Hydrated Silica 165 — High-Abrasivity Whitening Toothpaste Grade
SEMITECH Hydrated Silica 165 is a precipitated silica engineered for whitening and stain-removal toothpaste formulations. Its ASTM RDA of 150–170 delivers the mechanical abrasion required to remove extrinsic stains from coffee, tea, red wine, and tobacco from the tooth surface, while remaining within the ISO 11609 accepted range for commercially available toothpastes. The product combines higher abrasivity with adequate surface area to support both cleaning and mild polishing action in premium whitening formulations.
Hydrated Silica 165 is fluoride-compatible and processes cleanly in planetary mixer and continuous toothpaste lines. The controlled d50 of 10–18 μm gives visible whitening efficacy while limiting aggressive particle-size outliers that could contribute to dentinal hypersensitivity.
Technical Specifications
| Properties and Test Methods | Unit | Typical Value | Standardization |
|---|---|---|---|
| BET specific surface area | m²/g | 100–140 | — |
| ASTM RDA | — | 150–170 | ISO 11609 |
| pH (10% slurry) | — | 6.5–9.0 | — |
| Loss on drying (105°C, 2h) | Wt% | ≤6.0 | — |
| SiO₂ content (dry basis) | Wt% | ≥94.0 | — |
| Oil absorption | mL/100g | 90–130 | GB/T 5211.15 |
| Heavy metals (as Pb) | ppm | ≤20 | — |
| Median particle size d50 | μm | 10–18 | — |
Application Suggestions
Whitening and Brightening Toothpaste
Hydrated Silica 165 is the primary active abrasive in adult whitening toothpaste formulations targeting extrinsic stain removal. The RDA 150–170 range provides the cleaning intensity that consumers associate with visible whitening results within 2–4 weeks of regular use, without requiring the addition of hydrogen peroxide or other bleaching chemistry. Typical loading is 15–25 Wt% in the finished paste.
Anti-Tobacco Stain Formulations
Tobacco stains are among the most tenacious extrinsic stains and require higher abrasivity than standard daily-care products. Hydrated Silica 165 is well-suited to anti-tobacco or smoker's toothpaste positioning where the formulator needs to justify a clinically meaningful stain-removal claim.
Professional-Grade Daily Whitening
For professional-channel products marketed through dental clinics or pharmacy premium shelves, Hydrated Silica 165 supports positioning around efficacy at moderate RDA — above mass-market daily-use grades but below the ceiling of specialist whitening pastes — making it appropriate for professional-strength daily whitening claims.
Premium Adult Toothpaste
In premium toothpaste SKUs competing on whitening and oral hygiene efficacy, Hydrated Silica 165 can be blended with lower-RDA grades (such as Hydrated Silica 113) to create a dual-function abrasive system that offers both daily cleaning and stain-removal in a single formula.
Technical Support & FAQ: Hydrated Silica 165
+Q1: What are the key performance characteristics?
The defining characteristic is the RDA 150–170 range, placing this grade in the moderate-high abrasivity category for whitening formulations. The higher BET (100–140 m²/g) compared to low-abrasivity silicas also contributes polishing action, and the d50 of 10–18 μm is carefully controlled to deliver visible whitening without creating aggressive particle-size outliers.
+Q2: How does it compare to the mild-abrasive Hydrated Silica 113?
Hydrated Silica 165 (RDA 150–170) targets whitening and stain-removal claims; Hydrated Silica 113 (RDA 100–120) targets daily-use and sensitive claims. Both are fluoride-compatible. The selection is driven by the consumer efficacy claim: a whitening toothpaste typically requires RDA above 130 to differentiate from daily-use grades.
+Q3: What factors affect pricing?
Oral care grade silica is produced under tighter purity and heavy-metals control than industrial grades, carrying a modest pricing premium. Key variables: volume (FCL pricing significantly below LCL), packaging (25 kg food-grade inner-PE-lined bags), and destination port. Contact info@semitechnm.com for a FOB Shanghai quotation.
+Q4: What are lead times and payment terms?
Standard lead time is 7–14 days from order confirmation for stocked grades. Payment terms: T/T, L/C, D/P. Free samples of 200g–1kg are available for formulation and RDA verification testing on request.
Packing & Storage Information
20′ FCL Container Approximately 18–20 MT in 25 kg multi-wall food-grade kraft bags, inner PE-lined. Palletized loading standard.
40′ HQ Container Approximately 20–22 MT in 25 kg bags or 500 kg jumbo bags. Jumbo bag format preferred by high-volume manufacturers with bulk silica handling infrastructure.
Storage Conditions Store in a cool, dry, well-ventilated warehouse away from moisture. Inner PE liner should be resealed after partial use. Shelf life is 24 months in original sealed packaging. Non-hazardous under normal storage and transport conditions.