Applications of Tosoh Nipoflex 680 EVA in Industrial Manufacturing

Tosoh Nipoflex 680 EVA serves as an essential ethylene-vinyl acetate copolymer for several specialized downstream applications across plastics conversion, solar module production, footwear compounds, and cable insulation. Our manufacturing experience optimizes this raw material for consistent processing and compliance with stringent industry norms.

1. Solar Photovoltaic Module Encapsulation

EVA 680, with its controlled vinyl acetate content and stable melt flow, is specified for encapsulant sheets in crystalline silicon solar modules. Manufacturers rely on its transparency, weatherability, and strong crosslinking response during lamination processes. The material must meet long-term photovoltaic durability and strict electrical safety targets, driving adoption in high-volume module assembly plants.

Industry compliance standards

• UL 1703: Standard for Flat-Plate Photovoltaic Modules
• IEC 61215: Design Qualification and Type Approval
• IEC 61730: PV Module Safety Qualification
• China GB/T 9535-1998 for EVA Films in PV
• RoHS Directive EU 2011/65/EU compliance

Typical usage ratio

• Main resin for encapsulation: 65-75% by weight of film formulation
• Ratio is tuned based on cross-link agent and film adhesiveness—modulated to achieve >80% gel content after lamination

Downstream process integration

• First enters sheet extrusion, pellet blending with peroxide accelerator and UV absorbers
• Film rolls undergo precision calendering for controlled thickness
• Installed in PV module layup stack before vacuum lamination

Final product types

• Encapsulant films for PV modules
• Bifacial solar module sheets
• Back contact and half-cell module encapsulation layers
• Photovoltaic glass-glass module films

2. Hot Melt Adhesives for Packaging and Bookbinding

EVA 680 provides a balance of flexibility and adhesion for hot melt adhesive systems, especially in automated packaging lines and bookbinding manufacturing. Its melt characteristics suit both continuous extrusion adhesive systems and slot die coating lines. Correct polymer architecture secures bond strength to varied substrates and enables formulation adjustment for peelability or permanence.

Industry compliance standards

• FDA 21 CFR 175.105 (Adhesives in Food Packaging)
• REACH Regulation (EC 1907/2006)
• EN 923: Adhesives—Terms and Definitions
• GMP Regulation (EU) No 2023/2006 for food-contact packaging adhesives

Typical usage ratio

• EVA copolymer content: 20-45% of total adhesive formulation by weight
• Adjust with tackifier (hydrocarbon or rosin ester) and plasticizer for viscosity control

Downstream process integration

• Palletized EVA enters adhesive reactor together with resins and waxes
• Compounding under controlled shear to attain desired viscosity (180-220°C)
• Molten adhesive delivered to in-line slot or bead applicators

Final product types

• Case and carton sealing adhesives
• Perfect binding glues for books
• Label stock bonding adhesives
• Flexible and rigid paper packaging production adhesives

3. Injection-Molded Footwear Midsoles and Outsoles

Ethylene-vinyl acetate grades like 680 are formulated for expanded and solid midsoles and outsoles in sports, leisure, and safety shoes. Controlled vinyl acetate content offers both resilient cushioning and abrasion resistance. Customers use the material in direct injection or compression molding, where product uniformity and mechanical performance demand controlled compounding and precise mold flow.

Industry compliance standards

• ISO 20871:2018—Footwear Outsoles—Abrasion Resistance
• EN ISO 20345 for safety shoes (mechanical standards)
• REACH Annex XVII for restricted substances
• RoHS for low-toxic footwear production (children’s shoes)

Typical usage ratio

• Primary EVA resin: 60-90% by weight of compound
• Foaming agents and crosslinkers included at 3-7% and 1-2%, based on hardness and expansion targets

Downstream process integration

• EVA pellets loaded in twin-screw extruder or internal mixer
• Compounded with pigment, foaming/blowing agent, and filler (CaCO₃ or silica)
• Melted compound injected or compressed into outsole/midsole molds at 140-180°C

Final product types

• Running shoe midsoles
• Cushioned slippers and sandals
• Antistatic and oil-resistant safety shoe soles
• Children’s footwear components

4. Cable Sheathing and Wire Insulation

EVA 680 is incorporated as a base polymer in low-voltage cable sheath and insulation compounds. Its flexibility and dielectric properties enable use in electrical wire insulation where performance under bending and environmental stress is crucial. Formulation requires careful mixing with flame retardants, crosslinkers, and lubricants to attain safety compliance and process stability during extrusion.

Industry compliance standards

• IEC 60502: Power Cable Standard
• UL 62 and UL 83: Flexible Cords and Wires
• RoHS Directive (hazardous substances)
• CSA C22.2 No. 49 for flexible cords

Typical usage ratio

• EVA loading: 35-55% of total cable compound
• Proportion adjusted with polyolefin copolymers or fillers to attain target flame resistance and flexibility

Downstream process integration

• Gravimetric blending of EVA with calcium carbonate, aluminium hydroxide, and crosslink initiators
• Melt compound extruded over conductor cores; process set at 120-160°C
• Secondary cross-linking or irradiation step for improved mechanical and thermal properties

Final product types

• Low-voltage power cable jackets
• Flexible wire insulation for consumer electronics
• Outdoor and automotive electrical wire coatings
• Control cable sheaths

5. Flexible Film and Sheet Production

Producers of transparent or colored films specify this grade in flexible packaging and agricultural film production. Its processability yields uniform gauge, clarity, and seal strength, with tailored anti-blocking and slip characteristics as required by end-use. Film lines utilize it where both optical properties and puncture resistance must meet market and food safety standards.

Industry compliance standards

• FDA 21 CFR 177.1350: EVA Copolymers for Food Contact
• EU Regulation No 10/2011: Plastics in Food Contact
• ISO 4591: Plastics—Film Determination of Thickness
• China GB 4806.7-2016 for food-packaging plastics

Typical usage ratio

• EVA main polymer content: 30-70% of total film blend depending on haze and flexibility targets
• Adjusted with LDPE or LLDPE for balance of cost and strength

Downstream process integration

• EVA pellet feedstock enters blown or cast film extrusion lines
• Blending with anti-block masterbatch and slip additives during melt compounding
• Film downgauged and wound for inline quality control testing

Final product types

• Food storage bags and wraps
• Greenhouse and mulch agricultural films
• Stationery and office supply sheets
• Protective surface wrap films