Abstract: A filter material comprises a cellulose acetate fiber tow containing 5-50% by weight of a water soluble material and/or a water dispersible material which are soluble in a solvent which dissolves cellulose acetate and which are not compatible with cellulose acetate. Due to the inclusion of the above-mentioned water soluble material and/or water dispersible material in the cellulose acetate fiber, in the presence of moisture, the fiber surface becomes porous by the elution of this water soluble material and/or water dispersible material from the fiber, and the surface area of the fiber is increased. Consequently, the shape of the cellulose acetate fiber tow is easily broken down, and the decomposability of the fiber by microorganisms and the like is increased. When a cigarette filter is made using this type of filter material, a cigarette filter is obtained which has easy decomposability in the natural environment and particularly in water, in atmospheres which contain large amounts of moisture, and the like.

Abstract: The present invention relates to an acrylonitrile copolymer comprising 70% by weight or more of an acrylonitrile monomer unit and 0.1-30% by weight of a fluoroalkyl methacrylate or fluoroalkyl acrylate monomer unit and having an intrinsic viscosity of 0.8-10, as well as to an acrylonitrile type core-sheath conjugate fiber using the above copolymer as the sheath component. The copolymer according to the present invention has water repellency by itself; accordingly, the above conjugate fiber prepared therefrom also exhibits water repellency permanently.

Abstract: Disclosed is a cladding composition suitable for a plastic clad silica or glass core optical fiber of a good light transmittance. The cladding composition comprises (A) a fluorinated monofunctional acrylate or .alpha.-fluoroacrylate composition, (B) a polyfunctional acrylate or .alpha.-fluoroacrylate having at least two acryloyl or .alpha.-fluoroacryloyl radicals in the molecule, (C) a photoinitiator, and if desired, (D) a stabilizer selected from thiodicarboxylic acid diesters and hindered phenols. The fluorinated monofunctional acrylate or .alpha.-fluoroacrylate comprises 1-60 weight % of a highly fluorinated acrylate or .alpha.-fluoroacrylate of the formula: ##STR1## wherein Y is H or F, X is H or F, l is 1 to 12 and n is 5 to 12, and 40-99 weight % of a lowly fluorinated acrylate or .alpha.-fluoroacrylate of the formula: ##STR2## wherein X and Y are as defined above, and m is 1 to 3.

Abstract: The present invention relates to an acrylonitrile copolymer comprising 70% by weight or more of an acrylonitrile monomer unit and 0.1-30% by weight of a fluoroalkyl methacrylate or fluoroalkyl acrylate monomer unit and having an intrinsic viscosity of 0.8-10, as well as to an acrylonitrile type core-sheath conjugate fiber using the above copolymer as the sheath component. The copolymer according to the present invention has water repellency by itself; accordingly, the above conjugate fiber prepared therefrom also exhibits water repellency permanently.

Abstract: Disclosed is a polymer composition comprising (I) 60 to 99.8 wt. % of an amorphous copolymer comprising (a) units derived from perfluoro-2,2-dimethyl-1,3-dioxole and (b) units derived from at least one ethylenically unsaturated monomer selected from ethylene, tetrafluoroethylene, chlorotrifluoroethylene, and CF.sub.2 .dbd.CFOCF.sub.3, and (II) 0.2 to 40 wt. % of a compound having a hydrocarbon group containing at least one fluorine atom and at least one functional group selected from --OH, --SR, --COOH, --SO--, --SO.sub.2 --, --CONH--, --COO--CO--, --CONHCO--, --COO--, --CN, --NCO, --CO--, --HCOO--, --NH.sub.2 --, --NH--, .dbd.N, --SO.sub.3 H, --NHNH.sub.2, --CONH.sub.2, --CH.dbd.CH.sub.2, --CH.dbd.CH--, (RO).sub.n X.sub.3-n Si--, wherein R is a C.sub.1-5 alkyl group, n is a number of 0 to 3, and X is halogen or a C.sub.1-5 alkyl group. The polymer composition is useful for a plastic cladding of an optical fiber.

Abstract: Disclosed is a resin composition comprising a copolymer [I] having a number average molecular weight of at least 15,000, which comprises at least 30 mole % of the following recurring units [A]: ##STR1## and a compound [II] having a number average molecular weight of at least 1,000, which is comprised of perfluoroalkylether recurring units [D]. This resin composition is used as a cladding of a core-clad optical fiber.

Abstract: A heat-resistant plastic optical fiber having a concentric three-layered structure comprising a core layer, a sheath layer and a protective layer, wherein the polymer constituting the sheath layer is a copolymer comprising 30 to 80 mole % of a fluorodioxole represented by the general formula: ##STR1## wherein R and R' are each a fluorine atom or a trifluoromethyl group, and 70 to 20 mole % of at least one other comonomer. Also, a process for the production of the heat-resistant plastic optical fiber comprising spinning a core-forming polymer, a sheath-forming polymer and a protective layer-forming polymer by a three-layered conjugate spinning process.

Abstract: Disclosed is a polymer composition comprising (I) 60 to 99.8 wt. % of an amorphous copolymer comprising (a) units derived from perfluoro-2,2-dimethyl-1,3-dioxole and (b) units derived from at least one ethylenically unsaturated monomer selected from ethylene, tetrafluoroethylene, chlorotrifluoroethylene, and CF.sub.2 =CFOCF.sub.3, and (II) 0.2 to 40 wt. % of a compound having a hydrocarbon group containing at least one fluorine atom and at least one functional group selected from --OH, --SR, --COOH, --SO--, --SO.sub.2 --, --CONH--, --COO--CO--, --CONHCO--, --COO--, --CN, --NCO, --CO--, --HCOO--, --NH.sub.2 --, --NH--, .dbd.N, --SO.sub.3 H, --NHNH.sub.2, --CONH.sub.2, --CH.dbd.CH.sub.2, --CH.dbd.CH--, (RO).sub.n X.sub.3-n Si--, wherein R is a C.sub.1-5 alkyl group, n is a number of 0 to 3, and X is halogen or a C.sub.1-5 alkyl group. The polymer composition is useful for a plastic cladding of an optical fiber.

Abstract: A plastic optical fiber comprising a core polymer having a refractive index of n.sub.1, which comprises a polymer of .alpha., .beta.-unsaturated carboxylic acid fluoroalkylester represented by the general formula [I] as the main monomer, and a clad copolymer having a refractive index of n.sub.2, which comprises perfluoro(2,2-dimethyl-1,3-dioxole) as the main monomer, and which satisfies the relationship of (n.sub.1 -n.sub.2 .gtoreq.0.01): ##STR1## wherein X represents CH.sub.3, H, D, F, Cl, or CF.sub.3, Y represents H or D, and Rf represents a fluoroalkyl group having a linear or branched chain. The optical fiber is prepared by a melt-extrusion method. The optical fiber has excellent light transmitting properties, and it is suitable as an optical fiber for long distance light communication.

Abstract: Disclosed is a resin composition comprising a copolymer [I] having a number average molecular weight of at least 15,000, which comprises at least 30 mole % of the following recurring units [A]: ##STR1## and a compound [II] having a number average molecular weight of at least 1,000, which is comprised of perfluoroalkylether recurring units [D]. This resin composition is used as a cladding of a core-clad optical fiber.

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: A plastic core-plastic cladding optical fiber is described wherein the core is composed of a copolymer of a perfluorodioxole represented by the following formula: ##STR1## wherein R and R' independently represent F or CF.sub.3, with at least one other ethylenically unsaturated monomer substantially free of CH bonds and the copolymer has no first order transition temperature as determined by the differential scanning colorimetry (DSC) and has a second order transition temperature not lower than 100.degree. C. as determined by DSC.

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 a non-rigid vinyl chloride polymer composition comprising 100 weight parts of a vinyl chloride polymer resin, 5-50 weight parts of a graft copolymer modifier and 10-300 weight parts of a plasticizer. The graft copolymer modifier is obtained by graft-polymerizing 25-150 weight parts of an alkyl ester of methacrylic acid having 1 to 4 carbon atoms in the alkyl group or a monomer mixture composed of at least more than 50% by weight of said alkyl ester of methacrylic acid onto 100 weight parts of an acrylic elastomer having a swelling degree of 5 to 25 so that the grafting ratio is not larger than 50%. The acrylic elastomer is obtained by polymerizing a mixture comprising an alkyl ester of acrylic acid having 2 to 10 carbon atoms in the alkyl group or a monomer mixture composed of at least 50% by weight of said alkyl ester of acrylic acid, and a polyfunctional crosslinking agent.