Abstract: The invention provides a heat-sensitive recording medium comprising (a) a support and (b) a heat-sensitive recording layer formed on the support and comprising a colorless or pale-colored basic dye and a color developing material capable of causing color development upon contact with the dye by heating, which medium is characterized in that the heat-sensitive recording layer contains at least one phosphate compound selected from the group consisting of 2,2'-methylenebis(4,6-di-tert-butylphenyl) phosphate of the general formula (1) shown below and alkali metal, ammonium and polyvalent metal salts thereof: ##STR1## wherein R represents a tert-butyl group.

Abstract: A slipping clutch having opposed driving and driven members, and a friction plate disposed therebetween such that a slipping torque may be obtained between the driving and driven members. The friction plate is made of fiber of high strength, and the member which slips relative to the friction plate is made of engineering plastics. In a preferred embodiment, a friction plate of high strength fiber is frictionally engaged on axially opposite sides of the driven member, which member is made of engineering plastics.

Abstract: A tripping torque setting mechanism of an overload clutch having an adjusting nut threadedly engageable with a thread provided on a cylindrical part of a clutch hub, the adjusting nut being tightened against a spring to produce an urging force corresponding to a predetermined tripping torque. A helical line having a pitch coinciding with the pitch of said thread and indicia for indicating the angular positions is provided on one of the adjusting nut or a member which does not rotate relative to the nut, and an indicator is provided on the other. The axially adjacent portions of the helical line are indicated by different colors and the indicia for indicating the angular positions are indicated by the same color as the portion of the helical line to which the indicia correspond.

Abstract: Disclosed is an electrostatic recording medium comprising an electroconductive support and as formed thereon a dielectric layer containing an insulating resin and a pigment, said dielectric layer carrying a surface static charge of a polarity opposite to that of a charge to be applied for image formation.

Abstract: Disclosed is an electrostatic recording medium comprising an electroconductive support and a dielectric layer formed on the electroconductive support and containing an insulating resin and a pigment, characterized in that the pigment comprises kaolin having a quartz content of not more than 2% by weight and that the dielectric layer has, on the surface thereof, projections based on the pigment and having an equivalent diameter of 5-15 um as spacers.

Abstract: A leathery sheet material which comprises a fibrous mat and a polyurethane composition applied all over the mat in an amount of 10 to 80% by weight based on the total weight of the mat and the polyurethane composition. The polyurethane composition contains 0.1 to 5.0% by weight of a surface active agent having a molecular weight of 2,500 to 30,000 which comprises a hydrophilic component and a hydrophobic component being combined by a urethane bond and/or an amide bond. The hydrophilic component is polyethylene oxides comprising 30 to 80% by weight of the surface active agent and the hydrophobic component is a member selected from the group consisting of a polyalkylene oxides excepting polyethylene oxides, aliphatic polyesters and mixtures thereof. The leathery sheet material has excellent flexibility, excellent antistatic properties and excellent soil resistance.

Abstract: Method and apparatus for producing a synthetic resin tube by deforming a strip of synthetic resin and joining both lateral surfaces of the deformed strip together while transporting the strip in its longitudinal direction.

Abstract: Method and apparatus for producing a synthetic resin tube by deforming a strip of synthetic resin and joining both laterally disposed edges of the deformed strip together while transporting the strip in its longitudinal direction.