UV Additives


Type II photoinitiators require a co-initiator, usually an alcohol or amine, functional groups that can readily have hydrogens abstracted, in addition to the photoinitiator. The absorption of UV light by a Type-II photoinitiator causes an excited electron state in the photoinitiator that will abstract a hydrogen from the co-initiator, and in the process, split a bonding pair of electrons.

Sensitization is the process of energy transfer between a sensitizer and an initiator.  This is commonly used in pigmented UV curing where the UV absorption of the pigment is much stronger than that of the initiator, thus inhibiting polymerization. A sensitizer is added that absorbs UV energy at wavelengths outside those absorbed by pigments and transfers it to the initiator.

When used without other coinitiators, hexaarylbisimidazoles require a chain transfer agent or hydrogen donor to efficiently initiate polymerization. Nitrogen compounds such as N-Phenylglycine as well as thiols (2 MBO, 2 MBT) are typically used as co-initiators with the HABI molecule.

Hampford Research specializes in the manufacture of high purity photoinitiators, co-inititiators and sensitizers for all photoactive applications. For more information, or to request samples please Click Here.

HRI Prod. #NameDescriptionCAS Number
FP5059Bis Fischer Base Ketone (BFBK)Sensitizer24293-93-4
FP5170Ethyl-4-Dimethylamino Benzoate (EDMAB)Co-initiator10287-53-3
FP5360N-Phenyl GlycineCo-initiator103-01-5
FP5365N-Phenyl Glycine LTM GradeHigh purity amine based co-initiator103-01-5
FP54009-Phenyl AcridinePI, co-initator602-56-2


Hampford Research is a leading provider of custom laser dyes, near infrared absorption dyes, dye intermediates, and blends for multiple dye applications. Our unique synthesis and purification methodology assures customers of consistent quality and performance.

For more information, or to request samples please Click Here.

HRI Prod. #NameDescriptionCAS Number
FP5200JAWHolographic Dye, 480-490 nm125594-50-5
FP5432SD-184Holographic Dye, 535-545 nm154482-35-6
FP5490TMISQHolographic Dye, 630-640 nm12243-46-8
FP5194IR 775 TosylateInfrared Dye, 770-780 nm205744-92-9
FP5192IR 813 TosylateInfrared Dye, 810-820 nm134127-48-3
FP5188IR 822 TosylateInfrared Dye, 820-830 nm162411-28-1
FP5500TLA-454 (LCV)Leuco Dye, 255-265 nm4482-70-6