Abstract: It is an object of the present invention to provide a clathrate that suppresses a curing reaction at low temperature to promote an improvement in storage stability (one-component stability), and can effectively cure a resin by heating treatment. A clathrate suitable for the clathrate is a clathrate containing (b1) at least one selected from the group consisting of an aliphatic polyvalent carboxylic acid, 5-nitroisophthalic acid, 5-tert-butylisophthalic acid, 5-hydroxyisophthalic acid, isophthalic acid, and benzophenone-4,4?-dicarboxylic acid; and (b2) at least one selected from the group consisting of an imidazole compound represented by the following formula (I), and 1,8-diazabicyclo[5.4.0]undecene-7, at a molar ratio of 1:1.

Abstract: A curing catalyst (clathrate compound) for which the curing reaction is suppressed at low temperatures, allowing an improvement in the one-pot stability, but which can effectively cure a resin upon heat treatment. The clathrate compound includes at least an isophthalic acid compound represented by Formula (I), where R1 represents a C1 to C6 alkyl group, a C1 to C6 alkoxy group, a nitro group, or a hydroxyl group, and an imidazole compound represented by a Formula (II) where R2 represents a hydrogen atom, a C1 to C10 alkyl group, a phenyl group, a benzyl group, or a cyanoethyl group, and R3 to R5 each independently represents a hydrogen atom, a nitro group, or a halogen atom, or a C1 to C20 alkyl group, phenyl group, benzyl group, or C1 to C20 acyl group that may have a substituent.

Abstract: The invention is an epoxy resin composition for sealing a semiconductor, including (A) an epoxy resin and (B) a clathrate complex. The clathrate complex is one of (b1) an aromatic carboxylic acid compound, and (b2) at least one imidazole compound represented by formula (II): wherein R2 represents a hydrogen atom, C1-C10 alkyl group, phenyl group, benzyl group or cyanoethyl group, and R3 to R5 represent a hydrogen atom, nitro group, halogen atom, C1-C20 alkyl group, phenyl group, benzyl group, hydroxymethyl group or C1-C20 acyl group. The composition has improved storage stability, retains flowability when sealing, and achieves an effective curing rate applicable for sealing delicate semiconductors.

Abstract: A solid semiconductor sealing composition that includes (A) an epoxy resin, and (B) a clathrate complex. The clathrate complex contains (b1) at least one of 5-hydroxyisophthalic acid and 5-nitroisophthalic acid; and (b2) at least one of 2-ethyl-4-methylimidazole and 2-phenyl-4-methyl-5-hydroxymethylimidazole. A method of sealing a solid semiconductor using the sealing composition.

Abstract: The present invention provides a liquid curable epoxy resin composition that has excellent storage stability and curing properties and provides a cured product having excellent properties, particularly, excellent organic solvent resistance. For that purpose, a clathrate containing a carboxylic acid compound and at least one selected from the group consisting of an imidazole compound represented by formula (I), wherein R1 to R4 each represent a hydrogen atom or the like, and 1,8-diazabicyclo[5.4.0]undecene-7 (DBU) is mixed in an epoxy resin. The liquid curable epoxy resin composition uses a liquid epoxy resin or an organic solvent.

Abstract: A curing catalyst (clathrate compound) for which the curing reaction is suppressed at low temperatures, allowing an improvement in the one-pot stability, but which can effectively cure a resin upon heat treatment. The clathrate compound includes at least an isophthalic acid compound represented by Formula (I), where R1 represents a C1 to C6 alkyl group, a C1 to C6 alkoxy group, a nitro group, or a hydroxyl group, and an imidazole compound represented by a Formula (II) where R2 represents a hydrogen atom, a C1 to C10 alkyl group, a phenyl group, a benzyl group, or a cyanoethyl group, and R3 to R5 each independently represents a hydrogen atom, a nitro group, or a halogen atom, or a C1 to C20 alkyl group, phenyl group, benzyl group, or C1 to C20 acyl group that may have a substituent.

Abstract: It is an object of the present invention to provide a clathrate that suppresses a curing reaction at low temperature to promote an improvement in storage stability (one-component stability), and can effectively cure a resin by heating treatment. A clathrate suitable for the clathrate is a clathrate containing (b1) at least one selected from the group consisting of an aliphatic polyvalent carboxylic acid, 5-nitroisophthalic acid, 5-tert-butylisophthalic acid, 5-hydroxyisophthalic acid, isophthalic acid, and benzophenone-4,4?-dicarboxylic acid; and (b2) at least one selected from the group consisting of an imidazole compound represented by the following formula (I), and 1,8-diazabicyclo[5.4.0]undecene-7, at a molar ratio of 1:1.

Abstract: The present invention provides a liquid curable epoxy resin composition that has excellent storage stability and curing properties and provides a cured product having excellent properties, particularly, excellent organic solvent resistance. For that purpose, a clathrate containing a carboxylic acid compound and at least one selected from the group consisting of an imidazole compound represented by formula (I), wherein R1 to R4 each represent a hydrogen atom or the like, and 1,8-diazabicyclo[5.4.0]undecene-7 (DBU) is mixed in an epoxy resin. The liquid curable epoxy resin composition uses a liquid epoxy resin or an organic solvent.

Abstract: An apparatus for polishing an edge surface of a glass substrate for magnetic recording media. The apparatus includes a grindstone including abrasive grains mixed with a resin. The grindstone is configured to polish at least the edge surface of the glass substrate. The grindstone has a reentrant groove with a bottom surface and sidewall surfaces such that the bottom surface of the reentrant groove contacts the edge surface of the glass substrate and the sidewall surfaces of the reentrant groove contacts chamfered sidewalls of the glass substrate. The reentrant groove and sidewall surfaces are formed in the resin of the grindstone by pressing the glass substrate into the resin of the grindstone with a force higher than a pressing force during polishing.

Abstract: It is to improve the storage stability of a sealant, to retain the flowability of the sealant when sealing, and to achieve an effective curing rate of the sealant by heating to be applicable as a sealant for delicate semiconductors. It is an epoxy resin composition for sealing a semiconductor, comprising the following component (A) and component (B). (A) an epoxy resin, (B) a clathrate complex comprising (b1) an aromatic carboxylic acid compound, and (b2) at least one imidazole compound represented by formula (II) (wherein R2 represents a hydrogen atom, etc.; R3 to R5 represent a hydrogen atom, etc.).

Abstract: The present invention provides a curing catalyst (clathrate compound) for which the curing reaction is suppressed at low temperatures, allowing an improvement in the one-pot stability, but which can effectively cure a resin upon heat treatment. The clathrate compound comprises at least an isophthalic acid compound represented by a formula (1) [wherein R1 represents a C1 to C6 alkyl group or the like] and an imidazole compound represented by a formula (II) [wherein R2 represents a hydrogen atom or a C1 to C10 alkyl group or the like, and R3 to R5 each independently represents a hydrogen atom or a nitro group or the like].

Abstract: A method for etching doughnut-type glass substrates, which comprises laminating a plurality of doughnut-type glass substrates each having a circular hole at its center so that the circular holes form a cylindrical hole, and applying an etching treatment to inner peripheral edge surfaces of the plurality of the laminated doughnut-type glass substrates all at once by means of an etching liquid or an etching gas, wherein the etching liquid or the etching gas is supplied from one end of the cylindrical hole, made to flow in the cylindrical hole, and discharged from the other end of the cylindrical hole so that it is not in contact with exposed main surfaces of the doughnut-type glass substrates at both ends of the laminate consisting of the doughnut-type glass substrates.

Abstract: An apparatus for polishing an edge surface of a glass substrate for magnetic recording media. The apparatus includes a grindstone including abrasive grains mixed with a resin. The grindstone is configured to polish at least the edge surface of the glass substrate. The grindstone has a reentrant groove with a bottom surface and sidewall surfaces such that the bottom surface of the reentrant groove contacts the edge surface of the glass substrate and the sidewall surfaces of the reentrant groove contacts chamfered sidewalls of the glass substrate.

Abstract: A method for manufacturing a doughnut-shaped glass substrate by use of a glass substrate manufacturing apparatus, the glass substrate manufacturing apparatus comprising a work stage, three drilling machines and a conveying device capable of moving the work stage, comprising fixing a glass sheet on the work stage; moving the glass sheet to a position just above the core drill of the first drilling machine by use of the conveying device; partially drilling the glass sheet from downward by use of the core drill of the first drilling machine; moving the glass sheet to a position just under the core drill of the second drilling machine by use of the conveying device; forming the inner circular hole in the doughnut-shaped glass substrate by drilling the partially drilled portion from upward by use of the core drill of the second drilling machine; moving the glass sheet to a position just under the core drill of the third drilling machine by use of the conveying device; and separating the doughnut-shaped glass subst

Abstract: To provide an apparatus for polishing an edge surface of a glass substrate for magnetic recording media and a process for producing a glass substrate for magnetic recording media, whereby with respect to a glass substrate to be used as a substrate for a hard disk, the quality and productivity can be improved without requiring extra effort. In a process for practically producing a hard disk by using a glass substrate 2, the arithmetic average roughness (Ra) required for the outer edge surface of the glass substrate is at most 100 nm. With the roughness of this level, highly productive mechanical polishing by a grindstone is possible. Further, since such mechanical polishing is possible, the productivity can be increased by adopting sheet treatment. Further, by stabilizing the processing margin by employing a grindstone 4 made of resin, variations in the dimensional precision in the individual glass substrates can be minimized.

Abstract: A method for manufacturing a doughnut-shaped glass substrate by use of a glass substrate manufacturing apparatus, the glass substrate manufacturing apparatus comprising a work stage, three drilling machines and a conveying device capable of moving the work stage, comprising fixing a glass sheet on the work stage; moving the glass sheet to a position just above the core drill of the first drilling machine by use of the conveying device; partially drilling the glass sheet from downward by use of the core drill of the first drilling machine; moving the glass sheet to a position just under the core drill of the second drilling machine by use of the conveying device; forming the inner circular hole in the doughnut-shaped glass substrate by drilling the partially drilled portion from upward by use of the core drill of the second drilling machine; moving the glass sheet to a position just under the core drill of the third drilling machine by use of the conveying device; and separating the doughnut-shaped glass subst

Abstract: A doughnut-type glass substrate for a magnetic disk having a circular hole at its center, characterized in that its inner peripheral edge surface is an etched surface with a large number of pits having different curvature radii adjacent to one another, and the proportion of pits having curvature radii r of at most 0.5 ?m is at most 5% to all the pits on the etched surface.

Abstract: A method for coating doughnut-type glass substrates, which comprises laminating a plurality of doughnut-type glass substrates each having a circular hole at its center so that the circular holes form a cylindrical hole, and supplying a coating liquid to an inner peripheral surface of the cylindrical hole in a state where the glass substrates are laminated to coat inner peripheral edge surfaces of the plurality of the doughnut-type glass substrates with the coating liquid.

Abstract: A method for etching doughnut-type glass substrates, which comprises laminating a plurality of doughnut-type glass substrates each having a circular hole at its center so that the circular holes form a cylindrical hole, and applying an etching treatment to inner peripheral edge surfaces of the plurality of the laminated doughnut-type glass substrates all at once by means of an etching liquid or an etching gas, wherein the etching liquid or the etching gas is supplied from one end of the cylindrical hole, made to flow in the cylindrical hole, and discharged from the other end of the cylindrical hole so that it is not in contact with exposed main surfaces of the doughnut-type glass substrates at both ends of the laminate consisting of the doughnut-type glass substrates.

Abstract: A glass substrate for magnetic disks, which is a doughnut-type glass substrate having a cut hole at its center, wherein the inner peripheral edge surface at the cut hole is covered with a coating film formed by curing a silicone resin and providing a contact angle of at least 30°.