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:
Jul. 25, 1989
Filed:
May. 16, 1988
Steven S Lalwani, Upper Montclair, NJ (US);
William G Pursell, Sr, Woodbridge, NJ (US);
Charles J Horner, Jr, South Bound Brook, NJ (US);
GAF Corporation, Wayne, NJ (US);
Abstract
A process and apparatus is provided for making a rubber-like product from rubber scrap, such as recycled tire scrap. The process includes mixing the rubber scrap with from 1 percent to 15 percent, with respect to the weight of the rubber scrap, of added sulphur, and applying a pressure thereto of about 1000 to 3000 pounds per square inch for 1 to 10 minutes at a temperature of from about 250 degrees F. to about 450 degrees F. In addition, 1 to 8 percent, with respect to the weight of the rubber scrap, of antioxidants and antiozonants are added to the mixture of rubber scrap and sulphur. The sulphur is free sulphur. Derivative sulphur compounds, or like vulcanizing agents, can be added in place of the free sulphur of about 1 to 45 percent of the weight of the rubber scrap. The rubber scrap is buffing of recycled tire rubber, or powder made from recycled tire rubber. An apparatus for carrying out the process is also provided. The apparatus includes a heavy duty mixer for making the mixture of the rubber scrap and sulphur and antioxidants and antiozonants. The apparatus also includes a compression molding and heating apparatus for applying the pressure and temperature to the mixture. The process is particularly suitable for making roofing products.