| HS Code | 344336 |
| Product Name | S-LEC Opt Light |
| Manufacturer | Sekisui Chemical Co., Ltd. |
| Material | Polyvinyl butyral (PVB) |
| Product Type | Optical interlayer film for laminated glass |
| Appearance | Transparent colorless film |
| Visible Light Transmittance | ≥90% |
| Haze | ≤0.5% |
| Uv Blocking | Blocks >99% of UV light up to 380 nm |
| Refractive Index | Approx. 1.48 |
| Thickness Range | 0.38 mm to 1.52 mm depending on grade |
| Adhesion To Glass | Strong adhesion with controllable peel strength |
| Tensile Strength | ≥20 MPa typical |
| Elongation At Break | ≥200% typical |
| Dimensional Stability | Low shrinkage during lamination |
| Storage Condition | Store in a cool, dry place; protect from moisture and direct sunlight |
As an accredited S-LEC Opt Light factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | S-LEC Opt Light is packed in 20 kg net paper bags with polyethylene inner liners. Keep the container sealed and dry. |
| Container Loading (20′ FCL) | 20′ FCL: Load S-LEC Opt Light securely in a 20-foot container, with proper dunnage, ventilation, and stability for safe transport. |
| Shipping | S-LEC Opt Light is shipped in moisture-proof, sealed packaging to prevent degradation. Transport in clean, dry, temperature-controlled containers, avoiding direct sunlight and excessive pressure. Handle gently to prevent scratches or deformation. Ensure proper labeling and compliance with applicable regulations. Safe arrival requires protection from humidity, heat, and physical impact during transit. |
| Storage | Store S-LEC Opt Light in a tightly sealed, original container in a cool, dry, well-ventilated area away from direct sunlight, heat, ignition sources, moisture, oxidizers, acids, and other incompatible substances. Avoid extreme temperature fluctuations and condensation. Keep container upright and protected from physical damage. Follow manufacturer’s label instructions and use strictly within the stated shelf-life. Keep out of reach of unauthorized personnel. |
| Shelf Life | S-LEC Opt Light should be stored in a cool, dry place; typical shelf life is 12 months from manufacture date. |
In automotive laminated glazing, S-LEC Opt Light is specified as the polymer interlayer in windshield stacks that must simultaneously meet the luminous-transmittance and UV-cut requirements of ECE R43 Annex 3 and GB 9656-2021, while the completed laminate also falls under the mechanical requirements of ISO 12543-2:2021. The interlayer is supplied as roll stock in nominal thicknesses of 0.38 mm, 0.76 mm, and 1.52 mm; for a standard windshield construction of 2.1 mm bent soda-lime glass / 0.76 mm S-LEC Opt Light / 2.1 mm bent soda-lime glass, the film accounts for 15.3% of the total build thickness and 7.2% of the total laminate mass. The downstream process begins with matched-pair sag bending of the glass, edge deletion of the printed black band, washing with demineralised water having conductivity below 20 µS/cm, and conditioning of the interlayer in a clean layup room held at 18–22°C and 25–35% RH. Film moisture content is maintained below 0.4 wt% because autoclave edge bubbling and local delamination become visible when moisture exceeds 0.5 wt% during the pressure cycle. The assembled stack is passed through a vacuum-ring or vacuum-bag de-airing station at an absolute pressure below 0.02 MPa, cold pre-pressed, and then cured in an autoclave at 130–140°C and 1.2–1.5 MPa for 60–120 min. The resulting components are OEM passenger-car windshields, rear windows, and side windows, with the same interlayer providing occupant retention and UV screening of interior polymers, fabrics, and leather.
Line-level failure modes associated with this grade are dominated by moisture uptake, roll blocking, and adhesion drift. Rolls stored above 25°C and exposed to ambient RH above 35% for extended periods exhibit blocking and telescoping during unwinding; the original aluminium-foil moisture barrier must be resealed after each cut. In a 2.6 m wide autoclave load, edge-to-centre glass temperature differentials of 8–12°C can develop, requiring dwell-time extension of 20–30 min to bring the centre of the stack to full adhesion temperature. Pummel adhesion values are held in the 3–7 range to balance impact retention and edge stability, while the use of aminosilane primers with free aminopropyl groups must be avoided because localized adhesion increases and optical haze develop before the autoclave step.
Overhead architectural glazing in atriums, skylights, and sloped façade elements uses S-LEC Opt Light to meet the post-breakage retention and UV-cut requirements of EN ISO 12543-2:2021, EN 12600:2002, EN 14449:2005, and 16 CFR 1201. A typical sloped glazing stack assembles 6 mm heat-strengthened glass / 1.52 mm S-LEC Opt Light / 6 mm heat-strengthened glass; the interlayer is 11.2% of the total thickness and 5.1% of the total mass. The downstream process involves cutting, edge profiling, heat-soaking to reduce nickel-sulfide breakage risk, screen printing for edge masking, and clean-room layup with film conditioned at 20–25°C and 25–35% RH. The stack is de-aired in a vacuum bag or roller pre-press at 0.6–0.8 MPa, then autoclaved at 130–140°C and 1.2–1.5 MPa for 90–150 min. Finished products include overhead glass, curtain-wall units, glass floors, and balustrades in commercial and institutional buildings.
PVB is selected over ionoplast in applications where UV cut and cost control are the principal design drivers, but the operational boundary is service temperature. The shear modulus of PVB drops significantly above 30°C; if the design temperature of the glazing exceeds 50°C, post-breakage load transfer may be insufficient for overhead use, and a thicker PVB interlayer or an ionoplast grade must be substituted. For jumbo-format laminates such as 3.3 m × 6 m panels, the autoclave edge-to-centre temperature lag can reach 8–12°C, so dwell time typically extends by 20–30 min to prevent low adhesion at the centre. Residual moisture above 0.5 wt% in the PVB remains the main cause of edge clouding and autoclave blistering in visible zones of skylights, making roll resealing and layup-room RH control non-negotiable.
In building-integrated photovoltaics, S-LEC Opt Light functions as the front and rear encapsulant around the cell circuit in laminated modules that must demonstrate compliance with IEC 61215-2:2021, IEC 61730-2:2016, EN 50583-1:2016, and UL 61730. A representative stack places 3.2 mm low-iron front glass / 0.76 mm S-LEC Opt Light / cell circuit / 0.76 mm S-LEC Opt Light / 3.2 mm back glass, with the two PVB layers contributing 9.2% of the total laminate mass. The downstream lamination route uses a membrane vacuum laminator at 140–150°C for 15–20 min, with vacuum drawn to 0.08–0.10 MPa before membrane pressure is applied. An edge seal of butyl or polyisobutylene is applied around the module perimeter before lamination, and the finished laminate is framed with drained glazing details. The terminal product categories are BIPV spandrel panels, photovoltaic skylights, solar canopies, and façade-embedded modules.
The principal technical risk in PVB-encapsulated BIPV is edge ingress of water vapour under damp-heat conditions. Published data for the long-term damp-heat stability of this specific interlayer configuration is limited, so module qualification must be executed on a product-by-product basis under IEC 61215-2:2021, including 85°C/85% RH damp heat, thermal cycling, and humidity-freeze sequences. An edge-seal width below 10 mm or an electrically active cell located closer than 6 mm to the laminate edge increases the probability of edge clouding and adhesion loss. If the application demands a service life beyond 25 years in an exposed roof assembly, the converter must verify adhesion after damp-heat testing and avoid silane primers that generate amine by-products at the glass interface.
Security glazing based on S-LEC Opt Light is used for forced-entry and blast-loaded windows where the laminate must be tested under EN 356:2000, EN 13541:2012, EN 1063:2000, ASTM F1233-08, and UL 972. A forced-entry laminate of 3 mm glass / 0.76 mm S-LEC Opt Light / 3 mm glass / 0.76 mm S-LEC Opt Light / 3 mm glass contains two interlayer plies with a combined interlayer mass fraction of 6.7%. The downstream process uses a multi-ply layup with staggered interlayer edges, vacuum-bag de-airing, and autoclave curing at 135°C and 1.3–1.5 MPa for 120–180 min; pummel adhesion is verified on each batch and maintained in the 3–7 range to ensure glass retention during impact. Terminal products include bank teller windows, police-vehicle glazing, hurricane-resistant windows, and forced-entry doors in high-risk buildings.
The operational boundary is defined by the test level. For blast loading above EN 13541:2012 ER1, a PVB-only laminate may not retain glass fragments; the design must add a polycarbonate backing or increase the PVB stack thickness and glass ply count. Multi-ply laminates with three glass plies and two PVB interlayers can show autoclave dwell inconsistencies when total build exceeds 10 mm, and published processing guidance for very thick PVB stacks is limited. In such cases, the converter should run a thermal profile study with embedded thermocouples and extend dwell until the centre-line temperature has been held at 135°C for at least 60 min.
| Downstream zone | Normative reference | Representative stack | PVB mass fraction |
|---|---|---|---|
| Automotive windshield | ECE R43, GB 9656-2021 | 2.1 mm glass / 0.76 mm film / 2.1 mm glass | 7.2% |
| Overhead architectural | EN ISO 12543-2:2021, EN 12600:2002 | 6 mm glass / 1.52 mm film / 6 mm glass | 5.1% |
| BIPV encapsulant | IEC 61215-2:2021, IEC 61730-2:2016 | 3.2 mm glass / 0.76 mm film / cell / 0.76 mm film / 3.2 mm glass | 9.2% |
| Security glazing | EN 356:2000, EN 13541:2012 | 3 mm glass / 0.76 mm film / 3 mm glass / 0.76 mm film / 3 mm glass | 6.7% |
In UV-sensitive interior display glazing, S-LEC Opt Light is assembled between two 2 mm low-iron annealed glass plies using a 0.38 mm interlayer, giving a PVB mass fraction of 3.9%. The applicable compliance framework includes EN ISO 12543-2:2021 and EN 12600:2002 for public-area impact safety, with EN 12150-1:2015 when thermally toughened glass is substituted. The laminating route is a flatbed vacuum-bag line with cold vacuum held at 0.09 MPa, followed by autoclave curing at 135°C and 1.2 MPa for 60 min; film unwind tension is kept below 50 N/m to avoid optical distortion from roll set. The finished sheet is cut into museum display-case fronts, gallery partitions, and backlit display panels where UV filtering below 380 nm is needed to protect textiles, paper, and pigmented materials.
This configuration is not suitable for overhead glazing or structural balustrading because the 0.38 mm interlayer provides limited post-breakage load transfer compared with the 1.52 mm grade used in sloped architectural glass.
Rail vehicle side windows, door vision panels, and driver-cab glazing use S-LEC Opt Light where the laminate must satisfy the fire-safety framework of EN 45545-2:2020, including smoke density testing under EN ISO 5659-2 and lateral flame spread under ISO 5658-2. A representative rail side-window stack is 4 mm toughened glass / 0.76 mm S-LEC Opt Light / 4 mm toughened glass, placing the interlayer mass fraction at 3.9%. The downstream process follows architectural lamination: edge deletion, washing, clean-room layup, vacuum-bag or roller de-airing, and autoclave curing at 130–140°C and 1.2–1.5 MPa. Rail qualification adds batch documentation of combustibility and smoke parameters, and the finished glazing is marked with the hazard-level approval. Terminal products are rail car side windows, door vision panels, and partition screens.
PVB contributes to smoke density under fire, so the final laminate must be qualified at the target hazard level of EN 45545-2:2020. If an HL3 path requires very low smoke emission, the design may need a thicker glass cover ply, an alternative interlayer, or additional fire-protection measures; published data for the smoke contribution of this specific interlayer in full rail assemblies is limited and should be verified through assembly-level testing rather than extrapolated from film-level data.
Competitive S-LEC Opt Light prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please contact us at +8615380400285 or mail to sales2@liwei-chem.com.
We will respond to you as soon as possible.
Tel: +8615380400285
Email: sales2@liwei-chem.com
Flexible payment, competitive price, premium service - Inquire now!
Laminated glass incorporating polyvinyl butyral (PVB) interlayers is specified where post-breakage glass retention, controlled energy-absorption behaviour, and measurable optical performance must operate within a single glazing build. S-LEC Opt Light is a PVB-based interlayer formulated to manage light distribution in laminated glass rather than to serve only as a transparent adhesion layer. The product is supplied in roll form and is processed on conventional PVB lamination equipment: glass washing and drying stations, a controlled-humidity lay-up area, a nip-roller or vacuum pre-press, and an autoclave. Standard PVB thicknesses of 0.38 mm, 0.76 mm, and 1.52 mm are common in interlayer specification, but the availability of specific optical-control grades and roll widths must be confirmed from the manufacturer’s technical datasheet. Product grade designations typically encode thickness and optical management class; because these codes are customer-specific, the manufacturer’s datasheet is the only valid source. Published data for this specific configuration is limited. Because the interlayer is only one component in a safety or optical assembly, final compliance is assessed on the laminated glass product, not on the film alone.
Clear PVB interlayers are formulated to produce low haze and preserve a direct, undistorted optical path through the glazing. S-LEC Opt Light differs by introducing controlled scattering centres within the PVB matrix. If the scattering domain size is close to or larger than the visible wavelength, the dominant mechanism is Mie scattering; this broadens the forward transmitted beam without the strong inverse fourth-power wavelength dependence of Rayleigh scattering. The refractive-index difference between the matrix and the scattering domains controls the angular width of the transmitted light. The visual result in edge-lit glazing is a reduction of local luminance peaks and an increase in luminance uniformity across the panel. The product differs from acoustic PVB, which raises damping loss factor through a viscoelastic core, and from solar-control PVB, which reduces total solar transmittance via near-infrared absorption or reflection. Optical management in S-LEC Opt Light does not require the glazing to be mirror-like or coloured.
Luminous transmittance of the laminated assembly should be measured according to ISO 9050:2003 or EN 410:2011. Haze is measured according to ASTM D1003-21 or ISO 14782:2021. Because small-coupon haze measurements do not capture full-panel angular distribution, a scanning-spot luminance meter or imaging photometer should be used on a full-size prototype. Bidirectional scatter distribution function measurement may be used where precise angular output is required. Published data for this specific configuration is limited, and prototype measurement is therefore the controlling qualification method.
On a production flat-laminating line, the dominant processing risk is not the autoclave temperature itself but residual moisture and trapped air at the glass-interlayer interface. PVB is hygroscopic and moisture uptake above 0.5 wt% can generate steam bubbles during autoclave heating. The de-airing step must remove air from the laminate stack before pressurisation. In nip-roller lines, roll gap, roller surface temperature, and line speed determine de-airing performance; in vacuum-bag lines, residual pressure below 20 kPa absolute is common before autoclave loading. A standard autoclave cycle for PVB-based laminates includes heating to 135°C at 1.2 MPa and holding for 30–60 min, followed by pressure-maintained cooling to below 40°C. These are typical PVB lamination parameters rather than a cure schedule specific to the optical grade. Lamination lines that run both clear PVB and optically managed PVB may need to adjust pre-press dwell times because trapped air at the edge seal can persist into the autoclave cycle and create edge bubbles that are particularly visible under LED backlight.
Lay-up rooms should be maintained at 18°C–24°C and 20%–35% relative humidity. If roll storage has exceeded 60% relative humidity, re-drying is required before lay-up. This is an operational boundary, not a cosmetic recommendation. Dust and fibre contamination on the film surface is a rejection criterion for optical glazing because scattering centres in the interlayer may not obscure localised defects once edge-lit.
The following table identifies reference methods suitable for the qualification of laminated specimens. The methods are not product-exclusive but are the minimum analytical framework for controlling optical and mechanical consistency.
| Property | Standard/method | Equipment or condition |
|---|---|---|
| Luminous transmittance | ISO 9050:2003 / EN 410:2011 | UV-Vis-NIR spectrophotometer with integrating sphere |
| Haze | ASTM D1003-21 / ISO 14782:2021 | Haze meter with CIE Illuminant C |
| Moisture content | ASTM D6869-03 | Karl Fischer coulometric titrator with oven at 180°C |
| Yellowness index | ASTM E313-20 | Spectrophotometer with D65/10° geometry |
| Tensile properties | ISO 527-3:2018 | Universal tensile tester, 50 mm/min |
The de-airing boundary interacts with optical qualification because residual air bubbles larger than the visible wavelength act as additional scattering or reflection sites. A laminated panel with acceptable haze on a small coupon may still fail full-panel inspection if de-airing was incomplete and micro-bubbles are concentrated near the edges. Production-scale verification requires a full-size sample, not only a laboratory-scaled flat coupon.
Adhesion of the interlayer to glass is conventionally assessed by pummel adhesion or compressive shear methods. In optically managed PVB, the presence of scattering centres can alter the cohesive failure mode. A low pummel value indicates insufficient adhesion and a risk of delamination after impact; an excessively high pummel value can reduce the desired post-fracture energy-absorbing behaviour. The optimum adhesion window is a function of glass thickness, glass edge finish, and service temperature. Laminators should not assume that an autoclave profile optimised for clear PVB will produce the same pummel result for S-LEC Opt Light. The first production trial on the actual line should include pummel testing on both centre and edge coupons, and boil or bake durability testing according to the relevant safety-glazing standard. If the intended market is automotive glazing, the complete laminate must be tested under ECE R43; for architectural use, the applicable standard is EN 14449:2005 or ANSI Z26.1-1996 depending on region. The interlayer is not certified as a stand-alone safety product.
Edge-sealed illuminated panels introduce a failure mode not present in open-edge glazing: plasticiser migration from the PVB interlayer into the secondary sealant. Low-resistance polyurethane or silicone sealants can extract plasticiser at the interlayer edge, producing a stiffened, hazy zone along the frame and eventual delamination. Accelerated compatibility should be tested under the high-temperature protocol of ISO 12543-4:2021, using the same sealant and edge geometry intended for production. Solvent-based ceramic frit inks that contain amine-based bridging agents or high-boiling solvent residues can create local haze rings or edge bubbles during autoclave because volatile by-products are trapped at the glass edge. Where silicone secondary sealants are used, low-volatile-content formulations are preferred, but the final combination must be confirmed by a full-size lamination trial. The use of a sealant without qualification is an operational risk, not a supported design option.
For edge-lit architectural panels and automotive interior components, the optical output is generated by LED bars placed along one or more edges. The glass panel acts as a light guide and the interlayer redirects part of the guided light out of the plane. In such a build, the distance between LED packages and the edge of the interlayer determines the input hot-spot pattern. A high LED pitch density may produce visible bright spots; the scattering layer in S-LEC Opt Light is intended to reduce this non-uniformity. Luminance uniformity should be measured with a calibrated imaging photometer and expressed as the ratio of minimum to maximum luminance over the active area. The acceptance threshold is application-specific; no single numerical threshold applies. If the specification requires a uniformity ratio above 0.7, the complete backlight assembly must be used in the measurement because the optical path includes glass thickness, LED placement, and reflector films.
Compared with clear PVB, S-LEC Opt Light trades a fraction of direct see-through transparency for controlled forward scattering. Compared with acoustic PVB, it does not necessarily improve sound transmission loss at the coincidence dip; acoustic performance should be evaluated separately according to ISO 10140-2:2021 if required. Compared with solar-control PVB, it does not use near-infrared absorbing nanoparticles to reduce total solar transmittance; therefore, solar gain calculations should not be based on low-emissivity or solar-control assumptions. The mechanical tensile behaviour of PVB interlayers is generally measured according to ISO 527-3:2018; however, tensile data at 23°C are of limited value for architectural performance because the interlayer is constrained between glass plies and operates in shear. For the full assembly, the relevant standards are those for laminated safety glass, not for the interlayer in isolation.
Storage of S-LEC Opt Light rolls should follow the same moisture-control discipline as other PVB interlayers. Sealed packaging should remain intact until the roll has reached ambient temperature; opening a cold roll in a warm, humid room causes condensation. If visible condensation is present, the roll must not be used until re-dried and inspected for film blocking. Incompatibility with low-molecular-weight amine additives and certain solvent-based edge inks can produce haze, debonding, or discolouration. When these materials are specified, a small-scale lamination trial followed by boil or bake testing is the minimum requirement. The final optical and safety performance of S-LEC Opt Light is defined only in the complete glass-laminate assembly, not in the raw film.
