Abstract: A noise reduction sheet includes a flexible sheet containing a soft magnetic material, in which a plurality of first grooves extending in a first direction, a plurality of second grooves extending in a second direction, and a plurality of third grooves extending in a third direction are provided on a first surface of the sheet, the first surface is divided into a plurality of regular triangular regions by the first grooves, the second grooves, and the third grooves, and each of the first grooves, the second grooves, and the third grooves has a cross-sectional shape in which a groove width increases toward an opening along a depth direction of the groove.

Abstract: One of the objects of the present invention is to offer novolak type phenolic resins which use phenols and aldehydes as raw materials and give narrow molecular weight distributions.The novolak type phenolic resins of the present invention are those obtained by condensation reaction of phenols with aldehydes in the presence of an oxycarboxylic acid having carboxyl groups, --COOH, and alcoholic hydroxyl groups, --OH, in one molecule. Thus obtained novolak type phenolic resins show narrow molecular weight distributions, lower viscosity in molten state and, as a consequence, uniformity in curing time.

Abstract: One of the objects of the present invention is to offer novolak type phenolic resins which use phenols and aldehydes as raw materials and give narrow molecular weight distributions.The novolak type phenolic resins of the present invention are those obtained by condensation reaction of phenols with aldehydes in the presence of an oxycarboxylic acid having carboxyl groups, --COOH, and alcoholic hydroxyl groups, --OH, in one molecule. Thus, obtained novolak type phenolic resins show narrow molecular weight distributions, lower viscosity in molten state and, as a consequence, uniformity in curing time.

Abstract: One of the objects of the present invention is to offer novolak type phenolic resins which use phenols and aldehydes as raw materials and give narrow molecular weight distributions.The novolak type phenolic resins of the present invention are those obtained by condensation reaction of phenols with aldehydes in the presence of an oxycarboxylic acid having carboxyl groups, --COOH, and alcoholic hydroxyl groups, --OH, in one molecule. Thus obtained novolak type phenolic resins show narrow molecular weight distributions, lower viscosity in molten state and, as a consequence, uniformity in curing time.