Abstract: A process and an apparatus for producing terephthalic acid economically by oxidizing paraxylene supplied to an oxidizing reactor connected with a compactly designed distillation column in an acetic acid-based solvent, while effecting the distillatory recovery of the paraxylene and acetic acid efficiently without suffering from stuffing of the distillation column.

Abstract: A circuit board for mounting one or more optical devices such as light receiving LSI chips and light emitting LSI chips. The circuit board has a flexible transparent substrate, a window portion which is formed as a slit-like transparent region of the transparent substrate, a plurality of electrodes for bonding the optical devices thereon provided on one surface of the substrate, a plurality of aggregated electrodes provided on the other surface on a region corresponding to the electrodes in a manner extending respectively in the longitudinal direction of the window portion and electrical connection portions penetrating the substrate. Each of the aggregated electrodes is electrically connected with two or more of the electrodes through the electrical connection portion. The circuit board will be used in, for example, an optical reader, an optical printer or the like in such a manner that the light which is coming in and/or going out of the optical device is transmitted through the window portion.

Abstract: A process for preparing a novel superabsorbent polymer which is readily hydrolyzed and conform to environment by reacting a polysuccinimide with a diamine in an aqueous solution or an organic solvent to partially crosslink the polysuccinimide, and subsequently or concurrently hydrolyzing the remaining imide ring with an alkali while controlling the pH; and the superabsorbent polymer thus obtained.

Abstract: The present invention provides an ethylene/.alpha.-olefin copolymer comprising constituent units (a) derived from ethylene and constituent units (b) derived from an .alpha.-olefin having 3 to 20 carbon atoms, the ethylene copolymer being characterized in that(A) the ethylene/.alpha.-olefin copolymer has a density (d) of 0.88 to 0.95 g/cm.sup.3 ;(B) the ethylene/.alpha.-olefin copolymer has a MFR of 0.01 to 200 g/10 min as measured at a temperature of 190.degree. C. and a load of 2.16 kg;(C) the temperature (Tm) at which the exothermic curve of the ethylene/.alpha.-olefin copolymer measured by a differential scanning calorimeter (DSC) shows the highest peak and the density (d) satisfy the relationTm<400d-250;(D) the quantity fraction (W) of a n-decane-soluble component at room temperature satisfy the relation,in the case of MFR.ltoreq.10 g/10 min.,W<80.times.exp (-100(d-0.88))+0.1in the case of MFR.gtoreq.10 g/10 min.,W<80.times.(MFR-9).sup.0.35 .times.exp (-100(d-0.88))+0.

Abstract: In one aspect, the present invention relates to polyimides having excellent thermal resistance and process for preparing the same comprising carrying out condensation of 4,4'-bis(3-aminophenoxy)biphenyl with pyromellitic dianhydride in the presence of a different diamine compound and optionally with a different tetracarboxylic acid dianhydride.In a second aspect, the present invention relates to a heat resistant resin composition consisting essentially of an aromatic polyetherimide and a defined polyimide.In a third aspect, the present invention relates to a polyimide resin composition comprised on a defined polyimide and a separate high-temperature engineering polymer.In a fourth aspect, the present invention relates to a resin composition comprised of a defined polyimide and an aromatic polyamideimide.

Abstract: A moldable polyimide resin composition which has melt-flowability and excellent processability in addition to essential heat-resistant of polyimide and comprises an aromatic bisimide compound and polyimide resin. A further aspect relates to a carbon fiber reinforced polyimide resin composition which has excellent mechanical strengths and comprises a carbon fiber coated with aromatic bisimide compound on the surface and the polyimide resin. A still further aspect relates to a novel bisimide compound which is very useful as the aromatic bisimide compound in the composition.

Abstract: A process for isomerization of an endo-form of aromatic group-containing norbornenes represented by the following formula (I) to an exo-form which comprises bringing the endo-form into contact with a solid acid catalyst. ##STR1## wherein p is 0 or an integer of 1 or more, q and r are each 0, 1 or 2, R.sup.1 to R.sup.15 are each independently hydrogen or halogen atom, aliphatic hydrocarbon group, aromatic hydrocarbon group or alkoxy group, R.sup.5 (or R.sup.6) are R.sup.9 (or R.sup.7) may be linked together through an alkylene group of 1-3 carbons or may be directly linked together.

Abstract: A holding container which is made of a polyether ether ketone resin and is suitable for use in holding one or more substrates upon fabrication of the corresponding number of thin-film semiconductor substrates useful in driving a planar display, for example, a liquid crystal display.

Abstract: The present invention relates to a solid catalyst composed of a specific solid catalyst component [A-1], the catalyst containing the solid catalyst and the olefin polymerization process using the solid catalyst, in which the solid catalyst component [A-1] comprises; (a-1) a particulate carrier composed of a specific oxide of a metal; (a-2) an organoaluminum oxy compound; and (a-3) a specific transition metal compound containing a specific ligand, wherein the organoaluminum oxy compound (a-2) and the transition metal compound (a-3) are supported on the particulate carrier (a-1).The catalysts are applicable to a suspension polymerization and a vapor phase polymerization, and capable of preparing spherical olefin polymers excellent in particle characteristics at high polymerization activity.

Abstract: There are provided an optical disk substrate formatted according to the zone formatted system, method for initialization thereof, and driving apparatus for initialization of the optical disk. The optical disk substrate is initialized while at least one track in the vicinity of the inner peripheral side and/or the outer peripheral side in the radial direction of the boundary between an optional zone and another zone situated on the outer peripheral side is left unused as a recording area. By virtue of this construction, at least one of the tracks having a high possibility of bringing about the pit shift or double transfer is left unused as a recording area. Accordingly, the information stored in a recording area can be read out without being influenced by the occurrence of the pit shift or double transfer, and thus it is possible to get rid of the occurrence of a burst error caused by such pit shift or double transfer.

Abstract: A polymerizable monomer has the formula, ##STR1## where R.sub.5 and R.sub.6 are similar or dissimilar and are selected from group consisting of hydrogen and methyl, k is an integer of 2-10, and the isopropenyl substituent on the aromatic ring is in the p-position or m-position.The polymerizable monomer can be used to prepare a high hardness transparent resin which in turn can be used to prepare a laminated transparent plastic material.

Abstract: The ethylene/.alpha.-olefin/diene rubber composition of the present invention is a specific ethylene/.alpha.-olefin/diene rubber composition comprising a high-molecular ethylene/.alpha.-olefin/diene copolymer rubber (A) having a specific molecular weight distribution, a specific intrinsic viscosity [.eta.] and a specific iodine value, and a low-molecular liquid ethylene/.alpha.-olefin copolymer (B) having a specific intrinsic viscosity [.eta.]. This ethylene/.alpha.-olefin/diene rubber composition of the invention is excellent in both the processability (flowability) and the shape retention properties in the vulcanization molding process, and the rubber composition can provide a vulcanized rubber molded product which is excellent in surface smoothness, mechanical strength, low-compression permanent strain properties, resistance to abrasion and resistance to dynamic fatigue.

Abstract: A diphenylamine with both the phenyl groups being substituted is prepared by reacting a phenol with ammonia in the presence of a hydrogen transfer catalyst and a cyclohexanone; or by converting a portion of the phenol to the cyclohexanone in the presence of a hydrogen transfer catalyst and under hydrogen pressure and then reacting the remaining portion of the phenol with ammonia in the presence of the cyclohexanone so converted and the hydrogen transfer catalyst. The diphenylamine can be obtained very efficiently.

Abstract: The invention discloses a CD-WO type optical recording medium which has a constitution obtained by successively laminating a recording layer, a metal reflection layer and a protective layer; is prepared by using in the recording layer a colorant having a melting point of 150.degree. to 300.degree. C., decomposition initiating temperature of 200.degree. to 350.degree. C., and .lambda. max of 720 nm; and has high sensitivity, low recording distortion and high durability. The colorant can be enhanced its effect by introducing halogen atoms.

Abstract: A topsheet for use in body fluid absorptive articles is so improved that collapse and clogging of liquid passages therein may be reliably avoided. The topsheet includes an upper sheet, provided with skin-contacting areas and liquid passages, and a lower sheet provided with skin-non-contacting areas, areas welded to the liquid passages, and exposed areas. The exposed areas are welded to each of the liquid passages around lower openings thereof so as to protect the liquid passage against collapse and clogging. The exposed areas define a skin-contacting surface which rises up into each of the liquid passages without extending above the upper surface of the skin-contacting areas. The upper sheet cooperates with the lower sheet to define cavities extending in the direction of the topsheet thickness.

Abstract: A transparent panel heater which can be used for heating a window portion of liquid crystal displays, refrigerated showcases, freezer showcases, defrosters of windshields, and the like. The panel heater has a transparent substrate, a transparent conductive film formed on the substrate, a substantially light-transmittable metallic thin layer formed on the conductive film and a pair of electrodes for electrifying the conductive film. The metallic thin layer is preferably deposited by a dry process such as a sputtering process, an ion plating method, various CVD methods, and the like. The electrodes are preferably formed on the metallic thin layer by a wet plating method.

Abstract: Foams comprising innumerable cells dispersed in thermoplastic polymer compositions substantially consisting of polylactic acid or a copolymer of lactic acid and hydroxycarboxylic acid and having degradable characteristics in the natural environment.The foams can be used for containers such as food trays and throw away cups comprising molded sheet foam of a thermoplastic and degradable polymer or heat insulating materials and cushioning materials comprising bulk foam.

Abstract: A color-developing composition comprises a multi-valent-metal-modified salicylic acid resin (Resin A) and a polycondensation resin (resin B) at a weight ratio of 90-30 to 10-70. Resin A is composed of 5-35 mole % of a structural unit (I) and 65-95 mole % of at least one structural unit (II) or 65-95 mole % of a coupled structural unit of at least one unit (II) and at least one unit (III) and has a weight-average molecular weight of 350-5,000. Resin B is composed of the unit (II) and/or the unit (III) and has a weight-average molecular weight of 350-5,000. ##STR1## wherein Z represents M/m, M being a metal ion of m valence and m being an integer; R.sub.1 and R.sub.2 represent H or a C.sub.1-12 alkyl, aralkyl, aryl or cycloalkyl group; R.sub.3 and R.sub.6 represent H or a C.sub.1-4 alkyl group; and R.sub.4 and R.sub.5 represent H or CH.sub.3.

Abstract: Information recording discs comprise a disc substrate having a recording layer on one side thereof, one hub having an insertion portion to be inserted into a center hole of the disc substrate and a flange portion to cover the disc substrate in the vicinity of the center hole, at least an apex of the insertion portion being composed of a magnetic material, the hub being inserted into the center hole so that the flange portion is positioned on the recording layer side of the disc substrate, and an adhesive layer is provided between the flange portion and the disc substrate. By this construction, a portion of the hub which protrudes from the back surface of the disc substrate, facing toward the spindle of a turn table can be altered in dimension and/or the diameter of the protrusion portion of the hub can be made smaller than that of the center hole of the disc substrate.

Abstract: Near-infrared absorbers which contain phthalocyanine derivatives in which the four benzene rings contained in the molecule independently have 1 to 4 substituents are light and thermal resistant and possess high molar extinction coefficients. Such near-infrared absorbers are useful in optical recording media, near-infrared absorption filters, and liquid crystal display devices.