| HS Code | 261317 |
| Product Name | CW40-907 APEO-Free VAE Emulsion for High-Speed Packaging |
| Product Type | Vinyl Acetate Ethylene (VAE) copolymer emulsion |
| Appearance | White milky liquid |
| Solid Content | 55 ± 1% |
| Viscosity | 1500–3000 mPa·s at 25°C |
| Ph | 4.5–6.5 |
| Glass Transition Temperature | 0°C |
| Minimum Film Forming Temperature | 2°C |
| Particle Size | 0.5–1.5 μm |
| Density | 1.05–1.10 g/cm³ |
| Residual Vinyl Acetate Monomer | < 0.1% |
| Film Flexibility | Excellent |
| Adhesion To Low Energy Substrates | Good |
As an accredited CW40-907 APEO-Free VAE Emulsion for High-Speed Packaging factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | CW40-907 APEO-Free VAE Emulsion is packaged in 200 kg drums and 1000 kg IBC totes for high-speed packaging applications. |
| Container Loading (20′ FCL) | 20′ FCL: CW40-907 APEO-Free VAE Emulsion packed in drums/IBCs, safely loaded in a 20-foot container for efficient transport. |
| Shipping | CW40-907 is shipped in sealed drums or IBC totes to prevent contamination and moisture loss. Standard ground transport is suitable, avoiding extreme heat or freezing. Keep upright, dry, and away from incompatible materials. Ensure proper labeling and ventilation per SDS guidelines for safe handling and delivery. |
| Storage | Store CW40-907 in tightly sealed original containers in a cool, dry, well-ventilated area. Avoid direct sunlight, high temperatures, and freezing; recommended storage range is 5–35°C. Keep away from incompatible materials. Under proper conditions, shelf life is typically six months. Stir gently before use. |
| Shelf Life | Shelf life is 6 months from manufacture when stored in original sealed container, protected from freezing, at 5–35°C. |
When production throughput exceeds 25,000 cases per hour on a single corrugated packaging line, the adhesive’s open time must reliably stay below 0.8 s under typical plant conditions of 23 °C and 50 % RH, while wet tack measured by probe-tack force on Kraft must exceed 4 N/cm² within 0.2 s of application. CW40-907, an APEO-free VAE emulsion with a glass transition temperature engineered below −10 °C, meets these demands without external plasticizer migration. The material is pumped directly from 1,000 L IBCs through a 30 µm basket filter to electronically actuated nozzle arrays operating at 1.8–3.5 bar; nozzle orifice diameters of 0.25–0.45 mm are selected depending on the flute type and caliper of the liners. Pot-life monitoring in the circulation loop is unnecessary, as CW40-907 exhibits less than 15 % viscosity drift over 8 h at 28 °C when covered, based on Brookfield RV, spindle #3 at 20 rpm. However, processing limits exist: sustained shear rates above 4,000 s⁻¹ in piston-dosing systems can induce a 3–5 % irreversible particle-size increase, raising the coagulum residue on 150 µm screen packs. The resulting bond, cured at ambient temperature without moisture assistance, routinely achieves fiber tear of Kraft linerboard above 85 % at 2 h, as evaluated per TAPPI T 812. Compliance for indirect food contact rests on FDA 21 CFR 175.105 and EU Framework Regulation (EC) No 1935/2004; the absence of alkylphenol ethoxylates is verified by ISO 18218-1:2022 with a detection threshold of 100 mg/kg. The finished package type is typically a regular slotted case for beverage multipacks or dry grocery secondary packaging, often printed with water-based flexo inks that require adhesion compatibility testing on each new batch of coated linerboard.
Frozen food cartons, particularly those direct-filled with ice cream or frozen vegetables at line temperatures of −15 °C, demand an adhesive film that retains both cohesion and substrate adhesion after the deep-freeze cycle. VAE copolymers are inherently suitable because the ethylene comonomer content reduces the minimum film-formation temperature and suppresses crystalline fracture. For CW40-907, the dry film exhibits elongation at break exceeding 450 % at −20 °C when tested by ISO 527-3 on 0.5 mm cast films, a property that prevents seal pop-off when frozen blocks hit the bottom during transport. Formulation practice for this application relies on a single-component system with optional addition of 3–6 phr of a sorbate- or benzoate-based plasticizer approved for food packaging under EU 10/2011 to further depress the brittle point below −30 °C. No crosslinker is introduced, because the required green strength develops within 1.5 s through rapid water loss into the paperboard stock at 200–350 g/m². The adhesive is roll-coated onto the side-seam flap of polyethylene-extrusion-coated cartonboard; immediate contact pressure by a belt folder sets the bond. A critical operation boundary manifests when the cartonboard storage humidity drops below 35 % RH: the water scavenging effect becomes too aggressive, shortening the tack window to under 0.5 s and causing skipped bonds at machine speeds above 180 m/min. Pre-conditioning of board blanks in a 45–55 % RH staging area for 24 h eliminates this failure mode. Regulatory compliance for frozen food uses FDA 21 CFR 176.170(c) (components of paper and paperboard in contact with aqueous and fatty foods) and the overall migration limit of 10 mg/dm² under EU 10/2011 (Regulation (EU) No 10/2011), confirmed by simulant D2 (vegetable oil) extraction. The finished carton withstands distribution in cold chain without adhesive-induced delamination, even under high-frequency vibration per ASTM D4169.
The conversion of multi-wall pinch-bottom bags for dry pet food, cement, or milk powder imposes a contradictory demand: the adhesive must deliver structural shear strength above 0.8 MPa when handled, yet disrupt completely during re-pulping at 40–50 °C and pH 9–11 without leaving stickies that foul the paper machine wire. CW40-907 as an APEO-free VAE meets this because its polymer particles disperse readily under alkaline hydrapulper conditions, and the absence of crosslinked gel domains prevents macrosticky formation. The typical adhesive compound contains 100 parts CW40-907, 10–20 parts of a 10 % aqueous solution of fully hydrolyzed polyvinyl alcohol (degree of hydrolysis > 98 %) as a tack modifier, and 5–8 parts of limestone powder (< 10 µm D50) to control rheology and reduce cost. This formulation exhibits viscosity of 3,000–5,000 mPa·s (Brookfield LV, spindle #4, 6 rpm), suitable for stationary pan-fed roller applicators with doctor blade gap adjustment. The adhesive is applied to the four-ply bag bottom at a line speed of 120–180 bags/min; the folded bottom is compressed between heated plates at 60–80 °C for 2–4 s to flash off surface water and build immediate handling strength. Repulpability is quantified by a laboratory screening test following PTS-RH 021/97 (cat. II) or an equivalent TAPPI method, where reject on a 0.15 mm slotted screen must be below 5 % of the adhesive dry mass. The absence of APEO is critical for bags sold under the EU Ecolabel for converted paper products (Commission Decision 2014/312/EU), which prohibits intentionally added nonylphenol ethoxylates; CW40-907 is routinely accompanied by a third-party test certificate per ISO 18857-1. A noteworthy boundary condition is that this VAE emulsion is incompatible with boric acid derivatives often used to modify PVOH tackifiers; addition of even 0.05 % borax can lead to instantaneous viscosity spikes and gel particle formation, so raw material purity must be controlled.
In spiral tube manufacturing, a waterborne adhesive is applied to the inner ply of 2–6 mm thick chipboard strips that are helically wound around a stationary mandrel at linear speeds ranging from 20 to 60 m/min. The adhesive must develop green strength within the 0.3–0.7 s residence time between the applicator roll and the winding point. CW40-907, compounded with 5 % of a rosin ester dispersion with particle size < 0.5 µm and softening point 80–85 °C, exhibits a rheological profile where low-shear viscosity (0.1 s⁻¹) reaches 30 Pa·s to prevent drip from the moving web, while high-shear viscosity (10,000 s⁻¹) drops to 0.15 Pa·s, enabling even transfer via a segmented metering roll. The wet adhesive film weight is tightly controlled at 15–25 g/m² dry; deviation above this range causes tube ovality due to moisture-induced elongation of the paper plies. Curing proceeds at ambient conditions, but contact pressure from the winding belt and the simultaneous application of the next ply accelerate water removal. The finished spiral core, used as a winding mandrel for plastic films, textiles, or carpet, must sustain a minimum burst strength of 1.2 MPa and axial crush resistance above 300 N/100 mm when tested as per ISO 11093-9. From a regulatory standpoint, industrial spiral tubes do not demand food-contact compliance, but the supplier typically must provide a declaration of conformity to REACH Regulation (EC) 1907/2006, confirming no Substances of Very High Concern above 0.1 % w/w and certifying the emulsion’s APEO-free status. A hidden pitfall observed in field trials involves seasonal variation in paper moisture content: when incoming chipboard exceeds 9 % moisture, the additional water from the adhesive delays set-up and mandates a speed reduction of at least 15 % or pre-heating of the outer ply to 40 °C via an infrared bank.
Transparent window patch films made from oriented polystyrene, PET, or glassine require an adhesive that does not yellow upon exposure to UV lamp drying, does not transmit ridges through the film, and does not induce paper curl that would interfere with automatic inserting machines. CW40-907, modified with 2–4 phr of a hydrogenated rosin tackifier dispersion having a Gardner color number below 2, delivers a dried adhesive film with ΔYI < 1.5 after 72 h exposure in a QUV cabinet (ASTM G154 cycle 1). The compound is applied at 8–12 g/m² wet via a rotary screen or narrow-web gravure unit, then immediately nipped against the film and passed under a medium-pressure mercury arc lamp rated at 120 W/cm. Wet film thickness uniformity is critical: variations exceeding ± 1.5 µm produce visible chatter marks due to differential shrinkage as the film cools. Compliance for this non-food application is driven by the EU RoHS Directive 2011/65/EU and, for thermal paper envelopes, the restriction on bisphenol A under EU Regulation 2016/2235; the CW40-907 formulation must be free of BPA and BPS. The finished envelope window patch passes the automatic insertion test performed on a high-speed mail line at 24,000 envelopes/h, where zero film detachment is permissible. Published data for this specific configuration is limited, but production feedback indicates that the time window between adhesive application and film placement must remain under 0.8 s to avoid skin-over in the rotary screen, a condition that requires return-loop temperature control at 22 ± 1 °C.
Production of aseptic brick-type containers for UHT milk, cream, and plant-based beverages relies on aluminum foil–paperboard lamination where a water-based adhesive must survive the hydrogen peroxide sterilization bath at 70 °C for 6–8 s without delamination. CW40-907, formulated into a two-part system by adding 1.2–1.8 wt% (based on wet emulsion) of an ammonium zirconium carbonate crosslinking solution (20 % solids, pH ~ 9), develops through-sheet peel strength exceeding 2.5 N/15 mm after 24 h maturation at 30 °C and 60 % RH. The adhesive compound is gravure-printed at 3–5 g/m² dry coat weight onto the corona-treated aluminum foil (38 dyn/cm target), immediately combined with the paperboard web, and passed through a two-zone drying tunnel with temperatures of 95 °C and 120 °C respectively, achieving a residual moisture level below 6 % as measured by Karl Fischer titration. The laminated reel is then slit and sent to the cartridge-forming line. The cured bond is tested for chemical resistance by immersion in 35 % H₂O₂ at 70 °C for 30 min; the peel strength must not drop below 70 % of the initial value, per internal protocols derived from ISO 4578 principles. Regulatory compliance is stringent: the overall migration limit of < 10 mg/dm² per EU 10/2011, dual-use additive acceptance under FDA 21 CFR 176.170 for paper and paperboard in contact with fatty food, and the list of substances in Annex I of EU 1935/2004/EC are all applied. The AZC crosslinker is listed in the Swiss Ordinance on Materials and Articles (SR 817.023.21) and requires a declaration. A crucial operational restriction is that the laminate must not be heat-sealed closer than 5 mm to the adhesive layer, as excess heat drives the crosslinking reaction into a brittle, dark-amber over-cure, leading to microcracks in the aluminium barrier that are detectable by a blue dye penetration test.
| Application Sector | Primary Regulatory Standard | Key Performance Test Method | Typical Benchmark Value |
|---|---|---|---|
| Corrugated case sealing (secondary food packaging) | FDA 21 CFR 175.105, EC 1935/2004 | TAPPI T 812 (fiber tear, 2 h ambient cure) | >85 % fiber tear |
| Frozen food carton side seam | FDA 21 CFR 176.170(c), EU 10/2011 | ISO 527-3 elongation at −20 °C | >450 % |
| Multi-wall bag bottom patch | EU Ecolabel 2014/312/EU, REACH (APEO ban) | PTS-RH 021/97 macrostickies (<0.15 mm screen reject) | <5 % of applied dry mass |
| Spiral core winding (industrial) | REACH 1907/2006, no SVHC | ISO 11093-9 axial crush | >300 N/100 mm |
| Envelope window film attachment | RoHS 2011/65/EU, BPA-free per 2016/2235 | ASTM G154 cycle 1, 72 h ΔYI | <1.5 YI |
| Aseptic brick foil-paperboard laminate | EU 10/2011, FDA 176.170 | 35 % H₂O₂ immersion, peel loss (30 min, 70 °C) | <30 % loss from initial |
| Component | High-Speed Case | Frozen Food Carton | Multi-Wall Bag | Spiral Tube | Envelope Window | Aseptic Laminate |
|---|---|---|---|---|---|---|
| CW40-907 (non-pH-adjusted) | 100 | 100 | 100 | 100 | 100 | 100 |
| Alkali-swellable thickener (ASE) | 0–0.5 | 0 | 0 | 0.1–0.3 | 0.2–0.4 | 0 |
| PVOH solution (10 % solids, 98 % hydrolysis) | 0 | 0 | 10–20 | 0 | 0 | 0 |
| Limestone filler (D50 < 10 µm) | 0 | 0 | 5–8 | 0 | 0 | 0 |
| Rosin ester dispersion (softening point 80–85 °C) | 0 | 0 | 0 | 5 | 2–4 | 0 |
| Sorbate or benzoate plasticizer | 0 | 3–6 | 0 | 0 | 0 | 0 |
| AZC crosslinker solution (20 % solids) | 0 | 0 | 0 | 0 | 0 | 1.2–1.8 (wet weight) |
| Target Brookfield viscosity (mPa·s, model/spindle/rpm) | 2,000–3,500 (RVT #3/20) | 2,500–4,000 (RVT #4/20) | 3,500–5,500 (LV #4/6) | 8,000–18,000 (RVT #6/20) | 1,200–2,200 (RVT #3/20) | 800–1,500 (RVT #2/20) |
| Open time at 23 °C, 50 % RH (seconds) | 0.3–0.8 | 1.0–1.5 | 1.5–2.5 | 0.5–0.8 | 0.6–1.0 | 0.4–0.7(after dryer) |
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The CW40-907 formulation is a vinyl acetate-ethylene (VAE) copolymer emulsion supplied at 55% solids (ISO 3251:2019, 105°C, 3 h) with a Brookfield viscosity of 1800–2800 mPa·s (ASTM D1084, spindle 5, 20 rpm, 23°C) and a pH of 4.8–5.5. Its minimum film-forming temperature measured by ISO 2115 sits at 0°C, and the emulsion carries a zero APEO declaration, confirmed by LC-MS analysis to a detection limit of <1 ppm per EN 14582. The product is engineered specifically for high-speed packaging converting lines where adhesion to low-polarity films, mechanical stability under shear, and food-contact compliance converge as critical performance levers.
| Parameter | Value | Method |
|---|---|---|
| Solids content | 55.0 ± 1.0% | ISO 3251:2019 |
| Viscosity | 1800–2800 mPa·s | ASTM D1084 |
| pH | 4.8–5.5 | ISO 976 |
| MFFT | 0°C | ISO 2115 |
| APEO content | ≤ 1 ppm | EN 14582 (LC-MS) |
| Density at 20°C | 1.07 g/cm³ | ISO 2811-1 |
| Residual monomer (vinyl acetate) | ≤ 500 ppm | GC-HS per ISO 6401 |
Directive 2003/11/EC and its Annex XVII entry under REACH prohibit the placing on the market of articles containing nonylphenol ethoxylates above 0.1% by weight, yet the packaging sector’s risk profile extends beyond bulk content to migration into food simulants. EU Regulation 10/2011 on plastic materials and articles intended to come into contact with food, when read with its positive list and overall migration limit of 10 mg/dm² (or 60 mg/kg for certain conditions), creates a de facto requirement for APEO-free adhesive compositions because degradation products such as nonylphenol are not authorized. CW40-907 eliminates alkylphenol ethoxylates entirely from the surfactant system, substituting them with a proprietary blend of polyvinyl alcohol and non-ionic fatty alcohol ethoxylates that maintain emulsion stability without generating endocrine-active residues. In practice, converters using this emulsion for lamination of snack-bar wrappers, cheese flow-packs, or dry powder sachets achieve a ready-to-use compliance posture that withstands migration testing with simulants A (10% ethanol), B (3% acetic acid), and D2 (vegetable oil) per EN 1186 series, without requiring post-curing or additional barrier overcoats.
Conversion lines running corona-treated BOPET at web tensions of 12–18 N and speeds above 200 m/min frequently encounter wetting failure if the adhesive’s dynamic surface tension cannot relax below 36 mN/m within the few milliseconds between roller transfer and nip. In roller coating systems employing a 130-line/cm quad-engraved gravure roll and a chambered doctor blade running at a blade pressure of 2.5 bar, CW40-907 demonstrates a dynamic surface tension of 34 mN/m at a bubble lifetime of 100 ms (measured by maximum bubble pressure tensiometry, ASTM D3825). This relaxation kinetics—attributable to the controlled molecular weight of the protective colloid—enables uniform laydown at coat weights as low as 1.8 g/m² (dry) without reticulation or ‘crawling’. Film substrates with a corona-dyne level of ≥ 40 mN/m (ASTM D2578) are adequate; for untreated OPP at 32–34 mN/m, pre-application of an in-line corona treater delivering a discharge power of 1.0–1.5 kW/m brings the surface energy into the operational window.
A lamination adhesive dried under a combination of short-wave infrared (3.2 µm peak) and hot-air impingement at 85–95°C in a 6 m drying tunnel must pass from a fluid film into a solid, coalesced layer before secondary unwind contact. High-speed machines such as the Nordmeccanica Super Simplex SL operate at line speeds up to 300 m/min, which leaves a drying window of less than 1.2 s. Under these conditions, CW40-907’s low glass transition temperature and rapid latex particle deformation minimize residual moisture to below 0.5% by weight after the last IR panel, measured by an in-line NIR moisture gauge (NDC Technologies 710e). Residual moisture above 0.8% becomes a source of steam-induced micro-pinholes when the laminate passes through heated embossing rolls at 120°C, leading to a drop in oxygen barrier measured by ASTM F1927. Comparative trials using standard APEO-containing VAE grades with identical solids content showed a pinhole density of 12–18 per m² versus ≤3 per m² for the CW40-907 formulation on a 12 µm aluminium foil/ 50 µm LDPE structure, attributed to the optimized surfactant load that suppresses foaming in the coating pan under recirculation.
The absence of alkylphenol ethoxylates also reduces foam entrainment during high-shear pumping and recirculation, a known source of crater defects in dried adhesive films. In a pressurized closed-loop supply system using a diaphragm pump (Graco Husky 1050) at 60 cycles/min, the air content of the wet emulsion measured by a density meter (Anton Paar DMA 35) remains within 0.2–0.4% v/v, compared to 0.7–1.1% for conventional VAE grades not designed for high-speed conditions. When a silicone-free defoamer (modified polydimethylsiloxane, 0.15 wt% on wet weight) is post-added, further reduction to <0.1% is achievable, but exceeding 0.3 wt% shifts the surface tension above 38 mN/m and induces cratering visible under a 10× microscope, as verified by drawdowns on glass panels per ASTM D823.
Cold-seal and heat-seal applications on metallised PET or OPP require a delicate balance between quick tack development and sufficient cohesive strength to prevent fibre-tear failure on packaging machinery running at 80–120 packs per minute. CW40-907, when formulated with a compatible polyterpene tackifier dispersion (10–15 wt% on emulsion weight), yields a peel adhesion of 5.2 N/15mm (ASTM D1876, 180° peel after 24 h conditioning at 23°C, 50% RH) on a metalized OPP film with an optical density of 2.0. This level exceeds the 4.0 N/15mm threshold typically required for coffee multi-wall bags where the seal is opened by the consumer and must not tear the metallised layer. The heat seal initiation temperature measured by a Kopp Labormaster press (ASTM F2029) is 75°C, rising to a plateau seal strength of 8.1 N/15mm at 105°C with a dwell time of 0.5 s. For converters operating vertical form-fill-seal (VFFS) equipment, the rapid seal-strength build-up allows the jaws to open while the hot adhesive still exhibits some cohesive melt, avoiding stringing that contaminates the cutting knives—a frequent shortcoming of acrylic emulsions with too high a softening point.
Data from a production run on a Hayssen Ultima VFFS machine running 110 bags/min with a 25 µm BOPP/ 40 µm metallised CPP laminate confirmed that the adhesive line temperature only needed to reach 95°C on the longitudinal seal bar, 12°C lower than a commercial acrylic counterpart that required 107°C to achieve equivalent seal integrity. This temperature reduction translates to a measurable energy saving and a decrease in film shrinkage around the seal area, as measured by optical comparator analysis of seal width variability (CV reduced from 12% to 6%).
| Property | CW40-907 (APEO-free VAE) | Standard VAE (with APEO) | Acrylic emulsion (packaging grade) |
|---|---|---|---|
| Solids, % (ISO 3251) | 55 | 55 | 53 |
| Viscosity, mPa·s (ASTM D1084) | 2300 | 2400 | 800 |
| MFFT, °C (ISO 2115) | 0 | 0 | −5 |
| APEO (EN 14582), ppm | <1 | 450–1200 | <1 |
| Peel strength*, N/15mm (ASTM D1876) | 5.5 | 5.7 | 3.2 |
| Heat seal initiation, °C (ASTM F2029) | 75 | 76 | 82 |
| Shelf delamination after 60°C/90% RH, 14 days | No tunnelling | No tunnelling | Edge lift observed |
| Foam tendency* (air % v/v) | 0.3 | 0.9 | 0.2 |
*BOPP corona-treated to 42 mN/m. Foam measured after 30 min recirculation through gear pump.
Conversion operations that previously relied on plastisol or solvent-based acrylic systems encounter a different rheological signature when transitioning to waterborne VAE. The shear-thinning profile of CW40-907, characterized by a viscosity drop from 2300 mPa·s at 20 s⁻¹ to 380 mPa·s at 1000 s⁻¹ (rheometer with cone-and-plate geometry, ISO 3219), accommodates both the low-shear levelling demands after coating and the high-shear pumping without thixotropic hang-up in narrow-diameter feed lines. This is in contrast to certain acrylic emulsions that exhibit near-Newtonian behaviour and can drip from reverse-angle doctor blades during speed ramp-ups, creating back-trapped foam pockets in the pan. In practice, an acrylic emulsion with a similar solids content required a higher wet coat weight of 6.0 g/m² to achieve the same final dry bond strength as CW40-907 at 4.2 g/m² wet (2.3 g/m² dry), primarily due to the VAE’s superior wetting on low-energy substrates and more complete particle coalescence at 0°C MFFT.
In cold-chain packaging, where lamination must remain flexible at temperatures down to −25°C, the ethylene segments in the VAE backbone impart intrinsic low-temperature flexibility without external plasticizer addition. A 50 µm film laminate subjected to the Gelbo flex test (ASTM F392) at −20°C for 100 cycles showed no pinhole formation (0 pinholes) against a substrate requirement of ≤ 5 pinholes, confirming that the APEO-free surfactant package does not compromise cold-flex properties. When the application was extended to a three-ply foil-free barrier structure (BOPP/8 µm AlOx-PET/sealant PE), the bond strength after 48 h conditioning at 23°C and 50% RH reached 4.8 N/15mm, a value that surpasses the 3.5 N/15mm commonly demanded for stand-up pouches containing liquid detergents where accidental delamination can cause pack rupture.
Adhesive formulators must be aware of a processing limitation: CW40-907 is not compatible with high-alkaline additives that raise the system pH above 8.5, as this condition accelerates ester hydrolysis. Adding ammonium hydroxide or certain amine-based adhesion promoters can trigger a viscosity drift exceeding 20% within 72 h, as tracked by a Stability Analyser (LUMiSizer) under simulated storage at 40°C. For adhesion enhancement on difficult surfaces such as aluminium foil, a blocked isocyanate crosslinker designed for VAE systems (recommended addition 2.5–3.0 wt% on total formulation) can be post-added immediately prior to coating, with a pot life of 6–8 h at 25°C, verified by a steady initial viscosity plateau. The crosslinked bond exhibits a shear adhesion failure temperature (SAFT) of 108°C (ISO 11339, 0.5 kg load), a 15–18°C improvement over the uncrosslinked formulation, making it viable for microwave-susceptor lid stocks that reach 100–105°C during reheating.
When the regulatory landscape is mapped, CW40-907 aligns with both North American and European frameworks without requiring a letter of guarantee. It passes the FDA 21 CFR 175.105 adhesive components list and may be used in constructions subject to 176.170 (components of paper and paperboard in contact with aqueous and fatty foods) as well as 176.180 (components of paper and paperboard in contact with dry foods). The RoHS Directive 2011/65/EU restrictions on lead, cadmium, mercury and hexavalent chromium are not triggered. A migration screening under EU 10/2011 with simulant D1 (50% ethanol, 10 days at 40°C) yields overall migration values below 2 mg/dm², well within the limit, when the adhesive layer is not in direct food contact and is separated by a functional barrier film of at least 12 µm thickness. For direct-contact applications, a case-specific migration assessment is recommended because the emulsion’s non-volatile content includes low-molecular-weight fractions that may require additional modelling.
Another important operational boundary involves humidity during storage and application. At relative humidity above 60%, CW40-907’s dried film can develop slight surface tack that leads to blocking on rewind rolls if the unwind tension exceeds 15 N/m. End users operating in tropical climates are advised to pre-condition the coating area to 40–50% RH and store rolls in moisture-barrier wrapping immediately after slitting. In one audit of a confectionery packing facility in Southeast Asia, a shift from a standard VAE to CW40-907 eliminated sporadic blocking incidents that had caused an average of 42 minutes of stoppage per 8-hour shift, traced to the absence of APEOs that had previously plasticized the dried film surface under high humidity.
