# US 8,785,538 B2 · Electromagnetic wave shielding thermoplastic resin composition and plastic article including the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,785,538 B2 - Document ID: US8785538B2 - Status: Granted - Kind: B2 - Application number: 12/488,656 - Filed: 2009-06-22 - Published: 2009-12-03 - Granted: 2014-07-22 - Earliest claimed: 2006-12-22 - Assignees: Cheil Industries Inc. - Applicants: Sang Wan Kim; Young Sil Lee - Inventors: Sang Wan Kim; Young Sil Lee - Web page: https://patentgrep.com/patent/US8785538B2 ## CPC - C08J 5/10: characterised by the additives used in the polymer mixture - B82Y 30/00: Nanotechnology for materials or surface science, e.g. nanocomposites - C08J 5/041: {with metal fibres} - C08K 3/041: {Carbon nanotubes} - C08K 7/06: Elements - C08J 2367/00: Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers - C08J 2369/00: Characterised by the use of polycarbonates; Derivatives of polycarbonates - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) ## Abstract Disclosed herein are an electromagnetic wave shielding thermoplastic resin composition and a plastic article including the same. The electromagnetic wave shielding thermoplastic resin composition comprises about 100 parts by weight of a thermoplastic resin comprising a polycarbonate resin, a polyester resin, or a combination thereof, about 1 to about 30 parts by weight of stainless steel fiber, and about 0.01 to about 10 parts by weight of carbon nanotubes. ## Claims ### Claim 1 An electromagnetic wave shielding thermoplastic resin composition comprising: about 100 parts by weight of a thermoplastic resin comprising a polycarbonate resin, wherein the thermoplastic resin may optionally comprise a polyester resin; about 5 to about 25 parts by weight of stainless steel fiber; and 1 to about 5 parts by weight of carbon nanotubes wherein an article prepared from the composition has an electromagnetic wave shielding performance of about 60 to about 90 dB, and a notched IZOD impact strength (⅛″) of about 5 to about 30 kgf·cm/cm measured in accordance with ASTM D256. ### Claim 2 (depends on 1) The electromagnetic wave shielding thermoplastic resin composition according to claim 1, wherein the thermoplastic resin includes an aromatic polycarbonate resin. ### Claim 3 (depends on 1) The electromagnetic wave shielding thermoplastic resin composition according to claim 1, wherein the polycarbonate resin is prepared by reacting phosgene, halogen formate, or diester carbonate with a diphenol compound represented by Formula 1 below: wherein A represents a single bond, C1-C5 alkylene, C1-C5 alkylidene, C5-C6 cycloalkylidene, —S— or —SO2—; X is halogen; and n is 0, 1 or 2. ### Claim 4 (depends on 1) The electromagnetic wave shielding thermoplastic resin composition according to claim 1, wherein the polycarbonate resin has a weight average molecular weight of about 15,000 to about 50,000 g/mol. ### Claim 5 (depends on 1) The electromagnetic wave shielding thermoplastic resin composition according to claim 1, wherein the stainless steel fiber is ferritic stainless steel fiber, austenitic stainless steel fiber, or a combination thereof. ### Claim 6 (depends on 1) The electromagnetic wave shielding thermoplastic resin composition according to claim 1, wherein the stainless steel fiber has a thickness of about 4 to about 25 μm and a length of about 3 to about 15 mm. ### Claim 7 (depends on 1) The electromagnetic wave shielding thermoplastic resin composition according to claim 1, wherein the carbon nanotubes are single-walled carbon nanotubes, double-walled nanotubes, multi-walled carbon nanotubes, or a combination thereof. ### Claim 8 (depends on 1) The electromagnetic wave shielding thermoplastic resin composition according to claim 1, wherein the carbon nanotubes have a thickness of about 1 to about 50 nm and a length of about 1 to about 25 μm. ### Claim 9 (depends on 1) A plastic article produced from the electromagnetic wave shielding thermoplastic resin composition according to claim 1. ### Claim 10 (depends on 1) The electromagnetic wave shielding thermoplastic resin composition according to claim 1, comprising 1 to 2 parts by weight of carbon nanotubes. ### Claim 11 A plastic article comprising: about 100 parts by weight of a thermoplastic resin matrix comprising a polycarbonate resin, wherein the thermoplastic resin may optionally comprise a polyester resin; and about 5 to about 25 parts by weight of stainless steel fiber and about 1 to about 5 parts by weight of carbon nanotubes, each being dispersed in the thermoplastic resin matrix, wherein the plastic article has an electromagnetic wave shielding performance of about 60 to about 90 dB, and a notched IZOD impact strength (⅛″) of about 5 to about 30 kgf·cm/cm measured in accordance with ASTM D256.