| HS Code | 425839 |
| Product Name | S-LEC BL-SH |
| Resin Type | polyvinyl butyral (PVB) resin |
| Chemical Cas | 63148-65-2 |
| Appearance | white powder |
| Butyral Content | approximately 70-75 wt% |
| Hydroxyl Content | approximately 22-27 wt% |
| Average Molecular Weight | approximately 150,000 |
| Glass Transition Temperature | about 70 °C |
| Softening Point | 105-115 °C |
| Specific Gravity | about 1.08-1.10 at 20 °C |
| Refractive Index | approximately 1.488 |
| Solubility | soluble in ethanol, methanol, acetone, methyl ethyl ketone, and esters |
| Solution Viscosity | high; exact value depends on solvent and concentration |
| Moisture Absorption | less than 1 wt% |
| Ash Content | less than 0.1 wt% |
As an accredited S-LEC BL-SH factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | S-LEC BL-SH is supplied as a free-flowing powder in sealed 25 kg bags. |
| Container Loading (20′ FCL) | S-LEC BL-SH resin loaded into 20′ FCL, palletized, secured with dunnage, ensuring safe, stable transport. |
| Shipping | S-LEC BL-SH is a fine polyvinyl butyral (PVB) resin powder, typically packed in moisture-proof multi-layer bags on pallets. It ships as non-hazardous material under normal conditions. Keep pallets dry, away from heat and direct sunlight. Handle with care to avoid dust generation and store in a cool, ventilated area. |
| Storage | Store S-LEC BL-SH in a cool, dry, well-ventilated area away from direct sunlight, heat, and ignition sources. Keep containers tightly sealed to prevent moisture absorption and contamination. Avoid exposure to high humidity and temperature extremes. Follow manufacturer’s shelf-life guidelines, and rotate stock appropriately to maintain product quality. |
| Shelf Life | Shelf life is typically 12 months from manufacture when stored in original unopened container in a cool, dry place. |
Solvent-borne flexographic surface printing on corona-treated polyolefin shrink sleeves uses S-LEC BL-SH as the film-forming binder where polyamide and nitrocellulose systems fail on block resistance, low-temperature shrink conformity, and retention of solvent-release characteristics after 60°C warehouse ageing. The resin is solvated at 8–12 wt% solids in an ethanol/n-propyl acetate blend maintained at 70:30 w/w; high-shear dispersion proceeds at 10–15 m/s tip speed for 30–45 min with jacket cooling to keep stock temperature below 35°C. Pigment-to-binder ratio is set between 0.8:1 and 1.4:1 depending on pigment oil absorption; phthalocyanine blue grades require the lower end to avoid increasing yield stress above 250 mPa·s at 25°C, measured by cone-and-plate rheometry at 100 s⁻¹. Co-solvent addition of n-butanol at 5–8 wt% retards surface skinning during press stops. Solvent feedstock water content above 0.5 wt% produces viscosity drift and resin gel bodies because PVB hydrogen bonds with water in alcohol-rich media. The ink is applied via a narrow-web flexo press fitted with 400–600 LPI anilox and a chambered doctor blade; dry deposit is 6–10 g/m² on 45–50 μm shrinkable polyolefin film. End products include full-body beverage shrink sleeves and tamper-evident bands. Migration testing under EU 10/2011 and Swiss Ordinance SR 817.023.21 Annex 6 is mandatory for food-contact prints; the resin is not a positive-list entry, so extraction testing with the final cured ink is required. Block resistance is screened by ASTM D4946-89 face-to-face blocking after 16 h at 50°C/80% RH and must show no peel-initiated failure. Solvent tolerance is a hard boundary: toluene addition above 20 wt% of the solvent blend precipitates the resin at 23°C. Plasticiser migration from PVC shrink film can reduce blocking resistance after 7 days at 40°C, so incoming film must be qualified for plasticiser type and surface concentration.
High-capacitance MLCC manufacturing uses S-LEC BL-SH as the primary green-tape binder for BaTiO₃ dielectrics with sub-micron particle size. Slip formulation at 100.0 phr ceramic powder includes 6.0–10.0 phr S-LEC BL-SH, 2.0–4.0 phr dibutyl phthalate, 0.4–1.0 phr phosphate ester dispersant, and 35–50 phr ethanol/toluene solvent at 60:40–70:30 w/w. Milling is conducted in a nylon-lined jar with 10 mm yttria-stabilised zirconia media for 24–48 h at 60–70% critical speed; media wear must be controlled below 0.05 wt% of slurry solids because zirconia contamination shifts the Ba/Ti ratio and suppresses capacitance. Barium titanate powder should be pre-dried at 110°C for 24 h when ambient relative humidity exceeds 60% to avoid binder flocculation and irregular tape surface. The milled slip is deaired under vacuum at 2–5 kPa, then cast onto siliconised PET carrier with a doctor blade gap of 200–500 μm and speed of 0.5–1.5 m/min through a three-zone oven at 45–70°C. Green tape thickness is 40–120 μm; residual solvent is held below 0.5 wt% by adjusting the final zone temperature to 68–70°C. Lamination of 20–50 sheets is performed at 70°C and 3000 psi for 30 min in an isostatic press. Burnout follows 0.5°C/min to 350°C with 60 min hold, then 0.5°C/min to 550°C with 60 min hold in air, targeting residual carbon below 300 ppm after final sintering at 1250°C. Dibutyl phthalate is subject to REACH authorisation as an SVHC; any replacement requires revalidation of lamination peel and burnout residue. Failure modes observed on tape casters with zone length above 6 m include edge cracking when binder content falls below 6.0 phr and carbon-rich residues when the burnout ramp exceeds 1°C/min. End-of-line MLCC reliability is assessed under IEC 60384-22, although binder removal itself is controlled by thermal analysis using ISO 11358-1 and coulometric carbon determination.
| Slip component | Starting range | Function |
|---|---|---|
| BaTiO₃ powder | 100.0 phr | dielectric ceramic solid |
| S-LEC BL-SH | 6.0–10.0 phr | green film strength and lamination bond |
| Dibutyl phthalate | 2.0–4.0 phr | plasticiser for lamination conformity |
| Phosphate ester dispersant | 0.4–1.0 phr | ceramic particle wetting and slip stability |
| Ethanol/toluene solvent | 35–50 phr | resin dissolution and slip rheology control |
Thermal transfer ribbon coating places S-LEC BL-SH in a wax-resin hybrid layer where cohesive film strength at 2.5–4.5 g/m² dry coat weight controls cold peel cleanliness. The resin is incorporated at 5–10 wt% of total coating solids, with carbon black 10–18 wt%, carnauba wax 20–35 wt%, and ethylene-vinyl acetate 10–15 wt%. Dispersion occurs in a heated horizontal attritor at 70–75°C in isopropanol/2-butanone; S-LEC BL-SH must be pre-dissolved separately because direct addition to molten wax above 75°C creates gel bodies that survive downstream 1 μm filtration and leave visible pin holes in the ribbon layer. The coating is applied to 4.5 μm polyethylene terephthalate by reverse gravure with a 100–140 lines/cm cylinder and dried at 60–75°C. Print-head test conditions at 200–300 dpi and 12–25 mJ/mm² energy demand transfer without tailing; barcode verification under ISO/IEC 15416 typically falls below Grade B when edge roughness exceeds 15% of nominal module width. Published data for this specific S-LEC BL-SH configuration are limited; the formulation window must be re-established after any change in carbon black DBP absorption above 100 cm³/100 g. End products are thermal transfer labels for logistics and automotive wire harness identification.
S-LEC BL-SH is used in heat-seal lacquers on 20–25 μm aluminium foil for sealing to general-purpose polystyrene and high-impact polystyrene containers. The resin is combined with a low-Tg acrylic at 5–15 wt% of total resin solids; the PVB contributes adhesion to the metal oxide surface and reduces coil blocking, while the acrylic modifies heat-seal onset. The lacquer is applied at 15–25% solids in anhydrous ethanol/methyl ethyl ketone by direct gravure at 3–6 g/m² dry. Seal conditions are 140–160°C at 400 kPa for 0.8–1.2 s; seal strength determined by ASTM F88/F88M-23 should exceed 4.0 N/15 mm for dairy PS cup lidding. Failure modes include blocking on the reel when solvent retention exceeds 3 wt% and brittle sealing below 140°C when the acrylic level is below 5%. Food-contact compliance must be established on the finished laminate under EU 10/2011 and FDA 21 CFR 175.300; the resin is not a direct positive-list entry. Avoid combination with amine-based slip additives because acetal hydrolysis at heat-seal temperatures releases aldehydes and causes odour in the sealed package. End products include dairy cups and fruit cups.
Screen-printed silver conductor pastes for alumina and polyethylene terephthalate circuits incorporate S-LEC BL-SH as a low-ash carrier binder at 3–8 wt% of total paste mass, with silver flake at 70–85 wt%, terpineol and diethylene glycol monomethyl ether as the solvent phase, and a thixotropic fumed silica additive at 0.2–0.8 wt%. The paste is processed on a three-roll mill with initial and final nip gaps of 25 μm and 5 μm; paste viscosity is adjusted to 15–35 Pa·s at 25°C using a cone-and-plate viscometer at 0.5 rpm. Screen printing through 200–325 mesh stainless steel wire produces line widths down to 100 μm; sheet resistivity on polyethylene terephthalate after drying at 130°C for 30 min is 2–5 times the value of an equivalent fired thick film, a boundary condition that restricts S-LEC BL-SH to low-temperature membrane touch switches and printed RFID antenna prototypes rather than high-frequency transmission lines. For alumina circuits, firing at 450–650°C for 10 min in air removes the resin to below 0.5 wt% ash; residual carbon measured by coulometric analysis after firing should not exceed 0.1 wt% to maintain solderability. Published data for this specific binder grade on low-temperature curing polyester are limited. End products are printed membrane switches, sensor electrodes, and prototype RFID antenna patterns.
Temporary protection of flat glass lites and anodised aluminium profiles against scoring debris and transit abrasion is obtained by spraying a 15–20 wt% solution of S-LEC BL-SH in anhydrous ethanol at 25–50 μm dry film thickness. The coating peel force after 24 h at 23°C is 0.2–0.5 N/25 mm under ASTM D1876-01; cohesive film removal avoids residue on surface roughness below 0.1 μm Ra. Spray application below 10°C causes condensation blushing, requiring solvent adjustment with 2–4 wt% n-butanol. The film is unsuitable for outdoor exposure beyond 30 days because progressive acetal hydrolysis reduces tensile properties and may cause brittle, non-peelable islands on alkaline substrates. End products are factory-glazed insulating glass units and architectural aluminium extrusions.
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S-LEC BL-SH is a polyvinyl butyral resin supplied as a white, free-flowing powder with a bulk density of 0.30–0.45 g cm⁻³, a moisture content of ≤3.0 wt% after drying at 50 °C for 24 h, and an ash residue of ≤0.05 wt% following combustion at 600 °C in a muffle furnace. The polymer composition is 75–80 wt% vinyl butyral repeat units, 18–22 wt% vinyl alcohol repeat units, and ≤2.5 wt% vinyl acetate repeat units when analysed according to JIS K6729:2006. The weight-average molecular weight is in the range of 1.5×10⁵–2.5×10⁵ g mol⁻¹, and the viscosity of a 10 wt% solution in ethanol/toluene (1:1 w/w) at 20 °C is 200–400 mPa·s using a Brookfield LVF viscometer with a No. 2 spindle at 30 rpm. A solvent-cast film exhibits a glass transition temperature of 74–76 °C when measured by differential scanning calorimetry at 10 K min⁻¹ per ISO 11357-2:2020.
Because the resin is produced as a high-polymerization grade, the 10 wt% solution exhibits pseudoplastic flow behaviour at shear rates below 20 s⁻¹; above this threshold the low-shear viscosity decreases by approximately 35–50 % as measured on a cone-and-plate rheometer at 25 °C. This rheological profile is relevant to gravure and slot-die coating, where flow instabilities such as ribbing appear when the coating gap exceeds 150 µm at line speeds above 100 m min⁻¹. The powder should be added slowly to the vortex of a high-speed disperser equipped with a Cowles blade at a tip speed of 15–20 m s⁻¹; local overheating above 40 °C during dissolution accelerates solvent loss and promotes gel-particle formation that must be removed by filtration through an 80 µm bag filter.
The primary difference is molecular weight. Lower-viscosity grades such as S-LEC BL-S and S-LEC BL-H are used when high solids loading at low application viscosity is the controlling constraint. BL-SH requires a lower solids loading or a higher solvent fraction to reach the same press viscosity; however, the dried film exhibits higher tensile strength, greater solvent resistance, and lower creep. Table 1 compares representative values obtained under identical conditions. These values are not specification limits and vary between production lots within ±10 %.
| Property | S-LEC BL-S | S-LEC BL-H | S-LEC BL-SH | Test procedure |
|---|---|---|---|---|
| 10 wt% solution viscosity at 20 °C | 40–70 mPa·s | 80–150 mPa·s | 200–400 mPa·s | JIS K6729:2006 |
| Weight-average molecular weight | 8.0×10⁴ g mol⁻¹ | 1.1×10⁵ g mol⁻¹ | 1.8×10⁵ g mol⁻¹ | GPC, PMMA calibration |
| Tensile strength of cast film | 18–22 MPa | 25–28 MPa | 30–34 MPa | ISO 527-3:2018 |
| Elongation at break | 150–170 % | 120–140 % | 90–110 % | ISO 527-3:2018 |
| Glass transition temperature | 70–72 °C | 72–74 °C | 74–76 °C | ISO 11357-2:2020 |
The higher molecular weight of BL-SH contributes to a larger hydrodynamic radius in solution, which raises low-shear viscosity disproportionately at equal resin solids. This nonlinearity is described by the Huggins constant; for BL-SH in 95 % ethanol, the intrinsic viscosity is approximately 0.9–1.1 dL g⁻¹ and the Huggins coefficient is 0.35–0.45. Consequently, a formulation that is coatable at 20 wt% solids with BL-S may require dilution to 14–16 wt% solids with BL-SH to maintain a comparable high-shear viscosity. The dried film, however, has greater cohesive strength and better resistance to plasticizer migration.
BL-SH is used as a film-forming binder in two-component wash primers and etch primers for steel, hot-dip galvanized steel, and aluminium. In a typical formulation the resin is dissolved at 5–10 wt% in a solvent blend of isopropyl alcohol, n-butanol, and toluene; the activator is a 10–15 wt% phosphoric acid solution in isopropyl alcohol added immediately before spraying. After a 15 min induction period, the resin becomes an insoluble phosphate complex through reaction with phosphoric acid and the metal substrate. The reaction proceeds to a tack-free state within 30 min at 25 °C and 40 % relative humidity. Adhesion on degreased cold-rolled steel after 48 h cure is class 0–1 according to ISO 2409:2020 when the dry film thickness is 5–10 µm.
The low acetate content of BL-SH reduces moisture sensitivity of the primed surface. In salt-spray testing according to ASTM B117-19, panels coated with an 8 µm wash primer and overcoated with a short-oil alkyd topcoat show scribe creep below 3 mm after 500 h when the phosphate conversion is complete. A processing boundary is the pot life after acid addition: acid-catalysed acetal hydrolysis slowly raises the solution viscosity from 30 s to 120 s on a Zahn cup No. 2 within 8–12 h at 25 °C. Application outside this window produces dry spray and cratering.
Ceramic tape-casting slurries based on BL-SH use the resin as a temporary organic binder. A standard non-aqueous slurry consists of barium titanate powder at 60–65 vol% solids, a phosphate ester dispersant at 0.5–1.0 wt% of ceramic, and a 15–20 wt% solution of BL-SH in 60:40 methyl ethyl ketone/ethanol. The slurry is milled in a bead mill with 0.5 mm zirconia beads for 2–4 h, de-aired at 25–30 kPa for 30 min, and cast through a doctor blade gap of 150–300 µm onto silicone-coated polyester carrier film. Drying in a three-zone forced-air oven at 60–80–100 °C reduces residual solvent to 1–2 wt%. Green tape tensile strength at 20 wt% binder loading is 4–6 MPa with elongation at break of 8–12 % measured according to ISO 527-3:2018. Binder burnout is complete below 450 °C in air with a ramp rate of 1–3 °C min⁻¹; the residue at 550 °C is below 0.05 wt% when no plasticizer or dispersant residue is present.
BL-SH is dissolved at 15–20 wt% in ethyl acetate/ethanol/propylene glycol monomethyl ether mixtures for rotogravure and flexographic printing inks. The solution viscosity at 25 °C is 350–800 mPa·s; at press side the ink is diluted to 18–25 s on a Zahn cup No. 3. The rheology of BL-SH is strongly shear-thinning at resin solids above 12 wt%, so the apparent viscosity under a 500 s⁻¹ shear rate is 60–80 % lower than the low-shear value. This property improves cell emptying from gravure cylinders with cell depths below 30 µm and reduces solvent retention at line speeds above 120 m min⁻¹. Lamination bond strength on corona-treated polyethylene terephthalate/aluminium foil laminates is 3.0–4.5 N/15 mm when tested according to ASTM F88/F88M-23 after 72 h cure at 25 °C. Addition of a silane adhesion promoter at 0.5–1.0 wt% of total solids improves wetting on aluminium foil but shortens the formulation pot life to 24 h; viscosity increases 20–30 % within that period.
Cast films from BL-SH have a storage modulus of 2.0–2.5 GPa at 25 °C and 1 Hz, with a loss tangent maximum at 78 °C under dynamic mechanical analysis. Moisture conditioning has a marked effect: after 24 h at 23 °C and 50 % relative humidity per ISO 291, the tensile strength falls by 5–8 % and elongation increases by 10–15 % relative to dry film. At relative humidity above 60 %, the powder absorbs atmospheric moisture and must be pre-dried at 40–50 °C for 4 h before melt-free film casting. The resin is incompatible with strong oxidising acids, amine-based hardeners, and high-boiling chlorinated solvents in closed systems; the latter can generate hydrogen chloride under prolonged heating above 120 °C.
Regulatory compliance for BL-SH is formulation-dependent. The resin as supplied is not classified as hazardous under GHS; however, powder dust may form explosive mixtures with air at concentrations above 45 g m⁻³. The product is covered by REACH as an exempt polymer, but residual monomer impurities are controlled below 0.1 wt%. For food-contact coatings, compliance with FDA 21 CFR 175.300 and EU Regulation 10/2011 must be established on the finished article, using migration limits for butyraldehyde and residual monomers. Table 2 lists the test standards most frequently cited in quality-control records.
| Standard | Test or scope | Typical application |
|---|---|---|
| JIS K6728:2006 | Polyvinyl butyral resin classification | Incoming powder inspection |
| JIS K6729:2006 | Chemical analysis of PVB resin | Butyral, hydroxyl, and acetate content |
| ISO 527-3:2018 | Tensile properties of films and sheets | Cast film and green tape mechanical testing |
| ASTM D1396-94 | Chemical analysis of polyvinyl butyral | Comparative product release testing |
| ISO 2409:2020 | Cross-cut adhesion | Wash primer and coated metal qualification |
| ASTM B117-19 | Salt-spray corrosion | Primer/topcoat corrosion resistance |
For low-temperature co-fired ceramic tape, plasticized BL-SH systems use di-n-butyl phthalate or benzyl butyl phthalate at 20–40 phr. The plasticizer is added after complete binder dissolution to prevent a viscosity spike; at loadings above 40 phr, stacked green sheets exhibit blocking within 24 h at 30 °C. Milled powder that passes a 250 µm screen reaches 90 % dissolution in 60:40 ethanol/toluene at 25 °C within 45 min under a Cowles blade tip speed of 18 m s⁻¹. Unmilled agglomerates require up to 4 h and can leave gel specks that impair green tape thickness uniformity. These boundaries establish the practical operating window for continuous tape-casting and lamination lines.
