UACJ and Furukawa Electric Assigned Three Patents

Aluminum alloy sheet for magnetic disk and production method, and magnetic disk using said aluminum alloy sheet for magnetic disk
UACJ Corp., Tokyo, Japan, and Furukawa Electric Co. Ltd., Tokyo, Japan, has been assigned a patent (11,361,791) developed by Kitawaki, Kotaro, Yonemitsu, Makoto, Hatakeyama, Hideyuki, Toda, Sadayuki, Sakamoto, Ryo, and Fujii, Yasuo, Tokyo, Japan, for a “Aluminum alloy sheet for magnetic disk and production method therefor, and magnetic disk using said aluminum alloy sheet for magnetic disk.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “An aluminum alloy sheet for a magnetic disk includes an aluminum alloy comprising 0.10 to 3.00 mass % (hereafter simply “%”) of Fe, 0.1 to 3.0% of Mn, 0.003 to 1.000% of Cu, and 0.005 to 1.000 s % of Zn, wherein second phase particles having a maximum diameter of 100 .mu.m or more and 300 .mu.m or less are dispersed at a distribution density of 50 particles/mm.sup.2 or less in a region (A) occupying 25% or less of a sheet thickness from a sheet thickness center plane to opposite surfaces of the sheet, second phase particles having a maximum diameter of 100 .mu.m or more and 300 .mu.m or less are 0 particles/mm.sup.2 in a region (C) that is obtained by excluding the region (A) from a region (B) occupying 50% or less of the sheet thickness from the sheet thickness center plane to the opposite surfaces of the sheet, and the amount of Mn solid solution is 0.03 mass % or more.”

The patent application was filed on July 24, 2019 (17/262,971)

Aluminum alloy sheet for magnetic disk and production method and magnetic disk using said aluminum alloy sheet for magnetic disk
UACJ Corp., Tokyo, Japan, and Furukawa Electric Co. Ltd., Tokyo, Japan, has been assigned a patent (11,341,995) developed by Kitawaki, Kotaro, Igarashi, Yu, Kamiya, Keisuke, Matsui, Yu, Yonemitsu, Makoto, Sakamoto, Ryo, Hatakeyama, Hideyuki, and Ota, Hiroki, Tokyo, Japan, for “aluminum alloy sheet for magnetic disk and production method therefor, and magnetic disk using said aluminum alloy sheet for magnetic disk.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “An aluminum alloy sheet for a magnetic disk, a method for manufacturing same, and a magnetic disk using same. The aluminum alloy sheet is made of an aluminum alloy comprising 0.10 to 3.00 mass % of Fe, 0.003 to 1.000 mass % of Cu, and 0.005 to 1.000 mass % of Zn, with a balance of Al and unavoidable impurities, wherein a value obtained by dividing a difference in an area ratio (%) of second phase particles between a region (A) and a region (B) by an average value of area ratios (%) of second phase particles in the regions (A) and (B) is 0.05 or less, the region (A) being a region from a sheet thickness center plane to a front surface of the sheet, and the region (B) being a region from the sheet thickness center plane to a rear surface of the plate.”

The patent application was filed on October 15, 2019 (17/284,187).

Aluminum alloy substrate for magnetic disk, disk drive, manufacturing aluminum alloy substrate for magnetic disk, and measuring aluminum alloy substrate for magnetic disk
Furukawa Electric Co., Ltd.,Tokyo, Japan, and UACJ Corp., Tokyo, Japan, has been assigned a patent (11,335,367) developed by Imakawa, Kimie, Nakamura, Toshihiro, Takahashi, Hideki, Yoshimura, Keita, Kumagai, Wataru, Kitamura, Naoki, and Kitawaki, Kotaro, Tokyo, Japan, for “aluminum alloy substrate for magnetic disk, disk drive device, method for manufacturing aluminum alloy substrate for magnetic disk, and method for measuring aluminum alloy substrate for magnetic disk.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “An aluminum alloy substrate (1) for magnetic disk satisfies at least two of three inequalities of an inequality group [A] and satisfies all of four inequalities of an inequality group [B], or satisfies at least two of the three inequalities of the inequality group [A] and satisfies all of four inequalities of an inequality group [C], when a plate thickness of the disk at a position (b1) is defined as t.sub.b1, a plate thickness at a position (b2) is defined as t.sub.b2, a plate thickness at a position (b3) is defined as t.sub.b3, a plate thickness at a position (a1) is defined as t.sub.a1, a plate thickness at a position (a2) is defined as t.sub.a2, and a plate thickness at a position (a3) is defined as t.sub.a3.”

The patent application was filed on September 22, 2020 (17/028,885).