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:
Nov. 18, 1997
Filed:
Mar. 20, 1995
Sumitomo Chemical Company, Limited, Osaka, JP;
Abstract
The present invention relates to a method for producing a vulcanized rubber by compounding in a kneading step at a relatively high temperature, a rubber and a flavan compound of the formula (I) ##STR1## wherein R.sup.1, R.sup.2, R.sup.4 and R.sup.5 independently of one another represent a hydrogen or an aliphatic group having 1-6 6 carbon atoms, or R.sup.1 and R.sup.2 together with the carbon atoms to which they are attached and/or R.sup.4 and R.sup.5 together with the carbon atom to which they are attached form an alicyclic ring having 4-10 carbon atoms, R.sup.3 is a hydrogen or an aliphatic group having 1-6 carbon atoms, and X and Y independently of one another are hydrogen, hydroxy or an aliphatic group having 1-8 carbon atoms; also, a rubber composition containing a flavan compound according to the above formula together with a cobalt-containing compound and a methylene donor; the vulcanized rubber produced through the method or from the rubber composition exhibits excellent rubber properties such as, for example, increased hardness and processability essentially free from fuming problems.