US Patent No. 9,354,359

PRECURSOR SOL OF ALUMINUM OXIDE AND METHOD FOR MANUFACTURING THE SAME, METHOD FOR MANUFACTURING OPTICAL MEMBER, OPTICAL MEMBER, AND OPTICAL SYSTEM


Patent No. 9,354,359
Issue Date May 31, 2016
Title Precursor Sol Of Aluminum Oxide And Method For Manufacturing The Same, Method For Manufacturing Optical Member, Optical Member, And Optical System
Inventorship Kenji Makino, Tokyo (JP)
Tomonari Nakayama, Yokohama (JP)
Keiko Abe, Kawasaki (JP)
Katsuaki Kuge, Yokohama (JP)
Hijiri Hasegawa, Kawasaki (JP)
Assignee Canon Kabushiki Kaisha, Tokyo (JP)

Claim of US Patent No. 9,354,359

1. A precursor sol of aluminum oxide including particles containing a hydrolysate or a condensate of an aluminum compound,
a solvent, and an organo aluminum compound represented by general formula (1), wherein when a pulsed-NMR T2 relaxation curve of nuclide 1H of the precursor sol of aluminum oxide includes two components with different T2 relaxation times and the component with the longer T2 relaxation time has an abundance level of CL (%) and the component with the shorter T2 relaxation time has an abundance level of CS (%), a relative proportion RCS (%) of CS determined by equation (1) is in a range of 23.5% to 50.0%, both inclusive:
where R1 and R2 denote an alkyl, perfluoroalkyl, or allyl group of one to six carbon atoms, R3 denotes a hydrogen atom, a halogen atom, or an alkyl, perfluoroalkyl, allyl, or aryl group of one to six carbon atoms, and
n denotes an integer of 1 to 3, both inclusive