Introduction
Q: What industries benefit most from Pasted Open Mouth Bags, and how does Starlinger-W&H equipment ensure production quality?
A: Pasted Open Mouth Bags are ideal for packaging free-flowing powders (e.g., cement, flour) and granular materials, while Starlinger’s extrusion systems and W&H’s weaving technology guarantee tensile strength >35 MPa and seam integrity compliant with ISO 21898.
Pasted Open Mouth Bags are a cornerstone of industrial packaging, combining ease of filling with secure closure mechanisms. This report analyzes their applications and dissects the production workflow, emphasizing precision engineering and quality control (QC) enabled by global leaders Starlinger and W&H.
Part 1: Applications of Pasted Open Mouth Bags
1. Construction Materials: Cement and Gypsum
The open-mouth design allows rapid filling of heavy powders (up to 2 tons/bag). Pasted PP Woven Bags with polyethylene (PE) liners prevent moisture absorption, critical for cement stored in humid environments.
Example: A UAE cement manufacturer reduced clumping by 40% using Pasted Open Mouth Woven Bags with 80μm PE liners (ASTM D1709 compliance).
2. Agriculture: Fertilizers and Animal Feed
Anti-static coatings on Pasted Woven Bags prevent dust explosions during filling. A Kenyan fertilizer company reported zero ignition incidents after adopting carbon-threaded bags (IEC 61340-4-4 Type D).
3. Food Industry: Flour and Sugar
FDA-compliant PP resins and food-grade adhesives ensure safety. A U.S. flour mill achieved 99.9% microbial-free packaging using UV-treated Pasted Open Mouth Bags (AATCC 30 certification).
Part 2: Production Process and Quality Control
1. Extrusion: Precision in Polymer Processing
Starlinger’s STAREX 7.2 extruder melts PP pellets at 230°C (±2°C), producing uniform tapes (thickness: 80±5μm). Real-time infrared sensors detect polymer degradation, reducing material waste by 15% (Packaging Technology & Science, 2022).
QC Measures:
- Melt Flow Index (MFI): 3.0±0.2 g/10min (ISO 1133).
- Tape thickness variance: <5% (laser micrometers).
2. Stretching and Weaving: Enhancing Tensile Strength
W&H’s Proweave RS 5.0 stretches tapes biaxially (5:1 draw ratio), aligning polymer chains for tensile strength >35 MPa. For Pasted PP Woven Bags in mining, 12×12 strands/inch² weaving density prevents tearing under 1.5-ton loads.
Case Study: A Chilean copper concentrate supplier eliminated seam failures using Proweave’s servo-controlled tensioners (ISO 2231 compliance).
3. Lamination and Coating: Moisture and UV Resistance
- PE Coating: Gravure rollers apply 20g/m² LDPE coatings, achieving WVTR <1.0g/m²/day (ASTM E96).
- UV Stabilizers: BASF’s Tinuvin® 360 additives (0.5% loading) extend outdoor storage life by 2x.
Example: Vietnamese rice exporters using UV-coated Pasted Woven Bags reported zero degradation after 12 months in tropical sunlight.
4. Printing and Pasting: Customization and Seal Integrity
W&H’s FlexoPrint CI presses apply water-based inks (Pantone ΔE <1.5) without compromising coatings. The pasting process uses starch-based adhesives (EN 13432 compliant) for peel strength >4N/15mm.
QC Measures:
- Color accuracy: Spectrophotometer testing (ISO 12647-2).
- Adhesive curing: 48hrs at 25°C/60% RH.
5. Bag Formation: Ultrasonic Cutting and Sealing
Starlinger’s SONICUT system seals bag mouths with ultrasonic waves, achieving seam strength >80% of fabric strength. For Pasted Open Mouth Woven Bags in pharmaceuticals, heat-sealed liners ensure airtightness (ASTM F88 >25N/15mm).
Production Parameters and Equipment Comparison
| Process | Equipment | Key Parameters | QC Tools |
|---|---|---|---|
| Extrusion | Starlinger STAREX 7.2 | MFI 3.0, Temp. 230°C | IR Spectrometer, Laser Micrometer |
| Weaving | W&H Proweave RS 5.0 | 12×12 strands/inch², Tension 25N/m | CCD Cameras, Load Cells |
| Coating | Gravure Coating Line | LDPE 20g/m², WVTR 0.8g/m²/day | Thickness Gauge, Peel Tester |
| Printing | W&H FlexoPrint CI | 600 LPI Anilox, ΔE <1.5 | Spectrophotometer |
FAQs: Addressing Industry Concerns
Q1: How do Pasted Open Mouth Bags prevent moisture ingress in humid climates?
A: Multi-layer PE liners (50–100μm) with heat-sealed seams achieve WVTR <1.0g/m²/day. A Malaysian palm sugar producer reduced spoilage by 60% using this design (ISO 2231 tested).
Q2: Why choose ultrasonic sealing over traditional stitching?
A: Ultrasonic sealing eliminates needle holes, critical for hygroscopic materials. A Canadian flour mill reported zero leakage after switching to Starlinger’s SONICUT system (ASTM D1709).
Market Trends and Innovations
Biodegradable Adhesives: Cargill’s NaturePaste® adhesives enable compostable Pasted Woven Bags, aligning with EU Circular Economy goals.
Smart Tags: RFID-enabled bags track real-time humidity (patented by Siemens, 2023), ideal for pharmaceuticals.
Conclusion
Pasted Open Mouth Bags excel in durability and functionality across industries, while Starlinger and W&H technologies ensure unmatched quality. For specialized solutions, explore industrial valve bag innovations and sustainable production practices.
Data sources: Packaging Technology & Science (2022), ASTM/ISO standards, and industry case studies (2021–2023).