Differences in Core Principles of Processes (Molecular Perspective)
1. Addition of masterbatch (pre spinning process)
Definition: functional components such as antioxidant, light stabilizer, UV absorber, etc. are fused with carrier resins (such as PP, PE) through twin-screw extruder to produce high concentration functional master batch, and then mixed with base material chips in a certain proportion (usually 5% -20%). After spinning, drafting, netting, and hot rolling, the “molecular fusion” of anti-aging components and fibers is achieved.
Molecular action logic: anti-aging ingredients are evenly distributed inside the fiber, forming physical entanglement or weak chemical bond combination with the molecular chain of the substrate, building a “global protection network” from the core to the surface of the fiber, and free radical capture, UV shielding and other effects penetrate the fiber as a whole.
2. Post finishing (post spinning process)
Definition: After the non-woven fabric is formed, the anti-aging functional fluid (including antioxidant, light stabilizer, UV absorber, adhesive, penetrant, etc.) is attached to the fiber surface by means of dip rolling, spraying, coating, vacuum adsorption, etc., and is dried and solidified to form a protective layer.
Molecular action logic: anti-aging ingredients only stay on the fiber surface or shallow layer (penetration depth is usually ≤ 1 μ m), and form adhesion with the hydroxyl and carboxyl groups on the fiber surface through adhesives. It mainly relies on the surface protective layer to block UV and free radicals, which belongs to “surface protection”.
Comparison of Core Advantages and Disadvantages (Multidimensional Quantitative Analysis)
Aging resistance uniformity
Mother particle addition (pre spinning process)
✅ Advantages: the components are evenly dispersed inside the fiber (dispersed particle size ≤ 5 μ m), there is no local protection blind area, and the overall anti-aging performance of the fabric is consistent. Data: In QUV aging testing, the difference in retention rate of fracture strength in different areas of the fabric is ≤ 3%.
Post finishing (post spinning process)
❌ Disadvantages: prone to “surface unevenness” (local concentration differences caused by liquid flow during spraying/rolling), weak protective layer at edges and folds. ・ Data: The concentration deviation of anti-aging components in local areas can reach 30% -50%, which is prone to “local embrittlement” after aging.
Long term stability
Mother particle addition (pre spinning process)
✅ Advantages: anti-aging components are wrapped by fiber molecular chains, which are not easy to migrate, precipitate and lose, and the protective effect is lasting. ・ Data: After 3 years of outdoor use, the retention rate of anti-aging ingredients is ≥ 80%; QUV aging for 2000 hours, with a fracture strength retention rate of ≥ 70% (suitable for long-term outdoor scenarios).
Post finishing (post spinning process)
❌ Disadvantage: The ingredients only adhere to the surface, making them susceptible to friction, washing, and rainwater erosion, resulting in a short protection period. >Data: After 6-12 months of outdoor use, the ingredient loss rate is ≥ 50%; After 3 washes, the UV shielding rate decreased from 95% to below 40% (only suitable for short-term use).
Molecular level protective capability
Mother particle addition (pre spinning process)
✅ Advantages: It can resist both photo oxidative and thermal oxidative aging, and its components penetrate deep into the fiber, capturing free radicals in the fiber core and blocking the “root cause” of molecular chain breakage. Adaptation: It can be combined with copolymerization, cross-linking and other substrate modifications to form a synergistic effect of “internal strengthening+comprehensive protection”.
Post finishing (post spinning process)
❌ Disadvantage: It can only block surface UV and external free radicals, and cannot cope with thermal oxidative aging inside the fiber (such as chain reactions caused by residual free radicals during processing), and internal damage to molecular chains may still occur. Limitations: Unable to cooperate with substrate modification, protection only stays at “surface interception”.
Process complexity and cost
Mother particle addition (pre spinning process)
❌ Disadvantages: Additional investment in masterbatch preparation equipment (twin-screw extruder, about 500000 to 1 million yuan) is required, with a high proportion of masterbatch addition (5% -20%) and high raw material costs; The spinning process requires temperature and speed control to avoid uneven dispersion of masterbatch, and strict process parameter requirements. Unit cost: 0.8-1.5 yuan/square meter higher than pure non-woven fabric.
Post finishing (post spinning process)
✅ Advantages: No need to modify spinning equipment, only need to add a post-processing production line (immersion mill/spraying machine, about 100000-30000 yuan), low concentration of functional solution (effective ingredient 1% -5%), and low raw material cost; The process operation is simple, and different anti-aging formulas can be quickly switched. >Unit cost: 0.2-0.6 yuan/square meter higher than pure non-woven fabric.
Impact on fabric performance
Mother particle addition (pre spinning process)
✅ Advantages: The components have good compatibility with the substrate, which does not affect the mechanical properties of the fibers (fracture strength, elongation), and can even improve the stiffness of the fabric through filling modification. ・ Data: The breaking strength of PP non-woven fabric added with 10% anti-aging masterbatch is only 2% -3% lower than that of pure PP.
Post finishing (post spinning process)
❌ Disadvantage: Adhesives can easily cause fiber adhesion, reducing fabric breathability by 15% -30%; Surface coating may increase fabric brittleness and reduce fracture elongation by 10% -20%; Some adhesives have poor weather resistance and are prone to yellowing and powdering after aging.
Environmental friendliness and safety
Mother particle addition (pre spinning process)
✅ Advantages: no volatile organic compounds (VOC) release, stable combination of anti-aging ingredients and base materials, no migration risk, in line with food contact, medical and other safety standards (such as FDA, GB 15979).
Post finishing (post spinning process)
❌ Disadvantage: Functional fluids may contain solvents and adhesive residues (such as formaldehyde and VOCs), posing environmental risks; The ingredients are prone to migrate to the surface of the contact material and are not suitable for scenarios such as food packaging and medical protection.
Applicable scenario adaptability
Mother particle addition (pre spinning process)
✅ Adaptation: Long term outdoor use (geotextile, bird proof net, sunshade net), high requirement protection (car interior, outdoor tent), safety sensitive scenes (food packaging, medical non-woven fabric).
Post finishing (post spinning process)
✅ Adaptation: short-term outdoor use (temporary sunshade cloth, disposable outdoor products), indoor scenes (curtains, decorative cloth), low-cost mass production (ordinary agricultural covering cloth).
Key supplement: Process selection logic for special scenarios
1. Priority should be given to selecting the scene where the masterbatch is added
The outdoor service life requirement is ≥ 3 years: for example, geotextile (requiring 5-8 years of weather resistance), agricultural bird proof net (requiring 3-5 years of UV resistance), and the “comprehensive protection” added by masterbatch can avoid later aging and failure;
High safety and compliance requirements: For example, non-woven fabrics used in contact with food (must comply with GB 4806), medical protective non-woven fabrics, and masterbatch additives have no risk of component migration, resulting in better safety;
The mechanical properties are required to be stable: for example, outdoor tent and automobile interior non-woven fabrics, both anti-aging and tensile toughness should be taken into account, and the addition of masterbatch has little impact on the fabric performance.
2. Optional post-processing scenes
Short term use (≤ 1 year): such as temporary construction enclosures, disposable outdoor advertising fabrics, with significant cost advantages in post finishing, and no need for long-term protection;
Small batch and multi batch production: such as customized sunshade cloth (with different UV protection levels), which can quickly switch formulas after finishing, with higher flexibility;
Low budget scenario: such as ordinary agricultural covering cloth (1-2 season service cycle), post finishing can reduce production costs and meet basic anti-aging needs.
Process optimization direction (highlighting strengths and avoiding weaknesses)
1. Optimization of masterbatch addition
Adopt “nano dispersion technology”: activate anti-aging ingredients (such as nano TiO2, HALS) by coupling agent, reduce the dispersed particle size to 1-2 μ m, improve the protection efficiency, reduce the addition amount of master batch (from 10% to 5% -8%), and reduce costs;
Develop “multi-functional composite master batch”: integrate the functions of anti-oxidation, light stability, anti-bacterial, etc., reduce the types of master batch, and simplify the spinning process. For example, PP anti-aging anti-bacterial composite master batch can meet outdoor weather resistance and health requirements at the same time.
2. Post organized optimization
Choose “reactive adhesives”: such as polyurethane adhesives, which can form chemical bonds with the surface of fibers, improve component adhesion, and reduce loss (outdoor use cycle extended from 6 months to 1-2 years);
Adopting a “multi-layer coating process”: first apply a penetration layer (to increase the penetration depth of the components), then apply a protective layer (to strengthen surface shielding), to improve the limitations of “surface protection”. For example, using a composite process of immersion rolling and spray coating, the UV shielding retention rate is increased by 40%.
Dongguan Liansheng Non woven Technology Co., Ltd. was established in May 2020. It is a large-scale non-woven fabric production enterprise integrating research and development, production, and sales. It can produce various colors of PP spunbond non-woven fabrics with a width of less than 3.2 meters from 9 grams to 300 grams.
Post time: Mar-01-2026