Patents Assigned to NGK Insulators, LTS.
  • Ceramic-made filter and process for production thereof
    Patent number: 6837911
    Abstract: A ceramic-made filter for capturing the particulates present in the exhaust gas discharged from diesel engines, wherein a ceramic particles layer made of heat-resistant ceramic particles is formed on a filter by coating, the heat-resistant ceramic particles having a BET specific surface area of 300 m2/g or less. In this ceramic-made filter, the melting of the filter caused by the ash remaining and accumulating after the particulates captured by the filter have been burnt, can be prevented easily without using a large system or the like.
    Type: Grant
    Filed: July 24, 2001
    Date of Patent: January 4, 2005
    Assignee: NGK Insulators, LTS.
    Inventors: Naomi Noda, Kanji Yamada, Yoshiyuki Kasai
  • Process for producing silicon nitride sintered material
    Patent number: 5178809
    Abstract: Powders of carbides are mixed with a silicon nitride powder and powders of rare earth element oxides to obtain a mixture. The mixture is shaped and fired in a casing in a nitrogen atmosphere of 1,700.degree.-2,100.degree. C. under the conditions specified by the following formula:(0.025x-0.05)<y.ltoreq.0.1xwherein x is a firing time (hr) and y is the weight (g) of shaped material to be filled into casing divided by the internal volume (cc) of the casing.
    Type: Grant
    Filed: June 19, 1991
    Date of Patent: January 12, 1993
    Assignee: NGK Insulators, Lts.
    Inventors: Akira Takahashi, Keiichiro Watanabe