1. Introduction
In recent years, knitted fabrics have gained prominence in contemporary fashion. Their applications now extend from casual everyday clothing to garments designed for sports and injury recovery. Due to their high extensibility and smooth, flowing lines, knitted structures provide a second-skin effect that does not restrict movement. Consequently, knitted fabrics are commonly used in the production of T-shirts, polo shirts, leggings, and sportswear. Their structural adaptability also makes them well suited to designs and treatments that emphasize fashion over fabric [1].
A widely used effect in the fashion industry is the distressed or "destroyed" appearance, which imparts a worn or antique look to garments. Traditionally, such effects have been achieved through techniques including sandblasting, acid washing, stone washing, and mechanical abrasion. However, several studies have indicated that while these methods effectively produce an aged appearance, they also pose significant environmental and occupational health risks. These risks include the release of chemical toxins into water, excessive water consumption, dust emissions, and unsafe living conditions [1]-[4]. As a result, environmentally friendly alternatives to these processes have become a major focus in textile engineering and fashion technology [5].
In recent years, CO2 laser technology has emerged as a potential non-contact, digitally regulated method for textile surface treatment [6] [7]. Previous studies have demonstrated that CO2 laser finishing techniques can effectively replicate traditional damage on denim while achieving significant savings in water, chemical, and energy consumption [8]. However, most research has concentrated on woven fabrics, as denim remains the most treated substrate, with limited attention given to the application of laser technology on knitted products [9] [10]. Knitted structures, characterized by their loop-shaped geometry, higher porosity, and elastic recovery, respond differently to thermal and photonic energy compared to woven textiles [11]. These differences can impact surface morphology, coloration, shrinkage patterns, and fastness.
The objective of this research is to systematically explore the feasibility of using CO2 laser treatment to produce controlled distressed effects on selected knitted structures without compromising their functional performance [1] [3] [6] [12]-[20]. This study aims to evaluate the aesthetic appeal, physical properties (surface characterization), and post-wash durability of laser-treated knitted fabrics. It will also compare different knit structures subjected to identical laser settings and investigate the ecological benefits of this technique as an alternative to conventional distressing methods [4] [9] [15] [21]. By addressing this gap, this research provides both practical and scientific insights into the development of environmentally friendly garment finishing processes that strike the right balance between visual aesthetics, fabric integrity, and minimal environmental impact.
2. Methodology
2.1. Materials
In this research paper, we have selected a total of thirteen knit fabric samples of different types in order to assess the CO2 laser outcomes on both aesthetics and durability. These fabrics are regularly utilized in the garment sector to manufacture garments, such as but not limited to t-shirts, pants, and so on. Fabric samples were used, and their respective (GSM) values, which are the weight of the fabric and its density, are given below:
a) Single Jersey (180 GSM) (Figure 1)
b) Heavy Jersey (170 GSM) (Figure 2)
c) 2 × 2 Rib (300 GSM) (Figure 3)
d) 4 × 2 Lycra Rib (200 GSM) (Figure 4)
e) Design Rib (400 GSM) (Figure 5)
f) Mesh (180 GSM) (Figure 6)
g) Pique (210 GSM) (Figure 7)
h) Interlock (330 GSM) (Figure 8)
i) Design Fabric (240 GSM) (Figure 9)
j) Ponte Fabric (280 GSM) (Figure 10)
k) Waffle (320 GSM) (Figure 11)
l) Fleece (300 GSM) (Figure 12)
m) French terry (280 GSM) (Figure 13)
Such pieces of fabric were obtained from one of the textile factories, where they received washing services after laser treatment. Various types of fabrics were selected to offer a wide range of outcomes regarding feel and extent of wear during laser distressing.
Figure 1. Single jersey fabric.
Figure 2. Heavy jersey fabric.
Figure 3. 2 × 2 rib fabric.
Figure 4. 4 × 2 lycra rib fabric.
Figure 5. Design of rib fabric.
Figure 6. Mesh fabric.
Figure 7. Pique fabric.
Figure 8. Interlock fabric.
Figure 9. Design fabric.
Figure 10. Ponte fabric.
Figure 11. Waffle fabric.
Figure 12. Fleece fabric.
Figure 13. French terry fabric (Before wash).
2.2. Equipment
The laser treatment was performed using the JEANOLOGIA Laser System: a CO2 laser machine that is commonly used in the textile industry to modify the surface [22]. The system is used with the high specification CO2 RF Metal Lasers in the following way:
a) Laser Power: Average of 600 W, maximum of 1800 W
b) Working Area: 1500 mm × 1500 mm
c) Wavelength: 9 - 12 µm
d) Positioning Accuracy: ±0.1 mm
e) Cooling System: Chiller System
The JEANOLOGIA laser decouples the high-accuracy topographical alterations on textile without destroying bulk characteristics, which in this manner has a less adverse effect on the mechanical and photochemical degradation of fabrics. The capability of this machine to provide a high degree of control in terms of the heat input on the fabric is also relevant to the provision of appealing aesthetic effects with a relatively minimal amount of damage to the integrity of the fabric overall.
2.3. Laser Treatment Procedure
In this technology, laser treatment is carried out using a laser to ensure that the surface properties of the materials are altered by melting or vaporizing the material, using the focused light source (e.g., an improved laser). A distressed look in knit fabric samples was acquired with a laser in the current work. The exposure time of the laser was well controlled because each piece of fabric was not exposed to the treatment for more than 2 s. The intensity of the laser power was absorbed on the surface of a piece of fabric, vaporizing and melting locally so as to achieve a special aesthetic effect. Laser treatment is also chosen over traditional abrasive methods, such as sand blasting or chemical etching, due to its gentle impact on the environment and extremely low chances of damaging the garments.
The thought was to understand the response of each fabric to the heat of the laser, and whether she could manage to create an unpleasant effect without excessive weakening of the fabric. The other goal was to test the feasibility of laser use in the trim fabric sector, which was previously dominated by manual acidic killing techniques.
2.4. Washing Process
The French terry fabric sample that resulted from the improved performance using the laser process was chosen to be further investigated by washing. The wear and appearance of the laser-treated cloth were intended to be tested after washing. A Miele washing machine (Germany) was used under the following conditions:
a) Liquor Ratio: 1:10 (fabric-to-water ratio)
b) Wash Ingredients:
i. Hydrogen Peroxide (H2O2, Figure 14): 1.5 g/l
ii. Caustic: 1.5 g/l
iii. Detergent: 0.5 g/l
iv. Stabilizer: 0.5 g/l
c) Temperature: 90˚C
d) Wash Time: 20 minutes
Figure 14. Chemical structure of Hydrogen Peroxide (H2O2) [23].
The washing procedure was formulated to reflect general post-treatment patterns in the textile sector. Hot water wash and cold-water wash were conducted after washing and tumble drying of the fabrics. This test was performed with the aim of determining whether or not a fabric that was treated with the laser would preserve its structural integrity and/or design effect when subjected to regular laundering.
2.5. Shrinkage Test
The shrinkage test was performed to assess whether the laser treatment and washing process caused any significant dimensional changes in the fabric. The following steps were taken:
i. The pre-wash measurement of the French terry fabric was recorded as 20 cm.
ii. After washing, the post-wash measurement was taken, and the shrinkage percentage was calculated using the formula:
Shrinkage Percentage = [(Before wash measurement − After wash measurement)/Before wash measurement] × 100
a) Pre-Wash Measurement: 20 cm
b) Post-Wash Measurement: 19.5 cm
c) Shrinkage: 2.5%
The shrinkage observed (2.5%) was well within the acceptable range for most commercial fabrics, where a maximum shrinkage of 5% is typically considered acceptable.
3. Data Analysis
Aesthetic assessment of every fabric was done through naked eyes also after lasing and washing had been done. The aim of the research, though, was pegged on whether the laser distressing 10 effect was even and acceptable using the varied knit fabrics. The properties of strength of fabric were also tested, which include slippage of the yarn and durability of the fabric after treatment.
It was observed that a good number of the fabric samples did not react well or rather reacted anew; French terry sustained an equal measure of distressing with a small amount of fraying (Figure 15). The cloth did not lose its strength, form, and appearance following washing and would be applicable to additional applications in fashion designing/the clothing industry.
Figure 15. French terry fabric (After washing) [2].
4. Results and Discussion
4.1. Laser Treatment on Knit Fabrics
A difference in outcome was observed in the treatment of the thirteen fabric samples with the CO2 laser. The aim of the laser process was to achieve a destroyed or distressed appearance that is popular in the fashion industry for creating clothes that look old and worn. It was also established that among the fabrics sampled, French terry fabrics were the most useful when it came to laser distressing because most of the samples gave poor results despite being in the majority.
French Terrycloth—This came out best. The distressing caused by the laser was controlled, and it looked good. French terry also did not unravel to a great extent as the yarns did but remained in good condition during distress, unlike other types of fabric. The processing of the fabric did not compromise its strength, and it showed a smooth surface finish. The fabric had been preserved even after washing, but it appeared slightly modified, not heavily damaged, and did not lose its color. This renders knitted French terry a good candidate for fashion design since the aesthetic properties and utilitarian functions of a fine finishing cloth were maintained. Other Fabrics The remaining fabric samples, i.e., Single Jersey, Heavy Jersey, and 2 × 2 Rib, appeared to be in different forms of damage. But in the main, that scalded too far away and left irregular fraying or weakened the cloth. As an example, when Pique and Mesh fabrics were subjected to damage, they became unusable (which implies that not all fabrics can be subjected to laser treatment as efficiently). This concurs with other publications that have reported structures and the composition of fabrics to be a critical bias factor to their distressing with laser.
4.2. Impact of Laser Treatment on Fabric Durability
CO2 laser treatment process provides local heat to the fabric, which is converted to solid-liquid-gas transformation. The resulting effects are the desired appearance effects, but the strength of the fabric and its durability are causes of concern.
Shrinkage: The test on the shrinkage of the French terry fabric was conducted following the laser treatment and washing. The cloth had a contraction of 2.5%, which is reasonable in textile machinery, and a maximum shrinkage of 5 percent can be obtained. In other words, laser treatment did not appear to affect the dimensional stability of the fabric post-washing in a negative way.
Fabric Strength: The strength of the fabric after it was distressed with laser was determined by observing the slippage of the yarns in different directions on the plane of the fabric. It was found that some unraveling was towards course-wise, but none unraveled towards wales-wise. This implies that the architecture of the French terry was mostly retained in some of the directions by the laser-treated fabric, which is critical in the tensile properties and durability of garments.
4.3. Environmental Impact and Sustainability
CO2 laser technology (environmentally friendly) Above all, the CO2 technology of laser technology has numerous environmental advantages over other fabric treatments like sandblasting and acid washing, which also result in by-products that are both environmentally hazardous, such as toxic fumes and millions of pounds of waste. The CO2 laser procedure does not create any chemical waste and is a relatively green procedure as far as the environment is concerned. The precision and efficiency of the laser similarly reduce the overall quantity of energy consumed during distressing, which is a more eco-friendly option for the textile industry [24]-[27].
5. Conclusions
It has been revealed in this research that CO2 laser treatment is a green and new technology used in distressing knit fabrics. When an experiment was conducted to test the impact of such laser technology on various cloths, significant differences were discovered between the results. Among the 13 samples of fabric that were tested, French terry was identified as the most appropriate fabric that could be laser distressed in terms of aesthetic appearance, low shrinkage, and good fabric durability post-treatment.
It was discovered that CO2 laser ablation is a cost-effective technique of controlled distressing and is better than other techniques such as sandblasting, acid washing, and hand sanding methods, which are less precise and also have a negative impact on the environment. French Terry, even when washed, would not have its remaining power and appearance revealed by damaging the fabric structure adequately with the laser material during the treatment.
To make the fabrics durable, the laser treatment did not result in any severe shrinkage of the French terry fabrics, which had an attractive percentage of 2.5% at maximum, which was less than the required percentage to make commercial garments. Also, the fabric strength was significantly maintained with minimal tension of backbone destruction in the course wise direction, therefore proving further that laser could be used to maintain the fabric integrity.
Such findings have great industry application, particularly in the textile and sustainable fashion industry. Findings have shown that CO2 laser could be a viable substitute for chemical or traditional distressing, which will assist the industry not only in minimizing its effects on the environment but also in advancing the quality of fabric finishes. Laser may also reduce the level of noxious emissions as well as water usage, which are required by the new trends of ecological manufacturing in the textile industry. Future research would consider the maximization of the laser settings with various fabric types to expand the range of applications throughout the textile sector.
Overall, the CO2 laser represents a prospective technique for distressing fabric in a stable and sustainable way. The accuracy and the fact that it does not cause significant environmental damage, coupled with the delicate manner in which it maintains the integrity of garments, make it a tremendous instrument in contemporary clothes manufacturing, as fashion designs will not only be extra-long lasting but also stylish.
Acknowledgements
This research was conducted without any financial support from funding agencies in the public, commercial, or not-for-profit sectors.