Patent ID: 7726441

Claim:
An acoustic vibratory plate, comprising: at least first, second and third laminated bodies layered, wherein said first and third laminated bodies are formed of a biaxially stretched polyester (PET) film, said second laminated body is formed of a polyester-based adhesive for laminates composed of a polyester resin (LA) and is a polymer material higher than the polymer material forming said first and third laminated bodies in dynamic internal loss, a thickness of each of the first and third laminated bodies is greater than a thickness of the second laminated body, said first, second, and third laminated bodies generate a light interference phenomenon and exert a decorative function when reflecting light, and a ratio ξ of a thickness of the LA to a thickness of the PET film is defined by the equation: ξ = - ( 5 ⁢ aA - 3 ⁢ a ) - ( 5 ⁢ aA - 3 ⁢ a ) 2 - 4 ⁢ A ⁡ ( 4 ⁢ a 2 ⁢ A + 6 ⁢ aA - 6 ⁢ a ) 2 ⁢ ( 4 ⁢ a 2 ⁢ A + 6 ⁢ aA - 6 ⁢ a ) , where a is a ratio of an elastic modulus of the LA to an elastic modulus of the PET film and A is a ratio of an internal loss of a structure including the first, second, and third laminated bodies to an internal loss of the LA.