Abstract: In a ball bearing resin cage, a first cage element and a second cage element are combined in the axial direction. The first cage element includes a pocket portion, a first coupling portion, and an engaged portion. The second cage element includes a pocket facing portion, a second coupling portion, and an engaging portion. The pocket portion includes a pair of protruding portions facing each other in the circumferential direction and forming a pocket surface, and a ball is held only by the pocket surface of the first cage element. The pocket facing portion includes a partial cylindrical surface having a radius larger than a sum of a radius of the ball and an axial movement amount of the first cage element and the second cage element.

Abstract: The present invention provides a dental self-adhesive resin cement having clinically-acceptable adherability for various adherends without pre-treatment with primers. Specifically, there is provided the dental self-adhesive composite resin cement comprising: (a) a radical polymerizable monomer, (b) a polymerizable monomer having a phosphonic acid group and/or a phosphoric acid ester group, (c) a polymerizable monomer having a dibasic acid carboxyl group, (d) a filler, and (e) a polymerization catalyst.

Abstract: The present invention provides a dental resin cement which is excellent in a mechanical strength, workability and storage stability, and a dental primer which significantly improves adhesiveness of the dental resin cement both to enamel and dentin of a tooth. According to the present invention, a salt of barbituric acid is used as a polymerization initiator in the dual-cure two-paste type dental resin cement being excellent in workability and storage stability to improve the storage stability, and a primer containing barbituric acid and amine is applied to a surface of a tooth to significantly improve adhesiveness of the dental resin cement both to enamel and dentin of teeth.

Abstract: A dental tone match checking material is provided that makes possible the elaboration of better esthetics than in the prior art. The present invention is a dental tone match checking material and relates to a dental tone match checking material, wherein the difference (n1?n0) between the refractive index n1 of this material and the refractive index no of the cured product from the dental cement that is checked with the dental tone match checking material is in the range from ?0.040 to +0.020.

Abstract: The present invention provides a dental self-adhesive resin cement having clinically-acceptable adherability for various adherends without pre-treatment with primers. Specifically, there is provided the dental self-adhesive composite resin cement comprising: (a) a radical polymerizable monomer, (b) a polymerizable monomer having a phosphonic acid group and/or a phosphoric acid ester group, (c) a polymerizable monomer having a dibasic acid carboxyl group, (d) a filler, and (e) a polymerization catalyst.

Abstract: The present invention provides a dental resin cement composition comprising at least two kinds of pastes, one kind of a paste comprising (a) 20 to 50 parts by weight of a polymerizable monomer composition and (b) 50 to 80 parts by weight of a filler consisting of an inorganic compound, or an organic composite comprising an inorganic compound, amounts of (a) and (b) being based on conversion of 100 parts by weight of the dental resin-based cement composition paste, and the filler (b) comprising (c) 2.0 to 10.0 parts by weight of fine silica particles based on the above conversion, and having (d) a yield viscosity of from 100 to 3,000 [Pa·s], and (e) a thixotropy index of 3.0 or more; and another kind of a paste having the same constituent features (a) to (c) and (e) except that the paste has (d) a yield viscosity of from 70 to 4,000 [Pa·s], wherein upon use, the at least two kinds of pastes are used by mixing them.

Abstract: The present invention provides a dental resin cement which is excellent in a mechanical strength, workability and storage stability, and a dental primer which significantly improves adhesiveness of the dental resin cement both to enamel and dentin of a tooth. According to the present invention, a salt of barbituric acid is used as a polymerization initiator in the dual-cure two-paste type dental resin cement being excellent in workability and storage stability to improve the storage stability, and a primer containing barbituric acid and amine is applied to a surface of a tooth to significantly improve adhesiveness of the dental resin cement both to enamel and dentin of teeth.

Abstract: In a wet friction material and a method therefor of the present invention, an excessive binder coating on the outermost surface layer of the friction material is removed or prevented while at least one of impregnation, drying and setting of a binder, and further the surface of the friction material is smoothed by means of heating, pressurizing and molding.

Abstract: In a wet friction material and a method therefor of the present invention, an excessive binder coating on the outermost surface layer of the friction material is removed or prevented while at least one of impregnation, drying and setting of a binder, and further the surface of the friction material is smoothed by means of heating, pressurizing and molding.

Abstract: In a wet friction material and a method therefor of the present invention, an excessive binder coating on the outermost surface layer of the friction material is removed or prevented while at least one of impregnation, drying and setting of a binder, and further the surface of the friction material is smoothed by means of heating, pressurizing and molding.

Abstract: In a wet friction material and a method therefor of the present invention, an excessive binder coating on the outermost surface layer of the friction material is removed or prevented while at least one of impregnation, drying and setting of a binder, and further the surface of the friction material is smoothed by means of heating, pressurizing and molding.