초록 ▼

This invention relates to a method of fabricating a bottle-shaped container of saturated polyester having superior mechanical strength, very low degrees of age and high temperature deformation, and superior dimensional stability. The piece for forming the bottle-shaped container is heated to an orie

This invention relates to a method of fabricating a bottle-shaped container of saturated polyester having superior mechanical strength, very low degrees of age and high temperature deformation, and superior dimensional stability. The piece for forming the bottle-shaped container is heated to an orientation temperature, is biaxially oriented in a blowing mold and is then thermally set by maintaining the outer wall surface of the expanded container in contact with the inner wall surface of the mold, which is kept at a temperature in the range between the glass transition point and the crystallization temperature, for longer than 5 seconds. The blowing mold is formed with the size adjusted in capacity by approx. 6% to allow for shrinkage of the product container when the container is exposed to a high temperature greater than 70°C. and then left to stand, so as to thereby obtain a container of accurate capacity.

대표청구항 ▼

A method of fabricating a bottle-shaped container of saturated polyester from a preformed cylindrical piece of polyethylene terephthalate with a bottom, comprising: heating the piece to a temperature for orienting, loading the heated piece into the blowing mold which is heated at a temperature in th

A method of fabricating a bottle-shaped container of saturated polyester from a preformed cylindrical piece of polyethylene terephthalate with a bottom, comprising: heating the piece to a temperature for orienting, loading the heated piece into the blowing mold which is heated at a temperature in the range between the glass transition temperature and the orientation temperature of the saturated polyester, biaxially orienting the piece by longitudinally orienting the piece and then laterally orienting it by introducing compressed air into the interior of the piece while said piece is contained in the mold until the outer wall of the piece comes into contact with the inner wall of the mold; the container expanded by said biaxially orienting step being thermally set by said contact with the outer wall of the container with the inner wall of the mold retained at a temperature in the range between substantially the glass transition temperature and the orientation temperature for a period of time in the range of six to eight seconds; opening the mold to unload and rapidly cool the container thus molded; said mold having a capacity upwardly adjusted by about 6% relative to the desired final capacity of said container, said blowing mold temperature being in the range of about 70°C. to less than about 80°C.