Abstract: Disclosed is a sheet for producing a multilayer optical recording medium having a repeating structure wherein a plurality of optical recording layers are laminated. The sheet for a multilayer optical recording medium has a structure having a unit wherein an optical recording layer and an adhesive layer are laminated, or a structure having a unit wherein an optical recording layer, a barrier layer and an adhesive layer are laminated in this order. The maximum height roughness (Rz) of the optical recording layer or the barrier layer is not more than 500 nm. A multilayer optical recording medium is produced by using the sheet for a multilayer optical recording medium. Also disclosed is a sheet for producing, with high precision, a high-quality multilayer optical recording medium having a repeating unit wherein a plurality of optical recording layers containing a multiphoton absorbing material are laminated. A multilayer optical recording medium is also produced by using this sheet.

Abstract: It is an object to provide an optical recording medium-producing sheet that enables a protective layer or stamper-receiving layer to be formed easily and inexpensively and gives a good yield. A composition having an energy ray-curable component as a principal component thereof is applied onto a substrate 12, a coating layer thus obtained is irradiated with energy rays so as to semi-cure the energy ray-curable component, thus forming an energy ray-curable layer 11 having an adhesive strength of not less than 10 mN/25 mm, and then a substrate 12? is superposed onto the energy ray-curable layer 11, whereby an optical recording medium-(optical disk-) producing sheet 1 is obtained.

Abstract: A double coated pressure sensitive adhesive tape comprising pressure sensitive adhesive layers which comprise an acrylic ester-based copolymer having a weight-average molecular weight of 700,00 or greater and a content of a butyl acrylate unit of 90% by mass or greater and 40 to 60% by mass of a tackifier as main components and are disposed on both faces of a core material, wherein the thickness of the entire tape including the core material and the adhesive layers is 30 ?m or smaller, and the thickness of the adhesive layer on each face is 2 to 10 ?m. The tape is transparent and thin, is advantageously used for fixing members of portable terminals such as portable telephones and PDA and thin film displays, laminating substrates in optical disks and fixing polarizing plates and exhibits excellent adhesive strength and holding power at high temperatures.