Liquid purification or separation – Processes – Chromatography
Reexamination Certificate
2006-04-25
2006-04-25
Therkorn, Ernest G. (Department: 1723)
Liquid purification or separation
Processes
Chromatography
C210S635000, C210S198200, C210S502100
Reexamination Certificate
active
07033505
ABSTRACT:
The present invention provides packings for high performance liquid chromatography whose residual silanol groups are extremely reduced and which remarkably prevent tailing of basic compounds. Endcapping agents represented by the following general formula [II] are reacted in liquid phases or gas phases with silica gel which is surface-modified with chemical modifying agents to link the endcapping agents to the residual silanol groups on the silica gel surface. In the formula, R3and R4, the same or different, are alkyl having one to four carbon atoms, and n is the factor of structural unit and an integer of 2 to 10.
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EPO Search Report mailed on Aug. 30, 2004.
Yoshihisa Sudo, “End-capping of octadecylsilylated silica gels by high-temperature silylation”, Journal of Chromatography A. Elsevier Science, NL, vol. 737, No. 2, Jun. 21, 1996, pp. 139-147, XP004038984, ISSN: 0021-9673.
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Daiso Co., Ltd
Therkorn Ernest G.
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