Abstract: A process for production of isobutylene by dehydration reaction of t-butyl alcohol or its aqueous solution is provided wherein the dehydration reaction is carried out in gaseous phase on fixed-bed type silica-alumina catalyst with adding non-reactive gas and/or water vapor to feed gas or reaction gas and/or with diluting at least a part of the catalyst with a carrier.

Abstract: An endoscope comprising as an image-transmitting member a multifilament type plastic optical fiber, an object lens arranged on one end of the optical fiber and a device for guiding an image of an object transmitted to the other end of the optical fiber to an image-receiving portion, wherein the multifilament type plastic optical fiber has an islands-in-sea structure in which 50 to 10,000 light-transmitting core-sheath structure islands having a diameter of 5 to 200 .mu. are arranged in the sea so that the same positional relationship of the islands is maintained on both ends of the optical fiber, and the core occupancy ratio in the total cross-section of the optical fiber is at least 50%.

Abstract: Disclosed is an antistatic thermoplastic resin composition which comprises a thermoplastic resin and a minor amount of an antistatic property-imparting material which is a polymer comprising 20 to 100 weight % of units of a monomer having a quaternary ammonium base represented by the formula (I): ##STR1## wherein R.sub.1 represents hydrogen or methyl, R.sub.2 through R.sub.4 represent hydrogen or (C1-9) alkyl, which may have a substituent, n is a number of 1 to 10, and X.sup.- represents a monovalent acid group or a corresponding equivalent of an acid, and up to 80 weight % of units of a copolymerizable vinyl or vinylidene monomer.

Abstract: A multifilament type plastic optical fiber having a substantially rectangular cross-section and an islands-in-the-sea structure in which 100 to 10,000 islands are arranged in the sea, wherein the respective islands have a substantially circular cross-section and a core-sheath structure, the islands are arranged in a sigzag-stacked structure, the core occupancy ratio in the multifilament type optical fiber cores section is at least 50% and the brightness index value I which is defined by the following (1), is at least 4.5.times.10.sup.-2 :I=S.multidot.NA.sup.2 .multidot.10.sup.-(.alpha.L/10) (1)wherein S stands for the core occupancy ratio in the multifilament type optical fiber, .alpha. stands for the transmission loss (db/m) per meter of the multifilament type optical fiber, NA stands for the numeral apertures, and L stands for the length (m) of the used optical fiber.

Abstract: A method and an apparatus for producing a slub yarn from a filament yarn, in which the starting yarn is propelled by an air stream at a first rate and made to impinge on a liquid (water) surface, whereby the yarn is opened to individual single filaments which entangle and fold with each other to form a thicker portion in the yarn body, while being held in a slack condition in the water and finally withdrawn therefrom at a second rate lower than the first rate. The water is preferably whirled to form a vortex. Interlacing of the yarn after withdrawal from the water is also preferable to strengthen the yarn structure.

Abstract: A cladding material for an optical fiber is described, which is made of a polymer comprised of (A) 10-90 wt. % of a long-chain fluoroalkyl group-containing monomer of the formula: ##STR1## wherein F is F, CH.sub.3 or CF.sub.3, and n is an integer from 5 to 11, (B) 5-90 wt. % of a short-chain fluoroalkyl group-containing monomer of the formula: ##STR2## wherein Y is as defined above, X is F, CH.sub.3 or CF.sub.3, and m is an integer of from 1 to 4, and (C) 0-50 wt. % of other copolymerizable monomer. The melt flow index indicating the amount in gram of the polymer extruded for 10 minutes from a nozzle with an orifice having an inner diameter of 2 mm and a length of 8 mm under the conditions of a temperature of 230.degree. C. and a load of 5 kg, is not larger than 30.

Abstract: Disclosed is an instrument for measuring living body components, which has (i) a fine tube having at one end thereof a connection portion to be connected to an indwelling needle or indwelling catheter and an infusion portion, from which at least a blood anticoagulant solution can be infused, (ii) a fine linear sensor for measuring living body components, extended from the inferior of the fine tube to the outside through the connection portion, and (iii) a mechanism for introducing blood at least into the interior of a fine tube portion of the indwelling needle or catheter intermittently or periodically when the indwelling needle or catheter is connected to the fine tube and kept in the blood vessel and then discharging blood into the blood vessel. A sensing portion of the sensor is located within the fine tube portion of the indwelling needle or catheter when the indwelling needle or catheter is connected to the connection portion of the fine tube.

Abstract: An optical fiber array comprising a great number of multifilament type plastic optical fibers having a substantially rectangular peripheral sectional shape and including 10 to 10000 light-transmitting islands having a diameter of 5 to 200 .mu.m, which are densely arranged in the sea, wherein one ends of the multifilament type plastic optical fibers are arranged in one line or a plurality of lines and the other ends thereof are integrated in a substantially rectangular or substantially circular shape.

Abstract: Disclosed is a process for producing methacrylic acid from methacrolein in high yields and at high selectivity which comprises vapor phase catalytic oxidation of methacrolein with molecular oxygen, characterized by using a catalyst represented by the formula: P.sub.a Mo.sub.b V.sub.c Cu.sub.d Zn.sub.e A.sub.f B.sub.g C.sub.h D.sub.i O.sub.

Abstract: Disclosed is an improved light transmitting fiber comprising a transparent inorganic substance or organic polymeric material as a core component and a methacrylate polymer as a cladding component. The methacrylate polymer is a methacrylimide-containing fluoroalkyl methacrylate polymer comprising (A) 2 to 98 weight % of methacrylimide units of formula (I): ##STR1## wherein R represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, (B) 98 to 2 weight % of structural units derived from a fluoroalkyl methacrylate monomer, and (C) 0 to 50 weight % of structural units derived from a monomer copolymerizable with the monomer (B).

Abstract: A porous water-treating material comprising cut porous strads each comprising a resinous matrix material which consists essentially of a thermoplastic polymer material or a mixture thereof with an inorganic particulate material. Each strand having a number of pores connected to each other and an irregularly rugged peripheral surface which has a ratio in diameter of a circumscribed circle to an inscribed circle in any cross-sectional profile from 1.10:1 to 5.00:1 and a ratio of the distance between circumscribed lines to that between inscribed lines in any side projection profile of from 1.10:1 to 3.00:1. The cut porous strands are prepared by melt-extruding a resinous mixture of the resinous matrix material with a blowing agent at a temperature higher than the melting point of the thermoplastic polymer material and the thermally decomposing point of the blowing material so as to cause the strands to have a number of pores and an irregularly rugged peripheral surface thereof.

Abstract: Acrylic resin sheets having an excellent heat moldability and solvent resistance are prepared by:(1) preparing a syrup of methyl methacrylate or a monomer mixture comprising at least 60 weight % of methyl methacrylate and not more than 40 weight % of an acrylic acid ester by partially polymerizing the monomer or monomers in the presence of 0.01 to 2.0 weight %, based on the monomer or monomers, of a chain transfer agent, as well as a polymerization initiator; and(2) incorporating the thus-prepared syrup with 0.02 to 1.0 weight %, based on the syrup, of a cross-linking agent, and subjecting the resulting mixture of cast polymerization under such conditions that if the crosslinking agent is not present, the intrinsic viscosity of the completely polymerized sheet is in the range of 0.05 to 0.12 l/g.

Abstract: Disclosed is an impact-resistant thermoplastic resin composition which comprises a graft copolymer [II]. The graft copolymer [II] is prepared by enlarging the particles in a latex of a rubbery copolymer [I] formed by emulsion polymerization of a monomer mixture of 51-91 wt. % of an alkyl acrylate and 49-1 wt. % of 1,3-butadiene to adjust the particle size to 0.12-0.4 .mu.m by addition of (A) an acid group-containing copolymer obtained by performing emulsion polymerization of a mixture of 3-40 wt. % of acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, cinnamic acid, sorbic acid and/or p-styrene-sulfonic acid, and 97-35 wt. % of an alkyl acrylate, and (B) a salt of an oxyacid having a central element of Groups III to VI of the periodic table, the element belonging to the second or third period, with an alkali or alkaline earth metal or Zn, Ni or Al; and then, polymerizing in the presence of the enlarged rubber copolymer a monomer or monomer mixture comprising 50-100 wt.

Abstract: Disclosed is a composition suitable for the preparation of a gasket for use in the production of shaped resin articles by cast polymerization. The composition is comprises (A) 100 weight parts of a vinyl chloride resin, (B) 30 to 70 weight parts of a carboxylic acid ester or phosphoric acid ester plasticizer, (C) 0.5 to 10 weight parts of an epoxy type plasticizer and (D) 0.1 to 5 weight parts of a barium- or zinc-containing stabilizer.

Abstract: A light diffusing device is disclosed for an edge lighted panel wherein the device includes a thin transparent light transmitting base plate, a light diffusing layer formed on a front surface of the base plate and a light reflection surface formed in the vicinity of the rear surface of the base plate. The base plate and the light diffusing layer are integrally bonded together through an intermediate layer formed between the base plate and the light diffusing layer.

Abstract: A multifilament type plastic optical fiber having a substantially uniform cross-section and an islands-in-sea structure, in which 10 to 10,000 islands are arranged in the sea, the respective islands have a substantially uniform cross-section having a diameter of 10 to 200.mu.

Abstract: Disclosed is an .alpha.-methylcinnamic acid ester derivative represented by the formula: ##STR1## wherein n is an integer of from 5 to 18, R.sub.1 represents an optically active group of the formula ##STR2## in which m is an integer of from 1 to 5 and *C represents an asymmetric carbon atom, and R.sub.2 represents ##STR3##The .alpha.-methylcinnamic acid ester derivative is valuable as a ferroelectric liquid crystal or an additive to a ferroelectric liquid crystal.

Abstract: Disclosed is an impact-resistant thermoplastic resin composition which comprises a graft copolymer [II]. The graft copolymer [II] is prepared by enlarging the particles in a latex of a rubbery copolymer [I] formed by emulsion polymerization of a monomer mixture of 51-91 wt. % of an alkyl acrylate and 49-1 wt. % of 1,3-butadiene to adjust the particle size to 0.12-0.4 .mu.m by addition of (A) an acid group-containing copolymer obtained by performing emulsion polymerization of a mixture of 3-40 wt. % of acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, cinnamic acid, sorbic acid and/or p-styrene-sulfonic acid, and 97-35 wt. % of an alkyl acrylate, and (B) a salt of an oxyacid having a central element of Groups III to VI of the periodic table, the element belonging to the second or third period, with an alkali or alkaline earth metal or Zn, Ni or Al; and then, polymerizing in the presence of the enlarged rubber copolymer a monomer or monomer mixture comprising 50-100 wt.

Abstract: A process for the preparation of a multifilament optical fiber having 1,000 to 10,000 islands as optical filaments, which comprises using a composite spinning spinneret for the preparation of an islands-in-a-sea type multifilament fiber, which comprises at least three piled orifice plates including an orifice plate having many island-forming nozzle holes, an orifice plate having a sea-forming nozzle hole and an orifice plate having a filament-gathering nozzle hole, the nozzle hole of the orifice plate arranged just above the lowermost orifice plate having a trumpet-shaped opening extending toward the lower end face thereof and a sea component flow passage being formed between two orifice plates arranged just above the lowermost orifice plate, and supplying a thermoplastic polymer for forming cores of optical filaments from the island-forming nozzle holes and a sea-forming thermoplastic polymer from the sea-forming nozzle hole to effect composite spinning and gathering many filaments in the gathering nozzle ho

Abstract: An impact resistant methacrylic resin composition having improved transparency, weatherability and impact resistance comprising a multi-layer graft copolymer and a methacrylic resin is disclosed.