| HS Code | 595022 |
| Product Name | Covinax 270-10 |
| Material Family | Soft Magnetic Cobalt-Nickel-Iron Alloy |
| Nominal Composition | 27% Cobalt, 10% Nickel, 63% Iron |
| Density | 8.15 g/cm³ |
| Melting Range | 1430-1460 °C |
| Curie Temperature | 850 °C |
| Saturation Flux Density | 2.35 T |
| Electrical Resistivity | 0.45 µΩ·m |
| Thermal Conductivity | 18 W/(m·K) |
| Coefficient Of Thermal Expansion | 5.2 µm/(m·K) (20-200 °C) |
| Ultimate Tensile Strength | 550 MPa |
| Elongation At Break | 30% |
| Hardness | 80 HRB |
As an accredited Covinax 270-10 factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Covinax 270-10 is packaged in 200 kg sealed steel drums, with clear hazard labeling, protected from moisture and stored upright. |
| Container Loading (20′ FCL) | Covinax 270-10 is loaded as a 20-foot full container load, securely packed and braced for safe, efficient chemical transport. |
| Shipping | Covinax 270-10 is shipped as “Adhesives containing flammable liquid” (UN 1133), Class 3. Pack in UN-certified sealed drums or IBCs, grounded and labeled. Keep upright, ventilated, and away from heat, sparks, and oxidizers. Attach SDS and emergency response documentation; follow all applicable dangerous goods regulations. |
| Storage | Store Covinax 270-10 in tightly sealed, original containers in a cool, dry, well-ventilated area away from direct sunlight, heat sources, and incompatible materials. Keep containers upright and protected from physical damage. Avoid freezing and excessive temperatures, which may alter stability. Follow manufacturer guidelines, maintain proper labeling, and use within the recommended shelf life. |
| Shelf Life | Store in original, sealed container at room temperature, away from moisture. Shelf life is typically 12 months from manufacture date. |
Clear pressure-sensitive labelstock on biaxially oriented polypropylene depends on adhesive transparency after lamination and low haze after 24 h dwell. A 100-part charge of Covinax 270-10 is diluted with maximum 5 parts deionized water to a DIN 4 cup viscosity of 25–35 s at 25°C; when pinholes appear on corona-treated film with surface energy above 42 mN/m, 0.05–0.2 parts of a non-ionic wetting agent is post-added under low-shear mixing. The applicable U.S. regulatory reference for the finished label construction is FDA 21 CFR 175.125; EU shipments are evaluated under REACH EC 1907/2006 SVHC disclosure, and the adhesive package is plasticizer-free for low migration risk. Production slot-die coating on a 2,000 mm web width uses a dry deposit of 19–22 g/m²; a three-zone air flotation oven with set points of 70°C, 90°C, and 110°C reduces residual moisture to below 0.5% before lamination to glassine release liner at 3–5 bar. Dilution above 5 parts water produces edge retraction on untreated film and should be avoided unless in-line corona treatment is maintained. The terminal constructions are printed clear or metallized BOPP pressure-sensitive labels for beverage bottles, personal-care packaging, and cold-fill containers.
Direct coating onto thermal-transfer paper facestock at 70–80 g/m² semigloss paper requires strike-through resistance during wet dwell and stable coat-weight uniformity under reverse gravure. A 100-part batch of Covinax 270-10 is adjusted with 0.1–0.5 parts of an associative polyacrylate thickener to a Brookfield RV viscosity of 800–1,200 mPa·s at 20 rpm, followed by 0.05–0.1 parts of a mineral-oil-free defoamer to limit microfoam in the coating pan. Lot release under ISO 9001:2015 is supported by static shear documentation using ASTM D3654/D3654M-06 with a 1 kg load after 24 h dwell; food-contact label customers also trace the finished article against FDA 21 CFR 175.125 and the EU framework Regulation 1935/2004/EC. Reverse gravure coating at 90–120 m/min is run on a 12 m hot-air tunnel with exhaust humidity maintained below 12 g H₂O/kg dry air; paper facestock above 60% RH is pre-dried to prevent curl-induced coat-weight drift and subsequent adhesive strikethrough. Known production bottlenecks include adhesive stringing at the rotary die-cutting station when matrix stripping exceeds 120 m/min, resulting in liner curl, edge adhesive build-up on the anvil, and intermittent label lift at the dispensing edge. Above 0.5 parts thickener, shear viscosity can exceed 4,000 mPa·s and produce ribbing in reverse gravure coating. The terminal articles are variable-information thermal-transfer logistics labels, pallet labels, and barcode identification stickers for warehousing and parcel distribution.
| Standard | Scope | Scenario | Verification Point |
|---|---|---|---|
| FDA 21 CFR 175.125 | Pressure-sensitive adhesive indirect food contact | Beverage and food labelstock | Finished article migration test |
| REACH EC 1907/2006 | SVHC disclosure and chemical phase-out | All constructions | SDS and SVHC certificate |
| RoHS Directive 2011/65/EU | Restricted metals and phthalates | Electronics labels and tapes | XRF or chemical analysis |
| ASTM D3330/D3330M Method A | 180° peel on stainless steel | Tape constructions | 20 min and 24 h dwell |
| ASTM D3654/D3654M-06 | Static shear at 23°C and 70°C | Paper and film labelstock | Failure time at 1 kg |
Carton-sealing tape constructions use 25–30 µm BOPP film with a release-coated opposite face for self-winding. The adhesive is applied at 100 parts Covinax 270-10 with 0.2–0.4 parts of a silicone-free flow agent to assist direct gravure transfer; no external tackifier is required for commercial low-noise unwind. Regulatory compliance is verified under RoHS Directive 2011/65/EU for phthalates and heavy metals, and ASTM D3330/D3330M Method A 180° peel on stainless steel is tested after 20 min and 24 h dwell. The process is direct gravure or reverse gravure at dry coat weights of 18–22 g/m²; the drying tunnel is operated with entry zone air temperature no higher than 70°C, a mid-zone at 85°C, and a final zone at 105°C, because surface skin-over above 110°C traps residual water and produces craters or microblisters in the dry film. At line speeds above 100 m/min, the limiting factor is not mechanical transfer but moisture removal from the adhesive’s coalesced polymer network; if the tunnel exhaust humidity exceeds 15 g H₂O/kg dry air, the film enters self-winding with residual moisture above 0.5%, which manifests as unwind blocking on the jumbo roll. Dry deposit below 18 g/m² produces incomplete surface contact on rough substrates, while above 22 g/m² static shear at 70°C declines because the thicker adhesive layer shifts from interfacial to cohesive failure. The terminal product is clear or brown carton-sealing tape, splicing tape, and general-purpose packaging tape.
Adhesive transfer tape is produced by coating Covinax 270-10 onto a silicone-coated release liner and drying to residual moisture below 0.5% before a second liner is applied over the exposed adhesive face. A 100-part emulsion charge is thickened with 0.2–0.5 parts of an acrylic thickener to a Brookfield RV viscosity of 1,500–2,500 mPa·s at 20 rpm for comma-bar coating; dry film mass is set between 50 g/m² and 75 g/m² when the transfer tape is intended for die-cut gaskets and mounting pads. The relevant tack method is ASTM D6195 loop tack on stainless steel, while high-temperature resistance is documented by ASTM D3654/D3654M-06 static shear at 70°C with a 500 g load. Coating is run on a floating-knife or comma-bar head at 10–25 m/min because thicker unsupported films require longer oven residence; infrared predry at 45–60°C followed by hot-air heating at 90–110°C prevents blistering at the lower liner interface. Dry adhesive mass below 50 g/m² creates edge shrinkage in die-cut parts and insufficient gap-filling on textured mounting surfaces, while mass above 75 g/m² increases cold flow and liner strike-through on extended storage. The terminal constructions include unsupported transfer tape, die-cut adhesive pads for electronics assembly, gasket backing, and printed graphic mounting films.
Calendered or cast PVC films containing monomeric ester plasticizers generate a known interfacial degradation route in which plasticizer diffuses into the dried adhesive layer, lowers its glass transition, and reduces 180° peel and static shear after 7 days at 70°C. Covinax 270-10 is applied at 100 parts without organic solvent; the dry coat weight for PVC decorative laminates is typically 22–28 g/m², and the facestock is corona-treated to 44–48 mN/m immediately before coating. The applicable regulatory portfolio includes REACH EC 1907/2006 SVHC declarations and RoHS Directive 2011/65/EU for phthalates, with peel reported by ASTM D3330/D3330M Method A after 24 h dwell and after 7 days at 70°C. Slot-die coating is preferred over direct gravure for thick PVC film because gauge variation above ±10 µm causes adhesive weight variation in the cross-web direction; the dryer profile is held at 70°C/85°C/100°C to limit plasticizer volatilization and subsequent fogging on the dryer hood. Incompatibility with monomeric DOP/DEHP grades is a known operational boundary; when plasticizer content exceeds 25 phr, published data for this specific configuration is limited and an adhesion-promoting primer may be required before the adhesive can maintain shelf-stable peel. The terminal products are decorative vinyl films for furniture profiles, interior trim, window graphic films, and durable-goods surface decoration.
Polycarbonate and polyester graphic overlay films for industrial control panels demand clean die-cutting edges and stable peel after indoor UV exposure. A 100-part charge of Covinax 270-10 is applied unmodified for indoor overlay constructions; for outdoor exposure, any wetting or light-stabilizer additive is limited to 0.05–0.15 parts and requires compatibility screening because anionic emulsion stability is sensitive to cationic or high-electrolyte additives. The material is slot-die coated on 175–250 µm polycarbonate at a dry adhesive mass of 50–60 g/m²; drying uses an infrared oven with 60°C/80°C/100°C zones to achieve a bubble-free film without stress whitening. Adhesion is tested according to ASTM D3330/D3330M Method A on stainless steel, and the finished overlay is assessed under RoHS Directive 2011/65/EU for final electronics integration. Cationic additives and amine-based thickeners are incompatible with the emulsion and cause coagulation, filter blocking, and surface microgrit in the dried adhesive. The terminal product type is membrane switch graphic overlays, industrial control panel faceplates, and screen-printed polycarbonate decals.
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Covinax 270-10 is an aqueous vinyl acetate-ethylene copolymer dispersion supplied for use as a formulating base in waterborne packaging adhesives, paper-to-paper laminating compounds, and low-temperature heat-seal coatings. The product is delivered as a milky liquid with a solids content controlled at 50.0–52.0 wt% by ISO 3251:2019, a pH of 4.5–5.5 by ASTM E70-19, and a Brookfield LVF viscosity of 2,500–3,900 mPa·s at 25 °C using spindle 3 at 20 rpm under ISO 2555:2018. The dried film exhibits a glass transition temperature onset of -10 ± 2 °C by ISO 11357-2:2020, which places the product between conventional polyvinyl acetate homopolymers and lower-Tg acrylic pressure-sensitive adhesives. The dispersion is stabilized through a mixed anionic/nonionic surfactant system and is normally supplied in drums, totes, or bulk tanker quantities for converter-scale compounding.
| Property | Test method | Representative range |
|---|---|---|
| Solids content | ISO 3251:2019, 2 g, forced-air oven, 150 °C, 1 h | 50.0–52.0 wt% |
| pH | ASTM E70-19 | 4.5–5.5 |
| Brookfield viscosity | ISO 2555:2018, LVF spindle 3, 20 rpm, 25 °C | 2,500–3,900 mPa·s |
| Density | ISO 2811-1:2016, 25 °C | 1.06–1.08 g/cm³ |
| Glass transition temperature, onset | ISO 11357-2:2020, differential scanning calorimetry | -10 ± 2 °C |
| Minimum film formation temperature | ASTM D7306-17 | 0–4 °C |
| Average particle size | ISO 13320:2020, laser diffraction | 0.20–0.45 µm |
| Freeze-thaw behavior | Direct chamber cycling between -5 °C and 20 °C | Not freeze-thaw stable; protect from freezing |
A standard polyvinyl acetate homopolymer film has a glass transition temperature near +30 °C and is brittle at normal converting temperatures unless an external plasticizer such as dibutyl phthalate, triacetin, or a phthalate-free benzoate ester is incorporated. External plasticizer migration remains a known failure mode in film-to-film laminations where plasticizer exudation causes loss of tack, blocking of the adhesive surface, and visible film haze after aging. The ethylene comonomer in Covinax 270-10 disrupts chain packing along the acetate side groups, lowering the glass transition temperature without the use of a fugitive plasticizer. The result is a polymer film that retains flexibility after storage at elevated temperature because the flexibilizing comonomer is chemically bound to the main chain rather than dispersed as a low-molecular-weight additive.
This structural difference is observed on production-scale hot-melt and waterborne coating lines. In a folded-paperbook spine application, a film of Covinax 270-10 dried at 25 µm nominal dry thickness and conditioned at 23 ± 2 °C and 50 ± 5 % RH for 7 days can be folded over a 5 mm mandrel without macroscopic cracking, whereas a heavily plasticized polyvinyl acetate film of equivalent dry thickness loses flexibility after 300 h at 60 °C in a forced-air aging oven. Published data for this exact comparison is limited to supplier technical bulletins and converter qualification records, but the mechanism is consistent with measured glass transition values under ISO 11357-2:2020.
On a high-speed carton-seaming line running at 120 m/min, the dispersion is transferred from a 200 L HDPE tote through a 1.5 in air-operated diaphragm pump to a slot-die applicator with a die gap of 0.15 mm. A wet deposition of 22–28 g/m² on clay-coated paperboard yields a dry adhesive mass of 11–14 g/m² after forced-air drying in three zones maintained at 65 °C, 75 °C, and 80 °C for 3–5 s total exposure. The lower open-time limit occurs when the first chill-roll surface temperature exceeds 40 °C; at that temperature, surface skimming of the wet deposit produces transfer voids and fiber tear only after a dwell time that is too short for reliable compression lamination. The upper open-time limit is approximately 20 s at 23 °C and 40–50 % RH, beyond which wet tack becomes insufficient for polypropylene film lamination without reactivation.
The uncrosslinked film is redispersible or softened under sustained water exposure and should be assigned only to dry-service applications unless a crosslinker is added. For paper-sack bottom laminations requiring water resistance, glyoxal is added at 3–5 wt% based on wet adhesive formulation weight. Glyoxal solution is introduced below the surface of the stirred batch in a 500 kg day tank equipped with a 0.5 kW turbine mixer operating at 500–800 rpm. The addition lowers batch pH from approximately 4.8 to 3.8; a 10 % aqueous sodium bicarbonate solution is then metered to return the batch to pH 5.0. Filtration through a 100-mesh basket strainer before the supply tank removes gel particles generated at the addition point.
The pot life boundary is sharp. A batch held at 25 °C shows a viscosity increase from approximately 3,000 mPa·s to 5,500 mPa·s after 6 h and exceeds 12,000 mPa·s after 8 h. At 35 °C, the same formulation exceeds 10,000 mPa·s in under 3 h. Once the viscosity exceeds 10,000 mPa·s, transfer pumps on narrow-web coaters may cavitate and the slot-die feed pressure can rise above 0.4 MPa, producing discontinuous coating lanes. Batching should therefore be structured so that crosslinker-containing material is consumed within 6 h at normal room temperature. The cured bond reaches measurable water resistance after 7 days at 23 °C and 50 % RH; immersed in water at 23 °C for 24 h, the failure mode is edge feathering rather than bulk delamination when the bonded substrates have not been pre-wetted.
| Criterion | Covinax 270-10 | Solvent-borne acrylic | Polyvinyl acetate homopolymer |
|---|---|---|---|
| VOC content | <5 g/L by EPA Method 24 | >350 g/L | <10 g/L |
| Glass transition temperature | -10 °C | -20 to -40 °C | +30 °C |
| Low-temperature flexibility | Permanent via ethylene comonomer | Inherent | Requires external plasticizer |
| Adhesion to untreated polyolefin | Limited; corona treatment above 38 mN/m recommended | Good | Poor |
| Water resistance uncrosslinked | Low | High | Low |
| Cleanup after uncured processing | Water | Organic solvent | Water |
| Regulatory basis for food-contact use | Verify FDA 21 CFR and REACH documentation for the final compounded adhesive | Subject to solvent residual and extraction compliance | Verify for specific grade |
Covinax 270-10 is not the correct base polymer when the bonded assembly must meet D4 resistance under EN 204:2016 or withstand continuous hydraulic stress. Uncured or lightly crosslinked compositions are suitable for short-term water contact and dry indoor service, but they should not be specified for outdoor joinery, marine laminating, or structural load-bearing wood bonds. For those demands, a two-component crosslinking VAE with higher ethylene content or a reactive hot-melt polyurethane is normally required. The product also does not provide reliable adhesion to substrates with surface energy below 38 mN/m unless a primer or additional adhesion-promoting resin is formulated into the batch.
High-pH formulation environments are a further boundary. When Covinax 270-10 is blended with borax-stabilized dextrin tackifiers or highly alkaline paper coatings, viscosity instability can occur if the final pH rises above 6.0. The dispersion should not be stored in black iron tanks or transferred through unlined steel piping because polyvalent metal ions can destabilize the anionic stabilization system. Recommended storage conditions are 5–35 °C in sealed HDPE or stainless vessels, with mild agitation before use to restore thermal homogeneity. If the product freezes, irreversible coagulum formation may occur; a freeze-thaw loop that produces grit on a 100-mesh screen requires quarantine and batch rejection.
In a heat-seal coating application for aluminum foil laminated to paper, the dispersion is applied by gravure at 3–5 g/m² dry coat weight and dried to residual moisture below 1.0 % by Karl Fischer titration. The heat-seal activation window is 80–95 °C at a jaw pressure of 0.3–0.5 MPa and a dwell time of 1–2 s. Below 80 °C, seal strength drops below 2 N/15 mm by ASTM F88/F88M-21, while above 95 °C the paper substrate may scorch on high-speed form-fill-seal equipment. The same coating is not suitable for retortable pouch structures because the adhesive film softens under 121 °C saturated steam and loses bond integrity before the substrate fails. For dry food packaging, compliance under FDA 21 CFR and REACH must be confirmed for the specific compounded adhesive, because the neat dispersion alone does not automatically confer direct food-contact clearance.
