Lycra Protector

People around the world becoming more conscious about their health and are getting engaged in various sorts of sports or fitness activities. This is creating huge demands in the sportswear market which is largely dependent on the availability of Lycra / Spandex.

Spandex fiber o ers excellent strength, weight and versatility which makes it very popular among textile manufacturers. It also finds wide usage in medical applications which is also contributing to the sales of the product.

Spandex is a synthetic polymer. Chemically, it's made from a long-chain polyglycol combined with a short diisocyanate, and contains a minimum of 85% polyurethane. This elastomer can be stretched to a certain degree and it recoils when released. These fibers are stronger, lighter, and more versatile. In fact, spandex fibers can be stretched to upto 500% of their length

The material is lightweight, elastic, stretchable and produces e ective resistance against perspiration, body oils, detergent and abrasions. It is used in the production of casual clothing, trekking pants, undergarments, home furnishing items among others

Physical Properties of Lycra:

Tenacity: 0.7 gm/den

Density: 1.21-1.35 gm/c.c

Elongation at break: 400-700%

Elasticity: Excellent

Moisture Regain (MR%): 0.6%

Resiliency: Very good

Ability to resist friction: Excellent

Color: White or near white

Ability to resist heat. Not good

Lusture: Less bright

Chemical Properties of Lycra:

1. Acids: Resistant to acids

2. Basic: Hot alkali damages the spandex

3. Effect of bleaching: Bleaching agent damages the fiber and it becomes weak.

4. Resistant to Organic solvent, light, mildews, insects

5. Dyes: Disperse dyes, Acid dye are suitable to dye spandex filament

Key benefits of Lycra:

• Exceptionally Elastic

• Stronger and more durable than conventional rubber

• Good tear resistance

• A third of the weight of natural rubber

• Clings to the body

• Comfortable

• Always reverts back to its original form after being stretched

• Crease Resistant

• Not sensitive to cosmetics, sun cream or seawater

• Easy Care

End uses of Lycra

Sport’s Wear Swimming suit, Aerobic suit, cycling jersey and shorts, netball body suits, rowing unisuits, etc.

Under Garments Bra cup, leggings, paity, under wear, socks, slacks, etc.

Women Wear Skinny jeans, mini skirt, tight fitted tops, jogging and exercising suits etc

Men’s Wear T-shirt, stretchable jeans, etc.

Medical Uses Surgical hose, orthopedic braces.

Home Furnishings Microbeaded pillows

Table 1 : End uses of Lycra

Lycra content in garments

Lycra Denim

Stretch jeans are likely the most popular type of jeans right now. Stretch jeans are a style of jeans made of stretch denim fabric. Stretch denim is a fairly new type of denim cotton (or cotton/ polyester blend) that incorporates a small quantity of Lycra, into the fabric. Jeans made of stretch denim material may look like regular jeans, but give further elasticity and “ give” with the wearer’s body movements. Stretch jeans are also generally more form- fitting than jeans made without any stretch in the fabric.

In the washing and dyeing process of denim products, once the spandex is degraded and the loss of elasticity occurs, it's principally impossible to repair, so it's necessary to preserve lycra to ensure that there will be no quality problems during washing. According to the physical and chemical properties of polyurethane filaments., Elastic denim products containing lycra cause loss of flexibility during the washing process, altogether due to the process, chemicals and mechanical action of the process itself which causes the lycra to break and dissolve, and eventually cause the loss of flexibility. During the rinsing process, because spandex isn't resistant to chlorine bleach, it'll form a nitrogen-chlorine bond in the hypochlorite solution to damage the fiber, and the damage of polyether spandex is more serious. When the water temperature in the tank is too high or the time is too long during rinsing, the spandex will degrade, causing the fabric to lose flexibility.

Lycra Damage

Lycra damage or breakage is a regular phenomenon in elastic or stretch garments manufacturing. Lycra breakage is also called Spandex missing or Lycra missing. This problem is not primarily detected while fabric manufacturing or processing but it is visible extensively just after garments washing. Spandex filament is damaged at an excessive temperature either in the heated chamber or in the steam compartment.

It is very sensitive to alkali, chlorine bleach and abrasion as well. Spandex filaments can be missed through the width of fabric. Spandex can be damaged in the garments stage during marking and just after cutting the cloths for sewing. Spandex filament comes out from fabric because of not having a tension after the selvage being cut. Tension variation in fabric also causes spandex breakage in the center position of the sheath. Generally, depending on the percentage composition of the Lycra/Spandex component and the overall fabric construction, the textile processor encounters problems like inadequate or excessive polymeric heat-setting resulting in fibre scorching, edge curling and loss in elasticity.

Remedial measures to avoid Spandex Breakage

• Minimise the SPI

• Use proper needles like ball point needle

• Dye the fabric at wet processing zone rather than dyeing at garments zone

• Do not use hot gun.

• Do not use alkali hypo bleach

• Do not stone wash

• Apply low temp.resin rather than high temp

• Use low temperature ironing

• Some special auxiliaries have been developed to avoid lycra / spandex deformation. (Lycra Protector)

Mechanism of Lycra Protector

Lycra protector is a polymeric compound that can penetrate inside the fibre, forms a thin protective/insulative layer and thus maintaining the elasticity of the fabric. In addition, it can act as anti-slipping agent to prevent the shrinkage or breakage of the stretch Lycra yarn in lycra and lycra blend fabrics. It can be used as Lycra protector in textile wet processes like desizing, oxidative bleaching, dyeing, heat setting etc

Features and Benefits

• Protects elasticity and strength of Lycra

• Applicable on natural, regenerated and synthetic fibers and their blends

• Retains inherent characteristic fiber properties

• Enhances surface softness and bounciness

• Imparts excellent non-slip effect

• Effective under varying acidic and alkaline pH conditions

• Stable to high electrolyte and water hardening agents

• Provides heat resistance and avoids thermal yellowing

• Forms a continuous, uniform, transparent film

• Confers desired dry hand feel

Fig 1: Possible mechanism of Lycra protector

FABPRO LP Liquid - is a unique protective chemical based on temperature regulating compound for controlling and minimizing the adverse impact of varying thermo-mechanical processing conditions commonly encountered in polyurethane based fabric. The undesired yellowing behavior and the grinning tendency of Lycra from the core of the fibre can be effectively overcome by the formation of a protective film. The ultimate effect is in terms of avoiding damage to Lycra and protecting the end use properties of textile material.

A special finishing agent can be applied to preserve lycra properties in garments. Rosil Stretch Liquid is a synergistic blend of reactive silicone and additives. It is a versatile finishing product that imparts permanent stretch property to knitted goods containing Lycra and a impart soft handle to woven goods as well. During processing due to the lubricating effect of yarns move more easily reducing the “pull” required to stretch fabric. Combo treatment with Fabpro LP Liquid can prove beneficial for lycra preservation.

Features and benefits

• Increasing the stretch and recovery characteristics.

• Luxurious soft handle

• Improved wearability after laundering

• Lightness

• Fits to the shape of your body => Well Crafted

• Impression that it is part of yourself

Conclusion

Traditionally, lycra fibers find application in products such as intimate wear and activewear, hygiene products such as diapers. However demand for daily wear and casual clothing with comfort, stretch, fit, and in daily wear, is influencing manufacturers to incorporate spandex fibers in the aforementioned clothing products.

Being petroleum-based, prices of these products are largely unpredictable. This negatively affects the profitability of spandex manufacturers and suppliers, and, in turn, inhibits request growth. Products such as Lycra protector will help to preserve lycra in a garment to improve the durability of same. Such products not only open new opportunities for textile makers but also help to meet the latest customer demands.