Abstract: An optical communication device substrate made of ceramic or glass-ceramic having a negative thermal expansion coefficient in the range of −10 to −120×10−7/° C. in a temperature range of −40 to 100° C., treated with a solution containing at least one organic silicon compound selected from the group consisting of siloxane compounds and silazane compounds.

Abstract: Crystallized glass is formed by precipitating &bgr;-spodumene solid solution or &bgr;-quartz solid solution, and contains, by mass percent, 55-72% SiO2, 14-30% Al2O3, 2.9-6.0% Li2O, and 1.0-10.0% K2O, wherein a mass ratio between Li2O and K2O (Li2O/K2O) is 2.2 or less.

Abstract: A crystallized glass is provided. A &bgr;-quartz solid solution or a &bgr;-eucryptite solid solution is precipitated as a main crystal. The crystallized glass has a crystallization degree not less than 70 mass %, a crystal grain size not more than 0.5 &mgr;m, substantially no gap or crack occurring at boundaries of crystal grains. The crystallized glass also has a thermal expansion coefficient being negatively greater than −10×10−7/° C. within a temperature range of −40° C.˜100° C., a hysteresis of the thermal expansion coefficient within the temperature range being not more than 10 ppm, and a temperature dependence of the refractive index being not more than 13×10−6/° C.

Abstract: A fire-protection glass product having a heat shielding characteristic comprises a plurality of fireproof glass plates, a resin intermediate layer interposed between adjacent ones of the glass plates, and a heat-ray reflection film. The heat-ray reflection film is formed on the surface of at least one of the glass plates, and has a reflectance of 70% or more for a light of the wavelength of 2500 nm and an average transmittance of 60% or more for visible rays. The resin intermediate layer is made of a material selected from fluorocarbon resin, polycarbonate resin, and polyethylene terephthalate resin. At least one of the fireproof glass plates may be made of a heat-resistant transparent crystallized glass plate. The heat-ray reflection film may be formed on at least one of opposite surfaces of the fireproof glass plate.

Abstract: A substrate glass for a multilayer filter is 150 nm or less in flatness within a circle of diameter 50 mm and has a thermal expansion coefficient of 90 to 130×10−7/° C. at temperatures of −30 to 70 ° C. The substrate glass 150 nm or less in flatness within a circle of diameter 50 mm provides less variations in thickness of film layers. When a plurality of multilayer filters are fabricated from a single sheet of the substrate glass, variations in center wavelength fall within the range of ±100 pm among the multilayer filters, thereby providing improved production yields for the multilayer filters.

Abstract: In a glass preform (10) to be subjected to fiber-drawing, use is made of a cylindrical glass tube (21) whose one end in an axial direction is sealed. A plurality of glass capillaries (22) extend in the glass tube in the axial direction. The glass capillaries are fused to one another into an integral structure. The glass capillaries have air holes periodically arranged on a plane perpendicular to the axial direction, respectively.

Abstract: An optical waveguide member is inserted into a tubular member. The tubular member is elongated with heating and fusion-bonded to the optical waveguide member. Thus, a formed body is obtained. The formed body is cut into a predetermined length to obtain an optical waveguide member. The tubular member is preferably made of a crystallized glass with crystals deposited therein at least in the state of the formed body.

Abstract: In an Li2O—Al2O3—SiO2 transparent crystallized glass, &bgr;-quartz solid solution is produced as main crystals, an average coefficient of linear thermal expansion within a range between 30 and 380° C. is −10˜10×10−7/°C., and &bgr;-OH in an amount of 0.28/mm or more is contained. Preferably, the content of each component of Li2O, SiO2, and Al2O3 satisfies, by weight ratio, the relationship given by 0.058≧{Li2O/(SiO2+Al2O3)}≧0.031.

Abstract: An optical communication device substrate made of ceramic or glass-ceramic having a negative thermal expansion coefficient in the range of −10 to −120×10−7/° C. in a temperature range of −40 to 100° C., treated with a solution containing at least one organic silicon compound selected from the group consisting of siloxane compounds and silazane compounds.

Abstract: A crystallized glass is provided. A &bgr;-quartz solid solution or a &bgr;-eucryptite solid solution is precipitated as a main crystal. The crystallized glass has a crystallization degree not less than 70 mass %, a crystal grain size not more than 0.5 &mgr;m, substantially no gap or crack occurring at boundaries of crystal grains. The crystallized glass also has a thermal expansion coefficient being negatively greater than −10×10−7/° C. within a temperature range of −40° C.˜100° C., a hysteresis of the thermal expansion coefficient within the temperature range being not more than 10 ppm, and a temperature dependence of the refractive index being not more than 13×10−6/° C.

Abstract: Li2O—Al2O3—SiO2 crystallized glass is provided which has clarity and glass characteristics equivalent to or superior to a conventional crystallized glass, even when the content of As2O3 is decreased. The Li2O—Al2O3—SiO2 crystallized glass consists essentially of, by weight, 60 to 75% SiO2, 17 to 27% Al2O3, 3 to 5% Li2O, 0 to 0.9% MgO, 0 to 0.9% ZnO, 0.3 to 5% BaO, 0 to 3% Na2O, 0 to 3% K2O, 0 to 4% TiO2, 1 to 4% ZrO2, 0 to 4% P2O5, 0.05 to 2% Sb2O3, 0 to 0.9% MgO+ZnO, and 0 to 4% Na2O+K2O.

Abstract: In order to provide a tubular or a rod-like ceramic article which is opaque to a visible light and which enables easy and efficient measurement and inspection of its internal structure, the tubular or the rod-like ceramic article opaque to a visible light is made of an infrared transmitting ceramics having a transmittance not less than 45% for an infrared ray having a wavelength of 1500 nm and incident from the air when the thickness is equal to 1 mm. Preferably, the ceramic article is made of an infrared transmitting ceramics which satisfies the condition given by (1−R)2≧0.84 and &mgr;≦0.7/mm where R represents a reflectance at 1550 nm and &mgr; represents a sum of scattering coefficient and an absorption coefficient.

Abstract: Li2O—Al2O3—SiO2 crystallized glass is provided which has clarity and glass characteristics equivalent to or superior to a conventional crystallized glass, even when the content of As2O3 is decreased. The Li2O—Al2O3—SiO2 crystallized glass contains, by weight, 0.05 to 4% Sb2O3, in which the content of &bgr;-OH is 0.3 to 4/mm.

Abstract: A temperature compensating member which comprises a polycrystalline body containing, as a main crystal, one of &bgr;-quartz solid solution and &bgr;-eucryptite solid solution, and it has a value less than 3.52 Å as an interplanar spacing of the crystal planes giving a main peak in X-ray diffraction measurement, and has a negative coefficient of thermal expansion.

Abstract: In an Li2O—Al2O3—SiO2 transparent crystallized glass with &bgr;-quartz solid solution precipitated as main crystals, the Li+ concentration ratio an at a position of 50 nm from the surface of the glass is equal to 0.80 or less where the Li+ concentration at a position of 2000 nm from the surface is supposed to be equal to 1.

Abstract: In order to provide a ferrule for an optical-fiber connector used for good organization of an optical communication network, the ferrule for an optical-fiber connector is made of a crystallized glass having a composition which consists essentially of, by weight percent, 60-70% of SiO2, 16-25% of Al2O3, 1.5-3% of Li2O, 0.5-2.5% of MgO, 1.3-4.5% of TiO2, 0.5-3% of ZrO2, 2-6.5% of TiO2+ZrO2, 1-5.5% of K2O, 0-7% of ZnO, and 0-3% of BaO. The crystallized glass includes 30-70 volume % precipitation of &bgr;-spodumene solid solution or &bgr;-quartz solid solution having an average grain size not greater than 2 &mgr;m. In addition, the crystallized glass has a bend strength of 200 MPa or more and a thermal expansion coefficient of −10˜50×10−7/° C. at a temperature between −50 and 150° C.

Abstract: A process for producing an .alpha.,.beta.-unsaturated nitrile from propylene, isobutylene or tert-butyl alcohol in an industrial fluidized reactor with the step of feeding methanol and an oxygen-containing gas in the course of the whole contact time of the reactor and reacting unreacted ammonia with the methanol and the oxygen-containing gas, which can reduce the amount of unreacted ammonia without lowering the yield of the nitrile; and an industrial process of conducting the above production in an industrial fluidized reactor having an inner diameter of 3 m or above and filled with a molybdenum-bismuth catalyst supported on silica, which can prevent the feed opening of a dispersing nozzle for the methanol from clogging with molybdenum oxides to attain constant reduction in the amount of unreacted ammonia.

Abstract: A top plate (3) of a low-expansion crystallized glass of deep color, with a first enamel coating coated on a heating portion (5, 7, 9, 11) of the plate and a second enamel coating coated on a non-heating portion (13) around and other than the heating portion. The first enamel coating consists essentially, by weight, of 40 to 98% glass content, 5 to 55% at least one of ZrSiO.sub.4 and ZrO.sub.2 crystals, and 0 to 54% coloring pigment. The second enamel coating consists essentially, by weight, of 30 to 94% glass content, 5 to 69% TiO.sub.2 crystals, 0 to 34% coloring pigment.

Abstract: In order to provide an enamel frit composition capable of preventing a hue of a low-expansion crystallized glass plate of a dark color from being seen through an enamel coating without increasing the thickness of the enamel coating and the mixing ratio of a coloring pigment as well as to provide an enamel-coated low-expansion crystallized glass plate using the above-mentioned composition, the enamel frit composition for a low-expansion crystallized glass essentially consists, by weight, of 30-94 wt % glass powder, 5-69 wt % TiO.sub.2 powder, and 0.05-34 wt % coloring pigment.

Abstract: In order to provide an enamel frit composition for a low-expansion crystallized glass, capable of producing an enamel coating excellent in abrasion resistance and acid resistance without occurrence of cracks by using glass powder which does not contain any harmful component such as PbO, and to provide an enamel-coated low-expansion crystallized glass plate using the enamel frit composition, the enamel frit composition for a low-expansion crystallized glass essentially consists 40-98 wt % glass powder, 1-55 wt % coloring pigment, and 0-54 wt % filler. The glass powder consists, by weight, of 55-72% SiO.sub.2, 4-8% Al.sub.2 O.sub.3, 14-22% B.sub.2 O.sub.3, 2-4% BaO, 5.1-15% Na.sub.2 O, 0-2% Li.sub.2 O, 0-2.8% K.sub.2 O, and 0-2% F.sub.2.