FREE WOOL-FIBRE SHAPES
Eighteen cleaned and degreased Perendale wool fibres, which were as free as possible from external and internal stresses, were photographed, the images scanned to computer, and their space curves reconstructed. Various relations between the fibres' curvature and torsion were discovered which point to the possibility of a statistical description of a free fibre's shape in terms of only a few easily measured quantities, including the mean and RMS curvature. An algorithm is given which allows the generation of realistic wool fibre shapes for use in computer simulations.
BIOMIMETIC MANUFACTURING OF CUSTOMISED NOVEL FIBRE PROTEINS FOR SPECIALISED APPLICATIONS
Using spider silk and collagen as a model, we have investigated the role that various protein primary structural components play in fibre production. Spidroins, spider dragline silk protein components, are essentially characterised by an amino-acid repeat containing a glycine-rich ??[[motif]] (amorphous) followed by an alanine-rich motif (crystalline, putatively responsible for fibre strength). We have tested the importance of alanine runs in these proteins and the role of this motif in the mechanical properties of the resulting fibre. To test the importance of alanine-rich motifs in the spidroin-1 proteins, we engineered three types of spidroin-1-like genes containing sequence encoding for different amounts of alanine repeats in the protein (normal, low, and no alanine residues). We also have engineered three copolymer collagen-spidroin-1 genes using each of the three spidroin-1 synthetic genes. These copolymers were mimicked on the existing natural block collagen-silk-like protein copolymer found in the byssus thread of marine mussels. All of these constructs were introduced in yeast (Pichia pastoris) for protein production. We are currently purifying each of the recombinant proteins for structural analysis (CD-spectroscopy).
MODELLING AND SIMULATION OF THE MECHANICAL BEHAVIOUR OF WEFT-KNITTED FABRICS FOR TECHNICAL APPLICATIONS Part II: 3D model based on the elastica theory
This paper is in four parts. The first is related to general considerations and experimental analyses, and each of the others is related to different approaches to the theoretical analyses of the mechanical behaviour of weft-knitted fabrics and weft-knitted reinforced composites made of glass fibre. The objective is to find ways of improving the mechanical properties and simulating the mechanical behaviour of knitted fabrics and knitted reinforced composites so that the engineering design of such materials and structures may be improved.
In Part II the first model is presented, a 3D model based on the classic elastica theory which is used to calculate the load-extension curves of a plain weft-knitted fabric in the coursewise and walewise directions. Good agreement is obtained between theoretical and experimental results.
HIGH-QUALITY COLOUR REPRODUCTION ON JACQUARD SILK TEXTILE FROM DIGITAL COLOUR IMAGES
High-quality colour reproduction on silk textile was achieved from digital colour images by a precise colour-matching technique between original images on the monitor display and woven fabrics. More than a thousand various colours have been reproduced correctly with the use of only eight kinds of dyed wefts. Silk fabrics with a complex colour pattern in a width of 50 cm and a height of 75cm can be woven by an electronic Jacquard loom in just a few hours. The method of the colour reproduction on the silk textile bears a certain resemblance to ordinary painting. First, we prepare a 'colour textile block' database, that is, a kind of colour lookup table which plays the role of the palette in painting. A colour textile block is a woven silk sample textile of small size that shows various colours on a silk textile by a combination of textile structures and a few selected colour wefts among eight wefts. Colour attributes such as brightness, hue and chroma in the uniform colour space (CIEL*a*b*) of the colour textile blocks are measured by a colorimeter and stored in the colour textile block database. Second, we convert the pixels of original digital colour images into colour data of colour textile blocks, so as to minimise the colour differences between the colour attributes of the pixels in the original digital colour images and those of the colour textile blocks corresponding to the pixels. Third, on the monitor display we simulate the colour attributes of the textile to be woven from the assembled sets of colour textile blocks. Finally, we can produce fabrics on which the original colour digital image is reproduced in a manner resembling a colour photo. The estimation of the quality for the woven fabrics was carried out by several methods that exploit a colorimeter, a flatbed scanner and/or a digital still camera.
ELECTROACTIVE FABRICS AND WEARABLE BIOMONITORING DEVICES
The implementation of truly wearable, instrumented garments which are capable of recording biomechanical variables is crucial in several fields of application, from multi-media to rehabilitation, from sport to artistic fields.
In this paper we discuss wearable devices (a smart shirt, a leotard and a glove) which can read and record the vital signs and movements of a subject wearing the system. The sensing function of the garments is based on piezo-resistive fabric sensors, based on carbon-loaded rubbers (CLR) and different conductive materials.
BARRIER EFFECT OF WOVEN FABRICS USED FOR SURGICAL GOWNS
Surgical gowns must have a barrier effect between the sources of infection and the user (i.e. a healthy person), as well as good wearing comfort. They are often made of woven polyester fabrics. Different fabric constructions are available for this purpose; these are evaluated with reference to their barrier properties.
We present an optical method of obtaining cross-section figures of woven fabrics. The fabric is cut in warp and weft directions, and embedded perpendicularly in a cylindrical sample carrier using an epoxy resin. After the manufactured samples have hardened, they are smoothened and polished. Subsequently, images of the cross-sections of the fabrics are obtained by using an optical microscope linked to a digital camera and a computer.
The images show the microstructure of the woven fabrics, i.e. the size and distribution of the pores in the filament yarn, and between the filament yarns with respect to the fabric weave and yarn density. The porosity is determined by image analysis methods using ImageC ® by Aquinto. The distributions of the width of the pores and of the pore areas are calculated. Pore channels are shown.
The results of structural barrier effect are compared with the results of penetration tests. Synthetic blood or particle-loaded liquids containing microspheres comparable with the sizes of bacteria are used. The time necessary to soak the fabric with liquids or the contamination on the back of the fabric is determined.
SURFACE CHARACTERISATION OF LOW-TEMPERATURE PLASMA TREATED WOOL FIBRE
Previous investigation results revealed that after the Low-Temperature Plasma (LTP) treatment, the hydrophilicity of wool fibres was improved significantly. Such an improvement enhances the wool dyeing and finishing processes which might be due to the wool surface changing to a more reactive one. In this paper, wool fibres were treated with LTP with different gases, namely oxygen, nitrogen and a mixture of gases (25% hydrogen, 75% nitrogen). Investigations showed that the chemical composition of the wool fibre surface varied differently with different plasma. The variation of surface composition influences the hydrophilicity of the wool fibres. The surface chemical composition of the LTP-treated wool fibres was characterised by different characterisation methods, namely FTIR-ATR, XPS and saturated adsorption value. The experimental results of these methods are thoroughly discussed.
ENVIRONMENTAL INDICATORS OF TEXTILE PRODUCTS FOR ISO (TYPE III) ENVIRONMENTAL PRODUCT DECLARATION
The objective of this research project was to develop technical environmental indicators of textile products for ISO Type III environmental product declaration. The standardisation of an environmental declaration for products (Type III) currently under way in the ISO offers an interesting opportunity for communicating the environmental effects of products in a global and uniform manner. The research was conducted in co-operation between the Tampere University of Technology, the Federation of Finnish Textile and Clothing Industries and the more important Finnish textile producers and sellers. This paper examines the manufacturing processes of the selected textiles by using Life Cycle Inventory Analyses (LCI) of the Life Cycle Assessment (LCA) method, and also compares the data available with the criteria for different environmental labels (EU eco-labelling and the Oko-Tex standard). As a result of this research project, a proposal is presented for the formulation of technical environmental indicators of different types of textile products, i.e., of essential environmental effects, to support the development of ISO Type III environmental declaration criteria.
The consistency in logic between a stationary, process-oriented description of the system and its state-oriented counterpart is an important requirement imposed by automated manufacturing systems. In the late 1980s, computer-aided software engineering tools were developed to work with complex software systems. With these, the focus was on immaterial flows such as data and information. In searching for a method that could graphically describe complex systems, we developed our new methodology, Process-Oriented Analysis (POA). We have enriched the basic static diagram types of Structured Analysis with value and resource flows, and introduce consistent rules for the handling of resources, costs and data. The dynamic diagram types serve to describe the behaviour of the system, and lead to the programming of simulations and machine controls.
The static diagram types reveal the structure of the system as flows and processes. The diagrams are hierarchically structured on several levels of detail, allowing an in-depth analysis of complex systems with numerous sub-systems. A system optimisation is possible based on costs or on energy. The dynamic diagrams support plant simulation, real-time monitoring and control systems, and sustainability models. The dynamic diagrams are consistent with the static diagrams, and simplify program design and coding.