Cailong

Introduction

In the evolving landscape of flexible packaging, the demand for high-barrier, transparent, and recyclable materials is stronger than ever. Silicon oxide (SiOx) coated films have emerged as a compelling alternative to traditional aluminum foil laminates, offering comparable barrier performance while maintaining transparency and enabling microwave compatibility. Guangdong Cailong New Material Co., Ltd. has introduced the BOPP-SiOx-TZ​ film, a 18-micron biaxially oriented polypropylene (BOPP) substrate with a vacuum-deposited SiOx coating. This article examines the product’s technical data sheet (TDS) in detail, covering dimensional accuracy, mechanical strength, surface properties, SiOx coating quality, barrier performance, and retort resistance.

Product Overview

BOPP-SiOx-TZ is designed primarily as a barrier layer in flexible packaging laminations. The recommended structure is:

BOPP // BOPP SiOx // RCPP

Key features include:

• Thickness: 18 μm (customizable width and length)
• Excellent oxygen and water vapor barrier
• Transparency and printability
• Retort capability at 121°C for 30 minutes
• Dual-side corona treatment (both SiOx side and BOPP side)

Dimensional Precision

The measured thickness of 18.1 μm is within tolerance, and the thickness deviation of only 5% indicates excellent extrusion and stretching control. Zero width deviation further ensures consistency in downstream converting processes.

Mechanical Properties

Notably, the transverse direction (TD) tensile strength reaches 238 MPa, far exceeding the 170 MPa minimum. This high TD strength benefits web handling during printing and lamination. The longitudinal elongation (186%) provides good flexibility, reducing the risk of cracking during bag forming and use.

Surface Wettability (Corona Treatment)

Both sides meet or exceed the 36 mN/m threshold, ensuring reliable adhesion for printing inks, adhesives, and coatings. The balanced treatment is critical for subsequent lamination processes.

SiOx Coating Quality

The 2% uniformity deviation​ is exceptionally low compared to the ±10% standard. This demonstrates outstanding control over the vacuum deposition process, which directly translates to consistent barrier performance across the entire roll – a vital factor for long-shelf-life packaging.

Barrier Performance

Test conditions: OTR per ASTM D-3985 at 23°C, 0% RH; WVTR per ASTM F-1249 at 38°C, 90% RH.

These results place BOPP-SiOx-TZ firmly in the high-barrier category. Compared to aluminum foil laminates, this film offers:

• Full transparency​ – consumers can see the product inside
• Microwave-safe​ – no metal layer to cause arcing
• Improved recyclability​ – an all-polypropylene structure (BOPP + RCPP) is more compatible with mono-material recycling streams

Retort Resistance

The TDS explicitly states “Retort condition at 121°C for 30 mins.” The film maintains its structural integrity and barrier properties after such severe thermal and pressure exposure. This makes it suitable for:

• Ready-to-eat meals (curries, soups, sauces)
• Pet wet food pouches
• Baby food packaging requiring sterilization

Ordinary BOPP films would shrink or melt under these conditions; the special base resin formulation combined with the SiOx coating enables this retort capability without sacrificing optical clarity.

Application Recommendations

The preferred laminate structure is:

复制Outer layer: BOPP (printable, glossy)
Barrier layer: BOPP-SiOx-TZ
Sealant layer: RCPP (retort-grade cast polypropylene)

This combination delivers:

• Outstanding visual appeal with high-gloss printing
• Reliable oxygen and moisture protection
• Strong heat seals that withstand retorting

Potential market segments include:

• Premium dry foods (nuts, coffee, milk powder)
• Retort pouch applications (growing ready-meal sector)
• Sustainable packaging transitions (replacing aluminum foil with transparent barrier films)

Conclusion

Cailong BOPP-SiOx-TZ demonstrates well-balanced and superior technical performance across all key parameters. The 2% SiOx uniformity​ and OTR of 0.35 cc/m²·day​ are particularly impressive, reflecting advanced manufacturing capability. While actual field performance depends on lamination processes, adhesive selection, and conversion conditions, this film represents a strong candidate for brand owners seeking transparent, high-barrier, retortable, and more recyclable packaging solutions.

For converters and packagers, it is advisable to conduct trial runs focusing on:

• Stress sensitivity of the SiOx layer during lamination (avoid excessive tension to prevent micro-cracks)
• Heat-seal compatibility with different RCPP grades
• Long-term barrier retention under real storage conditions

Overall, BOPP-SiOx-TZ strikes an excellent balance between high barrier, transparency, and retort endurance, positioning it as a future-ready material in the flexible packaging industry.