Abstract: Disclosed is a process for the preparation of a modified methacrylic resin molding material, wherein a volatile component is removed from a methacrylic polymer composition containing a volatile component including an unreacted monomer, a solvent or a by-product, and a modifying polymer is added to the methacrylic polymer composition to prepare a modified molding material.

Abstract: An optically active compound having a .delta.-valerolactone ring which is a ferroelectric liquid crystal and is represented by the following general formula (I): ##STR1## wherein m is an integer of from 1 to 8, Z is a group represented by the following formula: ##STR2## in which each of l and k is a number of 1 or 2 and l and k satisfy the requirement of 2.ltoreq.(l+k).ltoreq.3,X stands for a direct bond, ##STR3## Y stands for ##STR4## and A.sub.1 and A.sub.2 independently stand for --H, --F or --Cl, ##STR5## R stands for ##STR6## in which n is an integer of from 1 to 18, and * indicates the asymmetric carbon atom.

Abstract: Disclosed is a process for preparing a membranous gas separator comprising (a) a porous substrate having an average pore diameter of not greater than 100 .ANG. and (b) a .pi.-electron conjugated conducting polymer retained within at least a part of the pores of the porous substrate in such a way that the pores are not blocked, characterized in that retaining the .pi.-electron conjugated conducting polymer within the pore is carried out by a chemical oxidative polymerization.

Abstract: Disclosed is a modifier to be incorporated in a polyvinyl chloride resin, which is a graft copolymer obtained by carrying out, in the presence of 100 parts by weight of a butadiene rubber having a swelling degree of 10 to 50 and an average particle diameter of 0.1 to 0.4 .mu.m, first-stage graft polymerization of 1 of 42 parts by weight of methyl methacrylate and 0 to 5 parts by weight of an alkyl acrylate, second-stage graft polymerziation of 10 to 120 parts by weight of styrene and third-stage graft polymerization of 7 to 75 parts by weight to methyl methacrylate and 0 to 20 parts by weight of an alkyl acrylate, the content of the butadiene rubber in the graft copolymer being 35 to 75% by weight. The polyvinyl chloride resin composition having this modifier incorporated therein provides a molded article having excellent impact resistance, solvent resistance, and transparency.

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 zigzag-stacked structure, the core occupaney 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 : ##EQU1## 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: An illumination panel, which comprises an optical fiber sheet formed by arranging a plurality of optical fibers having a core-sheath structure, which has one end optically connected to a light source and a light-leaking portion on at least one surface thereof, a surface panel arranged on the front surface side of the optical fiber sheet, and a reflecting layer arranged on the back surface side of the optical fiber sheet, wherein the light-leaking portion is formed of a plurality of flaws extending to the core of the optical fiber from the sheath thereof, the light-leaking width of the light-leaking portion increases toward the side far from the light source from the side near to the light source, the presence density of the flaws increases toward the side far from the light source from the side near to the light source, and the depth of the flaws increases toward the side far from the light source from the side near to the light source, whereby the entire illumination surface is uniformly illuminated.

Abstract: A methacrylimide group-containing polymer having good optical characteristics, especially a resistance to coloration under heating and above to retain good light-transmitting characteristics for a long time even at a high temperature, is prepared by polymerizing methacrylic acid, a methacrylic acid ester, or a monomer mixture predominantly comprised of methacrylic acid or an ester thereof in the absence of a mercaptan chain transfer agent, and then imidizing the thus-prepared polymer. The resulting polymer is useful as the core component of a light-transmitting fiber having a core-sheath structure.

Abstract: Disclosed is a cladding composition for a plastic clad plastic core optical fiber, which comprises (a) an ultraviolet ray-curable monofunctional acrylic or .alpha.-fluoroacrylic monomer, (b) a polyfunctional acrylate or .alpha.-fluoroacrylate having at least two acryloyl or .alpha.-fluoroacryloy radicals in the molecule and (c) a photoinitiator. The difference (n.sub.1 -n.sub.2) between the refractive index n.sub.1 of the plastic core and the refractive index n.sub.2 of a cured product of the cladding composition is at least 0.01. The plastic clad plastic core optical fiber inhibits an enhanced heat resistance.

Abstract: In a spindle of a machine tool, a cylindrical member of the spindle adapted to accommodate the shank of a tool is prepared by winding carbon or glass fiber and the wound fiber is impregnated with a heat curable resin. After curing the resin a protective coating layer is applied to the other surface of the cylindrical member.

Abstract: A lens sheet comprising a transparent substrate and a lens portion composed of a cured product of an ultraviolet-curable resin composition, which is formed on at least one surface of the transparent substrate. The resin composition exhibits a polymerization shrinkage at curing of not larger than 20% as calculated based on the difference of the specific gravity at 25.degree. C., and a modulus of elasticity at 25.degree. C. after curing of 10 to 1,000 kg/cm.sup.2. The ultraviolet-curable resin composition is preferably comprised of a polyvalent (meth)acrylate, a mono(meth)acrylate and a photopolymerization initiator.

Abstract: A thermoplastic methacrylimide group-containing resin composition comprised of (a) a methacrylimide group-containing polymer comprising 5 to 100% by weight of units of an imide ring structure represented by the following structural formula (I): ##STR1## wherein R.sub.1 stands for a hydrogen atom, a substituted or unsubstituted alkyl, cycloalkyl, aryl, alkaryl, aralkyl or allyl group having 1 to 20 carbon atoms,and 0 to 95% by weight of units derived from at least one monoethylenically unsaturated monomer, and (b) a small amount of a tetramethylpiperidine derivative is described. A shaped article made from this composition has a highly improved weatherability.

Abstract: A digital PLL circuit to output a clock signal phase-synchronized with an input signal comprises a divider outputting the clock signal and a signal initiation pulse generator generating a signal to set the divider to a predetermined state depending on the input signal initiation. The maximum lead-in time is reduced to 1/n in comparison with prior art, and therefore the circuit is very suitable for use in the receiving part of a device which receives a burst data signal.

Abstract: An impact modifier for a thermoplastic resin is disclosed, which comprises (I) 100 parts by weight of a graft copolymer formed by graft-polymerizing (B) a monomer having a vinyl group in the molecule onto (A) a butadiene polymer and, incorporated therein, (II) 0.01 to 5 parts by weight of a thioether type heat stabilizer, (III) 0.01 to 5 parts by weight of a phosphite type heat stabilizer and (IV) 0.01 to 5 parts by weight of a phenol type heat stabilizer having a molecular eight of at least 500. A thermoplastic resin composition having this impact modifier incorporated therein exhibits a good heat discoloration resistance and heat deterioration resistance under high-temperature conditions, as well as an improved impact resistance.

Abstract: A visible light ray-curable monomeric composition for fastening loose teeth, comprising: a filler component consisting of fine, solid particles having an average size of 0.01 to 100 .mu.m and in an amount of 40% to 85% based on the weight of the total weight of the composition; a polyfunctional monomer component consisting of a radical-polymerizable, polyfunctional monomer; a monofunctional monomer consisting of a radical-polymerizable, monofunctional monomer; and a photopolymerization initiator; having a viscosity of 1,000 to 500,000 cps at a temperature of 25.degree. C., and contained in a light-shielded container.

Abstract: Disclosed is a thermoplastic resin composition comprising (A) a graft copolymer obtained by emulsion-graft-polymerizing 0 to 20% by weight of an acrylic monomer and 0 to 60% by weight of an aromatic vinyl monomer in the presence of 40 to 80% by weight (as solids) of a diene type rubber polymer latex containing at least 50% by weight of a diene type rubber polymer having a weight average particle diameter of at least 0.3 .mu.m, and (B) a copolymer of an .alpha.,.beta.-unsaturated cyclic anhydride and an aromatic vinyl compound. The thermoplastic resin composition has a high heat resistance and impact resistance.

Abstract: An actinic ray curable composition for casting polymerization which comprises:(A) 40-90 parts by weight of an urethane poly(meth)acrylate having at least two (meth)acryloyl groups in one molecule,(B) 10-60 parts by weight of a radical polymerizable vinyl monomer having a boiling point of 100.degree. C. or higher, and(C) 0.005-5 parts by weight, per 100 parts by weight of total of the above components (A) and (B), of at least one member selected from methylphenyl glyoxylate, 2-hydroxy-2-methyl-1-phenylpropane-1-one, hydroxycyclohexyl phenyl ketone and a photo-initiator represented by the general formula (I): ##STR1## (wherein R.sub.1 and R.sub.2 which may be identical or different each represents a phenyl group, a methoxy group, an ethoxy group or an isopropyloxy group) and a casting polymerization molded product obtained by radical polymerization of said composition by irradiation with actinic ray.

Abstract: The gas phase catalytic oxidation of an unsaturated aldehyde with molecular oxygen at 200.degree. to 500.degree. C. to give the corresponding unsaturated carboxylic acid is conducted in the presence of a catalyst represented by the following formula:Mo.sub.12 P.sub.a X.sub.b Y.sub.c Z.sub.d O.sub.ewherein the subscripts represent the atomic ratios of each component and a is 0.5 to 6, b is 0.001 to 6, c is 0.2 to 6, d is 0 to 6, and e is a value determined by the valencies of the elements present in the catalyst; and Mo is molybdenum, P is phosphorus, O is oxygen, X is at least one metal selected from the group consisting of rhodium, cerium and zirconium, Y is at least one alkali metal selected from the group consisting of potassium, rubidium and cesium, and Z is at least one metal selected from the group consisting of iron, cobalt, nickel, zinc, antimony, silicon, bismuth, cadmium, uranium, manganese, copper, vanadium, niobium and tantalum.

Abstract: A highly crystalline polyethylene terephthalate resin composition comprising (A) 100 parts by weight of a polyethylene terephthalate copolymer comprising ethylene terephthalate units as the main recurring units, which is formed by copolymerizing a glycol component containing 1 to 20% by weight of a polyalkylene glycol having an average molecular weight of 500 to 20,000 and 1.2 to 15% by weight of diethylene glycol with a carboxylic acid component composed mainly of terephthalic acid, (B) 5 to 200 parts by weight of a fibrous reinforcer, (C) 0.5 to 130 parts by weight of a nucleating agent, and (D) 0.1 to 60 parts by weight of a crystallization-promoting agent. The resin composition optionally contains 2 to 100 parts by weight of an inorganic compound, 2 to 100 parts by weight of an impact strength improver, 2 to 40 parts by weight of a flame retardant, or 1 to 20 parts by weight of a flame retardant assistant.

Abstract: Disclosed is a crosslinked polyester for a toner, which has an acid value of 5 to 20 mgKOH/g, a flow index of 0.1.times.10.sup.-4 to 300.times.10.sup.-4 ml/sec and a softening point lower than 145.degree. C., the polyester being formed by mixing a dicarboxylic acid component, a diol component and at least one crosslinking component selected from a polyfunctional carboxylic acid component having a trivalency or a higher valency and a polyhydric alcohol component having a trivalency or a higher valency at a mixing ratio represented by the following formula (1), reacting the mixture at a reaction ratio represented by the following formula (2) and subjecting the esterification product to polycondensation and crosslinking.0.8.ltoreq.R.ltoreq.1+5a (1)0.7.ltoreq.P.ltoreq.[R/(1+a)].sup.

Abstract: A sheet-shaped photoconductor composed of a plurality of optical fibers is prepared by melt-spinning a spinning dope into optical fibers and, before the as-spun fibers are completely solidified, bonding the fibers to one another along the entire length thereof. The melt-spinning is carried out using a nozzle having a plurality of annularly arranged orifices. The as-spun fibers are arranged linearly in parallel to but not in contact with one another by using a grooved guide, and then the optical fibers are brought into contact with and fusion-bonded to one another by using a fusion bonding guide having a concave curved face in the central portion thereof, and the thus-formed sheet-shaped photoconductor is taken up.