What is Lycra?
Synthetic or man-made fiber made of polyurethane is called spandex. When it was initially manufactured by DuPont in the US in 1959, it was sold under the brand name LYCRA.
Lycra Damage:
This is a defect where the Lycra yarn moves away from the edge of the cut fabric towards inside, thereby creating looseness in fabric where the Lycra is missing. Lycra damage is a defect which will appear as stamped wavy effect (bubble effect) on a flat surface.
Appearance of Lycra Damage on garments:
CASE STUDY:
We have chosen a sample with worst lycra damage in front rise area and side seam area.
We made few options to minimize the lycra damage and the following are the options.
Option 1:
• Fly Extension bottom staggered and finished with overlock. Fly & fly extension staggered keeping ¼” to 3/8” space.
• Poly paper is placed in between the fly facing and fly extension while sewing. This will avoid contact between fly extension bottom ends to body and minimize Lycra damage.
Outside view of the garment after washes for option 1. Dramatically improved lycra damage.
Option 2:
• Front rise construction changed to felled seam instead of overlock to arrest the elastic yarn slipping in from the seam edge.
Outside view of the garment after over dye for option 2. There is no lycra damage noticed.
Option 3:
• Added fusible tape at front rise seam.
• Added fusible tape at side seam.
Inside view of front rise and side seam area after wash.
No Lycra damage found after wash.
Option 4:
• Added voile/sheeting fabric across the fly & front rise on inside to restrict the front panel from stretching, especially at front rise.
Summary of case study:
• For the styles that has no top stitch or only edge stitch or only distance stitch like 1/8” SNTS or 1/4” SNTS (where we cannot do fell seam), OPTION 1 construction can be followed which serves better result.
• For the styles with DNTS at Front rise, we can follow OPTION 2 (Felled seam construction) and the results are good.
• If lycra damage occurring even after the above construction, we can go for OPTION 3 and OPTION 4 considering the SMV of the garment and Fusible tape costs.
• Need to do the above trials on construction in the initial stage and get confirmed with buyer on construction.
• Need to alert the Fabric team on the Lycra damage issue in the Fabric and escalate it to mill to get the fabric finished with special finishes that can minimize the Lycra damage.
• Need to work with washing team on adding special chemicals like “Cell soft 32 with Leaga finish” that are available to reduce the lycra damage as washing/overdyeing is one of the key process where lycra damage occurs due to Heat / wash cycles etc.
Do’s and Don’ts in Cutting & Sewing
• Cutting Knife should be sharp enough and frequent checking & replacement routine to be done in cutting section.
• No notching on panels, either in cutting or sewing. Marking instead of notching can be followed.
• No drilling or needle marking for pocket placements. Instead please provide a template to mark the pocket placements in-line.
• CF Keyhole & button attaching area –additional reinforcement could be given using Interlining patch (if a thinner interlining is being used for particular style, additional reinforcement layers could be added).
• Bartacks should be done only after wash if lycra damages noted at bottom of belt loop, Side cord stitch bottom and back pocket corners etc.
• SAN10 FFG point needles to be used to avoid damages to fabric yarn for all operations, especially chain stitch/FOA seams.
• Fly facing and fly extension should not end at same length, which makes the seam bulky. Hence the fly facing and extension should be staggered.
• If the style takes front rise with DNTS, a felled seam is preferable than o/l, as felled seam can minimize lycra damage.
PREVENTIVE ACTIONS TO BE DONE IN FABRIC / SEWING/WASHING:
Fabric:
Stretch and Recovery:
• All stretch fabrics should meet the stretch and recovery test parameters.
• 95% of the fabrics which fails in stretch and recovery test will have severe lycra damage issue.
• Lycra damage cannot be avoided completely in this fabric and hence need to rework on FABRIC to improve its properties.
Finish of the Fabric:
• If the fabric is prone to Lycra damage, we need to highlight the same to mill in the development stage itself and get the fabric finished with special softeners like anti-slipping agents which can minimize the Lycra damage.
• Get re-processed fabric and do trials with precautions in cutting and sewing to confirm before commencing for Bulk.
• Heat setting process is one of the keys which affect the elastic yarn in the fabric.
• If mill is doing Heat setting / compacting, we need to ensure the fabric test report should be done on the heat set / compacted fabric to get actual values on stretch & recovery and dimensional stability.
Sewing:
• Sewing SPI need to follow 10 - 12.
• Coarser thread must be avoided during sewing and thread tension need to manage accordingly.
• The sensitive arias like zipper fly up to front rise and side seam bar tack aria need to baby stitch to lock mouth of spandex. This case spandex cant coming out by pulling.
• Use SES (Gold plated Micro Ball Point) needle only.
• Machine RPM must be controlled by maintenance team according to fabric.
• Over stitch or back tacking is one of the most important issues for lycra damage. It should be avoided as much as possible.
• Appropriate position of presser on presser foot .Check the plate & teeth.
Washing:
Ratio of chemical:
• Proper ratio of the chemical is one of the most important elements for wash.
• Excessive amount of enzymes and bleaching agents will harm the elastic yarn.
• Repeated wash with the enzymes and bleaching agents will increase the chances of lycra breakage occurring.
Temperature and wash time:
• When the elastic yarn gets contact with high temperature, it becomes more of a plastic and easy to break.
• High temperature and high wash time will always harm elastic yarn.
• Some special chemical like “Cellsoft 32 with Leaga Finish” has been developed to avoid Lycra / spandex
deformation. Use of such chemical in the dyeing and washing will reduce lycra deformation or spandex
deformation.
• Hydro-extractor pressure should be lower than the regular setting.
• Using silicon softener at the stage of de-sizing, the surface of the fabric becomes slippery thus it avoids the abrasion and reduce Lycra or spandex deformation.
Washing Team to Ensure:
• Garment received with proper precautions taken like adding poly cover at Fly bottom as explained.
• Zippers should be covered with cotton sheeting or any lining fabric to avoid metal contact on the fabric surface.
• Pockets should be basted close.
• Pocket flaps should be gun tacked with Small plastic bullet to make sure it will not free to open to avoid stress at
flap corners.
• Garments should not be tied hard during receive and delivery time. It will destroy the elasticity of the fabric.