Laundering is required for many textile products, but it degrades the fabric performance. We have quantitatively investigated the relationship between the number of laundering cycles and several key fabric performance parameters. The effects of crease resistant treatment are also examined.
As expected, increased laundering gradually decreases the fabric strength. However, the fabric abrasion resistance is increased by laundering. This is caused by fabric shrinkage which increases the tightness, thickness and areal density of the fabric. The crease resistant treatment improves the fabric dimensional stability, but reduces the fabric strength.

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Optical non-contact measurement for the surface properties of woven fabrics was successfully realized by using an optical fiber bundle and a photosensor. Experiments done on six woven fabrics revealed that the adjectives “brightness”. “roughness”. and “luster” evaluated by human visual sensation had high correlation with the optical intensities measured by this method. This optical method could measure multi properties simultaneously by changing the sensor head and offer not only a new method, but also an automatic on-line sensor for the surface properties of the woven fabrics.

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This paper describes the method evaluating the appearance of fabric-wrinkling replicas objectively by image processing. Results indicate that the wrinkle can be reliably measured using the distribution of gray level and the ratio of surface area, the ratio of X-direction length and the one of Y-direction length of surface profiles. All parameters with wrinkling fall on good logarithmic functions, which have high correlation coefficients. All parameters used can quantify the wrinkle of replicas with AATCC grades. The profile lines of surface are also analyzed with the method of Fast Fourier Transform.

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Dynamic viscoelasticity was measured for melts of semi-aromatic liquid crystalline polymer (LCP) filled with:carbon fiber (CF) and glass fiber (GF) to quantitatively analyze their nonlinear viscoelastic properties. LCP and its CF and GF filled polymer systems were examined to analyze the dynamic viscoelastic behaviors by Fourier expansion of shear stress wave. For LCP the tertiary terms G'₃ and G₃ are considerably smaller than their primary terms G'₁, and G''₁; the viscoelastic property is almost linear. On the other hand, two types of CF filled LCP showed that an increase in the oscillatory angle decreased G'_i and G_i in sequence with increasing i. However, the G'₃ and G₃ values are large enough not to be negligible, i.e. both fiber filled systems show similar nonlinear viscoelastic behaviors. GF filled LCP showed the tendency similar to that for CF filled systems; both G'_i and G_i have apparently a plateau region. Furthermore, the values of the ratios G₃/G₁, G'₃/G'₁, and G₃/G₁, are recognized as the indicator of the degrees of their nonlinearity, and the fiber filled LCP systems showed no significant difference in their dependency on ω, although GF filled systems showed a markedly higher nonlinearity of G₃/G₁, than CF filled systems in a high ω region.

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The time dependence of elastic recovery was measured in the range of -30°C to 100°C for segmented poly(urethane-urea), which consists of soft and hard segments. The dependence of elastic recovery on the soft segment and its molecular weight and the improvement of elastic recovery at low temperature are discussed.
The instantaneous and delayed unrecovered strain at room temperature showed a minimum value at a molecular weight of about 2000 of poly(tetramethylene glycol)(PTMG). But the segmented poly(urethane-urea) based on the high molecular weight of soft segment easily crystallized due to stress-induced crystallization at low temperatures and had high elastic unrecovered strain. X-ray diffraction data suggest the formation of crystallites of soft segment such as PTMG or poly(caprolactone)(PCL), which did not melt even after release of stress at a temperature of 0°C.
Adding low molecular weight of fractionated PTMG was effective in preventing stress-induced crystallization. Copolymerization of two kinds of soft segment, such as PTMG and poly(propylene glycol)(PPG) or PTMG and PCL, in the stage of prepolymer reaction was very effective on elastic recovery at low temperatures. The experimental result shows that the block copolymerized PCL which was polymerized by using polyether of low molecular weight as an initiator improved elastic recovery at a wide range of low temperatures.
Elastic recovery rate at low temperatures depended on both micro-Brownian motion in relation to glass transition temperature and stress-induced crystallization of the soft segment. It was found that the rubber point Tr at which the material behaved most rubber-like related to the transition temperature Tα_a at which the material showed the maximum dynamic loss modulus by the following formula.
Tr=Tα_a+30

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