Patent ID: 8231813

Claim:
A touch panel optical waveguide production method comprising the steps of: forming an under-cladding layer on a surface of a substrate; forming a core of a predetermined pattern on the under-cladding layer; forming a coating layer of an uncured photopolymerizable resin composition to form an over-cladding layer material over a surface of the under-cladding layer formed with the core by preparing an uncured photopolymerizable resin composition from an epoxy resin having a number average molecular weight (Mn) of about 1000 to about 5000, adjusting the viscosity of the uncured photopolymerizable resin composition to a viscosity of 300 to 2000 mPa·s by addition of a solvent, coating a portion of the surface of the under-cladding layer uncovered with the core with the viscosity adjusted uncured photopolymerizable resin composition as the over-cladding layer material in the coating layer forming step, and evaporating the solvent by heat-drying to form the coating layer, wherein the coating layer has a thickness of 100 to 500 μm; pressing a molding die composed of a light-transmissive material against the coating layer of the over-cladding layer material with a predetermined die surface of the molding die being properly positioned with respect to the coating layer, the die surface having a lens-shaped curved portion; exposing the coating layer to light through the molding die; and removing the molding die after the exposure, whereby an over-cladding layer without a void is formed in which the core is buried, the over-cladding layer including a curved surface which is curved towards the inner side of the substrate formed on a portion covering a distal end of the core buried therein and the over-cladding layer has a thickness of 50 to 2000 μm.