Quantum yield of conversion of the photoinitiator camphorquinone

Yin Chu Chen; Jack L. Ferracane; Scott A. Prahl

doi:10.1016/j.dental.2006.06.005

Quantum yield of conversion of the photoinitiator camphorquinone

Yin Chu Chen, Jack L. Ferracane, Scott A. Prahl

School of Dentistry

Research output: Contribution to journal › Article › peer-review

92 Scopus citations

Abstract

The primary absorber in dental resins is the photoinitiator, which starts the photo polymerization process. We studied the quantum yield of conversion of camphorquinone (CQ), a blue light photoinitiator, in dental resin composites using a LED lamp (3M FreeLight) and a Quartz Tungsten Halogen (QTH) lamp (VIP) as the light curing units at five different irradiances. The molar extinction coefficient, ε₄₆₉, of CQ was 46 ± 2 cm^-1/(mol/L) at 469 nm. The reciprocity of irradiance and exposure time holds for changes of CQ absorption coefficient, that is, irradiance × exposure time (=radiant exposure) = constant. Both LED and QTH lamps yielded the same curing threshold (the radiant exposure when CQ absorption drops to 1/e) and the same quantum yield conversion under different irradiances. In our dental resin formulation (0.7 wt.% CQ with reducing agents 0.35 wt.% dimethylaminoethyl methacrylate (DMAEMA) and 0.05 wt.% butylated hydroxytoluene (BHT)) the quantum yield was measured as 0.07 ± 0.01 CQ conversion per absorbed photon.

Original language	English (US)
Pages (from-to)	655-664
Number of pages	10
Journal	Dental Materials
Volume	23
Issue number	6
DOIs	https://doi.org/10.1016/j.dental.2006.06.005
State	Published - Jun 2007

Keywords

Curing threshold
Dynamic absorption coefficient
Light-activated polymerization
Molar extinction coefficient
Radiant exposure
Reciprocity

ASJC Scopus subject areas

General Materials Science
General Dentistry
Mechanics of Materials

Access to Document

10.1016/j.dental.2006.06.005

Cite this

@article{e2f7db0ad9364f1f82a7c2757f3a9a93,

title = "Quantum yield of conversion of the photoinitiator camphorquinone",

abstract = "The primary absorber in dental resins is the photoinitiator, which starts the photo polymerization process. We studied the quantum yield of conversion of camphorquinone (CQ), a blue light photoinitiator, in dental resin composites using a LED lamp (3M FreeLight) and a Quartz Tungsten Halogen (QTH) lamp (VIP) as the light curing units at five different irradiances. The molar extinction coefficient, ε469, of CQ was 46 ± 2 cm-1/(mol/L) at 469 nm. The reciprocity of irradiance and exposure time holds for changes of CQ absorption coefficient, that is, irradiance × exposure time (=radiant exposure) = constant. Both LED and QTH lamps yielded the same curing threshold (the radiant exposure when CQ absorption drops to 1/e) and the same quantum yield conversion under different irradiances. In our dental resin formulation (0.7 wt.% CQ with reducing agents 0.35 wt.% dimethylaminoethyl methacrylate (DMAEMA) and 0.05 wt.% butylated hydroxytoluene (BHT)) the quantum yield was measured as 0.07 ± 0.01 CQ conversion per absorbed photon.",

keywords = "Curing threshold, Dynamic absorption coefficient, Light-activated polymerization, Molar extinction coefficient, Radiant exposure, Reciprocity",

author = "Chen, {Yin Chu} and Ferracane, {Jack L.} and Prahl, {Scott A.}",

note = "Funding Information: The authors would like to thank Esstech Corp. for supplying the resins. This work was supported by grants from the National Institute of Health, Grant NIH-CI-R24-CA84587-04 and NIH-NIDCR-DE07079.",

year = "2007",

month = jun,

doi = "10.1016/j.dental.2006.06.005",

language = "English (US)",

volume = "23",

pages = "655--664",

journal = "Dental Materials",

issn = "0109-5641",

publisher = "Elsevier Science",

number = "6",

}

TY - JOUR

T1 - Quantum yield of conversion of the photoinitiator camphorquinone

AU - Chen, Yin Chu

AU - Ferracane, Jack L.

AU - Prahl, Scott A.

N1 - Funding Information: The authors would like to thank Esstech Corp. for supplying the resins. This work was supported by grants from the National Institute of Health, Grant NIH-CI-R24-CA84587-04 and NIH-NIDCR-DE07079.

PY - 2007/6

Y1 - 2007/6

N2 - The primary absorber in dental resins is the photoinitiator, which starts the photo polymerization process. We studied the quantum yield of conversion of camphorquinone (CQ), a blue light photoinitiator, in dental resin composites using a LED lamp (3M FreeLight) and a Quartz Tungsten Halogen (QTH) lamp (VIP) as the light curing units at five different irradiances. The molar extinction coefficient, ε469, of CQ was 46 ± 2 cm-1/(mol/L) at 469 nm. The reciprocity of irradiance and exposure time holds for changes of CQ absorption coefficient, that is, irradiance × exposure time (=radiant exposure) = constant. Both LED and QTH lamps yielded the same curing threshold (the radiant exposure when CQ absorption drops to 1/e) and the same quantum yield conversion under different irradiances. In our dental resin formulation (0.7 wt.% CQ with reducing agents 0.35 wt.% dimethylaminoethyl methacrylate (DMAEMA) and 0.05 wt.% butylated hydroxytoluene (BHT)) the quantum yield was measured as 0.07 ± 0.01 CQ conversion per absorbed photon.

AB - The primary absorber in dental resins is the photoinitiator, which starts the photo polymerization process. We studied the quantum yield of conversion of camphorquinone (CQ), a blue light photoinitiator, in dental resin composites using a LED lamp (3M FreeLight) and a Quartz Tungsten Halogen (QTH) lamp (VIP) as the light curing units at five different irradiances. The molar extinction coefficient, ε469, of CQ was 46 ± 2 cm-1/(mol/L) at 469 nm. The reciprocity of irradiance and exposure time holds for changes of CQ absorption coefficient, that is, irradiance × exposure time (=radiant exposure) = constant. Both LED and QTH lamps yielded the same curing threshold (the radiant exposure when CQ absorption drops to 1/e) and the same quantum yield conversion under different irradiances. In our dental resin formulation (0.7 wt.% CQ with reducing agents 0.35 wt.% dimethylaminoethyl methacrylate (DMAEMA) and 0.05 wt.% butylated hydroxytoluene (BHT)) the quantum yield was measured as 0.07 ± 0.01 CQ conversion per absorbed photon.

KW - Curing threshold

KW - Dynamic absorption coefficient

KW - Light-activated polymerization

KW - Molar extinction coefficient

KW - Radiant exposure

KW - Reciprocity

UR - http://www.scopus.com/inward/record.url?scp=34247098480&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34247098480&partnerID=8YFLogxK

U2 - 10.1016/j.dental.2006.06.005

DO - 10.1016/j.dental.2006.06.005

M3 - Article

C2 - 16859741

AN - SCOPUS:34247098480

SN - 0109-5641

VL - 23

SP - 655

EP - 664

JO - Dental Materials

JF - Dental Materials

IS - 6

ER -

Quantum yield of conversion of the photoinitiator camphorquinone

Abstract

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this