Abstract: An apparatus for photopolymerizing synthetic materials, specifically dental materials containing camphor quinone or phosphine oxide as a photo-initiator, includes a light source constituted by a semiconductor base solid-state radiation emitter 12 which emits in the blue spectral range. Since the radiation emitter emits in a small useful spectral range only, any heat radiation is avoided. The overall device is formed as a small, light-weight and handy device with a built-in battery 15. The solid-state radiation emitter 12, which is preferably operated in the light emitting diode (LED) mode, may be arranged directly on the tip 20 of the apparatus which can be directed toward the treatment site.

Abstract: A process of preparing a substrate surface for a subsequent adhesive bond, coating or pouring operation, by applying to the substrate an adhesion promoting composition comprising either:(A), (B) and (C); or (A) and (C); or (B) and (C); or (B) of the following ingredients (A)-(C):(A) 0.01 to 90 wt. % of optionally silanized material with a particle size <5 .mu.m and a hardness greater than that of the substrate surface,(B) 20 to 100 wt. % of silanized, silicon-containing material with an average particle size of 2 to 2100 .mu.m,(C) an abrasion agent with a particle size 5 .mu.m as the remainder;wherein the quantities quoted are relative to the total weight of (A)-(C). In the process the composition is applied to the substrate surface using horizontal or predominantly horizontal forces of friction, so that an adhesion promoting layer is formed on the substrate surface.

Abstract: Curable compositions are described which contain a binder and a high propion of fillers having a mean grain size of <50 .mu.m. The filler proportion of the curable compositions is so high that they cannot be used for the intended purpose because of their high viscosity However, they can be liquefied by exposure to oscillation in the frequency range of 20 Hz to 20 MHz with an amplitude of 1 .mu.m to 5 mm so that they are workable and can be employed for the intended purpose.

Abstract: A pressure vessel includes a body 10 and a cover 12. An O-ring 20 surroung the upper opening 11 of the vessel body 10 cooperates with a diaphragm 21 sealingly inserted in the cover 12. The diaphragm 21 extends beyond the O-ring 20 in the radial direction inside the cover 12. When the vessel is pressurized, a pressure difference acts on the diaphragm 21 to press an annular plate 23 driven by the diaphragm 21 against the O-ring 20, while the cover 12 is secured by a bayonet locking 24, 25 against being lifted off the vessel body. The pressure inside the vessel is thus used to produce the sealing force. In the unpressurized condition, the cover 12 may be easily placed on the vessel body 10 without effort, and rotation about a small angle is sufficient for securing the cover. In case the bayonet locking has not been completely closed, pressure applied to the vessel will lift the cover 12 by a certain amount, thereby automatically releasing the seal.

Abstract: An apparatus for irradiating fluids includes a conduit (11) through which the fluid flows, in which a static mixer (21) is disposed and which passes through a cooling vessel (16) having an annular cross-section. This arrangement is surrounded by several U-shaped fluorescent tubes (19, 20), whose legs, extending parallel to the conduit, are distributed around the periphery of the conduit (11). The mixer (21) effects a highly turbulent flow, such that all parts of the fluid are uniformly irradiated with radiation. If the fluid is a glue which is to be preactivated by the radiation, then the turbulent flow and the reaction rate, which is reduced by the cooling, retard the setting of polymerized fluid components on the inner wall of the reaction conduit, and thereby also inhibit the gradual blockage of the conduit (11).

Abstract: A hand-held sand blasting device, which is particularly useful for treating mall surface areas, such as tooth faces in situ, includes a sand cartridge 20 adapted to be placed in a handle portion 10 of the device and rewardly sealed by a piston 34 which is adapted to be advanced by pressurized air. Part of the pressurized air flows along a longitudinal groove 25 formed in a wall of the handle portion 10 externally of the cartridge 20 and enters the cartridge through an opening 27 provided at a front portion thereof, where the relatively large cross-section of the main portion of the cartridge converges to the substantially smaller cross-section of a feed channel 28. The fine sand 21 is thus fluidized in this area and maintained flowable. Through the feed channel 28, the sand is supplied to a mixing chamber 30 where it is mixed with pressurized air and discharged through a nozzle pipe 33.

Abstract: In a process for the preparation of a substrate surface for the bonding thereof with an activatable adhesive, an adhesion promoter layer is applied by means of sandblasting with a sandblasting material to which an activator has been added. Optionally, said adhesion promoter layer may be subsequently silanized.

Abstract: A mixing apparatus for pastes comprises a mount (18) for a mixing container (19) supported on a rotor (10) for rotation relative to the rotor about an axis (16) which is eccentric with respect to the rotor axis (15). During a mixing phase, a transmission (20 . . . 22) causes the mount (18) to rotate about its eccentric axis (16) so that the mixing container (19) executes an overall circulatory reciprocation and the container contents (29) are subjected to a shaking motion. For a subsequent compression phase, the transmission (20 . . . 22) is switched-over while the rotor (10) continues to rotate, so that the mount (18) is now free to assume an orientation that is fixed with respect to the rotor (10) and in which the mixed paste is forced against a dispensing piston (55) provided in the container (19) and is thereby degassed.

Abstract: A container for preparing a substance mixed from components which are inilly separated comprises two chambers (54, 56) separated from each other by a partitioning structure (52). One chamber (54) holds a liquid component and is closed by a sheet (53) of plastics material, and the other chamber (56) holds a powdery component and forms a mixing chamber. An actuating member (58) is movably disposed within the partitioning structure (52). The actuating member (58) includes a seal (64, 66) which is locked in the rest and storage position of the container and is released when the actuating member is moved into its actuated position in which the sheet (53) is perforated. In the actuated position, the seal (64, 66) functions as a valve to permit the liquid component to enter the mixing chamber (56) while preventing parts of the mixture or components thereof from flowing back from the mixing chamber (56) into the first chamber (54).

Abstract: For anchoring a prosthesis within a bone by means of a bone cement (32), prothesis shaft has a surface which is formed by the surfaces of a plurality of spheres (23 . . . 25) partially penetrating each other and having radii which decrease from the proximal towards the distal shaft end. The transitional zones between adjacent spheres (23 . . . 25) are concavely rounded. This shape is especially suited for use with a glass ionomer-type bone cement, because the shaft exerts substantially only compressive forces on the cement, whereas tensile and notch stresses, with respect to which this kind of cement exhibits little resistance, are largely avoided.

Abstract: A device for repairing damages caused by stones on windshields comprises a syringe (10) the discharge opening (14) of which is inserted into an applicator (11) adhesively affixed to the windshield (29) by means of a sealing disk (12). The syringe (10) is pre-filled by the manufacturer with a predetermined amount of a liquid synthetic resin which is curable by light. By retracting the syringe plunger (17), a vacuum is created for removing air and moisture that may have penetrated into the damaged portion (30). In its rearmost position, the plunger (17) exposes a vent hold (23) formed in the wall of the syringe casing (13) so that the resin will then be urged into the damaged portion (30) by the ambient atmospheric pressure.