US 9,070,400 B2Granted

Method of manufacturing a magnetic recording medium

AssigneeFuji Electric Co., Ltd.

InventorsYuichi Hashizume, Kunio Hibino

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Abstract

A method of manufacturing a magnetic recording medium includes providing a substrate that is a magnetic recording medium substrate having a disc shape, having two main surfaces, and having defined therein a center hole; holding the center hole of the substrate from both main surfaces with two holding members that each have a disc shape to hold the substrate and to cover at least the periphery of the center hole adjacent to the two main surfaces of the substrate; and applying resist liquid simultaneously to both main surfaces of the substrate using spin coating to form a resist layer simultaneously on both main surfaces while maintaining the periphery of the center hole immediately adjacent to the two main surfaces of the substrate resist-free as an unapplied portion. The method enables efficient formation of uniform resist layers without defects on both faces of the substrate.

Claims19

Dependent claims

A method of manufacturing a magnetic recording medium, comprising the steps of:

providing a substrate that is a magnetic recording medium substrate having a disc shape, having two main surfaces, and having defined therein a center hole;
supporting the center hole of the substrate from both main surfaces with two holding members so as to hold the substrate in a vertical plane and to cover at least the periphery of the center hole adjacent to the two main surfaces of the substrate, the two holding members each having a circumferential tapered portion that tapers down toward a circumferential perimeter of the substrate, the tapered portions of the holding members being symmetrical with respect to the vertical plane;
engaging one of the two holding members with a rotation shaft of a drive portion of a spin coater and detachably mating the two holding members with one another at the rotation shaft, wherein one of the holding members has a lateral protrusion and the other holding member has a depression portion that interlocks with the protrusion to prevent relative rotation of the two holding members, wherein a rotational axis of the holding members passes through the protrusion and the depression;
and
applying resist liquid simultaneously to both main surfaces of the substrate using spin coating to form a resist layer simultaneously on both main surfaces by directing resist liquid toward the tapered portions of each of the two holding members while maintaining the periphery of the center hole immediately adjacent to the two main surfaces of the substrate substantially resist-free,
wherein the applying steps is conducted by directing the resist liquid toward locations on the tapered portions that are substantially equally distant from the rotational axis.

3 more elements

A method of manufacturing a magnetic recording medium, comprising the steps of:

providing a substrate that is a magnetic recording medium substrate having a disc shape, having two main surfaces, and having defined therein a center hole;
supporting the center hole of the substrate from both main surfaces with two holding members that hold the substrate in a vertical plane and cover at least the periphery of the center hole adjacent to the two main surfaces of the substrate, the two holding members each having a circumferential tapered portion that tapers down toward a circumferential perimeter of the substrate and each having at least one surface that has water-repellent properties, and at least one of the two holding members closing the center hole;
and
engaging one of the two holding members with a rotation shaft of a drive portion of a spin coater and detachably mating the two holding members with one another at the rotation shaft, wherein one of the holding members has a protrusion and the other holding member has a depression portion that interlocks with the protrusion to prevent relative rotation of the two holding members, wherein a rotational axis of the holding members passes through the protrusion and the depression;
and
applying resist liquid using spin coating simultaneously to both main surfaces of the substrate by spinning the substrate and by directing resist liquid toward the tapered portions of each of the two holding members from a horizontal direction to form a resist layer simultaneously on both main surfaces while maintaining the periphery of the center hole immediately adjacent to the two main surfaces of the substrate substantially resist-free,
wherein the tapered portions of the holding members are symmetrical with respect to the vertical plane, and
wherein the resist liquid is applied at locations on the tapered portions that are substantially the same distance from the rotation axis of the holding members.

5 more elements

Dependencies are inferred from the claim text.