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Title: The Influence of Phosphor and Binder Chemistry on the Aging Characteristics of Remote Phosphor Products

Abstract

The influence of phosphor and binder layer chemistries on the lumen maintenance and color stability of remote phosphor disks were examined using wet high-temperature operational lifetime testing (WHTOL). As part of the experimental matrix, two different correlated color temperature (CCT) values, 2700 K and 5000 K, were studied and each had a different binder chemistry. The 2700 K samples used a urethane binder whereas the 5000 K samples used an acrylate binder. Experimental conditions were chosen to enable study of the binder and phosphor chemistries and to minimize photo-oxidation of the polycarbonate substrate. Under the more severe WHTOL conditions of 85°C and 85% relative humidity (RH), absorption in the binder layer significantly reduced luminous flux and produced a blue color shift. The milder WHTOL conditions of 75°C and 75% RH, resulted in chemical changes in the binder layer that may alter its index of refraction. As a result, lumen maintenance remained high, but a slight yellow shift was found. The aging of remote phosphor products provides insights into the impact of materials on the performance of phosphors in an LED lighting system.

Authors:
; ; ; ;
Publication Date:
Research Org.:
RTI International
Sponsoring Org.:
USDOE
OSTI Identifier:
1358541
Report Number(s):
EE0005124
DOE Contract Number:
EE0005124
Resource Type:
Other
Country of Publication:
United States
Language:
English

Citation Formats

Davis, Lynn, Yaga, Robert, Lamvik, Michael, Mills, Karmann, and Fletcher, B. The Influence of Phosphor and Binder Chemistry on the Aging Characteristics of Remote Phosphor Products. United States: N. p., 2017. Web.
Davis, Lynn, Yaga, Robert, Lamvik, Michael, Mills, Karmann, & Fletcher, B. The Influence of Phosphor and Binder Chemistry on the Aging Characteristics of Remote Phosphor Products. United States.
Davis, Lynn, Yaga, Robert, Lamvik, Michael, Mills, Karmann, and Fletcher, B. Fri . "The Influence of Phosphor and Binder Chemistry on the Aging Characteristics of Remote Phosphor Products". United States. doi:. https://www.osti.gov/servlets/purl/1358541.
@article{osti_1358541,
title = {The Influence of Phosphor and Binder Chemistry on the Aging Characteristics of Remote Phosphor Products},
author = {Davis, Lynn and Yaga, Robert and Lamvik, Michael and Mills, Karmann and Fletcher, B.},
abstractNote = {The influence of phosphor and binder layer chemistries on the lumen maintenance and color stability of remote phosphor disks were examined using wet high-temperature operational lifetime testing (WHTOL). As part of the experimental matrix, two different correlated color temperature (CCT) values, 2700 K and 5000 K, were studied and each had a different binder chemistry. The 2700 K samples used a urethane binder whereas the 5000 K samples used an acrylate binder. Experimental conditions were chosen to enable study of the binder and phosphor chemistries and to minimize photo-oxidation of the polycarbonate substrate. Under the more severe WHTOL conditions of 85°C and 85% relative humidity (RH), absorption in the binder layer significantly reduced luminous flux and produced a blue color shift. The milder WHTOL conditions of 75°C and 75% RH, resulted in chemical changes in the binder layer that may alter its index of refraction. As a result, lumen maintenance remained high, but a slight yellow shift was found. The aging of remote phosphor products provides insights into the impact of materials on the performance of phosphors in an LED lighting system.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jun 30 00:00:00 EDT 2017},
month = {Fri Jun 30 00:00:00 EDT 2017}
}
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