Nitto-denko Corporation

Tadao Takahashi

Kazumichi Kato

Kohei Doi

Hideyuki Tokuyama

Kunio Nagasaki

Kiichiro Matsushita

Tetsuya Otsuka

Mika Okada

Tsunaki Kitahara

There is provided a foamed sheet which takes only a short time to recover the thickness thereof after being compressed, and even if being subjected to repeated impacts, hardly decreases in the impact absorption. The foamed sheet according to the present invention comprises a foamed body formed of a resin composition comprising: a thermoplastic resin a and a silicone-based compound b having not more than 2,000 siloxane bonds; and/or a thermoplastic resin a' having a silicone chain having not more than 2,000 siloxane bonds. The thermoplastic resin a is preferably at least one selected from the group consisting of acrylic polymers, rubbers, urethanic polymers and ethylene-vinyl acetate copolymers. The silicone-based compound b is preferably at least one selected from the group consisting of silicone oils, modified silicone oils and silicone resins.

Foamed sheet

A foamed sheet according to the present invention has a thickness of 30 to 500 &#x3bc;m and includes a foam. The foam has a density of 0.2 to 0.7 g/cm, an average cell diameter of 10 to 150 &#x3bc;m, and a peak top of loss tangent (tan &#x3b4;) occurring in a temperature range of from &#x2212;30&#xb0; C. to 30&#xb0; C., where the loss tangent is defined as the ratio of a loss modulus to a storage modulus determined at an angular frequency of 1 rad/s in dynamic viscoelastic measurement of the foam. The foam preferably has a maximum of the loss tangent (tan &#x3b4;) in the temperature range of from &#x2212;30&#xb0; C. to 30&#xb0; C. of 0.2 or more.

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Ibaraki, Japan

Tadao Takahashi