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:
Oct. 05, 1999
Filed:
Jan. 13, 1998
Shinya Kumagai, Osaka, JP;
Kazuyasu Tanaka, Osaka, JP;
Tsutsunaka Plastic Industry Co., Ltd., Osaka, JP;
Abstract
A microorganism holding carrier for a fluidized bed is provided that includes an extruded foamed article having continuous cells and independent cells. The article is composed of a polyolefin resin as a main component. The continuous cells include open-cells which are opened to at least two portions of a surface of the article and a semi-open cell which are opened to only one portion of the surface of the article. A ratio of the total volume of the continuous cells to the total volume of the extruded foamed article (a volume ratio of the continuous cells) falls within a range of from 20% to 70%. Further, a ratio of the total volume of the open-cells to the total volume of the continuous cells (a volume ratio of open-cells) is 20% or more. The article may have an apparent density of 0.90 to 1.80 g/cm.sup.3 and an apparent volume from 2.0.times.10.sup.-3 to 5.0 cm.sup.3, and be in the shape of a column, or a tube having an outer diameter of 2 to 20 mm and a thickness of 5 to 30% of the outer diameter. During foam-extruding, a cylinder temperature of 180.degree. C. to 250.degree. C. and a die temperature of 200.degree. C. to 250.degree. C. are preferred. The polyolefin resin may include additives such as an inorganic filler, a foaming agent, and a blowing assistant for controlling foaming temperature of the foaming agent.