Abstract
For precise control of the release rate for fertilizers, pharmaceuticals, etc., the release characteristics were investigated by preparing active core particles coated with multiple layers of insoluble but permeable particles dispersed inside impermeable wax. The release profiles were described by a mathematical model which was successfully verified with experimental data. The two release stages were taken into account; the initial stage corresponds to a constant concentration of the inner solution during the existence of the solid core, and the final stage to a decreasing inner concentration with the elapse of time without the core. As a result, the low release rate was attained by involving the layer of a low volume fraction of permeable particles most closely to the core or by a thicker layer. Also, the effect of the layer thickness was verified to be lower than that of the volume fraction. Thus, the present results confirmed the potentiality of the multiple layer coating to achieve the desired release rate characteristics by choosing the proper combination of the volume fraction of permeable particles, the layer thickness and the position of the layer.
| Original language | English |
|---|---|
| Pages (from-to) | 496-502 |
| Number of pages | 7 |
| Journal | Journal of Chemical Engineering of Japan |
| Volume | 37 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - Apr 2004 |
| Externally published | Yes |
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Keywords
- Controlled release
- Mass transfer coefficient
- Mathematical model
- Multiple-layer coating
- Permeable particles
ASJC Scopus subject areas
- Chemical Engineering(all)
Cite this
Multiple-layer coating of solids with impermeable film dispersing permeable particles for controlled release. / Ito, Ryusei; Golman, Boris; Shinohara, Kunio.
In: Journal of Chemical Engineering of Japan, Vol. 37, No. 4, 04.2004, p. 496-502.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Multiple-layer coating of solids with impermeable film dispersing permeable particles for controlled release
AU - Ito, Ryusei
AU - Golman, Boris
AU - Shinohara, Kunio
PY - 2004/4
Y1 - 2004/4
N2 - For precise control of the release rate for fertilizers, pharmaceuticals, etc., the release characteristics were investigated by preparing active core particles coated with multiple layers of insoluble but permeable particles dispersed inside impermeable wax. The release profiles were described by a mathematical model which was successfully verified with experimental data. The two release stages were taken into account; the initial stage corresponds to a constant concentration of the inner solution during the existence of the solid core, and the final stage to a decreasing inner concentration with the elapse of time without the core. As a result, the low release rate was attained by involving the layer of a low volume fraction of permeable particles most closely to the core or by a thicker layer. Also, the effect of the layer thickness was verified to be lower than that of the volume fraction. Thus, the present results confirmed the potentiality of the multiple layer coating to achieve the desired release rate characteristics by choosing the proper combination of the volume fraction of permeable particles, the layer thickness and the position of the layer.
AB - For precise control of the release rate for fertilizers, pharmaceuticals, etc., the release characteristics were investigated by preparing active core particles coated with multiple layers of insoluble but permeable particles dispersed inside impermeable wax. The release profiles were described by a mathematical model which was successfully verified with experimental data. The two release stages were taken into account; the initial stage corresponds to a constant concentration of the inner solution during the existence of the solid core, and the final stage to a decreasing inner concentration with the elapse of time without the core. As a result, the low release rate was attained by involving the layer of a low volume fraction of permeable particles most closely to the core or by a thicker layer. Also, the effect of the layer thickness was verified to be lower than that of the volume fraction. Thus, the present results confirmed the potentiality of the multiple layer coating to achieve the desired release rate characteristics by choosing the proper combination of the volume fraction of permeable particles, the layer thickness and the position of the layer.
KW - Controlled release
KW - Mass transfer coefficient
KW - Mathematical model
KW - Multiple-layer coating
KW - Permeable particles
UR - http://www.scopus.com/inward/record.url?scp=3042690578&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=3042690578&partnerID=8YFLogxK
U2 - 10.1252/jcej.37.496
DO - 10.1252/jcej.37.496
M3 - Article
AN - SCOPUS:3042690578
VL - 37
SP - 496
EP - 502
JO - Journal of Chemical Engineering of Japan
JF - Journal of Chemical Engineering of Japan
SN - 0021-9592
IS - 4
ER -