Patent ID: 8017049

Claim:
A method of producing a resin product which includes a first resin layer partially covered with a second resin layer so that a boundary line between the first and second resin layers is visible from the outside, comprising: closing a first mold side having a recess with a second mold side; moving a slide core fitted in the recess of the first mold side toward the second mold side to an extracted position at a predetermined distance away from the second mold side to define a first cavity, the slide core including a dam to form a groove in the first resin layer; filling the first cavity with a first resin to form the first resin layer; moving only the slide core to a retracted position, thus defining a second cavity while the dam is partially disposed in the groove of the first resin layer; and filling the second cavity with a second resin to form the second resin layer and measuring a pressure of the second resin in a vicinity of a wedge ridge, and controlling pressure of injection of the second resin so as to maintain the pressure of the second resin within a predetermined range.