Unitika Ltd.

Doryokuro Kakunenryo Kaihatsu Jigyodan

Mutsunori Yamao

Yoshiaki Echigo

Tadashi Ishikura

Keiichi Asami

Yoshiyuki Suematu

Ritsuko Shidei

Keiichiro Otomura

Yoshikazu Ogura

Shingo Sasaki

Hirotaka Amimoto

Sakae Fujisaki

Kenichi Sugawara

Tuneyuki Ohsawa

A phenolic resin molding material for molding a precursor of an amorphous carbon molded article which comprises a particulate phenolic resin having thermal plasticity coated with a low-surface tension substance containing no metallic substance; a transparent precursor of an amorphous carbon molded article which comprises a homogeneous phenolic resin homogenized by molding under a highly flowing state and has few large voids and a low metal content; a process for molding the precursor which comprises molding the phenolic resin molding material with its water content being controlled by molding, i.e., kneading followed by shaping under a highly flowing state, such as transfer molding, extrusion, injection molding or injection compression molding; and a process for producing an amorphous carbon molded article which comprises carbonizing the precursor by burning. The amorphous carbon molded article produced by the present invention is suitably used as crecibles or Raschig rings in the fields of metallurgical and chemical industries, and as plasma etchers, susceptors or substrates of electronic parts in the electronic industry field.

Precursor of amorphous carbon molded article

The present invention relates to a process for producing spherical thermosetting phenolic resin particles having a size of no larger than about 1,000 microns, and the spherical thermosetting phenolic resin particles produced by this process. In accordance with the process of the present invention, a novolak resin, and a nitrogenous basic compound, and, optionally, an aldehyde, are reacted while they are suspended in an aqueous medium in the presence of a suspension stabilizer. The thermosetting phenolic resin produced by the process of the present invention not only displays superior thermal curing characteristics during molding; the cured product fabricated by molding this resin also exhibits good physical properties such as improved mechanical strength and heat resistance. Therefore, the spherical thermosetting phenolic resin particles produced by the process of the present invention can be extensively used as molding materials, binders, adhesives, and in many other applications.

Spherical particles of thermosetting phenolic resin and process for

A process for treating a waste water containing uranium and fluorine comprises a neutralizing precipitation step wherein slaked lime is added to the waste water containing uranium and fluorine and precipitate thus formed in separated and removed, and an adsorption step wherein supernatant from the neutralizing precipitation step is contacted with a chelating resin which can selectively adsorb fluorine ions and another chelating resin which can selectively adsorb uranyl ions to thereby adsorb and remove the fluorine and uranyl ions remaining in the supernatant. Eluates of the ions adsorbed by the chelating resins and waste liquors for washing and regeneration of these resins are returned to the neutralizing precipitation step. Prior to the neutralizing precipitation step, a decarbonation step may be provided for decomposing carbonate ions, if they are contained in the waste water to be treated.

Process for treating waste water containing uranium and fluorine

A resole resin in the form of microspherical particles whose surfaces are partly or entirely covered with a coating of a substantially water-insoluble inorganic salt and which are not larger than 500 .mu.m in size, and a process for producing such resole resin. The resole resin comprises solid particles that are highly heat reactive and can be stored in a stable manner for a prolonged period. The resin particles can be used with good results in all fields of applications (e.g., moldings, laminations and binders) where conventional phenolic resins are used.

Production of microspheroidal particles of resole resins

A process for separately recovering uranium and hydrofluoric acid from a waste liquor containing uranium and fluorine comprises a neutralizing precipitation step wherein a magnesium compound is added to the waste liquor containing uranium and fluorine to form a precipitate and the thus formed precipitate is then separated; a distillation step wherein an aqueous solution of sulfuric acid is added to the precipitate separated in said neutralizing precipitation step to dissolve the precipitate and the thus formed solution is then distilled to recover hydrofluoric acid as a distillate; and a uranium recovery step wherein uranium is recovered from a residue produced by said distillation step.

Process for separately recovering uranium and hydrofluoric acid from

A process for producing microspherical cured phenolic resin particles having a particle diameter of not more than about 100 .mu.m, which comprises reacting a novolak resin, a phenol and an aldehyde in an aqueous medium in the presence of a basic catalyst and an emulsion stabilizer. Novel microspherical cured phenolic resin particles are produced by this process. The resin particles have excellent impact strength and mechanical properties, a sharp particle size distribution, and a low secondary agglomerate content, and because of these properties, are useful as an excellent modifier or filler for various plastics and rubbers.

Growing community of inventors

Kyoto, Japan

Mutsunori Yamao