BLOW MOLDED CONTAINER AND METHOD FOR MAKING SAME - Patent application

Abstract

A container, such as a bottle, is formed by a blow molding process. The container includes a bottom and a sidewall extending from the bottom. The bottom and sidewall define an interior configured to accommodate at least one product. At least one of the sidewall and the bottom has a barrier layer and a desiccant layer attached to the barrier layer. The barrier layer and the desiccant layer are each blow molded together. The barrier layer is located outside the desiccant layer and is made of a plastic material. The desiccant layer is made of a monolithic composition including a mixture of a base polymer, a desiccant, and a channeling agent. [Selected Figure] Figure 1

Description

[Technical field]

[0001] 1.Technical Field The present invention relates to blow molded containers and methods for making same. [Background technology]

[0002] 2.Background technology There are many items that are preferably stored, shipped, and / or utilized in environments that must be controlled and / or regulated. For example, in the moisture control field, it has been recognized that containers and / or packages that have the ability to absorb excess moisture trapped therein are desirable. Control of moisture, oxygen, ethylene, and other gaseous substances may be desirable in medical, diagnostic, industrial chemical, laboratory, electronics, and food packaging applications.

[0003] Traditionally, desiccants, oxygen absorbers, and other active agents have been used in raw form, for example as loose particles contained in a pouch or canister within the packaging, to control the internal environment of the package. In many applications, it is undesirable to have such loosely stored active materials. To address this issue, the assignee of the present application has developed active entrained polymers containing the active agents, which can be extruded and / or molded into desired forms, such as container liners, plugs, film sheets, pellets, and other such structures. Optionally, such active entrained polymers can include a channeling agent, such as polyethylene glycol (PEG), which forms channels between the surface of the entrained polymer and its interior to allow the selected material (e.g., moisture) to permeate the entrained active agent (e.g., a desiccant for absorbing moisture).

[0004] The entrained polymer can be a two-phase blend (i.e., a base polymer and an active agent without a channeling agent) or a three-phase blend (i.e., a base polymer, an active agent, and a channeling agent). Three-phase entrained polymers and methods for making them are described, for example, in U.S. Pat. Nos. 5,911,937, 6,080,350, 6,124,006, 6,130,263, 6,194,079, 6,214,255, 6,486,231, 7,005,459, and U.S. Patent Publication No. 2016 / 0039955, each of which is incorporated herein by reference as if fully set forth. These entrained polymers have traditionally been made as injection molded components, for example as inserts or liners in containers.

[0005] In some applications, it is desirable to store contents in a bottle, a container that features a relatively narrow neck that leads to an opening for dispensing the contents held therein. Bottles, unlike vials or other containers, are typically not made using standard injection molding. Rather, bottles are typically fabricated in a blow molding process. Blow molding involves expanding a hot hollow thermoplastic parison within a mold cavity. The expanded thermoplastic material conforms to the shape of the mold cavity and is allowed to cool / harden to form an article (e.g., a bottle) that corresponds to the shape of the mold cavity. Types of blow molding include, for example, extrusion blow molding, injection blow molding, and injection stretch blow molding.

[0006] Unlike injection molded containers, blow molded bottles cannot be easily fabricated with an insert of entrained desiccant polymer. Rather, the desiccant entrained polymer layer(s) in the blow molded bottle must be a component of the blow molded parison, for example, as a layer in the extrusion composite used to form the parison. By including the desiccant material, which is typically a mineral component (e.g., molecular sieves or silica gel), the flow properties of the entrained polymer are affected, resulting in technical difficulties in the blow molding process. In addition, conventional blow molded containers with desiccant layers do not provide the necessary moisture uptake and capacity required to store contents that require very low (close to zero) relative humidity.

[0007] It would therefore be desirable to provide an improved container, particularly a blow molded bottle, that offers advantages in terms of water absorption and capacity, which would ideally not require a separate desiccant component (e.g., a canister or pouch) by including an integral desiccant layer. Summary of the Invention

[0008] Thus, in one aspect, a container formed by a blow molding process is provided. The container includes a bottom and a sidewall extending from the bottom. The bottom and the sidewall define an interior configured to contain at least one product. At least one of the sidewall and the bottom has a barrier layer and a desiccant layer attached to the barrier layer. The barrier layer and the desiccant layer are each blow molded together, preferably molded as a coextrusion composite. The barrier layer is external to the desiccant layer and is made from a plastic material. The desiccant layer is made from a monolithic composition including a mixture of a base polymer, a desiccant, and a channeling agent.

[0009] Preferably, the container is in the form of a bottle. The bottle defines an interior volume for holding the moisture sensitive product. The bottle comprises a neck and a sidewall, the neck having a first cross-sectional area and the sidewall having a second cross-sectional area, the first cross-sectional area being smaller than the second cross-sectional area. In other words, the neck is narrower in at least one dimension than the remainder of the bottle and is not narrower in any dimension than the remainder of the bottle.

[0010] In any embodiment, the container retains its formed shape under gravity.

[0011] In an optional embodiment, the container defines an interior volume for holding a moisture sensitive product. The container includes a neck and a sidewall, the neck defining a first cross-sectional area and the sidewall defining a second cross-sectional area. The first cross-sectional area is smaller than the second cross-sectional area. The container further includes at least an inner desiccant layer and an outer barrier layer. The inner and outer layers each have a thickness of at least 20 mils and are preferably formed by a blow molding process selected from the group consisting of co-extrusion blow molding, co-injection blow molding, and co-injection stretch blow molding. The inner layer includes a polymeric material and at least 30% by weight, preferably at least 35% by weight, of a desiccant material (optionally a molecular sieve), the outer layer includes a polymeric moisture barrier material, and the container retains its molded shape under gravity. Optionally, the container further includes an intermediate layer including "regrind" of material from the inner and outer walls from other containers that were made and then set aside for recycling.

[0012] Optionally, in any embodiment, the outer layer comprises, consists essentially of, or consists of high density polyethylene (HDPE).

[0013] Optionally, in any embodiment, the outer layer comprises, consists essentially of, or consists of low density polyethylene (LDPE).

[0014] Optionally, in any embodiment, the base polymeric material of the inner layer comprises, consists essentially of, or consists of LDPE.

[0015] In an optional embodiment, a method for making a container is provided. The method includes adding a desiccant (optionally a molecular sieve), a polymer, and a channeling agent together to form a mixture, and forming a container with a neck and a sidewall, the neck defining a first cross-sectional area, the sidewall defining a second cross-sectional area, the first cross-sectional area being smaller than the second cross-sectional area. The container further includes an inner layer and an outer layer, each having a thickness of at least 20 mils, preferably using a blow molding process selected from the group consisting of co-extrusion blow molding, co-injection blow molding, and co-injection stretch blow molding. The inner layer includes at least 30% by weight, preferably at least 35% by weight, of a mixture of desiccant and polymeric material, the outer layer includes a barrier material made from a polymer, and the container retains its molded shape under gravity. [Brief description of the drawings]

[0016] The present invention is described in conjunction with the following drawings, in which like reference numbers indicate like elements and in which:

[0017] [Figure 1] FIG. 13 is a schematic perspective view of a plug formed from an entrained polymer, according to an optional embodiment of the present invention.

[0018] [Diagram 2] 2 is a cross-section taken along line 2-2 of FIG. 1.

[0019] [Diagram 3] 3 is a cross-section similar to that of FIG. 2 showing a plug formed from another embodiment of an entrained polymer, according to an optional embodiment of the invention.

[0020] [Figure 4] 1 is a schematic diagram of an entrained polymer, according to an optional embodiment of the present invention, where the active agent is an absorbent material, e.g., a desiccant.

[0021] [Diagram 5] FIG. 1 is a simplified cross-sectional view of a container (bottle) formed by a blow molding process in accordance with one non-limiting embodiment of the disclosed concepts.

[0022] [Figure 6A-6C] 6A-6C are different enlarged cross-sectional views of the side wall of the container of FIG. 5, each corresponding to an alternative embodiment in which the container may be implemented.

[0023] [Figure 7] 6B is a graph illustrating relative humidity control of the desiccant layer of FIG. 6A over time in a container in accordance with the disclosed concepts.

[0024] [Figure 8] 1 is a graph showing relative humidity control by various desiccants over time for a prior art container. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] definition As used herein, the term "active" is defined as being capable of acting, interacting, or reacting with a selected material (e.g., moisture or oxygen) in accordance with the present invention. Examples of such acting or interacting may include absorbing, adsorbing, or releasing the selected material.

[0026] As used herein, the term "active agent" is defined as a material that (1) is immiscible with the base polymer and does not dissolve when mixed with the base polymer and channeling agent and heated, i.e., has a melting point higher than the melting point of either the base polymer or the channeling agent, and (2) acts on, interacts with, or reacts with a selected material. The term "active agent" may include, but is not limited to, materials that absorb, adsorb, or release the selected material(s). Active agents according to the present invention may be in the form of particles, preferably minerals, although the present invention should not generally be considered limited to only particulate active agents (unless otherwise stated in the respective claims).

[0027] As used herein, the term "base polymer" refers to a polymer having a gas permeability of the selected material that is substantially lower, lower, or substantially equal to that of the channeling agent, optionally. By way of example, such a permeability is the water vapor permeability in an embodiment in which the selected material is moisture and the active agent is a water-absorbing desiccant. The main function of the base polymer is to provide a structure for the entrained polymer. Suitable base polymers include thermoplastic polymers, such as polyolefins, such as polypropylene and polyethylene, polyisoprene, polybutadiene, polybutene, polysiloxane, polycarbonate, polyamide, ethylene-vinyl acetate copolymer, ethylene-methacrylate copolymer, poly(vinyl chloride), polystyrene, polyester, polyanhydride, polyacrylonitrile, polysulfone, polyacrylic ester, acrylic acid, polyurethane, and polyacetal, or copolymers or mixtures thereof.

[0028] With reference to such a comparison of the moisture vapor transmission rates of the base polymer and the channeling agent, in one embodiment, the channeling agent has a moisture vapor transmission rate that is at least twice that of the base polymer. In another embodiment, the channeling agent has a moisture vapor transmission rate that is at least 5 times that of the base polymer. In another embodiment, the channeling agent has a moisture vapor transmission rate that is at least 10 times that of the base polymer. In yet another embodiment, the channeling agent has a moisture vapor transmission rate that is at least 20 times that of the base polymer. In yet another embodiment, the channeling agent has a moisture vapor transmission rate that is at least 50 times that of the base polymer. In yet another embodiment, the channeling agent has a moisture vapor transmission rate that is at least 100 times that of the base polymer.

[0029] As used herein, the term "channeling agent" or "channeling agents" is defined as a material that is immiscible with a base polymer and has an affinity to transport a gas phase substance at a faster rate than the base polymer. Optionally, the channeling agent can form channels through the entrained polymer when the entrained polymer is formed by mixing the channeling agent with the base polymer. Optionally, such channels can permeate a selected material through the entrained polymer at a faster rate than the base polymer alone.

[0030] As used herein, the term "channel" or "interconnected channels" is defined as passages formed from a channeling agent that can penetrate the base polymer and interconnect with one another.

[0031] As used herein, the term "entrained polymer" is defined as a monolithic material formed from at least a base polymer having an active agent and, optionally, a channeling agent entrained or distributed throughout. Entrained polymers thus include two-phase and three-phase polymers. A "mineral-filled polymer" is a type of entrained polymer in which the active agent is in the form of a mineral, e.g., mineral particles such as molecular sieves or silica gel.

[0032] As used herein, the terms "monolithic," "monolithic structure," or "monolithic composition" are defined as a composition or material that is not composed of two or more separate macroscopic layers or portions. Thus, a "monolithic composition" does not include a multilayer composite (although it may be part of a multilayer composite).

[0033] As used herein, the term "phase" is defined as a portion or component of a monolithic structure or composition that is uniformly distributed throughout and gives the structure or composition its monolithic characteristics.

[0034] As used herein, the term "selected material" is defined as a material that can act on or interact or react with the active agent and permeate through the channels of the entrained polymer. For example, in embodiments where a desiccant is used as the active agent, the selected material can be moisture or gas that can be absorbed by the desiccant. In embodiments where an emissive material is used as the active agent, the selected material can be an agent released by the emissive material, such as moisture, fragrance, or antimicrobial agents. In embodiments where an adsorbent material is used as the active agent, the selected material can be a specific volatile organic compound and the adsorbent material can be activated carbon.

[0035] As used herein, the term "three-phase" is defined as a monolithic composition or structure that includes three or more phases. An example of a three-phase composition according to the present invention may be an entrained polymer formed from a base polymer, an active agent, and a channeling agent. Optionally, the three-phase composition or structure may include an additional phase, such as a colorant (thus, "three-phase" refers to at least three phases including a base polymer, an active agent, and a channeling agent).

[0036] Exemplary Entrained Polymers 1-4 show exemplary entrained polymers 10 and various package assemblies formed from the entrained polymers in accordance with the present invention. The entrained polymers 10 each include a base polymer 25, a channeling agent 35, and an active agent 30. As shown, the channeling agent 35 forms interconnecting channels 45 through the entrained polymer 10. At least some of the active agent 30 is contained within these channels 45 such that the channels 45 communicate between the active agent 30 and the exterior of the entrained polymer 10 through channel openings 48 formed in the exterior surface of the entrained polymer 25. The active agent 30 can be, for example, any one of a variety of absorbing, adsorbing, or releasing materials, as described in more detail below.

[0037] Suitable channeling agents may include polyglycols such as polyethylene glycol (PEG), ethylene-vinyl alcohol (EVOH), polyvinyl alcohol (PVOH), glycerin polyamines, polyurethanes, and polycarboxylic acids including polyacrylic acid or polymethacrylic acid. Alternatively, the channeling agent 35 may be a water soluble polymer such as, for example, a propylene oxide polymer-monobutyl ether such as Polyglykol B01 / 240 produced by CLARIANT. In other embodiments, the channeling agent may be a propylene oxide polymer-monobutyl ether such as Polyglykol B01 / 20 produced by CLARIANT, a propylene oxide polymer such as Polyglykol D01 / 240 produced by CLARIANT, ethylene vinyl acetate (EVA), nylon 6, nylon 66, or any combination of the foregoing.

[0038] Suitable active agents according to the present invention include absorbing materials such as drying compounds. Figure 4 shows an embodiment of an entrained polymer 10 according to the present invention where the active agent 30 is an absorbing or adsorbing material. The arrows indicate the path of a selected material, e.g., moisture or gas, from the outside of the entrained polymer 10, through channels 45, to the particles of the active agent 30 that absorb or adsorb the selected material.

[0039] When the active agent is a desiccant, any desiccant suitable for a given application may be used. Typically, physical absorption desiccants are preferred for many applications. These may include molecular sieves, silica gel, clay, and starch. Alternatively, the desiccant may be a chemical compound that forms crystals containing water, or a compound that reacts with water to form a new compound.

[0040] Optionally, in any embodiment, the active agent can be an oxygen scavenger.

[0041] Suitable absorbing materials include, in optional embodiments, (1) metals and alloys, such as, but not limited to, nickel, copper, aluminum, silicon, solder, silver, and gold; (2) metal plated particles, such as silver plated copper, silver plated nickel, and silver plated glass microspheres; and (3) BaTiO 3 , SrTiO 3 , SiO 2 , Al 2 O 3 , ZnO, TiO 2 , MnO, CuO, Sb 2 O 3 (3) inorganic materials such as WC, fused silica, fumed silica, amorphous fused silica, sol-gel silica, sol-gel titanates, mixed titanates, ion exchange resins, lithium-containing ceramics, hollow glass microspheres, (4) carbon-based materials such as carbon, activated carbon, carbon black, Ketjen black, diamond powder, (5) elastomers such as polybutadiene, polysiloxanes, and semi-metals, ceramics, and (6) other fillers and pigments.

[0042] In another example, the absorbent material can be a carbon dioxide scavenger, such as calcium oxide. In the presence of moisture and carbon dioxide, calcium oxide is converted to calcium carbonate. Thus, calcium oxide can be used as an absorbent material in applications where absorption of carbon dioxide is required. Such applications include preservation of fresh foods (e.g., fruits and vegetables) that give off carbon dioxide.

[0043] Other suitable active agents according to the present invention include releasing materials. Such materials may include any suitable material that releases selected materials from the releasing materials. The selected materials released from the releasing materials may be in the form of solids, gels, liquids, or gases. These materials may perform a variety of functions, including acting as a source of fragrance, flavor, or perfume, providing biologically active ingredients such as insecticides, pest repellents, antibacterial agents, bait, fragrances, etc., providing humidifying or drying materials, delivering air-active chemicals such as corrosion inhibitors, ripening agents, and odor generating agents.

[0044] Biocides suitable for use as a release material in the entrained polymers of the present invention may include, but are not limited to, insecticides, herbicides, nematicides, fungicides, rodenticides, and / or mixtures thereof. In addition to biocides, the coatings of the present invention may also release nutrients, plant growth regulators, pheromones, defoliants, and / or mixtures thereof.

[0045] Quaternary ammonium compounds can also be used as a release material according to the present invention. Such compounds not only function as surfactants, but also impart sterility to the surface of the entrained polymer or establish conditions for reducing the number of microorganisms, some of which may be pathogenic. Many other antibacterial agents, such as benzalkonium chloride and related classes of compounds such as hexachlorophene, may also be used as a release agent according to the present invention. Other antibacterial agents, such as chlorine dioxide release agents, may also be used.

[0046] Other potential release materials include fragrances, including natural, essential oils, and synthetic flavors, and blends thereof. Typical flavor materials that may form part or in some cases the entirety of the active ingredient include natural essential oils, such as lemon oil, mandarin oil, clove leaf oil, petitgrain oil, cedarwood oil, patchouli oil, lavandin oil, neroli oil, ylang oil, pure rose oil, or pure jasmine oil; natural resins, such as labdanum resin or olibanum resin; and alcohols, such as geraniol, nerol, citronellol, linalool, tetrahydrogeraniol, beta phenylethyl alcohol, methylphenylcarbinol, dimethylbenzylcarbinol, menthol, or cedrol, which may be isolated from natural sources or may be used as such. or single fragrance chemicals which may be synthetically produced; acetates and other esters derived from such alcohol-aldehydes, such as citral, citronellal, hydroxycitronellal, lauric aldehyde, undecylenic aldehyde, cinnamaldehyde, amyl cinnamaldehyde, vanillin, or heliotropin; acetals derived from such aldehydes; ketones, such as methylhexyl ketone, ionones, and methyl ionone; phenolic compounds, such as eugenol and isoeugenol; and synthetic musks, such as musk xylene, musk ketone, and ethylene brassylate.

[0047] It is believed that the higher the active agent concentration in the mixture, the greater the absorption, adsorption, or release capacity (as the case may be) of the final composition. However, if the active agent concentration is too high, the entrained polymer may become more brittle and the molten mixture of active agent, base polymer, and channeling agent may become more difficult to either thermoform, extrude, or injection mold. In one embodiment, the active agent loading level may range from 10% to 80%, preferably 35% to 70%, more preferably 40% to 60%, and even more preferably 45% to 55%, based on the total weight of the entrained polymer. Optionally, the channeling agent may be provided in the range of 2% to 15% by weight, optionally 2 to 12% by weight, optionally 5 to 12% by weight, optionally about 10% by weight, optionally about 9% by weight, optionally about 8% by weight, optionally about 7% by weight, optionally about 6% by weight, optionally about 5% by weight, optionally about 4% by weight, optionally about 3% by weight, optionally about 2% by weight. Optionally, the base polymer may be in the range of 10% to 60% by weight, optionally 20% to 45% by weight, optionally 25% to 35% by weight of the total composition. Optionally, the colorant is added, for example, at about 0.5 to 2% by weight or about 1% by weight of the total composition. Any combination of the above ranges for the base polymer, active agent, channeling agent, and colorant is contemplated.

[0048] Referring to Figure 1, there is shown an insert 20 constructed from an entrained polymer usable in the present invention. The insert 20 is in the form of a plug 55 that can be deposited within a container, as shown. This plug form is not the form contemplated for use in blow molded bottles, but is provided in this drawing to generally illustrate the composition of a three-phase entrained polymeric material that can be used in the inner layer of a bottle.

[0049] 2, there is shown a cross-sectional view of a plug 55 constructed from an entrained polymer 10 comprising a base polymer 25 homogeneously blended with an active agent 30 and a hydrophilic or channeling agent 35. In the view of FIG. 2, the entrained polymer has been solidified such that interconnected channels 45 have been formed throughout the entrained polymer 10, establishing passageways throughout the solidified plug 55. As can be seen from both FIGS. 1 and 2, the passageways terminate at channel openings 48 on the exterior surface of the plug 55.

[0050] FIG. 3 shows an embodiment of a plug 55 of similar structure and configuration to that of FIG. 2, with the interconnecting channels 45 being much finer as compared to those of FIG. 2. This may be due to the use of a dimerizing agent (i.e., a plasticizer) along with the channeling agent 35. The dimerizing agent may enhance the compatibility between the base polymer 25 and the channeling agent 35. This enhanced compatibility is facilitated by the reduced viscosity of the blend, which may promote a more thorough blending of the base polymer 25 and the channeling agent 35, which may resist combining into a homogenous solution under normal conditions. Upon solidifying the entrained polymer 10 with the dimerizing agent added thereto, the interconnecting channels 45 formed through the entrained polymer 10 become more dispersed and less porous, thereby establishing a greater density of interconnecting channels throughout the plug 55.

[0051] Interconnecting channels 45, such as those disclosed herein, facilitate the permeation of desired materials, such as moisture, gases, or odors, through the base polymer 25, which generally resists penetration of these materials and acts as a barrier to the materials. Thus, the base polymer 25 itself acts as a barrier material in which the active agent 30 can be entrained. The interconnecting channels 45 formed from the channeling agent 35 provide a path for the desired materials to travel through the entraining polymer 10. Without these interconnecting channels 45, it is believed that a relatively small amount of the desired materials would be delivered to or from the active agent 30 through the base polymer 25. If the desired materials are delivered to the active agent 30, for example in embodiments where the active agent 30 is an active agent such as a desiccant or oxygen absorber, the desired materials can be absorbed by the active agent 30. If the desired materials are delivered from the active agent 30, for example in embodiments where the active agent 30 is an emitting material such as a fragrance or gas emitting material, the desired materials can be released from the active agent 30.

[0052] 5 is a simplified cross-sectional view of a container 100, e.g., a bottle, formed by a blow molding process in accordance with one non-limiting embodiment of the disclosed concepts. The illustrated container 100 includes a bottom 102 and a sidewall 104 extending from the bottom 102. The bottom 102 and the sidewall 104 define an interior 106 configured to contain at least one product (e.g., but not limited to, pills, powders, etc.). The container 100 may also optionally include a lid 110 configured to be coupled to an open top 112 or neck of the sidewall 104 to enclose the product within the interior 106. In accordance with the disclosed concepts, as discussed below, the container 100 is formed by a blow molding process, with the bottom 102 and / or the sidewall 104 being composed of layers different from those of existing prior art blow molded containers that do not utilize channeling agents. As a result, container 100 offers significant advantages in terms of moisture control, exposure to water-absorbing materials, and / or efficiency with respect to the manufacturing process, as compared to prior art blow molded containers.

[0053] FIG. 6A shows a close-up view corresponding to a first optional embodiment in which the container of FIG. 5 may be implemented. As shown, the sidewall 104 generally has a barrier layer 120 and a desiccant layer 122 attached to the barrier layer 120. The barrier layer 120 and the desiccant layer 122 are each blow-molded together, with the barrier layer 120 located on the outside relative to the desiccant layer 122. The barrier layer 120 is made of any suitable plastic material. In accordance with the disclosed concepts, the desiccant layer 122 may be made of a monolithic composition including a mixture of a base polymer, a desiccant, and a channeling agent. As will become more apparent below with reference to FIGS. 7 and 8, the desiccant layer 122, which differs from the water-absorbing materials and / or layers of prior art containers that do not utilize a channeling agent, provides significant unexpected results in terms of water absorption within the interior 106.

[0054] In one optional embodiment, the desiccant layer 122 has a thickness of 25-35 mils, preferably about 0.8 millimeters. In one optional embodiment, the desiccant layer 122 includes 30%-80% molecular sieves. In one optional embodiment, the channeling agent of the desiccant layer 122 is 5%-10% by weight of the monolithic composition. In one optional embodiment, the desiccant layer 122 has a porous structure. In one optional embodiment, the barrier layer 120 has a non-porous structure. In one optional embodiment, the desiccant of the desiccant layer 122 is calcium oxide. In one optional embodiment, the ratio of desiccant to base polymer is about 75 parts desiccant to 20 parts base polymer by weight. 6A has been described in connection with the sidewall 104 (including the neck 112), it will be appreciated that the bottom 102 may also have barrier and desiccant layers substantially identical to the barrier and desiccant layers 120, 122, respectively, in accordance with the disclosed concepts. That is, the barrier and desiccant layers of the bottom 102 may be continuous with the barrier and desiccant layers 120, 122 of the sidewall 104.

[0055] 6B shows a close-up view corresponding to a second optional embodiment in which the container of FIG. 5 may be implemented. As shown, in addition to the barrier layer 120' and the desiccant layer 122', the sidewall 104' further includes a relatively thin skin layer 124' attached to the desiccant layer 122'. The barrier layer 120', the desiccant layer 122', and the skin layer 124' are each preferably blown together (e.g., from a co-extruded composite material), and as shown, the desiccant layer 122' and the barrier layer 120' are each respectively located outwardly relative to the skin layer 124'. In one exemplary embodiment, the skin layer 124' is made from a plastic material, optionally a low-density polyethylene material. It will be appreciated that the skin layer 124' advantageously functions to minimize the possibility of desiccant particles from the desiccant layer 122' entering the interior 106 (FIG. 5) of the container 100 (FIG. 5). Moreover, the skin layer 124' can accomplish this function without significantly impairing the water absorption ability of the desiccant layer 122'. That is, even though the skin layer 124' is between the desiccant layer 122' and the interior 106 (FIG. 5) of the container 100 (FIG. 5), the desiccant layer 122' can still fully absorb moisture. In one optional embodiment, the skin layer 124' has a thickness of 0.005 mm to 0.1 mm, optionally 0.005 mm to 0.05 mm, optionally about 0.01 mm.

[0056] FIG. 6C shows an enlarged view corresponding to a third optional embodiment in which the container of FIG. 5 may be implemented, with like reference numbers indicating like components. As shown, in addition to the barrier layer 120″, the desiccant layer 122″, and the skin layer 124″, the sidewall 104″ further has an intermediate layer 126″ located between the barrier layer 120″ and the desiccant layer 122″. In one optional embodiment, the intermediate layer 126″ is made of a monolithic composition including a plastic material and a mixture of a base polymer, a desiccant, and a channeling agent. In other words, the intermediate layer 126″ may be a monolithic composition including, for example, a recycled portion of the sidewall 104 of the first embodiment shown in FIG. 6A. It will thus be understood that the regrind sidewall 104 material can be reused in another container, for example, the container containing the sidewall 104″. This provides an advantage in terms of reducing waste. That is, compared to prior art containers and methods of making prior art containers that result in occasional disposal of containers (e.g., but not limited to, containers that may have been distorted during manufacturing), container 100 including sidewall 104'' advantageously recycles such materials while still providing a significant improvement in terms of water absorption.

[0057] It will be appreciated that a method of manufacturing container 100 (FIG. 5) includes the steps of providing a stock component, inserting a device into an opening in the stock component, and passing air through the opening in the stock component to form container 100.

[0058] Optionally, in any embodiment, the container 100 may have a total wall thickness of 10-80 mils, optionally 20-60 mils, optionally 20-40 mils. The container 100 may be even thicker than 80 mils in some applications. In one optional embodiment, the container 100 includes a 20-40 mil thick wall and / or a 20-40 mil thick desiccant layer. In another optional embodiment, the container 100 includes a 20 mil barrier layer and a 20 mil desiccant entrained polymer layer. The barrier layer material is not particularly limited. For example, HDPE, LDPE, PE, or any non-moisture permeable material may be used.

[0059] 7 shows a graph illustrating the relative humidity control of the desiccant layer 122 of FIG. 6A versus time in the container 100 (shown as percent relative humidity on the Y-axis of the graph), in accordance with an optional aspect of the disclosed concepts. The desiccant used in this embodiment was a molecular sieve, and a channeling agent was also used in the desiccant layer (i.e., it was a three-phase composition). As shown, about 0.2 days after initial closure, the relative humidity in the container 100 dropped from over 60% to about 0 and remained there--an impressive result. Additional information regarding this data is provided in Example 1 below.

[0060] Figure 8 shows a graph illustrating the relative humidity control of the desiccant layer over time for a prior art blow molded container having a desiccant entrained polymer layer (as described in U.S. Pat. No. 8,110,260). The desiccant layer of the prior art container contained molecular sieves and lacked a channeling agent, instead using a blowing agent. As shown in Figure 8, about 0.2 days after initial closure, the relative humidity in the prior art container (with the molecular sieve desiccant layer) was about 13% to about 15%.

[0061] It can thus be seen that the novel blow molded container 100 in accordance with the disclosed concepts has achieved significant and unexpected results. Specifically, by blow molding the container 100 with a desiccant layer 122 comprising a base polymer, a desiccant, and a channeling agent, as opposed to prior art methods lacking a channeling agent, a significant water absorption advantage is provided, as can be seen with reference to Figures 7 and 8.

[0062] Achieving adequate melt flow during extrusion and blow molding can be difficult because particulate desiccants (e.g., molecular sieves) can significantly retard flow. Optionally, in the process of making any of the embodiments disclosed herein, the process conditions should result in a melt flow index (ISO1133-1) of 0.5 to 2, optionally 1 to 2.

[0063] 6A-6C, it will be understood that suitable alternatives are contemplated herein, i.e., the sidewalls and / or bottom of a container in accordance with the disclosed concepts may have one or more barrier layers, desiccant layers, skin layers, intermediate layers, and / or alternative layers without departing from the scope of the disclosed concepts.

[0064] In yet another alternative embodiment of the disclosed concept, a blow molded bottle is provided that comprises or consists essentially of a single layer of desiccant-entrained polymer or regrind (e.g., 50% desiccant-entrained polymer and 50% virgin polypropylene or HDPE). Such an embodiment would require storage (at least prior to consumer use) in a secondary packaging that provides a barrier to moisture, e.g., a foil pouch. The desiccant-entrained polymer in this embodiment would comprise a base polymer, a desiccant, and a channeling agent (i.e., comprising a three-phase composition).

[0065] Various aspects of the present invention will be illustrated in more detail with reference to the following examples, but it should be understood that the invention is not to be considered as limited thereto. EXAMPLES

[0066] A blow molded bottle 100 (150 mL) according to FIGS. 5 and 6A was prepared using the formulation in Table 1 below as the desiccant layer 122 (20-40 mil) and HDPE (20-40 mil) as the barrier layer 120. [Table 1]

[0067] The change in relative humidity inside the bottle was measured. The data for Sample 2 is graphed in Figure 7. Sample 2 was exposed to 80% relative humidity at 30°C and allowed to reach equilibrium. The bottle was then sealed and the internal humidity level was monitored for approximately 26 hours.

[0068] Although the disclosed concepts have been described in detail with reference to specific embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. DISCLOSURE OF THEINVENTION (Section 1) A container, optionally a bottle, formed by a blow moulding process, said container comprising: The bottom and a sidewall extending from the base, the base and the sidewall defining an interior configured to contain at least one product; Equipped with A container, wherein at least one of the sidewalls and the bottom has a barrier layer and a desiccant layer attached to the barrier layer, the barrier layer and the desiccant layer are each blow molded together, the barrier layer is disposed outwardly relative to the desiccant layer and is made from a plastic material, the desiccant layer is made from a monolithic composition comprising a mixture of a base polymer, a desiccant, and a channeling agent, and the container retains its molded shape under gravity. (Section 2) Item 1. The container of item 1, wherein the barrier layer and the desiccant layer each have a thickness of at least 20 mils, optionally from 20 to 40 mils, optionally from 25 to 35 mils. (Section 3) 3. The container of claim 1 or 2, wherein the desiccant layer comprises 30% to 80% molecular sieve, optionally 30% to 60% molecular sieve, optionally 35% to 55% molecular sieve. (Section 4) 4. The container according to any one of items 1 to 3, wherein the channeling agent is 2% to 15% by weight, optionally 5% to 10% by weight, of the monolithic composition. (Section 5) 5. The container according to any one of items 1 to 4, wherein the desiccant layer includes interconnected channels formed by the channeling agent. (Section 6) Item 6. The container according to any one of items 1 to 5, wherein the barrier layer has a non-porous structure. (Section 7) 7. The container according to any one of items 1 to 6, wherein the desiccant is a molecular sieve. (Section 8) Item 8. The container according to any one of items 1 to 7, wherein the ratio of the desiccant to the base polymer in the desiccant layer is about 2 parts by weight of the desiccant to 1 part by weight of the base polymer. (Section 9) Item 9. The container according to any one of items 1 to 8, wherein the at least one of the sidewall and the bottom further has a skin layer attached to the desiccant layer, the barrier layer, the desiccant layer, and the skin layer are each blown together, and the barrier layer and the desiccant layer are each disposed outwardly relative to the skin layer. (Section 10) Item 10. The container according to item 9, wherein the skin layer is made of a plastic material. (Section 11) Item 11. The container of item 10, wherein the skin layer is made from low density polyethylene. (Section 12) Item 12. The container according to any one of items 1 to 11, wherein the at least one of the sidewall and the bottom further comprises an intermediate layer disposed between the barrier layer and the desiccant layer. (Section 13) Item 13. The container of item 12, wherein the intermediate layer is made from a monolithic composition comprising a plastic material and a mixture of a base polymer, a desiccant, and a channeling agent. (Section 14) Item 14. The container according to any one of items 1 to 13, wherein the channeling agent is EVA. (Section 15) 1. A method of manufacturing a container, the container comprising a bottom and a sidewall extending from the bottom, the bottom and the sidewall defining an interior configured to contain at least one product, the method comprising: Providing stock components; inserting a device into an opening in the stock component; passing air through the opening of the stock component to form the container, wherein at least one of the sidewall and the bottom has a barrier layer and a desiccant layer attached to the barrier layer, the barrier layer and the desiccant layer are each blown together, the barrier layer being outwardly disposed relative to the desiccant layer and being made from a plastic material, the desiccant layer being made from a monolithic composition including a mixture of a base polymer, a desiccant, and a channeling agent; The method includes:

Claims

[Claim 1] 1. A method of manufacturing a bottle, the bottle comprising: a bottom; and a sidewall extending from the bottom, the bottom and the sidewall defining an interior configured to contain at least one product, the sidewall extending to a neck leading to a dispensing opening, the neck defining a first cross-sectional area, the sidewall defining a second cross-sectional area, the first cross-sectional area being smaller than the second cross-sectional area, the method comprising: Providing stock components; inserting a device into an opening in the stock component; passing air through the opening in the stock component to form the bottle; At least one of the sidewall and the bottom has a barrier layer and a desiccant layer attached to the barrier layer, the barrier layer and the desiccant layer are each blow molded together, the barrier layer is disposed outwardly relative to the desiccant layer and is made of a plastic material; The method is characterized in that the desiccant layer is made from a monolithic composition comprising a mixture of a polyolefin base polymer, a molecular sieve as a desiccant, and ethylene vinyl acetate (EVA) as a channeling agent, the molecular sieve comprising 30% to 80% of the monolithic composition, and the EVA comprising 2% to 15% by weight of the monolithic composition.

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