Abstract: A vitrified bond tool including: (a) a support body; (b) a vitrified bond layer which is formed on a working surface of the support body; and (c) a plurality of abrasive grains which are held by the vitrified bond layer so as to be fixed relative to the working surface of the support body and which are spaced apart from each other with spacing between the adjacent ones of the abrasive grains. This vitrified bond tool is advantageously manufactured according to a method including the steps of (i) forming a pattern layer which includes a vitrified bond, in a predetermined pattern on the working surface of the support body; (ii) sprinkling the abrasive grains over the pattern layer before the pattern layer is dried; and (iii) firing the pattern layer and the abrasive grains which are bonded to the pattern layer and are arranged in the predetermined pattern on the working surface of the support body.

Abstract: A polishing pad enabling a highly precise optical endpoint sensing during the polishing process and thus having excellent polishing characteristics (such as surface uniformity and in-plane uniformity) is disclosed. A polishing pad enabling to obtain the polishing profile of a large area of a wafer is also disclosed. A polishing pad of a first invention comprises a light-transmitting region having a transmittance of not less than 50% over the wavelength range of 400 to 700 nm. A polishing pad of a second invention comprises a light-transmitting region having a thickness of 0.5 to 4 mm and a transmittance of not less than 80% over the wavelength range of 600 to 700 nm. A polishing pad of a third invention comprises a light-transmitting region arranged between the central portion and the peripheral portion of the polishing pad and having a length (D) in the diametrical direction which is three times or more longer than the length (L) in the circumferential direction.

Abstract: A vitrified bond tool including: (a) a support body; (b) a vitrified bond layer which is formed on a working surface of the support body; and (c) a plurality of abrasive grains which are held by the vitrified bond layer so as to be fixed relative to the working surface of the support body and which are spaced apart from each other with spacing between the adjacent ones of the abrasive grains. This vitrified bond tool is advantageously manufactured according to a method including the steps of (i) forming a pattern layer which includes a vitrified bond, in a predetermined pattern on the working surface of the support body; (ii) sprinkling the abrasive grains over the pattern layer before the pattern layer is dried; and (iii) firing the pattern layer and the abrasive grains which are bonded to the pattern layer and are arranged in the predetermined pattern on the working surface of the support body.

Abstract: A vitrified bond tool including: (a) a support body; (b) a vitrified bond layer which is formed on a working surface of the support body; and (c) a plurality of abrasive grains which are held by the vitrified bond layer so as to be fixed relative to the working surface of the support body and which are spaced apart from each other with spacing between the adjacent ones of the abrasive grains. This vitrified bond tool is advantageously manufactured according to a method including the steps of (i) forming a pattern layer which includes a vitrified bond, in a predetermined pattern on the working surface of the support body; (ii) sprinkling the abrasive grains over the pattern layer before the pattern layer is dried; and (iii) firing the pattern layer and the abrasive grains which are bonded to the pattern layer and are arranged in the predetermined pattern on the working surface of the support body.

Abstract: This invention relates to Trestatin A, Trestatin B and Trestatin C salts thereof and mixtures thereof as well as compositions containing at least one of the Trestatins A, B or C or a salt thereof. These compositions are useful for the inhibition of sucrase and inhibition of alpha-amylase.

Abstract: The present invention is concerned with a process for the manufacture of optically active .alpha.-hydroxycarboxylic acids, especially a process for the manufacture of optically pure D- or L-.alpha.-hydroxycarboxylic acids.