Abstract: A foaming thermoplastic polyurethane resin is a reaction product of a polyisocyanate component containing a bis(isocyanatomethyl)cyclohexane and a polyol component. In a peak of chromatogram obtained by measurement of the foaming thermoplastic polyurethane resin with gel permeation chromatography, the area of a high molecular weight component having a weight average molecular weight of 400,000 or more with respect to the total area of the peak is 25% or more and 60% or less.

Abstract: A foaming thermoplastic polyurethane resin is a reaction product of a polyisocyanate component containing a bis(isocyanatomethyl)cyclohexane and a polyol component. In a peak of chromatogram obtained by measurement of the foaming thermoplastic polyurethane resin with gel permeation chromatography, the area of a high molecular weight component having a weight average molecular weight of 400,000 or more with respect to the total area of the peak is 25% or more and 60% or less.

Abstract: In an optical compensation film, when a direction that gives the maximum in-plane refractive index is X axis, an in-plane direction perpendicular to X axis is Y axis, a film thickness direction is Z axis, refractive indexes at the wavelength of 590 nm in each axis direction are nX, nY, and nZ respectively, and the film thickness is d, an in-plane retardation value defined as R=(nX?nY)·d and a thickness direction retardation value defined as Rth=|(nX+nY)/2?nZ|·d, both of which are measured under conditions at 23 degrees centigrade and a relative humidity of 50%, satisfy the inequalities of Rth/R?5 and R?9.5 (nm).

Abstract: A method of providing surface protection during cutting using treatment with a chemical solution or dicing with defined requirements.

Abstract: In an optical compensation film when a direction wherein a refractive index within a film surface is maximum is an X axis, a direction vertical to the X axis within the surface is a Y axis, and a film thickness direction is a Z axis, and refractive indexes at 590 nm in each axis direction are nX, nY, nZ, and a film thickness is d, a retardation value within the surface expressed as R=(nX?nY)?d, which is measured under conditions at 23° C. and a relative humidity of 50%, and a thickness direction retardation value expressed as Rth=|(nX+nY)/2?nZ|·d satisfy inequalities of Rth/R?5 and R?9.5 (nm).

Abstract: An adhesive material and a pressure sensitive adhesive film containing the same of the present invention are characterized in that they satisfy the following requirements (a) and (b). These adhesive material and pressure sensitive adhesive film of the present invention exhibit excellent stability against not only light and heat but also various chemicals. Consequently, they are suitable applications in surface protection uses, transport storage uses, heating treatment uses, grinding/polishing uses, cutting processing uses and transport/storage uses in the fields of electronic/semiconductor materials, optical/display materials and the like, where demands for performances and qualities are strict. The above requirements are: (a) an olefinic polymer is contained, and (b) by measurement according to a differential scanning calorimetry test, the melting temperature Tm is in the range of 80° C. to 180° C. and the heat of fusion ?H is at least 1 J/g.

Abstract: The object of the invention is to provide an adhesive sheet suitable for applications to surface protection involving cutting processing, and in particular an adhesive sheet suitable for applications to surface protection requiring excellent cutting processability, chemical solution treatment and dicing, particularly in the fields of electronic circuit material, semiconductor material and optical material demanding high performance and qualities, are not detrimental to the environment. An adhesive sheet 10 having an adhesive layer 2 laminated on at least one side of a substrate layer 1, wherein the substrate layer 1 contains an olefin polymer, and has a tensile modulus of elasticity and tear strength in a specific range.

Abstract: The stretched film of the lactic acid-based polymer of the invention can degrade under natural environment, and additionally has an excellent mechanical strength and durability. By use of a lubricant in combination with an inorganic filler, these properties are further improved and thickness accuracy is enhanced. Consequently, the stretched film of the lactic acid-based polymer of the invention can be widely applied to a prepaid card and other various film materials, lamination materials and packaging materials. Even though abandoned after use in the natural environment, the stretched film relatively quickly decomposes into carbon dioxide and water and does not accumulate as waste.

Abstract: Polyimide filaments and polyimide films having great strength, high elastic modulus and high crystallinity and comprising a novel polyimide which can be melt-processed without impairing high crystallinity and which essentially consists of recurring structural units represented by the formula (I): ##STR1## more than 85 mol % the polyimide consists of recurring structural units of the formula (II): ##STR2## and from 0.5 to 15 mol % of the polyimide consists of recurring structural units represented by the formula (III), the formula (II) exclusive, the formula (IV) and/or the formula (V).

Abstract: A polyimide film essentially consisting of polyimide having recurring units of the formula (I): ##STR1## which has a density of 1.335 to 1.390 g/cm.sup.3 at 23.degree. C. and/or a refractive index of 1.605 to 1.680 at 23.degree. C. in the direction of thickness and is transparent; and a preparation process of the polyimide film by extruding the polyimide having recurring units of the above formula (I) through a common melt-extrusion process, casting in a chill-roller to obtain an unstretched film, uniaxially or biaxially stretching the unstretched film to cause molecular orientation, and successively setting the stretched film through heat-treatment.

Abstract: A method for preparing a biaxially stretched polyether ether ketone (PEEK) film having excellent precision in thickness, insulating properties and heat shrinkage from an amorphous PEEK film which includes a first stretching step of roll-stretching the amorphous PEEK film in a temperature range of from 50.degree. C. to (Tg-10).degree. C. in a stretching ratio of from 150% to 350% in the progress direction of the film while a necking phenomenon is caused in the film; a second stretching step of stretching the film in the temperature range of from Tg to 170.degree. C. in a direction at right angles to the stretching direction in the first stretching step in a stretching ratio of from 150% to 350%; and a heat set step of thermally setting the stretched film at two stages in the temperature range of 210.degree.-330.degree. C. and the temperature range of 180.degree.-210.degree. C.

Abstract: Polyimide sheets having excellent thermal resistance and good surface appearance of the resultant sheets are obtained by a melt-extrusion process from a specific polyimide in the temperature range of 300.degree. C. to 450.degree. C. and a moisture content of 200 ppm or less.

Abstract: An insulated wire having excellent thermal resistance and good surface appearance is obtained by coating a condutor with a specific polyimide in a temperature range of 300.degree. C. to 450.degree. C. and controlling moisture content to 200 ppm or less.

Abstract: Polyimide which is obtained by polymerization and consists essentially of recurring structural units of the formula (I): ##STR1## wherein X is a single bond or a hexafluoroisopropylidene group, is processed to a form of pellet, followed by heat-treating to obtain crystallinity of 5% or more, and fed to an extruder to obtain articles.

Abstract: A process for the preparation of a polyimide molded form comprising the steps of swelling a primary-molded form consisting essentially of polyimide having recurring units of the formula (I) ##STR1## by using an aprotic polar solvent and subsequently stretching the swelled form.

Abstract: Polyimide which is obtained by polymerization and consists essentially of recurring structural units of the formula (I): ##STR1## wherein X is a single bond or a hexafluoroisopropylidene group, is processed to a form of pellet, followed by heat-treating to obtain crystallinity of 5% or more, and fed to an extruder to obtain articles.

Abstract: In the preparation of a film by melt-extrusion process of thermoplastic polyimide, static charge is applied to a molten film, primary cooling is carried out by adhering the film to a cooling roller having a surface temperature in the range of from the glass transition temperature of said polyimide -50.degree. C. to the glass transition temperature -15.degree. C., the film is successively cooled to 60.degree. C. and less without bringing the film into contact with rollers, and is taken up under tension to give a polyimide film.