Polymeric replacement for a glass drinking container

Abstract

A polymeric replacement vessel, or container, for glassware and glass containers and a method of making the same. polymeric drinking container simulates a glass drinking container having a glass drinking container volume. The polymeric drinking container comprises a base and an enclosed wall composed of the polymer. The wall is formed with the base and extends from the base while defining an opening opposite the base. The enclosed wall includes an inside surface and an outside surface. The base and enclosed wall form a polymeric drinking container volume made of the polymeric material. This polymeric drinking container volume is equal to the glass component drinking container volume plus an amount equal to the glass component drinking container volume multiplied times the ratio of the specific gravity of the glass to the specific gravity of the polymer.

Claims

1. A method of manufacturing a polymeric drinking container, comprising providing a core layer constructed of a first polymeric material; inserting the first core into a cavity; applying at least one over molded layer constructed of a second polymeric material to the core layer; cooling the at least one over molded layer and the core layer; inserting the cooled layers into an incrementally larger cavity; and applying at least one additional over molded layer constructed of a third polymeric material to the applied at least one over molded layer; providing a mold for molding a molten thermoplastic polymer into a drinking container, the mold having at least two separable mold portions adjoined along a seam, the adjoined mold portions forming mold walls and a mold core that define a mold cavity; providing a plurality of first cooling lines adjacent to the mold walls and the seam and a plurality of second cooling lines adjacent to the mold walls but separated from the seam by at least one of the plurality of first cooling lines; cooling the plurality of first cooling lines to a first temperature and cooling the plurality of second cooling lines to a second temperature, wherein the first temperature is lower than the second temperature; injecting molten thermoplastic polymer into the cavity; and cooling the molten thermoplastic polymer to form the core layer of polymeric material.

2. The method of claim 1, wherein at least one of the first polymeric material, the second polymeric material, and the third polymeric material is a clear engineering thermoplastic.

3. The method of claim 2, wherein at least one of the first polymeric material, the second polymeric material, and the third polymeric material is chosen from polyethylene terephthalate, polyethylene terephthalate glycol, styrene acrylonitrile, polycarbonate, polymethylpentene, and polyvinylchloride.

4. The method of claim 3, wherein at least one of the first polymeric material, the second polymeric material, and the third polymeric material is chosen from polypropylene, polyethylene, polyethylene terephthalate, and polyvinylchloride and further includes at least one additive chosen from calcium carbonate, talc, aluminum silicate.

5. A method of manufacturing a polymeric drinking container, the method comprising: providing a mold for molding a molten thermoplastic polymer into a drinking container, the mold having at least two separable mold portions adjoined along a seam, the adjoined mold portions forming mold walls and a mold core that define a mold cavity; providing a plurality of first cooling lines adjacent to the mold walls and the seam and a plurality of second cooling lines adjacent to the mold walls but separated from the seam by at least one of the plurality of first cooling lines; cooling the plurality of first cooling lines to a first temperature and cooling the plurality of second cooling lines to a second temperature, wherein the first temperature is lower than the second temperature; injecting molten thermoplastic polymer into the cavity.

6. The method of claim 5, wherein the thermoplastic polymer is a clear engineering thermoplastic when solid.

7. The method of claim 6, wherein the thermoplastic polymer is chosen from polyethylene terephthalate, polyethylene terephthalate glycol, styrene acrylonitrile, polycarbonate, polymethylpentene, and polyvinylchloride.

8. The method of claim 6, wherein the thermoplastic polymer is chosen from polypropylene, polyethylene, polyethylene terephthalate, and polyvinylchloride and further includes at least one additive chosen from calcium carbonate, talc, aluminum silicate.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) FIG. 1A is a top perspective view of a polymeric container made in accordance with the current disclosure.

(2) FIG. 1B is a view similar to FIG. 1A showing a relation of the internal volume within the container.

(3) FIG. 1C is a side view of a container as shown in FIGS. 1A-1B.

(4) FIG. 1D is a cross sectional view taken along Line AA in FIG. 1C.

(5) FIG. 2 is a partial cutaway illustration of polymeric containers made in accordance with the current disclosure in a stacked relationship.

(6) FIG. 3A is a side view of an alternate polymeric container made in accordance with the current disclosure.

(7) FIG. 3B is a side view similar to FIG. 3A showing the internal volume of the polymeric container.

(8) FIG. 3C is a top view of the container shown in FIG. 3A.

(9) FIG. 3D is a bottom view of the container shown in FIG. 3A.

(10) FIG. 4A is a top perspective view of an alternate polymeric container made in accordance with the current disclosure.

(11) FIG. 4B is a side view of the container shown in FIG. 4A.

(12) FIG. 4C is a top view of the container shown in FIG. 4B.

(13) FIG. 4D is a cross sectional view along Line A-A in FIG. 4B.

(14) FIG. 5A is a side view of an alternate container made in accordance with the current disclosure.

(15) FIG. 5B is a cross sectional view taken along Line B-B of FIG. 5A.

(16) FIG. 6A is a top perspective view of a polymeric container made in accordance with the current disclosure.

(17) FIG. 6B is a side view of the container shown in FIG. 6A.

(18) FIG. 6C is a cross sectional view taken along Line A-A of FIG. 6B.

(19) FIG. 6D is a side view of the container shown in 6A shown in a stacked relationship.

(20) FIG. 7 is a schematic view of a mold showing a process of making a polymeric container in accordance with the current disclosure.

DETAILED DESCRIPTION OF THE INVENTION

(21) Referring generally now to the Figures, a polymeric container can be shown and generally illustrated by the numeral 10. The container includes a base 12 and an enclosed wall 14. The enclosed wall 14 can be formed with the base 12 and extends from the base 12 and defines an opening 16, or a mouth 16, opposite the base 12. The wall includes an inside surface 18 and an outside surface 20.

(22) The polymeric material is preferably a thermoplastic and can be a clear engineering thermoplastic or a filled engineering thermoplastic. For example a clear engineering thermoplastic can include PET, PETG, SAN, PC, TPX, PVC, and the like. The filled engineering thermoplastics can be thermoplastics, such as can be polypropylene, polyethylene, PET, PVC, and the like, filled with additives such as Mica, Calcium Carbonate, Talc, Aluminum Silicate, and the like. Either of these thermoplastics can be the molded compounds used to form the container structures and base. Further, the base can be intricately molded with a heavy walled streamlined configuration. This facilitates the elimination of voids during the melting and formation processing, including the cooling of the base during the manufacture. Alternately, the base can be intricately molded around an insert or filler that is suitably sized and shaped to provide part of the weight of the base.

(23) The polymeric container 10 is preferably a drinking container, or drinkware, as used to hold a liquid for consumption by a user. The polymeric container 10 is designed to simulate a glass container and provide a similar user experience as the glass container without having various drawbacks of that glass container. Given the variations and the properties of glass and polymers, alterations in the polymeric container design are used to provide that same user experience as the glass container.

(24) For example, the polymeric drinking container as composed of the base and enclosed wall, has a polymeric drinking container volume of the polymeric material that simulates the drinking glass container volume for which it replaces. This polymeric drinking container volume is approximately equal to the glass drinking container volume plus the added volume of polymer material needed to achieve the approximate equivalent weight of the glass container in the polymeric container. This added volume is approximately equal to the volume of the glass, which is the external volume of the glass container minus the internal volume of the glass container, multiplied times the ratio of specific gravity of the glass to the specific gravity of the polymer chosen.

(25) Table 1 includes a listing of specific gravities of some polymers that could be used to create the polymeric drinking container as disclosed. The volume of polymeric material used to create a polymeric drinking container made in accordance with the current disclosure can be configured based upon the specific gravity ratio of the glass of the container of which is replaced, typically soda lime glass, in relation to the specific gravity of the polymer/thermoplastics chosen for the polymeric container.

(26) In a preferred embodiment this volume of polymeric material is configured such that the weight of the polymeric container almost exactly equals the weight of the glass container being replaced. In actuality though, experiments have shown that a different volume of added polymeric material that is actually used (V.sub.PA) will work, give more than satisfactory results, and maintain both functionality and economic viability. This range of V.sub.PA can be expressed as a percentage amount of the ideal volume of polymeric material used added to the initial starting volume to create the desired polymeric container.

(27) The starting point to establish the ideal volume for the polymeric replacement container (V.sub.PE) begins with the volume of the glass container that is to be replaced. This volume can be expressed as the volume of glass of the container (V.sub.G) which equals the external volume of glass (EV.sub.G) minus the internal volume of glass (IV.sub.G). With this as the starting volume, the amount added to the composition of the polymeric container in order to establish a comparable weight between the polymeric container and the glass container can be explained as follows. The polymeric materials are typically less dense than the glass used in conventional glass containers. As such, an additional volume of the polymeric material is required to establish the same weight feeling in the polymeric container to satisfy the end user of the polymeric container when that end user is used to and comfortable with the glass container. This additional added volume can be described as the added volume of polymeric material needed to achieve an equivalent weight feeling in the container in comparison to a glass container (V.sub.PE). This amount of ideal added polymeric material to create the equivalent weight of the glass container in the polymeric container can equal the volume of glass (V.sub.G) in the original glass container multiplied times the ratio of the specific gravity of the glass to the specific gravity of the polymer.

(28) It has been discovered that the exact equivalent is not necessary as such a range of volume actually added is preferred and within the scope of this disclosure. This volume range can be expressed in a range, or percentage of the ideal volume of polymer to be added (V.sub.PE). For example, one range of acceptable (V.sub.PA) includes 0.7 to 1.3 of the (V.sub.PE). Preferably this range is 0.8 to 1.2 (V.sub.PE) and more preferably 0.9 to 1.1 (V.sub.PE). In a more preferred embodiment the percentage of actual volume of the polymeric material added (V.sub.PA) is actually less than the ideal amount of polymer used to equate the weight to the glass (V.sub.PE). In this embodiment, there are ranges that are preferred including a range of 0.7 to 1.0 V.sub.PE, and preferably 0.8 to 1.0 V.sub.PE. In a most preferred embodiment, the value of V.sub.PA is between 0.81 and 1.0 V.sub.PE.

(29) Another feature of a polymeric container made in accordance with the current disclosure is the overall aesthetic feel and look as used by the consumer to partake of the liquid stored therein. It has been discovered that an adherence to a dimension ratio helps facilitate this aesthetic look and feel to the user. Since the overall volume of the polymeric container is increased in comparison to the glass container, an adjustment in the ratios of the diameter and length of the polymeric container are required. As such, a polymeric drinking container has increased dimensions in both diameter and length in comparison to the glass container to which it replaces. The adherence to the comparison ratios in diameters and length of the polymeric container with respect to the glass container maintains an overall dimensional feel and look in the polymeric container that is appeasing to the end user.

(30) For example, the percentage increase of additional polymer with respect to the external volume of the glass container that is replaced can be indicated by V.sub.P+. This number can be calculated by taking the volume of added polymer actually used (V.sub.PA) and subtracting out the volume of the glass container that is replaced (V.sub.G) and dividing that sum by the external volume of the original glass container (EV.sub.G). That number is then multiplied by 100 to obtain the percentage increase in the material volume needed to achieve the weighted feel of the polymeric container. From this percentage, the amount increase in diameter and length of the polymeric container is determined.

(31) For example, the percentage increase in the diameter and length can be between 0.25 and 0.14 of V.sub.P+, more preferably between 0.30 and 0.36 V.sub.P+ and most preferably at 0.333 V.sub.P+. Alternately stated, the ratio of diameters to the polymeric container is larger than the diameter of the glass container to which it is simulating. Correspondingly, the length of the polymeric container is larger than the length of the glass container to which it replaces.

(32) Another feature of the polymeric drinking container is the gradual increased thickness of the enclosed wall 14 from the opening 16 to the base 12. This gradual increase also facilitates the overall weighted feel of the polymeric container in comparison to the glass container which it replaces. This programmed and controlled thickness increase facilitates the clear appearance of the polymeric container once formed and facilitates sufficient rigidity in the polymeric drinking container to withstand its use as a drinking vessel. In a most preferred embodiment, the thickness of the walls of the polymeric container in relation to the glass container follows the same ratios as described above in reference to V.sub.P+.

(33) A polymeric drinking container made as just described will have several advantages which include a gradual uniformly increasing side wall thickness. This allows a functional transparency and clarity when the polymeric material is selected as a clear engineering thermoplastic. Additionally, there will be a lack of obvious or unwanted disruptions of light due to refraction or transmission in the polymeric container so constructed. Additionally, the polymeric container as mentioned has a weight that substantially matches, or simulates, that of the glass containers but has a rigidity and resistance to crunching that matches, or in most cases exceeds, that of glass containers. Typically the rigidity is proportional to the cube of the container sidewall thickness multiplied times the material modulus. In this instance, the polymeric material has increased rigidity and the gradual increase in the sidewall thickness along with the aforementioned dimensional adjustments and volume metric adjustments, has a profound effect on the container resistance to breaking and fragmenting. These engineered thermoplastics in the container have an excellent toughness and are resistant to abuse while having increased their durability. The thermoconductivity of the polymeric container is improved thus providing an approved cooling capacity for the polymeric container in relation to the glass container. This is facilitated by the material used and also in the increased wall thickness of the polymeric material and the polymeric container since the diffusion of heat is proportional to the square of the container wall thickness. In addition, there is a reduced tendency for moisture condensation on the outside of the polymeric container due to this improved cooling capacity. Additionally, there is an improved balance in resisting to tipping or toppling due to the predominance of the polymeric container weight being distributed towards the bottom portion or bottom half of the polymeric container.

(34) In this container, the average container wall thickness of the polymeric container is proportional to the ratio of the specific gravity of the glass, such as 2.52 for soda lime glass, to that of the polymeric material selected, typically between 0.85 to 1.4 for those thermoplastics listed in Tables 1, 2 and 3. Additionally, since the wall thickness in the polymeric container is proportional and gradual along the length of the container, a majority of the weight ends up in the lower half of the polymeric container. This again improves the balance of the container and resistance to tipping and/or toppling.

(35) Thus, although there have been described particular embodiments of the present invention of a new and useful POLYMERIC REPLACEMENT FOR A GLASS DRINKING CONTAINER it is not intended that such references be construed as limitations upon the scope of this invention except as set forth in the following claims.