Abstract: A method of production of an aluminum alloy inhibiting oxidation loss of the alloy melt without the use of Be which is liable to affect the human health. When preparing an aluminum alloy melt containing Mg, the method adds to the alloy, Ca, Sr, and/or Ba in a composition ratio within a range enclosed by lines connecting four points illustrated in FIG. 1 of a point A (Ca: 18 at %, Sr: 0 at %, and Ba: 82 at %), point B (Ca: 14 at %, Sr: 34 at %, and Ba: 52 at %), point C (Ca: 33.8 at %, Sr: 66.2 at %, and Ba: 0 at %), point D (Ca: 100 at %, Sr: 0 at %, and Ba: 0 at %) and excluding point D so as to adjust the Ca, Sr, and Ba components in the melt to include Ca: 0.001 to 0.5 mass % and one or both of Sr: 0.01 to 2.8 mass % and Ba: 0.01 to 7.83 mass %.

Abstract: The present invention relates to an aluminum die base material for a stamper having a component composition that contains 0.5% by weight to 3.0% by weight of Mg, the total amount of elements other than Mg, including unavoidable impurities, is 500 ppm or less, and the remainder is composed of Al, and a forged structure in which the average crystal grain size is 1000 ?m or less and the surface area ratio of second phase particles is 0.10% or less. According to the present application, a stamper can be provided in which, together with the crystal grain size of the aluminum being refined, the formation of second phase particles is inhibited, surface irregularities attributable to mirrored surface polishing are reduced, and a uniform relief pattern is formed by anodic oxidation treatment.

Abstract: Disclosed herein are a stamper which has anodized alumina formed on the surface thereof and which will not cause macroscopic unevenness or color unevenness on the transcribed surface; a method for producing the same; and a method for producing a molded material without macroscopic unevenness or color unevenness on the transcribed surface thereof by using such a stamper. The stamper includes alumina which has a microasperity structure and which is formed by anodization on the surface of a prototype aluminum mold having an aluminum purity of 99.5% or more, an average crystal-grain diameter of 1 mm or less, and an arithmetic mean surface roughness Ra of 0.05 ?m or less. The use of this stamper enables the production of a molded material which does not have macroscopic unevenness or color unevenness on the transcribed surface thereof and which is suitable for use as an antireflection article and the like.

Abstract: Provided is an Al alloy member with an excellent mechanical strength that is sufficient for use in large-scale manufacturing apparatuses. The Al alloy member is characterized in that, in mass %, Mg concentration is 5.0% or less, Ce concentration is 15% or less, Zr concentration is 0.15% or less, the balance comprises Al and unavoidable impurities, the elements of the unavoidable impurities are respectively 0.01% or less, and the Vickers hardness of the Al alloy member is greater than 30.

Abstract: The present invention relates to an aluminum die base material for a stamper having a component composition that contains 0.5% by weight to 3.0% by weight of Mg, the total amount of elements other than Mg, including unavoidable impurities, is 500 ppm or less, and the remainder is composed of Al, and a forged structure in which the average crystal grain size is 1000 ?m or less and the surface area ratio of second phase particles is 0.10% or less. According to the present application, a stamper can be provided in which, together with the crystal grain size of the aluminum being refined, the formation of second phase particles is inhibited, surface irregularities attributable to mirrored surface polishing are reduced, and a uniform relief pattern is formed by anodic oxidation treatment.

Abstract: A method of production of an aluminum alloy inhibiting oxidation loss of the alloy melt without the use of Be which is liable to affect the human health. When preparing an aluminum alloy melt containing Mg, the method adds to the alloy, Ca, Sr, and/or Ba in a composition ratio within a range enclosed by lines connecting four points illustrated in FIG. 1 of a point A (Ca: 18 at %, Sr: 0 at %, and Ba: 82 at %), point B (Ca: 14 at %, Sr: 34 at %, and Ba: 52 at %), point C (Ca: 33.8 at %, Sr: 66.2 at %, and Ba: 0 at %), point D (Ca: 100 at %, Sr: 0 at %, and Ba: 0 at %) and excluding point D so as to adjust the Ca, Sr, and Ba components in the melt to include Ca: 0.001 to 0.5 mass % and one or both of Sr: 0.01 to 2.8 mass % and Ba: 0.01 to 7.83 mass %.

Abstract: Provided is an Al alloy member with an excellent mechanical strength that is sufficient for use in large-scale manufacturing apparatuses. The Al alloy member is characterized in that, in mass %, Mg concentration is 5.0% or less, Ce concentration is 15% or less, Zr concentration is 0.15% or less, the balance comprises Al and unavoidable impurities, the elements of the unavoidable impurities are respectively 0.01% or less, and the Vickers hardness of the Al alloy member is greater than 30.

Abstract: Disclosed herein are a stamper which has anodized alumina formed on the surface thereof and which will not cause macroscopic unevenness or color unevenness on the transcribed surface; a method for producing the same; and a method for producing a molded material without macroscopic unevenness or color unevenness on the transcribed surface thereof by using such a stamper. The stamper includes alumina which has a microasperity structure and which is formed by anodization on the surface of a prototype aluminum mold having an aluminum purity of 99.5% or more, an average crystal-grain diameter of 1 mm or less, and an arithmetic mean surface roughness Ra of 0.05 ?m or less. The use of this stamper enables the production of a molded material which does not have macroscopic unevenness or color unevenness on the transcribed surface thereof and which is suitable for use as an antireflection article and the like.

Abstract: A non-adhesive tape holder (20) which comprises a drum body (21), a tape restraining member (22), a coil spring (23), and a rotation-preventing projection (30). The tape restraining member (22) is bent into a generally inclined U shape and includes a support shaft portion (32), a connecting portion (33), and a tape hold-down portion (34). The support shaft portion (32) is supported by the drum body (21) rotatably about an axis parallel to the axis of the drum body (21) in a position eccentric relative to the axis of the drum body (21). The coil spring (23) is housed in a spring-receiving recess (27) of the drum body (21) and elastically urges the tape restraining member (22) to rotate the tape restraining member (22) about the axis of the support shaft portion (32). The connecting portion (33) of the tape restraining member (22) rotated by the urging force of the coil spring (23) abuts against the rotation-preventing projection (30) movably toward and away from the rotation-preventing projection (30).