| HS Code | 450151 |
| Product Type | Polyvinyl butyral (PVB) acoustic interlayer |
| Acoustic Performance | High sound damping with significantly improved sound transmission class (STC) and outdoor-indoor transmission class (OITC) |
| Light Transmission | High optical clarity with typical visible light transmission above 90% in clear glass configurations |
| Uv Filtering | Blocks more than 99% of harmful ultraviolet radiation |
| Adhesion To Glass | Strong adhesion to glass surfaces for durability and edge stability |
| Post Breakage Behavior | Retains glass fragments upon breakage, providing enhanced safety and security |
| Impact Resistance | Offers high resistance to impacts and penetrations when laminated |
| Haze Value | Low haze level with a typical value under 1% for excellent visual clarity |
| Thickness Options | Available in standard thicknesses including 0.76 mm, 0.81 mm, 1.14 mm, and 1.52 mm |
| Color Appearance | Clear and transparent appearance suitable for architectural and structural glazing |
| Temperature Resistance | Stable performance across a broad range of environmental temperatures |
| Flexibility | Inherently flexible interlayer material that accommodates thermal glass movement and shaping |
As an accredited Trosifol Sound Control Plus factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Packaged as rolls of acoustic PVB interlayer film in protective cardboard boxes, with quantities typically specified per roll in square metres. |
| Container Loading (20′ FCL) | Trosifol Sound Control Plus is loaded as palletized rolls in a 20-foot FCL, secured and protected from moisture and heat. |
| Shipping | Trosifol Sound Control Plus ships as non-hazardous PVB interlayer rolls on pallets, wrapped in moisture-barrier packaging. Store dry, cool, and flat during transit to prevent deformation. No dangerous goods classification applies, but use covered vehicles and protect from direct heat or humidity until installation. |
| Storage | Store Trosifol Sound Control Plus in its original, unopened packaging in a cool, dry, clean environment. Avoid direct sunlight, heat sources, and excessive humidity. Maintain recommended storage temperatures (typically below 30°C) to preserve performance. Keep rolls horizontal and protected from damage. Use within the stated shelf life, protecting from moisture and contamination. |
| Shelf Life | Store cool, dry, protected from UV. Shelf life is 12 months from date of manufacture in original, unopened packaging. |
In airport terminal façade packages, Trosifol Sound Control Plus is specified as the constrained-layer damping interlayer in the inboard laminate of a double-skin unit. The laminate layup is typically 8 mm heat-strengthened glass / 1.52 mm Trosifol Sound Control Plus / 8 mm heat-strengthened glass, positioned as the inboard leaf with a cavity width of 20 mm to 24 mm filled with dry air or argon. The acoustic requirement is governed by ISO 10140-2:2021, with the relevant expression for air-traffic noise being the weighted sound reduction index w plus the spectrum adaptation term Ctr. Façade specifications near runways typically require Rw + Ctr not lower than 38 dB, although the limiting bands between 100 Hz and 500 Hz are often more difficult to meet than the single-number value.
The interlayer is conditioned at 20 °C to 25 °C and 25 % to 35 % relative humidity for at least 12 h before layup. Glass substrates are washed with demineralized water having conductivity below 20 µS/cm and dried with filtered air at 35 °C to 40 °C. Acoustic PVB exhibits higher plasticizer content and lower melt viscosity than standard PVB, which lengthens the deaeration step and narrows the acceptable autoclave window. Vacuum-bag deaeration is held at 0.1 bar absolute pressure for 45 min to 60 min; for laminates wider than 2 m, a two-stage vacuum ramp is used to prevent air fingers at the trailing edge.
Autoclave processing for terminal façade laminates is constrained between 135 °C and 140 °C, with pressure ramped to 12 bar only after the glass surface temperature exceeds 100 °C. Hold time at peak condition is 60 min for 1.52 mm acoustic PVB. Exceeding 145 °C can produce optical mottle because of localized plasticizer redistribution within the interlayer. Pressure overshoot beyond 13 bar at peak temperature is associated with edge squeeze-out of up to 2 mm, requiring edge trim and increasing the risk of visible edge flow in butt-glazed façade joints. The terminal product is an overhead-impact-rated safety laminate that combines post-breakage retention with acoustic damping in the coincidence region of the laminated glass panel.
OEM windshield qualification for acoustic PVB is driven by two simultaneous requirements: regulatory safety glazing performance under ECE R43 or ANSI/SAE Z26.1-1996, and cabin noise reduction in the speech and high-frequency bands. A representative acoustic windshield layup is 2.1 mm soda-lime glass / 0.76 mm Trosifol Sound Control Plus / 1.8 mm soda-lime glass, giving a nominal total thickness of 4.66 mm. The interlayer thickness is not increased from standard PVB, so the acoustic benefit derives from the viscoelastic response of the interlayer rather than added mass or thickness.
Bent glass pairs are matched and laid up in a clean room maintained at 20 °C to 25 °C and 20 % to 30 % relative humidity. A vacuum ring or channel is applied, and cold deaeration is conducted at 0.05 bar to 0.2 bar for 15 min to 25 min. The pre-nip roll gap is set 0.2 mm to 0.5 mm narrower than the total glass stack. If the gap is too wide, the lower elastic modulus of acoustic PVB permits air fingers to persist along the curved edges; if too narrow, excessive film compression generates edge wrinkles that cannot be recovered in the autoclave.
Windshield autoclave cycles are shorter than architectural cycles because of line throughput constraints. The charge is ramped at 3 °C/min to 5 °C/min to a peak glass surface temperature of 135 °C, with pressure at 11 bar to 12 bar and a hold time of 45 min to 60 min. Acoustic PVB has lower high-temperature viscosity than standard PVB; prolonged soak at 140 °C in curved windshield areas can increase local thickness variation by more than 0.05 mm, altering transmitted optical power and HUD image clarity where a wedge profile is required.
Finished windshields must meet the fragmentation, light transmission, and mechanical strength clauses of ECE R43. Acoustic insertion loss is not a regulatory value but is typically reported by OEM validation programs as an improvement of 2 dB to 4 dB in the 2000 Hz to 4000 Hz bands relative to standard PVB. Published data for Sound Control Plus in specific bent windshield geometries is limited, so each glass-shape and body-sealing configuration requires validation on the actual production line rather than relying on flat coupon data.
Rail vehicle side glazing is governed by EN 15152:2019 for window assemblies and by EN 45545-2:2020 for fire behaviour. Acoustic evaluation follows ISO 10140-2:2021, but the actual forcing spectrum includes structure-borne vibration from wheel-rail interaction, so airborne sound reduction index alone is insufficient. A representative side window layup is 6 mm heat-strengthened soda-lime glass / 1.52 mm Trosifol Sound Control Plus / 4 mm clear glass. The acoustic interlayer is placed against the outer glass leaf to damp flexural waves excited near the coincidence frequency of the 6 mm pane, which typically lies between 2000 Hz and 3150 Hz.
Because rail windows are often curved and may include apertures for emergency hammers or electric heating elements, the interlayer is plotter-cut with a local edge allowance to accommodate flow during autoclave. Layup is performed at 20 °C to 25 °C and 20 % to 30 % relative humidity. Vacuum-bag deaeration is extended to 60 min for curved geometries, and the autoclave ramp is reduced to 2 °C/min to avoid air trapping at tight radii. Peak conditions are 135 °C and 12 bar, with a hold of 60 min to 75 min depending on laminate area.
The dominant lamination failure in curved rail side windows is edge delamination caused by residual stress in chemically strengthened glass and differential thermal expansion during autoclave cooling. Where the edge is exposed to washdown water, a PVB-compatible edge sealant must be applied because moisture ingress reduces peel adhesion and can produce progressive edge whitening. Fire performance under EN 45545-2:2020 is assembly-dependent; the PVB interlayer alters heat release and smoke generation, so a full-scale specimen in the actual frame must be tested. Published data for Sound Control Plus in specific rail hazard level classifications is limited, and compliance cannot be transferred from unframed laminate tests alone.
| Application zone | Governing standard | Acoustic descriptor | Critical lamination boundary |
|---|---|---|---|
| Airport terminal façade | ISO 10140-2:2021, EN 12758 | Rw + Ctr, 38 dB minimum | Autoclave peak 140 °C, 12 bar |
| Automotive windshield | ECE R43, ANSI/SAE Z26.1-1996 | Insertion loss 2 dB to 4 dB at 2000 Hz–4000 Hz | Pre-nip gap 0.2 mm–0.5 mm |
| Rail side window | EN 15152:2019, EN 45545-2:2020 | Rw + Ctr plus structure-borne validation | Curved ramp 2 °C/min |
| Healthcare partition | ASTM E90-09, ASTM E413 | STC 36 to 40 | Relative humidity ≤ 60 % during layup |
| Skylight and canopy | EN 12600, EN 14449 | Impact-noise damping, no single-number descriptor | Edge deletion 8 mm–12 mm at structural silicone |
| Residential window | ISO 10140-2:2021, ISO 16283-1 | Rw + Ctr, field-adjusted | IGU cavity ≥ 12 mm |
Hospital and clinic interior glazing specifications use acoustic interlayers less for façade traffic noise than for speech privacy between examination rooms and corridors. A standard interior partition lite uses 4 mm low-iron glass / 0.76 mm Trosifol Sound Control Plus / 4 mm low-iron glass, giving an 8.76 mm safety laminate that can be installed in aluminium or timber frames with acoustically rated gaskets. The acoustic descriptor is sound transmission class measured under ASTM E90-09 and ASTM E413, or weighted sound reduction index under ISO 10140-2:2021. Healthcare projects commonly specify STC 36 to STC 40, with attention to the 500 Hz to 2000 Hz speech band where closed rooms must limit cross-talk.
Lamination for interior glass follows the same autoclave route as architectural exterior glass but with lower glass thickness and shorter heat soak. Pressure is held at 11 bar to 12 bar and temperature 135 °C for 45 min to 60 min. Acoustic PVB at 0.76 mm is more susceptible to tearing during manual layup than thicker 1.52 mm film; rolls should be cut with dulled blades and handled only by edges. If relative humidity exceeds 60 % during layup, surface tack increases and the risk of air channels near the edge rises, particularly with low-iron glass that reaches higher surface temperatures during subsequent processing.
Interior glazing is inspected for haze according to ASTM D1003; visible haze from residual moisture or adhesive blocking should remain below 0.5 %. Edge squeeze-out is controlled by trimming pre-autoclave overhang to 1 mm; overhang above 2 mm can fold over the glass edge during the pressure ramp and create an optically unacceptable selvedge. The terminal product is a non-fire-rated acoustic safety partition lite. If fire-rated glazing is required, the acoustic PVB interlayer is not a substitute for a listed fire-resistant laminate.
For sloped skylights and canopies, the acoustic problem shifts from airborne sound transmission to structure-borne impact noise from rain and hail. Laminated overhead units built with an acoustic PVB interlayer damp flexural modes of the glass panel and reduce radiated sound below the roof deck. A typical overhead layup is 6 mm heat-strengthened glass / 1.52 mm Trosifol Sound Control Plus / 6 mm heat-strengthened glass, with the interlayer acting as a viscoelastic core under imposed bending after glass fracture.
Overhead glazing is evaluated for post-breakage retention and human-impact safety under EN 12600 and EN 14449; load resistance is calculated according to ASTM E1300 or EN 16612. The acoustic interlayer does not replace structural PVB requirements but contributes to residual load capacity after fracture. Large skylight laminates are laid up on a vacuum table; 1.52 mm acoustic PVB reduces spring-back and improves conformity to curved glass. Deaeration under vacuum reaches 0.05 bar and is held for 40 min to 60 min, followed by autoclave at 135 °C and 12 bar. For laminated glass longer than 3 m, multiple interlayer widths are butt-jointed, and the joint line must be positioned away from drilled holes, edge fittings, and structural sealant contact zones.
Skylight glazing with PVB must not be edge-exposed to standing water. Silicone structural glazing requires edge deletion of the PVB at the sealant interface to prevent plasticizer migration and adhesion loss; edge deletion depth is typically 8 mm to 12 mm for structural silicone contact. The interlayer is also incompatible with amine-containing sealants, which can produce localized softening and optical haze. The terminal product is a curved or flat overhead safety laminate with acoustic damping for rain impact noise; it is not a walk-on glazing product.
Residential laminated glazing retrofits near rail corridors and arterial roads typically use 4 mm / 0.76 mm / 4 mm annealed glass laminates with Trosifol Sound Control Plus in a replacement sash or secondary glazing unit. The acoustic specification is expressed as Rw + Ctr rather than Rw alone, because ground-borne train noise contains significant energy below 500 Hz. A 4 mm / 0.76 mm / 4 mm acoustic laminate reduces noise transmission by adding internal damping without the weight of monolithic 10 mm glass; however, field performance is heavily controlled by frame sealing, perimeter flanking, and wall construction, so site validation under ISO 16283-1 is required.
Window fabricators cut the acoustic laminate with standard glass processing equipment and edge-polish before insulating glass unit assembly. The PVB edge must be protected from cleaning water and assembly solvents; direct contact with aggressive glass cleaners during the post-lamination wash can create visible edge whitening. When the acoustic laminate is used as the inner pane of an insulating glass unit, cavity widths below 12 mm are avoided; a 16 mm to 20 mm cavity is preferred. Low-frequency sound reduction is governed mainly by the laminated panel damping, not the cavity gas fill, so argon fill at 90 % is a thermal measure and does not replace acoustic testing.
The acoustic interlayer does not address flanking sound through the window frame, perimeter sealant, or wall assembly; field sound transmission class values are systematically lower than laboratory ratings. In projects with exterior noise levels above 75 dB Lden, additional glass mass or an independent secondary window is required. The terminal products are residential window sashes or replacement insulating glass units that meet building code safety glazing requirements and provide acoustic damping in the mid- to high-frequency coincidence range.
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Trosifol Sound Control Plus is a polyvinyl butyral interlayer manufactured by Kuraray Trosifol for laminated glass applications in which airborne sound insulation is a specified performance requirement. The material is supplied as a multi-layer calendered film: a central viscoelastic damping core is bonded between two PVB skins. Under flexural vibration generated by incident sound, the core deforms in shear and dissipates energy through hysteresis. This constrained-layer mechanism increases the mechanical loss factor of the laminated pane, particularly near the coincidence frequency where monolithic glass exhibits a sharp reduction in transmission loss. The product is not an acoustic isolator by itself; its performance is a system property of the finished glass build. Acoustic qualification therefore requires testing of the complete laminated configuration—commonly 6 mm glass / 0.76 mm interlayer / 6 mm glass or 8 mm glass / 1.52 mm interlayer / 8 mm glass—rather than testing the interlayer alone. Laboratory sound reduction index measurements are carried out under ISO 10140-2:2021, and rating is derived according to ISO 717-1:2020. In North American specifications, airborne sound transmission loss is measured under ASTM E90 and rated under ASTM E413 for STC and OITC values.
Acoustic improvement is frequency-dependent. The product is most relevant in the 1000 Hz to 4000 Hz one-third-octave bands, where the coincidence dip of glass is mechanically damped. Below 200 Hz, transmission loss is controlled primarily by mass law and pane stiffness, and the damping core contributes little measurable improvement. This operational boundary is critical in traffic-noise and railway-noise dominated façades, where the Ctr spectrum weighting includes substantial low-frequency energy. The interlayer does not remove low-frequency performance gaps caused by poor frame sealing, mullion flanking, or glazing pocket acoustic bridging. Published data for this specific configuration is limited for non-diffuse field and angular incidence conditions.
Standard PVB interlayers are formulated for adhesion, impact retention, optical clarity, and post-breakage resistance. Their acoustic damping contribution is secondary. Sound Control Plus differs in that the central core is formulated with lower shear stiffness in the audible frequency range. The outer PVB skins retain processing compatibility and glass adhesion, while the core increases the constrained-layer damping of the laminated pane. This can shift the coincidence dip and reduce its depth relative to a laminated pane using standard PVB of equivalent thickness. Comparisons of acoustic PVB interlayers and standard PVB generally show weighted sound reduction index improvements of approximately 1 dB to 3 dB in Rw, depending on glass thickness, interlayer gauge, frame conditions, and measurement procedure. This range is not a product-specific guarantee for every build; the improvement must be read against the exact tested pane composition. The interlayer cannot compensate for insufficient glass mass, weak frame systems, or flanking paths.
For material characterization, dynamic mechanical analysis according to ASTM D4065 can be performed on the interlayer or a laminated specimen to establish the temperature- and frequency-dependent loss factor. The complex shear modulus of the core controls the damping response. In a laminated pane, the shift of the coincidence effect is also influenced by the glass thickness and the interlayer shear coupling between the glass plies. ISO 16940:2008 provides a method for measuring the mechanical impedance of laminated glass and can be used to compare the damping behavior of different interlayer formulations. The available published data for Sound Control Plus generally does not include a complete master curve of complex shear modulus across the full service temperature range; when finite-element modeling of façade acoustics is required, the missing dynamic mechanical data should be requested from the manufacturer or generated by laboratory measurement.
Differences from other interlayer products are not limited to acoustic response. Compared with high-strength PVB or ionoplast interlayers used in structural balustrades and point-supported glazing, Sound Control Plus is selected for acoustic damping rather than structural load-transfer performance. In applications such as glass floors, overhead glazing, or balustrades with high post-breakage strength requirements, a structural interlayer should be evaluated separately under the relevant structural glazing standards. The acoustic core alone does not establish compliance with structural load-resistance calculations. Sound Control Plus may also differ from standard architectural PVB in edge-flow behavior during autoclave lamination because the softer core can deform more readily before final crosslinking and glass adhesion are complete. This processing characteristic is discussed in the next section.
Lamination of Sound Control Plus follows the general process logic used for plasticized PVB interlayers, but the softer acoustic core requires attention to pre-lamination conditioning and edge-flow control. Sheet storage should be maintained in a controlled environment with temperature between 18 °C and 26 °C and relative humidity not exceeding 40% before layup. If the film has been exposed to relative humidity above 60% for more than 24 hours, pre-drying under controlled conditions is usually necessary because retained moisture can vaporize during autoclave heating and form bubbles at the glass-interlayer interface. This is not unique to Sound Control Plus, but the multi-layer construction may show edge-zone defects if moisture is unevenly distributed across the roll width.
On heated nip-roller lines, de-airing is commonly conducted at 60 °C to 110 °C depending on glass thickness, nip pressure, and line speed. The nip gap must be set to remove air from the glass roughness profile without squeezing the soft core beyond the glass edge. On vacuum-bag lines, a cold vacuum phase should be held before heating to remove interfacial air; residual pressure below approximately 0.8 bar is typical for PVB lamination, though the exact value depends on glass type, ambient temperature, and vacuum pump capacity. After de-airing, autoclave lamination is generally held at 130 °C to 140 °C and 10 bar to 14 bar for 30 min to 90 min, with the hold time adjusted for load size, glass thickness, and interlayer gauge. Production-scale autoclaves with multiple zone control should be monitored for temperature uniformity; uneven heating can cause localized differences in interlayer flow and acoustic core thickness.
No published data indicates that Sound Control Plus requires a wider autoclave pressure tolerance than standard PVB. However, the softer central layer can produce more visible edge thinning under excessive pressure or temperature. Process qualification should therefore include cross-sectional inspection of the interlayer thickness near the edge after lamination, using a calibrated microscope or optical comparator. Adhesion and durability of the laminated glass are verified under EN ISO 12543-2:2021, and impact safety is verified under EN 12600:2002 or ANSI Z97.1 according to the intended market. In automotive glazing lines where lamination is performed under conformity-of-production requirements, the interlayer should be qualified against the relevant glazing impact tests before bulk production.
In façade applications, a residential traffic-noise specification often requires a laboratory Rw of at least 38 dB for the glazing element. A laminated pane incorporating an acoustic interlayer can raise the transmission loss in the 1250 Hz and 2500 Hz bands compared with standard PVB, but the installed performance is controlled by the frame and building envelope. The following compliance matrix identifies the standards typically used when evaluating Sound Control Plus as part of an acoustic laminated glass product.
| Standard designation | Scope and method | Role in Sound Control Plus qualification |
|---|---|---|
| ISO 10140-2:2021 | Laboratory measurement of airborne sound insulation of building elements | One-third-octave sound reduction index of the full laminated pane |
| ISO 717-1:2020 | Rating of sound insulation in buildings and of building elements | Derives Rw and spectrum adaptation terms from laboratory data |
| ASTM E90 | Laboratory measurement of airborne sound transmission loss | Transmission loss values for North American acoustic specifications |
| ASTM E413 | Classification for rating sound insulation | STC and OITC calculation from transmission loss data |
| EN 12600:2002 | Pendulum impact test for flat glass in buildings | Post-breakage retention and drop-height classification of laminated pane |
| EN ISO 12543-2:2021 | Laminated glass and laminated safety glass requirements | Adhesion, optical, durability, and dimensional verification of the PVB interlayer |
| ISO 16940:2008 | Measurement of mechanical impedance of laminated glass | Comparative damping evaluation of interlayer formulations |
In a laboratory test suite conforming to ISO 10140-2:2021, the test specimen is installed between a source room and a receiving room with suppressed flanking transmission. The sample size is normally not smaller than approximately 1.23 m × 1.48 m, depending on the national annex and test facility. A 10 mm monolithic glass pane exhibits a coincidence dip in the frequency range where the bending wave speed matches the airborne sound speed. Replacing the monolithic pane with a 10 mm laminated pane containing a viscoelastic acoustic interlayer shifts and damps the coincidence response. The transmission loss curve becomes flatter in the 1000 Hz to 4000 Hz region, while the low-frequency performance remains governed by surface mass and panel stiffness. This is why acoustic interlayers are often used in combination with asymmetric glass thicknesses in double glazing: one pane addresses mass and stiffness, while the laminated acoustic pane addresses the coincidence region.
Below 200 Hz, the acoustic core has little effect on transmission loss. The low-frequency behavior of a glazing system is dominated by the glass surface density, the air or gas cavity in insulating glass units, the frame compliance, and room modal coupling. At frequencies below the first panel resonance, stiffness and boundary conditions can also reduce transmission loss relative to mass-law predictions. Sound Control Plus should therefore not be specified as a sole remedy for low-frequency noise from railway freight traffic, mechanical plant rooms, or bass-heavy entertainment venues. A separate low-frequency isolation strategy may be required, including heavier glass, wider cavities, laminated glass with dissimilar panel thicknesses, or additional secondary glazing.
The service temperature of the acoustic core affects its damping peak. Many PVB-based acoustic interlayers show peak damping near 20 °C to 30 °C under typical audible-frequency excitation. At temperatures below 10 °C, the core stiffens and shear deformation decreases, reducing the acoustic benefit. At temperatures above approximately 50 °C, the core may soften to the point where its damping contribution also declines, depending on the formulation. Published data for Sound Control Plus across the full temperature range is limited in public datasheet literature; for external glazing in extreme climates, the manufacturer should be asked for the temperature-dependent loss factor or complex shear modulus. The interlayer is not a substitute for thermal insulation, and its acoustic behavior should not be extrapolated from room-temperature data without project-specific thermal modeling.
In processing trials on twin-screw and heated-roll lamination lines, batch-to-batch variation in the acoustic core can appear as slight differences in edge-flow behavior. This is relevant when laminating glass with complex cuts, holes, or notches. The soft core can flow into machined openings if the autoclave hold time is excessive or if the pressure ramp is too fast. Operators should inspect cut-outs and edge zones after a pre-production run and compare interlayer thickness loss against the quality criteria established in EN ISO 12543-2. If edge thinning exceeds the supplier’s dimensional tolerance, the autoclave pressure ramp or maximum hold temperature should be reduced before full production. The use of edge masking, edge trim allowances, and controlled cooling rates can help maintain edge geometry. After lamination, the pane should be kept in a vertical rack under shaded conditions to avoid differential heating at the edge that could produce localized interlayer movement.
Trosifol Sound Control Plus is also processed on automotive glazing lines for side windows where high-frequency wind and tire noise reduction is desired. The curved-glass lamination process uses a sag-bending step before interlayer layup. The viscoelastic core must survive the bending and cooling cycle without creep or edge separation. Published data for this specific configuration is limited in public literature, and automotive acoustic performance is usually evaluated at the vehicle level rather than as a standalone glazing rating. When automotive side glazing is specified, the finished part must meet the impact and abrasion requirements of the applicable glazing regulation rather than relying solely on acoustic interlayer performance. The product should not be combined with incompatible edge sealants or adhesive systems that may migrate into the interlayer and alter adhesion or damping.
