Study on the Effect of Terminalia chebula Softening Treatment on Physical and Mechanical Properties of the Banana Fabric

ABSTRACT

The demand for environmentally friendly clothing and fabrics continues to increase globally. Banana fiber is a sustainable fiber known for its high tensile strength. It can be effectively blended with cotton and various synthetic fibers to develop versatile fabrics. The fiber’s abrasive texture is a major problem, making it difficult to wear and limiting its application in the apparel industry. The study focuses on the utilization of Terminalia chebula, an organic material, as a softening agent to address these concerns and maintain the environmentally friendly nature of the banana fabric. The experiment involved treating the banana fabric with different concentrations (20%, 40%, and 60%) of Terminalia chebula solution. The physical, comfort, and mechanical properties of the treated fabric are evaluated and compared to those of the untreated fabric. The results demonstrate that Terminalia chebula treated fabric has better comfort (both bending rigidity and stiffness) Notably, the treated fabric shows a substantial improvement in crease recovery and drapability. However, no effective improvement was found in tensile and seam strength. In addition, the study explores the potential of T. chebula as a multifunctional textile finish, making a valuable contribution to the growth of sustainable and eco-friendly textile finishing methods.

摘要

全球对环保服装和面料的需求持续增加. 香蕉纤维是一种可持续的纤维，以其高抗拉强度而闻名. 它可以与棉花和各种合成纤维有效地混纺，开发出多功能织物. 纤维的磨料质地是一个主要问题，使其难以穿着，并限制了其在服装行业的应用. 这项研究的重点是利用有机材料车布拉Terminalia chebula作为柔软剂来解决这些问题，并保持香蕉织物的环保特性. 实验包括用不同浓度（20%、40%和60%）的车前子溶液处理香蕉织物. 评估处理过的织物的物理、舒适和机械性能，并将其与未处理的织物进行比较. 结果表明，经千叶处理的织物具有较好的舒适性（弯曲刚度和刚度）. 值得注意的是，经过处理的织物在折痕恢复和悬垂性方面表现出显著的改善. 然而，在拉伸和接缝强度方面没有发现有效的改善。此外，该研究还探索了T.chebula作为一种多功能纺织品整理剂的潜力，为可持续和环保的纺织品整理方法的发展做出了宝贵贡献.

KEYWORDS:

• Eco-friendly softener
• banana fabric
• Terminalia chebula
• mechanical properties
• physical properties

关键词:

• 环保柔软剂
• 香蕉织物
• 榄仁树
• 机械性能
• 物理特性

Introduction

In recent times, there has been a significant change within the textile industry for the adoption and implementation of sustainable production methods. In response to growing savvy consumers and their demand, textile manufacturers are progressively adopting environmentally sustainable practices to reduce the ecological footprint of their activities. The use of plant-based fibers is gaining traction as a sustainable strategy, supported by programs such as the United Nations’ Sustainable Development Goals (Khan et al. 2022).

Within the framework of sustainable alternatives, banana fiber emerges as a beneficent alternative. Banana agricultural leftover cellulosic fibers are being used as a renewable resource in the textile industry, paper industries and a reinforcement in composites because of their several advantageous properties, including excellent mechanical strength, moisture absorption, and antimicrobial properties (A. Kumar et al. 2013; Pappu et al. 2015). In addition to its exceptional properties, banana fibers possess nontoxic characteristics and decompose readily, which is in complete harmony with the principle of sustainability (Sharma and Kumar 2013).

The composition of banana pseudostems was analyzed, and the results are shown in Figure 1. The presence of lignin in the banana fiber structure makes it rigid and coarse, which can cause discomfort when used in garments that come into direct contact with the skin, unlike cotton or silk (Bilba, Arsene, and Ouensanga 2007; Vardhini et al. 2016). Treating with conventional chemical softeners not only impairs the quality of the fibers and yarns but also creates hazardous effluents, posing a threat to both human health and the environment. To achieve a sustainable approach, it is necessary for a shift toward natural treatments that can help minimize the negative impacts of chemicals and support ecological balance (Ezeamaku et al. 2022).

Figure 1. Banana fibre composition.

Additionally, banana fibers possess inherent properties that enable them to absorb moisture effectively. However, during humid conditions, the fabric may feel damp and become uncomfortable to wear, resulting in an unpleasant odour. Antimicrobial treatments contribute to the control of unpleasant odours, allowing fabrics to maintain their freshness for longer lengths of time between washes.

In response to the risks and environmental concerns associated with commercial softeners, there has been a growing interest in the development of natural-based alternatives for textile applications. Table 1 explores the utilization of diverse natural materials such as Citrullus colocynthis seed oil, epoxidized sesame oil, Gum from the Commiphora Africana tree and Sapindus emarginatus vhal (Soapnut) as textile softeners. The oil-based softeners face the challenge of achieving and maintaining emulsion stability in fabric softener development. Considering the challenges, this paper has come up with a novel approach of using Terminalia chebula for the softening treatment which also exhibits additional properties of antimicrobial and mordanting. Treating fabric with Terminalia chebula enables a multi-finishing effect thereby reducing the cost of using different finishes for various functional properties.

Table 1. Natural softeners and their evaluation methods.

Authors	Natural softener	Extraction methods	Application method	Evaluation methods	Description
Asmelash and Ayele 2021	Gum from Commiphora Africana tree	Sap is collected by axing the stem.	Pad dry cure method	Stiffness, crease recovery, and drapability of treated fabric samples compared with those treated with commercial softeners.	According to the study, natural gum from the Commiphora Africana tree can replace commercial softeners in textile finishing procedures and perform similarly in fabric characteristics.
Hoque et al. 2018	Sapindus emarginatus vhal (Soapnut)	Dried and powdered	Immersing in the solution bath	Fabric weight change, absorbency (immersion, drop, spot tests), mechanical properties (bursting strength, GSM, stitch density).	The study compared the effectiveness and cost of natural vs. synthetic detergent scouring, to assess performance, environmental impact, and economic feasibility.
Noor. et al. 2024	Citrullus colocynthis seed oil	Emulsify process	Pad-dry-cure method	Tensile testing, bending tests, and visual inspection. Antimicrobial efficacy against gram-negative and gram-positive bacteria.	Citrullus colocynthis seed oil improves fabric properties and offers eco-friendly finishing. However, maintaining emulsion stability is crucial for ensuring uniform dispersion of the softening agents onto the fabric.
Ortega-Toro et al. 2021	Epoxidized sesame oil	Epoxidation	Extrusion and compression moulding techniques	Moisture content, solubility, contact angle, tensile strength, elongation at break, modulus of elasticity, barrier properties, structural properties, and thermal analysis.	Epoxidized sesame oil enhances adhesion and thermal stability for semi-rigid food packaging. However, the selection of specific oils is often hindered by their high cost, making it challenging to achieve an effective cost-to-benefit ratio.
Ogorzałek et al. 2020	Hydrophobic supercritical CO2 raspberry seed extract.	Supercritical CO2 extraction technique	Fabric softener is added during the rinse cycle.	Turbidity, dynamic viscosity, fabric softness, fabric re-wettability. Structural analysis using microscopy techniques.	The hydrophobic extract changed the fabric softener’s structure, increasing turbidity and viscosity. The extract-enriched softness and reduced re-wettability.

Terminalia chebula (T. chebula), also known as black myrobalan, is a member of the Combretaceae family. In dry matter, T. chebula pulp consists of condensed saponins and tannins at 8.4% and 9.9%, respectively. The pulp can be used as an excellent natural dye and mordant (P. P. Singh and Sharma 2020). Tannins present in it serve as natural mordants resulting in bright color and possess antimicrobial properties (Nam and Lee 2014; Shabbir et al. 2016; A. Singh and Sheikh 2020).

T. chebula is known as “the king of Medicine” in Tibet because of its remarkable medicinal properties. It has been researched thoroughly for its potential applications in textile technology and healthcare. Researchers Bag et al. (2009), Kumar et al. (2012), and Rathinamoorthy et al. (2011) investigated the potential of T. chebula fruit extracts for developing special antibacterial finished fabrics. Moreover, the presence of tannins, phenols, and saponins in the treated fabric serves as sustainable alternatives for the environmental issues related to textile odours (Rathinamoorthy et al. 2014).

Based on previous studies, T. chebula serves as an alternative to traditional antimicrobial finishes and mordants. However, none of the earlier research used T. chebula as a softener. The study aims to present a novel approach of utilizing T. chebula as a softener and evaluate the physical and mechanical properties of banana fabric. Additionally, the research investigates the impact of varying concentrations of softener’s effect on the fabric's performance.

Materials and methods

Fabric preparation

The fabric samples employed in the study were plain weave banana yarn (weft) and cotton yarn (warp). Table 2 details the characteristics of the fabric.

Table 2. Fabric characteristics.

Property	Fabric specification
Grams Square Meters (g/m^2)	80
Weft yarn count (banana yarn)	47 Ne
Warp Yarn count (cotton yarn)	51 Ne
Ends Per Inch (EPI)	118
Picks Per Inch (PPI)	25

Preparation of Terminalia chebula extract and application

The fruits of Terminalia chebula used in the study were obtained from commercial outlets in Chennai, Tamil Nadu, India. The fruits were dried in a shaded area and ground into a fine powder. A 20% concentration solution was prepared by mixing 20 grams of powder with 100 ml of water and leaving it at room temperature for 24 hours. Similarly, solutions of T. chebula softener were prepared at 40% and 60% concentrations using the same method.

For the application, the weighted banana fabric was soaked in an open bath with a ratio of M:L at 1:30 and left for five hours. The processing was carried out at room temperature, after which the sample was rinsed with cool water and pad dried.

Testing methods

Presence of saponin: The saponin content of the T. chebula natural softener used in this study was validated by the foam test, which involved mixing the powder in a beaker with 100 ml of distilled water. The mixture was heated with continuous stirring at 30°–40°C on a hot plate for 20 minutes before filtering through filter paper. A test tube was filled with 5 ml of distilled water, and 1 ml of the extract was combined with the mixture while being vigorously shaken. The presence of saponin was inferred from the formation of a consistent froth.

Following the foam test, the treated and untreated fabric samples were tested for stiffness, crease recovery, drape ability, air permeability, tensile and seam strength to examine the effectiveness of the softener. The following tests were carried out:

The fabric samples were prepared to the standards mentioned in Table 3 and tests were conducted before and after softening treatment with T. chebula concentrations of 20%, 40% and 60%.

Table 3. Testing Instruments, standards, and sample measurements.

Testing	Instrument	Standard	Sample measurements
Fabric stiffness test	Shirley stiffness tester	ASTM D1388–2007	2.5 cm wide and 20 cm long (warp and weft)
Fabric thickness	Shirley thickness gauge	ASTM D1777–96 (2007)	The thickness is measured in mm at different places on the fabric.
Cease recovery	Shirley crease recovery tester	IS 4681:1981	2 inches long and 1 inch wide (warp and weft).
Drape ability	Drape meter	IS 8357:1877	15 cm radius.
Air permeability	Air permeability tester	BS 3321:1960	Test area of 5.07 cm^2
Tensile strength	Mechanical tensile strength tester	IS 9030:1979	3.6 cm long and 10 cm wide. (warp and weft)
Seam efficiency	Mechanical tensile strength tester	IS 9030:1979	3.6 cm long and 10 cm wide, stitched (lapped seam) leaving a 2 cm seam allowance. (warp and weft)

Results and discussion

Determination of weight gain

The weight of the fabric before and after softener treatment is presented in Table 4. After the softening treatment, a minimal variation in the GSM of the fabric was observed.

Table 4. GSM comparison between treated and untreated samples.

Fabric weight GSM(g/m^2)
Before treatment	After treatment
	20%	40%	60%
80	65	68	71

The above table shows that the weight of the fabric treated with 20%, 40% and 60% T. chebula seems to be effective in reducing fabric weight, indicating that some material is lost or redistributed during the softening process. This could be due to the removal of substances that contribute to the weight of the fabric and fabric shrinkage remarkably (Sarkar and Khalil 2014).

Determination of fabric stiffness

The fabric stiffness was determined based on three different tests, namely, bending length, bending modulus and bending rigidity. As observed in Table 5, the bending length for the untreated sample in the warp direction is 2.66 cm, while for the weft direction, it’s significantly higher at 5.375 cm. As the concentration of softener increases (20%, 40%, and 60%), there’s a consistent decrease in bending length for the warp way sample from 1.7 cm (20% conc.) to 1.4 cm (60% conc.) and weft way sample from 4.4 cm (20% conc.) to 3.1 cm (60% conc.). It was also noticed that the bending rigidity and modulus of the fabric decreased in a similar pattern. This implies that the application of a softener significantly improves the fabric’s flexibility and softness in both warp and weft directions. According to these results, treating fabrics with T. chebula softeners improves their feel and the comfort property of the fabric.

Table 5. Comparison of the bending length, rigidity, and modulus between treated and untreated samples.

Fabric stiffness parameters		Fabric Thickness (mm)	Bending Length (cm)	Bending Rigidity (mg cm)	Bending Modulus (kg/cm^2)
Untreated sample	Warp	0.29	2.66	150.56	74.07
	Weft		5.375	1238.8	609.52
20%	Warp	0.33	1.7	33.36	11.13
	Weft		4.4	580.54	193.85
40%	Warp	0.35	1.5	26.56	7.43
	Weft		4.2	522	146
60%	Warp	0.36	1.4	19.48	5.01
	Weft		3.1	227.24	58.44

Sonee and Pant (2014) conducted a study demonstrating that fabrics with lower stiffness parameters generally provide better softness. At increasing treatment levels, the reduction in stiffness becomes more noticeable, suggesting a dose-dependent relationship between the level of treatment and fabric softness. According to previous studies (T. Igarashi et al. 2016), the additive and adhesive properties of the softener reduce friction between the fibers in the fabric, results in decreasing bending length.

Determination of crease recovery and drapability

The drapability coefficient and crease recovery angle for the treated and untreated fabric samples are shown in Table 6. The tabulated values show the effect of gradually increasing the warp and weft way crease recovery angles. The crease recovery angle of the untreated sample was 143°, and the angle increased considerably upon applying softener (20% conc.) to 147°. As the softener concentration increased from 20% to 40%, the crease recovery angle of the fabric increased from 147° to 155°. Similarly, with an increase from 40% to 60% concentration, the crease recovery angle of the fabric increases to 163°, as shown in Table 6. Increasing crease recovery indicates that the softener-treated fabric acts as a cross-linking agent, improving crease recovery and fabric softness by reducing chain slippage of adjacent cellulose chains within the fabric structure (Talebpour and Holme 2006).

Table 6. Comparison of the crease recovery angle and drapability coefficient between treated and untreated samples.

	Before treatment	After Treatment
		20%	40%	60%
Crease Recovery angle (degree)	143	147	155	163
Drape coefficient (%)	80.85	75.76	67.5	60.6

From an aesthetic point of view, the draping ability of the fabric is an important property. Appropriate draping results in a smooth fabric that does not rip when stretched across a surface. The drape coefficient (F) defines the degree of drape. A lesser drape coefficient (F) value indicates better drapability and softer fabric. In other words, a more significant F value refers to a stiffer fabric.

The effect of softener on fabric drapability is shown in Table 6. The drape coefficient of the untreated fabric sample was 80.85% and at a 20% concentration of softener, the drape coefficient reduced to 75.76%. Increasing the concentrations of softeners to 40% and 60%, the drape coefficient further reduced to 67.5% and 60.6% respectively. Softeners work by lubricating their surface, reducing fiber-to-fiber friction. This reduction in friction leads to a smoother, softer fabric with improved flexibility and drapability, enhancing comfort and tactile appeal (Fan 2008).

Determination of air permeability

Table 7 indicates that the untreated sample shows an air permeability value of 5.9 cc/cm²/sec, when a 20% concentration of softener is applied, the fabric air permeability is reduced to 2.3 cc/cm²/sec. It is gradually seen that as the concentration increases from 40% to 60%, the air permeability reduces from 2.1 to 1.7 cc/cm²/sec. It is evident from the result that if the amount of softener is increased, then the air permeability of the fabric decreases.

Table 7. Air permeability comparison between treated and untreated samples.

Air permeability (cc/sec/cm^2)
Before treatment	After Treatment
	20%	40%	60%
5.9	2.3	2.1	1.7

The ability of a fabric to absorb moisture could have an impact on air permeability. Naturally, banana fibers are hydrophilic, and they readily absorb softener resulting in a change in the porosity and thickness of the softener-treated fabric (Al Belihy 2021).

Evaluation of fabric tension and seam strength

The fabric tensile strength and seam strength of untreated and treated samples are tabulated in Table 8. The untreated samples show better fabric tensile strength and seam strength when compared to the softener-treated samples. Increased concentrations of the treatment result in a decrease in tensile strength along the warp and weft directions from 44 kgf (untreated sample) to 30 kgf (treated with 60% conc.) and from 22 kgf (untreated sample) to 13 kgf (treated at 60% conc.) respectively. It has been observed that the material tends to be flexible on softening treatment which results in weakened material resistance to deformation accompanying a decrease in breaking strain. Previous research has also shown the correlation between a decrease in breaking strain and the use of softeners on cotton fabrics (Chattopadhyay and Vyas 2010; Cheng et al. 2009).

Table 8. Seam strength, fabric tensile strength and seam efficiency comparison between treated and untreated samples.

Fabric and seam Strength		Seam strength (kgf)	Fabric Tensile strength (kgf)	Seam efficiency (%)
Untreated samples
	Warp	25.5	44	57.9
	Weft	3.5	22	15.9
Treated samples
20%	Warp	15	38	39.4
	Weft	2.5	19.5	12.8
40%	Warp	11.5	32.5	35.3
	Weft	2	16.7	11.9
60%	Warp	9	30	30
	Weft	1.5	13	11.5

Seam efficiency is a valuable parameter that demonstrates seam performance as measured by the ratio of sewn and unsewn fabric strengths. As in Table 8, seam efficiency values of the fabrics decrease with increasing the concentration treatment similar to tensile strength. Applying a softening treatment, especially at higher concentrations, reduces seam efficiency from 57.9% (untreated) to 30% (treated at 60% conc.) and from 15.9% (untreated) to 11.5% (treated at 60% conc.) warp and weft directions respectively. Studies show that applying softeners to textiles reduces their seam strength, lowering their seam efficiency (İlleez, Dalbaşιi, and Kayseri 2017).

Conclusion

The study explored the potential sustainable benefits of utilizing Terminalia chebula as an alternative to conventional textile softeners. Results from foam testing and comparisons of GSM values before and after treatment have confirmed the presence of softening properties in T. chebula. Additionally, examining the decrease in air permeability and the increase in fabric thickness supports the softener’s absorption by the fabric. As indicated by the study, the softener absorption by the fabric has reduced the porosity of the fabric, as the permeability value of the fabric decreases substantially with increasing concentration from 2.3 cc/sec/cm2 (20% conc.) to 1.7 cc/sec/cm2 (60% conc.).

In comparison to untreated banana fabric, the fabric treated with T. chebula showed better physical, comfort, and functional performance. The results show that by increasing the concentration of T. chebula softener from 20% to 60%, the drape coefficient and bending length of the fabric decrease. It is observed that the drape coefficient decreased from 80.85% (untreated fabric) to 60.6% (treated with 60% conc.) and the bending length of the fabric from 2.66 cm (untreated) to 1.4 cm (treated with 60% conc.) and from 5.375 cm (untreated) to 3.1 cm (treated at 60% conc.) in the warp way and weft way cut samples respectively. As a result, the fabric’s overall texture and drape are enhanced due to its increased flexibility and pliability.

Similarly, increased crease recovery angle from 143°(untreated) to 163° (treated with 60% conc.) indicates that the fabric is more supple and resistant to creasing when treated with softener. Therefore, the physical comfort and performance of the treated fabric are improved. Despite these advantages, higher concentrations of the treatment result in a significant decrease in tensile strength from 44 kgf (untreated sample) to 30 kgf (treated with 60% conc.) and from 22 kgf (untreated sample) to 13 kgf (treated at 60% conc.) in warp and weft directions respectively. As the seam strength is correlated to tensile strength, the findings show that the seam efficiency has dropped from 57.9% (untreated) to 30% (treated at 60% conc.) and from 15.9% (untreated) to 11.5% (treated at 60% conc.) in warp and weft directions respectively. Despite this limitation, the results show that T. chebula is a potential eco-friendly softening alternative in the textile finishing processes.

Considering the above constraints, future studies could focus on enhancing the softener-treated fabric’s tensile and seam strengths. Moreover, researchers can study the softener effect on additional properties including performance and tactile properties of textile fabrics. The effect of softener can also be studied for other plant-based fibers. Additionally, future research could focus on improving the extraction methodology of T. chebula and examining its wider range of potential uses. Moreover, researchers can expand the study of the effects of T. chebula softeners and discover novel techniques for improving fabric quality without compromising desired properties.

Highlights

• The United Nations Sustainable Development Goals include the promotion of ecologically friendly and sustainable methods, such as the use of plant-based fibers. The study focuses on a sustainable method of treating banana fabric with a softener which utilizes the natural material Terminalia chebula.

• Banana fiber is a “bast” fiber that closely resembles the appearance of natural bamboo and ramie. Although banana fabric serves as a great substitute for natural fabrics while retaining all their properties, its rigid texture limits its application versatility.

• The application of softening agents helps obtain a smooth texture; however, chemical treatment of a natural fabric compromises its sustainability.

• Given these, a highly medicated Terminalia chebula that exhibits good antibacterial and mordant properties is used. Examining the softening property of Terminalia chebula, which is abundant in saponins (also known as natural surfactants), is the novelty of this paper.

• A study was conducted to evaluate the impact of a natural softener Terminalia chebula finish, on the physical and mechanical properties of banana fabric.

Disclosure statement

No potential conflict of interest was reported by the author(s).