Colorfastness Retention of Non-Infill Grass Fibers: Full-Chain Technical Solutions from Materials to Application Scenarios

In non-infill grass, fibers are fully exposed to sunlight, rain, chemicals, and mechanical abrasion due to the absence of infill particles, making colorfastness a critical factor for longevity and visual quality. According to GB/T 20394-2019 “Artificial Turf for Sports” standards, sports-oriented non-infill grass must achieve weathering colorfastness ≥5, green grass gray scale ≥4, and functional white lines gray scale 4–5. Effective color retention relies on a comprehensive design strategy encompassing source-level stabilization, process-level pigment locking, and scenario-specific adaptation. Drawing from vivaturf’s practice, this article analyzes colorfastness retention through four key stages: raw material modification, additive systems, production processes, and scenario-based protection.
1. Raw Material Modification: Embedding “Anti-Aging Genes” in Base Resin and Masterbatch
Fiber matrix stability and pigment dispersion determine fundamental colorfastness. Material modification and masterbatch optimization reduce fading risk at the source. High-crystallinity PE/PP composites are widely adopted in non-infill grass. Linear low-density polyethylene (LLDPE) with ≥65% crystallinity provides a dense molecular network that minimizes UV penetration and inhibits water and chemical ingress. Polypropylene (PP) blended at 30% imparts rigidity (Shore D60) to reduce pigment removal caused by abrasion. vivaturf football fibers using this matrix retained gray scale ≥4 after 10,000 abrasion cycles, outperforming the industry average of 3. Pigment masterbatches are optimized via high-concentration, nano-dispersed inorganic pigments (≥35% concentration, e.g., phthalocyanine green, titanium dioxide). Nano-dispersion (50–100 nm) ensures uniform embedding between polymer chains, preventing localized fading. Pigment carriers are matched to the fiber resin to form molecular-level integration, avoiding pigment migration during processing or use. Crosslinking techniques enhance structural stability in extreme climates. Silane crosslinking (1–2%) during extrusion forms a 3D network locking pigments, preserving colorfastness at −30°C. Electron-beam irradiation further densifies polymer chains, improving pigment adherence by 30%, as evidenced in vivaturf FIFA two-star certified fields, showing only 0.5 gray scale loss after five years of outdoor exposure.
2. Additive Systems: Triple Protection Against UV, Chemicals, and Abrasion
Additives serve as the frontline defense against external degradation. UV shielding employs both inorganic and organic absorbers. Nano-sized ZnO and TiO₂ (3–5%) block UVA/UVB and shortwave UV (<410 nm), reducing fiber UV transmittance below 20%. Additional SiO₂ enhances UV reflectivity to 85%. Benzotriazole UV absorbers (0.5–1%) convert absorbed UV energy into heat, preventing pigment degradation. Anti-oxidants (0.3–0.5% hindered phenols) mitigate oxidative yellowing. Solvent-resistant agents (e.g., 1% silicone masterbatch) create a hydrophobic barrier against oils and organic compounds, maintaining color integrity after immersion tests. Abrasion-resistant agents such as 0.5% PTFE micro-powder form a lubricating layer, reducing friction coefficients below 0.15, preserving pigment layers even under heavy sports usage. Carbon black (2–3%) enhances both color density and UV resistance for dark fibers.
3. Production Processes: Locking Color from Extrusion to Fiber Formation
Processing parameters critically affect pigment dispersion and adhesion. Gradient temperature extrusion (160°C pre-melt → 180°C melt → 170°C homogenization) prevents localized pigment decomposition. Twin-screw extruders at 300 rpm ensure 98% mixing uniformity. Fiber drawing uses slow stretch rates (<20 m/min, 3:1 draw ratio) with water-bath annealing at 40°C to maintain molecular chain stability and uniform color distribution. Post-treatment includes 0.1 mm silane coatings forming transparent protective films and low-temperature thermal curing at 80°C for 2 hours, reinforcing pigment-polymer bonding.
4. Scenario Adaptation: Tailored Protection for Environmental Variability
Environmental factors differ across regions, requiring customized solutions. High UV exposure (plateaus, southern regions) employs increased UV shielding (up to 5% additives), achieving colorfastness up to 6. High-temperature LLDPE and benzotriazole absorbers maintain ≥5 in southern climates. High humidity and chemical exposure (coastal, poolside) use salt-resistant additives (1.5%) and chlorine-resistant masterbatches (0.8%) to maintain gray scale 4–5. High-abrasion environments (sports fields) leverage PP-reinforced fibers and PTFE, with tuft density of 15,000/㎡, retaining ≥97% abrasion and gray scale 4. Recreational areas use silane coatings and high-concentration inorganic pigments, ensuring negligible color loss over 2 years.
5. vivaturf Full-Chain Implementation: Case Examples
vivaturf applies an integrated “materials-additives-process-scenario” strategy ensuring compliance with GB/T 20394-2019. Professional sports series: high-crystallinity LLDPE/PP + 35% inorganic pigments + 5% UV shielding, FIFA two-star certified, weathering colorfastness 5, abrasion 4. Children’s series: silane-crosslinked base + silane coating + ternary UV system, weathering colorfastness 5.5, 48h acid-base stability, suitable for kindergartens. Extreme environment series: cold-resistant northern variants, water-resistant southern variants, salt-resistant coastal variants, achieving 8–10 years effective lifespan.
Colorfastness Requires Full-Chain Coordination and Targeted Protection
Maintaining non-infill grass colorfastness depends on synergistic measures across materials, additives, processing, and environmental adaptation. Key considerations for selection include weathering colorfastness ≥5, abrasion colorfastness ≥4, and 48-hour acid/base resistance. Matching solutions to use scenarios—high UV for plateaus, salt-resistant for coastal regions, abrasion-resistant for sports fields—ensures long-term visual and functional performance.

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