Assembling disposable and external medical device components, fluid connectors, luer fittings, housings, tubing sets, wearable sensor enclosures, and diagnostic cartridges, calls for adhesives that bond dissimilar plastics fast, hold up to sterilization, and are formulated to meet biocompatibility screening. Incure’s Cyro-Weld™ line covers this work with two chemistry families: light-cure adhesives and medical-grade cyanoacrylates.
Two Chemistries for Component Bonding
Cyro-Weld™ 5000-series are UV and visible-light curable adhesives. They stay liquid until exposed to the right wavelength, then fix in seconds, which suits automated dispensing and high-volume assembly. Grades such as 5002F, 5004F, 5005F, 5013F, and 5017F carry a fluorescing tracer so coverage can be verified under inspection light. The series is formulated to meet ISO 10993-5 cytotoxicity screening, and individual grades are validated for EtO and Gamma sterilization exposure.
Cyro-Weld™ CM-series are medical-grade cyanoacrylates that cure with ambient moisture and need no light path, making them the choice for opaque assemblies and shadowed joints. The series spans a wide viscosity range, from low-viscosity wicking grades like CM-2 and CM-3 that penetrate tight press-fit joints, through general-purpose grades such as CM-50 and CM-105, to gel and toughened grades like CM-2500 and CM-4000 for gap filling and vibration resistance. CM-series grades are formulated to meet ISO 10993-5.
Matching a Grade to the Joint
- Viscosity and gap: Wicking grades for close-fit connectors and hub-to-tube joints; medium grades for general bonding; gel grades where the gap is uneven or vertical.
- Cure access: Light-cure 5000-series where a UV path exists and cycle time is tight; moisture-cure CM-series for opaque housings and blind joints.
- Substrate: Both families bond common device plastics such as polycarbonate, ABS, acrylic, and many polyolefins after appropriate surface preparation. The plastic bonder grade-selection guide covers substrate matching in detail.
- Inspection: Fluorescing grades where automated or manual coverage verification is part of the line.
Sterilization and Compliance
Cyro-Weld™ grades are formulated to meet ISO 10993-5 cytotoxicity requirements, and specific grades are validated for ethylene oxide and Gamma irradiation sterilization without loss of bond integrity. Incure supplies materials, not finished devices; the device manufacturer remains responsible for full biological evaluation and validation of the finished assembly. These adhesives are intended for external and disposable device components, not for implantation or long-term tissue contact.
For grade recommendations against your substrates and sterilization method, Email Us.
Designing the Bond
Cyanoacrylate and light-cure acrylate bonds both perform well in thin, well-fitted joints loaded in shear rather than peel or cleavage. Where two plastics with different expansion rates are joined, a coefficient of thermal expansion mismatch drives stress at the bond line during sterilization thermal excursions and shipping; a slightly flexible toughened grade absorbs that movement better than a rigid one. Clear assemblies where the bond line is visible benefit from the guidance in choosing an adhesive for transparent bonding.
Process Notes
- Surface preparation: Clean and, for low-energy plastics, plasma or primer treat. Contamination is a leading cause of weak bonds.
- Dispensing: Both families dispense through fine needles for precise placement; the 5000-series suits inline automated dosing.
- Light cure: Verify dose at the bond with a band-matched radiometer. Spot systems such as the L9000 UV LED spot lamp deliver targeted energy to a connector or hub joint.
- Moisture cure: Control humidity and allow full fixture and cure time before handling or sterilization.
Viscosity Selection in More Detail
The number in a CM-series grade tracks its approximate viscosity in centipoise, which maps directly to how the adhesive behaves in a joint:
- Wicking grades (roughly 2–20 cP): Applied to the outside of an already-assembled press fit, they draw into the gap by capillary action. Ideal for connector-to-housing and hub-to-tube joints where disassembly to apply adhesive is not practical.
- General-purpose grades (roughly 40–500 cP): Placed on one face before assembly, they stay put long enough to mate the parts without running. The workhorse range for housing seams and bracket bonding.
- Gel and toughened grades (1,000 cP and above): Bridge uneven gaps, hold on vertical surfaces, and resist peel and impact better than thin grades, at the cost of slower cure through a thick section.
For light-cure work, the 5000-series is chosen the same way, with the added constraint that a light path must reach the bond line and the exposure must deliver the grade’s specified dose.
Applications
Cyro-Weld™ grades bond fluid-path connectors and luer fittings, tubing-to-hub joints on disposable sets, housings and covers on external monitors and wearable sensors, cartridge and cassette assembly for diagnostics, and strain relief on external cable and lead assemblies.
Frequently Asked Questions
Q: When should I choose the 5000-series over the CM-series?
A: The light-cure 5000-series suits transparent assemblies with a clear light path and tight cycle time. The moisture-cure CM-series suits opaque housings and blind joints where light cannot reach the bond line.
Q: Are these adhesives suitable for implanted devices?
A: No. Cyro-Weld™ grades are intended for external and disposable device components, not implantation or long-term tissue contact. They are formulated to meet ISO 10993-5 cytotoxicity screening, and the device manufacturer remains responsible for full biological evaluation of the finished assembly.
Q: Which grades support coverage verification?
A: The fluorescing 5000-series grades, such as 5002F, 5004F, 5013F, and 5017F, carry a tracer visible under inspection light.
To select Cyro-Weld™ grades for your components, Contact Our Team.
Visit www.incurelab.com for more information.