EBECRYL® 438

EBECRYL® 438 is characterized by:

• Good pigment wetting
• Good lithography behavior
• Fast UV cure response

UV cured products containing EBECRYL® 438 are characterized by the following performance properties:

• Good adhesion to metals, plastics and paper

The actual properties of UV/EB cured products also depend on the selection of other formulation components such as reactive diluents, additives and photoinitiators.

Formulated UV curable products containing EBECRYL® 438 may be applied via lithographic, screen, gravure, direct or reverse roll, and curtain coating methods. EBECRYL® 438 is recommended for:

• Wet lithographic inks for paper, plastics, and metals
• Promoting adhesion for coatings on metal, plastics and paper
• Overprint varnishes applied by lithography
• Post-formable inks

• Graph I shows the viscosity reduction of EBECRYL® 438 with 1,6-hexanediol diacrylate (HDDA) of allnex, isobornyl acrylate (IBOA) of allnex, propoxylated glycerol triacrylate (OTA-480), trimethylolpropane triacrylate (TMPTA), and tripropylene glycol diacrylate (TPGDA) of allnex.
• Although viscosity reduction can be achieved with non- reactive solvents, reactive diluents are preferred because they are essentially 100 percent converted during UV/EB exposure to form a part of the coating or ink, thus reducing solvent emissions.
• The specific reactive diluents used will influence performance properties such as hardness and flexibility. Graph II illustrates the change in viscosity of EBECRYL® 438 with increasing temperature.

Graph I: Viscosity Reduction With Reactive Diluent

Graph II: Viscosity Vs. Temperature

• Care should be taken not to expose the product to high temperature conditions, direct sunlight, ignition sources, oxidizing agents, alkalis or acids.
• This might cause uncontrollable polymerization of the product with the generation of heat. Storage and handling should be in stainless steel, amber glass, amber polyethylene or baked phenolic lined containers.
• Procedures that remove or displace oxygen from the material should be avoided. Do not store this material under an oxygen free atmosphere.
• Dry air is recommended to displace material removed from the container. Wash thoroughly after handling. Keep container tightly closed. Use with adequate ventilation.