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. 04, 1990
Filed:
Aug. 15, 1989
Gunma University, Maebashi, JP;
Abstract
A ferromagnetic organic substance having a triaryl methane structure and a free radical concentration of methine carbon positions of at least 10.sup.17 radicals/g, preferably at least 10.sup.18 radials/g, is provided by polycondensing a condensed polynuclear aromatic compound or an electron donating group substituted monocyclic aromatic compound with an aromatic aldehyde in the presence of an acid catalyst, to produce a precondensate having a softening point between 30.degree. C. and 120.degree. C. and being soluble in various organic solvents, and subjecting the resulting precondensate to a dehydrogenation treatment and a purification treatment, followed by molding. Alternatively, a preferable ferromagnetic organic substance having a triaryl methane structure is also manufactured by self-polycondensing an aromatic derivative having at least one electron donating group and at least one aldehyde group in the presence of an acid catalyst and then dehydrogenating the resulting polymer by light-irradiation and/or treatment with an oxidizing agent.