# US 4,396,671 A · White photographic paper support and method of producing same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,396,671 A - Document ID: US4396671A - Status: Granted - Kind: A - Application number: 06/277,113 - Filed: 1981-06-25 - Granted: 1983-08-02 - Earliest claimed: 1980-11-21 - Assignees: Felix Schoeller, Jr. GmbH & Co. KG - Inventors: Rudolph Wanka; Heinz Wilke; Wolfram Wysk; Uwe Jensen - Web page: https://patentgrep.com/patent/US4396671A ## CPC - G03C 1/79: Macromolecular coatings or impregnations therefor, e.g. varnishes - Y10T 428/25: Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles - Y10T 428/256: Heavy metal or aluminum or compound thereof - Y10T 428/258: Alkali metal or alkaline earth metal or compound thereof - Y10T 428/31895: Paper or wood - Y10T 428/31902: Monoethylenically unsaturated - G03C: PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES (for photomechanical purposes G03F); PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY (photographic processes characterised by the use or manipulation of apparatus classifiable per se in subclass G03B, see G03B; photomechanical production of textured or patterned surfaces G03F; electrophotography, magnetography G03G) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A photographic support material includes a base paper upon which a polyolefin coating is coated on at least one side. The coating includes titanium dioxide therein and at least one alkaline earth metal oxide in an amount of about 0.05-20% by weight of the coating, preferably calcium and/or magnesium oxide, and/or an alkaline earth metal carbonate in an amount of about 0.05-10% by weight of the coating, preferably calcium and/or magnesium carbonate. ## Claims ### Claim 1 Photographic support material comprising: a base paper; at least one polyolefin coating on at least one side of said paper; said coating including titanium dioxide therein and at least one material selected from the group consisting of an alkaline earth metal oxide and mixtures thereof in an amount of about 0.05 to 20% by weight of said coating. ### Claim 2 (depends on 1) The photographic support material of claim 1, wherein said alkaline earth metal oxide is calcium oxide. ### Claim 3 (depends on 1) The photographic support material of claim 1, wherein said alkaline earth oxide is magnesium oxide. ### Claim 4 (depends on 1) The photographic support material of claim 1, wherein said alkaline earth metal oxide is a mixture of at least two alkaline earth metal oxides. ### Claim 5 (depends on 1) The photographic support material of claim 1, wherein said polyolefin coating contains a mixture of an alkaline earth carbonate and an alkaline earth oxide. ### Claim 6 (depends on 1) The photographic support material of claim 1, wherein said coating is treated for the acceptance of a photographic coating thereon. ### Claim 7 (depends on 1) The photographic support material of claim 1, wherein said polyolefin coating also contains material from the group consisting of coloring pigments, optical brighteners and mixtures thereof. ### Claim 8 (depends on 1) The photographic support material of claim 1, wherein said polyolefin coating contains about 0.2 to 10% by weight of the coating of said alkaline earth metal oxide. ### Claim 9 (depends on 1) The photographic support material of claim 1, wherein both sides of said paper are coated with polyolefin. ### Claim 10 (depends on 9) The photographic support material of claim 9, wherein at least one of the coatings is treated for the acceptance of a photographic coating thereon. ### Claim 11 (depends on 1) The photographic support material of claim 1, wherein said polyolefin coating contains at least one material selected from the group consisting of calcium oxide and magnesium oxide, and mixtures thereof. ### Claim 12 (depends on 11) The photographic support material of claim 11, wherein both sides of said paper are coated with polyolefin. ### Claim 13 (depends on 11) The photographic support material of claim 11, wherein said coating is treated for the acceptance of a photographic coating thereon. ### Claim 14 (depends on 11) The photographic support material of claim 11, wherein said polyolefin coating contains about 0.2 to 10% by weight of the coating of said alkaline earth metal oxide. ### Claim 15 A method of making a photographic material comprising coating base paper with a polyolefin coating by extruding said coating through a fishtail die, said polyolefin coating including titanium dioxide therein and at least one material selected from the group consisting of an alkaline earth metal oxide and mixtures thereof in an amount of about 0.05 to 20% by weight of said coating. ### Claim 16 (depends on 15) The method of claim 15, wherein said polyolefin coating contains at least one material selected from the group consisting of calcium oxide and magnesium oxide, and mixtures thereof. ### Claim 17 (depends on 15) The method of claim 15, wherein said polyolefin coating contains about 0.2 to 10% by weight of the coating of said alkaline earth metal oxide.