EBECRYL® 4900

EBECRYL® 4900 is a hydroxyl functional aliphatic urethane acrylate oligomer diluted in 40% butyl acetate. Here's an overview of its key characteristics and applications as described in the provided technical datasheet:

Introduction:
EBECRYL® 4900 is described as an Sn-free hydroxyl functional aliphatic urethane acrylate oligomer suitable for applications that involve a thermal reaction (NCO/OH) followed by UV energy cure (dual cure).

Performance Data:

• Characteristics: Light color, low viscosity, tack-free after solvent evaporation.
• UV/EB Cured Formulations: Exhibit high hardness and excellent cure response.

Viscosity Reduction:
It can be thinned with standard reactive diluents or solvents, including esters, ketones, and aromatic hydrocarbons. Dual-cure systems should use PU grade solvents.

Suggested Applications:
EBECRYL® 4900 can be combined with NCO-bearing resins for UV coatings cured by the dual-cure process. It is suitable for applications such as coatings for 3D parts and thermoforming applications.

Typical Physical Properties:

• Color: Gardner max. 1.0
• Density: 1.05 g/cm³ at 20°C
• Hydroxyl value: ~28 mg KOH/g
• Resin solids: 60% by weight
• Butyl acetate content: 40% by weight
• Viscosity: ~1500 mPa.s at 25°C

Thermoformable Dual Cure Formulation:
A formulation example for a thermoformable starting point formulation of a SB UV 2K system using EBECRYL® 4900 combined with multi-functional isocyanate EBECRYL® 4950 is provided.

Precautions:
Care should be taken to avoid exposing the product to high-temperature conditions, direct sunlight, ignition sources, oxidizing agents, alkalis, or acids. It contains a flammable or combustible liquid and vapor, so consult the Safety Data Sheet (SDS) for additional storage and handling recommendations.

Overall, EBECRYL® 4900 is designed for applications requiring a combination of thermal and UV curing processes, offering characteristics such as high hardness and excellent cure response.