Hydro-entanglement Bonding Process for Production of Nonwoven Fabric (Part-1)
Eng Mohamed Elsharkawy
Dept. of Textile Engineering
Dept. of Textile Engineering
Hydro-entanglement is a technique for mechanically bonding loses filaments or fibers arranged in the web. The efficiency with which the web is entangled depends on the peculiar properties of laminar high speed water jet used. In this project, a prototype of hydro- entanglement machine has been designed and manufactured to study the properties of the produced non woven and the factors affecting on the efficiency and fabric properties.
Hydro-entangling, spun lacing, hydraulic entanglement and water jet needling are synonymous terms describing the process of bonding fibers (or filaments) in a web by means of high-velocity water jets. The oldest technique for consolidating fibers in a web is mechanical bonding, which entangles the fibers to give strength to the web. Spun-lacing uses high-speed jets of water to strike a web so that the fibers knot about one another.
The interaction of the energized water with fibers in the web and the support surface increases the fiber entanglement and induces displacement and rearrangement of fiber segments in the web. In addition to mechanical bonding, structural patterns, apertures and complex three-dimensional effects are produced if required by the selection of appropriate support surfaces. Hydro-entanglement also provides a convenient method of mechanically combining two or more webs to produce multilayer fabrics.
Geo-textiles are permeable fabrics which, when used in association with soil, have the ability to separate, filter, reinforce, protect, or drain. Typically made from polypropylene or polyester, geo-textile fabrics come in three basic forms: woven (looks like mail bag sacking), needle punched (looks like felt), or heat bonded (looks like ironed felt).
Geo-textile composites have been introduced and products such as geo-grids and meshes have been developed.
Overall, these materials are referred to as geo-synthetics and each configuration geo-nets, geo-grids and others-can yield benefits in geotechnical and environmental engineering design.
To use geo-textiles to reinforce a steep slope, two components have to be calculated:
- The tension required for equilibrium
- The appropriate layout of the geo-textile reinforcement.
REVIEW OF LITERATURE
REVIEW OF LITERATURE
In textile industry, nonwoven industry is organized differently and separately from the traditional woven or knitting industry. Nonwovens are engineered fabrics, and have higher production rate, larger availability, and lower cost than traditional woven and knitting fabrics. So in many industries nonwoven fabrics are replacing the traditional fabrics.
Today’s nonwovens are highly engineered solutions made up of a variety of materials including fibers, powders, particles, adhesive, films and other materials that provide a multitude of functionalities, such as hospital supplies, hygiene applications, horticultural applications, consumer products, interlinings, geo-textiles, carpet backings, automotive parts, filters, wipes, etc.
The steps for producing nonwoven fabrics include: web formation, web entanglement, web drying and optional further treatments. Fibers or polymers are first processed to form webs. There are several processes to produce webs, such as dry-laid, wet-laid, air-laid, spun-bonding, and melt-blowing process. Then webs are bonded to produce nonwoven fabric through the bonding processes, such as needle punching, hydro-entangling, thermal, and chemical adhesive bonding.
2.2. Methodology of non-woven
Nonwoven emerged from the textile, paper and plastic industries and has, for over 40 years, evolved into a distinct industry. As the demand for non-woven has steadily increased, it has been met by the technology and ingenuity of raw materials and equipment suppliers, and non-woven producers and converters. The production of non-woven can be described as taking place in three stages, although modern technology allows an overlapping of some stages, and in some cases all three stages can take place at the same time .
|Figure (2.1): Manufacturing processes of nonwoven fabric|
|Figure (2.2): Non woven technology|
2.2.1 Web formation:
There are a lot of methods to form a web like:
- Dry laid.
- Card laid.
- Air laid.
- Spun melt laid: Like (spun laid- melt laid)
- Wet laid.
- Other technologies: Like (electro static spinning-flash spun)
Web bonding is chosen according to the end use and followed applications. So, there are many types of bonding like:
- Stitch /bonding.
The opportunity to combine different raw materials and different techniques accounts for the diversity of the industry and its products. This diversity is enhanced by the ability to engineer nonwovens to have specific properties and to perform specific tasks .