Saint-Gobain CHR SG13-10(R) is a glass cloth–reinforced polytetrafluoroethylene pressure-sensitive adhesive tape in which a woven glass fabric is impregnated and surface-coated with PTFE, then coated on one side with a solvent-borne acrylic adhesive system. The (R) designation identifies a release liner configuration that protects the adhesive face during slitting, roll storage, and die-cutting. Nominal total thickness is 10 mil (0.25 mm); the glass reinforcement supplies tensile and dimensional stability under wrap tension, while the PTFE top surface supplies the nonstick contact interface. The product is supplied in log rolls and slit master rolls with widths from 12 mm to 300 mm depending on downstream converting requirements.

The PTFE contact surface exhibits a dynamic coefficient of friction against polished steel in the range 0.04 to 0.10 measured in accordance with ASTM D1894. The backing withstands continuous no-load exposure at 260°C; however, the acrylic adhesive governs the practical operating ceiling. Continuous shear-loaded adhesive service is specified at no more than 135°C in dry air, with short excursions to 180°C limited to a cumulative 2 h service history. Published adhesion data for the SG13 series indicates 180° peel strength to stainless steel in the range 4.5 to 8.0 N/cm after 24 h dwell at 23°C, tested per ASTM D3330/D3330M-04 at 300 mm/min crosshead speed. These values are representative; batch-to-batch variation in adhesive coat weight is controlled within ±2 g/m², but end users should verify adhesion to specific substrates because peel response is a function of surface energy, roughness, and application pressure.

On rotary band sealers and intermittent L-bar sealing stations operating at 30 to 80 cycles/min, the PTFE surface of SG13-10(R) functions as a permanent parting layer between heated jaw faces and molten polyolefin film. Seal jaw temperatures for LLDPE and LDPE packaging films typically range from 140°C to 220°C depending on line speed, web thickness, and laminate structure; without a fluoropolymer interlayer, molten polyethylene forms tenacious smears on steel jaw surfaces within a single eight-hour shift, producing film drag marks, angular tearing at the seal edge, and unplanned downtime for mechanical scraping. The glass cloth reinforcement of SG13-10(R) resists the cyclic compression and thermal loading of jaw contact better than skived unsupported PTFE film, which is prone to cold flow and tearing at die-cut edges under repeated 0.2 to 0.6 MPa jaw closure pressure.

Application coverage and usage ratio parameters specify 100% jaw-face coverage, butt seams only, a seam offset of 1 to 2 mm from the jaw edge, and an adhesive coat weight of 45 to 55 g/m². The butt-seam rule avoids a thickness step across the seal face that would otherwise transfer a compression discontinuity into the seal. Compliance for food-contact machine components rests on PTFE testing under FDA 21 CFR 177.1550 and the acrylic adhesive under FDA 21 CFR 175.105; European migration compliance is assessed under EU Regulation 10/2011, with overall migration limits of 10 mg/dm² using simulated food contact testing according to EN 1186-1. Tape replacement intervals on continuous packaging lines are logged at 6 to 12 production shifts, shortened by visible brown edge char initiating after approximately 200 h at constant 180°C jaw temperature.

Installation on heated sealers proceeds with the jaw face cooled to 30°C or below and wiped with isopropyl alcohol; the die-cut strip is positioned and consolidated with a hand roller at 15 to 35 kPa pressure, then allowed to dwell for 24 h at 23°C before the jaw is reheated. Full bond development reaches approximately 80% of ultimate peel strength within the 24 h dwell. Downstream terminal products include heat-sealed snack food pouches, medical device Tyvek-to-film lidding stock, industrial bulk sacks, and flexible intermediate bulk container liners. The acrylic adhesive is not rated for retort or steam sterilisation at 121°C saturated steam because water penetration at the seam edges induces adhesion loss within a single retort cycle; silicone adhesive versions exist but introduce silicone transfer risk on food-contact film surfaces.

Slot Liner Applications in Fractional-Horsepower Motor Windings

The glass cloth reinforcement provides tensile stability under coil insertion forces, while the PTFE coating lowers insertion friction against enameled copper wire. Slot liners cut from SG13-10(R) are inserted into stator lamination slots of fractional-horsepower motors to separate magnet wire bundles from earthed steel laminations; the coated composite requires no supplementary insulation varnish for the slot wall when a single layer is used in 600 V-class windings, but double layers are specified for higher-potential service. Dielectric breakdown voltage of a single 10 mil specimen is typically in the range 8 to 15 kV when tested per ASTM D149 using short-time test conditions; the actual value depends on electrode geometry and ambient humidity, and published data for the SG13-10(R) configuration is limited.

Application coverage and usage ratio parameters define the slot liner length as the stator stack length plus 3 to 5 mm extension at each end to prevent corona tracking at slot exit corners; slot liner width equals the slot periphery minus 0.1 mm clearance to permit insertion without buckling. End-winding wraps use a 50% half-lap spiral; lead wire insulation uses double half-lap for abrasion resistance at exit points. Compliance designations include UL 510 recognised-component status for polymeric adhesive tapes, ASTM D1000-17 test methods for pressure-sensitive adhesive-coated tapes used for electrical insulation, and MIL-I-23594C where Defence-level procurement documentation is retained in legacy platforms.

Downstream production processes involve coil insertion machines that push pre-formed windings into the liner through the slot wedge; insertion force on automated lines ranges from 8 to 15 N per slot, and edge fraying raises insertion force beyond the upper limit causing liner buckling. After insertion, stator assemblies are varnish-impregnated with solventless epoxy or unsaturated polyester systems; trickle varnishing at wire temperatures of 140°C to 160°C for 30 min softens the acrylic adhesive and can displace unsupported slot liners, so liners are retained mechanically by the slot wedge during the bake cycle. Terminal products include brushless DC motors for HVAC damper actuators, servo motors for robotics, transformer interlayer insulation, and coil-wound solenoid armatures.

What Limits Repeated Cure Cycles on Powder Booth Hangers?

Because the PTFE surface presents a low-energy boundary layer, charged powder particles do not adhere within masked zones even after multiple passes through an electrostatic cloud. In powder coating shops, threaded holes, bearing bores, and grounding pin surfaces on aluminium or steel components are wrapped with the tape before pretreatment and coating; the masking survives acidic pickling and phosphate wash stages, but the acrylic adhesive does not tolerate alkaline degreasing baths above pH 10 for more than 30 min without edge lifting. The glass reinforcement prevents tear-through when loaded hooks transfer parts through the coating line.

Application coverage and usage ratio parameters specify 100% coverage of thread engagement zones, 50% overlap on cylindrical fixtures of 25 mm diameter or greater, and consumption of approximately 1.2 linear metres per fixture for 25 mm-diameter hanger rods. Masking compliance is governed by RoHS 2011/65/EU and REACH SVHC disclosure; peel adhesion is verified in-house using ASTM D3330/D3330M-04 with a minimum acceptance of 4.5 N/cm to 304 stainless steel; backing tensile strength is tested per ASTM D3759/D3759M-05. The downstream process applies the tape at 18°C to 25°C to dry substrates after solvent wipe with a ketone cleaner; electrostatic powder deposition is carried out at 60 to 100 kV gun potential, followed by cure in forced-air ovens at 180°C to 200°C for 10 to 20 min. The tape is removed while the part is at 60°C to 80°C because warm removal reduces adhesive residue on masked threads; after three full cure cycles at 200°C, cumulative thermal exposure approaches 6 h and the acrylic layer begins cohesive failure, leaving residue that must be removed with a solvent wipe. Terminal products include cast aluminium wheels, architectural aluminium profiles, appliance panels, and medical device enclosures.

Compliance and acceptance matrix by downstream sector.

In out-of-autoclave CFRP laminating schedules where silicone release agents are prohibited by subsequent bonding or painting requirements, the glass-reinforced PTFE backing serves as a non-transferring release layer bonded to aluminium or composite tool surfaces. Silicone release agents and silicone-coated release films deposit low-molecular-weight siloxanes on cured CFRP faying surfaces; subsequent adhesive bonding of spars, ribs, or doubler plates fails cohesively when silicon contamination is detectable by FTIR-ATR per ASTM E1252 at surface concentrations above 5 µg/cm². The PTFE surface mechanically releases epoxy matrices without transferring fluorine or siloxane residue because the release mechanism depends on low surface energy rather than a sacrificial additive.

Application coverage and usage ratio parameters specify 100% tool-face coverage with butt seams, an adhesive coat weight of 50 g/m², and tool surface preparation to Ra 0.8 to 1.6 µm with final solvent wipe using isopropyl alcohol. Full adhesion after 24 h dwell at 23°C is required before first layup. Composite tooling release performance is verified via ASTM E1252 FTIR for silicone residue and peel adhesion per ASTM D3330/D3330M-04. The downstream process applies the tape to the tool with a pressure roller at 0.35 MPa, then lays prepreg plies directly against the PTFE surface under vacuum bag; debulk cycles at −0.8 bar and cure at 120°C to 180°C depending on the matrix system are followed by demoulding at 60°C. The acrylic adhesive retains adhesion through approximately 3 autoclave cycles at 177°C before peel loss on tool steel becomes measurable; continuous cure service above 180°C is not recommended because adhesive bond degradation accelerates. Epoxy resin flash at butt seams requires mechanical scraping after each demould because the PTFE surface resists wetting but not physical entrapment at the seam line. Terminal products include CFRP body panels for low-volume automotive programmes, UAV structural skins, and prosthetic sockets.

When Bolted Flange Faces Require Crevice Corrosion Isolation in Chloride-Bearing Atmospheres

Surface preparation of raised-face carbon steel flanges follows SSPC-SP1 solvent wiping followed by SSPC-SP3 hand-tool cleaning to remove loose corrosion product. The tape is then applied to the raised face as a continuous PTFE shield that prevents direct contact between chloride-laden moisture and the machined sealing surface; crevice corrosion at gasket-to-flange interfaces is a primary failure mode in offshore topside utility piping where failed gaskets cause unscheduled blowdowns and volatile organic compound release.

Application coverage and usage ratio parameters specify tape width equal to the raised face width minus 3 mm, single-layer application with butt-joined segments, 100% raised-face coverage, and bolt torque reduction of 5% to 10% to account for PTFE creep relaxation. Flange dimensional tolerance follows ASME B16.5; bolt-up torque sequencing follows ASME PCC-1-2019; chemical immersion testing uses ASTM D543-20. The PTFE backing records weight change below 0.5% after 24 h immersion in 10% hydrochloric acid at 23°C, but the acrylic edge shows weight gain above 10% by wicking over 72 h, which defines the operational boundary.

Installation is limited to ambient surface temperatures between 10°C and 35°C and relative humidity below 85%; the tape is consolidated with a roller at 0.2 to 0.4 MPa, the gasket is positioned, and the flange is closed using a star-pattern torque sequence to the target torque value, with re-torque after 24 h. Continuous service is specified up to 135°C in dry air and 80°C in wet chloride atmospheres; the tape is not specified for continuous immersion service because edge ingress of acid solutions eventually debonds the acrylic layer. Terminal products include bolted joints on caustic tank farm piping, water treatment headers, offshore topside utility lines, and chlorine dioxide skid connections.

Operational boundaries of the acrylic adhesive layer under representative downstream process environments.

On hot nip rollers in solventless lamination lines, residual polyurethane adhesive accumulates within hours unless a fluoropolymer contact surface interrupts the bond line. In dry lamination of polyethylene terephthalate film to aluminium foil using two-component solventless polyurethane laminating adhesives, nip roller temperatures are maintained at 60°C to 80°C to promote green tack before the laminate enters the curing tunnel at 35°C to 45°C; the tape is applied to the heated roller to prevent adhesive transfer that otherwise degrades laminate surface quality and shortens roller service life.

Application coverage and usage ratio parameters specify 100% roller-face coverage by width, butt seams with a 1 mm gap, wrap tension of 2 to 5 N/cm during application, and tape replacement intervals of 3 to 4 weeks on continuous web lines. Compliance for indirect food-contact packaging machinery components rests on FDA 21 CFR 175.105 for the adhesive and FDA 21 CFR 177.1550 for the PTFE backing. Print-side process control references ISO 12647-2 for offset colour management where the tape is used on delivery rollers; laboratory evaluation uses ASTM D896-04 for solvent resistance and ASTM D3330/D3330M-04 for peel. The downstream process involves roller surface cleaning with isopropyl alcohol or acetone, followed by controlled-tension spiral application on a rotating fixture and burnishing of the seam with a fluoropolymer-faced roller to prevent adhesive pick-off from web edges. Press wash solvents containing methyl ethyl ketone and ethyl acetate dissolve the acrylic adhesive at seam edges, producing edge lift within 2 h of continuous solvent-vapour exposure; therefore, the tape is not specified for gravure cylinder wrapping where doctor-blade contact pressure exceeds 50 N/cm². Terminal products include flexographic printed labels, dry-laminated flexible packaging, and thermal lamination films for document finishing.

High-Frequency Vibration Induces Adhesive Shear Creep in Airframe Harness Wrap Installations

The acrylic adhesive layer withstands continuous service at 135°C in dry air but undergoes cohesive failure after 1,000 h at 160°C when subjected to constant shear load. In airframe electrical wiring interconnection system installations, the tape is spiral-wrapped around wire bundles passing through landing gear wells, wing leading edges, and avionics bays; the PTFE surface prevents chafing against airframe structural members, while the glass cloth resists cut-through from sheet-metal edges. Harness bundle diameters in these zones range from 5 to 25 mm, and bundle movement under high-frequency vibration imposes cyclic shear on the adhesive layer.

Application coverage and usage ratio parameters specify a single half-lap at 50% overlap for standard chafe zones and double half-lap for high-abrasion landing gear zones; tape ends are secured with tie wraps and not heat-shrunk. Compliance designations include FAR Part 25.1709 EWIS design assurance, MIL-I-23594C as the pressure-sensitive insulation tape procurement specification, SAE AS 22759 for wire compatibility, and ATA Chapter 20-53 standard wiring practices for installation inspection intervals. Adhesion to fluoropolymer-insulated wire jackets is verified with ASTM D3330/D3330M-04 after 24 h dwell.

Installation occurs in MRO harness workshops under controlled tension of 2 to 4 N; the wrap is inspected for absence of adhesive ooze, seam lift, and circumferential looseness before harness assembly. The acrylic adhesive is not resistant to Skydrol LD-4 phosphate ester hydraulic fluid; immersion or continuous splash exposure produces adhesive swelling and peel strength loss within 48 h at 23°C, so the tape is excluded from wheel-well areas with documented hydraulic leakage and from fuel-wetted zones. End products include airframe electrical harness assemblies for narrow-body aircraft overhaul, engine nacelle wire bundles, and auxiliary power unit control harnesses.