Abstract: A heated dental knife for trimming thermoplastic dental trays which has a heat sink temperature stabilizer and heating element designed to maintain a pre-selected blade temperature without adjustments under normal use in cutting such dental trays.

Abstract: A material holding apparatus comprising a receptacle and an integrated finger mount. A lip or groove is circumferentially added to disposable plastic cups used in the dental profession. The receptacle preferably includes projections which mate by snap fit with either the lip or groove of the disposable cups. The finger mount is made of a flexible material and is made with two arms extending from the base of the receptacle, arcing to form a ring. The ends of the arms approach one another, bur remain flexible so as to fit a wide variety of finger sizes. Alternatively, a single band may be used as the finger mount. With either embodiment, the finger mount is slipped over the finger of the use, usually a dental professional.

Abstract: By utilizing the process of the present invention a carbon black/resin masterbatch powder can be easily prepared on a commercial scale. This invention more specifically discloses a process for making a resin/carbon black masterbatch powder which comprises the steps of: (1) mixing the carbon black and the resin in an aqueous medium at an elevated temperature to produce an aqueous dispersion, with the proviso that the elevated temperature is above the melting point of the resin in the case of crystalline resins and with the proviso that the elevated temperature is above the softening point of the resin in the case of amorphous resins; (2) cooling the aqueous dispersion to a temperature which is below the melting point or the softening point of the resin; and (3) recovering the masterbatch powder from the aqueous dispersion. By utilizing the technique of this invention resin-composite particulates of syndiotactic-1,2-polybutadiene and carbon black can be easily prepared.

Abstract: A materials holding apparatus consisting of a receptacle, flange, and mount for use in the practice of dentistry capable of bringing the necessary implements to the operation at hand and making the requisite materials available for timely use, which can be worn on the finger or thumb of both left-handed and right-handed individuals with equal ease and remains stable and does not slip and slide around the finger or thumb. A protective cap is used in conjunction with the finger mounted apparatus to reduce spilling or splattering of the materials contained in the receptacle.

Abstract: A materials holding apparatus consisting of a receptacle, flange and mount for use in the practice of dentistry capable of bringing the necessary implements to the operation at hand and making the requisite materials available for timely use, which can be worn on the finger or thumb of both left-handed and right-handed individuals with equal ease and remains stable and does not slip and slide around the finger or thumb.

Abstract: Superior vulcanization agents for rubber are prepared by reacting sulfur with at least one olefin at 120.degree.-200.degree. C. in an aqueous reaction media with agitation. In one embodiment, the vulcanization agent comprises a sulfur/olefin adduct having from about 39% to about 46% by weight of free elemental sulfur level.

Abstract: Superior vulcanization agents for rubber are prepared by reacting sulfur with an olefin at 140.degree.-160.degree. C. in an aqueous reaction media in the presence of a basic catalyst and a dispersing agent.

Abstract: Superior vulcanization agents for rubber are prepared by reacting sulfur with an olefin at 140.degree.-160.degree. C. in an aqueous reaction media in the presence of a basic catalyst and a dispersing agent.