# US 10,872,633 B2 · Magnetic recording medium, laminate, and flexible device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,872,633 B2 - Document ID: US10872633B2 - Status: Granted - Kind: B2 - Application number: 16/099,625 - Filed: 2017-05-11 - Published: 2019-05-16 - Granted: 2020-12-22 - Earliest claimed: 2016-05-11 - Assignees: Sony Corporation - Applicants: Sony Corporation - Inventors: Eiji Nakashio; Yuta Akimoto; Tomoe Sato; Yoichi Kanemaki; Nobuyuki Sasaki; Masaru Terakawa; Kazuya Hashimoto; Katsunori Maeshima; Minoru Yamaga; Hikaru Terui; Hiroyuki Kobayashi - Web page: https://patentgrep.com/patent/US10872633B2 ## CPC - G11B 5/7369: {Two or more non-magnetic underlayers, e.g. seed layers or barrier layers} - G11B 5/735: characterised by the back layer {(magnetic recording media substrates G11B5/739)} - G11B 5/7368: {Non-polymeric layer under the lowermost magnetic recording layer (base layers having a non-magnetic layer under a soft magnetic layer G11B5/736; magnetic recording media substrates G11B5/739)} - G11B 5/78: Tape carriers - B32B 2307/734: Dimensional stability - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM ## Abstract A magnetic recording medium according to a first technique includes an elongated substrate having a first surface and a second surface, a first reinforcing layer disposed on the first surface, a second reinforcing layer disposed on the second surface, an adhesion suppressing layer disposed on the second reinforcing layer, and a recording layer disposed on the first reinforcing layer or the adhesion suppressing layer. ## Claims ### Claim 1 A magnetic recording medium comprising: an elongated substrate having a first surface and a second surface; a first reinforcing layer disposed on the first surface; a second reinforcing layer disposed on the second surface; an adhesion suppressing layer disposed on the second reinforcing layer; and a recording layer disposed on the first reinforcing layer or the adhesion suppressing layer, wherein a tensile stress as an internal stress acts on the first reinforcing layer and the second reinforcing layer, wherein the tensile stress of the second reinforcing layer is larger than the tensile stress of the first reinforcing layer, and wherein a compressive stress as an internal stress acts on the adhesion suppressing layer. ### Claim 2 (depends on 1) The magnetic recording medium according to claim 1, wherein the second reinforcing layer has an average thickness of 75 nm or more and 300 nm or less, and a ratio of an average thickness of the adhesion suppressing layer to the second reinforcing layer is 0.005 or more and 0.35 or less. ### Claim 3 (depends on 1) The magnetic recording medium according to claim 1, wherein the first reinforcing layer and the second reinforcing layer each contain at least one of a metal and a metal compound. ### Claim 4 (depends on 3) The magnetic recording medium according to claim 3, wherein the metal contains at least one of aluminum, copper, and cobalt. ### Claim 5 (depends on 1) The magnetic recording medium according to claim 1, wherein the adhesion suppressing layer contains carbon. ### Claim 6 (depends on 5) The magnetic recording medium according to claim 5, wherein the carbon is diamond-like carbon. ### Claim 7 (depends on 1) The magnetic recording medium according to claim 1, wherein the adhesion suppressing layer contains a metal oxide. ### Claim 8 (depends on 7) The magnetic recording medium according to claim 7, wherein the metal oxide includes at least one of aluminum oxide, copper oxide, and cobalt oxide. ### Claim 9 (depends on 1) The magnetic recording medium according to claim 1, wherein the recording layer is disposed on the first reinforcing layer, and the magnetic recording medium further comprises: a base layer disposed between the first reinforcing layer and the recording layer; and a back layer disposed on the adhesion suppressing layer. ### Claim 10 (depends on 1) The magnetic recording medium according to claim 1, wherein the recording layer is disposed on the adhesion suppressing layer, and the magnetic recording medium further comprises: a base layer disposed between the adhesion suppressing layer and the recording layer; and a back layer disposed on the first reinforcing layer. ### Claim 11 (depends on 1) The magnetic recording medium according to claim 1, wherein the first reinforcing layer and the second reinforcing layer have a same average thickness. ### Claim 12 (depends on 1) The magnetic recording medium according to claim 1, having a humidity expansion coefficient of 0 ppm/% RH or more and 4.8 ppm/% RH or less. ### Claim 13 (depends on 1) The magnetic recording medium according to claim 1, wherein the elongated substrate has a thickness of 10 μm or less. ### Claim 14 (depends on 1) The magnetic recording medium according to claim 1, wherein the adhesion suppressing layer has an average thickness of 1 nm or more and 100 nm or less. ### Claim 15 (depends on 1) The magnetic recording medium according to claim 1, wherein the adhesion suppressing layer includes a carbon thin film. ### Claim 16 (depends on 1) The magnetic recording medium according to claim 1, wherein the adhesion suppressing layer includes a first adhesion suppressing layer and a second adhesion suppressing layer, wherein the first adhesion suppressing layer disposed on the first reinforcing layer, wherein the recording layer disposed on the first adhesion suppressing layer, and wherein the second adhesion suppressing layer disposed on the second reinforcing layer. ### Claim 17 A laminate comprising: a substrate having a first surface and a second surface; a first reinforcing layer disposed on the first surface; a second reinforcing layer disposed on the second surface; and an adhesion suppressing layer disposed on the second reinforcing layer, wherein a tensile stress as an internal stress acts on the first reinforcing layer and the second reinforcing layer, wherein the tensile stress of the second reinforcing layer is larger than the tensile stress of the first reinforcing layer, and wherein a compressive stress as an internal stress acts on the adhesion suppressing layer. ### Claim 18 (depends on 17) The laminate according to claim 17, wherein the adhesion suppressing layer includes a carbon thin film. ### Claim 19 (depends on 17) A flexible device comprising the laminate according to claim 17. ### Claim 20 (depends on 18) A flexible device comprising the laminate according to claim 18.