Patent ID: 8721816

Claim:
A method of producing a roll of an optical film laminate, comprising the steps: providing a roll of a separator film-attached optical film laminate which comprises a continuous web of an optical film laminate including a polarizing film which consists of a polyvinyl alcohol type resin layer and has a thickness of 10 μm or less and an absorption axis in a lengthwise direction of the optical film laminate, and a separator film attached to the optical film laminate through an adhesive layer, wherein the polarizing film is formed by performing an stretching sub-step of subjecting a laminate comprising a continuous web of a thermoplastic resin substrate and a polyvinyl alcohol type resin layer formed on the substrate, to a uniaxial stretching in a lengthwise direction of the laminate to attain a stretching ratio of 5.0 to 8.5 to thereby reduce a thickness of the polyvinyl alcohol type resin layer to 10 μm or less, and an absorption sub-step of causing a dichroic material to be absorbed in the polyvinyl alcohol type resin layer, and an adhesion force of the separator film with respect to the adhesive layer is weaker than an adhesion force of the optical film laminate with respect to the adhesive layer; peeling the separator film from the optical film laminate in such a manner as to allow the adhesive layer to adhere to a side of the polarizing film, while unrolling the optical film laminate from the roll and feeding the unrolled optical film laminate in the lengthwise direction; in a state after the separator film is peeled, detecting a defect existing in the optical film laminate and the adhesive layer; upon detection of a defect in the continuous web of optical film laminate, recording a position of the defect; after the step of detecting a defect, attaching a separator film to the adhesive layer to form a separator film-attached optical film laminate; and winding the formed separator film-attached optical film laminate into a roll.