Patents by Inventor Suppayan M. Krishnakumar

Suppayan M. Krishnakumar has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5976653
    Abstract: A multilayer preform and container, and method of forming the same, having at least one layer including polyethylene naphthalate (PEN) to provide enhanced oxygen barrier performance and thermal stability. The PEN layer may be a homopolymer, copolymer, or blend of PEN. In a first high-PEN embodiment, the exterior layer contains on the order of 80-100% PEN and 0-20% PET by total weight of the layer, and a core layer of a non-strain hardenable polyester such as PETG. In a second low-PEN embodiment, the exterior layer includes a strain hardenable low-PEN copolymer or blend including on the order of 1-20% PEN and 80-99% PET, and the core layer is a strain-hardenable polyester such as a low-copolymer PET. In a third mid-range PEN embodiment, the exterior wall includes a substantially amorphous PEN copolymer or blend containing on the order of 20-80% PEN and 80-20% of another polyester such as PET, and a strain-hardened core layer of polyester such as a low-copolymer PET.
    Type: Grant
    Filed: April 8, 1997
    Date of Patent: November 2, 1999
    Assignee: Continental PET Technologies, Inc.
    Inventors: Wayne N. Collette, Steven L. Schmidt, Suppayan M. Krishnakumar
  • Patent number: 5971184
    Abstract: A hot-fillable plastic container having a panel section of a size suitable for gripping the container in one hand. The panel section includes two opposing vertically-elongated and radially-indented vacuum panels, and two opposing horizontally-disposed and radially-indented finger grips. Each vacuum panel preferably has an invertible central wall portion movable from a convex first position prior to hot-filling of the container, to a concave second position under vacuum pressure following hot-filling and sealing of the container.
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: October 26, 1999
    Assignee: Continental PET Technologies, Inc.
    Inventors: Suppayan M. Krishnakumar, Wayne N. Collette, David Piccioli
  • Patent number: 5952066
    Abstract: A substantially transparent package or preform made of a polymer composition including an aliphatic polyketone as an oxygen scavenger having the formula ##STR1## where n is the number of repeating units and R is hydrogen, an organic side chain, or a silicon side chain. The aliphatic polyketone may be advantageously combined with other thermoplastic polymers to provide the desired injection molding and stretch blow molding characteristics for making substantially amorphous injection molded preforms and substantially transparent biaxially oriented polyester containers. A multilayer container package may be provided having a core layer of the oxygen scavenging composition, and inner and outer layers of polyethylene terephthalate (PET). The container may further include layers of a high-oxygen barrier polymer such as ethylene vinyl alcohol (EVOH).
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: September 14, 1999
    Assignee: Continental PET Technologies, Inc.
    Inventors: Steven L. Schmidt, Wayne N. Collette, Ernest A. Coleman, Suppayan M. Krishnakumar
  • Patent number: 5908128
    Abstract: A pasteurizable plastic container having movable panels to alleviate internal pressure changes during pasteurization in order to avoid uncontrolled permanent deformation of the container body. As molded, each panel has a shallow recessed central wall which during the increased temperature and pressurization of pasteurization, moves outwardly to alleviate at least part of the internal pressure. During cooling, the panels move back inwardly to alleviate at least part of the negative pressure. The container may further include hoop ribs in the land areas above and below the panels, an axially elongatable hoop rib in an upper shoulder section, and an angled heel portion adjacent the standing ring. These additional elements further restrict uncontrolled bulging of the post walls, which would lead to improper label application and/or excessive volume change.
    Type: Grant
    Filed: July 17, 1995
    Date of Patent: June 1, 1999
    Assignee: Continental PET Technologies, Inc.
    Inventors: Suppayan M. Krishnakumar, Wayne N. Collette, David Piccioli
  • Patent number: 5884792
    Abstract: This relates to the packaging of a hot liquid product in a container having little resistance to internal vacuum wherein immediately after the container has been filled, the container is internally pressurized and closed. This particularly relates to an injection molded preform formed of a suitable polyester resin which is of a configuration related to an intended blow mold cavity whereby the desired biaxial orientation is obtained in the various portions of the resultant container and the wall thickness of the container base is increased so as to prevent undue stress enlargement and creep at high internal pressurization. Internal pressurization on the order of 40-45 psig is envisioned.
    Type: Grant
    Filed: April 12, 1993
    Date of Patent: March 23, 1999
    Assignee: Continental PET Technologies, Inc.
    Inventors: Suppayan M. Krishnakumar, Wayne N. Collette, Thomas E. Nahill
  • Patent number: 5853829
    Abstract: This relates to a returnable/refillable container in the form of a blow molded polyester biaxially oriented bottle wherein the container includes a domed base construction wherein the wall thickness gradually and smoothly increases to a maximum at the center of the dome. This also relates to a specially configurated preform which is blow molded to form the container and a specially configurated blow mold cavity for receiving a preform having a lower axial projection in the fore of an elongated gate without crushing.
    Type: Grant
    Filed: January 29, 1997
    Date of Patent: December 29, 1998
    Assignee: Continental PET Technologies, Inc.
    Inventors: Suppayan M. Krishnakumar, Wayne N. Collette, Thomas E. Nahill
  • Patent number: 5829614
    Abstract: 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.
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: November 3, 1998
    Assignee: Continental Pet Technologies, Inc.
    Inventors: Wayne N. Collette, Suppayan M. Krishnakumar, Chi Ching Lin
  • Patent number: 5804016
    Abstract: 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.
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: September 8, 1998
    Assignee: Continental PET Technologies, Inc.
    Inventors: Steven L. Schmidt, Suppayan M. Krishnakumar, Wayne N. Collette
  • Patent number: 5759656
    Abstract: A method of forming a multi-layer polyester preform and container, particularly suitable for refillable PET carbonated beverage bottles, having an interior layer of high copolymer polyester material which resists hazing in the preform injection stage, and at least one exterior layer of a polyester to achieve enhanced strain-induced crystallization in the exterior layer during blow molding. The container can withstand higher caustic wash temperatures and exhibits reduced flavor carryover from one product to another.
    Type: Grant
    Filed: May 19, 1997
    Date of Patent: June 2, 1998
    Assignee: Continental PET Technologies, Inc.
    Inventors: Wayne N. Collette, Steven L. Schmidt, Suppayan M. Krishnakumar
  • Patent number: 5728347
    Abstract: A method of forming a multi-layer polyester preform and container, particularly suitable for refillable PET carbonated beverage bottles, having an interior layer of high copolymer polyester material which resists hazing in the preform injection stage, and at least one exterior layer of a polyester to achieve enhanced strain-induced crystallization iin the exterior layer during blow molding. The container can withstand higher caustic wash temperatures and exhibits reduced flavor carryover from one product to another.
    Type: Grant
    Filed: March 31, 1995
    Date of Patent: March 17, 1998
    Assignee: Continental PET Technologies, Inc.
    Inventors: Wayne N. Collette, Steven L. Schmidt, Suppayan M. Krishnakumar
  • Patent number: 5704503
    Abstract: A panel design for a hot-fillable plastic container has a tall and slender panel section. The panel configuration provides increased resistance to longitudinal bending and hoop failure, yet provides good hoop flexibility to maximize vacuum panel movement. The panel section has a substantially cylindrical circumference with a plurality of vacuum panels symmetrically disposed about the panel circumference, post walls between the vacuum panels, and land areas above and below the vacuum panels. The ratio of vacuum panel height D to panel diameter C is on the order of 0.85 to 1.05. Longitudinal post ribs are provided in the post walls. The land areas above and below the vacuum panels are of a height E greater than on the order of 0.45 inch, and the ratio of the land area height E to panel diameter C is on the order of greater than 0.1. Circumferential hoop ribs are provided in the land areas to prevent ovalization and hoop collapse.
    Type: Grant
    Filed: October 28, 1994
    Date of Patent: January 6, 1998
    Assignee: Continental PET Technologies, Inc.
    Inventors: Suppayan M. Krishnakumar, Wayne N. Collette
  • Patent number: 5637167
    Abstract: A method for post-mold attachment of a handle to a strain-oriented plastic container body. The method utilizes thermal shrinkage of the oriented container body to engage the handle; for example, a highly-oriented recess is molded in the container body and then shrunk to engage a complimentary-shaped lug on the handle. The method is useful for both hot-fillable and pasteurizable containers, and is particularly useful for making larger-sized containers, wherein the weight of the product and size of the container make handling and pouring difficult.
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: June 10, 1997
    Assignee: Continental PET Technologies, Inc.
    Inventors: Suppayan M. Krishnakumar, Wayne N. Collette, David Piccioli
  • Patent number: 5628957
    Abstract: A multilayer preform and container, and method of forming the same, having at least one layer including polyethylene naphthalate (PEN) to provide enhanced oxygen barrier performance and thermal stability. The PEN layer may be a homopolymer, copolymer, or blend of PEN. In a first high-PEN embodiment, the exterior layer contains on the order of 80-100% PEN and 0-20% PET by total weight of the layer, and a core layer of a non-strain hardenable polyester such as PETG. In a second low-PEN embodiment, the exterior layer includes a strain hardenable low-PEN copolymer or blend including on the order of 1-20% PEN and 80-99% PET, and the core layer is a strain-hardenable polyester such as a low-copolymer PET. In a third mid-range PEN embodiment, the exterior wall includes a substantially amorphous PEN copolymer or blend containing on the order of 20-80% PEN and 80-20% of another polyester such as PET, and a strain-hardened core layer of polyester such as a low-copolymer PET.
    Type: Grant
    Filed: December 5, 1994
    Date of Patent: May 13, 1997
    Assignee: Continental PET Technologies, Inc.
    Inventors: Wayne N. Collette, Steven L. Schmidt, Suppayan M. Krishnakumar
  • Patent number: 5622735
    Abstract: 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.
    Type: Grant
    Filed: September 7, 1995
    Date of Patent: April 22, 1997
    Assignee: Continental PET Technologies, Inc.
    Inventors: Suppayan M. Krishnakumar, Wayne N. Collette, Nikhil Mani
  • Patent number: 5599496
    Abstract: Method of making a refillable polyester container having a low orientation base with improved resistance to caustic wash cracking. The method includes providing a preform with an upper base-forming thickened portion which resists axial elongation (thereby increasing the orientation of the body) and a lower base-forming tapered portion which decreases in thickness so as to gradually reduce the wall thickness of a central dome in the container base. The bottom of the preform base includes a central thickened region which is maintained in a recess during blowing to insure centering and prevent the formation of stress concentrations.
    Type: Grant
    Filed: September 27, 1994
    Date of Patent: February 4, 1997
    Assignee: Continental PET Technologies, Inc.
    Inventors: Suppayan M. Krishnakumar, Wayne N. Collette, Thomas E. Nahill
  • Patent number: 5582788
    Abstract: Method of making multilayer preforms which resist delamination and in a reduced cycle time. A first array of preforms are molded onto a first array of cores in an associated array of mold cavities, the cores and preforms are removed from the mold cavities as soon as possible without significant physical preform deformation, and the preforms are then cooled on the cores while a second array of cores is positioned in the mold cavities. Cooling on the cores prevents delamination of the preform layers and reduces the in-mold cooling time. Providing multiple sets of cores on a rotating turret further reduces the cycle time compared to the prior art use of robotic cooling tubes.
    Type: Grant
    Filed: December 28, 1994
    Date of Patent: December 10, 1996
    Assignee: Continental PET Technologies, Inc.
    Inventors: Wayne N. Collette, Thomas E. Nahill, Suppayan M. Krishnakumar
  • Patent number: 5533881
    Abstract: An apparatus for making a blow-molded container from a strain-hardenable polymer, the container having deep recesses for secure "post mold" attachment of a handle. The container is formed in a modified blow mold having retractable blades. The blades are partially extended for blow molding partial recesses, and then further extended for mechanically forming the deep handle recesses. The mechanical forming operation overcomes the stretch limits imposed by strain-hardening of the plastic material during blow molding, and the "post-mold" attachment of the handle provides a reduced cycle time and lower level of defects compared to the known "in-mold" handle forming operations.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: July 9, 1996
    Assignee: Continental PET Technologies, Inc.
    Inventors: Wayne N. Collette, Suppayan M. Krishnakumar
  • Patent number: 5520877
    Abstract: 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.
    Type: Grant
    Filed: June 30, 1993
    Date of Patent: May 28, 1996
    Assignee: Continental PET Technologies, Inc.
    Inventors: Wayne N. Collette, Suppayan M. Krishnakumar, Chi C. Lin
  • Patent number: D382485
    Type: Grant
    Filed: April 21, 1993
    Date of Patent: August 19, 1997
    Assignee: Continental PET Technologies, Inc.
    Inventors: Suppayan M. Krishnakumar, Wayne N. Collette
  • Patent number: D385497
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: October 28, 1997
    Assignee: Continental PET Technologies, Inc.
    Inventors: Suppayan M. Krishnakumar, Wayne N. Collette