About Needle-Punch Nonwoven

Needle punching is the oldest method of producing nonwoven products. The web for needle punch nonwoven is made with the help of dry-laid technology mainly by carding process. This process involves forcibly entangling layers of loose staple fibres or filaments into a 3-D structure by alternately punching and pulling out beds of barbed needles. With needle punching or mechanical bonding, strong yet flexible and comparably thick nonwovens are produced.
The needle punch is manufactured based on a two-step process:

• From granules to fibres: Polymer resin is extruded into endless fibres, and then stretched, crimped and cut into short fibres.
• From fibres to nonwovens: In this case fibres are carded and needle punched and then bonded thermally to form the ultimate nonwoven fabrics.

Characteristics of the needle punch web:

The Needle punch webs offer a wide range of product characteristics such as:

• Unique physical properties i.e., elongation in the X, Y & Z direction for mould-able applications,
• Ability to attach layers of different type fibre webs to produce composites,
• High opacity per unit area,
• High strength makes them overwhelming choice for geotextile fabric

Characteristics of the needle punch web:

The desired needle-punched fabrics characteristics are:

• Excellent puncture and penetration resistance
• High interface friction angles
• Thickness ensures long-term filter stability
• High water permeability
• High abrasion resistance
• Weights range from 70 g/m² to 1200 g/m².

Process Description:

Needle-punched nonwovens are manufactured by mechanically orienting and interlocking the fibers of a carded web. This mechanical interlocking is achieved with thousands of barbed felting needles repeatedly passing into and out of the web. The major components of the needle punch line and brief description of each are as follows:

• Blender - The machine is where the raw materials are stored at a desired proportion of different types fibers (e.g., 40% PP and 60% PET)

• Opener - It is where the raw materials are fed from the blender in order to reduce the size of fiber tufts from the blender to the hopper feed.

• Hopper - The machine where the fibers are stored and are transferred for fiber carding.

• Carding : The process where the entangled fibers are arranged into a parallel fibrous web.

• Cross Lapper - The machine that continuously lays a web so that its fibers are oriented in cross direction. The web is laid on the conveyor moving at right angles.

• Needle Punching - The process in which the web is bonded mechanically to each other by a series of needles. The designs of products are being controlled in this line. The operations consist of a pre-needler, drafter and a finish needle loom.

• Calendering - In this process a smoother product by heating up to a certain (melting) temperature depending on the raw materials used.

• Winding & Cutting - The final product is being wound into rolls and being cut into a specified width in this line.

Application of needle-punch nonwoven fabrics:

The major Application and End-usages of needle punch fabrics are:

• Geotextiles :
  Needle punch geotextiles are used in functions like

• Separation,
• Filtration,
• Reinforcement,
• Drainage & erosion control and
• Find applications in roads, railways, air runways, coastal shore protection, etc.
• Needle punch carpets: They are used in passenger cars as flooring material.
• Other Miscellaneous Applications :
• Headliners,
• Filtration,
• Insulation Felts, etc.