The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 05, 1995
Filed:
Feb. 06, 1995
Kiyoto Ando, Kitakyushu, JP;
Hiroshi Arataki, Kitakyushu, JP;
Mitsubishi Chemical Corporation, Tokyo, JP;
Abstract
A method for producing a large size crosslinked polymer bead, which comprises dispersing a monomer phase composed essentially of a monovinyl monomer and a crosslinkable monomer in an aqueous phase containing a dispersion stabilizer and subjecting the dispersion to suspension polymerization in an oil-in-water system in the presence of a polymerization initiator, wherein: 1 at least one specific gravity-controlling agent having a specific gravity of more than 1.0 selected from the group consisting of water-insoluble inert organic solvents and water-insoluble linear polymers soluble in the monomer phase, is added to the monomer phase, and 2 if necessary, at least one specific gravity-controlling agent selected from the group consisting of water-soluble inorganic salts, is added to the aqueous phase, 3 to adjust the specific gravities (at 25.degree. C.) of the monomer phase and the aqueous phase in the ranges represented by the following formula (I):