Abstract: The present invention provides a bifunctional phenylene ether oligomer compound having a thermosetting functional group at each terminal, an epoxy resin containing the above oligomer compound and a use thereof. That is, it provides a sealing epoxy resin composition for sealing an electric part, an epoxy resin composition for laminates, a laminate, a printed wiring board, a curable resin composition and a photosensitive resin composition. The resins and resin compositions of the present invention are used in electronics fields in which a low dielectric constant, a low dielectric loss tangent and high toughness are required and also used for various uses such as coating, bonding and molding.

Abstract: A bifunctional phenylene ether oligomer of the formula (1), obtained by oxidation polymerization of a bivalent phenol of the formula (2) and a monovalent phenol of the formula (3), 1

Abstract: A bifunctional phenylene ether oligomer of the formula (1), obtained by oxidation polymerization of abivalent phenol of the formula (2) and a monovalent phenol of the formula (3), H&Brketopenst;O—Y&Brketclosest;a&Parenopenst;O—X—O&Parenclosest;&Brketopenst;Y—O&Brketclosest;bH  (1) HO—X—OH  (2) Y—OH  (3) wherein —X— is represented by the formula (2′),  and Y—O— is represented by the formula (3), R2, R3, R4, R8, R9, R10 and R11 in the formula (2′) and the formula (3′) being required not to be a hydrogen atom, and its use.

Abstract: A process for producing 2,2′,3,3′,5,5′-hexamethyl-[1,1′-biphenyl]-4,4′-diol, which process comprises, while setting a pH of a reaction liquid containing an alkaline aqueous solution, a surfactant, a copper catalyst and 2,3,6-trimethylphenol during a reaction in the range of from 8 to 14 and controlling the variation range of the pH of the reaction liquid within ±1, oxidatively coupling the 2,3,6-trimethylphenol with an oxygen-containing gas, and a process for producing a bifunctional phenylene ether oligomer compound having a controlled average molecular weight, comprising carrying out oxidation polymerization under a proper oxygen concentration.

Abstract: A process for producing 2,2′,3,3′,5,5′-hexamethyl-[1,1′-biphenyl]-4,4′-diol, which process comprises,

Abstract: The present invention provides a bifunctional phenylene ether oligomer compound having a thermosetting functional group at each terminal, an epoxy resin containing the above oligomer compound and a use thereof. That is, it provides a sealing epoxy resin composition for sealing an electric part, an epoxy resin composition for laminates, a laminate, a printed wiring board, a curable resin composition and a photosensitive resin composition. The resins and resin compositions of the present invention are used in electronics fields in which a low dielectric constant, a low dielectric loss tangent and high toughness are required and also used for various uses such as coating, bonding and molding.

Abstract: A bifunctional phenylene ether oligomer of the formula (1), obtained by oxidation polymerization of abivalent phenol of the formula (2) and a monovalent phenol of the formula (3),

Abstract: A method is used when manufacturing a bismuth-substituted rare-earth iron garnet single crystal (BIG) film by the LPE method. The BIG film is grown on one side of a non-magnetic garnet substrate using a melt that contains flux components and rare-earth oxides. An amount of calcium is added to the melt such that a difference between optical absorption coefficients of the film at a wavelength of 0.78 .mu.m before and after subjecting the film to hydrogen-reduction treatment ranges from 660 to 1430 dB/cm. The film is grown on a non-magnetic garnet substrate having a thickness in the range of 400-600 .mu.m, at a crystal growth temperature of the melt to form a film-substrate structure. The film-substrate structure has a curvature ranging from +0.3 to +0.7 m.sup.-1 at room temperature. The film-substrate structure is subjected to the hydrogen reduction at a temperature ranging from 320 to 400.degree. C.

Abstract: A low magnetic saturation type bismuth-substituted rare-earth iron garnet crystal film of the invention is grown on a substrate of (111) garnet single crystal (GdCa)3(GaMgZr)5O12 by using a liquid phase epitaxial method. This single crystal has a lattice constant of 1.2497.+-.0.0002 nm and has a chemical structural formula expressed byTb.sub.3-x Bi.sub.x Fe.sub.5-y-z Ga.sub.y Al.sub.z O.sub.12wherein x has the range 1.25<.times.<1.40, y+z has the range 0.50<y+z<0.65, and z/y has the range 0.45<z/y<0.75.

Abstract: A Faraday rotator is formed of a bismuth-substituted iron garnet single crystal film on which an antireflection film is formed. The antireflection film includes first, second, and third layers. The first layer is a layer of silicon dioxide. The second layer is a layer of tantalum pentoxide. The third layer is a layer of silicon dioxide. The first, second, and third layers are formed in this order from the atmosphere side on the bismuth-substituted iron garnet single crystal film. The antireflection film may be formed on both of opposing surfaces of the single crystal film.

Abstract: A Faraday rotator is formed of a bismuth-substituted iron garnet single crystal film grown by a liquid phase epitaxial method. The single crystal film is represented by a formula: Tb.sub.3-x Bi.sub.x Fe.sub.5-y-z Ga.sub.y Al.sub.z O.sub.12 wherein x has the range 1.1.ltoreq.x.ltoreq.1.5, y+z has the range 0.65.ltoreq.y+z.ltoreq.1.2, and z has the range z.ltoreq.y. The bismuth-substituted rare earth single crystal film is subjected to a magnetization process where the single crystal film is magnetized by an external magnetic field so that the film has a square magnetic hysteresis loop. The external magnetic field has a magnetic field strength of 1,000 Oe or higher and is applied in a direction normal to a surface of the bismuth-substituted rare earth iron garnet single crystal film.