Nitto-denko Corporation

Akinori Nishio

Kazuyuki Kiuchi

Fumiteru Asai

Kunio Nagasaki

Tomokazu Takahashi

Takashi Habu

Toshio Shintani

Takashi Imoto

Akira Shoji

Kazyuki Kuichi

An identification sheet (X) according to the present invention includes a backing sheet () and a pressure-sensitive adhesive sheet (). The backing sheet () bears a distinguishing mark (M). The pressure-sensitive adhesive sheet () has a multilayer structure including a substrate layer () and a pressure-sensitive adhesive layer (). The pressure-sensitive adhesive layer () is removably attachable to the backing sheet (). The pressure-sensitive adhesive sheet () bears a distinguishing mark (M). The identification sheet (X) as above is suitable for keeping on surely providing the admissibility of evidence of a collected target material to be identified.

Sheet for identification

The present invention provides a substrate-less pressure-sensitive adhesive sheet for protection of semiconductor wafer, which is to be stuck to a front surface of a semiconductor wafer in grinding a back surface of the semiconductor wafer, the pressure-sensitive adhesive sheet consisting of a pressure-sensitive adhesive layer, in which the pressure-sensitive adhesive layer is formed of a UV-curable pressure-sensitive adhesive containing a polymer composed mainly of an acrylic monomer polymerizable compound, the pressure-sensitive adhesive force of a surface of the pressure-sensitive adhesive layer to be stuck to the front surface of the semiconductor wafer is larger than the pressure-sensitive adhesive force of the opposite surface thereof, and the pressure-sensitive adhesive layer has an initial elastic modulus of from 0.01 MPa to 500 MPa.

Substrate-less pressure-sensitive adhesive sheet for protection of semiconductor wafer, method for grinding back side of semiconductor wafer using pressure-sensitive adhesive sheet, and method for producing pressure-sensitive adhesive sheet

To provide a pressure-sensitive adhesive sheet which protects a ground, thin, fragile adherend from 'warping' and which can be removed from the fragile adherend after the completion of backgrinding without damaging and contaminating the fragile adherend. The pressure-sensitive adhesive sheetincludes a base layer A, a pressure-sensitive adhesive layer A, a base layer B, and a pressure-sensitive adhesive layer B arranged in this order, in which: the base layer A has a product of its Young's modulus at 25&#xb0; C. and its thickness of 1.0&#xd7;10to 4.0&#xd7;10N/m and a product of its Young's modulus at 80&#xb0; C. and its thickness of 2.8&#xd7;10N/m or less; the pressure-sensitive adhesive layer A has a shear modulus at 80&#xb0; C. of 0.2 MPa or less; the base layer B has a product of its Young's modulus at 25&#xb0; C. and its thickness of smaller than that of the base layer A and has, upon 80&#xb0; C. heating, a shrink percentage in MD and a shrink percentage in TD of each 20% or more; and the pressure-sensitive adhesive layer B has a Young's modulus at 80&#xb0; C. of 10 MPa or more and an adhesive strength to a silicon wafer (180-degree peel at a tensile speed of 300 mm/min) of 0.2 N/10 mm or less.

Pressure-sensitive adhesive sheet, method of processing adherend with the pressure-sensitive adhesive sheet, and apparatus for stripping pressure-sensitive adhesive sheet

The present invention relates to a self-rolling pressure-sensitive adhesive sheet, including a shrinkable film layer; a restriction layer disposed on a side of the shrinkable film layer; and a pressure-sensitive adhesive layer disposed on the side of the restriction layer which is opposite to the side on which the shrinkable film layer is disposed. The self-rolling pressure-sensitive adhesive sheet is a releasable pressure-sensitive adhesive sheet, in which the pressure-sensitive adhesive layer or the pressure-sensitive adhesive layer after an adhesiveness decreasing treatment has a pressure-sensitive adhesive power (180&#xb0; C. peeling, against a silicon mirror wafer, tensile speed: 300 mm/min) of 6.5 N/10 mm or less, and in which the self-rolling pressure-sensitive adhesive sheet rolls up in one direction from an end to form one tubular roll or rolls up from two opposing ends toward a center of the two opposing ends to form two tubular rolls, when the self-rolling pressure-sensitive sheet is stimulated to induce the contraction of the shrinkable film layer.

Growing community of inventors

Ibaraki, Japan

Akinori Nishio