Method for producing polyester container

A method for producing a hollow bottle-shaped container of biaxially oriented polyethylene terephthalate having a neck section, a bottom section, and a body section extending between said neck section and bottom section from a preform having a prefinished neck section with an annular radially outwardly extending ledge at its lower end, said method comprising the steps:

• heating only the neck section of said preform, including the ledge, with a radiant heater at 120.degree. C. to 180.degree. C. for 2 minutes 30 seconds-8 minutes and thereafter cooling the neck section to increase the density of the spherulitic texture only in the neck section to produce a preform having a milky color only in the neck section including the ledge and the remainder of the preform being transparent;
• and thereafter
• biaxially orienting in a mold said preform in the regions of the preform below said ledge, including those immediately therebelow with no stretching in the neck section including the ledge to form the hollow-shaped container having a milky color only in the neck section including the ledge and the remainder of the container being transparent.

A method for producing a hollow bottle-shaped container of biaxially oriented polyethylene terephthalate having a neck section, a bottom section, and a body section extending between said neck section and bottom section from a preform having a prefinished neck section with an annular radially outwardly extending ledge at its lower end, said method comprising the steps:

• heating only the neck section of said preform, including the ledge, with a radiant heater at 140.degree. C. to 170.degree. C. for 3-5 minutes and thereafter cooling the neck section to increase the density of the spherulitic texture only in the neck section to produce a preform having a milky color only in the neck section including the ledge and the remainder of the preform being transparent;
• and thereafter
• biaxially orienting in a mold said preform in the regions of the preform below said ledge, including those immediately therebelow with no stretching in the neck section including the ledge to form the hollow-shaped container having a milky color only in the neck section including the ledge and the remainder of the container being transparent.

A method for producing a hollow bottle-shaped container of biaxially oriented polyethylene terephthalate having a neck section, a bottom section, and a body section extending between said neck section and bottom section from a preform having a prefinished neck section with an annular radially outwardly extending ledge at its lower end, said method comprising the steps:

• heating only the neck section, including the ledge, and the bottom section of said preform with a radiant heater at at least the glass transition temperature for at least 2 minutes 30 seconds and thereafter cooling the neck and bottom sections to increase the density of the spherulitic texture in the neck section, including the ledge, and the bottom section to produce a preform having a milky color only in the neck section, including the ledge, and the bottom section and the remainder of the preform being transparent;
• and thereafter
• biaxially orienting in a mold said preform of the container in the regions of the container below the ledge including those immediately therebelow with no stretching in the neck section including the ledge to form the hollow bottle-shaped container having a milky color only in the neck section, including the ledge, and the bottom section and the remainder of the container being transparent.

A method for producing a hollow bottle-shaped container of biaxially oriented polyethylene terephthalate having a neck section, a bottom section, and a body section extending between said neck section and bottom section from a preform having a prefinished neck section with an annular radially outwardly extending ledge at its lower end, said method comprising the steps:

• heating the neck section of said preform, including the ledge, and the bottom section with a radiant heater at 120.degree. C. to 180.degree. C. for 2 minutes 30 seconds-8 minutes and thereafter cooling the neck and bottom sections to increase the density of the spherulitic texture in the neck section, including the ledge, and bottom section to produce a preform having a milky color only in the neck section, including the ledge, and the bottom section and the remainder of the preform being transparent;
• and thereafter
• biaxially orienting in a mold said preform of the container in the regions of the container below the ledge including those immediately therebelow with no stretching in the neck section including the ledge to form the hollow-shaped container having a milky color in the neck section, including the ledge, and the bottom section and the remainder of the container being transparent.

A method for producing a hollow bottle-shaped container of biaxially oriented polyethylene terephthalate having a neck section, a bottom section, and a body section extending between said neck section and bottom section from a preform having a prefinished neck section with an annular radially outwardly extending ledge at its lower end, said method comprising the steps:

• heating the neck section of said preform, including the ledge, and the bottom section with a radiant heater at 140.degree. C. to 170.degree. C. for 3-5 minutes and thereafter cooling the neck and bottom sections to increase the density of the spherulitic texture in the neck section, including the ledge, and the bottom section to produce a preform having a milky color only in the neck section including the ledge, and the bottom section and the remainder of the preform being transparent;
• and thereafter
• biaxially orienting in a mold said preform of the container in the regions of the container below the ledge including those immediately therebelow with no stretching in the neck section including the ledge to form the hollow-shaped container having a milky color in the neck section, including the ledge, and the bottom section and the remainder of the container being transparent.