2. Alternative Techniques of Joining Materials
To join the fabric, the sewing process is done by using a needle and sewing
thread. It is the oldest and widely used method in the readymade garments
industry. But there are some fabric joining process comes by researching with a
long time though those have some limitations such as sea appearance, joining
speed, seam performance, etc. In case of some special cases, those alternative
methods have to apply for fabric joining instead of the normal sewing method.
Types of alternative methods of fabric joining:
Fusing
Welding
Adhesives
Molding
3. Fusing
It is the most used method among the four alternative fabric joining methods.
Normally it is used to attach interlining. Here, firstly the part of apparel that
is to be fused spread, and then the resonated interlining surface is placed on
it. Finally required pressure and temperature applied here smoothly. Resin on
the coating of interlining is melted by heat into the fabric under pressure.
When it becomes cool and hard both the fabric and interlining are attached.
4. Welding
In this method, fabrics are joined in a limited quantity. By using these types of
methods, two or more fabric plies which have made of at least 65%
thermoplastic fibers can be attached by providing heat and pressure along
the seam line.
Here, heat is generated by the ultrasonic process. By generating heat, the
thermoplastic fibers in the fabrics are melted and the melted polymers are
joined by applying required pressure. In this method, the transducer is used to
transfer electricity into vibration which is about 20000 Hz per second.
5. Adhesives
Adhesive means a substance that causes fibers, yarns, fabrics, or other
materials to adhere or stick together. There are two types of adhesive
available for joining the fabrics. Those are-
By using a silicon paper, containing a thin layer of adhesive in which
fabrics are joined after placing.
By using a solid adhesive, this will be melted under heat. As result
fabrics are joined together.
6. Molding
By using this method, one or more plies of fabrics cannot be joined
though it is placed as an alternative method of fabric join. Molding
helps to give a specific shape to the garments without creating
any seam. The shape is given to the fabrics by stretching or shrinking
and the entered thermoplastic fibers are softening by applying heat.
After that temperature is decreased to be normal. As a result, the new
shape or area of fabrics are made. It is done in the case of knitted
fabrics because it is easy to stretch or shrink the fabrics.
Fabric placed on a mold
Heat is applied (in a chamber)
Pressure is applied
Cooling
Achieving permanent shape
8. Principle of ultrasonic welding
In ultrasonic welding, high-frequency mechanical vibrations are
transferred to the parts to be joined, which cause sliding one part over
another. The joining occurs as a result of heat generated by friction and
severe plastic deformation.
In ultrasonic welding, frictional heat produced by the ultrasonic waves
and force is used for the joining process. Ultrasonic waves (15 to 60 khz)
are transferred to the material under pressure with a sonometer.
Welding times are lower than 3 s. The welding can proceed with or
without the application of external heat
9.
10. Limitations Alternative Techniques of Joining Materials
Lower joining speed hence less production.
Seam appearance is not so good.
Seam performance is not satisfactory in some aspects compared
to sewn seam.
Alternation of seam is quite difficult, also impossible in most of
the cases.
Comparatively less comfortable due to harsh feeling.
