Para aramid filament twisted sewing thread

Para-aramid fibers like Alkex® and Kevlar® present a host of qualities that render them superb for diverse applications. Their remarkable strength-to-weight ratio and superior break strength deliver outstanding tensile strength and modulus, rendering them perfect for applications demanding sturdy and enduring materials. These fibers prove ideal for situations where constant or repetitive loading is anticipated, thanks to their low elongation and resistance to creep.

Para-aramid fibers showcase outstanding resilience to elevated temperatures, retaining their mechanical integrity even under extreme heat. This characteristic renders them apt for use in thermal insulation and protective attire. Moreover, these fibers exhibit commendable resistance to various chemicals, enduring exposure to acids, alkalis, and numerous organic solvents without notable deterioration. Nonetheless, they are susceptible to UV radiation, which can lead to degradation and weakening over time. Consequently, safeguarding measures such as shielding from direct sunlight or prolonged UV exposure are necessary to uphold their efficacy and lifespan.

Para-aramid, surpassing the strength of steel, stands as a fiber of exceptional tenacity and modulus, retaining its robustness even under high-temperature heat aging. Tailored to fulfill stringent fire and heat safety criteria prevalent in aerospace, automotive, and insulation sectors, it emerges as a prime selection for safety gear and protective attire. Its applications extend to military usage and tape edging operations in mattress manufacturing.


 Composition: 100% para-aramid continuous twisted filament yarn

 Specification: 200D/2, 200D/3, 400D/2, 400D/3 1000D/2, 1000D/3, 1500D/2, 1500D/3, 3000D/2, 3000D/3


Color: yellow, black

Kevlar/Chinese brand para aramid

Features & Benefits

  • High Strength-Stronger than steel, para-aramid is a high tenacity, high modulus fibre and delivers high retained strength after heat ageing at elevated temperatures
  • Decomposition-Para-aramid starts to decompose (turn to ash) at approximately 800°F (426°C), withstanding much higher temperatures than nylon or polyester. PTFE-coated fiberglass offers even greater heat resistance, operating at temperatures up to 1022°F (550°C). For perspective, a disposable butane lighter burns at around 3578°F (1970°C). 
  • Melting – para aramid does not melt. This is essential in fire retardant gear.
  • Stretch – Kevlar thread stretches approximately 2% before breaking. For instance, a 100-foot piece of Kevlar would extend to 102 feet just before it breaks. When used to sew stretchy fabrics, Kevlar can cause the seams to pucker.
  • Acids and Alkalis – Kevlar thread has good resistance to dilute acids and bases. It is degraded by strong mineral acids and to lesser extent, by strong mineral bases. This is important when Kevlar thread is used in a laboratory setting.
  • Bleaching and Solvents – Kevlar thread should not be bleached. It has excellent solvent resistance. This matters when Kevlar gear is reused.
  • Mildew and Aging – Kevlar/Chinese brand para aramid thread has excellent resistance to mildew and aging.
  • UV Resistance – UV rays cause Kevlar to fade more quickly than many other thread types, and prolonged exposure to sunlight or even bright interior lighting can lead to deterioration. Therefore, it is recommended to store Kevlar thread in a dark place.
  • Abrasion – Kevlar thread has good abrasion resistance.


  • Bonded and Soft – “Bonded” refers to thread that has a coating, which reduces heat at the needle tip and prevents unraveling. “Soft” means the thread lacks this coating
  • Machine Sewing – Use bonded thread for sizes 69 and higher; for thinner threads, bonding typically isn’t necessary. Bonding can interfere with adhesives. It can be removed by soaking the thread in alcohol, but this may compromise its strength and heat resistance.
  • Hand Sewing and Hanging – Whether the thread is soft or bonded does not matter
  • Monocord – “Monocord” refers to thread made from a single ply with a bonded coating, giving it a flat, ribbon-like shape suitable for double-needle machines. Some of our lighter weight threads use this construction. When machine sewing with monocord, a tensioning adjustment is often necessary
  • S- Twist / Z- Twist Loose Twist / No Twist / and Yarn
  • Kevlar Thread Spool Sizes
    We sell most of our Kevlar/Chinese brand para aramid filament thread in small spool (100gram/200gram) as twisted filament are very smooth and in order to keep it stable we need it big bottom size. Any size can be tailor made per buyer requirement.


Para aramid  will degrade with prolonged UV light exposure. These fibers will brown and weaken over time.  Please keep this fiber stored away in a dark room and in the UV protective bag the fiber was shipped in.

Para aramid fiber will absorb atmospheric moisture up to 5-7% in weight. This fiber should be stored in a cool, dry room with low humidity. A desiccant bag was included with this fiber to prevent regain during transit and short-term storage at your facility.

Acid: Prolonged exposure to concentrated strong acids will cause degradation
Alkali: Degrades with prolonged exposure to Sodium Hypochlorite
Organic Solvent: Moderate degradation in Carbon Tetrachloride and Ethylene Glycol