3m Innovative Properties Company

Hikaru Takeda

Toshihiro Suwa

Problem: To provide a method for producing a laminate comprising a thick, highly transparent cured adhesive sheet exhibiting flow characteristics accompanied by satisfactory fluidity and satisfactory initial adhesion to an adherend before irradiation, and satisfactory hardness (in particular, a high storage modulus) after irradiation. Solution: A method for producing a laminate comprising a first substrate, a second substrate, and a cured adhesive sheet disposed therebetween, the method comprising steps of: forming into a sheet a radiation-curable adhesive sheet precursor comprising a polymer/monomer mixture comprising a partially polymerized (meth) acrylic monomer, a monomer having radiation reactive sites activated by short-wavelength radiation of a first wavelength or less, and a photoinitiator for initiating polymerization of the polymer/monomer mixture and the radiation reactive site-possessing monomer via radiation of a wavelength greater than the first wavelength; irradiating the precursor with radiation of a wavelength greater than the specific wavelength to polymerize the radiation-curable adhesive sheet precursor, forming a radiation-curable adhesive sheet; disposing the radiation-curable adhesive sheet adjacent to at least one surface of the first substrate; disposing the second substrate adjacent to a radiation-curable adhesive sheet; applying heat and/or pressure to the radiation-curable adhesive sheet; and irradiating the radiation-curable adhesive sheet with radiation comprising short-wavelength radiation of a first wavelength or less to obtain a cured adhesive sheet.

Growing community of inventors

Tokyo, Japan

Hikaru Takeda