Abstract: An aromatic polycarbonate film having excellent transparency and surface smoothness as well as good lubricity useful for optical use through solving the problems of defects such as scratches, wrinkles or abrasions in the production processes and processing processes of the aromatic polycarbonate film for optical use, by specified quality about the concavo-convex forms on both the surfaces of the aromatic polycarbonate film, and by employing specific drying conditions in the drying processes after casting from a solution in a solution-casting film-making method of an aromatic polycarbonate solution.

Abstract: A biaxially oriented polyethylene-2,6-naphthalate film suitable for producing magnetic recording media wherein the film has a Young's modulus of at least 550 kg/mm.sup.2 in the longitudinal direction and a Young's modulus of at least 800 kg/mm.sup.2 in the transverse direction with the Young's modulus in the transverse direction being greater than the Young's modulus in the longitudinal direction by more than 200 kg/mm.sup.2 ; a surface roughness Ra of 1-12 nm; and low heat shrinkage. The film also contains 0.005-2% by weight inorganic or organic fine particles.

Abstract: A biaxially oriented polyester film which has excellent resistances to dry heat deterioration and wet heat deterioration, which can withstand the use in an atmosphere of relatively high moisture content, and which is useful, for example, as an electrical insulating film, a film for transparent electrode, a film for absorption of electromagnetic wave (e.g. a film used as an inspection window of microwave oven) and a reflection film. This polyester contains ?ethylene-2,6-naphthalenedicarboxylate as the main recurring unit.! 99.5 to 95 mole % of ethylene-2,6-naphthalenedicarboxylate and 0.5 to 5 mole % of ethylene-2,7-naphthalenedicarboxylate and has a density of 1.355 to 1.370 g/cm.sup.3 and an intrinsic viscosity of 0.62 to 0.90. The polyester film has an amount of terminal carboxyl in the polyester of 40 eg/10.sup.6 g or less and an amount of oligomers of 2.0 mg/m.sup.2 film or less.

Abstract: A magnetic recording tape or disk formed from a biaxially oriented laminated polyester base film which comprises a layer (A) of a polyester consisting essentially of 2,6-naphthalenedicarboxylic acid and ethylene glycol components and a layer (B) of a copolyester consisting essentially of 2,6-naphthalenedicarboxylic acid, ethylene glycol, and diethylene glycol components, wherein the copolyester contains 1-5% by weight of the diethylene glycol component, based on the weight of the layer (B) copolyester, layer (B) being present on one or both surfaces of layer (A).

Abstract: Provided is a biaxially oriented, unidirectionally long polyethylene-2,6-naphthalenedicarboxylate film having the following characteristic properties;(A) both the Young's modulus in the longitudinal direction and the Young's modulus in the transverse direction are at least 600 kg/mm.sup.2, and the Young's modulus in the longitudinal direction is greater than the Young's modulus in the transverse direction,(B) the heat shrinkage factor in the transverse direction when the film has been treated under no load at 105.degree. C. for 30 minutes is at least 1%, and(C) the surface roughness Ra of one surface of the film is up to 5 nm, anda magnetic recording tape obtained by forming a thin magnetic metal film on the above film undergoes no curling, has high coercive force, has excellent electromagnetic conversion characteristic and permits high-density recording for a long period of time.

Abstract: A biaxially oriented polyethylene-2,6-naphthalate film suitable for producing magnetic recording media wherein the film has a Young's modulus of at least 550 kg/mm.sup.2 in the longitudinal direction and a Young's modulus of at least 800 kg/mm.sup.2 in the transverse direction with the Young's modulus in the transverse direction being greater than the Young's modulus in the longitudinal direction by more than 230 kg/mm.sub.2, a surface roughness Ra of 1-12 nm; and low heat shrinkage. The film also contains 0.005-2% by weight inorganic or organic fine particles.

Abstract: A biaxially oriented polyethylene-2,6-naphthalenedicarboxylate film, which can be used as a base film for a recording medium capable of high-density recording, characterized in that when h (unit: nm) stands for a height of a protrusion formed on the film surface, the numbers of protrusions in the range of 1.ltoreq.h<50, 50.ltoreq.h<100, and 100.ltoreq.h fall each within a specified range, that the film has a plane orientation coefficient (NS) and an average refractive index (n.sub.a) which satisfy the relationship NS.gtoreq.1.607n.sub.a -2.434, that the film has a surface roughness (Ra) of 2-10 nm and that the film has a heat shrinkage in the longitudinal direction of 0.08% or less when heat-treated under no load at 70.degree. C. for 1 hour.

Abstract: Provided is a biaxially oriented, unidirectionally long polyethylene-2,6-naphthalenedicarboxylate film having the following characteristic properties;(A) both the Young's modulus in the longitudinal direction and the Young's modulus in the transverse direction are at least 600 kg/mm.sup.2, and the Young's modulus in the longitudinal direction is greater than the Young's modulus in the transverse direction,(B) the heat shrinkage factor in the transverse direction when the film has been treated under no load at 105.degree. C. for 30 minutes is at least 1%, and(C) the surface roughness Ra of one surface of the film is up to 5 nm, anda magnetic recording tape obtained by forming a thin magnetic metal film on the above film undergoes no curling, has high coercive force, has excellent electromagnetic conversion characteristic and permits high-density recording for a long period of time.

Abstract: A laminated polyester film for use in a magnetic recording medium, which comprises (A) a first layer of a first polyester which contains at least 95 mol %, based on the total content of its dicarboxylic acid components, of a 2,6-naphthalenedicarboxylic acid component and whose main recurring unit is composed of ethylene-2,6-naphthalenedicarboxylate, and (B) a second layer of a second polyester containing 93 to 99 mol %, based on the total content of its recurring units, of an ethylene-2,6-naphthalenedicarboxylate recurring unit. The second layer is laminated on at least one surface of two surfaces of the above first layer.

Abstract: A magnetic recording tape, in particular a VTR tape, comprising;(A) a substrate composed of a biaxially oriented polyethylene-2,6-naphthalate film of which(a) the Young' modulus in the longitudinal direction is at least 650 kg/mm.sup.2, the Young' modulus in a transverse direction is the same as, or greater than, the Young's modulus in the longitudinal direction,(b) the heat shrinkage in the transverse direction is in the range of 1.0 to 3.0% when treated at 100.degree. C. for 30 minutes,(c) the surface roughness, Ra, is not more than 0.005 .mu.m, and(d) the amount of bled-out oligomer is not more than 0.01 area % when treated in air at 160.degree. C. for 5 minutes,(B) a thin magnetic metal layer having a thickness of 100 to 1,500 nm and formed on one surface of the substrate, and(C) a lubricant-containing thin organic polymer layer having a thickness of not more than 1 .mu.

Abstract: A biaxially oriented, unidirectionally long polyethylene-2,6-naphthalate film,(A) which contains(a) 0.05 to 0.4% by weight of first inert solid particles having an average particle diameter of 0.05 to 0.3 .mu.m, and(b) 0.005 to 0.05% by weight of second inert solid particles having an average particle diameter of 0.3 to 1.0 .mu.m, this average particle diameter being greater than the average particle diameter of the first inert solid particles by at least 0.2 .mu.m, wherein:(B) the Young's modulus in the length direction is at least 650 kg/mm.sup.2, the Young's modulus in the width direction is at least 600 kg/mm.sup.2, the Young's modulus in the length direction is greater than the Young's modulus in the width direction,(C) the heat shrinkage factor in the length direction in heat treatment at 70.degree. C. for 1 hour under no load is not more than 0.08%, and(D) the surface roughness, Ra, is 3 to 10 nm; and a magnetic tape obtained therefrom.

Abstract: A biaxially oriented polyester film, (A) which is formed from polyethylene-2,6-naphthalenedicarboxylate containing 0.01 to 1% by weight of inert solid fine particles having an average particle size of 0.05 to 3 .mu.m, (B) which has a refractive index, in a film thickness direction, of at least 1.498, and (C) which has a Young's modulus, at least in one direction, of at least 700 kg/mm.sup.2 ; and a process for the production thereof. This film is useful as a magnetic recording medium, particularly as a base film excellent in abrasion resistance and tear resistance.

Abstract: An oriented polyester film (A) which comprises modified polyethylene-2,6-naphthalenedicarboxylate containing a 4,4'-diphenyldicarboxylic acid component and having a heat of crystallization of 16 to 25.5 Joule/g, and (B) which is biaxially oriented; and an oriented polyester film (A') which comprises modified polyethylene-2,6-naphthalenedicarboxylate containing of a glycol component derived from a compound represented by the following formula, ##STR1## wherein each of n and m is independently a positive number of 1 to 9 as an average, provided that m+n equals 2 to 9 as an average, and having a heat of crystallization of 6 to 20 Joule/g, and (B) which is biaxially oriented. These films are useful as a base film for a magnetic recording tape or as an electric insulation film.

Abstract: A magnetic tape for audio cassettes wherein a magnetic layer is provided on base film characterized in that the a base film, is biaxially oriented polyethylene-2,6-naphthalate film having a Young's modulus in the longitudinal direction of 850 Kg/mm.sup.2 or more, a Young's modulus in the transverse direction of 550 Kg/mm.sup.2 or more a surface roughness Ra in the range of 0.015 to 0.040 .mu.m, and a thermal shrinkage rate in the longitudinal direction of 0.3% or less in a case where it was held at a temperature of 100.degree. C. for 1 hour.A magnetic tape for audio cassettes is provided which is capable of long-time recording and wherein deterioration of magnetic characteristics does not easily occur in use, storage and the like at a high temperature, for example in the open during summer or in cars, compared to conventional ones.

Abstract: An oriented polyester film (A) which comprises modified polyethylene-2,6-naphthalenedicarboxylate containing a 4,4'-diphenyldicarboxylic acid component and having a heat of crystallization of 16 to 25.5 Joule/g, and (B) which is biaxially oriented; and an oriented polyester film (A') which comprises modified polyethylene-2,6-naphthalenedicarboxylate containing of a glycol component derived from a compound represented by the following formula, ##STR1## wherein each of n and m is independently a positive number of 1 to 9 as an average, provided that m+n equals 2 to 9 as an average and having a heat of crystallization of 6 to 20 Joule/g, and (B) which is biaxially oriented. These films are useful as a base film for a magnetic recording tape or as an electric insulation film.

Abstract: The present invention lies in a process for modifying the surface of a molded article, which process comprises irradiating the surface of a molded article composed of an aromatic polymer or a polymer composition containing said aromatic polymer, with an ultraviolet laser beam having a wavelength of about 150 nm-380 nm at a fluence at least lower than the threshold to modify the surface as compared with the condition before the irradiation. The process makes it possible to modify the condition of the laser beam-irradiated surface portions of the molded article to, for example, a white color or black color, whereby the molded article can be endowed with functions and properties required in its use in various applications.

Abstract: An apparatus for detecting a flameout in an internal combustion engine includes a rotational speed sensor for detecting engine rotational speed and for generating an electrical signal corresponding to the engine rotational speed. A sensor is provided for detecting the air-fuel ratio of the engine exhaust gas and for generating an output electrical signal corresponding to the air-fuel ratio. An engine load sensor arrangement detects a load state of the internal combustion engine and generates an output electrical signal corresponding to the load state. A control arrangement is provided for comparing the output signal from the exhaust gas sensor with the output signal from the engine load sensor arrangement when the exhaust gas sensor indicates a lean mixture. The control arrangement uses this comparison information to determine whether a flameout has occurred. The control arrangement is also capable of accommodating a response or delay time associated with the exhaust gas sensor.

Abstract: A rabbit for radiation formed of an aromatic polyester composed of ethylene-2,6-naphthalenedicarboxylate units as main recurring units and having an intrinsic viscosity of 0.45 to 0.90.

Abstract: A biaxially oriented film of polyethylene-2,6-naphthalate having a Young's modulus of at least 650 kg/mm.sup.2 in a given direction on the film plane and a direction crossing it at right angles, the difference between the Young's moduli in the two directions being at most 200 kg/mm.sup.2, the difference between the thermal shrinkages in the two directions being 0 to 0.1%.

Abstract: A magnetic recording flexible disc composed of a polyester film substrate having formed thereon a magnetic layer, the improvement wherein said polyester film is a biaxially oriented film consisting of poly-1,4-cyclohexylene dimethylene terephthalate wherein at least 90 mole % of a glycol component is 1,4-cyclohexanedimethanol and at least 80 mole % of an acid component is terephthalic acid, a maximum value of a temperature dependent expansion in the surface direction of the film is 9.times.10.sup.-6 to 35.times.10.sup.-6 /.degree.C., a maximum value of a humidity dependent expansion in the surface direction of the film is 0 to 8.0.times.10.sup.-6 /% RH, the difference between the maximum and minimum values of the temperature dependent expansion in the surface direction of the film is 0 to 8.0.times.10.sup.-6 /.degree.C., and the difference between the maximum and minimum values of the humidity dependent expansion in the surface direction of the film is 0 to 3.0.times.10.sup.-6 /% RH.