Kortec, Inc.

Milacron Inc.

Husky Injection Molding Systems Limited

Dynisco, Inc.

Dynisco Hotrunners, Inc.

Paul Michael Swenson

Douglas Grosvenor Sabin

Adrienne Murphy Jalbert

Christopher W Lee

Ronald Roberts

Michael Lewis Vasapoli

William J Hume

Jeffrey Douglas MacDonald

Adrienne Murphy Clark

Adam Craig Reynolds

John Nicholas Kermet

Douglas G Sabin

Methods and systems for co-injection molding multilayer articles having one or more molded apertures disposed between a gate region and a peripheral region of the article are disclosed. The articles include an interior layer disposed between an inner layer and an outer layer. An article has interior layer coverage over at least 98% of a perimeter of a cross-section of the article downstream of the one or more molded apertures. A method includes modifying fluid flowing past an aperture-forming region of a mold cavity to compensate for the drag of the aperture-forming region on the velocity of the fluid flowing proximal to the aperture-forming region.

Co-injection molded multi-layer article with injection-formed aperture between gate area and peripheral edge

Methods and systems for co-extruding multiple polymeric material flow streams into a mold cavity to produce a molded plastic article having an injection-formed aperture in gate region of the article are disclosed herein. A method includes providing a valve pin having a distal portion with a first diameter and a mid-portion with a second diameter smaller than the first diameter and providing a mold defining a cavity corresponding to a shape of a resulting molded plastic article. The mold has a recess aligned with a gate region of the mold, extending into the mold and configured to receive the distal portion of the valve pin when the distal portion of the valve pin extends beyond the gate region. The method includes advancing the distal portion of the valve pin into the recess until the mid-portion of the valve pin at least partially extends into the gate region, thereby establishing a flow path for a combined polymeric stream into the cavity at the gate region for forming a molded plastic article having at least one layer of a first polymeric material and at least one layer of a second polymeric material. The method also includes withdrawing the mid-portion of the valve pin from the gate region, thereby forming an injection-molded aperture in the resulting molded plastic article at the gate region.

Techniques to mold parts with injection-formed aperture in gate area

Container

Plastic container (), including a side wall () and a flexible portion () of a base (). The flexible portion of the base deflects when the sealed plastic container experiences a differential pressure. The deflection of the flexible portion of the base acts to change the internal volume of the container and thereby reduce the differential pressure. The container is a retortable container. The container may be injection-molded with inner and outer plastic layers () and a core layer () between the inner and outer plastic layers.

Plastic container with flexible base portion

Disclosed herein are methods and systems for co-extruding multiple polymeric material flow streams into a mold cavity to produce a molded plastic article. At least one interior core stream of a first polymeric material is surrounded by inner and outer streams of at least one other polymeric material. The interior core stream serves as an interior layer of a resultant molded plastic article while the inner and outer streams serve as inner and outer layers, respectively, of the resultant plastic article. The interior core stream is selectively directed to flow into or past a downstream branch channel in a mold cavity. The downstream branch channel branches from a primary channel in the mold cavity at a branch junction. The branch channel defines a protrusion portion of the resultant molded plastic article. The leading edge of the interior core stream is selectively controlled in the branch channel to position the leading edge at or near to the terminal end of the branch channel without having the leading edge of the interior core stream breakthrough a flow-front of the inner and outer streams. The resultant molded plastic article includes an interior layer formed of the first polymeric material that extends into, through and to a distal end of the protrusion while still being encased by inner and outer layers formed from the inner and outer flow streams.

Methods of molding multi-layer polymeric articles having control over the breakthrough of the core layer

Disclosed herein are methods and systems for the preparation of a co-injection molded multilayer plastic article. Some methods include co-extruding a combined polymeric stream having an interior core stream encased by an inner stream and an outer stream. One or more pulses in a thickness of the interior core stream create portions of an edge of the outer flow stream flowing along different streamlines. A first portion of an outer edge of the interior core stream flows beyond a second portion of the outer edge thereby forming one or more cohesion members that physically interlock the interior layer with the inner layer, with the outer layer or with both. Some embodiments reduce or eliminate a need for addition of an adhesive in the composite stream to prevent delamination of layers of the resulting multilayer plastic article. In some embodiments, cohesion members may be employed to produce a desired cosmetic effect in a resulting article.

Methods and systems for the preparation of molded plastic articles having a structural barrier layer

A co-injected molded multi-layer article has inner and outer layers, an interior layer contained within the inner and outer layers and a surface portion to which a closure or other component may be heat-sealed. The article is molded by co-injecting the inner, outer and interior layer materials into a mold cavity of a mold. The interior layer material is caused to flow along a steam line offset from the zero velocity gradient of the combined material flow and biased toward a material flow for forming an outer wall of the multi-layer article. The resultant molded multi-layer article contains an interior layer located in a heat sealable region that avoids a breach or failure during a heat seal operation to seal an opening of the molded article.

Heat-seal failure prevention apparatus

A mold for molding an injection molded article comprises a mold cavity with a non-symmetrical portion. At least one flow leader in the non-symmetrical portion of the cavity produces a symmetrical flow boundary in a multilayer flow downstream of the non-symmetrical portion of the mold cavity. The at least one flow leader may be a variable thickness flow leader or may alternatively be a plurality of flow leaders having a flow path length that differs from the flow path length of an adjacent flow leader by no more than about 15%. The multilayer flow comprising an inner layer, an outer layer, and an interior layer. Co-injection molding apparatus and methods that may use the foregoing mold are disclosed. Similarly, co-injection molded articles and containers that may result from the foregoing mold, apparatus, and methods are disclosed.

Non-symmetric multiple layer injection molded products and methods

A molded multi-layer article has an interior layer contained within inner and outer layers. The article is molded by co-injecting the inner, outer, and interior layer materials into a mold defining a cavity. The interior layer material is caused to flow along a steam line offset from the zero velocity gradient of the combined material flow in a manner so that the interior layer material flow stream does not flow along or cross the zero velocity gradient yet has a greater flow velocity than the average flow velocity of the combined flow front. These methods and apparatus can mold four or more multilayer articles at once, each having an interior layer extending throughout 95% or more of the sealable portion of the article. The interior layer of a resultant article can extend throughout 99% or more of the sealable portion of the article.

Method of molding a multi-layer article

A mold for molding an injection molded article comprises a mold cavity with a non-symmetrical portion. At least one flow leader in the non-symmetrical portion of the cavity may produce a symmetrical flow boundary in a multilayer flow downstream of the non-symmetrical portion of the mold cavity. The at least one flow leader may be a variable thickness flow leader. The multilayer flow comprising an inner layer, an outer layer, and an interior layer. Co-injection molding apparatus and methods that may use the foregoing mold are disclosed. Similarly, co-injection molded articles and containers that may result from the foregoing mold, apparatus, and methods are disclosed.

Growing community of inventors

South Hamilton, MA, United States of America

Paul Michael Swenson