Increasing skin wetness tends to increase fabric–skin adhesion and friction, resulting in wear discomfort or skin injuries. Here, the magnitude estimation approach was used to assess the stickiness sensation perceived in fabrics. Seven fabric types were wetted by putting onto wet ‘skin’ surface and dried for different durations to achieve different wetness levels, simulating wearing conditions during the recovery period after sweating. Results showed that the relationship between magnitude estimates of stickiness and amount of water present in fabric demonstrated a power function. The exponents and constant from power regression show the growth rate of stickiness sensation with moisture intensity and the perceived stickiness under fixed stimulus intensity, respectively. A novel parameter, accumulated stickiness magnitude (ASM), describing how much discomfort a wetted fabric offered throughout the drying period, was developed. Thin cotton fabrics (fabric W01 and W03), having higher saturation level after contacting with wetted skin surface, arouse stronger stickiness feeling and their ASM is remarkably higher. The difference in stickiness estimates is due to the difference in chemical composition and surface geometry. This study suggests us the way to predict perceived stickiness in fabrics with different wetness levels which is useful for applications like sportswear, intimate apparel or healthcare products.

Recently, researchers have become interested in exploring applications of rechargeable battery storage technology in different disciplines, which can help our daily life, such as textile-based supercapacitors. This paper briefly describes this development and classification of supercapacitors. Besides, various types of materials which are commonly used to prepare supercapacitors, such as carbons, metal oxides, alkaline earth metal salts and polymers, are introduced. Moreover, applications and methodology to prepare textile materials with supercapacitors are described. Finally, the commonly used non-destructive measuring methods for textile-based supercapacitors are also introduced.

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Water absorption and transport property of textiles is important since it affects wear comfort, efficiency of treatment and functionality of product. This paper introduces an accurate and reliable measurement tester, which is based on gravimetric and image analysis technique, for characterising the transplanar and in-plane wicking property of fabrics. The uniqueness of this instrument is that it is able to directly measure the water absorption amount in real-time, monitor the direction of water transport and estimate the amount of water left on skin when sweating. Throughout the experiment, water supply is continuous which simulates profuse sweating. Testing automation could even minimise variation caused by subjective manipulation, thus enhancing testing accuracy. This instrument is versatile in terms of the fabrics could be tested. A series of shirting fabrics made by different fabric structure and yarn were investigated and the results show that the proposed method has high sensitivity in differentiating fabrics with varying geometrical differences. Fabrics with known hydrophobicity were additionally tested to examine the sensitivity of the instrument. This instrument also demonstrates the flexibility to test on high performance moisture management fabrics and these fabrics were found to have excellent transplanar and in-plane wicking properties.

The water absorption and transport properties of fabrics are critical to wear comfort, especially for sportswear and protective clothing. A new testing apparatus, namely Forced Flow Water Transport Tester (FFWTT), was developed for characterizing the transplanar and in-plane wicking properties of fabrics based on gravimetric and image analysis technique. The uniqueness of this instrument is that the rate of water supply is adjustable to simulate varying sweat rates with reference to the specific end-use conditions ranging from sitting, walking, running to other strenuous activities. This instrument is versatile in terms of the types of fabrics that can be tested. Twenty four types of fabrics with varying constructions and surface finishes were tested. The results showed that FFWTT was highly sensitive and reproducible in differentiating these fabrics and it suggests that water absorption and transport properties of fabrics are sweat rate-dependent. Additionally, two graphic methods were proposed to map the direction of liquid transport and its relation to skin wetness, which provides easy and direct comparison among different fabrics. Correlation analysis showed that FFWTT results have strong correlation with subjective wetness sensation, implying validity and usefulness of the instrument.

Composite films consisting of lead zirconate titanate ͑PZT͒ inclusions dispersed in a matrix of polymer electrolyte the polyethylene oxide were fabricated. Their piezoelectric coefficients d 33 and pyroelectric coefficients p are increased almost proportional to the volume fraction of the ferroelectric ceramic phase. For 34% PZT composite, d 33 and p are 170 pC/ N and 120 C / m 2 K, respectively, they are much larger than PZT/polyvinylidene fluoride-trifluoroethylene composite with similar ceramics content. It is believed that the enhancement of the measured coefficients is due to the relatively high electrical conductivity of polymer electrolyte matrix. This is confirmed by theoretical models which consider the conductivity of matrix. © 2007 American Institute of Physics. ͓DOI: 10.1063/1.2827571͔Composites of polymer matrix mixed with ferroelectric ceramics have been well studied and their pyroelectric and piezoelectric properties are widely applied in various areas. [1][2][3][4][5][6] The ferroelectric ceramics inclusions play the role to provide the functional effects and the polymer matrix usually serves to provide good protection of the ceramic phase while maintains the compliant mechanical property. The advantages of these polymer composites with piezoelectric or pyroelectric functions are that they can be easily made to large area to increase sensitivity as sensors, they are flexible that intimate contact with the objects to be detected is possible, this is particularly important in vibration sensing application. However, even though the functional ceramics have high piezoelectric and pyroelectric coefficients, the effective coefficients of the composites are relatively low, for example, the pyroelectric coefficients p of lead zirconate titanate ͑PZT͒ ͑30 vol % ͒/polyvinylidene fluoridetrifluoroethylene ͑PVDF-TrFE͒ is 21% of the pure PZT ceramics at room temperature, 7 as their p's are 73 and 352 C / m 2 K, which hinders the realization of practical use of the polymer composites.From our previous study, 8 a 0-3 composite of 30 vol % PZT with a thermoplastic polyurethane ͑PU͒ shows a pyroelectric coefficient of 90 C / m 2 K at room temperature, around 27% of pure PZT, which is much higher than the PZT/PVDF-TrFE composite of the same ceramic volume fraction. As the PU used in the study has a higher electrical conductivity than other insulating polymers, this interesting result reveals the contribution of the electrical conductivity of the matrix which would enhance the pyroelectric coefficient of the composites. 8 It also encourages the application of other polymeric materials which has higher conductivity to further enhance the pyroelectricity or even piezoelectricity. Polyethylene oxide ͑PEO͒ is a well known polymer electrolyte which has been demonstrated a useful solid electrolyte for lithium battery. 9 The neat PEO has higher conductivity than PU by three orders of magnitudes. According to the theoretical model developed in the previous study, the PZT/ PEO composite is expected to have even a higher pyr...

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