Abstract: A biodegradable filament of polyglycolic acid resin having practical properties represented by high tensile strength and knot strength is produced. A polyglycolic acid resin having a residual monomer content of below 0.5 wt. % is melt-spun, quenched in a liquid bath of at most 10° C. and then stretched in a liquid bath of 60-83° C. to produce a polyglycolic acid resin filament having a tensile strength of at least 750 MPa and a knot strength of at least 600 MPa.

Abstract: There is provided a laminate sheet which is excellent in oxygen-barrier property and moisture resistance, biodegradable as a whole and therefore suitable as a base material for packaging materials, such as food containers. The laminate sheet is formed by laminating a water-containable and biodegradable polymer substrate sheet or a precursor thereof in a water-containing state with a layer of polyglycolic acid resin having a residual monomer content below 0.5 wt. % to form a laminate, and subjecting the laminate to bonding and forming under heat and pressure.

Abstract: A polyglycolic acid resin-based multilayer sheet, comprising: a plant substrate sheet and a biodegradable resin layer laminated by melt-adhesion onto the plant substrate sheet, wherein said biodegradable resin layer comprises one or plural layer including at least a polyglycolic acid resin layer, and the multilayer sheet includes on the substrate sheet a melt-adhesion layer comprising a biodegradable resin exhibiting a melt viscosity of 10-5.0×103 Pa·sec as measured at a temperature of 240° C. and a shear speed of 122 sec?1 and having a melting point of at most 235° C. The multilayer sheet has a laminate structure composed of biodegradable materials exerting little load to the environment at the time of disposable thereof and yet is excellent in oxygen-barrier property and moisture resistance, thus being suitable as a food container-forming material.

Abstract: A biodegradable filament of polyglycolic acid resin having practical properties represented by high tensile strength and knot strength is produced. A polyglycolic acid resin having a residual monomer content of below 0.5 wt. % is melt-spun, quenched in a liquid bath of at most 10° C. and then stretched in a liquid bath of 60-83° C. to produce a polyglycolic acid resin filament having a tensile strength of at least 750 MPa and a knot strength of at least 600 MPa.

Abstract: There is provided a laminate sheet which is excellent in oxygen-barrier property and moisture resistance, biodegradable as a whole and therefore suitable as a base material for packaging materials, such as food containers. The laminate sheet is formed by laminating a water-containable and biodegradable polymer substrate sheet or a precursor thereof in a water-containing state with a layer of polyglycolic acid resin having a residual monomer content below 0.5 wt. % to form a laminate, and subjecting the laminate to bonding and forming under heat and pressure.

Abstract: A gas barrier film, comprising a mixture-deposited layer made of a metal and a metal oxide, provided on at least one surface of a polymer film substrate, and characterized in that, where the integration values of the XPS spectrums of the metal and the metal oxide of the above mixture-deposited layer are defined as SMe and SMeO, respectively, the value of the integration value ratio (SMeO/SMe) in the above mixture-deposited layer is 1.5 to 100, and that a resin layer formed using a polycarboxylate-based solution is laminated on at least one surface of the mixture-deposited layer.

Abstract: A multilayer sheet made of a polyglycolic acid resin which is constructed by the fusion/lamination of a biodegradable resin layer on a base sheet of vegetable origin, characterized in that the biodegradable resin layer comprises one or more layers involving at least one polyglycolic acid resin layer and the layer fused with the base sheet is made of a biodegradable resin having a melt viscosity of 10 to 5.0×103 Pa·sec at a temperature of 240° C. and a shear speed of 122 sec?1 and a melting point of 235° C. or lower. Although the multilayer sheet has a lamination structure made of biodegradable materials with light environmental burden at disposal, it is excellent in oxygen-barrier properties and resistance to moisture transmission. Thus, it is appropriately usable as a food container material.

Abstract: A biodegradable filament of polyglycolic acid resin having practical properties represented by high tensile strength and knot strength is produced. A polyglycolic acid resin having a residual monomer content of below 0.5 wt. % is melt-spun, quenched in a liquid bath of at most 10 ° C. and then stretched in a liquid bath of 60-83 ° C. to produce a polyglycolic acid resin filament having a tensile strength of at least 750 MPa and a knot strength of at least 600 MPa.

Abstract: A heat-resistant stretched film is obtained by stretching a resin composition comprising 100 parts by weight of a poly(arylene sulfide) of a substantially linear structure and 5 to less than 100 parts by weight of a melt-stable poly(arylene thioether-ketone). The poly(arylene sulfide) has a melt viscosity of at least 1,000 poises as measured at 310.degree. C. and a shear rate of 200 sec.sup.-1. The poly(arylene thioether-ketone) has predominant recurring units of the formula ##STR1## wherein the --CO-- and --S-- groups are bonded in the para position to each other through the benzene ring, and has the following physical properties (a)-(c):(a) a melting point, Tm being 310.degree.-380.degree. C.;(b) a melt crystallization temperature, Tmc (420.degree. C./10 min) being at least 210.degree. C. and a residual melt crystallization enthalpy, .DELTA.Hmc (420.degree. C./10 min) being at least 10 J/g; and(c) a reduced viscosity being 0.3-2 dl/g at 25.degree. C. and a polymer concentration of 0.

Abstract: Disclosed herein is a heat-resistant film obtained by biaxially-stretching a composition which comprises (A) 50-90 parts by weight of a polyetheretherketone having predominant recurring units of the formula: ##STR1## and (B) 50-10 parts by weight of a substantially linear poly(arylene sulfide) having melt viscosity of at least 1,000 poises. A production process of such a heat-resistant film is also disclosed, which comprises biaxially stretching the above composition in a temperature range at least equal to the crystallization temperature (Tc) of the poly(arylene sulfide) but not higher than the crystallization temperature (Tc) of the polyetheretherketone.

Abstract: A poly(arylene sulfide) sheet excellent in planarity and smoothness is formed of a composition composed at least principally of a substantially linear, high molecular poly(arylene sulfide) having a melt viscosity of at least 1,000 poises. It has an elongation at break of at least 10% at 23.degree. C. and a Young's modulus of at least 5 kg/mm.sup.2 at 200.degree. C., and per area of 1 cm.times.2 cm on at least one of its surfaces, contains not more than 1 convex or concave whose angle of elevation or depression is at least 2.degree. and whose height or depth is at least 10 .mu.m. The sheet is produced by melting the composition, extruding the melt through a slit die, cooling and solidifying the extrudate into a sheet, preheating the sheet for 3-100 seconds in a temperature range of from a temperature 20.degree. C. lower than the glass transition temperature of the polymer to a temperature 25.degree. C.

Abstract: A poly(arylene sulfide) sheet excellent in planarity and smoothness is formed of a poly(arylene sulfide) having a melt viscosity, .eta..sup.* of 1,000-25,000 poises as measured at 310.degree. C. and a shear rate of 200 sec.sup.-1, and a melt crystallization temperature, Tc.sub.2 of 170.degree.-240.degree. C., wherein Tc.sub.2 is an exothermic peak temperature of crystallization which appears upon the measurement by a differential scanning calorimeter at a cooling rate of 10.degree. C./min after the polymer is heated from 23.degree. to 380.degree. C. at a rate of 10.degree. C./min and then held for 3 minutes at 380.degree. C. It has a surface roughness, Ra of 0.09 .mu.m or less on at least one side thereof and a degree of crystallization of at least 5%. Its number of flexings to break, Y satisfies the following equation (I):log Y.gtoreq.7.11-2.34 log t (I)wherein t means a thickness (.mu.m) of the sheet.

Abstract: Disclosed herein is a heat-resistant film obtained by biaxially-stretching a composition which comprises (A) 50-90 parts by weight of a polyetheretherketone having predominant recurring units of the formula: ##STR1## and (B) 50-10 parts by weight of a substantially linear poly(arylene sulfide) having melt viscosity of at least 1,000 poises. A production process of such a heat-resistant film is also disclosed, which comprises biaxially stretching the above composition in a temperature range at least equal to the crystallization temperature (Tc) of the poly(arylene sulfide) but not higher than the crystallization temperature (Tc) of the polyetheretherketone.

Abstract: A poly(arylene sulfide) sheet excellent in planarity and smoothness is formed of a poly(arylene sulfide) having a melt viscosity, .eta.* of 1,000-25,000 poises as measured at 310.degree. C. and a shear rate of 200 sec.sup.-1, and a melt crystallization temperature, Tc.sub.2 or 170.degree.-240.degree. C., wherein Tc.sub.2 is an exothermic peak temperature of crystallization which appears upon the measurement by a differential scanning calorimeter at a cooling rate of 10.degree. C./min after the polymer is heated from 23.degree. C. to 380.degree. C. at a rate of 10.degree. C./min and then held for 3 minutes at 380.degree. C. It has a surface roughness, Ra of 0.09 .mu.m or less on at least one side thereof and a degree of crystallization of at least 5%. Its number of flexings to break, Y satisfies the following equation (I):log Y.gtoreq.7.11-2.34log t (I)wherein t means a thickness (.mu.m) of the sheet.

Abstract: A biaxially-stretched film is made of a resin composition composed of 100 parts by weight of a substantially linear poly(arylene sulfide) having a melt viscosity of at least 1,000 poises and 2-25 parts by weight of a styrene-based resin. The film is produced by diluting a master batch, which has been prepared in advance and is composed of the poly(arylene sulfide) and styrene-based resin, with an additional supply of the poly(arylene sulfide) so as to prepare a resin composition containing the polystyrene-based resin in an amount of 2-25 parts by weight per 100 parts by weight of the poly(arylene sulfide), and then biaxially stretching the thus-prepared resin composition.

Abstract: A poly(arylene sulfide) sheet excellent in planarity and smoothness is formed of a composition composed at least principally of a substantially linear, high molecular poly(arylene sulfide) having a melt viscosity of at least 1,000 poises. It has an elongation at break of at least 10% at 23.degree. C. and a Young's modulus of at least 5 kg/mm.sup.2 at 200.degree. C., and per area of 1 cm.times.2 cm on at least one of its surfaces, contains not more than 1 convexity or concavity whose angle of elevation or depression is at least 2.degree. and whose height or depth is at least 10 .mu.m. The sheet is produced by melting the composition, extruding the melt through a slit die, cooling and solidifying the extrudate into a sheet, preheating the sheet for 3-100 seconds in a temperature range of from a temperature 20.degree. C. lower than the glass transition temperature of the polymer to a temperature 25.degree. C.

Abstract: A biaxially-stretched film is made of a resin composition composed of 100 parts by weight of a substantially linear poly(arylene sulfide) having a melt viscosity of at least 1,000 poises and 0.5-80 parts by weight of a styrene-based resin. The film is produced by diluting a master batch, which has been prepared in advance and is composed of the poly(arylene sulfide) and styrene-based resin, with an additional supply of the poly(arylene sulfide) so as to prepare a resin composition containing the polystyrene-based resin in an amount of 0.5-80 parts by weight per 100 parts by weight of the poly(arylene sulfide), and then biaxially stretching the thus-prepared resin composition.