摘要:
A method and apparatus for forming a plastic container having an enhanced level of crystallinity for improved thermal stability. A substantially amorphous and transparent preform in the molecular orientation temperature range is expanded by a pulse-blow process one or more times to form an intermediate article, prior to a final expansion step to the full container dimensions. The pulse-blow step is conducted at a relatively high-strain rate to maximize the formation of crystal nucleation sites, followed by deflation to relax the amorphous orientation, and the final expansion step is conducted at a low-strain rate to minimize the amorphous orientation. The resulting container has a higher thermal deformation temperature and reduced thermal shrinkage and is particularly adapted for use as a refillable or hot-fill beverage container. A blow-mold and fluid supply apparatus is provided, including a metering chamber and piston, for alternatively supplying the high and low-strain rate inflations.
摘要:
A method of making a polyester container having an enhanced level of crystallinity in the sidewall while maintaining a low level of crystallinity in a thickened base portion. The container is particularly useful as a refillable container which can withstand higher caustic wash temperatures and exhibits reduced flavor carryover, or as a hot-fill container. According to the method, a sidewall-forming section of a preform is initially expanded, heated to contract and crystallize the same, and than reexpanded; a base-forming portion of the preform is shielded from the heat treatment and is expanded either before or after the heat treatment step.
摘要:
A stretch-blow-molded container obtained by biaxially stretching and blow-molding a thermoplastic polyester and which exhibits heat resistance or heat resistance and pressure resistance to withstand sterilization by heating at the time of hot filling. The stretch-blow-molded container is obtained by stretch-blow-molding a preform formed of a thermoplastic polyester as a chief component, wherein the body portion, bottom portion and shoulder portion are stretch-oriented, and at least the central portion in the bottom has an endothermic peak (B) due to the extinction of pseudo crystals in a temperature region higher than a glass transition point of the polyester but lower than a temperature at which the crystals of the polyester start melting as measured by using a differential scanning calorimeter (DSC).
摘要:
A multilayer plastic container having enhanced strength for high temperature and pressure applications such as the pasteurization of carbonated juice drinks. The container is commercially cost-effective in comparison to prior art pasteurizable glass containers, and provides all of the advantages of plastic over glass, i.e., lightweight, shatter-resistant, etc. In a particular embodiment, the multilayer container includes inner and outer layers of a relatively high IV virgin PET, e.g., 0.85-0.90 dl/g, and a core layer of post-consumer PET having a substantially lower IV. The container has a relatively tall and slender profile, with high orientation levels in the panel and shoulder, and an oriented thick-walled base with feet. The base preferably has a high profile and angled foot pads which are allowed to move outwardly under creep. According to a method of making a multilayer preform for such container, an enhanced injection rate and mold pressure are utilized to enhance interlayer bonding and prevent separation of the layers in spite of their substantial differences in IV.
摘要:
A method of making a polyester container having an enhanced level of crystallinity in the sidewall while maintaining a low level of crystallinity in a thickened base portion. The container is particularly useful as a refillable container which can withstand higher caustic wash temperatures and exhibits reduced flavor carryover, or as a hot-fill container. According to the method, a sidewall-forming section of a preform is initially expanded, heated to contract and crystallize the same, and than reexpanded; a base-forming portion of the preform is shielded from the heat treatment and is expanded either before or after the heat treatment step.
摘要:
A method of making a polyester container having an enhanced level of crystallinity in the sidewall while maintaining a low level of crystallinity in a thickened base portion. The container is particularly useful as a refillable container which can withstand higher caustic wash temperatures and exhibits reduced flavor carryover, or as a hot-fill container. According to the method, a sidewall-forming section of a preform is initially expanded, heated to contract and crystallize the same, and than reexpanded; a base-forming portion of the preform is shielded from the heat treatment and is expanded either before or after the heat treatment step.
摘要:
A multilayer plastic container having enhanced strength for high temperature and pressure applications such as the pasteurization of carbonated juice drinks. The container is commercially cost-effective in comparison to prior art pasteurizable glass containers, and provides all of the advantages of plastic over glass, i.e., lightweight, shatter-resistant, etc. In a particular embodiment, the multilayer container includes inner and outer layers of a relatively high IV virgin PET, e.g., 0.85-0.90 dl/g, and a core layer of post-consumer PET having a substantially lower IV. The container has a relatively tall and slender profile, with high orientation levels in the panel and shoulder, and an oriented thick-walled base with feet. The base preferably has a high profile and angled foot pads which are allowed to move outwardly under creep. According to a method of making a multilayer preform for such container, an enhanced injection rate and mold pressure are utilized to enhance interlayer bonding and prevent separation of the layers in spite of their substantial differences in IV.
摘要:
A fluid supply apparatus for a blow mold, which includes a control valve having multiple positions for alternatively supplying fluid to the blow mold from a fluid supply and a metering chamber. The control valve has a further position configured to fill the metering chamber with fluid, and empty the blow mold chamber into an exhaust conduit. The apparatus is useful for performing pulse blow inflations at a high-strain rate in order to increase the crystallinity level in the body of a container.
摘要:
The invention relates to an element of a thermoplastic of the polyester or polyamide type, and preferably of polyethylene terephthalate, the element consisting of an edge part which surrounds a body in an arrangement in which the latter is sunk relative to the edge part. The element is formed from a blank of mainly amorphous material or from a material having a crystallinity of less than 10%, the blank being, for example, a flat plate, a blank shell or the like. The body or parts thereof are shaped by stretching the blank until that material which is located within the material sections of the blank flows to from the edge part in the element, the material stretched to flowing in the body assuming a crystallinity of between 10 and 25%, while the crystallinity in the material in the edge part and in the unstretched parts retaining its original value of less than 10%. There is also disclosed a process and equipment for manufacturing the element.