Matsushita Electric Industrial Co., Ltd.

Tetsuya Kamimoto

Shinya Hasegawa

Hideo Torii

Mikie Kanai

Hiroshi Onishi

A Bismuth glass composition including 0.5 to 14 wt % of SiO, 3 to 15 wt % of BO, 4 to 22 wt % of ZnO, 55 to 90 wt % of BiOand 4 wt % or less of AlO, and further including 5 wt % or less of an oxide of Group A, 12 wt % or less of an oxide of Group B and 0.1 to 10 wt % of an oxide of Group C, wherein the oxide of Group A is at least one selected from the group consisting of LiO, NaO and KO, the oxide of Group B is at least one selected from the group consisting of MgO, CaO, SrO and BaO, and the oxide of Group C is at least one selected from the group consisting of ScO, YO, LaO, CeO, PrO, NdO, SmO, EuO, GdO, TbO, DyO, HoO, ErO, TmO, YbOand LuO.

Bismuth glass composition, and magnetic head and plasma display panel including the same as sealing member

A magnetic head for a magnetic recording/reproducing device to conform to high-density recording, wherein a metal magnetic film with a high saturation flux density is employed and the mechanical strength of the sealing glass for magnetic heads, is improved thereby achieving a high reliability, high performance magnetic head. Also, this is provided a magnetic recording/reproducing device utilizing the magnetic head. Sealing glass for magnetic heads comprising, by oxide conversion, 17.2 to 25 wt % of SiO, 1 to 10 wt % of BO, 58 to 75 wt % of PbO, 0.2 to 7 wt % of at least one of AlOand ZnO, and 0.2 to 5 wt % of at least one of NaO and KO, and a magnetic head and magnetic recording/reproducing device which utilize the sealing glass.

Sealing glass for magnetic head, magnetic head, and magnetic recording/reproducing device

In order to provide a practically lead-free glass composition having a low softening point and an excellent water resistance for use in various parts of electronic equipment and a magnetic head using the same, a glass composition is provided, which contains 0.5 to 14 wt % of SiO , 3 to 15 wt % of B O , 4 to 22 wt % of ZnO, 55 to 90 wt % of Bi O , 0 to 4 wt % of Al O , 0 to 5 wt % of at least one selected from the group consisting of Li O, Na O and K O, and 0 to 15 wt % of at least one selected from the group consisting of MgO, CaO, SrO and BaO.

Glass composition, sealing glass for magnetic head and magnetic head using the same

Because of its composition that is liable to be crystallized and therefore has a low strength, a conventional sealing glass for magnetic head has a problem in that in a manufacturing process for manufacturing a magnetic head having a narrow track width and a short gap length corresponding to the high-density recording in recent years with high accuracy, cracks are liable to be developed in a sealing glass portion by an impact caused in cutting and grinding a head chip. By using glass having a composition of 13 to 17 wt % SiO , 5 to 6.8 wt % B O , 70 to 77 wt % PbO, 0.1 to 5 wt % of at least one of Al O and ZnO, and 0.1 to 3 wt % of at least one of Na O and K O as a front sealing glass and using glass having a composition of 3 to 9 wt % SiO , 11 to 17 wt % B O , 66 to 77 wt % PbO, and 3 to 15 wt % of at least one of Al O and ZnO as a back sealing glass, a high-performance magnetic head having a high strength can be provided in high yields.

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Hirakata, Japan

Tetsuya Kamimoto