An assembled preform (1) is provided for the making of a blown container, comprising a first external preform body (10) which comprises a neck part (2) which has an external region (4) which includes a threaded region (5) and an internal surface (3), and a second internal preform (11) which is suitable to be completely contained within said first external preform body (10), said second internal preform (11) having a neck region (12) suitable to cooperate with said neck internal surface (3) of said first external preform (10), the preform being characterized in that said neck region (12) of said second internal preform (11) comprises locking means (13,14) integrally obtained on the material of said second preform (11) and suitable for cooperating by blocked interference with said internal region (3) of the neck part (2) of said external preform (10) when said second internal preform (11) is inserted in said first external preform (10).

A plural preform assembly having nested preforms with an inner preform and an outer preform. The preforms are sealably joined together, defining a volume between the preforms. Propellant is disposed in the volume between the preforms. The preforms are later blow molded to provide a bag in bottle, bottle in bottle or similar container. The propellant charge is already present when blow molded, preventing the need for a later propellant filling step.

A plural preform assembly having nested preforms. The preforms are held together by an interference fit. The interference fit is provided by the friction between the preforms which occurs when the inner preform is inserted into the outer preform. At least one preform may have ribs extending radially towards the other preform. The ribs provided concentricity and interference to hold the preforms together during subsequent operations. The preforms may later be blow molded to provide a bag in bottle or similar container.

A plural preform assembly having nested preforms. The preforms are held together by an interference fit. The interference fit is provided by the friction between the preforms which occurs when the inner preform is inserted into the outer preform. At least one preform may have ribs extending radially towards the other preform. The ribs provided concentricity and interference to hold the preforms together during subsequent operations. The preforms may later be blow molded to provide a bag in bottle or similar container.

A plural preform assembly having nested preforms. The preforms are held together by an interference fit. The interference fit is provided by the friction between the preforms which occurs when the inner preform is inserted into the outer preform. At least one preform may have ribs extending radially towards the other preform. The ribs provided concentricity and interference to hold the preforms together during subsequent operations. The preforms may later be blow molded to provide a bag in bottle or similar container.

A plural preform assembly having nested preforms with an inner preform and an outer preform. The preforms are sealably joined together, defining a volume between the preforms. Propellant is disposed in the volume between the preforms. The preforms are later blow molded to provide a bag in bottle, bottle in bottle or similar container. The propellant charge is already present when blow molded, preventing the need for a later propellant filling step.

A plural preform assembly having nested preforms with an inner preform and an outer preform. The preforms are sealably joined together, defining a volume between the preforms. Propellant is disposed in the volume between the preforms. The preforms are later blow molded to provide a bag in bottle, bottle in bottle or similar container. The propellant charge is already present when blow molded, preventing the need for a later propellant filling step.

A plural preform assembly having nested preforms with an inner preform and an outer preform. The preforms are sealably joined together, defining a volume between the preforms. Propellant is disposed in the volume between the preforms. The preforms are later blow molded to provide a bag in bottle, bottle in bottle or similar container. The propellant charge is already present when blow molded, preventing the need for a later propellant filling step.

A plural preform assembly having nested preforms. The preforms are held together by an interference fit. The interference fit is provided by the friction between the preforms which occurs when the inner preform is inserted into the outer preform. At least one preform may have ribs extending radially towards the other preform. The ribs provided concentricity and interference to hold the preforms together during subsequent operations. The preforms may later be blow molded to provide a bag in bottle or similar container.