Abstract: A hand-held dental instrument is used for supporting a working tool and driving it according to a relative movement, including at least first fluid conveying means for conveying fluids through a body from the proximal end of the body towards fluid projection means. The first fluid conveying means include an upstream fluid conveying channel, a downstream fluid conveying channel, as well as a fluid collection radial chamber provided in the body between the upstream fluid conveying channel and the downstream fluid conveying channel. A filtration pin is mounted in the fluid collection radial chamber with a clearance allowing for the through-flow and the filtration of the fluids between the upstream fluid conveying channel and the downstream fluid conveying channel.

Abstract: Polyamide-based compositions, well suited for molding into a variety of shaped articles useful, e.g., in the electrical and electronics industries, contain an effective flame-retardant amount of red phosphorus and a corrosion/migration-reducing amount of at least one zinc compound selected from among zinc oxide, zinc sulfide and an oxygen-containing zinc salt, e.g., zinc borate.

Abstract: Fire-resistant polyamide compositions contain red phosphorus, a lanthanide-based compound, optionally glass fibers, and a hydrotalcite stabilizer having the general formula: Mg.sub.(1-a) Al.sub.a (OH).sub.2 A.sub.a/2.pH.sub.2 O in which A=SO.sub.4.sup.2- or CO.sub.3.sup.2-, O<a.ltoreq.0.5 and O<p<1; shaped articles produced therefrom exhibit an excellent compromise of properties in respect of fire resistance, resilience, arc tracking resistance and aging behavior in a hot and humid atmosphere.

Abstract: Flameproofed polyamide-based molding compositions contain a fireproofing amount of a red phosphorus, at least one lanthanide compound, a stabilizing amount of talc and zinc sulfide and/or zinc oxide, and are well adopted for conversion into useful shaped articles presenting an attractive combination of properties in respect of flame resistance, resilience, arc tracking resistance and surface appearance.

Abstract: Mixed polyester molding compositions comprising at least a pair of structurally different thermoplastic polyesters are stabilized against transesterification, whether during formulation or the downstream molding thereof, by having incorporated therein an effective amount of at least one mono-, di- or triester of orthophosphoric acid.

Abstract: Polymers comprising polyoxazolidone and carbodiimide recurring units of the formula: ##STR1## are prepared from polyisocyanates and polyepoxides. Non-friable, low density fire resistant foams are prepared directly from the polymers of the invention without the equisite addition of pore-forming agents.