UNIVERSITY OF LEEDS ARS TEXTRINA INTERNATIONAL TEXTILES CONFERENCE JULY 21-22, 2005 FORM, MATERIALS AND PERFORMANCE A Selection of Papers Edited by B. G. Thomas The University of Leeds International Textiles Archive (ULITA), The University of Leeds, United Kingdom Copyright remains with the authors Contents Complex Geometric Patterning of Woven Fabrics by Incident Water Jets S. J. Russell, M. A. Hann and S. Sengupta 1 The Exquisite Linen of Beth Shean N. Ben-Yehuda 7 Affective Textile and Costume Museum Website Design F. S. Lin and T. Cassidy 15 Databank of Ornamental Woven Fabrics – The Lithuanian Experience J. Katunskis, V. Milasius and D. Taylor 22 How well can People Predict Subtractive Mixing? P. M. Henry and S. Westland 26 Southeast Asian Baskets: The Interface of Ethnobotany, Agriculture and Design V. Z. Rivers 32 Fabric Design Criteria for Reducing the Effect of Pilling in High Performance Fabrics M. Brookes, D. Brook and S. J. Russell 44 The History & Development of Bradford Industrial Museum and its Textile Collection E. Nicholson 50 The American Silk Crisis K. Dirks 53 Fleece - A World of Possibilities M. Goddard and D. Brook 64 Power, Pattern and Protection in Japanese Textiles M. Maule 68 Digital Printing – A 21st Century Paintbrush (Painting with Light, Colour and Image) R. Burton 71 Modern Education and Training for Textile Technologists and Managers A. Primentas 77 Conservation of the ‘Vane Tempest’ National Union of Mineworkers’ Banner J. Hyman 82 The Delaware Quilt Documentation Project: Piecing Together Delaware’s Quilting History F. W. Mayhew and J. A. Funderburk 85 i Development of Ornament Notation for Woven Fabrics - Our Approach V. Milasius, J. Katunskis and D. Taylor 88 The Woollen Beaded Fabrics Woven at the Town of Roubaix in 1886 A. Uhlenbeck 92 Conceptual Developments Associated with Structure, Form and Performance M. A. Hann and B. G. Thomas 100 The Launch of an International Design Archive M. A. Hann, P. W. G. Lawson and J. A. Smith 109 ii Complex Geometric Patterning of Woven Fabrics by Incident Water Jets S. J. Russell, M. A. Hann and S. S. Sengupta School of Design, University of Leeds, UK Corresponding author: [email protected] The introduction of complex Zillij-inspired patterns in dyed woven fabrics is described by impacting the surface with fine, high pressure water jets. The origins of the visual effects are discussed in relation to fabric structure and fibre composition. Patterning of the surfaces and the introduction of relief patterns may be introduced simultaneously on the face and back of the fabric when the incident jets are restricted to one side only. 1. Introduction Hydroentanglement (or spunlacing) is a nonwoven process in which fibres in a web structure are mechanically entangled by high pressure water jets to produce a coherent fabric. A derivative technique involves directing pressurised water jets at the surface of a preformed woven or knitted fabric to enhance physical properties and this is usually accompanied by certain changes in visual appearance. If the water jet impact is localised to specific regions of the fabric, visual patterns can be produced, which may be controlled by adjusting process parameters. Therefore, it is possible to make late-stage modifications to the appearance and physical properties of textile fabrics intended for use in apparel and upholstery. This paper is concerned with a preliminary exploration of the complex patterning effects that are introduced in dyed woven fabrics as a result of impacting the surface with small diameter water jets. It also considers the physical modifications to fibre, yarn and fabric structures that are associated with these changes in appearance. 2. Patterning of Fabrics by High Pressure Jets Two basic approaches can be adopted to pattern the surface of fabrics using water jets. The first uses an embossed support screen surface on which the target fabric sits. When the fabric is impacted by jets from above, the pattern produced corresponds to the solid or raised areas of the embossed support surface (Siegal et. al). Further improvements in the base technology have been made as understanding has advanced, for example (Greenway et. al). A second approach utilised in the present research, uses an upper permeable stencil screen placed on top of the fabric beneath the water jet manifold. This may be introduced continuously or discontinuously. A variation is to combine the use of both the upper stencil screen and lower embossed support screen. The basic elements of the process are illustrated in Figure 1. 1 Woven fabric is introduced on to a continuously revolving embossed support screen, which is water permeable to aid drainage and prevent flooding. Optionally, a second embossed stencil screen is introduced above the fabric and below the injector to enable simultaneous geometric patterning of the face and back of the fabric. A curtain of individual water jets extends across the width of the machine and treats the fabric in open width perpendicular to the plane. These jets are produced by pumping pressurised water through a drilled metal jet strip containing about 1000 nozzles/m arranged in a single line or in a twill format. The nozzles have a capillary cone cross-section to maximise energy transfer and jet stability and the stability and break-up length of the jets depends on the geometry of the nozzle and on the nozzle wear amongst other factors. Nozzle wear particularly on the input edge can be significant when operating at very high pressures and this affects the nozzle geometry leading to jet divergence and other faults as the nozzle geometry is changed. The incident water jets produce large impact forces and mechanical energy is transferred from the jet to the fabric and its constituent fibres. The dissipation of the water jet energy within the fabric and on the surface of the support conveyor also influences the visual effects produced in the fabric. The dissipation of energised water droplets reflected by the yarns in the fabric and the support surface are not fully understood, but also appear to influence the visual effects that are introduced. Injector Jet strip containing Water jet capillary cone nozzles (10-200 bar, up to 200m/s) Dissipation of jet and high energy water droplets Woven Permeable and fabric in Drainage, suction of water and air embossed support screen conveyors Figure 1. Basic Arrangement of a Hydropatterning System In low sett woven fabrics, yarns can be laterally displaced by incident water jets leading to variations in end and pick spacing and particularly in staple yarns, flattening and shifts in surface hairiness are frequently observed. The structure of both the constituent yarns and the geometric structure of the fabric both influence the visual and physical changes obtained in the fabric. Three-dimensional relief patterns are obtained by increasing the open area of the support screen and allowing the fabric to deform within these unsupported voids. Deep embossed effects can be produced in this way and can be stabilised by subsequent thermal bonding or the application of chemical binders. 2 3. Experimental: Introduction of Complex Geometric Patterns To understand the potential for complex patterning using water jets, the geometric patterns found in countless examples of Moroccan architecture and ceramics were adopted as designs for experimental work. These complex geometries derive from Zillij built from 360 pieces of different geometric patterns called Furmah. Zillij originated from the Roman art of mosaics which was strongly influenced by Greek civilisation. The geometric designs that are formed not only create a visual effect but are also designed to express the meaning or thoughts of the human mind. In this work, new designs inspired by Moroccan ceramics, plates and domestic-wear were developed and converted in to cut stencils composed of rigid PVC sheet (Figure 2). The cut stencil was placed on top of the woven fabric, which in turn was supported by a permeable, embossed mesh screen. An embossed mesh screen was employed as a lower screen as indicated in Figure 3. Figure 2. Arrangement of Patterning elements: lower screen (mesh) and upper screen (stencil) placed either side of the woven fabric Figure 3. Embossed Mesh Structure for Lower Screen A scoured 60g/m², plain woven 100% cotton fabric was direct dyed according to colour code 8 Pantone 16-4013 in preparation for the experiments. To enable the structural effects in the fabric to be clearly observed one injector was employed operating at a water pressure of 60 bar. 3 a) Upper patterning screen only (no lower screen) When the water jets were directed on to the fabric from one side only, through the upper screen, both sides of the fabric are patterned simultaneously, see Figure 4. a) Face b) Back Figure 4. Face and Back of Direct Dyed Woven Fabric (1 injector, 60 bar, upper screen fitted only) Dye is apparently removed from both faces of the fabric in those regions that are not obscured by the stencil and a pattern is therefore produced. Additionally, within each motif, periodic jet marks became visible producing additional colour contrast and surface interest. Clearly, the periodicity and intensity of these jet marks can be readily adjusted by modifying the nozzle arrangement (across and along the machine when utilising multiple injectors), jet pressure and number of passes. b) Upper and lower patterning screens The effect of fitting both upper and lower screens on fabric appearance is illustrated in the example given in Figure 5. The fabric was dyed according to colour code 54 Pantone 18-4320. This fabric was produced using two injectors each operating at 80 bar and the lower screen was employed. a) Face b) Back Figure 5. Face and Back of Direct Dyed Woven Fabric (2 injectors, 80 bar, introduced from one side, upper and lower patterning screens fitted) 4 The resulting pattern became more pronounced as the jet pressure and number of injectors increased and distinctive differences were observed in the textural effects produced within the motifs on the face and back of the fabric.