Apparatus and method for producing patterned molded articles

A method for producing patterned molded articles by using an apparatus including an injection mold having a first mold and a second mold to define therebetween a cavity into which is injected material to be molded, an unwind roll means unwinding a pattern film, a film introducing means for introducing the pattern film unwound from the unwind roll means to between the first mold and the second mold in a direction from an upstream side toward a downstream side of a surface of the first mold, relative to a direction of unwinding of the pattern film, a first clamp means located between the first mold and the second mold for pressing the pattern film which has been introduced by the film introducing means against the surface of the first mold, a cutting means, disposed either at a specified position on the upstream side of the surface of the first mold or at a specified position of the first clamp means opposite to the upstream side, for cutting off the pattern film on the upstream side of the surface of the first mold when the pattern film is pressed against the first mold by the first clamp means, a second clamp means disposed on the downstream side of the surface of the first mold for fixing a cut-off end portion of the pattern film, the film introducing means having a pinch means for grasping the cut-off end portion of the pattern film and a pinch means-driving means for reciprocatingly moving the pinch means between the upstream side and the downstream side of the first mold, said method comprising steps of:

• grasping said cut-off end portion of said pattern film by said pinch means;
• moving said pinch means, which has grasped said cut-off end portion of said pattern film, by drive of said pinch means-driving means in a direction from said upstream side toward said downstream side of said surface of said first mold;
• fixing said cut-off end portion of said pattern film by said second clamp means;
• releasing said pattern film from said pinch means and withdrawing said pinch means from between said first clamp means and said first mold by said pinch means-driving means;
• pressing said pattern film against said surface of said first mold by drive of said first clamp means and, when or after said pressing, cutting off said pattern film at said upstream side of said surface of said first mold by said cutting means;
• injecting molten resin into said cavity formed by mold-closing said first mold and said second mold;
• and
• releasing said pattern film from said first clamp means, thereby obtaining a patterned molded article.