Abstract: A polymer piezoelectric film comprising a poled film of a vinylidene fluoride copolymer having a high molecular weight as defined by an inherent viscosity within a specific range comprising 40 to 90 mol. % of vinylidene fluoride and 10 to 60 mol. % of trifluoroethylene. Such a high molecular weight vinylidene fluoride copolymer can give a preferable state of molecular arrangement during film formation, particularly preferably formation by casting, to provide a film excellent in piezoelectric characteristic and secondary processing characteristic.

Abstract: Disclosed herein are an integrated carbon article of a large size having a bulk density of more than 1.01 g/cm.sup.3, comprising pieces of carbonaceous material(s) of the same or different quality and flexible graphite sheet(s) produced by interposing the flexible graphite sheet(s) between each of the pieces of carbonaceous material(s), bonding each of the pieces of carbonaceous material(s) and the flexible graphite sheet(s) with an adhesive agent and calcining the thus bonded material at a temperature of not lower than 800.degree. C.

Abstract: A resin-made optical fiber is composed of a core of a polymer or copolymer obtained from a polymerizable monomer, which contains at least 1 wt. % of a crosslinkable monomer, and a cladding of a polymer of copolymer having a refractive index smaller than the core. The optical fiber is fabricated by filling a polymerizable monomer into a hollow fiber like cladding material, which is adapted to form a cladding and is made of a polymer or copolymer, and then placing the resultant composite material under polymerizing conditions to polymerize the polymerizable monomer. The latter step may preferably be carried out by causing the composite material to travel continuously in the direction of its length into a polymerization zone where conditions for the polymerization of the polymerizable monomer are satisfied, whereby the polymerizable monomer is successively polymerized to form a core having a refractive index greater than the cladding.

Abstract: A flexible carbon material is produced by carbonizing a composite material comprising carbon fibers having an average length of 6 to 50 mm and a binding agent. Carbon lumps are derived from the binding agent and are dispersed in a matrix of the carbon fibers so as to restrain a plurality of the carbon fibers while yet permitting relative slippage to occur as between the carbon fibers and carbon lumps such that the carbon fiber material exhibits a flexibility ratio D/d of not greater than 200 (where D is the diameter of curvature of the carbon material, when bent, just before breakage, and d is the thickness of the carbon material). The carbon fibers and lumps are preferrably present in an amount of from 5 to 50%, and 5 to 70% by volume, respectively, based upon the total volume of the carbon material.

Abstract: A photochromic lens is composed of a lens member made of a lens resin; and a photochromic layer applied on at least one side of the lens member and formed of a resin of a three-dimensional network structure. The layer-forming resin contains a spirooxazine compound represented by the following general formula (I): ##STR1## wherein R.sub.1 means a hydrogen or halogen atom or a cyano, C.sub.1-6 alkyl or C.sub.1-6 alkoxy group, and R.sub.2 denotes a C.sub.1-6 alkyl group, --CH.sub.2).sub.n COOH, --CH.sub.2).sub.n CN, substituted arylalkyl group or --CH.sub.2).sub.n COOR in which R is a C.sub.1-6 alkyl group and n stands for an integer of 1-4. The layer-forming resin may additionally contain a phenol resin and/or a phenolic compound. A hard coat layer may optionally be applied on the surface of the photochromic layer.

Abstract: A vinylidene fluoride resin film having (1) a crystal melting point of 182.degree. C. or higher as measured by differential scanning calorimeter in nitrogen atmosphere at a temperature elevation speed of 10.degree. C./min; (2) a diffraction point corresponding to (1 1 .zeta.) of the .alpha.-phase crystal in the wide angle X-ray diffraction photograph; and (3) an orientation degree of the crystal of 0.85 or more when measured under irradiation of X-ray incident vertically on a major surface of the film. The vinylidene fluoride resin film is obtained by inflation accompanying melt necking stretching. The film has improved mechanical properties and heat-stability and is also adapted for use as a base film of a metallized film.

Abstract: A halogen-containing resin lens material, having a refractive index of n.sub.D =1.55 or higher, an Abbe number of 27 or higher and good dyeable property and comprising a copolymer containing 10 to 90 wt. % of a monomer (I) represented by the formula (I) shown below: ##STR1## wherein: R.sup.1 represents hydrogen or CH.sub.3 group; X.sup.1 a halogen atom except for fluorin; and p the number of substituted halogens which is an integer selected from 1 to 5, and n is an integer selected from 1 to 4, R.sup.1 existing in plural number and being either identical or different, X.sup.1 when existing in plural number being either identical or different and 10 to 70 wt. % of a crosslinking monomer having two or more polymerizable functional groups (the percentages being based on the copolymer weight).

Abstract: A dielectric film is a stretched body of a composition comprising a thermoplastic resin cross-linked to have a gel content of about 10 to about 75%, and finely divided dielectric porcelain particles dispersed in the thermoplastic resin. Stretching does not result in a decrease in the dielectric constant of the film and provides a great electrostatic capacitance. The dielectric film is manufactured by a method comprising the steps of cross-linking the thermoplastic resin of the composition containing the dielectric porcelain particles as well, and stretching the composition at a predetermined temperature selected in association with the thermoplastic resin.

Abstract: Vinylidene fluoride polymer films are provided having improved dielectric constants and tan .delta. values and which do not exhibit substantial shrinkage when heated to temperatures below the crystalline melt point. Processes for preparation of such films are presented.

Abstract: Disclosed herein is a thin transparent polytetrafluoroethylene film having:(1) a film thickness of 0.1-100 .mu.m;(2) a parallel light transmittance of at least 70% (as measured in accordance with JIS K 7105); and(3) a tensile strength of at least 1 kg/mm.sup.2 (as measured in accordance with JIS K 6887 except for the use of a pulling speed of 10 mm/min.).The film is produced by fluorinating with a fluorine gas a thin film formed from a solution of a fluoroethylene polymer having an inherent viscosity of at least 2.5 dl/g (as measured at a temperature of 30.degree. C. and a solution concentration of 0.4 g/dl) in accordance with the casting process and having a thickness of 0.1-100 .mu.m.

Abstract: Compositions each comprising a copolymer of a specific allylic or (meth)acrylic compound of an iodine-substituted benzoic acid derivative and a comonomer have a refractive index n.sub.D.sup.20 of at least 1.58 and an Abbe's number of at least 28 and are excellent starting materials for the production of high quality lenses.

Abstract: Ultrafine fiber of an ethylene tetrafluoride copolymer having an orientation degree (.pi.) of at least 0.6 and an average fineness of 0.0001 to 0.9 denier. A process for producing such fiber or a porous membrane thereof is also disclosed.

Abstract: A transparent film of a vinylidene fluoride copolymer, comprising a dry film of a vinylidene fluoride copolymer having a parallel light transmittance of 85% or higher at a film thickness of 30 microns. The transparent film is obtained by forming a mixture of a vinylidene fluoride copolymer having a specifically high molecular weight with a solvent into a film, preferably by casting, and evaporating off the solvent.

Abstract: A vinylidene fluoride resin having an inherent viscosity of 0.8 to 1.4 dl/g in dimethylformamide is melt-extruded and cooled and solidified under draft-stretching to form a film having a birefringence of 25.times.10.sup.-3 or larger. The film is heat-treated at 80.degree.-120.degree. C. and split into a split yarn. The split yarn has a Young's modulus even higher than that of the polypropylene split yarn and, when provided with a surface charge above the glass transition temperature, retains the charge semi-permanently. The charged split yarn is particularly suitable for forming a gas filter.

Abstract: A lens material having a refractive index n.sub.D.sup.20 of at least 1.57 or more and an Abbe's number .nu. of at least 30, comprising: a copolymer comprising (I) 10 to 85% by weight of a halogen-containing monomer represented by the following formula (1), (II) 15 to 90% by weight of a halogen-containing monomer represented by the following formula (2), and (III) 0 to 20% by weight of a monomer copolymerizable with the above mentioned monomers, the composition of the copolymer being based on the total quantity of the monomers (I), (II), and (III): ##STR1## wherein: D represents ##STR2## in which n represents an integer selected from the group consisting of 0, 1, and 2; each R.sup.1 represents hydrogen or a methyl group; Y represents CHOH; and r represents 0 or 1; each of X.sup.1 and X.sup.

Abstract: Disclosed herein are a porous substrate capable of adsorbing protein, having an exclusive molecular weight of at least 30,000, comprising a cross-linked copolymer having methylol groups, the copolymer being made of a monomer of styrenes and a cross-linking agent copolymerizable with the monomer, the outer surface of the porous substrate being hydrophilic and the pore surface thereof being hydrophobic, and a process for producing the same.

Abstract: A vinylidene fluoride resin fiber having an increased tensile strength is obtained by spinning by melt-extrusion of a vinylidene fluoride resin having a large polymerization degree under the conditions of a small extrusion rate and a large draft ratio into a small diameter of spun fiber. The thus obtained fiber is characterized by having no crystal melting point based on the vinylidene fluoride chains at a temperature below 178.degree. C., and having a mean crystal length in the molecular chain direction of 200 A or longer and a birefringence of 30.times.10.sup.-3 or larger.

Abstract: The photoresist material comprises a polymer having chloromethyl groups introduced therein and containing 2-isopropenylnaphthalene as one component, an average substitution degree of the chloromethyl groups based on the polymer is within a range of 0.2 to 5.The photoresist material has a high glass transition point, a high sensitivity to radiation and an excellent dry etching resistance, whereby it is suitably used for the manufacture of a semiconductor element using radiation and provides a good resolution on etching.

Abstract: A substrate for liquid chromatography comprising a spherical particle of highly cross-linked polymer which is produced from (a) 100 parts by weight of a monomer of vinyl ester, acrylate or methacrylate, these esters having a long alkyl chain, if desired, together with a comonomer copolymerizable with the monomer and (b) 10 to 80 parts by weight of a cross-linking agent copolymerizable with the monomer and having at least two functional groups, and a process for isolating and purifying a fat-soluble substance, for instance, a lower alkyl ester of eicosapentaenoic acid or docosahexaenoic acid by means of the liquid chromatography on the substrate.

Abstract: A mixture of water-soluble substances, particularly a mixture of proteins, a mixture of enzymes or a mixture of water-soluble vitamins, is fractionated by subjecting an aqueous solution of said mixture of water-soluble substances to gel chromatography through a filter bed of a cross-linked gel copolymer of vinylpyrrolidone and a cross-linking agent having a triazine ring system of the formula (I) or (II): ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are the same or different and each radical is selected from the group consisting of --CH.sub.2 --CH.dbd.CH.sub.2, --CH.sub.2 --C.tbd.CH and --CH.sub.2 --C(CH).sub.2, in a diluent.