Otoplastics 3Dresyn OTO-Clear CV1 Bio – Rigid to Semi-Rigid Clear Lacquer

Transparent rigid to semi-rigid UV/visible curable biocompatible lacquer for surface sealing and glazing of hard otoplastics and hearing-related shells (biocompatible high purity system)

Product description

3Dresyn OTO-Clear CV1 Bio is a biocompatible transparent lacquer developed for surface sealing and glazing of hard otoplastics and hearing-related shells produced by SLA, DLP and LCD.

It delivers high optical clarity, a smooth high-gloss surface and a sealed, easy-to-clean finish, while remaining rigid to semi-rigid and tough enough to follow thin shell walls and edges without crazing.

The formulation combines a clear coating architecture with a high purity system supporting controlled biocompatible workflows, with reduced residual monomer content when properly cured and post-processed. The composition is optimized for thin, uniform film application on shell surfaces.

It is compatible with SLA, DLP and LCD systems and with light-box post-curing used in professional audiology and dental laboratories.

Application framework

Intended for professional use as a surface lacquer and glaze on properly prepared hard polymeric otoplastic substrates, such as acrylic and methacrylate shells, processed by vat photopolymerization.

Final suitability of coated parts must be validated by the user according to the specific application, substrate, processing conditions and applicable regulatory requirements.

Typical applications

• Surface sealing and glazing of hard hearing aid shells and in-ear monitor (IEM) shells
• Transparent protective lacquering of rigid otoplastic components
• Smooth, glossy finishing of custom-fit ear components
• Sealing of surface microporosity and layer interfaces to improve clarity and cleanability

Mechanical properties 

• Tensile strength: > 45 MPa (ISO 527-1 / ISO 527-2)
• Flexural strength: > 80 MPa (ISO 178)
• Young’s modulus: 2000–3000 MPa (ISO 527)
• Elongation at break: 5–15 % (ISO 527)
• Impact resistance, Notched Izod: > 25 J/m (ISO 180:2023)
• Shore hardness: D80–90 (ISO 868)

Physical properties 

• Viscosity: Low, formulated for thin uniform film by dipping or brushing <500 mPas at 23°C (ISO 3219)
• Density: 1.0–1.2 g/cm³ (ISO 1183)
• Water absorption: < 0.05 % (24 h at 23°C) (ISO 62)

Processing-related characteristics

• Film build and coating uniformity: optimized for thin, even lacquer films
• Flow and wetting behaviour: optimized for coating intricate shell surfaces

Functional performance characteristics

• High optical clarity and non-yellowing behavior
• Smooth, high-gloss sealed surface for skin-contact comfort
• Rigid to semi-rigid and tough, following thin shell walls and edges without crazing
• Strong adhesion to properly prepared hard polymeric otoplastic substrates under validated processing conditions
• Suitable for thin-walled rigid shells
• Ceramic-free clear lacquer formulated for thin film application

Printing & processing guidelines

• Application: surface lacquer and glaze applied by dipping or brushing onto properly prepared hard otoplastic substrates
• Wavelength range: 200–420 nm, compatible with 385–405 nm printers and with light-box post-curing
• Apply thin, uniform films and post-cure to a tack-free surface
• Properly clean and prepare the substrate before coating to ensure adhesion
• Follow the 3Dresyns IFU for Ultra Gloss and Transparency and the relevant exposure and post-curing documentation

Workflow recommendations

• Validate adhesion and clarity on a test shell before production
• Use validated cleaning and post-curing workflows for biocompatible applications
• For skin-contact devices, ensure complete removal of uncured material and a validated biocompatible final cleanse

Biocompatibility & quality framework

• LOwe hazard and high purity formulation supporting controlled biocompatible workflows
• Reduced residual monomer content when properly cured and post-processed
• Biocompatibility-related testing may be performed under controlled laboratory conditions
• Evaluation frameworks may include ISO 10993 methodologies, for example ISO 10993-5 (cytotoxicity) and ISO 10993-10 (irritation and skin sensitization)
• Manufacturing aligned with ISO 13485 quality management systems
• Organo-tin free formulation
• Final biological performance depends on validated processing workflow

Testing & processing disclaimer

Reported values are indicative targets pending final formulation validation and are provided for reference only. Coating properties are determined on coated and post-processed specimens and may vary depending on substrate type, surface preparation, curing conditions and workflow validation.

Regulatory & legal notice

This material is supplied as a professional manufacturing material for audiology and otoplastics workflows and is not marketed as a finished medical device. The regulatory classification, conformity assessment and validation of any final device manufactured or coated using this material remain the sole responsibility of the legal manufacturer in accordance with applicable regulations, including Regulation (EU) 2017/745.

Why choose 3Dresyn® OTO-Clear CV1 Bio

• Transparent lacquer with high optical clarity and non-yellowing behavior
• Smooth, high-gloss sealed surface for skin-contact comfort
• Rigid to semi-rigid and tough, resisting crazing on thin shell walls
• Biocompatible, ceramic-free clear lacquer optimized for thin film application
• High purity and organo-tin free formulation with reduced residual monomer after proper cure
• Compatible with SLA, DLP and LCD systems and light-box post-curing

Document reference: TDS-OTO-CLEAR-CV1-BIO-EN | Version: 1.0 | Last updated: June 2026