Abstract: The amount of dimming components originating in an ultraviolet-curing resin and adhering to a quartz tube is reduced, and a decline in the ultraviolet transmittance is prevented, during ultraviolet-curing of a resin coated on a liner body through an ultraviolet-transmitting tubular member placed inside a curing apparatus and of curing ultraviolet-curing resin by irradiating ultraviolet rays from outside the ultraviolet-transmitting tubular member. Embodiments include coating the inner surface of the ultraviolet-transmitting tubular member with titanium and employing an atmosphere of lover 0.1% oxygen.

Abstract: An optical fiber preform 2 having a viscosity ratio R&eegr;=&eegr;0/&eegr;t of 2.5 or less between the core average viscosity &eegr;0 and the total average viscosity &eegr;t is prepared, and is drawn by a drawing furnace 11 so as to yield an optical fiber 3, which is then heated to a temperature within a predetermined range so as to be annealed by a heating furnace 21 disposed downstream the drawing furnace 11. Here, upon annealing in the heating furnace 21, the fictive temperature Tf within the optical fiber lowers, thereby reducing the Rayleigh scattering loss. At the same time, the viscosity ratio condition of R&eegr;≦2.5 restrains the stress from being concentrated into the core, thereby lowering the occurrence of structural asymmetry loss and the like. Hence, anoptical fiber which can reduce the transmission loss caused by the Rayleigh scattering loss and the like as a whole, and a method of making the same can be obtained.

Abstract: An apparatus for producing optical fiber ribbons which has a optical fiber gathering device, one or more coating applicators and a turn roller arranged in a straight line, with one or more alignment guide in plate form being provided on a travelling line of optical fibers or optical fiber ribbons upstream of the coating applicator. The alignment guide is chamfered to arch form on the side that contacts the optical fibers or the optical fiber ribbons. The alignment guide suppresses the optical fibers or the optical fiber ribbons from vibrating in a direction perpendicular to the direction of the arrangement of the optical fibers or the optical fiber ribbons.

Abstract: A collectively coating die device (2) is provided for applying coating resin in a lump to coated optical fibers (1) arranged in parallel on one and the same plane so as to form a plurality of optical fiber ribbons (16) at the same time. The collectively coating die device (2) has a nipple portion (9) and a die portion (10), a resin accumulation space (8) formed between the nipple portion (9) and the die portion (10). The nipple portion (9) has two parallel planes and having a plurality of optical fiber passageways (13) shaped like ellipses in section and provided in the direction perpendicular to the planes. The die portion (10) has two parallel planes and has a plurality of optical fiber passageways (14) shaped like ellipses in section and is provided in the direction perpendicular to the planes. Each of the optical fiber passageways (13) of the nipple portion (9) has a tapered portion.

Abstract: When drawing an optical fiber from a preform, positive and negative dispersion sections of an optical fiber are provided, respectively, with target glass diameters different from each other, whereby the positive and negative dispersion sections attain their respective desirable values of chromatic dispersion. Also, the positive and negative dispersion sections and a transient section therebetween are provided, respectively, with values of control constant different from each other, which are used to converge the measured glass diameter to said target diameter, for adjusting the drawing speed, whereby the transient section is shortened. Alternatively, the positive and negative dispersion sections of the optical fiber are provided with respective target drawing speeds different from each other, whereby the transient section is shortened.

Abstract: An optical fiber making apparatus has a main pipe connected to the furnace core tube, two branch pipes branching from the main pipe, and a gas source, a valve and a flow meter connected to each of the branch pipes. The flows or compositions of the inert gases supplied from the gas sources into the furnace core tube are varied. This changes the amount of heat applied to the lower end of the optical fiber preform, without depending solely on the main heater, to adjust the draw tension and thereby change the local chromatic dispersion along the longitudinal direction of the optical fiber being manufactured.

Abstract: Disclosed is a recording sheet for ink-jet recording comprising a support, and provided on one side of the support, an ink receiving layer, wherein the layer swelling amount of the ink receiving layer is 20 to 500 cc/m.sup.2, and the layer solubility time of the ink receiving layer is 10 minutes or more.

Abstract: A recording sheet for ink-jet recording is disclosed which comprises a support, and provided thereon, an ink receiving layer, wherein the ink receiving layer contains a water soluble polymer, a polymer latex and gelatin.

Abstract: A recording sheet for ink-jet recording comprising a support, and provided on one side of the support, an ink receiving layer, wherein the ink receiving layer contains a compound represented by the following formula I: ##STR1## wherein Q.sup.1 and Q.sup.2 independently represent a non-metallic atomic group necessary to form an acidic nitrogen-containing heterocyclic ring; L.sup.1, L.sup.2, and L.sup.3 independently represent a substituted or unsubstituted methine group; M represents a cationic group; m represents an integer of 0 to 4; and n represents a number necessary to neutralize the charge of the molecule.

Abstract: An ink-jet recording sheet is disclosed, comprising a support having on at least one side thereof an ink receiving layer, wherein the ink receiving layer comprises a gelatin having an isoelectric point of 5.5 to 9.6 and a water-soluble cationic polymer.

Abstract: In a resin coating applicator, a holder 14 is fixed on a base 15 fitted to a drawing machine, and in the holder 14, hot water can be circulated from an inlet 18. The inner circumferential surface of the holder 14 is formed into a tapered shape so that the outer circumferential surface of a cup-like member 4 of a cartridge type coating sub-assembly 1 is fitted to the holder 14. The respective outer circumferential surfaces of a nipple 2 and a coating die 3 are cylindrical so as to be fitted to the inner circumferential surfaces of an inner cylindrical member 6, and they are positioned by a step portion. Further, they are pressed from the upper and lower sides by the bottom portion of the cup-like member 4 and a lid member 5. The lid member 5 is fastened to the cup-like member 4 integrally by a thread.

Abstract: The present invention relates to an optical fiber coating method and an apparatus therefor which can form high quality coating layer on an optical fiber (12) by preventing non-concentricity of a coating resin (14) applied on the optical fiber (12) and admixing of bubble.

Abstract: An ink-jet recording method is disclosed, which comprises the step of jetting a water-based ink on a recording sheet, the recording sheet comprising a support and provided thereon, an ink receiving layer containing a binder, an anionic fluorine-containing surfactant and a cationic fluorine-containing surfactant, wherein the content ratio of the anionic fluorine-containing surfactant to the cationic fluorine-containing surfactant is 1:10 to 10:1 in terms of mole ratio.

Abstract: In order to provide an improved process for the production of a glass preform for an optical fiber which includes substantially no bubble formation therein and also has a substantially uniform shape, the present invention provides a process for the production of a glass preform which is at least partially formed from silica. In particular, a body is formed on a rod by depositing fine glass particles thereon, preferably by the vapor phase reactions, and heating the body to vitrify under a reduced atmosphere or a vacuumed atmosphere so that the glass preform is produced.

Abstract: A furnace and method for drawing an optical fiber is provided. The furnace included a furnace core chamber in which a preform is inserted into the chamber through the upper end thereof and a drawn optical fiber is pulled out of the chamber through an opening positioned at the lower end thereof. The furnace also includes a gas-supply means for introducing an inert gas into the furnace core chamber to thus establish an inert gas atmosphere within the chamber, and a heater for heating the preform so that the lower part of the preform is molten and drawn into the optical fiber, which is positioned around the outer periphery of the furnace core chamber. The furnace further includes an inner furnace core tube, which is positioned within the furnace core chamber and which has a cylindrical part whose lower part is communicated to the opening of the furnace core chamber and a funnel-like part which is positioned on the upper end of the cylindrical part.

Abstract: An optical fiber preform manufacturing apparatus which continuously monitors the weight of a preform during manufacturing by a load cell without increasing the offset amount of the preform. The preform manufacturing apparatus includes a rotary chuck unit vertically moved by an elevating unit and a rod gripped by the rotary chuck unit and vertically extending downward. At the time of manufacturing a preform, the elevating unit and the rotary chuck unit are driven to rotate and move a starting rod suspended from the lower end of the rod upward. A support plate is fixed to the rotary chuck unit. Three or more load cells are arranged between the support plate and an elevating plate of the elevating unit. The rotary chuck unit is firmly supported by these load cells, so that the rotating shaft is not inclined. A hole is formed in the elevating plate, and the rotary chuck unit extends through the hole with a gap therebetween.

Abstract: The ferrule for optical connector according to this invention comprises a first grip portion having first through holes for insertion of optical fibers and gripping part of said optical fibers apart a predetermined distance from the distal ends of optical fibers; a second grip portion arranged along the insertion direction of optical fibers together with the first grip portion and opposed to the first grip portion through a first space. The second grip portion has second through holes for the optical fibers set through the first through holes to be further introduced therethrough, and grips the vicinity of the distal ends of optical fibers; and a pedestal portion projecting from a surface of the first grip portion.

Abstract: A method for processing an exposed silver halide color photographic photosensitive material is disclosed, which comprises the step of developing the exposed material with a color developer in a color development tank of an automatic developing apparatus, the developer in the developer tank being replenished with replenishing water and a solid color developing composition comprising a p-phenylenediamine color developing agent having a water-solubilizing group, wherein the replenishing amount of the water is 30 to 75 ml per m.sup.2 of the material processed and the replenishing amount of the color developing agent is 0.024 to 0.066 mol per liter of the replenishing amount of the water.

Abstract: A device to dissolve solid processing agents and to replenish the dissolved processing agents to an automatic processing apparatus for a silver halide photographic light-sensitive material which has a processing tank and a circulating path for a processing solution provided in the processing tank. The device includes a dissolving tank for storing a dissolved solution therein, and a processing solution supplier provided between the processing tank and the dissolving tank independent of the circulating path, which supplies the processing solution from the processing tank to the dissolving tank. The device further includes a replenisher to replenish the dissolved solution from the dissolving tank to the processing tank. The dissolving tank and the processing tank are communicated through another circulating path.

Abstract: There is provided a process for the consolidation of a porous glass preform for an optical fiber by heating the preform under an increasing pattern of a heating temperature in a vacuum furnace comprising a muffle tube therein characterized in that the increasing pattern is divided into two steps consisting of a first step and a second step with regard to time, and the first step has a pattern in which the heating temperature is increased under a reduced pressure atmosphere and a gas comprising at least an inert gas is supplied to the vacuum furnace under the reduced pressure atmosphere and the second step has a pattern in which the heating temperature is increased under a reduced pressure atmosphere in which a gas comprising a smaller amount of an inert gas than that of the first step is supplied to the vacuum furnace or under a vacuum pressure atmosphere in which no gas is supplied to the vacuum furnace.