# US 7,608,654 B2 · Halogen-free flame retardant polycarbonate compositions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,608,654 B2 - Document ID: US7608654B2 - Status: Granted - Kind: B2 - Application number: 10/578,610 - Filed: 2003-11-07 - Published: 2007-04-12 - Granted: 2009-10-27 - Earliest claimed: 2003-11-07 - Assignees: Italamatch Chemicals S.p.A. - Inventors: Silvestro Costanzi; Maurizio Leonardi - Web page: https://patentgrep.com/patent/US7608654B2 ## CPC - C08K 3/32: Phosphorus-containing compounds - C08K 5/523: with hydroxyaryl compounds - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) ## Abstract The present invention relates to a thermoplastic halogen-free flame retardant composition comprising at least an hypophosphorous acid metal salts as halogen-free flame retardant agent, and at least an aromatic polycarbonate s resin and/or its blends. The flame retardant composition may in addition comprise additives and fillers. The invention also refers to moulded thermoplastic articles made by using the flame retardant composition. ## Claims ### Claim 1 Thermoplastic composition comprising at least an hypophosphorous acid metal salts as halogen-free flame retardant agent, and without the presence of a nitrogen containing flame-retardant agent, and at least an aromatic polycarbonate resin wherein said hypophosphorous acid metal salt has an average particle size of the powder (d50%) lower than 40 μm and an highest particle size below 100 μm. ### Claim 2 (depends on 1) Thermoplastic composition according to claim 1, wherein said aromatic polycarbonate resin is blended with a graft copolymer styrenic resin and that the polycarbonate resin/graft copolymer styrenic resin ratio ranges from 60/40 to 90/10. ### Claim 3 (depends on 2) Thermoplastic composition according to claim 2, wherein said polycarbonate resin is obtained by reaction of bis(hydroxyphenyl)alkanes, 2,2bis(4-hydroxyphenyl)propane (bisphenolA), bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydrophenyl)ethane, hydroquinone, resorcinol or catecol. ### Claim 4 (depends on 1) Thermoplastic composition according to claim 1, wherein said polycarbonate resin is a recycled polycarbonate materials, mixed with virgin polycarbonate polymer or blended with an impact modifier resin. ### Claim 5 (depends on 2) Thermoplastic composition according to claim 2, wherein said graft copolymer styrenic resin are selected from impact resistant polystyrene (HIPS), ABS resins, and MBS resins. ### Claim 6 (depends on 2) Thermoplastic composition according to claim 2, wherein said styrenic resin amount ranges from 10% to 40% by weight based on the weight of total resins. ### Claim 7 (depends on 1) Thermoplastic composition according to claim 1, wherein said metal is an alkaline metal belonging to the first, second and third main group or second, seventh, eighth subgroup of the periodic table of the elements. ### Claim 8 (depends on 7) Thermoplastic composition according to claim 7, wherein said metal is selected from Ca, Ba, Mg, Al, Zn, Fe, and B. ### Claim 9 (depends on 8) Thermoplastic composition according to claim 8, wherein said hypophosphorous acid metal salt is calcium hypophosphite and/or aluminum hypophosphite. ### Claim 10 (depends on 1) Thermoplastic composition according to claim 1, wherein said hypophosphorous acid metal salt is present in an amount that ranges from 1% to 30% by weight on the weight of the composition. ### Claim 11 (depends on 1) Thermoplastic composition according to claim 1, wherein said hypophosphorous acid metal salt is present in combination with halogen-free organic phosphoric esters. ### Claim 12 (depends on 11) Thermoplastic composition according to claim 11, wherein said halogen-free organic phosphoric esters are selected from triphenylphosphate, (TPP), tricresyl phosphate, trixylilenphosphate, resorcinoldiphosphate, resorcinolbis diphenylphosphate, bisphenol A bis diphosphate, trimethylphosphate, tributylphosphate, and trioctylphosphate. ### Claim 13 (depends on 1) Thermoplastic composition according to claim 1, wherein said hypophosphorous acid metal salt has a d50% value below 20 μm and an highest particle size below 50 μm. ### Claim 14 (depends on 1) Thermoplastic composition according to claim 1, which also comprises additives and/or fillers, said additives being present in an amount ranging from 0.5 to 5% by weight on the weight of the composition, said fillers being present in an amount up to 50% by weight on the weight of the composition. ### Claim 15 (depends on 14) Thermoplastic composition according to claim 14, wherein said additives are selected from processing aids, heat and process stabilisers, UV stabilisers, antidripping agents, pigments, lubricants, mould releasing agents, colorants, and plasticizers. ### Claim 16 (depends on 1) Thermoplastic composition according to claim 1, which also comprises fluorine-containing ethylene polymers in an amount of up to 2%, based on the weight of thermoplastic composition. ### Claim 17 (depends on 16) Thermoplastic composition according to claim 16, wherein said fluorine-containing ethylene are selected from polytetrafluoroethylene (PTFE) or tetrafluoroethylene-hexafluoropropylene copolymers. ### Claim 18 (depends on 16) Thermoplastic composition according to claim 16, wherein said fluorine-containing ethylene has a particle size of from 0.1 μm to 10 μm. ### Claim 19 (depends on 14) Thermoplastic composition according to claim 14, wherein said fillers are selected from carbon fibers, glass fibers, glass beads, amorphous silica, kaolin, chalk, mica, calcinated kaolin, wollastonite, and talc. ### Claim 20 (depends on 1) Process for the preparation of a thermoplastic composition according to claim 1, wherein the starting components and the additional components are mixed and kneaded in predetermined ratios, extruded and pelletized. ### Claim 21 (depends on 20) Process according to claim 20, wherein the kneading temperature is between 240 and 290° C. ### Claim 22 (depends on 1) Thermoplastic articles obtained using a halogen-free flame retardant composition according to claim 1.