Non woven fabric boast some specific characteristics including but not limited to absorbency, strength, liquid repellency, resilience, softness, flame retardance, washability, cushioning, filtering, bacterial barrier, and sterility. These distinct properties are often combined to create fabrics suited for a broad spectrum of applications for specific jobs and deliver high performance across a wide range of applications. One can be surprised at so many ways one's daily life is touched by nonwoven fabrics. Nonwoven fabrics have been extensively used in innumerable customer and industrial products, including absorbent hygiene products, apparel, home furnishings, healthcare, and surgical fabrics, construction, filtration, and engineering. Synwin non woven manufacturer will introduce the types of non woven fabric.
The Different Types of Non woven Fabrics
Nonwoven fabrics have long become an independent and technically sophisticated industry in its own right, and owe the prosperity of the industry to a great multiplicity of raw materials and process options. Nonwoven fabrics can be variously categorized by different classification methods. According to the practices of their production, nonwoven fabrics can be divided into a total of eight types.
1. Spunlacenon woven products
Spunlace non woven fabric is an essential type of nonwoven fabric. Spunlace nonwoven fabrics may sound unfamiliar, but indeed, products made from such spunlace nonwoven fabrics are widely used such as wet wipes.
The spunlace process, also known as hydroentanglement, is a manufacturing system for nonwoven fabrics that employs jets of water to entangle fibers and thereby provide fabric integrity. The spunlace process is free from binders and hence is ecologically harmless. Nonwoven fabrics manufactured with this process can maintain their original characteristics. The fiber is not damaged, and the appearance is closer to traditional textiles than other types of nonwoven fabrics. Spunlace nonwoven fabrics feature high strength, less fluff, good absorbability and permeability, softness and washability.
2. Heat-bonded non woven products
Heat bonding can be performed in a few ways with different types of heating methods. In through-air bonding, hot fluid or air is forced through a preformed web. When the temperature of the fluid or the air is high enough, the fibers partially melt and form bonds where they come into contact. In infrared bonding, infrared light provides the heat required to melt the fibers partially. In ultrasonic bonding, friction between fibers causes partial melting of the fibers. In thermal point bonding, the preformed fiber web passes between heated calender rolls that are either smooth or embossed with a bonding pattern. On a smooth calender roll, bonding occurs wherever fibers cross each other, while on an embossed calendar roll, bonding occurs primarily between the raised areas. In all the processes mentioned above, the fundamental working principle is the same - the fibers are heated, bonded, and then cooled.
Heat bonding is suited for manufacturing nonwoven fabrics with thermoplastic fibers with a low melting temperature including homofil and bicomponent fibers, allowing a wide range of fabric properties and aesthetic to be obtained to satisfy a broad spectrum of needs. Heat bonding is much less energy-intensive, kinder to the environment, and more economical. Effective thermal contact offers significant energy and water conservation in contrast to latex bonding. It is more environmentally friendly as there are no remainders to be treated.
3. Air-laid non woven products
Air-laid refers to a manufacturing technology that produces a web from short fibers by air. Separately loosened fibers and fine particles are uniformly dispersed in an airstream and laid on a metal mesh for bonding. Air-laid nonwoven technology generally uses latex emulsions, thermoplastic fibers, or some combination of both to bond the web’s fibers and increase the strength and integrity of the sheet. The process yields a paper-like fabric that is thicker, softer and absorbent. Air-laid nonwoven fabrics also boast more excellent tear resistance and tensile strength, particularly when wet. These physical characteristics of air-laid nonwoven fabrics make them suitable for many disposable absorbent applications in consumer, industrial, and institutional sectors such as household cleaning wipes and mops, adult incontinence products, and baby diapers.
4. Wet-laid non woven products
The working principle of wet-laying is generally like paper manufacturing. The difference lies in the number of types of synthetic fibers present in wet-laid nonwoven fabrics. A dilute slurry of water and fibers is deposited on a moving wire screen and drained to form a web. The web is further dewatered, consolidated, by pressing between rollers, and dried. Impregnation with binders is often included in a later stage of the process. The strength of the randomly oriented web is somewhat similar in all directions in the plane of the fabric. A wide range of natural, mineral, synthetic and human-made fibers of varying lengths can be used for the wet-laying process.
5. Spunbondnon woven fabric
Spunbond fabrics are produced by depositing extruded, spun filaments onto a collecting belt in a uniform random manner followed by bonding the fibers. The materials for making nonwoven fabrics by using spunbond techniques are mainly terylene and polypropylene. The fibers are separated during the web laying process by air jets or electrostatic charges. The collecting surface is usually perforated to prevent the air stream from deflecting and carrying the fibers in an uncontrolled manner. Bonding imparts strength and integrity to the web by applying heated rolls or hot needles to partially melt the polymer and fuse the fibers. Since molecular orientation increases the melting point, fibers that are not highly drawn can be used as thermal binding fibers. Spunbond nonwoven fabrics can be seen in carpet backing, geotextiles, and disposable medical and hygiene products. Since the fabric production is combined with fiber production, the process is generally more economical than when using staple fiber to make nonwoven fabrics.
6. Meltblownnon woven products
Meltblown technology is one of the most effective ways to make very fine, highly efficient filter media. The raw material is usually a thermoplastic synthetic material which is melted and forced through an extruder consisting of a very large number of tiny nozzles. Immediately after exiting the nozzles, the individual molten filaments are blown by hot air in the same direction while still in their semi-melted state, extending them and creating very fine, endless fibers, within a few milliseconds. A meltblown fiber has a diameter of less than 10µm, many times finer than a human hair, which has a diameter of 120µm.
7. Needle-punched non woven fabrics products
Needle-punched nonwoven fabrics are made where fibers are bonded together mechanically with fiber entanglement and frictions imparted by repeated penetration of fine needle barbs. Needle-punched fabrics have characteristic periodicities in their structural architecture that result from the interaction of fibers with the needle barbs. Fiber segments are reorientated and migrated from the surface of the web towards the interior of the fabric, forming pillars of fiber orientated almost perpendicular to the plane.
8. Stitch-bonded non woven fabric
Stitch bonding uses a cross-laid web, which is fed directly to the stitch bonder in a continuous process. The machine used in stitched bonding is basically a variation of a warp knitting machine, which bonds the fabric by knitting columns of stitches down the length of the web.
In some cases, the web is fed initially to a needle puncher to achieve a light needling operation, known as tacking, before the rolls of fleece are passed to a stitched board. Tacking enables the fleece to unroll easily and improves the mechanical interlocking between the fibers, which aims to provide sufficient anchorage of the fiber in the fleece. Other steps minimize this weakness include the use of fibers of longer staple length and the inclusion of some relatively low melting point fibers, which can provide additional bonding during subsequent heat setting.