase on ramie fabric and influence of sodium sulfate as an activator for pectinase. The scouring effects were measured by the weight loss and pectin contents. SEM, weight loss, stiffness, moisture regain and dye ability of ramie fabric teated with pectinase/sodium sulfate were also measured. When ramie fabrics were desized with $\alpha$-amylase, the optimum conditions were pH 6.5 at $60^{\circ}C$ for 80 min with 1%(o.w.f) $\alpha$-amylase concentration. When ramie fabrics were scoured with pectinase, the optimum conditions were pH 8.5 at $55^{\circ}C$ for 30 min with 10%(o.w.f) pectinase concentration. Addition of sodium sulfate improved enzyme activity significantly, which increased proportionally with increasing sodium sulfate concentration. When 50 g/l of sodium sulfate was added, the surface became cleaner compared to the enzyme treatment without salt: weight and tensile loss, moisture regain and dyeability of the treated fabrics increased, while pectin contents and stiffness decreased. Therfore, sodium sulfate was effective activator for the pectinase treatment of flax fiber.

The Thermal Characteristics of Cellulose Fabrics Finished with Urea-Formaldehyde Resin (요소.포름알데히드 수지가공 셀룰로오스계 직물의 열특성)

  • Song, Wha Soon
    • Textile Coloration and Finishing
    • /
    • v.5 no.4
    • /
    • pp.79-91
    • /
    • 1993
  • The purpose of this study is to prepare the newer, more comfortable of urea-formaldehyde resin finished fabrics. The methods of this study are by making examinations and comparisons the relations between the thickness, fabrics counts, weight, moisture regain and crease recovery of cotton and viscose rayon fabrics caused by condition of urea-formaldehyde resin finishing and warm retaining ability and warm-cool sense. The analytic results of thermal character in state of fabrics material finished with urea-formaldehyde are as follows: 1. The warm retaining ability has no correlation with mixing ratio of resin but the increase of the warm retaining ability has correlation with the increase of concentration of urea-formaldehyde resin. 2. The result pf multiple regression analysis for effect of physical property according to the concentration of resin to the warm retaining ability revealed as below. As the weight, thickness and density increase and moisture regain decreases, the warm retaining ability increases. 3. The qmax value has no correlation with mixing ratio of resin but the increase of the qmax value has correlation with the increase of resin concentration. In the end, the effect of it promotes cool sense. 4. The result of multiple regression analysis for effect of physical property according to the concentration of resin to the qmax value revealed as below. As he weight and thickness increase, the qmax value decrease. But, as the density and crease recovery increase, the qmax value increase.

  • PDF

A Study on the Chitosan Treatment of Polyester Fabrics by Low Temperature Plasma Method (저온 플라즈마법에 의한 폴리에스테르 직물의 키토산 처리가공에 관한 연구)

  • Park, Seong-Woo;Lee, Suk young;Cho, In-Sul;Cho, Hwan
    • Textile Coloration and Finishing
    • /
    • v.9 no.5
    • /
    • pp.42-51
    • /
    • 1997
  • The purpose of this article is to investigate the effect of $O_{2}$ low temperature plasma treatment oft chitosan treatment of polyester fabrics. Moisture regain, static charge, crease resistance and reduction ratio of the treated fabric were measured. The results of this study were as follows: The add-on ratio and. the moisture regain of polyester fabrics treated with chitosan after treated by plasma(CP PET) were higher than those of polyester fabrics treated with only chitosan(C PET). The static charge of polyester fabrics decreased greatly with increasing the concentration of chitosan. A durability for laundering of CP PET was higher than those of C PET. The crease resistance of polyester fabrics decreased with ihcreasing the concentration of chitosan continuously. CP PET had higher decreasing rate and better durability than C PET. It showed that chitosan-treated polyester fabrics had over 90% reduction ratio after 10 times of laundering, and CP PET had better reduction ratio than C PET.

  • PDF

A Study on the Water Absorption Velocity of Sized Fabrics (푸새직물의 흡수속도에 관한 일연구)

  • 오화자
    • Journal of the Korean Home Economics Association
    • /
    • v.25 no.2
    • /
    • pp.31-38
    • /
    • 1987
  • This paper aims to examine the velocity of water absorption of cotton, hemp, and T/C fabrics sized by rice, wheat, potato, corn flour and pp.V.A.. Experimental variables such as the concentration of sizing agents, the moisture regain of unsized fabrics and the ironing temperature showed the following results. 1. When the fabrics were sized, the velocity of water absorption increased according to the order of corn, rice, potato, wheat flour and pp.V.A. for cotton fabrics, of corn, potato, rice, wheat flour and pp.V.A. for hemp fabrics, and of corn, wheat, rice, potato flour and pp.V.A. for T/C fabrics; corn flour showed the highest velocity of water absorption and pp.V.A. did the lowest among all the others mentioned above. 2. The higher fabric density, the higher velocity of water absorption. The finer the count of fabric yarn, the higher velocity of water absorption. 3. The material of sized fabrics most affected the velocity of water absorption than other factors of those. 4. To a certain extent, the higher the concentration of sizing agent, the higher the velocity of water absorption. 5. The fabrics with moisture regain of 20% before sizing showed the highest velocity of water absorption. 6. The ironing temperature after sizing fabrics mentioned below showed the highest velocity of water absorption; 180$^{\circ}C$ for cotton, 200$^{\circ}C$ for hemp, and 160$^{\circ}C$ for T/C fabrics.

  • PDF

Biodegradabilities of Cotton Fabrics treated with Silicones (실리콘 처리한 면직물의 생분해성)

  • 김보형;박정희;임승순
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.28 no.8
    • /
    • pp.1048-1056
    • /
    • 2004
  • Hydrophilicities of finished cotton fabrics were evaluated in respect of moisture regain and wickability. Changes in internal structure were determined using X-ray diffraction and surface changes in degraded samples were observed through a microscopy. Activated sludge test, soil burial test and enzyme hydrolysis were employed to evaluate the biodegradabilities. In addition, correlation analysis was done between biodegradability and the factors affecting biodegradability in each evalution methods. It was shown that hydrophilicities of silicone finished specimens were lower than that of untreated cotton and decreased in a row of PDMS(polydimethyl siloxane : -CH$_3$)>AFS(amino functional siloxane ; -C$_3$H$_{6}$ NHC$_2$H$_4$NH$_2$)>MHPS(methylhydrogen polysiloxane : -H, Cat : (C$_{17}$ H$_{35}$ COO)$_2$Zn) Although, moisture regain of mercerized cotton was higher than those of the others, wickability was shown to be lower. It was represented that crystalinities of cotton fabrics decreased by the silicone treatment. In activated sludge test and soil burial test, biodegradabilities of silicone treated specimens were lower than that of untreated cotton, where specimens of higher biodegradability exhibited higher biodegradability except mercerized ones. The results from enzyme hydrolysis, however, showed somewhat different tendency in that biodegradability was more closely related with the crystallinities of fabrics. It can be thought that enzyme hydrolysis is carried out for short time, physical accessibility becomes important.

The Properties of Kenaf/Polyester Blended Nonwovens (케나프/폴리에스테르 혼방 부직포의 특성)

  • Lee, Hye-Ja;Yoo, Hye-Ja;Han, Young-Sook
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.31 no.7
    • /
    • pp.1119-1127
    • /
    • 2007
  • Nonwovens have been widely used in various regions from the households to the industrial, agricultural and medical goods. Synthetic fibers have been used for source of nonwovens commonly because of their useful and economic properties. They are not only main factor causing environmental problems but also spend huge cost to renew the environmental disruption by them. Nonwovens must have both cost-competitiveness and environment-friendly property to be the desirable sources in 21th centuries. For meet these needs, it is suitable for the times that economical and environmentally-safe kenaf fibers would be used as raw materials of nonwovens. Kenaf and polyester fibers were blended in 4 types of ratio : 0/100, 20/80, 40/60, 60/40 were needle-punched. The nonwovens properties such as color values, surface appearance, strength, elongations, stiffness, moisture regain, water and oil absorbency, and electrification were tested. As the results, tensile and tear strengths, water and oil absorbency were maximum at 20/80 kenaf/polyester blend nonwoven, because of effecting by nonwoven structure and fiber properties. The moisture regain were increased according to kenaf were blended and the eletrification reduced in proportion to the kenaf fibers by chemical property of fiber composed nonwovens.

Effects of Treatments with Two Lipolytic Enzymes on Cotton/Polyester Blend Fabrics

  • Lee, So Hee;Song, Wha Soon
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.37 no.8
    • /
    • pp.1107-1116
    • /
    • 2013
  • This study examined the use of cutinase and lipase to process cotton/polyester blend fabric. Optimum treatment conditions for cutinase and lipase were investigated for cotton/polyester blend fabric. The properties of enzyme-treated fabrics were evaluated and compared in optimal treatment conditions. In addition, the possibility to provide an enzymatic finishing on blend fabrics using mixed enzymes in a two-step process were studied. The weight loss of cotton/polyester blend fabrics with Triton X-100 was 0.8% and the dyeing property of blend fabrics with calcium chloride increased by a factor of 1.2. The use of two enzymes in combination with cutinase and lipase in the presence of auxiliaries resulted in a cotton/polyester blend fabric weight loss of 0.8%. In addition, the dyeing properties of cotton/polyester blend fabrics improved by a factor of 1.5 and the moisture regain of cotton/polyester blend fabrics improved by a factor of 1.16. However, no marked loss was observed in tensile strength. The surface morphology of cotton/polyester blend fabrics is modified through a two-enzyme treatment. The treatment of cotton/polyester blend fabrics with cutinase and lipase maintains cotton strength and improves the moisture regain of polyester fabrics.

Studies on Utilization of Chitosan for Fixation of Copper Compound in Wood Preservative Treatment (목재방부리(木材防腐理)에 있어서 구리화합물(化合物) 정착제(定着濟)로서 키토산 이용(利用)에 관한 연구(硏究))

  • Lee, Jong-Shin
    • Journal of the Korean Wood Science and Technology
    • /
    • v.25 no.4
    • /
    • pp.92-98
    • /
    • 1997
  • To make good use of chitosan forming complex with heavy metals in wood preservative treatment, woods impregnated with chitosan and copper sulfate were prepared. Amounts of leached copper, decay resistance, anti-mold efficacy, iron corrosion rates, moisture regain rates and degradation pattern in chitosan pre-treated and untreated wood were compared. After leaching test, amounts of leached copper from chitosan pre-treated wood had a much smaller than chitosan untreated wood, and good decay resistance was retained even after leaching test. From these results, it was proved that chitosan-copper complex formed in wood played and important role for decay durability. In chitosan pre-treated wood, damage values by test molds became remarkably smaller, but the growth of test molds was not perfectly inhibited. Distinct differences in iron corrosion rates between chitosan pre-treated and untreated woods was not recognized but chitosan pre-treated wood showed the lower moisture regain rates than chitosan untreated wood because of water insoluble chitosan membrane formed in wood. After leaching test, the tracheid walls in the wood treated with 2.0% copper sulfate only were eroded by the fungal attacks, but those in the wood pre-treated with chitosan remained almost intact.

  • PDF

Dynamic Energy Balance and Obesity Prevention

  • Yoo, Sunmi
    • Journal of Obesity & Metabolic Syndrome
    • /
    • v.27 no.4
    • /
    • pp.203-212
    • /
    • 2018
  • Dynamic energy balance can give clinicians important answers for why obesity is so resistant to control. When food intake is reduced for weight control, all components of energy expenditure change, including metabolic rate at rest (resting energy expenditure [REE]), metabolic rate of exercise, and adaptive thermogenesis. This means that a change in energy intake influences energy expenditure in a dynamic way. Mechanisms associated with reduction of total energy expenditure following weight loss are likely to be related to decreased body mass and enhanced metabolic efficiency. Reducing calorie intake results in a decrease in body weight, initially with a marked reduction in fat free mass and a decrease in REE, and this change is maintained for several years in a reduced state. Metabolic adaptation, which is not explained by changes in body composition, lasts for more than several years. These are powerful physiological adaptations that induce weight regain. To avoid a typically observed weight-loss and regain trajectory, realistic weight loss goals should be established and maintained for more than 1 year. Using a mathematical model can help clinicians formulate advice about diet control. It is important to emphasize steady efforts for several years to maintain reduced weight over efforts to lose weight. Because obesity is difficult to reverse, clinicians must prioritize obesity prevention. Obesity prevention strategies should have high feasibility, broad population reach, and relatively low cost, especially for young children who have the smallest energy gaps to change.