Developments in High-Density Polyethylene for Packaging

Polypropylene-based resin expanded beads with improved rigidity for use in logistics cushioning applications like packaging materials. The beads have an expanded core layer of polypropylene and a covering layer of linear low density polyethylene (LLDPE). The mass ratio of the core to covering layers is 97:3 to 88:12. The LLDPE has a melting point of 105-130°C and flexural modulus of 120-600 MPa. This composition allows the expanded beads to have a bulk expansion ratio of 5-45 times and provide good rigidity for cushioning applications while preventing damage to packaged items during transportation. The LLDPE covering layer also has lower friction and static force versus PVC, improving grip properties.

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Stretched film made of an ethylene polymer and a nucleating agent, having improved rigidity and gloss compared to conventional films. The film contains 100-2500 ppm of a nucleating agent per 100 parts of ethylene polymer. The nucleating agent enhances crystallization during film processing to improve properties like rigidity and gloss. The film can be produced by melt extrusion molding followed by stretching. The film has a stretching ratio of 2-6 times for reduced neck-in during stretching.

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High-stiff oriented polyethylene film for sustainable packaging applications that provides better stiffness, optical properties, and moisture barrier compared to conventional polyethylene films. The film has a multilayer structure with at least one inner or outer layer made of a specific ethylene terpolymer composition. This terpolymer has a density range of 920-940 kg/m3 and is combined with multimodal HDPE layers. The terpolymer provides improved stiffness and optical properties, while the HDPE layers enhance stiffness and barrier performance. The film is uniaxially oriented to further improve properties like stiffness and gloss. The film can be used as a standalone packaging material or as a substrate in laminates for improved recyclability compared to multilayer structures with BOPET, BOPP, or BOPA films.

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A stretched film for packaging materials that balances rigidity, low shrinkage, and transparency. The film is made from an ethylene resin composition with specific physical properties. The composition has a melt flow rate (190°C, 2.16kg load) between 0.1-5.0 g/10min, density between 935-970 kg/m3, and a melt index (190°C, 2.16kg load) to melt index (190°C, 2.16kg load) ratio I21/I2 between 40-200. This composition allows stretching the film to improve properties like rigidity and low shrinkage without negatively affecting transparency. The stretched film can be used in packaging materials like laminates and bags.

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Laminate structure with improved printability, strength, and environmental friendliness compared to conventional packaging materials. The laminate has a base material stretched in one direction, a heat-sealable polyethylene layer, and a heat-sealable layer made of the same biomass-derived polyethylene. This allows printing on the base layer, which is stretched for rigidity, and has a biomass-derived polyethylene for environmental benefits. The laminate is sealed with the polyethylene layer facing inside.

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A polyethylene multilayer substrate with improved ink adhesion and heat resistance for packaging materials. The substrate consists of multiple layers containing different types of polyethylene, such as medium density, high density, linear low density, and low density. Stretching the multilayer substrate improves its properties for packaging applications. The stretch treatment enhances transparency, rigidity, strength, and heat resistance. The substrate can be printed with ink for packaging labels without deterioration. The multilayer substrate can also be used as the outer layer in a laminate for packaging materials. The laminate contains the polyethylene multilayer substrate, a heat-sealable polyethylene layer, and optionally a barrier layer and adhesion layer. The all-polyethylene laminate improves recyclability compared to using different resins.

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A printed, laminated structure for stand up pouches that provides good stiffness and optical properties while being made entirely of polyethylene for ease of recycling. The structure has two webs, one for the outer pouch surface and one for the inner sealing area. The outer web has a multilayer configuration with an HDPE layer for rigidity separated by a lower density polyethylene layer to optimize stiffness. The inner web also has HDPE for sealing. This balanced HDPE and lower density polyethylene layering in the outer web achieves both stiffness and good optical properties compared to just using thick HDPE.

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Stretched polyethylene film with improved properties for use in monomaterial packaging. The film is made by stretching a polyethylene resin composition that meets specific density, molecular weight, and branching requirements. The stretched film has good balance between rigidity and impact strength. It can be used as a base film in monomaterial packaging where both the base and sealant films are made of polyethylene. This allows recycling of the packaging material as pure polyethylene.

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Laminate with high recyclability, printability and strength for packaging materials. The laminate has a substrate made of stretched polyethylene, like HDPE or MDPE, with a draw ratio of 2-10 times. This provides the required strength and rigidity. The laminate also has a heat seal layer made of the same polyethylene material. The laminate can be recycled as polyethylene since the same material is used for both layers. The stretched polyethylene substrate improves printability compared to regular polyethylene films.

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Recyclable packaging container with reinforced rigidity that uses laminated polyethylene sheets to replace conventional rigid plastic containers while enabling recycling. The container has a body made of stacked front and rear sheets laminated with an inner PE layer, an outer HDPE layer, and an intermediary woven PE layer sandwiched between. This structure provides rigidity comparable to traditional plastic containers but with a simpler manufacturing process using mono-material films. It also enables recycling by separating the laminated sheets compared to fused multi-material containers.

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Polyethylene multilayered film for packaging applications that has good mechanical properties without requiring the film to be oriented, such as high stiffness expressed by their very good tensile modulus. The film comprises an inner layer, an outer layer and a core layer, wherein the layers comprise a specifically selected high density ethylene polymer in the core layer and specifically selected ethylene polymers in the inner layer and outer layer.

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A polyethylene resin composition for stretched base films used in packaging applications. The composition has specific density, melt flow rate, melt tension, and molecular weight distribution properties. Stretched films made from this composition have improved impact strength and rigidity compared to unstretched films. The composition can be inflated or T-die molded, then stretched to create a substrate film for packaging laminates. The stretched film has a minimum impact strength of 12 J/mm.

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Uniaxially oriented polyethylene film that provides superior stiffness with enhanced heat resistance, improved optical properties and preferably also improved barrier properties. The film comprises a multimodal high density polyethylene (HDPE) polymer component, a laminate and an article comprising the polyethylene film, the use of the polyethylene film or the laminate for packaging an article and a food package comprising the polyethylene film or the laminate.

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Polyethylene formulations for blow molded articles like bottles that provide improved barrier properties, toughness, and weight reduction compared to conventional HDPE. The formulations contain a multimodal high density polyethylene (HDPE) with specific density and molecular weight distribution, along with a nucleating agent. The multimodal HDPE has a density of 0.940-0.970 g/cm3 and a low melt index (0.01-1.0 g/10 min) with a high cumulative infrared detector fraction (CDFIR) > 0.27. The nucleating agent is added in trace amounts (1-10,000 ppm). This formulation enables blow molded articles like bottles to have reduced weight while maintaining rigidity, impact resistance, and barrier properties.

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Multilayer film and laminate for high rigidity and high tenacity packaging like flat-bottomed bags. The film has a core layer made from a high density polyethylene (HDPE) resin with a small amount of propylene-ethylene copolymer thermoplastic elastomer (TPE). The TPE improves stiffness without reducing toughness compared to HDPE alone. The film also has a sealing layer and can have additional core layers. The laminate uses this film sandwiched between substrate and adhesive layers. The HDPE/TPE core provides rigidity and the sealing layer prevents delamination. The adhesive has high modulus to match core stiffness.

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Polyethylene multilayer base material with improved heat resistance and ink adhesion for packaging applications. The multilayer structure has three PE layers with increasing indentation elastic modulus and hardness. This provides better heat resistance without shrinking during heat sealing. The multilayer structure also has good ink adhesion for printing. The PE layers contain medium-density PE, high-density PE, and linear low-density PE. Stretching the multilayer improves transparency, rigidity, and strength. The stretched multilayer can be used as a packaging base instead of layering different resins. It has better heat resistance, recyclability, and printability compared to laminates of different resins.

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Packing device that prevents deformation when stacked by improving the rigidity of the load supporting material. The packing device has a central outer wall, connecting outer walls, and connecting inner walls. The connecting outer walls have bending lines to create acute angles with the connecting inner walls. This improves rigidity. An angle holding means prevents the angles from changing during stacking to maintain the rigidity. This prevents deformation of the connecting outer walls when stacked.

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Ethylene-based polymer composition for bottle caps with high rigidity, high stress crack resistance, high fluidity, and low elongation. The composition contains a major component of ethylene polymer meeting certain density, melt flow rate, and viscosity requirements, as well as a minor component of ethylene copolymer containing α-olefins. This two-stage polymerization process balances high density/rigidity from the ethylene homopolymer with high molecular weight/stress crack resistance from the ethylene copolymer.

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A packaging material film with improved rigidity, impact resistance, and low temperature bending resistance compared to traditional packaging films made from a single resin. The film is a composite of a polyolefin resin like polyethylene and a dispersed phase thermoplastic resin like polyamide, polystyrene, or elastomer. The thermoplastic resin is 5-30% by mass of the film. The dispersed thermoplastic phase has a major-to-minor axis ratio of 5 or more in the film direction. This composite structure provides the desired properties without needing adhesives.

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Standing pouch with a shape-retaining member that allows the pouch to maintain the shape of the opening when opened, provides linearity at the cut end, and prevents contents from sticking to the opening. The pouch has a laminate structure with a plastic film layer and a sealant layer. Inside the pouch, a tape-shaped high-density polyethylene (HDPE) with uniaxial stretching is added. This HDPE has a shape-retaining function that allows it to retain deformation like bending and bending. The HDPE is positioned on the innermost layer facing the contents to prevent adhesion issues. The pouch has a front and rear body connected by a bottom film. The bodies seal at the sides and bottom, and the top is sealed after filling. This allows the HDPE to hold the opening shape when opened.

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