: To develop a waterproof breathable material, we fabricated three kinds of nanofiber web laminates using a mass-produced electrospun nanofiber web with different substrates and layer structures The waterproofness and breathabilityof nanofiber web laminates were evaluated after repeated launderings and compared with those of conventional waterproofbreathable fabrics currently in use, including densely woven fabric, microporous membrane laminated fabric, and coated fab-ric The durability of nanofiber web laminates, including adhesion strength, abrasion resistance, tensile strength, and tearingstrength, was also assessed and compared with those of conventional waterproof breathable fabrics The water vapor trans-mission of nanofiber web laminates increased slightly after repeated launderings, whereas the air permeability somewhatdecreased after launderings but still maintained an acceptable level of air permeability Laundering reduced the resistanceto water penetration of nanofiber web laminates, which implies that laminating techniques or substrate materials that couldsupport waterproofness of the laminated structure should be explored The adhesion strength, abrasion resistance, tensilestrength, and tearing strength of nanofiber web laminates were in a range comparable to conventional waterproof breathablematerialsKey words:electrospun nanofiber web laminate, waterproofness, breathability, launderability, durability

/pdf/changes-in-waterproofness-and-breathability-after-repeated-131oyrrq75.pdf

Changes in Waterproofness and Breathability after Repeated Laundering and Durability of Electrospun Nanofiber Web Laminates

In order to investigate the mechanical properties of working clothes materials considering industrial settings, the test weaving materials were compared with the existing materials depending on the season. The material design of the test fabrics were changed through fineness, composition, density of materials then subsequently treated with functional finish. As a result of evaluation of the forms according to KES-FB system, Koshi was deduced, and Numeri and Fukurami were increased. Thereby, the test weaving materials became flexible, surface became smoother, elasticity and volume characteristics indicated to have been improved. Consequently, the THV value of working clothes materials for test weaving was increased compared to existing materials which indicated improved result of the total hand value. Specially, the winter cloth material indicated improved drape characteristics and dimensional characteristics, showed improved liveliness as being compressed softly.

/pdf/the-mechanical-properties-of-working-clothes-materials-52ixc3zxq6.pdf

The Mechanical Properties of Working Clothes Materials Considering Industrial Settings

This study examines the rustling sound characteristics of electrospun nanofiber web laminates according to layer structures. This study assesses mechanical properties and frictional sounds (such as SPL); in addition, Zwicker's psychoacoustic parameters (such as Loudness (Z), Sharpness (Z), Roughness (Z), and Fluctuation strength (Z)) were cal- culated using the Sound Quality Program (ver.3.2, BK however, weight (T) with Sharpness (Z) and Roughness (Z), and bending hysteresis (2HB) with Roughness (Z) indicated positive correlation coefficients, respectively.

/pdf/characteristics-of-rustling-sound-of-laminated-fabric-erflwwny4q.pdf

Characteristics of Rustling Sound of Laminated Fabric Utilizing Nano-web

To investigate sound characteristics of PU-Nanoweb (NW) and PTFE film (PTFE) laminated vapor permeable water repellent fabrics, their frictional sounds by walking, jogging, and running speeds were recorded and sound characteristics such as SPL, loudness (Z), sharpness (Z), roughness (Z), and fluctuation strength (Z) were calculated. Mechanical properties were measured by KES-FB system. SPL and fluctuation strength (Z) were significantly increased by increasing speed. Roughness (Z) was generated to be the highest by jogging and running speeds. However, sharpness (Z) was decreased by increasing speeds. NW had significantly lower SPL, loudness (Z), but had higher roughness (Z) than PTFE. NW significantly had less B (bending rigidity), G (shear stiffness), WC (compressional energy), and W (weight). These distinctions influenced the sound characteristics to have the different sound between NW and PTFE. The sound would be low by controlling the mechanical properties and laminated nanoweb and film conditions. The crucial factors were RC and laminated nanoweb and film weight to minimize SPL and loudness (Z) of NW and PTFE at all speeds.

Minimizing frictional sound of PU-Nanoweb and PTFE film laminated vapor permeable water repellent fabrics

The aim of this study was to measure the functional properties of a nanofiber web laminate, microporous film laminate, and nonporous coating fabric and then compare their performances as a breathable waterproof fabric. We focused on the performance of the nanofiber web laminate as a breathable waterproof fabric. A PU nanofiber web was prepared by electrospinning. The measured functional properties included the water vapor permeability, air permeabil- ity, waterproofness, adhesive strength, and water vapor resistance, as well as the property of a warm/cool feeling. The measurement results showed that the nanofiber web laminate fabric provided excellent moisture permeability as well as sufficient waterproofness and water vapor resistance in comparison to the microporous film laminate and nonporous coating fabric. We concluded that the performance of the nanofiber web laminate is sufficient for use as cloth in out- door wear if an optimum electrospinning and lamination process is used in its production.

Performances of Breathable & Waterproof Jacquard Fabric with PU-Nanofiber Web and PU-Film

전기방사한 나노섬유 웹은 가는 섬유직경과 수많은 미세공극 구조로 인해 우수한 투습성 및 차단 성능을 나타내며, 초박막·초경량의 특성을 갖는다. 이러한 특성 때문에 새로운 투습방수 소재로서 전기방사한 나노섬유 웹을 이용하고자 하는 시도가 이루어지고 있으며, 본 연구에서는 나노섬유 웹 처리소재의 역학적 특성을 측정하고 이를 기존 투습방수 소재와 비교함으로써 기능적 성능과 더불어 감성적 성능을 만족시키는 새로운 투습방수 소재 개발을 위한 기초자료를 제시하고자 하였다. 실험실 제작(lab-scale) 나노섬유 웹과 대량생산 (commercial) 나노섬유 웹을 이용하여 웹 밀도와 기반 직물, 적층 구조, 라미네이팅 여부 등에 차이를 두어 다양한 전기방사 나노섬유 웹 처리소재를 제작하였다. 이들 시료에 대해 KES-FB system을 이용하여 역학적 특성을 평가하고, 이를 기존 투습방수 소재인 고밀도 직물, PTFE 라미네이팅 직물, PU 코팅 직물의 역학적 특성치와 비교하였다. 연구 결과, 실험실에서 제작한 나노섬유 웹 처리소재는 부피감이 있으면서 유연하였고, 대량생산된 나노섬유 웹을 라미네이팅한 소재는 신장 변형이 적은, 치밀한 구조의 소재인 것으로 나타났다. 또한 고밀도 직물과 실험실 제작 나노섬유 웹 처리소재는 낮은 인장선형성과 굽힘강성, 전단강성으로 유사한 거동을 나타내어, 기존 PU 코팅이나 PTFE 라미네이팅 직물에 비해 뻣뻣함이 덜하면서 유연하고 부드러운 태를 가지는 것으로 해석되었다. 따라서 전기방사 나노섬유 웹 처리소재가 일정 수준의 방수성을 확보한다면 기능적 성능과 감성적 성능을 모두 충족시키는 새로운 투습방수 소재로 이용될 수 있을 것으로 사료된다.

이승신 ( Seung Sin Lee )

Papers

전기방사한 나노섬유 웹 처리소재와 상용 투습방수소재의 역학적 특성 비교