# US 5,702,796 A · Modified multiphase bitumen composition and floor covering > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,702,796 A - Document ID: US5702796A - Status: Granted - Kind: A - Application number: 08/557,283 - Filed: 1995-11-14 - Granted: 1997-12-30 - Earliest claimed: 1990-04-10 - Assignees: Interface, Inc. - Inventors: Andrew Thompson - Web page: https://patentgrep.com/patent/US5702796A ## CPC - C08L 95/00: Compositions of bituminous materials, e.g. asphalt, tar, pitch - C08K 3/346: {Clay} - D06N 7/0071: {characterised by their backing, e.g. pre-coat, back coating, secondary backing, cushion backing} - D06N 7/0076: {the back coating or pre-coat being a thermoplastic material applied by, e.g. extrusion coating, powder coating or laminating a thermoplastic film} - D06N 2203/042: Polyolefin (co)polymers - D06N 2203/08: Bituminous material, e.g. asphalt, tar, bitumen - D06N 2205/20: Cured materials, e.g. vulcanised, cross-linked - D06N 2209/041: Conductive - D06N 2209/1628: Dimensional stability - D06N 2211/066: Floor coverings - Y10S 524/914: Floor covering compositions - Y10S 524/915: Carpet backing adhesives - Y10T 428/23979: Particular backing structure or composition - Y10T 428/23986: With coating, impregnation, or bond - Y10T 428/23993: Composition of pile or adhesive - Y10T 428/31815: Of bituminous or tarry residue - Y10T 442/20: Coated or impregnated woven, knit, or nonwoven fabric which is not [a] associated with another preformed layer or fiber layer or, [b] with respect to woven and knit, characterized, respectively, by a particular or differential weave or knit, wherein the coating or impregnation is neither a foamed material nor a free metal or alloy layer - Y10T 442/2369: Coating or impregnation improves elasticity, bendability, resiliency, flexibility, or shape retention of the fabric - Y10T 442/2418: Coating or impregnation increases electrical conductivity or anti-static quality - Y10T 442/2738: Coating or impregnation intended to function as an adhesive to solid surfaces subsequently associated therewith - Y10T 442/3707: Woven fabric including a nonwoven fabric layer other than paper - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - D06N: WALL, FLOOR, OR LIKE COVERING MATERIALS, e.g. LINOLEUM, OILCLOTH, ARTIFICIAL LEATHER, ROOFING FELT, CONSISTING OF A FIBROUS WEB COATED WITH A LAYER OF MACROMOLECULAR MATERIAL; FLEXIBLE SHEET MATERIAL NOT OTHERWISE PROVIDED FOR - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A floor covering having a bitumen composition as a backing layer, such as carpet tiles, which bitumen composition comprises straight run bitumen and a mixture of high density and low density polyethylene polymers blended and dispersed in the straight run bitumen as a continuous phase in an amount of up to about 12% by weight and which bitumen composition contains a minimum of about 40% by weight of a mineral filler material, such as limestone, and the bitumen composition having improved dimensional stability, adhesion, static loading and electrical conductivity and having lower cost and processing advantages. ## Claims ### Claim 1 A multiphase modified bitumen composition, which composition comprises: a) a straight run bitumen; b) a polymer mixture, the polymer mixture consisting essentially of a major amount of a low density polyethylene polymer (LDPE) and a minor amount of a high density polyethylene polymer (HDPE); c) the straight run bitumen forming a dispersed phase in a continuous phase of the polymer mixture; and d) the polymer mixture employed in an amount of up to about 12 percent by weight of the bitumen composition. ### Claim 2 (depends on 1) The composition of claim 1 wherein the straight run bitumen has a penetration value of up to 200 dmm. ### Claim 3 (depends on 1) The composition of claim 1 wherein the low density polyethylene is employed in an amount of about 3 to 9.5 percent of the bitumen composition. ### Claim 4 (depends on 1) The composition of claim 1 wherein the high density polyethylene is employed in an amount of from about 0.5 to 3 percent by weight of the bitumen composition. ### Claim 5 (depends on 1) The composition of claim 1 wherein the bitumen composition has a softening point of about 110.degree. C. to 128.degree. C. ### Claim 6 (depends on 1) The composition of claim 1 wherein the high density polyethylene has a melt flow index of greater than about 0.2 gr/10 min. and the low density polyethylene has a melt flow index of greater than 2 gr/10 min. ### Claim 7 (depends on 1) The composition of claim 1 wherein the composition includes a inert mineral filler therein. ### Claim 8 (depends on 1) The composition of claim 1 wherein the composition comprises a bitumen composition layer and includes a non-woven sheet material bonded to a surface of the layer. ### Claim 9 (depends on 1) The composition of claim 1 wherein the composition is characterized by viscosity of between about 6 to 125 pascal seconds at a temperature of 160.degree. C. to 180.degree. C. ### Claim 10 (depends on 1) A covering which comprises a sheet material having the modified multiphase bitumen composition of claim 1 as a coating layer. ### Claim 11 (depends on 1, 10) The covering of claim 10 wherein the covering comprises a carpet tile having a fibrous face surface and a back surface wherein the composition of claim 1 is secured to the back surface as a backing layer. ### Claim 12 (depends on 1) The composition of claim 1 which includes up to about 10 percent by weight of the bitumen composition of another hydrocarbon or blown bitumen. ### Claim 13 (depends on 7) The composition of claim 7 wherein the inert filler material comprises from about 40 to 65 percent by weight of the bitumen composition. ### Claim 14 (depends on 13) The composition of claim 13 wherein the filler material comprises limestone. ### Claim 15 (depends on 8) The composition of claim 8 wherein the sheet material comprises low melting point non-woven polypropylene sheet material. ### Claim 16 (depends on 1) The composition of claim 1 wherein the low density polyethylene has a density of about 0.90 to 0.930 g/cm.sup.3 and the high density polyethylene has a density of about 0.935 to 0.970 g/cm.sup.3.