Abstract: The present invention provides a method for producing a liquid-crystalline polyester resin composition, the method comprising providing a twin-screw extrusion granulator that comprises a cylinder provided with at least one supply port and two screws installed in the cylinder; supplying (A) a liquid-crystalline polyester and (B) a titanium oxide filler into the cylinder through one of the at least one supply port; and melt-kneading the components (A) and (B), wherein a cylinder setting temperature is set at a temperature of (Tm?10)° C. or lower wherein Tm is a fluidization temperature of the component (A).

Abstract: To provide a liquid crystal polyester composition which is suited for use as a material for forming a liquid crystal polyester film having excellent thermal conductivity. Also, an excellent electronic circuit board is provided by using an insulating film obtained from the liquid crystal polyester composition. The liquid crystal polyester composition of the present invention is composed of a liquid crystal polyester, a solvent and a thermally conductive filler. The thermally conductive filler is contained in the amount of 50 to 90 volume % based on the total amount of the liquid crystal polyester and the thermally conductive filler, and the thermally conductive filler contains 0 to 20 volume % of a first thermally conductive filler having a volume average particle diameter of 0.1 ?m or more and less than 1.0 ?m, 5 to 40 volume % of a second thermally conductive filler having a volume average particle diameter of 1.0 ?m or more and less than 5.

Abstract: The present invention provides a process for producing a liquid crystal polyester-impregnated base material, comprising steps of (1) impregnating a fiber sheet with a liquid composition containing a liquid crystal polyester and an organic solvent dissolving the liquid crystal polyester, (2) removing the organic solvent from the impregnated liquid composition, thereby forming an intermediate, and (3) heat treating the intermediate at 270° C. or higher and a lower temperature than a pyrolysis temperature of the liquid crystal polyester.

Abstract: The present invention provides a resin composition comprising the component (A) liquid-crystalline polyester, and the component (B) a titanium oxide filler having a volume average particle diameter of 0.27 to 0.4 ?m, wherein the component (B) is contained in an amount of from 5 to 110 parts by mass relative to 100 parts by mass of the component (A); a reflective plate of the resin composition, and a light-emitting device having the reflective plate. According to the resin composition of the present invention, it is possible to obtain a reflective plate exhibiting high reflectance of a visible light while keeping excellent mechanical strength of the liquid-crystalline polyester. Also, a light-emitting device excellent in characteristics such as brightness can be obtained using the reflective plate.

Abstract: To provide a liquid crystal polyester composition which is suited for use as a material for forming a liquid crystal polyester film having excellent thermal conductivity. Also, an excellent electronic circuit board is provided by using an insulating film obtained from the liquid crystal polyester composition. The liquid crystal polyester composition of the present invention is composed of a liquid crystal polyester, a solvent and a thermally conductive filler. The thermally conductive filler is contained in the amount of 50 to 90 volume % based on the total amount of the liquid crystal polyester and the thermally conductive filler, and the thermally conductive filler contains 0 to 20 volume % of a first thermally conductive filler having a volume average particle diameter of 0.1 ?m or more and less than 1.0 ?m, 5 to 40 volume % of a second thermally conductive filler having a volume average particle diameter of 1.0 ?m or more and less than 5.

Abstract: The present invention provides a liquid crystalline polyester resin composition suitable for an optical pickup unit. The composition comprises a liquid crystalline polyester, a mica and a hollow filler. Using the liquid crystalline polyester resin composition, an optical pickup unit with a high soldering resistance and a high torsional elastic modulus can be produced while suppressing breakage of the hollow filler in the composition.

Abstract: The present invention provides a resin composition comprising the component (A) liquid-crystalline polyester, and the component (B) a titanium oxide filler having a volume average particle diameter of 0.27 to 0.4 ?m, wherein the component (B) is contained in an amount of from 5 to 110 parts by mass relative to 100 parts by mass of the component (A); a reflective plate of the resin composition, and a light-emitting device having the reflective plate. According to the resin composition of the present invention, it is possible to obtain a reflective plate exhibiting high reflectance of a visible light while keeping excellent mechanical strength of the liquid-crystalline polyester. Also, a light-emitting device excellent in characteristics such as brightness can be obtained using the reflective plate.

Abstract: The present invention provides a liquid crystalline polyester resin composition suitable for an optical pickup unit. The composition comprises a liquid crystalline polyester, a mica and a hollow filler. Using the liquid crystalline polyester resin composition, an optical pickup unit with a high soldering resistance and a high torsional elastic modulus can be produced while suppressing breakage of the hollow filler in the composition.

Abstract: The present invention provides a method for producing a liquid-crystalline polyester resin composition, the method comprising providing a twin-screw extrusion granulator that comprises a cylinder provided with at least one supply port and two screws installed in the cylinder; supplying (A) a liquid-crystalline polyester and (B) a titanium oxide filler into the cylinder through one of the at least one supply port; and melt-kneading the components (A) and (B), wherein a cylinder setting temperature is set at a temperature of (Tm?10)° C. or lower wherein Tm is a fluidization temperature of the component (A).

Abstract: The present inventions provides a liquid-crystalline polyester resin mixture comprising a liquid-crystalline polyester, a particulate titanium oxide and at least one compound selected from the group consisting of a fatty acid amide and a fatty acid metal salt, wherein the resin mixture contains the particulate titanium oxide in an amount of 40 to 80 parts by weight and the at least one compound in an amount of 0.005 to parts by weight, both the amounts being based on 100 parts by weight of the component (A) in the resin mixture.

Abstract: The present invention provides a reflection plate made of a resin composition comprising a liquid crystalline polyester, a titanium oxide filler and a silica-based filler containing 85% by weight or more of silicon oxide, wherein the resin composition contains the titanium oxide filler in the amount of from 5 to 80 parts by weight and the silica-based filler in the amount of from 0.01 to 20 parts by weight on the basis of 100 parts by weight of the liquid crystalline polyester. The reflection plate has an excellent reflectance, especially to light in a visible range, while maintaining excellent heat resistance of the liquid crystalline polyester.

Abstract: The present invention provides a thermosetting polyether resin obtained by polycondensing a dihalogen compound with a bisphenol compound to obtain a polyether resin having a repeating unit represented by the formula (1), and introducing a functional group which causes a cross-linking reaction by heating into the resulted polyether resin; The present invention also provides a polyether resin having a low dielectric constant represented by the formula (3):