Abstract: The plastic optical element has such a characteristic that it will gain a mass increase of no more than 0.1 mass % upon moisture absorption when it is left to stand for 30 days in an atmosphere with a temperature of 40° C. and a relative humidity of 20% and then left to stand for an additional 30 days in an atmosphere with a temperature of 40° C. and a relative humidity of 90%. The plastic optical element includes a plastic substrate and a multi-layered film covering the plastic substrate. The multi-layered film includes a lower inorganic layer formed over the plastic substrate and an upper organic layer formed over the inorganic layer.

Abstract: A resin molded article having excellent mechanical properties, heat resistance, light weight, thermoplasticity, and recyclability, which gives no adverse effects to the environment after its disposal is provided. The resin molded article is produced by molding and crystallizing a composition comprising a crystallizable, biodegradable plastic resin containing a polylactic acid as its main component, a glass fiber, and a hollow glass balloon which has been surface treated with a coupling agent. The article has a heat distortion temperature of at least 80° C. and a density of up to 1.2 g/cm3.

Abstract: There is provided a method of producing a plastic optical component from a plastic material using an injection molding machine. This method removes foreign matter from a molten plastic material having dissolved therein 0.1 mass % or more of carbon dioxide through a filter arranged midway through a passage for the molten plastic material provided in the injection molding machine and injects the molten plastic material into a molding die preliminarily pressurized with a pressurization gas to prevent foaming of the molten plastic material. Even when a high filtration precision filter is provided in the injection molding machine, the filtration pressure loss is low and there is no breakage of a filter. It is also possible to significantly reduce the fraction defective of plastic optical components due to contamination by foreign matter or clouding resulting from foaming of carbon dioxide.

Abstract: A resin molded article and a production method thereof, including the processes of heat-molding a molding material containing a biodegradable resin and a reinforcing fiber or a biodegradable resin, a reinforcing fiber after controlling a water content thereof, or non-controlling. The resin molded article according to the present invention has sufficient heat resistance so that they are not deformed even after being temporarily left in a high temperature environment such as that in an automobile in the daytime in summer seasons and being heated to a high temperature, without deteriorating the properties thereof as members for recording materials, and therefore cause no environmental problems when left in nature since they can be finally decomposed by microorganisms.

Abstract: An object of the present invention is to provide a biaxial oriented polyester film and a method of manufacturing the same, in which sufficient suitability for the longitudinal stretching and transparency can be achieved in a film while a high slidability is ensured. Further, the present invention provides a photographic substrate and a photographic light-sensitive material utilizing the biaxial oriented polyester film having the above-described excellent characteristics. Specifically, a biaxial oriented polyester film and a method of manufacturing the same, a photographic substrate, and a photographic light-sensitive material are provided, and the biaxial oriented polyester film comprises 0.001 to 0.05% by weight of spherical silica particles with a number average particle diameter (Xm) of 0.20 to 0.50 &mgr;m and a particle size distribution represented by the following formula (1): 0.1≦|d90−Xm|/|d10−Xm|≦0.

Abstract: This invention provides a method of producing polyester and charging apparatus therefor capable of producing a high quality polyethylene naphthalate usable for photographic purpose from recovered polyethylene naphthalate which comprises subjecting an ester-forming derivative consisting essentially of naphthalene dicarboxylic acid or its lower alkyl ester and a diol compound consisting essentially of ethylene glycol to ester exchange reaction or esterification to produce polyethylene naphthalate, wherein recovered polyethylene naphthalate resin is charged before beginning of effusion of alcohol or water which is a by-product of the ester exchange reaction or esterification, and a charging apparatus comprising a slidable inner pipe capable of penetrating through a supply valve.

Abstract: In a polymerization apparatus in which the power of a motor is transmitted to a stirrer via oil-lubricated transmission box and speed reduction gear, the temperature of the lubricating oil in the transmission box and speed reduction gear is maintained constant by means of a heat exchanger, the torque between the motor and the transmission box or the speed reduction gear is measured with a torque meter, the viscosity of a reaction mixture is calculated from the measured torque and the number of rotation of the stirrer, and the stirrer is kept revolving until the calculated viscosity of the reaction mixture reaches a prescribed value.

Abstract: A photographic film has a width of 35 mm and comprises a continuous support comprising polyester and at least one photographic layer provided thereon. The support has a thickness of 112 to 128 .mu.m. The polyester has recurring units comprising 60 to 85 molar % of ethylene-2,6-naphthalate unit and 15 to 40 molar % of ethylene terephthalate unit and satisfies the formula (1):-0.65.ltoreq.?NDA!+log ?NET!.ltoreq.0.28 (1)wherein ?NDA! represents a ratio of a number of 2,6-naphthalate unit to a total number of 2,6-naphthalate unit and terephthalate unit, and ?NET! represents a ratio of a number of ethylene unit which has a 2,6-naphthalate unit on one side and a terephthalate unit on the other side to a total number of an ethylene unit in the polyester.

Abstract: A photographic support having good adhesion to a photographic emulsion layer formed thereon without physical surface modification. The support comprises a uniaxially or biaxially stretched polyester film and has at least (1) a main layer containing a polyester and (2) one or two surface layers. At least one of the surface layers comprises a substantially noncrystalline polyester. Furthermore, when used in the form of a roll film, substantially no curling of the support remains upon development.

Abstract: Disclosed is a process for the preparation of polyester having an ethylene-terephthalate recurring-unit in the amount of not less than 60 molar % of the total recurring-unit of the polyester by polymerizing a bifunctional carboxylic acid comprising terephthalic acid and glycol comprising ethylene glycol in the presence of an antimony compound, at least one metal compound selected from the group consisting of a glycol-soluble magnesium compound, a glycol-soluble manganese compound and a glycol-soluble zinc compound, a hindered phenol compound, and a sulphur-containing ester compound, wherein the metal compound, the hindered phenol compound and a sulphur-containing ester compound are employed under the following conditions:0.015.ltoreq.A.ltoreq.0.15 (I)0.01.ltoreq.B.ltoreq.0.2 (II)0.01.ltoreq.C.ltoreq.0.2 (III)0.5.ltoreq.B/C.ltoreq.2.

Abstract: A method for controlling synthesis reaction of a synthetic high molecular resin, the method measuring continuously an infrared spectral absorption of a reaction intermediate product of polycondensation reaction. And the method controls reaction conditions on the basis of the measured infrared spectral absorption.

Abstract: A process for forming a multilayered coating film is disclosed, comprising forming a liquid film of a coating composition, increasing the viscosity of the liquid film, and laminating the liquid film having an increased viscosity onto a support or onto a coating film on a support. A multilayered coating film can thereby be formed easily and efficiently without involving interlaminar mixing between adjacent layers.

Abstract: A process for preparing bis(hydroxyethyl)terephthalate and its low molecular weight oligomers in a reactor equipped with a rectifying column which comprises suspending or dissolving terephthalic acid in molten bis(hydroxyethyl)terephthalate and its low molecular weight oligomers at a temperature above the dew point of ethylene glycol and feeding gaseous or liquid ethylene glycol into the suspension or the solution to react it with the terephthalic acid, where the amount of ethylene glycol fed into the reactor is controlled so as to maintain the temperature inside the rectifying column at a temperature at which the ethylene glycol does not substantially distill off from the rectifying column and the partial pressure of the ethylene glycol is maximized.