Saint-Gobain CHR SG05-10(R) Premium Glass-PTFE Backing Silicone Adhesive Pressure Sensitive Tape is a composite pressure-sensitive adhesive construction in which a woven glass-fibre fabric is impregnated and coated with polytetrafluoroethylene and then combined with a silicone adhesive mass on the opposite face. The SG prefix places the product in the manufacturer’s glass-fibre/PTFE/silicone family; the 05-10 segment is associated with nominal thickness and roll-format identifiers in the CHR coding system, while the (R) suffix is a commercial configuration indicator that may distinguish liner or roll-form details and does not modify the backing or adhesive polymer type. The non-adhesive side presents a PTFE surface with low surface energy, non-stick release behaviour, and low friction, whereas the woven glass carrier limits elongation and provides dimensional stability when the tape is tensioned across a hot bar, roller, or tool face.

Representative properties are determined under ASTM D3652/D3652M for thickness, ASTM D3759/D3759M for breaking strength and elongation, ASTM D3330/D3330M for peel adhesion to stainless steel, ASTM D149 for dielectric breakdown voltage, and ASTM D257 for electrical resistance. Published manufacturer data for the SG05-10(R) configuration should be consulted for lot-specific values; the construction class is normally specified with a nominal backing thickness near 0.005 in when the 05-10 sequence is interpreted against the product code key. Total tape thickness is higher because of the adhesive coat weight and any liner. Continuous operating temperature for the silicone adhesive is generally bounded by -73 °C to 260 °C, but the practical upper limit in a given application is determined by dwell time, substrate thermal mass, and mechanical load on the adhesive bond line.

What Limits the Continuous Service Temperature of a Glass-PTFE Silicone-Adhesive Tape?

The PTFE-coated glass backing itself can tolerate excursions above 260 °C; polytetrafluoroethylene degradation accelerates above approximately 300 °C to 340 °C in air, but short-term thermal spikes in non-oxidising environments are less aggressive. The silicone pressure-sensitive adhesive is the limiting component. Silicone adhesives remain serviceable at 260 °C for extended dwell, but their peel strength declines as the adhesive approaches its thermal ceiling and the silicone polymer network undergoes oxidative crosslinking and chain scission. At sustained temperatures above 260 °C, the adhesive can embrittle, lose tack, and transfer residue to the release surface or substrate. In heat-sealing operations where jaw temperatures are controlled between 160 °C and 220 °C, the adhesive has sufficient thermal margin for repeated cycling, but direct contact with cartridge heaters or exposed heating elements above 260 °C must be avoided unless the tape is fully shielded and mechanically clamped.

Pressure-sensitive adhesion is temperature-dependent. A silicone adhesive tape that provides adequate room-temperature tack for initial positioning may exhibit reduced shear holding power as the substrate expands thermally. On aluminium platens, differential thermal expansion between the aluminium, glass fibre, and PTFE coating can impose interfacial shear stress that is not present in room-temperature tests. Users should therefore evaluate adhesion after a simulated thermal cycle using the actual substrate roughness and heating rate rather than relying solely on initial peel values reported against stainless steel panels under ASTM D3330/D3330M.

The woven glass edges are not sealed by the PTFE coating. When the tape is used in fluid-facing or immersion applications, exposed cut edges can wick hydraulic fluid, coolant, release agent, or cleaning solvent along the glass fibre bundles. This wicking can cause edge staining, delamination of the adhesive from the backing, or contamination of the adjacent process. Edge sealing with a compatible fluoroelastomer or PTFE coating, or the use of a slitting process that fuses the edge, is recommended when the tape is installed in continuous contact with liquid media.

For roll-fed packaging machines, rotary jaw heat sealers, and form-fill-seal equipment, the tape is applied to the hot sealing surface to reduce molten polyethylene or polypropylene build-up and to provide controlled release. The practical seal temperature window for low-density polyethylene is commonly 120 °C to 160 °C, and for oriented polypropylene 160 °C to 200 °C. At these temperatures the PTFE face remains below its degradation onset and the silicone adhesive remains within its continuous service range. Machine speed, jaw pressure, and film gauge shift the interfacial temperature; pyrometric or thermocouple measurement on the tape surface is required to confirm that the adhesive bond line has not exceeded the specified limit. On high-speed intermittent sealers, failure modes observed for this class include edge lift initiated at the cut ends of the tape and adhesive ooze at the tape perimeter after prolonged dwell. Both conditions are reduced by full-width installation over the jaw edge and by avoiding adhesive exposure beyond the heated zone.

If Silicone Contamination Is Prohibited, These Process Boundaries Apply

Silicone adhesives can migrate onto adjacent surfaces through direct contact, airborne transport of low-molecular-weight siloxane species during heating, or residue transferred from the liner and cut edges. Production areas dedicated to electrostatic spray painting, optical coating, semiconductor lithography, or medical bonding often operate under silicone-free restrictions because even trace siloxane contamination can produce cratering, dewetting, or adhesion failure. In such environments, SG05-10(R) should be excluded unless the tape is fully encapsulated or isolated from the critical process zone by a verified barrier. Some converters replace the silicone adhesive with an acrylic adhesive glass-PTFE tape for lower-temperature operations where silicone contamination cannot be tolerated; however, the acrylic adhesive ceiling is lower, typically near 150 °C to 180 °C, and high-temperature release performance is reduced.

Adhesion to low-energy substrates such as untreated polypropylene, PTFE, or silicone-coated release liners develops slowly. Initial tack may be insufficient for high-speed placement; dwell time, roller pressure, and substrate pre-treatment with corona, plasma, or chemical primer can be required. The silicone adhesive generally maintains adhesion after repeated heating and cooling, but it should not be used in direct contact with silicone-sensitive inks, coatings, or adhesives unless transfer testing has been completed. The manufacturer’s shelf-life guidance for silicone pressure-sensitive tapes of this class commonly indicates 18 months from date of manufacture when stored at 21 °C and 50 % RH in original packaging; procured roll stock should be confirmed against the lot certificate.

Comparative Release and Mechanical Behaviour of Glass-PTFE, Skived PTFE, and Polyimide Carriers

Selection between SG05-10(R), skived PTFE film tape, and polyimide tape is governed by mechanical demand, release quality, conformability, and edge tolerance. The glass-PTFE construction has higher tensile strength and lower elongation than skived PTFE because the woven glass fibre carries the tensile load. This is important on narrow heat-seal jaws or when the tape must be tensioned across a long tool face without stretching or necking. Skived PTFE tapes are smoother and more conformable, which can be advantageous for low-gloss release surfaces or complex radii, but they exhibit lower tear resistance and can deform under high nip pressures. Polyimide tapes provide high dielectric strength per unit thickness and excellent chemical resistance, but they are less effective as non-stick release surfaces when compared with PTFE, particularly for hot-melt and adhesive release.

In slitting and converting, SG05-10(R) requires shear-cutting or score-cutting with the glass fibre orientation considered. Crush-cut blades can fracture the glass yarns and generate conductive fibre debris that may contaminate electrical insulation or optical assembly operations. The cut edge should be inspected for loose glass filaments before installation in clean processes. The tape can be applied to formed tooling and flat platens where a rigid, low-creep release layer is required, but it is less suitable than skived PTFE where the substrate expands unevenly or where surface smoothness is the controlling variable. For composite cure tooling, the tape is used as a release surface on tool flanges, vacuum bag tacking strips, or flash-breaker lines; the silicone adhesive must be evaluated for incompatibility with the resin system because low-molecular-weight siloxane transfer can reduce bondability of subsequently painted or bonded composite surfaces.

When SG05-10(R) is substituted for an acrylic-adhesive glass-PTFE tape on a packaging line, the primary changes are a higher thermal ceiling, reduced low-temperature initial tack, and increased risk of silicone contamination in downstream printing or coating. The substitution is most appropriate where sealing temperatures exceed 150 °C or where repeated cycling at 200 °C to 260 °C causes edge lift of acrylic adhesive. On laminating lines, the tape is applied to heated nip rolls to prevent adhesive bleed from edge trim and to reduce build-up at the web edges. Roll temperature should be measured with a contacting thermocouple rather than inferred from machine setpoint, because air gaps and web speed can lower the actual tape surface temperature while localised heating at the roll ends can exceed the setpoint. The silicone adhesive bond line must be protected from direct flame, plasma impingement, and solvent spray, all of which can degrade the adhesive before the PTFE backing shows visible change.