Abstract: A retainer to be installed in a linear motion guide unit is disclosed which composed of embracing parts to hold a roller on diametrically opposite sides thereof, and connecting flanges joining the embracing parts together with one another. The embracing parts to hold the roller between them are each made with a first lip raised above any one side thereof, and a second lip raised above another side thereof. The first and second lips raised in opposite direction are placed in an offset or staggered relation with one another in lengthwise direction of the embracing part or in axial direction of the roller so as to be tough to suffer any distortion and/or damage on molding operation. The retainer can sustain ample lubricant near the lips. The embracing parts come into rolling-contact with the rolling surface of the roller while the connecting flanges come into sliding contact with axially opposite ends of the roller.

Abstract: A linear motion guide unit suitable for slender rollers, in which a tubular composition to define a return passage as well as a spacer piece to make a turnaround improve in property of retaining lubricant therein, thereby helping accomplish long-lasting service operation for lubrication. The tubular composition is composed of a tubular skeleton and a cellular member that fits into a window cut in the tubular skeleton. An end cap is comprised of an end cap major body, and two classes of spacer pieces nested in the end cap major body to define the turnaround passages. The spacer pieces of two classes are each made around outside surfaces thereof with some circular holes, which have functions of lubricant reservoirs, prevention of distortion or deformation caused in the molded spacer pieces, and ejector pinholes used to extract the molded spacer pieces out of the mold.

Abstract: A linear motion guide unit has a guide rail made of a thin plate, and a stopper construction installed detachably to the guide rail to prevent a slider from becoming untethered while on a sliding movement relative to the guide rail. A linear motion guide unit is disclosed in which a slider fits for linearly sliding movement in a guide rail made of a thin steel material formed in an U-shape in cross section, and there is provided a stopper construction to keep the slider against getting out of the guide rail. The stopper construction is comprised of a stopper pin installed detachably to the guide rail at any lengthwise end thereof to cause the stopper pin to bear against any fore-and-aft end of widthwise opposing side walls of the slider, whereby the slider comes to rest to prevent it from becoming untethered from the guide rail.

Abstract: A linear motion guide unit is disclosed, in which a slider fitting over a guide rail for movement is comprised of three components save rolling elements. The three components are joined together in the slider with using no fastener such as threaded fasteners, but just with fit-engagement that makes it possible to shrink the slider down in size. The three components are made up of a carriage made therein with raceway grooves and return passages, an upper component applied to the carriage to fit into recesses on the top surface of the carriage, and a lower component applied to the carriage to fit into recesses on the bottom surface of the carriage. The upper and lower components are joined together with the help of fit-engagement of hooks and hook holes, with holding firmly the carriage between them.

Abstract: A linear motion guide unit is disclosed in which a lower seal can be fastened easily, securely to a slider that travels relatively along a track rail. The slider is provided on a bottom surface thereof with a lug terminating in a hook that juts widthwise and extends lengthwise of the slider. The lower seal is made therein with a first hole allowing the lug to fit in there, and a second hole made connected to the first hole in longitudinal direction of the lower seal and made on at least any one lengthwise edge thereof with a tooth that will come into hooked engagement with the hook on the lug. The lug jutting out of the slider to fasten the lower seal is made at a flat bottom area near the track rail, which is over a space left open underneath the end cap.

Abstract: A linear motion guide unit has a guide rail made of a thin plate, and a stopper construction installed detachably to the guide rail to prevent a slider from becoming untethered while on a sliding movement relative to the guide rail. A linear motion guide unit is disclosed in which a slider fits for linearly sliding movement in a guide rail made of a thin steel material formed in an U-shape in cross section, and there is provided a stopper construction to keep the slider against getting out of the guide rail. The stopper construction is comprised of a stopper pin installed detachably to the guide rail at any lengthwise end thereof to cause the stopper pin to bear against any fore-and-aft end of widthwise opposing side walls of the slider, whereby the slider comes to rest to prevent it from becoming untethered from the guide rail.

Abstract: A linear motion guide unit is disclosed in which a lower seal can be fastened easily, securely to a slider that travels relatively along a track rail. The slider is provided on a bottom surface thereof with a lug terminating in a hook that juts widthwise and extends lengthwise of the slider. The lower seal is made therein with a first hole allowing the lug to fit in there, and a second hole made connected to the first hole in longitudinal direction of the lower seal and made on at least any one lengthwise edge thereof with a tooth that will come into hooked engagement with the hook on the lug. The lug jutting out of the slider to fasten the lower seal is made at a flat bottom area near the track rail, which is over a space left open underneath the end cap.

Abstract: The present invention relates to a decorative mold having an uneven pattern for forming a concrete surface with an uneven pattern by transfer. The present decorative mold is made of a molded product of polypropylene type foamed particles having a density of 0.02 to 0.06 g/cm.sup.3 and is formed with an uneven pattern on one surface for forming a pattern on a concrete surface by transfer, and in the surface having the uneven pattern for transfer, the total area, in terms of projected plane, of gap sections present in all the projected plane of the decorative mold accounts for less than 0.5% of all the area, in terms of projected plane, of the decorative mold. The maximum bending strength of the decorative mold determined by pressing from the undersurface opposite to the side having the uneven pattern is preferably 8.0 kgf/cm.sup.2 or more, and the average particle diameter of the polypropylene type resin foamed particles that are a raw material constituting the decorative mold is preferably 1 to 4 mm.

Abstract: Disclosed herein is a method of producing foamed particles of an ethylene-based resin, which have a high expansion ratio and are free from the formation of fine cells, by dispersing particles of the uncrosslinked ethylene-based resin, which are obtained using, as a base resin, an ethylene/.alpha.-olefin copolymer containing, as a comonomer component, 1.0-10 wt. % of an .alpha.-olefin having 4-10 carbon atoms, in a dispersion medium in the presence of a foaming agent in a closed vessel, heating the resultant dispersion to impregnate the resin particles with the foaming agent, and then releasing the resin particles into a region of a pressure lower than the internal pressure of the vessel at a foaming temperature not lower than the softening temperature of the resin particles, thereby expanding the resin particles.

Abstract: A filling apparatus for filling foamed particles of a thermoplastic resin into a mold. The apparatus includes a weigh hopper equipped with a weighing means, a foamed particle feeder adapted to control the amount of the foamed particles of the thermoplastic resin to be fed to the weigh hopper according to the weight of the foamed particles contained in the weigh hopper, a particle feed hopper adapted to temporarily keep a fixed weight of the foamed particles, which have been weighed in the weigh hopper, a holding hopper which acts as a pressurized tank, and a filling machine for filling the foamed particles into a mold. The filling apparatus allows for the successive weighing and pressurized containment of the foamed particles prior to being fed into the mold cavities.

Abstract: Disclosed herein is a production process of foamed polymer particles, wherein particles of a polymer, which contain a silica-alumina absorbent in which the molar ratio of SiO.sub.2 Al.sub.2 O.sub.3 is at least 1.15:1 are dispersed in a dispersion medium in the presence of carbon dioxide in a closed vessel, the resultant dispersion is heated to a temperature not lower than the softening temperature of the polymer to impregnate the polymer particles with carbon dioxide, and the polymer particles and the dispersion medium are then released into an atmosphere of a pressure lower than the internal pressure of the vessel, thereby expanding the polymer particles. The polymer may be an uncrosslinked propylene polymer, uncrosslinked, linear low-density polyethylene or crosslinked polymer.

Abstract: Prefoamed synthetic resin particles are produced by dispersing foamable resin particles in a dispersing medium within a closed vessel, said foamable resin particles containing a water-soluble inorganic substance and a blowing agent therein, and then releasing the foamable resin particles and the medium into an atmosphere of a pressure lower than that inside the vessel, whereby the thus-released foamable resin particles are allowed to undergo foaming.

Abstract: A process for the production of expanded resin particles is disclosed, wherein an aqueous dispersion containing expandable particles of a polyolefin resin is discharged at a temperature higher than the softening point of the resin from a high pressure condition to a low pressure condition to expand the expandable particles and wherein the expandable particles contain fine particles of an inorganic material coated with an agent selected from isopropyltriisostearic titanate, tetraoctadecyl titanate, acetoalkoxyaluminum diisopropylates, stearic acid, methyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, phenyltriethoxysilane and vinyltriethoxysilane.

Abstract: Pre-foamed particles of an uncrosslinked, linear low-density polyethylene have a crystalline structure characterized in that two endothermic peaks appear on a DSC curve obtained by differential scanning calorimetry of the pre-foamed particles (said DSC curve having been obtained by heating 1-5 mg of the pre-foamed particles to 220.degree. C. at a rate of 10.degree. C./min by a differential scanning calorimeter) and the energy at the endothermic peak on the higher-temperature side is 5 J/g or more. A process for the production of the pre-foamed particles of the uncrosslinked, linear low-density polyethylene is also disclosed.

Abstract: A method of forming pre-foamed beads of a polyethylene-base resin are disclosed. The polyethylene-base resin has been obtained by crosslinking a starting polyethylene-base resin having a density greater than 0.940 g/cm.sup.3 and the pre-foamed beads have a crosslinking degree of 10-45% gel content. The pre-foamed beads can provide a molded articles having excellent rigidity and dimensional accuracy and showing superb dimensional stability under heat.

Abstract: Pre-formed particles of an uncrosslinked, linear low-density polyethylene have a crystalline structure characterized in that two endothermic peaks appear on a DSC curve obtained by differential scanning calorimetry of the pre-foamed particles (said DSC curve having been obtained by heating 1-5 mg of the pre-foamed particles to 220.degree. C. at a rate of 10.degree. C./min by a differential scanning calorimeter) and the energy at the endothermic peak on the higher-temperature side is 5 J/g or more. A process for the production of the pre-foamed particles of the uncrosslinked, linear low-density polyethylene is also disclosed.

Abstract: Prefoamed particles of a polyolefin resin are produced by dispersing starting particles of the polyolefin resin, which contains a volatile foaming agent, in a dispersant in a pressure vessel, heating the resultant dispersion to a temperature of at least the softening point of the starting particles in said pressure vessel and then opening the vessel at one end thereof so as to release the starting particles and dispersant into an atmosphere of a pressure lower than the internal pressure of the vessel. The release of the starting particles and dispersant is performed while feeding a heating liquid.

Abstract: Prefoamed particles consisting essentially of an ethylene/propylene random copolymer, wherein said prefoamed particles are obtained by foaming particles of an ethylene/propylene random copolymer containing 1 to 4% by weight of random-copolymerized ethylene at a temperature in the range of from Tm - 15.degree. C. to Tm - 5.degree. C. (in which Tm is a temperature at which to terminate melting of the copolymer) and within the range of 141.degree. to 151.degree. C., and wherein said prefoamed particles have a crystal structure characterized in that in a DSC curve obtained by heating 1 to 3 mg of the copolymer prefoamed particles to 220.degree. C. at a heating rate of 10.degree. C./min. with a differential scanning calorimeter, there appear a peak (characteristic peak) characteristic of the copolymer and another peak (high temperature peak) at a higher temperature than a temperature at which the characteristic peak appears.

Abstract: An expansion-molded article of a polypropylene resin is produced by filling pre-foamed particles of the polypropylene resin, which have a crystalline structure featuring an inherent peak inherent to the polypropylene resin and a high-temperature peak on the temperature side higher than the temperature corresponding to the inherent peak on a DSC curve obtained by differential scanning calorimetry of the pre-foamed particles and a bulk density of 0.04 g/cm.sup.3 or higher and require melting energy of 8-12 J/g at the high-temperature peak, in a mold without applying any pretreatment to the pre-foamed particles to build up an internal pressure therein, and then heating the pre-foamed particles, whereby the pre-foamed particles are caused to expand into the expansion-molded article conforming with the mold. The pre-foamed particles may alternatively have a bulk density lower than 0.04 g/cm.sup.3 and require melting energy of at least 8 J/g.

Abstract: Expanded particles obtained by a method including the steps of: providing unexpanded particles formed of a polyethylene resin; impregnating the unexpanded particles with a liquid containing a polymerizable monomer including an acrylic monomer, and optionally a styrenic monomer; subjecting the impregnated polymerizable monomer to polymerization conditions so that at least a portion of the polymerizable monomer is grafted on the polyethylene resin to obtain modified polyethylene particles; and subjecting the modified polyethylene particles to an expansion treatment. Further expansion of the expanded particles within a mold gives a foamed article suitable for use as a consumable pattern in full mold casting.