About Thermal Bonded Nonwoven:

• In thermal bonding, the controlled heat is applied for bonding the non-woven fabrics. In addition, this type of bonding is applied to raw materials, which are thermoplastic (for e.g. polypropylene, polyester chips etc.) in nature.
• Here a low melt fibre or bicomponent fibre is introduced at the web formation stage to perform the binding function later in the process but the web fibre itself can be used.
• There are several thermal bonding systems in use:
• Calendar bonding
• Through-air thermal bonding
• Drum and blanket systems
• Sonic bonding
• In thermal bonding, heat energy is being used to stimulate an adhesive, which in turn flows to thermoplastic fibre juncture and interlocks the fibres upon cooling. The bonding agent may be individual fibres portions of individual fibres, or powders. Advantages of thermal bonding comprise low cost and the wide accessibility of binder materials and machines. Recently the use of thermal bonding is more popular than chemical bonding for medium weight nonwovens production.
• Thermal bonding is achieved as the result of a sequence of three events:
• Heating or heating,
• Flowing, and
• Cooling
• Three basic methods of heating or drying are used for thermal bonding: conduction, radiation, and convection.
• Conduction: is the transfer of energy between objects that are in physical contact. Here direct contact heating is done with heated calendar rolls. For area or surface glazing, smooth rolls are used. For point bonding, patterned or embossed rolls are used. Thermal calendaring is most efficient in terms of heat loss, but heavy roll pressures tend to destroy fabric loft.
• Radiation: is the transfer of energy to or from a body by means of the emission or absorption of electromagnetic radiation. For lofty or thick structures, this effect yields a bond intensity gradient throughout the fabric thickness. Radiant heating systems are used mostly for applications, which require instant heating and concentrated heating zones.
• Convection: is the transfer of energy between an object and its environment, due to fluid motion. Convection heating methods pass heated air through the nonwoven web and are used to bond many medium and heavy weight nonwovens. Two common commercial configurations are multizone through-air ovens and compact through-air ovens.

Advantage of Thermal Bonding over other web bonding:

• From an energy point of view, modern thermal bonding requires no heat for water elimination, which is very proficient.
• Production lines for thermal-bonded nonwovens also require less floor space & operator. Also the production rates of fabric production are very high.
• Thermal-bonded nonwovens are usually softer and drier, have superior strength per unit weight, and are permeable and absorbent for the reason that of very smaller bonding points.

Characteristics of Spunbond fabrics are:
The desired characteristics of Spunbond nonwoven fabrics are:

• Burst strengths,
• Elongation-to-break,
• Porosity and
• Stability to heat and chemicals
• Tear,
• Tensile,
• Thickness,
• Gram per square meter (GSM) range from 10 to 150

Raw materials

Application of Thermal Bonded nonwoven fabrics:

• Sanitary and Hygiene:
• Sanitary napkins,
• Baby diapers and
• Incontinence diapers

• Medical and Surgical:
• Gowns,
• Face masks,
• Caps,
• Drapes, etc

• Other Miscellaneous Applications:
• Filtration Material,
• Agriculture,
• Headliners, etc