Red low melting point fiber with its own red dyeing process, suitable for glue-free bonding and industrial filter felt

Red low melting point fiber with its own red dyeing process, suitable for glue-free bonding and industrial filter felt applications.

Specifications: 4D*51MM

Our 4D*51MM red low melting polyester staple fiber is a high-performance colored thermal bonding fiber developed for nonwoven products that require both reliable bonding function and decorative color effect. Combining advanced spun-dyed mass pigmentation technology with precision sheath-core composite spinning, it integrates permanent color retention, low-temperature bonding and excellent structural support.

Unlike ordinary surface-dyed low melt fibers that suffer from fading and color bleeding, this product incorporates red masterbatch into the fiber interior synchronously during the melt spinning stage. Pigment molecules are firmly encapsulated within the polymer matrix and will not migrate or rub off due to heating, friction or washing.

In terms of bonding performance, the fiber features a classic concentric sheath-core structure. The low-melting sheath melts uniformly at 110-130°C to create strong physical fiber-to-fiber bonds without any chemical adhesive. The 4D coarse denier design imparts outstanding rigidity and supporting force, making it highly suitable for thick nonwoven products, hard cotton and filter media.

The 51mm standard cut length delivers excellent carding performance and web formation, runs smoothly on all types of high-speed production lines, and generates low fly waste for high production efficiency.

• Footwear & Shoe Materials: Shoe lining decorative layers, insole bonding layers, toe puff colored reinforcement, sports shoe functional nonwovens
• Industrial Filtration: Filter layer color coding, dust removal filter felt, liquid filter media, air filter cotton colored separation layers
• Decorative Nonwoven: Festive decorative fabrics, holiday event nonwovens, gift packaging nonwovens, wall decoration cloth
• Automotive Interior: Car interior decorative trim, trunk lining colored layers, door panel sound insulation cotton decorative layers
• Packaging & Crafts: Gift box buffer filling, premium packaging decorative linings, festive craft supplies, handbag interlayer shaping layers
• Home Textile: Mattress colored border layers, sofa decorative linings, home textile functional decorative nonwovens

• Spun-Dyed Mass Pigmentation, Permanent Colorfast & Zero Dyeing Pollution: Vivid red color achieved by precision-dosing high-quality red masterbatch during spinning stage. Pigments permanently locked inside fiber body with washing and rubbing fastness above Grade 4.
• Precision Sheath-Core Structure, Adhesive-Free Low-Temperature Thermal Bonding: Advanced concentric sheath-core bicomponent spinning technology. Outer sheath melts at 110-130°C to form strong physical fiber-to-fiber bonds without chemical adhesives.
• 4D Coarse Denier + 51mm Universal Length, Strong Support & Wide Process Compatibility: Excellent fiber rigidity and structural supporting force. Universal length compatible with all mainstream carding machines, needle punching lines, and thermal calenders.
• Uniform Color & Tight Batch Control, Stable Mass Production Quality: Standardized closed-loop production ensures consistent color shade, fiber denier, length and melting point across every batch.
• Bright Standard Red Shade, Combined Functional & Decorative Value: Pure, bright and uniform standard red combining functional bonding performance with decorative appearance value.