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Monofee's RT two-component foldable monofilament has become the preferred material for many fabric manufacturers due to its excellent technical performance and wide range of application scenarios. This monofilament is not only fold-resistant, wear-resistant, low shrinkage and good feel, but also provides reliable guarantee for the production of various high-end upper materials.

Definition and structural analysis

RT bicomponent fold-resistant monofilament yarn is a high-performance monofilament yarn with a "core-sheath" bicomponent design. It forms a composite structure consisting of a high-melting-point core and a low-melting-point outer layer by coaxially compounding two different polymers in a certain proportion during the same spinning process.

Core material: High-strength and high-elastic polymers such as thermoplastic polyether ester (TPEE) are usually selected to provide the load-bearing and resilience performance of the yarn.
Sheath material: Low-melting-point polyester or special copolymer can be selected to achieve the functions of yarn tieability, water resistance, and UV resistance.
The "secret" of fold resistance: By precisely controlling the molecular chain orientation and interface bonding of the two materials, the yarn can still maintain structural integrity and stable mechanical properties after thousands to tens of thousands of folds, avoiding microcracks or breaks in traditional monofilaments after bending.

The above-mentioned two-component structure not only improves the folding resistance of the monofilament, but also can customize the sheath function (such as waterproof, UV resistance, conductivity, etc.) according to application requirements, achieving high added value in multiple scenarios.

Production process and technical advantages

Raw material pretreatment and ratio

Select raw materials such as TPEE, polyester or TPU, and use a drying oven to dehumidify to a moisture content of <0.02%.

Optimize the core/sheath mass ratio (commonly 70:30 to 50:50) based on the target performance (such as tensile strength, rebound rate, sheath melting temperature).

Two-component melt spinning

Melt extrusion: Use a twin-screw extruder, heat the core material to 230-250 ℃ and the sheath material to 200-220 ℃, respectively, and feed it into the two-component spinning die under the control of a high-precision proportional pump.

Composite spinning head: The core and sheath materials pass through a coaxial channel to complete the "core-sheath" co-extrusion in the spinning head to ensure that there is no stratification and no bubbles at the interface.

Cooling and stretching

Water tank cooling: The yarn enters a constant temperature water tank (temperature 22±2 ℃) immediately after coming out of the spinning head to quickly solidify the outer layer.
Stretching and shaping: Through the two-stage stretching machine, the total stretching ratio is 3.5-5.0×, and the stretching temperature (80-120 ℃) is controlled to adjust the molecular chain orientation, so as to obtain the best tensile strength and resilience.

Post-processing and quality inspection

Heat setting: In the 110-130 ℃ hot air setting tunnel, the yarn structure is locked to improve dimensional stability.
Dyeing/functional finishing: Disperse dyeing, waterproof coating or antibacterial finishing are carried out according to needs.
Quality inspection: Including indicators such as diameter deviation (±0.01 mm), tensile strength, elongation at break, Gelbo folding test, etc., to ensure that each batch of products meets the standards.

Technical advantages

Precise two-component ratio and stretching process to achieve excellent folding and fatigue resistance.
The core/sheath materials can be flexibly replaced to quickly respond to customized functional requirements.
Compared with single-component yarns, the material utilization rate is higher and the production efficiency is better.

Product Specifications

Product Specifications: The specification range of RT monofilament is 0.1~0.22mm, which meets the needs of different upper materials.

Common specifications: Among them, 0.1mm and 0.12mm are the most commonly used specifications, suitable for most woven, warp knitted and flying woven uppers.

Melting point: The melting point of this monofilament is 220℃, and it can still maintain its physical properties in a high temperature environment to ensure high-quality molding of the upper.

Color and customization: RT bicomponent foldable monofilament provides a variety of options including transparent, black and colorful, and supports customer customization needs, which can fully match the designer's creativity and product positioning.

Product Features

Folding resistance: RT bicomponent monofilament has been specially processed and has excellent folding resistance. Even under high-intensity use, it can still maintain its structural integrity and ensure the long-term durability of the fabric.

Wear resistance: The wear resistance of this monofilament is extremely excellent, which is suitable for frequently used upper materials. It can effectively extend the service life of the upper and reduce wear caused by friction.

Low shrinkage: Monofee's RT monofilament undergoes strict process control to ensure its dimensional stability under high temperature and high pressure conditions. Its low shrinkage characteristics greatly reduce the risk of dimensional changes in the fabric during processing and use.

Comfortable feel: RT monofilament has a soft and smooth feel, which makes it particularly good in the manufacture of high-end uppers, ensuring the comfort of the product and improving the overall texture.

Application scenarios

RT two-component foldable monofilament is widely used in the production of various high-performance upper materials, including but not limited to:

Woven uppers: As a high-strength, wear-resistant upper material, RT monofilament can ensure the stability and durability of the upper, and is suitable for various sports shoes and casual shoes.

Warp knitted upper: In the warp knitting process, the low shrinkage and excellent feel of RT monofilament make it an ideal choice for upper materials, helping to produce highly elastic and structurally stable uppers.

Flying woven upper: For the flying woven process, the folding and abrasion resistance of RT monofilament provides better support for the upper, meeting the requirements of lightness, durability and elegant appearance.

Practical Guide: How to Select and Apply

Clear Performance Requirements

Tensile Strength vs. Elongation: If you emphasize support, you can choose a high core content (70–80%); if you emphasize soft fit, then the core is 60%↓.
Anti-fatigue vs. wear resistance: Increasing the thickness of the sheath or using a highly wear-resistant polymer (such as TPU) can improve the wear resistance of the outer layer.

Process Parameter Optimization

Melt temperature: core TPEE 230–250 ℃, sheath polyester 200–220 ℃ (±5 ℃); too high temperature is prone to degradation, too low temperature is prone to interface non-bonding.
Stretch ratio: The total stretch ratio is recommended to be controlled at 3.5–5.0×, the stretching temperature is 80–120 ℃, and the stretching rate is 0.5–1.2 m/min.
Cooling method: constant temperature water tank (22 ℃), cooling section length 2–3 m, to ensure that the outer layer solidifies quickly and the core material has enough time to set.

Essential for quality inspection

Diameter inspection: Use a laser diameter gauge to ensure ±0.01 mm.
Mechanical properties: Use an electronic tensile machine to test tensile strength and elongation at break.
Folding test: Gelbo folding (ASTM F392) Condition A (2700 times) and Condition B (900 times) double testing are recommended.

Application skills

Color matching and dyeing and finishing: Try to use disperse dyes or molecular mixed dyeing to avoid macromolecular pigment deposition affecting interface bonding.
Functional finishing: If waterproofing is required, nano-fluorination or silane coating can be performed in the post-processing stage; for antibacterial, nano-silver or quaternary ammonium antibacterial agent finishing can be selected.

Supply chain and cost control

Cooperate with reliable suppliers (such as Monofee) to ensure stable raw material quality and controllable delivery time.
In mass production, the cost can be reduced by 5–10% through ratio optimization and process improvement while ensuring quality.

Monofee Factory Advantages

As a leader in the field of monofilament yarn manufacturing, Monofee Monofilament Yarn Factory has world-class production equipment and advanced technical processes. Our factory is not only equipped with a fully automated production line, but also introduced internationally advanced quality testing equipment to ensure that the quality of each monofilament meets or even exceeds industry standards.

Technological innovation: Monofee has always been committed to technological innovation and has an experienced R&D team to continuously optimize product performance to meet the latest market needs.

Large-scale production: Our factory has a strong production capacity and can respond quickly to large-scale orders to ensure a stable and worry-free supply chain for customers.

Quality Assurance: From the purchase of raw materials to the delivery of finished products, Monofee implements a strict quality control process to ensure that each batch of products can pass the most stringent testing and meet the high standards of customers.

Customization Service: We provide flexible customization services, which can adjust product specifications, colors and other characteristics according to the specific needs of customers, truly realizing the personalized production of products.

Conclusion

Monofee's RT two-component foldable monofilament provides a solid guarantee for the manufacture of high-end upper materials with its excellent folding resistance, wear resistance and low shrinkage performance. Whether it is woven, warp knitted or flywoven uppers, RT monofilament can perform the task excellently and improve the overall quality of the product. Choosing Monofee is to choose the guarantee of excellent quality and reliable performance.