This paper describes an objective evaluation method for fabric wrinkles of shirts formed after washing. The fabric wrinkle images were measured by texture analysis and evaluated subjectively by experts. The textural features of wrinkle images have a significant correlation with wrinkle grades evaluated by experts. A principal component analysis with textural features of images was carried out, and also a multiple regression analysis was carried out using the two principle component scores as explanatory variables and wrinkle grades evaluated by experts as criterion variables. As the result, we proposed an objective evaluation equation for predicting wrinkle grades. It was found that the wrinkle grades predicted by the equation have a significant correlation with the result of subjective evaluation, and the fabric wrinkles of shirts after washing is objectively evaluated with our proposed equation.

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Rodlike samples were made from Polypropylene (PP)/Poly(ethylene-co-vinyl alcohol) (EVOH) core/sheath composite fibers. From these rodlike samples, ultra thin fibers were produced using a melt-electrospinning system equipped with a CO₂-laser melting device. The effects of structure of rods on the morphology and structure of electrospun fibers have been investigated. The following conclusions were reached: (i) electrospun fibers about 1mm in diameter can be obtained using the system developed; (ii) the diameter of electrospun fiber is influenced by the PP content, the feed rate (Fr) of the rod and the molten end-to-collector distance (Cd); (iii) in the case of spinning of core/sheath single rods, electrospun fibers having trough structure are obtained by the extraction of EVOH component; (iv) in the case of spinning of the fiber bundles, the diameters of electrospun fibers are not influenced by the diameter of the rod; and (v) laser heating decreases the melting points of PP and EVOH.

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In order to understand the relationship between the internal defects of yarn structures and the mechanical properties of yarn, we developed a yarn model which consists of mass and three types of springs for expression and construction, and bending. The yarn model can express the Euler buckling phenomenon depending on its bending stiffness. Using the yarn model, the tension relaxation simulations of the yarn package structures were performed, and it was found that our yarn model has a suffcient ability to express the influence of the bending property of yarn on the internal defects like the circular buckling of the yarn package structures.

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Environmental problems caused by extensive use of polymeric materials arise mainly owing to lack of landfill space and depletion of finite natural resources of fossil raw materials like petroleum or natural gas. The substitution of synthetic petroleum-based resins with natural biodegradable resins appears to be one appropriate measure to remedy the above-mentioned situation.
This study presents the development of a composite that uses environmentally degradable starch-based resin as matrix and natural mineral basalt fibres as reinforcement. Unidirectional prepreg-sheets using basalt fibre roving and bidirectional sheets using plain weave fabric were manufactured by means of a modified doctor blade system and hot power press. The sheets were used to manufacture specimens with fibre volume contents ranging from 33% to 61%. The composite′s mechanical properties were investigated depending on modifications to the processing method and on variation of the fibre volume fraction. Composites manufactured during this study exhibited tensile and flexural strength of up to 517 MPa and 157 MPa, respectively.

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