Abstract: A ring-shaped glass spacer is to be arranged in contact with a magnetic disk in a hard disk drive device. A film that contains at least one of tin oxide, zinc oxide, and titanium oxide is formed on each surface of a main surface, and an outer circumferential edge surface, and an inner circumferential edge surface of the glass spacer. The thickness of the film on a center portion of the outer circumferential edge surface of the glass spacer is larger than the thickness of the film on a center portion of the inner circumferential edge surface of the glass spacer.

Abstract: The present invention provides dense silica particles with reduced metal impurities. Specifically, the present invention provides a colloidal silica produced by using an alkyl silicate as a starting material, wherein, with respect to a sample prepared by adding, as an internal standard, 1 wt. % of polydimethylsilane to a dried product of the colloidal silica, a peak area value calculated using a formula of a colloidal silica peak area/a polydimethylsilane peak area is 15 or less, the peak areas being determined by an obtained solid-state 29Si-CP/MAS-NMR spectrum. The present invention further provides a method for producing the colloidal silica.

Abstract: A front housing configuring a scroll compressor is provided in its shaft hole with a first bearing, and the front housing rotatably supports a rotation shaft. The first bearing includes a ball bearing having a plurality of balls. First and second seal rings and are provided between an outer ring fixed to the front housing and an inner ring which abuts against an outer peripheral surface of the rotation shaft. A first seal ring disposed on the side of one side surface of the outer ring is provided such that the first seal ring is in non-contact with the inner ring, and the second seal ring disposed on the side of the other side surface of the outer ring abuts against the inner ring.

Abstract: This invention provides a dense, high-purity colloidal silica containing silica secondary particles having a branched and/or bent structure, and a production method thereof. Specifically, this invention provides a method for producing a colloidal silica, comprising the steps of 1) preparing a mother liquid containing an alkali catalyst and water, and having a pH of 9 to 12; and 2) adding a hydrolysis liquid obtained by hydrolysis of an alkyl silicate to the mother liquid, wherein the step of adding the hydrolysis liquid to the mother liquid sequentially comprises A) step 1 of adding the hydrolysis liquid until the pH of the resulting liquid mixture becomes less than 7; B) step 2 of adding an aqueous alkali solution until the pH of the liquid mixture becomes 7 or more; and C) step 3 of adding the hydrolysis liquid while maintaining the pH of the liquid mixture at 7 or more, and a colloidal silica containing silica secondary particles having a branched and/or bent structure, obtained by this method.

Abstract: A front housing configuring a scroll compressor is provided in its shaft hole with a first bearing, and the front housing rotatably supports a rotation shaft. The first bearing includes a ball bearing having a plurality of balls. First and second seal rings and are provided between an outer ring fixed to the front housing and an inner ring which abuts against an outer peripheral surface of the rotation shaft. A first seal ring disposed on the side of one side surface of the outer ring is provided such that the first seal ring is in non-contact with the inner ring, and the second seal ring disposed on the side of the other side surface of the outer ring abuts against the inner ring.

Abstract: This invention provides a dense, high-purity colloidal silica containing silica secondary particles having a branched and/or bent structure, and a production method thereof. Specifically, this invention provides a method for producing a colloidal silica, comprising the steps of 1) preparing a mother liquid containing an alkali catalyst and water, and having a pH of 9 to 12; and 2) adding a hydrolysis liquid obtained by hydrolysis of an alkyl silicate to the mother liquid, wherein the step of adding the hydrolysis liquid to the mother liquid sequentially comprises A) step 1 of adding the hydrolysis liquid until the pH of the resulting liquid mixture becomes less than 7; B) step 2 of adding an aqueous alkali solution until the pH of the liquid mixture becomes 7 or more; and C) step 3 of adding the hydrolysis liquid while maintaining the pH of the liquid mixture at 7 or more, and a colloidal silica containing silica secondary particles having a branched and/or bent structure, obtained by this method.

Abstract: The present invention provides dense silica particles with reduced metal impurities. Specifically, the present invention provides a colloidal silica produced by using an alkyl silicate as a starting material, wherein, with respect to a sample prepared by adding, as an internal standard, 1 wt. % of polydimethylsilane to a dried product of the colloidal silica, a peak area value calculated using a formula of a colloidal silica peak area/a polydimethylsilane peak area is 15 or less, the peak areas being determined by an obtained solid-state 29Si-CP/MAS-NMR spectrum. The present invention further provides a method for producing the colloidal silica.

Abstract: A cathode-ray tube according to the present invention is provided with a phosphor screen comprising phosphors A, B, and C, wherein each of the phosphors A and B constitute 5 to 15% by weight and, the phosphor C constitutes 70 to 90% by weight. The phosphor A is a bluish white-emitting phosphor (Y.sub.1-x-y Gd.sub.x Tb.sub.y).sub.2 O.sub.2 S (0.ltoreq.X.ltoreq.0.999999 and 0.000001.ltoreq.Y.ltoreq.0.001), the phosphor B is at least one of a blue-emitting silver-activated hexagonal zinc sulfate (ZnS:Ag) phosphor, etc., and the phosphors C is a yellow-emitting phosphor (In.sub.1-p-r M.sub.p TB.sub.q Eu.sub.r BO.sub.3) (wherein M is at least one element selected from the group consisting of Sc, Lu, Y, Gd, and Ga, and p, q, and r satisfy 0.ltoreq.p.ltoreq.0.2, 0.0005.ltoreq.q.ltoreq.0.05, and 0.001.ltoreq.r.ltoreq.0.1). The cathode-ray tube of the present invention is a phosphor screen which is free from toxicity and has good flickering and brightness characteristics and high current dependence of brightness.

Abstract: High strength and toughness cobalt-free maraging steel containing, by mass, 11 to 15% Ni, 0.5 to 4% Cr, 0.5 to 5.5% Mo, 0.5 to 2% Ti, 0.05% max. C, 1% max. Mn and 0.5% max. Si, the balance consisting of iron and unavoidable impurities. The amounts of Ni, Mo and Ti in the steel have the following relationship to one another: ##EQU1## A process for heat treating this steel is also disclosed.

Abstract: Disclosed is a white luminescent phosphor for use in a cathode ray tube, which comprises a mixture of at least one phosphor having a composition of the following formula:In.sub.1-p-q-r M.sub.p Eu.sub.q Tb.sub.r BO.sub.3wherein M represents at least one element selected from the group consisting of Sc, Lu, Y, La, Gd and Ga; and each of p, q and r represents a number satisfying the relationships of p.gtoreq.0, q.gtoreq.0, r.gtoreq.0 and 0<p+q+r<1, and having a 10% afterglow period of 10 milliseconds or longer, and a blue luminescent phosphor having the composition of ZnS:Ag.