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:
Aug. 08, 1978
Filed:
May. 19, 1976
Heimo Brunetti, Reinach, CH;
Jean Rody, Basel, CH;
Nobuo Soma, Tokyo, JP;
Tomoyuki Kurumada, Tokyo, JP;
Ciba-Geigy Corporation, Ardsley, NY (US);
Sankyo Company, Limited, Tokyo, JP;
Abstract
Cyclic ketals of sterically hindered 4-oxopiperidines are effective light-stabilizers for organic polymers. These compounds have at least five alkyl groups in ring positions 2,3,5 and 6 and four alkyl groups in ring positions 2 and 6, preferably methyl and ethyl groups. The ring nitrogen may be unsubstituted or substituted with a monvalent substitutent. The new compounds can be synthesized by ketalization of the corresponding 4-oxopiperidines with diols, triols or tetrols. Using triols the obtained ketals possess hydroxyl groups which may be esterified or etherified in a subsequent reaction step. Ketalization with tetrols yields cyclic bis-ketals.