Abstract: A chain includes a plurality of link assemblies connected with each other. One of the adjacent link assemblies has a first pair of plates disposed apart in the direction perpendicular to the longitudinal direction of the chain and a pair of hollow cylindrical bushes press-fitted to the first pair of plates. The other of the adjacent link assemblies has a second pair of plates disposed apart in the direction perpendicular to the longitudinal direction of the chain so as to locate at the outside of the first pair of plates and a pin penetrated through the bush and press-fitted to the second pair of plates. A moisture absorption member which retains lubricant oil between the bush and the pin is placed between facing surfaces of the first and second plates. The moisture absorption member has a large deformation amount and a small restoration amount.

Abstract: Rubber-containing graft copolymer particles having excellent powder properties are prepared by mixing, with 100 parts by weight (as solid content) of a slurry of a rubber-containing graft copolymer (A), 0.1 to 10 parts by weight (as solid content) of a rigid non-elastic polymer (B) having a glass transition temperature of 40.degree. C. or higher and a weight-average molecular weight of 10,000 to 500,000 in a substantially slurry state.

Abstract: A polyvinyl chloride resin composition comprising (i) 100 parts by weight of a polyvinyl chloride resin and (ii) 2 to 40 parts by weight of a multi-stage copolymer obtained by polymerizing resin component formable monomers in the range of from more than 30 parts by weight to 50 parts by weight in three stages onto 50-70 parts by weight of a butadiene elastomer having a glass transition temperature ranging from -40.degree. C. to 5.degree. C. obtained by a copolymerization of a monomer mixture of 70 to 90% by weight of butadiene, 10 to 30 percent by weight of an aromatic vinyl monomer and a polyfunctional monomer added in an amount corresponding to 3 to 10 parts by weight per 100 parts by weight of the total amount of the butadiene and aromatic vinyl monomer.

Abstract: Rubber-containing graft copolymer particles excellent in powder properties are prepared by a process comprising mixing, with 100 parts by weight (as solid content) of rubber-containing graft copolymer (A) in a state of slurry, 0.1 to 10 parts by weight of a rigid non-elastic multi-stage polymer (B), in a state of slurry, consisting of 30 to 80% by weight of a (co)polymer component comprising 40 to 100% by weight of methyl methacrylate and 0 to 60% by weight of one or more other monomers copolymerizable therewith being polymerized at least in the first stage and 5 to 70% by weight of a (co)polymer component comprising 70 to 100% by weight of methyl methacrylate and 0 to 30% by weight of one or more other monomers copolymerizable therewith being polymerized in the final stage, the total amount of the (co)polymer components in the respective stages being 100% by weight and the content of polymeric units derived from an acrylic ester in the multi-stage polymer (B) being from 5 to 30% by weight.

Abstract: A frictional transmission chain drive for use between V-groove pulleys comprises a series of C-shaped chain struts and friction force struts superposed along the length of an endless transmission chain. The chain struts are fitted in grooves located across link plates of the chain, with their open ends alternately located on opposite sides of the transmission chain. The friction force struts are provided with recesses which grip the chain to prevent sideways movement of the struts relative to the chain. The friction force struts on opposite sides of a chain strut can have their open ends on the same said of the chain as the open end of the chain strut, or, alternatively, can have their open ends on the side of the chain opposite the side on which the open end of the chain strut is located.

Abstract: Noise reduction in a silent chain is achieved by forming the majority of the toothed link plates with modified tooth profiles having a circular concave portion conforming t the shape of the teeth of the sprocket engaged by the chain, and a circular convex portion near the tip, the center of curvature of the convex portion being on the dedendum side of the pitch line. Additional link plates having a different meshing pitch are disposed at irregular intervals along the length of the chain. These additional link plates can have linear of modified tooth profiles.

Abstract: A silent chain having a series of links, with adjacent links being pivotally joined by transversely-extending connecting pins. Each link is defined by a plurality of link plates disposed in sidewardly adjacent relationship, which link plates define inwardly projecting sprocket teeth adjacent opposite ends thereof. Guide plates are disposed adjacent opposite sides of some of the links and extend between adjacent connecting pins. Plate spring links are sidewardly interposed between adjacent link plates or between a link plate and a sidewardly adjacent guide plate. The spring link plates have a configuration such that no portion thereof extends into the pitch circle of the sprocket which meshes with the chain links.

Abstract: An improved chain comprising inner link plates, sintered oil-retaining bushings secured to the inner link plates, outer link plates, connecting pins secured to the outer link plates and the pins being rotatable within the bushings, the improvement comprising: the sintering density of the bushings being in the range of approximately 6.0 g/cm.sup.3 to 7.1 g/cm.sup.3 ; and, a roller rotatably supported on each bushing.

Abstract: A core-clad plastic optical fiber is described, comprising a polyglutarimide series polymer having a polymeric structural unit represented by formula (I) ##STR1## wherein R represents a hydrogen atom, an alkyl group, a cycloalkyl group, or an aromatic group and n represents a positive integer,having a thermal deformation temperture of at least 120.degree. C. as a core, and an organic polymer having a refractive index lower than the refractive index of the core as a clad layer, said plastic optical fiber having the characteristic that the light transmission loss measured at 655 nm is not more than 500 dB/km.

Abstract: A reinforced resin composition which comprises 50-95% by weight of polyglutarimide resin and 5-50% by weight of carbon fibers.The polyglutarimide resin is one containing imide units of 2% by weight or more, represented by the formula, ##STR1## wherein R stands for hydrogen atom or an aliphatic, aromatic or alicyclic hydrocarbon group having 1 to 20 carbon atom(s).

Abstract: Methacrylimide-containing polymers are continuously produced by introducing 10 to 60 wt. % of an inert solvent, 90 to 40 wt. % of methacrylic acid, a methacrylic acid ester or a monomer mixture comprising at least 50 wt. % of methacrylic acid or a methacrylic acid ester, and a radical polymerization initiator and a molecular weight modifier into a polymerization reaction zone, converting at least 80 wt. % of the charged monomer to a polymer at 60.degree.-170.degree. C., adding a compound represented by the formula:R--NH.sub.2wherein R represents a hydrogen atom, an alkyl group having 1-12 carbon atoms, a cycloalkyl group having 7-11 carbon atoms or an aryl group having 6-10 carbon atoms,to the polymerization reaction liquid, carrying out reaction of the resulting mixture at 150.degree. to 300.degree. C. in an imidization reaction zone, and finally separating volatile substances from the reaction fluid.

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 methacrylate resin composition comprising a methacrylate resin containing methacrylimide units of the following formula: ##STR1## wherein R is a hydrogen atom or an aliphatic, alicyclic or aromatic hydrocarbon group having from 1 to 20 carbon atoms, and having a yellowness index (YIs) of at most 3 as measured in the form of a solution of the heated resin composition and a total light transmittance of from 89 to 95%.

Abstract: A heat-resistant resin molded article excellent in abrasion resistance, surface smoothness, solvent resistance, durability and adhesiveness between base material and cured film, consisting of (1) a resin molded article composed of 2% by weight or more of a structural unit represented by the following structural formula ##STR1## (wherein R is a hydrogen atom, an alkyl group, an aryl group or an alicyclic group of 1 to 20 carbon atoms) and 98% by weight or less of an ethylenic monomer unit and (2) a cured film formed on the surface of said resin molded article by curing a crosslinking-curable resin material containing 30% by weight or more of at least one monomer having three or more (meth)acryloyloxy groups in one molecule, as well as a process for producing said heat-resistant resin molded article.

Abstract: A plastic light-transmitting fiber having a core-sheath structure. A polymer having methacrylimide or N-substituted methacrylimide units is used for the core component. A polymer having a refractive index smaller by at least 1% than that of the polymer of the core component is used for the sheath component. The heat resistance of the light-transmitting fiber is highly improved.

Abstract: A heat-resistant resin molded article excellent in abrasion resistance, surface smoothness, solvent resistance, durability and adhesiveness between base material and cured film, consisting of (1) a resin molded article composed of 2% by weight or more of a structural unit represented by the following structural formula ##STR1## (wherein R is a hydrogen atom, an alkyl group, an aryl group or an alicyclic group of 1 to 20 carbon atoms) and 98% by weight or less of an ethylenic monomer unit and (2) a cured film formed on the surface of said resin molded article by curing a crosslinking-curable resin material containing 30% by weight or more of at least one monomer having three or more (meth)acryloyloxy groups in one molecule, as well as a process for producing said heat-resistant resin molded article.