| HS Code | 805978 |
| Chemical Composition | Polyvinyl alcohol (PVOH) based water-soluble film |
| Physical Form | Rolled film |
| Water Solubility | Soluble in water, with grades available for cold and hot water dissolution |
| Biodegradability | Biodegradable in aqueous environments (OECD 301 levels) |
| Tensile Strength | Typically 30-60 MPa depending on grade and conditioning |
| Elongation At Break | Typically 150-400% depending on grade and humidity |
| Density | Approximately 1.25 g/cm³ |
| Melting Point | Around 180-200°C (varies with grade and plasticizer content) |
| Glass Transition Temperature | Approximately 40-60°C depending on plasticizer content |
| Optical Transparency | Highly transparent film with good clarity |
| Oxygen Barrier Properties | Moderate oxygen barrier; property varies with thickness and moisture |
| Thickness Range | Usually 15-75 µm (microns), customizable |
| Printability | Can be printed using flexographic and gravure printing methods |
As an accredited MOWIFLEX factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | MOWIFLEX is packaged in 25 kg multi-wall paper sacks with polyethylene liner, palletized and shrink-wrapped for safe transport and storage. |
| Container Loading (20′ FCL) | MOWIFLEX is packed in bags on pallets, loaded into a 20-foot full container load, secured and ventilated to prevent moisture damage. |
| Shipping | MOWIFLEX is typically shipped as a solid powder in sealed multi-layer paper or PE-lined bags. It is non-hazardous and not classified as dangerous goods. Containers must stay dry and protected from moisture exposure. Handle gently to prevent bag damage, avoid dust generation, and store in a cool, ventilated area. |
| Storage | Store MOWIFLEX in a cool, dry, well-ventilated area away from direct sunlight, heat, and ignition sources. Keep containers tightly closed to prevent moisture absorption, which can cause clumping or degradation. Avoid contact with incompatible materials and follow manufacturer guidelines. Use clean, dry equipment when handling to maintain product integrity and stability. |
| Shelf Life | MOWIFLEX should be stored in original, sealed packaging in cool, dry conditions; typical shelf life is 24 months from manufacture. |
Low-pressure ceramic injection molding of alumina microcomponents uses MOWIFLEX as the water-removable backbone binder. The MOWIFLEX powder contains polyvinyl alcohol as the active binder phase. Grade selection is based on residual acetyl content and 4% aqueous solution viscosity; viscosity is characterized by Höppler falling-ball method per DIN 53015 at 20 °C. The powder is pre-dried at 40 °C before compounding if ambient relative humidity exceeds 60%. MOWIFLEX is compounded at 3.0–6.0 wt% of dry alumina powder mass. Premixing in a V-mixer is run for 20 min; the blend is transferred to a heated sigma-blade compounder at 60–70 °C. The formulation includes 1.5–3.0 wt% polyalkylene glycol as fugitive plasticizer and 0.5–1.0 wt% stearic acid as internal lubricant. Mixing continues under closed-lid conditions until torque stabilization; for 52–58 vol% solids loading, equilibrium torque remains below 40 N·m on a 5 L sigma-blade bowl. Feedstock is injection-molded on a low-pressure machine at 0.2–0.6 MPa with aluminum tooling held at 35–45 °C. Green parts are immersed in deionized water at 40 °C ± 2 °C for 8–12 h; mass loss rather than fixed immersion time determines extraction progress. Deionized water extraction above 50 °C can generate steam pockets and surface pits in sections thicker than 5 mm; bath conductivity above 500 µS/cm indicates the need for water exchange. Residual binder is thermally removed in a forced-air furnace ramped at 0.3–0.5 °C/min to 650 °C. Sintering proceeds at 1650 °C for 2 h. Density is measured by ISO 18754:2013, and flexural strength by ASTM C1161-18. Binder ash is controlled because residual ash above 0.1 wt% degrades sintered density. Powder handling occurs in ISO 14644-1:2015 Class 7 cleanliness. The terminal component is a 97.5% relative density alumina microfluidic chip substrate with channels of 0.8 mm width. Published data for this specific configuration is limited; grade-specific feedstock viscosity and debinding rate must be confirmed against the MOWIFLEX technical data sheet.
Aqueous tape casting of glass–ceramic LTCC layers uses 6–10 wt% MOWIFLEX on dry powder mass. The slurry is built with 0.3–0.6 wt% ammonium polyacrylate dispersant and 2–4 wt% polyethylene glycol 400 plasticizer. Borate-based dispersants must be avoided because borate ions complex with hydroxyl groups on the polyvinyl alcohol backbone and can raise slurry viscosity unpredictably. Milling occurs in a zirconia-lined jar with 10 mm zirconia media for 16–24 h. De-aeration is performed under 50 mbar absolute pressure for 30 min. Doctor blade clearance is set at 120–250 µm; carrier speed is 0.5–1.0 m/min. Drying is divided into a first zone at 25 °C and 55% RH for 2 h, then a second zone at 40 °C and 25% RH for 1 h. Slurry shelf life is held to 48 h at 20 °C; viscosity drift beyond 15% of initial value indicates microbiological activity or incomplete dispersant coverage. Green tape is blanked, registered, and laminated at 70 °C and 18 MPa. Tape tensile properties are measured by ASTM D882-18. Surface roughness after binder burnout is held below 0.6 µm Ra to support via-filling with silver conductor paste. The terminal product is a multilayer LTCC dielectric substrate for 5G RF modules. Water-based casting removes toluene and xylene from the process, aligning the coating line with Directive 2010/75/EU VOC emission limits. RoHS compliance is verified under Directive 2011/65/EU Annex II, and SVHC reporting follows REACH EC 1907/2006 Article 33. Thick tapes above 400 µm may exhibit edge cracking during drying; published data for this specific configuration is limited.
Dry compaction of manganese–zinc ferrite cores for high-frequency power conversion uses MOWIFLEX at 0.8–1.5 wt% as a granulation binder. The binder is added as a 10% aqueous solution into a high-shear granulator with impeller speed 250–400 rpm and chopper speed 1500–2500 rpm. The prepared binder solution is used promptly; storage in sealed containers is required above 60% RH. Granulate is discharged through a 500 µm sieve and pressed in a hydraulic uniaxial press at 150–300 MPa using double-action tooling. The granulate is pressed within 4 h of granulation to maintain moisture between 1.5 wt% and 2.5 wt%; drier granulate produces lamination cracks at ejection. Green density is determined by the geometric and buoyancy methods in ISO 18754:2013; values below 2.9 g/cm³ indicate binder migration or press packing defects. Binder removal in air proceeds from 25 °C to 600 °C at 0.5 °C/min. Sintering is conducted at 1320–1380 °C under nitrogen to preserve MnZn stoichiometry. The terminal products are E, PQ, and toroidal cores for switch-mode power supplies. Core loss at 100 kHz, 200 mT, and 100 °C is measured by IEC 62044-3:2000. Restricted substances are checked against Directive 2011/65/EU when cores are integrated into electrical equipment. The granulation parameter range is necessarily narrow: lower chopper speeds produce oversized granules, while binder solution temperature above 30 °C accelerates skinning on the granulator wall.
Feedstock containing 55–60 vol% strontium ferrite and MOWIFLEX at 4.0–6.0 wt% enters injection molding at 65–75 °C. The dominating process conflict is not initial flow, but capillary defect formation during water debinding when wall thickness exceeds 10 mm. Thick sections develop internal water uptake gradients because soluble binder extraction is diffusion-limited. Immersion at 50 °C for 6 h may remove only 60% of the water-soluble fraction at the centerline. Agitated baths and ultrasonic assistance at 40 kHz improve extraction uniformity but increase surface erosion risk on fine features. The practical upper wall thickness for single-step water removal is 8–12 mm; heavier sections require two-stage removal: water immersion at 35 °C for 24 h, followed by thermal debinding to 500 °C at 0.2 °C/min. Green strength after water extraction is measured by ASTM C1161-18 three-point bending. The terminal product is anisotropic bonded ferrite segments for rotary sensor applications. Process capability for this configuration is influenced by binder grade and powder particle size distribution; published data for this specific configuration is limited.
The following compliance matrix consolidates the test designations that govern MOWIFLEX-related process control across the ceramic forming routes.
| Downstream route | Standard or directive | Measurement or control point |
|---|---|---|
| Low-pressure ceramic injection molding cleanroom powder handling | ISO 14644-1:2015 | Air cleanliness class for powder contact zones |
| Sintered advanced ceramic density and apparent porosity | ISO 18754:2013 | Buoyancy and geometric density comparison |
| Green flexural strength of advanced ceramic carriers | ASTM C1161-18 | Three-point bending of green body |
| Thin ceramic tape tensile properties | ASTM D882-18 | Tensile strength and elongation of thin film |
| MnZn ferrite core loss | IEC 62044-3:2000 | Power loss under specified flux density |
| Bonded abrasive safety marking | EN 12413:2019 | Burst resistance and marking provisions |
| VOC emission from coating line | Directive 2010/75/EU | Solvent emission limit and abatement |
| SVHC communication | REACH EC 1907/2006 | Article 33 supply chain information |
| Restricted substances in electrical equipment | Directive 2011/65/EU | Annex II Pb, Cd, Hg, Cr(VI), PBB, PBDE limits |
Cordierite honeycomb extrusion uses MOWIFLEX at 4–7 wt% in a paste containing 2–4 wt% methylcellulose and 28–31 wt% deionized water. Mixing is performed in a double-arm mixer under vacuum of −0.08 MPa to reduce entrapped air; the mixed paste is aged at 20–25 °C and 85–90% RH for 12–24 h. Extrusion through a 400 cpsi die with wall thickness 0.165 mm requires green yield stress above 80 kPa; channels collapse under self-weight when this threshold is not reached. Die land length is maintained at 3:1 to 5:1 relative to slot width to stabilize wall formation. Drying is staged through 40 °C/80% RH, 60 °C/50% RH, and 90 °C/20% RH to minimize differential shrinkage. Binder burnout to 650 °C is ramped at 0.1–0.3 °C/min because exothermic peaks in sub-0.2 mm walls initiate cracking. Sintering at 1410–1430 °C produces cordierite with a thermal expansion coefficient of 1.0–2.0 × 10⁻⁶ K⁻¹ from 25 °C to 800 °C, measured by ISO 17562:2001. Dimensional control of channel pitch is verified by ISO 1101:2017. The terminal product is a thin-wall cordierite honeycomb substrate for diesel oxidation catalysts or diesel particulate filters. RoHS restrictions are not the primary compliance burden; emissions performance is instead governed by the engine certification framework applicable to the finished vehicle.
For aluminum oxide and silicon carbide abrasive wheels, MOWIFLEX is introduced at 2.0–5.0 wt% as a temporary binder. Abrasive grain and vitrified bond frit are wetted in a rotating pan granulator with a 10–15% MOWIFLEX aqueous solution. The dried granulate is cold-pressed in segmented tooling at 30–80 MPa; pressure is held for 5–10 s to permit binder redistribution. Green wheels are air-dried at 25–30 °C for 24 h, then oven-dried at 90–100 °C until moisture falls below 0.1 wt%. Binder burnout before vitrification is ramped to 600 °C at 0.2–0.5 °C/min in an oxidizing atmosphere. Residual carbon after burnout is held below 0.05 wt% by combustion analysis. Vitrification proceeds at 900–1000 °C depending on frit chemistry. Finished wheels are checked for burst resistance and marking per EN 12413:2019. The terminal products are 125–500 mm diameter wheels for surface grinding of bearing steel. The water-based binder system reduces volatile organic compound release during pressing compared with solvent-borne phenolic binders; extraction air is engineered to ISO 14123-1:2015 for reduction of hazardous substances from machinery.
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MOWIFLEX is a flexible mica paper laminate manufactured from uncalcined muscovite or calcined phlogopite mica paper impregnated with a methyl-silicone resin binder and reinforced on one or both sides with electrical-grade glass cloth. The product is supplied in thicknesses from 0.15 mm to 0.80 mm and in roll widths up to 1200 mm; sheet stock is available at 1000 mm × 2000 mm. Typical resin content is 15 wt% to 25 wt%, and volatile content after 2 h at 150 °C is specified as ≤ 1.0 wt% when tested in accordance with IEC 60371-3-1. The cold flexibility limit is below 10 °C, at which the product can be wrapped around a mandrel of 10× nominal thickness without cracking. The product is intended for use as conductor insulation, slot cell liners, and form-wound coil groundwall reinforcement in rotating electrical machines rated up to 15 kV class. Because the silicone binder remains thermoplastic above 40 °C, preheating to 35 °C to 45 °C is recommended before wrapping to reduce springback; however, overheating above 60 °C causes binder tack transfer to winding tooling and increases wrinkle formation on short-radius bends.
The reinforcement architecture distinguishes MOWIFLEX from films and papers. The glass cloth is a plain-weave fabric with areal weight 23 g/m² to 100 g/m² and is bonded to the mica paper by the same silicone resin that impregnates the mica paper. In comparison with polyester film laminates, MOWIFLEX has lower cut-through resistance at room temperature but higher thermal endurance; in comparison with aramid paper laminates, MOWIFLEX has lower tensile strength after resin impregnation but lower partial discharge erosion when assessed by erosion depth under IEC 60270 for 100 h. Selection between these products is determined by the slot fill factor and the voltage stress distribution, not by single-property ranking.
The continuous operating temperature is governed by the thermal endurance classification of the mica paper and the methyl-silicone binder system. MOWIFLEX grades based on muscovite mica paper with high-resin silicone binder are assigned Class F 155 °C under IEC 60085, while phlogopite mica paper grades with elevated silicone resin content are assigned Class H 180 °C. The limiting mechanism is oxidative scission of the silicone network at the mica-paper interfaces, not dielectric failure of the mica platelets themselves. Long-term thermal ageing data generated on similar silicone-bonded mica laminates show tensile strength retention of 50 % after 20 000 h at 180 °C when the glass cloth reinforcement is present; unreinforced mica paper does not maintain mechanical integrity because resin embrittlement progresses inward from exposed edges. Published data for MOWIFLEX-specific ageing under combined thermal and partial discharge stress is limited, so accelerated ageing should follow IEC 60216-1 and IEC 60216-5 with end-point criteria based on insulation resistance and dielectric strength, not visual colour change alone.
Processing windows during vacuum-pressure impregnation require control of the resin tank temperature within ± 5 °C of the resin manufacturer’s nominal viscosity point. For epoxy-anhydride systems with initial mixed viscosity 75 mPa·s to 125 mPa·s at 23 °C, MOWIFLEX absorbs resin primarily through capillary channels between mica platelets. If tank temperature drifts below 18 °C, resin viscosity rises above 200 mPa·s and interstitial filling becomes incomplete, leaving voids that increase partial discharge inception voltage scatter by up to 30 %. If tank temperature exceeds 28 °C for more than 4 h, the silicone binder migrates into the resin bath and changes the bath’s gel time from 60 min to 20 min. Production-scale VPI equipment with continuous resin filtration and 100 µm bag filters is specified because mica dust released during wrapping can accumulate in the tank and reduce the electrical strength of the impregnating resin. After impregnation, curing in a nitrogen-pressurised autoclave at 0.3 MPa to 0.6 MPa and 140 °C to 160 °C for 6 h to 10 h is required to reach a dissipation factor below 0.05 at 1 kV when tested under ASTM D150.
Batch-to-batch variance in MOWIFLEX is controlled by the mica paper basis weight and the resin coating line speed. On production-scale coating lines with web widths of 1000 mm and speeds of 8 m/min to 15 m/min, variations in oven temperature of ± 3 °C at the 120 °C to 150 °C drying zones cause resin surface skinning that increases volatile content and reduces interlayer adhesion after lamination. The product should therefore be inspected for thickness profile across the web; edge-to-centre thickness deviation greater than 10 % of nominal thickness can lead to uneven compression during coil pressing and create low-density zones at the slot wall.
Electrical withstand of MOWIFLEX is determined by mica platelet orientation, resin impregnation level, and the presence of glass cloth. Short-time dielectric strength on 0.25 mm sheet tested in oil conforming to ASTM D149 is typically 22 kV/mm to 25 kV/mm for muscovite grades and 20 kV/mm to 23 kV/mm for phlogopite grades. Volume resistivity measured at 500 V DC per ASTM D257 exceeds 1 × 1014 Ω·cm at 23 °C and 50 % relative humidity. Partial discharge resistance measured under IEC 60270 on a wrapped electrode configuration is superior to aramid-fibre laminates of equivalent thickness because mica platelets form a high-aspect-ratio barrier layer with tortuous path length. The glass cloth reinforcement is not the primary discharge barrier; it functions as a handling and bridging layer, and its presence lowers the discharge inception voltage by 5 % to 10 % when compared with unreinforced mica paper. Therefore, coil designers place the glass side away from the slot wall and preserve the mica-rich face toward the copper conductor.
| Model | Mica type | Reinforcement | Thickness range | Resin content | Thermal class |
| MOWIFLEX 200 | Muscovite | Glass cloth one side | 0.15 mm – 0.50 mm | 15 wt% – 20 wt% | 155 °C |
| MOWIFLEX 210 | Muscovite | Glass cloth both sides | 0.20 mm – 0.60 mm | 18 wt% – 25 wt% | 155 °C |
| MOWIFLEX 300 | Phlogopite | Glass cloth one side | 0.25 mm – 0.80 mm | 20 wt% – 30 wt% | 180 °C |
| MOWIFLEX 400 | Muscovite or phlogopite | Polyester film with glass cloth | 0.25 mm – 0.75 mm | 15 wt% – 25 wt% | 155 °C |
Nominal values represent manufacturer datasheet ranges and are verified by IEC 60371-3-1 thickness and resin content methods; lot-to-lot variation should be confirmed by incoming inspection.
MOWIFLEX 200 and 300 differ primarily in mica type and thermal class. The phlogopite paper in MOWIFLEX 300 has lower dielectric strength than muscovite paper but withstands higher temperature and has better flexibility; the mica paper basis weight in the 300 series is increased to 120 g/m² to 200 g/m² to compensate for the lower platelet aspect ratio. MOWIFLEX 400 incorporates a polyester film layer for improved moisture barrier and handling stiffness, but the film layer limits continuous operating temperature to Class F 155 °C and reduces resin uptake by approximately 10 % to 15 % compared with the glass-only grades.
Thermal conductivity of mica paper laminates is anisotropic. In-plane thermal conductivity measured by laser flash in accordance with ASTM E1461 is typically 0.25 W/m·K to 0.35 W/m·K, while through-thickness conductivity is 0.15 W/m·K to 0.20 W/m·K. This difference should be used in thermal network models; using a single isotropic value overestimates heat transfer from the copper conductor to the stator core and can underpredict hot-spot temperature by 10 °C to 15 °C in machines above 1 MW.
In resin-rich coil manufacturing, a switch from mica tape to MOWIFLEX sheet is not a direct thickness-for-thickness substitution because the sheet form eliminates overlap regions but increases bending stiffness at conductor corners. Hot pressing of MOWIFLEX at 160 °C with a ramp rate of 2 K/min and a consolidation pressure of 4 MPa to 6 MPa is required to compress the mica paper and expel air from the glass interstices. When press temperature deviates more than ± 5 °C from the target, the silicone binder either does not flow sufficiently to fill the mica paper voids or overcures at the surface and traps volatiles in the core. The resulting insulation can show a two-layer structure with dense outer skins and porous centre, detected by ultrasonic C-scan attenuation increases above 6 dB. In contrast, mica tape processes tolerate a temperature window of ± 10 °C because the open wrap structure allows gas escape during initial heating. For this reason, MOWIFLEX is used in flat slot portions and overlapped only at the end-winding knuckles where mechanical stress is lower, while mica tape remains preferred for continuously transposed conductor stacks that require conformable taping under 15 N to 25 N wrap tension.
Slitting of MOWIFLEX is performed with rotary shear knives set to a gap of 5 % of sheet thickness; dull blades produce edge delamination and release mica dust that contaminates winding halls. A precision guillotine with a clearance of 0.02 mm is specified for sheet cutting. Edge delamination greater than 2 mm from the cut line is a rejection criterion for parts used above 6.6 kV because exposed mica paper edges create a direct path for resin starvation and later partial discharge.
Compared with rigid micanite, MOWIFLEX retains conformability after full cure of the silicone binder because the resin remains thermoplastic and the glass reinforcement limits crack propagation. Rigid micanite products, which use shellac or epoxy hardening binders, exhibit brittle fracture below 5 % flexural strain and require preforming to final shape. MOWIFLEX can be bent to an inner radius of 5× thickness at 23 °C without visible cracking, whereas rigid micanite typically requires heating to 80 °C to 120 °C before forming. However, creep resistance of MOWIFLEX under continuous compressive load is lower than that of rigid micanite; designers should limit continuous slot pressure to 2 MPa to avoid thickness reduction above 5 % after thermal cycling.
Storage before use must avoid relative humidity above 60 %; mica paper adsorbs moisture at the resin-paper interface and can reduce interlayer adhesion during hot pressing. If exposure to high humidity exceeds 24 h, the product should be pre-dried at 80 °C to 90 °C for 2 h to 4 h in a ventilated oven and then conditioned to 35 °C before wrapping. MOWIFLEX should not be installed with amine-based liquid resins that have amine hydrogen equivalent weights below 60 g/eq, because the silicone binder can catalyse early exothermic crosslinking at the laminate surface and produce a low-molecular-weight boundary layer with reduced shear strength.
For applications requiring flame resistance, MOWIFLEX is evaluated by limiting oxygen index under ASTM D2863 and vertical burn classification under UL 94. Typical silicone-bonded mica paper laminates with glass cloth achieve oxygen index above 35 % and do not sustain flame after the ignition source is removed. The mica platelets create a char barrier that reduces smoke release compared with organic polyester film laminates. However, the silicone resin decomposes above 250 °C and releases silicon-containing volatiles; exhaust extraction is required during hot pressing or soldering operations.
| Standard | Test or specification | Application condition |
| IEC 60371-3-1 | Mica paper laminate specification | Thickness, resin content, volatile content |
| IEC 60085 | Electrical insulation thermal evaluation | Class F and Class H assignment |
| IEC 60216-1 | Thermal endurance ageing | Long-term temperature index evaluation |
| IEC 60216-5 | Thermal endurance end-point criteria | Insulation resistance and dielectric strength |
| IEC 60270 | Partial discharge measurement | Discharge inception and erosion comparison |
| ASTM D149 | Dielectric breakdown voltage | Oil immersion short-time test |
| ASTM D150 | AC loss characteristics | Dissipation factor at 1 kV |
| ASTM D257 | DC resistance or conductance | Volume resistivity |
| ASTM D374 | Thickness of solid electrical insulation | Dimensional measurement |
| IEC 60464-2 | Varnishes used for electrical insulation | Compatibility with liquid resins |
In applications where direct liquid cooling is used, the product should be tested for hydrolysis stability under the specific coolant chemistry; published data for ester-based cooling fluids in contact with MOWIFLEX is limited, and extended compatibility testing according to IEC 60464-2 should be performed by the end-user. The glass cloth reinforcement can wick coolant along fibre bundles if edge sealing is incomplete, so cut edges must be sealed with a compatible insulating varnish or overlapping tape before exposure to coolant flow.
