Garment manufacturing does not end when fabric is cut and stitched. Dyeing and finishing operations are greatly influencing the appearance, feel and performance of the product during manufacturing. The ownership of fabric performance is often the more important part of interest, but these wet and chemical processes can have a powerful impact on sewing thread too. Variations in thread strength, colour, shrink, resistance to abrasion and surface properties can have a final effect upon a seam’s quality and garment’s durability.
An awareness of the impact dyeing and finishing has on sewing thread will allow manufacturers to choose thread construction to make sure garment seams will hold all the time.
Dyeing Can Change Thread Strength
The garment while undergoing the dye process is subjected to water, heat, dye, salt, alkali and other chemicals during the dyeing process. These factors may impact the physical characteristics of sewing threads, especially if the thread is not engineered for passing through the process.
The resistance to rupture, or thread tenacity, may be decreased for some thread constructions by high heat exposure or extended chemical exposure. The thread that is strong and good for sewing can become weaker following the dyeing process. That is especially relevant for garments that have high seam stress, like work wear, denim, uniforms and sportswear.
For this reason, not only the sewing performance but also the entire dyeing cycle should be taken into account when choosing a suitable thread for sewing.
Thread Shrinkage and Seam Appearance
Fabric and thread may have different reactions to heat and moisture. If the thread is prone to a large amount of shrink, it can result in puckered, distorted seams or sizing.
Sometimes, control of thread shrinkage is desirable, since it ensures that the thread keeps the seams from falling apart. But if there’s excessive or uneven shrinking, it will leave noticeable flaws in the vehicle.
Various manufacturers should thus consider thread shrinkage, along with fabric shrinkage, when designing clothing materials that often go into fabric dyeing or intensive finishing processes.
Colour Fastness Matters
If the garments are dyed after stitching, there can be additional absorption or reactions that take place between the dye and the sewing thread. It may be desirable when a consistent colour is desired, as is the case in garments dyed as fashion products.
The colour must have proper dyestick property and colourfastness to the thread, however. Low colourfastness may cause fading, bleeding or toned colours which may cause difference in colours during washing and use.
With special-made threads for garment dyeing, the dyeing area will have a more uniform colour, while the desired characteristics will be retained.
Finishing Chemicals Can Affect Thread Performance
Garment finishing may include such actions as softening, resin treatment, enzyme washing, bleaching, water repellency and special texture. Different chemical and mechanical conditions can be present in each of the processes that can expose the thread.
Mechanical abrasion, for instance by enzyme or stone washing, can enhance and colour removal by bleaching can impair thread strength. Surface properties of the surface of thread can also be changed by some of the finishing chemicals, which may affect the lubrication and seam properties.
If the finishing method is a lot more vigorous, then it’s even more vital to use a thread which has been tested under such extreme closure conditions.
Heat Treatment and Drying
Recovering sewing threads can be exposed to high temperatures during the drying and heat-setting process. Excessive heat has the ability to affect thread strength, elongation, shrinkage and lubrication.
However, synthetic threads (usually recycled polyester thread) are resistant to heat and moisture, with the level of resistance varying depending on the polymer, construction, finishing and temperature.
The control of drying and heat-setting parameters minimises the needless stress of fabrics and sewing thread.
Mechanical Finishing Can Increase Abrasion
Seam areas may be exposed to repeated bending, rubbing, stretching and impact during the washing and finishing processes. Stone washing, mechanical softening, or other processes can therefore generate even more abrasion proximal to areas in which the stone was stitched.
In garments that are designed to have intense fining, the abrasion resistance and tenacity of the thread must be in line. Core spun (polyester corespun thread) and other engineered thread constructions can offer a blend of strength, sewability and abrasion resistance.
Testing Before Production
The simplest approach to steer clear of thread-related issues is to test out the whole garment procedure prior to beginning mass creation. Although it is only common to check the thread in its own condition, a manufacturer should test it after dyeing, washing, drying and finishing.
These are just a few important checks that can be done:
- Seam strength after processing
- Thread colourfastness
- Thread shrinkage
- Abrasion resistance
- Seam appearance and puckering
- Breakage of the thread while sewing
- Chemical and heatproof
This enables the solution of any problem at an early stage, without it escalating to an expensive defect in the production run.
Choosing the Right Thread for the Process
No single sewing thread is perfect for all of the garment dyeing and finishing processes. Fabric, stitch, machine parameters, dye chemistry, laundering process, washing temperature, finishing chemicals, and performance requirements of the garment should all be taken into account in the selection of threads.
If necessary for a high-demanding application, manufacturers should perform tests in the embroidery process and determine the appropriate sewing parameters together with the supplier of the threads.
Conclusion
Sewing thread performance may be greatly affected by the garment dye and/or finishing. Thread strength, colour, shrinkage and the appearance of the seams may vary with heat, moisture, chemicals, mechanical abrasion and drying. It may also be that they only choose the thread based on its sewing performance and subsequently end up with sewing issues during production.
Manufacturers can use this evaluation as they navigate the entire garment manufacturing process to produce longer-lasting stuff, fewer defects, and enhanced looks.
