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Volume 3, No.4/2003
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FREE WOOL-FIBRE SHAPES
Clive Marsh, Bernie Tsang and Andy Wilkins
WRONZ, Private Bag 4749, Christchurch, New Zealand
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.
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BIOMIMETIC MANUFACTURING OF
CUSTOMISED NOVEL FIBRE PROTEINS FOR SPECIALISED APPLICATIONS
Florence Teulé1,
Cécile Aubé1, Michael Ellison2, Albert
Abbott1
1Dept. of Genetics
and Biochemistry and 2School of Materials Science and
Engineering, Clemson University, Clemson, SC 29634, USA
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).
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MODELLING AND SIMULATION OF THE MECHANICAL BEHAVIOUR OF
WEFT-KNITTED FABRICS FOR TECHNICAL APPLICATIONS
Part II: 3D model based on the elastica theory
M. de Araújo, R. Fangueiro
and H. Hong
University of Minho, Guimarăes, Portugal
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.
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HIGH-QUALITY COLOUR REPRODUCTION ON JACQUARD SILK TEXTILE FROM
DIGITAL COLOUR IMAGES
Keiji Osaki
International Christian
University, Department of Natural Sciences
NS 3-10-2 Osawa, Mitaka-shi, Tokyo 181-8585 Japan
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.
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ELECTROACTIVE FABRICS AND WEARABLE BIOMONITORING DEVICES
Danilo De Rossi°, Federico
Carpi°, Federico Lorussi°, Alberto Mazzoldi°, Rita Paradiso*, Enzo
Pasquale Scilingo°, Alessandro Tognetti°
° E. Piaggio Interdepartmental Research Centre , Faculty of
Engineering, University of Pisa
via Diotisalvi, 2, 56100 Pisa, Italy
*Smartex s.r.l., via Giuntini, 13 – 56023 Navacchio, Pisa, Italy
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.
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BARRIER EFFECT OF WOVEN FABRICS USED FOR SURGICAL GOWNS
Dilibaier Aibibu, Beata
Lehmann, Peter Offermann
Dresden University of
Technology, Institute of Textile and Clothing Technology
D - 01062 Dresden, Germany
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.
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SURFACE CHARACTERISATION OF LOW-TEMPERATURE PLASMA TREATED WOOL
FIBRE
Kan Chi-wai, Chan Kwong and
Marcus Yuen Chun-wah
The Institute of Textiles and Clothing, The Hong Kong Polytechnic
University,
Hung Hom, Kowloon, Hong Kong, China
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.
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ENVIRONMENTAL INDICATORS OF TEXTILE PRODUCTS FOR ISO
(TYPE III) ENVIRONMENTAL PRODUCT DECLARATION
Eija Nieminen-Kalliala
Tampere University of Technology, Institute of Fibre Materials
Science
PO Box 589, 33101 Tampere, Finland
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 Öko-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.
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PROCESS-ORIENTED ANALYSIS
Andrea Weber Marin, Simone
Creux, Urs Meyer
Institute for Manufacturing Automation, Swiss Federal Institute of
Technology Zürich
ETH Zentrum, Tannenstr. 3, 8092 Zurich, Switzerland
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.
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