Polymer-related chemicals

Photo base generators (WPBG series)

A Photo base generator is a compound which generates organic base such as amines upon irradiation of light in the UV range. The generated organic base accelerates an anionic UV curing of epoxy resin, sol-gel method, etc.

Diagram showing base generation by irradiating a base generator with UV light

Characteristics of anionic polymerization

  • Can be used in air. (No disturbance of curing)
  • Can conduct delay cure. (Anion of active species is not deactivated)
  • Can be used on metal wiring. (Hardly causes metallic corrosion)
Active Species Example of Reaction Inhibition Delay cure Metallic Corrosion
Radical Example of radical polymerization reaction O2 Non Non
Cationic Example of cationic polymerization reaction H2O Yes Yes
Anionic Example of anionic polymerization reaction Non Yes Non

Different reactions utilizing bases

Organic bases are able to initiate different curing reactions by utilizing their nucleophilicity and basicity. Bases are also available for purposes other than curing agents. For example, as a catalyst for depolymerization and neutralizer for acidic systems.

Six examples of reactions using organic bases

WPBG-300

CAS RN® : 1801263-71-7

  • Can be employed with cross-linking agents such as thiol or anhydride.
  • Generates a strong base biguanide (pKbH=31.8) and radical upon irradiation.
  • Can be exposed with sensitizer at 365 nm and longer wavelength.
Structural formula of WPBG-300 View

WPBG-345

CAS RN® : 2073916-67-1

  • Shows high stability (pot life) in various compositions.
  • Generates a strong base biguanide (pKbH=31.8) and radical upon irradiation.
  • Can be exposed with sensitizer at 365 nm and longer wavelength.
Structural formula of WPBG-345 View

WPBG-266

CAS RN® : 1632211-89-2

  • Is optimal as catalyst for sol-gel method
  • Generates a strong base biguanide (pKbH=31.8) and radical in high quantum yield upon irradiation.
  • Shows high solubility to various solvents
  • Was co-developed with Dr. Koji Arimitsu, Professor, Tokyo University of Science.
Structural formula of WPBG-266 View

WPBG-018

CAS RN® : 1228312-05-7

  • Light absorption in long-wavelength region, and has excellent solubility.
  • Generates a weak base diethylamine upon irradiation.
Structural formula of WPBG-018 View