The 1mm rigid PP sheet featuring an EVOH high-barrier layer is a high-performance packaging material specifically designed for food-grade dairy thermoformed packaging (such as yogurt cups, pudding cups, fermented milk cups, etc.). By utilizing multi-layer co-extrusion technology, it combines the structural rigidity of rigid PP with the exceptional barrier properties of EVOH. This combination significantly extends the shelf life of dairy products while balancing safety, aesthetic appeal, and processing compatibility, making it a premier choice for high-end dairy packaging.

Core Structure and Material Characteristics

This material employs a multi-layer co-extrusion composite structure. A typical configuration consists of PP (outer layer) / Adhesive Layer / EVOH (core barrier layer) / Adhesive Layer / PP (inner layer), with the total thickness precisely controlled at 1.0mm. The functions of each layer work synergistically to complement one another:

**Outer PP Layer:** Provides excellent mechanical strength, impact resistance, and printability. It enables high-definition graphic printing—enhancing product shelf visibility—while withstanding the compression and abrasion encountered during storage and transportation to prevent packaging damage.

**Inner Food-Grade PP Layer:** In direct contact with the dairy products, this layer is non-toxic, odorless, and resistant to acid and alkali corrosion, fully complying with food-contact safety standards. Furthermore, it possesses excellent heat-sealing properties, allowing for a secure seal with compatible lidding films to effectively prevent leakage.

**Intermediate EVOH High-Barrier Layer:** Serving as the core protective layer, EVOH (Ethylene-Vinyl Alcohol Copolymer) leverages the dense hydrogen-bond network within its molecular chains to deliver exceptional barrier performance against oxygen, moisture, and odors. Its oxygen-barrier capability is more than 10,000 times greater than that of pure PP material, far surpassing the performance of conventional materials such as PE or PA. ==========================

1mm Rigid PP Sheet with EVOH High-Barrier Film: The Preferred Solution for Food-Grade Dairy Blister Packaging—Extending Dairy Product Shelf Life

Dairy products such as yogurt and fermented milk are rich in proteins, fats, and active probiotics. Oxygen, temperature, and moisture are the primary factors responsible for their spoilage. This material achieves a significant extension of shelf life through a triple-layer protection mechanism:

Oxygen Barrier Protection: The EVOH layer maintains the oxygen concentration within the packaging at below 0.5%. This significantly reduces the rate of lipid oxidation and minimizes vitamin loss, while simultaneously inhibiting the aerobic proliferation of microorganisms—such as *E. coli* and lactic acid bacteria. Consequently, the shelf life at ambient temperature is extended from 3–7 days to 2–6 months, and the refrigerated shelf life can be extended by more than 1–2 times.

Moisture Barrier Protection: The material's low water vapor transmission rate prevents dehydration and shrinkage of dairy products, thereby preserving their delicate texture. Furthermore, it prevents bacterial growth caused by condensation on the inner walls of the packaging, ensuring consistent product quality.

Temperature Resistance: The thermal stability of the rigid PP substrate is fully compatible with the entire processing and storage lifecycle of dairy products. It prevents packaging deformation and barrier layer failure caused by temperature fluctuations, thereby further reinforcing the product's freshness and preservation.

Suitability for Blister Forming Processing

The 1mm-thick rigid PP sheet combines both rigidity and toughness, making it perfectly suited for vacuum blister forming and thermoforming processes:

Superior Formability: 

Production Line Compatibility: 

Cost-Effectiveness: 

This material is widely applicable to various types of blister packaging for dairy products—including shelf-stable yogurt, refrigerated yogurt, fermented milk, puddings, cheese cups, and more—and is particularly well-suited to meet the dual requirements of high-end brands regarding packaging safety, shelf life, and aesthetics.