Toagosei Chemical Industry, Co., Ltd.

Ngk Spark Plug Company, Limited

Toagosei Company, Ltd.

Hideki Kato

Noriyuki Yamamoto

Shuichi Ohsumi

Koji Sugiura

Takuya Oomura

Hiroki Kourai

Junichiro Suzuki

Toshiro Hirose

Masaru Matsubara

Yuki Hatano

Kenichi Ishizaki

Hidemu Inoue

Satoru Maekawa

Takahisa Ogasawara, Deceased

Yasuhiro Ninomiya

Masami Asai, Deceased

Hideaki Yukimachi

Kazuhiro Shintani

Shinya Ogimoto

Makoto Nomura

Tomohisa Iinuma

Hiroshi Yoshida

Nobuhiko Aiba

A ceramic cutting tool including a ceramic base memberof a tool main bodywhich is formed of a composite ceramic which contains a hard phase dispersed within an alumina matrix phase. The hard phase contains, as a predominant component, one or more elements selected from hard-phase-forming metal elements M in the form of at least one of a carbide, nitride, or boride, or in the form of a solid solution of at least two selected from the carbide, nitride and boride. The hard-phase-forming metal elements M include Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W and Si. The surface of the ceramic base memberis covered with a coating layer, which contains titanium carbonitride or titanium nitride as a predominant component. The coating layerhas an average crystal-grain size of 0.1 to 0.5 &#x3bc;m as observed on the surface, and an average thickness of 0.5 to 2 &#x3bc;m. The coating layeris formed by a CVD at a low to medium temperature range of 750 to 900&#xb0; C. The ceramic cutting tool can be fabricated at low cost and can secure stable cutting performance over a long period even when the tool is used under severe cutting conditions under which large thermal and mechanical loads act on the tool.

Cutting tool

A cutting toolincludes a hard coating formed on the surface of a substrate formed of, for example, a hard material of cemented carbide (WC-Co-type cemented carbide) equivalent to JIS K10 and polished into the shape of ISO SPGN120312. The cutting toolhas a plate-shape with a rake face (the main surface side) that is wider than the opposite face. The hard coating has a thickness in the range of from 1 &#x3bc;m to 5 &#x3bc;m, is formed of a TiAlN material, and has a Ti/Al ratio of 1. Coarse grains present in the hard coating and having a size not less than coating thickness occupy an area percentage not greater than 5% by area. The hard coating has a surface roughness Ra of not greater than 0.1 &#x3bc;m and a surface roughness Rz of not greater than 1 &#x3bc;m.

Cutting tool and tool with holder

Cutting tools and wear-resistant materials formed of a silicon-nitride-based sintered body having excellent characteristics, such as high wear resistance. Cutting tool,is in the form of a negative chip having a shape prescribed by ISO standard: SNGN 120408. Specifically, the cutting tool,is a chip of a rectangular parallelepiped shape which has a thickness of 4.76 mm and in which each of four sides (cutting edges),on a rake face,side has a length of 12.7 mm. In the region having a width of 0.2 mm or less and extending from the cutting edges,of the cutting tool,, the cutting tool,has a microhardness H. Plast of 21.2 GPa or greater and a microhardness HU of 11.2 GPa or greater. The Vickers hardness of the cutting tool,as measured at a substantial center of the rake face,is 14.5 GPa or greater. Further, the amount of oxygen within the cutting tool,is 1.0 to 2.0 wt. %. Also disclosed is a method of quality control of an article having a surface, at least a portion of which is curved, which includes measuring one or both of microhardness H. Plast and microhardness HU in the vicinity of the curved portion of the surface, and either accepting or rejecting the article based on the measurement values.

Cutting tool and wear resistant material

Ceramic cutting tool

Titanium carbo-nitride complex silicon nitride tool is composed mainly of titanium carbo-nitride and silicon nitride and contains 10 to 56 wt % of Ti, 11.6 to 51 wt % of Si and 1 to 21 wt % in total of one or two or more of Ce, Y, Yb and Dy. The tool is mainly composed of Si.sub.3 N.sub.4 superior in both strength and resistance against thermal shock and TiCN superior in the effect of suppressing reactivity of Si.sub.3 N.sub.4 with Fe and exhibiting high hardness. By using oxides CeO.sub.2, Y.sub.2 O.sub.3, Yb.sub.2 O.sub.3 and Dy.sub.2 O.sub.3 as sintering aid so that the sum of the amounts of Ce, Y, Yb and Dy will be in the above range, both the resistance against flank notch (wear) of the end edge and resistance against thermal shock are improved resulting in improved durability as compared to the conventional silicon nitride cutting tool.

Titanium carbo-nitride complex silicon nitride tool

An antimicrobial composition, characterized by containing an inorganic compound on which silver ion is supported and a compound represented by the following formula �2!: ##STR1## wherein R.sup.1 is hydrogen or a lower alkyl group and R.sup.2 is hydrogen or an alkali metal.

Antimicrobial composition

Si.sub.3 N.sub.4 based ceramics are prepared by molding, calcining and sintering a powder mixture of columnar-shaped Si.sub.3 N.sub.4 particles having a particular size, a minor quantity of sintering aids and equiaxed Si.sub.3 N.sub.4 particles. The ceramics have a structure containing a specific quantity of coarse columnar grains grown from the coarse columnar-shaped particles as seed crystals, and superior in wear resistance, resistance to chipping and thermal resistance, and useful as wear resistant components or cutting tools. The ceramics can be produced without recourse to hot press sintering by normal sintering or sintering under a gas pressure, or further by applying HIP.

Method for preparing silicon nitride based ceramics

A process for producing an antimicrobial compound represented by the following formula [1]:

Process for producing antimicrobial compounds

A process for producing an antimicrobial fiber having a silver-containing inorganic microbicide characterized by using a treating solution for producing said fiber which contains a discoloration inhibitor represented by the following general formula: ##STR1## wherein R.sup.1 is hydrogen or a lower alkyl group and R.sup.2 is hydrogen or an alkali metal.

Process for producing antimicrobial fiber

The present invention provides a microbicide which comprises a phosphate represented by the following general formula:

Microbicides

Disclosed is a granular inorganic ion exchanger which is obtained by firing at 400.degree. C. or higher a granular molded product of a mixture of a metal alkoxide such as Si(OMe).sub.4 or hydrolyzate thereof, a clay mineral such as sepiolite and an inorganic ion exchanger such as antimony pentoxide and which has mechanical strength and heat resistance without losing its inherent ion exchangeability.

Granular inorganic exchangers

An epoxy resin composition for use in sealing semiconductors, having enhanced moisture resistance reliability is disclosed, which comprises an epoxy resin and an oxyacid bismuth oxyhydroxide represented by the following formula (1):

Epoxy resin composition for use in sealing semiconductors

A method for preventing aluminum corrosion in electronic parts which comprises adding lead hydroxy apatite and/or cadmium hydroxy apatite to constituents of the electronic parts through which halogen ions pass, so that said ions may be captured by said apatites in said constituents.

Method for preventing aluminum corrosion in electronic parts

This invention provides an insulating protective material effective for protection of electronic and electric devices such as electronics elements. This insulating protective material contains at least one hydrous oxide of a metal which has ion exchange properties together with a fusion bonding component such as low-melting glass, epoxy resin, phenolic resin, silicone resin, etc. and a filler such as fused silica, .beta.-eucryptite, glass fiber, glass beads, etc. Said specific hydrous oxide can be used together with a sulfur-containing organic high molecular weight compound. The hydrous oxides used in protective materials as a sealing material for electronic and electric devices can capture an ionic impurity eluted from the components of the protective material and fix it therein thereby to provide stable electronic materials excellent in performance.

Growing community of inventors

Aichi, Japan

Hideki Kato