Abstract: A means for controlling the temperature of a warming material includes an air-permeable film or the like. The warming material includes the temperature control means and a heating composition. The temperature control means for controlling the heating temperature of the warming material includes one or more aliphatic compounds that have a melting point of 35-65° C. and a solubility in water (g/100 mL) at 20° C. of 5 or less.

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: 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: 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.

Abstract: Provided is a film for retaining freshness of vegetables and fruits which comprises a synthetic resin film, a microporous resin film and a water-absorbing layer interposed between both said films, said microporous resin film having a maximum pore diameter not larger than 30 microns and a moisture permeability not lower than 100 g/m.sup.2 /24 hr.

Abstract: A process for producing porous films which comprises blending 100 parts by weight of a polyolefin resin with 50 to 500 parts by weight of barium sulfate preferably having an average particle diameter of 0.1 to 7 .mu.m, melting the resulting resin composition and forming it into a film, and then stretching the film at least uniaxially by a factor of 1.5 to 7.

Abstract: A process for producing porous films which comprises melting a resin composition consisting essentially of (1) 100 parts by weight of a high-pressure-processed low-density polyethylene resin having a melt index of 0.5 to 7 and a density of 0.915 to 0.935, a linear low-density polyethylene resin having a melt index of 0.5 to 8.5 and a density of 0.915 to 0.935, or a mixture thereof and (2) 50 to 500 parts by weight of barium sulfate having an average particle diameter of 0.1 to 7 .mu.m; forming the molten resin composition into a film; and then stretching the film at least uniaxially by a factor of 1.5 to 7. As the linear low-density polyethylene resin, a copolymer of ethylene and hexene and/or octene is particularly preferred.

Abstract: A combustion furnace or reactor with a multi-stage fluidized bed system wherein upper and lower fluidized bed formation zones in which the fluidized beds of bed particles containing particles of lime stone are separated through a partition device. The partition device is provided with a plurality of exhaust gas distribution holes for distributing the exhaust gases produced in the lower fluidized bed into the upper fluidized bed and a plurality of nozzles through which issue the combustion air and/or recirculated exhaust gases into the upper fluidized bed. Combustion products such as NO.sub.x and SO.sub.x are desulfurized and denitrified respectively within the reactor by calcium compounds which absorb SO.sub.2 and act as catalysts for reducing NO.sub.x.

Abstract: An improvement of a swirl type fuel atomizer is disclosed in which a plurality of projections, grooves or recesses are equiangularly formed around an opening of a single-nozzle hole so that the liquid fuel injected may be divided into a plurality of fuel spray patterns. The complete combustion with a relatively low temperature may be ensured so that the emission of nitrogen oxides may be substantially eliminated or reduced.

Abstract: An improvement of a swirl type fuel atomizer is disclosed in which a plurality of notches are equiangularly formed around an opening of a single-nozzle hole so that the liquid fuel injected may be divided into a plurality of fuel spray patterns. The complete combustion with a relatively low temperature may be ensured so that the emission of nitrogen oxides may be substantially eliminated or reduced.