Patent ID: 7306553
Filing Date: 2007-12-11
Classification: A61J,B29B,B29C,B29K,B29L,B31B,Y10T

Abstract:
1. A bag-making method for producing a bag by melt-bonding and thereby integrating a mouth member formed of a preliminarily heated synthetic resin and a bag unit formed of a flexible film, said method comprising; a preliminary heating step of softening the synthetic resin of the mouth member at the part to be melt-bonded to the bag unit, which is a melt-bonding part of mouth member, while preventing the synthetic resin of the mouth member at the end part in the bag side, which is an end part of mouth member, from being softened at the preliminary heating, and a melt-bonding step of inserting the preliminarily heated mouth member into the opening of the bag unit and pressing them by a sealing mold to melt-bond the melt-bonding part of the mouth member to the opening, wherein the temperature of the sealing mold is higher than a melting point of a bag unit resin by 10° C. or more, and time period after the preliminary heating step until the pressing by the sealing mold is 1 to 4 seconds.