Barrier forming system and method for dry molded structures

Abstract

A barrier forming system for a dry formed cellulose fiber container includes a support structure configured to support a dry formed cellulose fiber structure, a barrier material disposed proximate the support structure, and a force generating mechanism configured to move at least one of the barrier material and the dry formed cellulose fiber structure into contact with each other.

Description

BARRIER FORMING SYSTEM AND METHOD FOR DRY MOLDED STRUCTURESCROSS REFERENCE TO RELATED APPLICATIONSThis application claims the benefit of U.S. Application No. 63 / 637,503, filed on April 23, 2024, which is incorporated herein by reference in its entirety.BACKGROUND

[0001] The present disclosure relates to dry molded cellulose fiber structures and, more specifically, to a barrier forming system and method for dry molded structures.

[0002] Molded fiber production, which involves producing products, e.g., cardboard, cups, plates, bowls, bottles, and egg packaging, using cellulose fibers, has been around for a long time. Conventionally, a process called wet forming, which involves dispersing cellulose fibers in an aqueous medium to form a pulp slurry, molding the pulp slurry, and drying the molded pulp slurry to form the product. Various chemical and / or mechanical processes may be involved to improve the wet forming process.

[0003] Recent advances have been made in molded fiber production with respect to dry molded fiber. Dry molded fiber is produced via a dry molding process that does not require dispersing the cellulose fibers in an aqueous medium. Instead, dry molding involves an air-formed cellulose blank disposed within a forming mold and subjecting the cellulose blank to a high temperatures and pressures which forms the dry molded product. The dry mold may use fluff pulp formed from, e.g., softwood fiber. For example, the dry molded product may be formed at 600PSI and 140-200°C. During the dry forming process, Hydrogen bonding and fibril aggregation may form the dry formed cellulose fiber structure.

[0004] Molded fiber production, including dry molding, converts renewable plant fibers into sustainable packaging and products. Molded fiber production is a sustainable alternative to single use plastics that is acceptable with respect to speed, scalability, and cost. The dry molding process has advantages including reduction in time and cost, with the drying step being removed, and the dry molded product may have superior strength and other mechanical properties compared to wet molded products.SUMMARY

[0005] In accordance with a non-limiting example, A barrier forming system for a dry formed cellulose fiber container comprises a support structure configured to support a dry formed cellulose fiber structure, a barrier material disposed proximate the support structure,and a force generating mechanism configured to move at least one of the barrier material and the dry formed cellulose fiber structure into contact with each other.

[0006] In addition to one or more of the features described herein, the barrier material forming system further comprises a vacuum system configured to vacuum out gas between the barrier material and the dry formed cellulose fiber structure such that the barrier material conforms to the dry formed cellulose fiber structure.

[0007] In addition to one or more of the features described herein, the support structure is a vacuum casing.

[0008] In addition to one or more of the features described herein, the vacuum casing is operable to be connected to a pump or a blower of the vacuum system that vacuums out gas within the vacuum casing to force the gas between the barrier material and the dry formed cellulose fiber structure through the dry formed cellulose fiber structure.

[0009] In addition to one or more of the features described herein, the barrier forming system further comprises a heater assembly configured to heat the barrier material prior to vacuuming out the gas between the barrier material and the dry formed cellulose fiber structure.

[0010] In addition to one or more of the features described herein, the heater assembly comprises a heating element configured to radiate infrared wavelengths to heat the barrier material.

[0011] In addition to one or more of the features described herein, the force generating mechanism assembly comprises a plunger assembly configured to push a portion of the barrier material towards the dry formed cellulose fiber structure or the dry formed cellulose fiber structure towards the barrier material.

[0012] In addition to one or more of the features described herein, the plunger assembly comprises a plunger operably connected to an actuator that is configured to actuate the plunger towards the barrier material.

[0013] In addition to one or more of the features described herein, the plunger assembly comprises a plunger having an insulated surface configured to contact the barrier material.

[0014] In addition to one or more of the features described herein, the plunger assembly comprises a plunger having one or more air injection holes formed therein.

[0015] In addition to one or more of the features described herein, the plunger assembly is operably connected to a pump or a blower configured to inject air through the one or more air injection holes towards the barrier material.

[0016] In addition to one or more of the features described herein, the barrier material is a thermoplastic sheet or film.

[0017] In accordance with a non-limiting example, a method for forming a dry formed cellulose fiber container comprises placing a barrier material proximate a dry formed cellulose fiber structure, and allowing the barrier material to conform to the dry formed cellulose fiber structure..

[0018] In addition to one or more of the features described herein, the method further comprises heating the barrier material via a heater assembly.

[0019] In addition to one or more of the features described herein, the method further comprises moving the barrier material towards the cellulose fiber structure or moving the cellulose fiber structure towards the barrier material via a plunger assembly.

[0020] In addition to one or more of the features described herein, the method further comprises vacuuming out gas between the barrier material and the dry formed cellulose fiber structure through the dry formed cellulose fiber structure.

[0021] In addition to one or more of the features described herein, the barrier material is heated to a predetermined temperature and held at the predetermined temperature for a predetermined period to reduce residual orientation stresses.

[0022] In addition to one or more of the features described herein, the heater assembly heats the barrier material via infrared wavelength radiation.

[0023] In addition to one or more of the features described herein, air is injected towards the barrier material via one or more air injection holes formed in a plunger of the plunger assembly.

[0024] In addition to one or more of the features described herein, the barrier material is a thermoplastic sheet or film.

[0025] In addition to one or more of the features described herein, the method further comprises heating the barrier material via a heater assembly, moving the barrier material heated by the heater assembly towards the cellulose fiber structure or moving the cellulose fiber structure towards the barrier material heated by the heater assembly, vacuuming out gas between the barrier material and the dry formed cellulose fiber structure through the dry formed cellulose fiber structure, and cooling the barrier material such that the barrier material conforms to the cellulose fiber structure

[0026] In accordance with a non-limiting example, a dry formed cellulose fiber container is formed by a method comprising placing a barrier material proximate a dryformed cellulose fiber structure, and allowing the barrier material to conform to the dry formed cellulose fiber structure.

[0027] In addition to one or more of the features described herein, the barrier forming system is configured to adhere the barrier material to the dry formed cellulose fiber structure.

[0028] In addition to one or more of the features described herein, the barrier forming system is configured to dispose adhesive onto the dry formed cellulose fiber structure to adhere the barrier material to the dry formed cellulose fiber structure.

[0029] In addition to one or more of the features described herein, the barrier forming system further comprises a clamping structure configured to clamp a perimeter of the barrier material to be stationary.

[0030] In addition to one or more of the features described herein, the clamping structure forms a seal at the perimeter of the barrier material.

[0031] In addition to one or more of the features described herein, apertures are formed in the dry formed cellulose fiber structure to transmit vacuum through the dry formed cellulose fiber structure.

[0032] In addition to one or more of the features described herein, the force generating mechanism comprises a pressure generating mechanism that generates a positive pressure on the barrier material to push the barrier material towards the dry formed cellulose fiber structure.

[0033] In addition to one or more of the features described herein, the barrier forming system further comprises a cooling assembly configured to cool the barrier material.

[0034] The above features and advantages, and other features and advantages of the disclosure are readily apparent from the following detailed description when taken in connection with the accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Fig. 1 shows a schematic diagram of a barrier forming system according to one or more embodiments;

[0036] Fig. 2 shows a barrier forming assembly according to one or more embodiments;

[0037] Fig. 3 shows a barrier forming assembly according to one or more embodiments;

[0038] Fig. 4 shows a barrier forming assembly according to one or more embodiments;

[0039] Fig. 5 shows a barrier forming assembly according to one or more embodiments;

[0040] Fig. 6 shows a barrier forming assembly according to one or more embodiments;

[0041] Fig. 7 shows a barrier forming assembly according to one or more embodiments;

[0042] Fig. 8 shows a barrier forming assembly according to one or more embodiments;

[0043] Figs. 9A-9C show steps of a barrier forming process according to one or more embodiments;

[0044] Figs. 10A-10F show steps of a barrier forming process according to one or more embodiments;

[0045] Fig. 11 shows a barrier forming assembly according to one or more embodiments; and

[0046] Fig. 12 shows a barrier forming assembly according to one or more embodiments.DETAILED DESCRIPTION

[0047] The following description is merely exemplary in nature and is not intended to limit the present disclosure, its application or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.

[0048] A wet forming process may allow for chemicals to be added to the pulp slurry to add desired characteristics of the wet formed molded cellulose fiber products. For example, additives may be included in the pulp slurry, and when the pulp slurry is dried, these additives may impart water-resistant or water-proof characteristics to the wet formed molded cellulose fiber products. Examples of additives include wax, polyamide epichlorohydrin, and cationic starch. Thus, the wet formed molded cellulose fiber products may be used in applications in which they hold (or at least may come in contact with) liquids.

[0049] Though elimination of wet forming steps, such as dispersing the cellulose fiber in an aqueous medium and drying the pulp slurry, has advantages including reduction of time, energy, and cost, elimination of such steps also removes the opportunity to add one or more additives that may impart water-resistant or water-proof characteristics to the molded cellulose fiber products. Without such additives, dry molded cellulose fiber structures areporous and lacking in barrier properties. For example, dry molded cellulose fiber structures are liquid / air permeable, providing little protection from the environment and / or moisture, as well as liquid, fluid, or wet products that may be found inside the dry molded cellulose fiber structures.

[0050] In addition to cardboard, cups, plates, bowls, bottles, and egg packaging mentioned above, the dry molded process may be beneficial in various goods including dairy products (such as cheeses and cheese spreads including cream cheese) beauty and cosmetic products, chilled food, dried foods, coffee, frozen food, personal care products, medical devices, tobacco, and other food and non-food consumer goods. Dry molded cellulose fiber structures may be used in packaging formats such as tubs and lids, blister packs, and trays. However, for many of these uses, the dry molded cellulose fiber structures must have low moisture and / or oxygen transmission characteristics in order to be practical to the contained product. In order to impart desirable low moisture and / or oxygen transmission characteristics, low moisture and / or oxygen transmission layers may be formed on the dry molded cellulose fiber structures.

[0051] A barrier forming system 10 that adds such layers according to a non-limiting example is shown in Fig. 1. The barrier forming system 10 includes a barrier forming assembly 100 that may be operably connected to one or more of a vacuum casing 50, a force generating mechanism assembly 60, a heater assembly 70, and a cooling assembly 90.

[0052] The vacuum casing 50 may be connected to a pump 20 via a vacuum line 53. The pump 20 may be operated to remove gases within the vacuum casing 50 via the vacuum line 53. A vacuum reservoir 30 may be disposed between the vacuum casing 50 and the pump 20, and a first pressure gauge 35 may be operably connected to the vacuum reservoir 30 to monitor the pressure within the vacuum reservoir 30. A vacuum valve 40 may be disposed between the vacuum casing 50 and the pump 20. The vacuum valve 40 may be opened to remove gases from the vacuum casing 50 when the pump 20 is operating and may be closed to seal the vacuum casing 50. The vacuum valve 40 may be disposed between the vacuum reservoir 30 and the vacuum casing 50. The pump 20 may form a vacuum in the vacuum reservoir 30, and the vacuum reservoir 30 may provide quick evacuation of the vacuum casing 50. A second pressure gauge may be connected to the vacuum line 53 between the vacuum valve 40 and the vacuum casing 50 to monitor the pressure in the vacuum line 53 immediately upstream of the vacuum valve 40. A third pressure gauge 55 may be operably connected to the vacuum casing 50 to monitor the pressure within the vacuum casing 50. According to one or more embodiments, a blower may be employed inplace of the pump 20. Fig. 1 only shows a single pump 20, the barrier forming system 10 may include a plurality of pumps 20.

[0053] The force generating mechanism assembly 60 may be connected to an actuator 61. The actuator 61 is operable to actuate the force generating mechanism assembly 60 and may include, e.g., a motor, a gear system, and / or a pressure generating pump. In a barrier forming system 10 in which the force generating mechanism assembly 60 is used to blow mold a barrier material 110 onto the dry molded cellulose fiber structure 120 (see Figs. 10A- 10F), the force generating mechanism assembly 60 may be connected to the pump 20 or another pump to receive air therefrom. An air valve 63 may be disposed between the pump 20 and the force generating mechanism assembly 60. The air valve 63 may be opened to input a flow of air into the force generating mechanism assembly 60 when the pump 20 is operating and may be closed to stop the flow of air into the force generating mechanism assembly 60. The pump 20 may include a single pump or a plurality of pumps. The pump 20 may include multiple pumps located at a single location or multiple locations. The pump 20 may include multiple pumps operable to provide pressure and vacuum force concurrently.

[0054] According to one or more embodiments, the barrier forming system 10 may include a force generating mechanism assembly 60 that has a pressure building mechanism 67 (see Fig. 12) that generates a positive pressure above a barrier material 110. The force generating mechanism assembly 60 may be operably connected to the pump 20 which may generate pressure within the pressure building mechanism 67. Alternatively or additionally, the pressure building mechanism 67 may include its own pump, blower, or fan therein for generating pressure.

[0055] The barrier forming system 10 may further include a controller 80. The controller 80 may include processing circuitry that may include an application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and memory that stores and / or executes one or more software or firmware programs, a combinational logic circuit, and / or other suitable components that provide the described functionality. The controller 80 may be operably connected to the pump 20 to control and / or operate the pump 20. The controller 80 may be operably connected to the vacuum valve 40 and / or the air valve 63 to control and / or operate the vacuum valve 40 and / or the air valve 63. For example, the controller 80 may be operable to open and close the vacuum valve 40 and / or the air valve 63. The controller 80 may be operably connected to the first pressure gauge 35, the second pressure gauge 45, and the third pressure gauge 55 and may be configured to receive data indicating the pressures at one or more of the locations of the first pressure gauge35, the second pressure gauge 45, and the third pressure gauge 55. The data indicating the pressures received from the first pressure gauge 35, the second pressure gauge 45, and / or the third pressure gauge 55 may be used to control the pump 20 and / or the vacuum valve 40. The controller 80 may be operably connected to the actuator 61 to control and / or operate the actuator 61. The controller 80 may be operably connected to the heater assembly 70 to control and / or operate the heater assembly 70. The controller 80 may be operably connected to the cooling assembly 90 to control and / or operate the cooling assembly 90. While not shown, the pump 20 may be connected to the heater assembly 70 and / or the cooling assembly 90 as well to provide airflow.

[0056] Figs. 2-6 demonstrate a barrier forming process according to one or more embodiments. As shown in Fig. 2, the barrier forming assembly 100 includes a barrier material 110 positioned atop a dry molded cellulose fiber structure 120. As a non-limiting example, the barrier material 110 may be a thermoplastic material in the form of a sheet or film. Clamping structures 130 may be positioned on the barrier material 110 at a periphery of the dry molded cellulose fiber structure 120. The clamping structures 130 may clamp the barrier material 110 such that a perimeter of the barrier material 110 is stationary and / or sealed. The clamping structures 130 may clamp the barrier material 110 onto the top wall 58. According to one or more embodiments, an adhesive may be disposed at an upper surface and / or upper flange of the dry molded cellulose fiber structure 120 so that the barrier material 110 adheres to the upper surface or the upper flange of the dry molded cellulose fiber structure 120. The dry molded cellulose fiber structure 120 defines a space 121 therein. In the initial configuration shown in Fig. 2, the barrier material 110 may be disposed above the space 121. The dry molded cellulose fiber structure 120 may be supported by the vacuum casing 50. The vacuum casing 50 may include a bottom wall 56, a plurality of side walls 57, and a top wall 58. According to one or more embodiments, the vacuum casing 50 may have a single annular side wall 57 instead of the side walls 57. The bottom wall 56, the side wall(s) 57, and the top wall 58, together with an outer surface of the dry molded cellulose fiber structure 120, define a vacuum chamber 51. The top wall 58 includes an opening through which the dry molded cellulose fiber structure 120 is inserted into the vacuum casing 50. The bottom wall 56 may include an opening coupled to the vacuum line 53. Alternatively or additionally, the side wall 57 may include an opening coupled to the vacuum line 53. According to one or more embodiments, the opening is formed in the bottom wall 56 at its lowest point.

[0057] As shown in Fig. 2, the heater assembly 70 is positioned over the barrier material 110. The heater assembly 70 may include a heater 71 with a heating element 72. The heater 71 may heat the barrier material 110 via radiation. According to one or more embodiments, the heater assembly 70 may include a fan 73 configured to blow heated air 75 from the heater 71 onto the barrier material 110. The heater assembly 70 heats the barrier material 110 for a period of time such that the barrier material 110 softens. The barrier material 110 may be heated for a period of time until softened and pliable. The barrier material 110, once heated for the period of time, may sag then tighten due to orientation stresses. The period of time for heating the barrier material 110 may include a predetermined period of time that that barrier material 110 is held at the heated state in order to reduce residual orientation stresses. As a non-limiting example, the predetermined period of time may be 15 to 20 seconds. As a non-limiting example, the barrier material 110 may be heated to a temperature in the range of 285-375°F depending on the type and shape of the barrier material 110. Some barrier materials 110 may benefit from being heated to temperatures outside of this range. If the barrier material 110 is thermoplastic, the temperature may be raised to or slightly above a melting temperature thereof. The heater assembly 70 may heat the barrier material 110 via conduction, convection, or radiation. According to one or more embodiments, the heater assembly 70 may include a heat source that emits infrared wavelengths to heat the barrier material 110 via radiation.

[0058] A force generating mechanism assembly 60 may comprise different force generating mechanisms. For example, the force generating mechanism of the force generating mechanism assembly 60 may include a plunger, and / or an air blowing mechanism such as a fan, a blower, or a pump. As shown in Fig. 12, the force generating mechanism of the force generating mechanism assembly 60 may be a pressure building mechanism 67 for building positive pressure above the barrier material 110 such that the pressure difference between a top of the barrier material 110 and a bottom of the barrier material 110 (which may experience a vacuum force) presses the barrier material 110 downward onto the dry molded cellulose fiber structure 120. The pressure generating mechanism 67 may include a pressure chamber, a fan, a blower, or a pressure generating pump.

[0059] As shown in Fig. 3, the force generating mechanism assembly 60 may be moved to a position above the barrier material 110 softened by the heater assembly 70 or the barrier material 110 softened by the heater assembly 70 may be moved to a position below the force generating mechanism assembly 60. The force generating mechanism assembly 60 may include a plunger 65, and a thermal insulation layer 67, a nonstick coating, and / or a lowcoefficient of friction coating may be formed on a portion of the plunger 65 that is configured to contact the barrier material 110 so that the barrier material is not prematurely cooled by the plunger 65, does not stick to the plunger 65, and / or is able to easily slide along the plunger 65. The actuator 61 (see Fig. 1) may actuate the plunger 65 from a raised position shown in Fig. 3 to a lowered position shown in Fig. 4. As the plunger 65 is lowered, the barrier material 110 may be pushed and deformed by the plunger 65 into the space 121 defined by the dry molded cellulose fiber structure 120. The barrier material 110 may be stretched by the plunger 65 to the configuration shown in Fig. 4. The clamping structures 130 may clamp the perimeter of the barrier material 110 such that the perimeter portions of the barrier material 110 do not move while the plunger 65 stretches the barrier material 110. Although Fig. 4 shows the plunger 65 only entering partially into the space 121, according to one or more embodiments, the plunger 65 may be fully inserted into the space 121 such that the barrier material 110 is deformed by the plunger 65 and comes into contact with an inner surface of the dry molded cellulose fiber structure 120. For example, the plunger 65 may correspond to a shape of the dry molded cellulose fiber structure 120 such that the plunger 65 is inserted until the barrier material 110 contacts the dry molded cellulose fiber structure 120. That is, the outer surface of the plunger 65 matches a shape of an inner surface of the dry molded cellulose fiber structure 120. In such a case, an outer surface of the dry molded cellulose fiber structure 120 may be supported, e.g., by a porous support structure 52 shown in Fig. 7.

[0060] As shown in Fig. 5, during or subsequent to lowering of the plunger 65, gases (e.g., air) within the vacuum chamber 51 may be vacuumed via the vacuum line 53 by the pump 20 (see Fig. 1). The perimeter of the barrier material 110 clamped by the clamping structures 130 may form a seal such that the space 121 between the barrier material 110 and the dry molded cellulose fiber structure 120 is sealed. If the dry molded cellulose fiber structure 120 is sufficiently porous, as the gases are vacuumed from the vacuum chamber 51, the gases between the barrier material 110 and the dry molded cellulose fiber structure 120 may be forced through the porous dry molded cellulose fiber structure 120, via atmospheric pressure against a top surface of the barrier material 110, into the vacuum chamber 51 and vacuumed out via the vacuum line 53. If the dry molded cellulose fiber structure 120 is not sufficiently porous, as shown in Fig. 8, small apertures 125 may be formed through the dry molded cellulose fiber structure 120 such that the gas between the barrier material 110 and the dry molded cellulose fiber structure 120 is forced through the apertures 125 into the vacuum chamber 51 and vacuumed out via the vacuum line 53. By vacuuming out the gasesbetween the barrier material 110 and the dry molded cellulose fiber structure 120, the barrier material 110 is pulled flush against a contour of the inner wall of the dry molded cellulose fiber structure 120.

[0061] The barrier material 110 then may be actively cooled as discussed below or allowed to cool. For example, a cooling airflow may be generated and / or directed onto the barrier material 110 via, for example, a fan, a blower, or a pump. As the barrier material 110 cools and hardens, the dry molded cellulose fiber structure 120 conforms and / or adheres partially or completely to the inner wall of the dry molded cellulose fiber structure 120.

[0062] As shown in Fig. 6, the plunger 65 may be raised back up by the actuator 61 (see Fig. 1) and a cooling assembly 90 may be positioned over the barrier material 110. The cooling assembly 90 may include a cooler 91 with a heat exchanger 92. While Fig. 6 shows the heat exchanger 92 being within the cooler 91, the heat exchanger 92 may be disposed outside of the cooler 91 and cool air may be piped to the cooler 91. Alternatively, the cooling assembly 90 may forgo the heat exchanger 92 and instead employ air at environmental temperature. According to one or more embodiments, the cooling assembly 90 may further include a fan 93 configured to blow air 95 from the cooler 91 onto the barrier material 110. The cooling assembly 90 may actively cool the barrier material 110 on the dry molded cellulose fiber structure 120 to conform and / or adhere the barrier material 110 to the dry molded cellulose fiber structure 120. If adhesives are disposed between the barrier material and the dry molded cellulose fiber structure 120, the cooling assembly may cool and harden the adhesive. Alternatively or additionally, cooling may be performed by liquid, e.g., water, to quench film and minimize shrinkback. While the barrier material 110 is being cooled by the cooling assembly 90, the vacuuming force on the barrier material 110 and / or the force on the barrier material 110 from the force generating mechanism assembly 60 may be maintained to maintain a shape of the barrier material 110 on the dry molded cellulose fiber structure 120 until the barrier material 110 is sufficiently solidified and / or crystalized.

[0063] The dry molded cellulose fiber structure 120 with the barrier material 110 conformed and / or adhered thereto may then be removed from the vacuum casing 50. According to one or more embodiments, to facilitate removal of the dry molded cellulose fiber structure 120 with the barrier material 110 from the vacuum casing 50, the pressure within the vacuum chamber 51 may be equalized by either opening the vacuum chamber 51 or by flowing air into the vacuum chamber 51 from the vacuum line 53. Any excess barrier material 110 may then be trimmed from the dry molded cellulose fiber structure 120. Due to the barrier forming process, the barrier material 110 may be thinner conformed and / oradhered to the dry molded cellulose fiber structure 120 than before the barrier forming process.

[0064] According to one or more embodiments, a barrier forming process may include loading the barrier material 110 above the dry molded cellulose fiber structure 120, heating the barrier material 110, conforming and / or adhering the barrier material 110 onto the dry molded cellulose fiber structure 120, cooling the barrier material 110, removing the dry molded cellulose fiber structure 120 with the barrier material 110 conformed and / or adhered thereon, and / or trimming excess barrier material 110.

[0065] Fig. 7 shows a non-limiting example in which the dry molded cellulose fiber structure 120 is supported by a porous support structure 52 of the vacuum casing 50. According to one or more embodiments, the porous support structure 52 may be a mesh structure such that air can pass therethrough while able to support the dry molded cellulose fiber structure 120. According to one or more embodiments, the porous support structure 52 may be shaped to correspond to an outer surface of the dry molded cellulose fiber structure 120 to support the dry molded cellulose fiber structure 120 such that the dry molded cellulose fiber structure 120 is evenly supported during the barrier forming process.

[0066] During the heating and forming process set forth above, the pump 20, the vacuum valve 40, the actuator 61, and the heater assembly 70 may be controlled by the controller 80 so as to avoid burnthrough and pinholing of the barrier material 110. Additionally, the heater assembly 70 may be controlled by the controller 80 to release built-in stresses from the manufacturing process of the barrier material 110 achieve low orientation thereof. According to one or more embodiments, the barrier material 110 may be multilayered thermoplastic films or sheets to provide customized properties. According to one or more embodiments, the barrier material 110 be disposed on the dry molded cellulose fiber structure 120 as a colored thermoplastic film or sheet, as the barrier forming system 10 and process described above allows for the use of colored thermoplastic film or sheet.

[0067] The pump 20, the vacuum reservoir 30, the first pressure gauge 35, the vacuum valve 40, the second pressure gauge, the vacuum casing 50, the vacuum chamber 51, the porous support structure 52, the vacuum line 53, and the third pressure gauge 55 may collectively define a vacuum system. The vacuum system may omit one or more of the above elements, as long as the vacuum system may generate vacuum flow.

[0068] The barrier forming system 10 may move the heater 70, the force generating mechanism assembly 60, and the cooling assembly 90 to and from a vacuum casing 50, a barrier material 110, and a dry molded cellulose fiber structure 120 that are stationary, ormove the vacuum casing 50, the barrier material 110, and the dry molded cellulose fiber structure 120 to and from the barrier forming system 10 and the heater 70 that are stationary, or a combination thereof.

[0069] Figs. 9A-9C show a barrier forming process according to one or more embodiments. As shown in Fig. 9A, the barrier material 110 may be overlaid on the dry molded cellulose fiber structure 120. As shown in Fig. 9B, heated air may be blown onto a top surface of the barrier material 110 to thereby soften the barrier material 110. Pressure forming air may then be impinged onto the top surface of the and push the barrier material 110 onto the dry molded cellulose fiber structure 120. A vacuum may also be applied to a lower portion of the dry molded cellulose fiber structure 120 to pull the barrier material 110 to the dry molded cellulose fiber structure 120 similarly to one or more of the above embodiments. As shown in Fig. 9C, excess portions of the barrier material 110 may be cut from the dry molded cellulose fiber structure 120.

[0070] Figs. 10A-10F show a barrier forming process according to one or more embodiments. As shown in Fig. 10A, the barrier material 110 may be formed as a preform. According to one or more embodiments, the barrier material 110 may be preheated. The barrier material 110 is placed within the dry molded cellulose fiber structure 120 which may be, but is not limited to, a bottle. The force generating mechanism assembly 60 may be a stretch rod with one or more air injection holes formed therethrough and connected to the pump 20 (see Fig. 1). The force generating mechanism assembly 60 stretches the preform longitudinally from the configuration shown in Fig. 10A to the configuration shown in FIG. 10B. As the force generating mechanism assembly 60 is lowered further into the dry molded cellulose fiber structure 120, air is blown into the barrier material 110 through the air injections holes in the force generating mechanism assembly 60 to apply internal pressure and circumferentially stretch the barrier material 110 as shown in Figs. 10C and 10D. The air is continually injected into the barrier material 110 through the air injection holes in the force generating mechanism assembly 60 as shown in Fig. 10E. A vacuum may also be applied to a lower portion of the dry molded cellulose fiber structure 120 to pull the barrier material 110 to the dry molded cellulose fiber structure 120 similarly to one or more of the above embodiments. The barrier material 110 may conform and / or adhere to an inner surface of the dry molded cellulose fiber structure 120 as shown in Fig. 10F. The force generating mechanism assembly 60 is then removed from the barrier material 110, and the barrier material 110 is actively cooled or allowed to cool such that the barrier material 110 is conformed and / or adhered to the dry molded cellulose fiber structure 120.

[0071] As the dry molded cellulose fiber structure 120 may have a low heat transfer coefficient, i.e., be an insulator, cooling air may be blown onto the barrier material 110 to help the cooling process. For example, a fan, a blower, or a pump may generate cooling airflow onto the barrier material 110. According to one or more embodiments, the barrier forming system 10 and process may maintain the forming force (e.g., vacuuming the vacuum chamber 51 via the vacuum line 53) until the barrier material 110 is conformed and / or adhered to the dry molded cellulose fiber structure 120, which may be especially beneficial if the barrier material 110 is highly oriented.

[0072] Molecules of the barrier material 110 may be oriented during the manufacturing process of the barrier material 110. When heated, the oriented molecules of the barrier material 110 want to return to an unoriented state. Thus, the orientation may create issues after forming. For example, the barrier material 110 may shrink due to retained stresses. The controller 80 may control the heating and cooling process to reduce retained stresses within the barrier material 110. Furthermore, the barrier material 110 may be heat treated prior to the process described above to reduce retained stresses. According to one or more embodiments, barrier material 110 with low orientation, e.g. a thermoplastic sheet, may be selected.

[0073] While the above description involves adding barrier material 110 to an inside surface of the dry molded cellulose fiber structure 120, as shown in Fig. 11, a similar system and process may be employed to add barrier material 110 to an outer surface of the dry molded cellulose fiber structure 120 as well. While having the barrier material 110 on the inner surface of the dry molded cellulose fiber structure 120 may be sufficient for products held within the dry molded cellulose fiber structure 120, the barrier material 110 on the outer surface of the dry molded cellulose fiber structure 120 may be beneficial to protect the dry molded cellulose fiber structure 120 from the environment. The dry molded cellulose fiber structure 120 may be supported on the vacuum casing 50 via a porous support structure 52. The barrier material 110 may be positioned over an outside surface of the dry molded cellulose fiber structure 120 and perimeter portions of the barrier material 110 may be clamped by a clamping structure 130. Similarly to the embodiment shown in Fig. 2, a heater assembly 70 may heat the barrier material 110. If the dry molded cellulose fiber structure 120 does not have barrier material 110 on an inner surface thereof, a vacuum may be applied to the inner surface of the dry molded cellulose fiber structure 120 to pull the barrier material 110 onto an outer surface of the dry molded cellulose fiber structure 120. For example, a pump 20 may be operated to remove gases within vacuum chamber 51 of the vacuum casing50 via the vacuum line 53, forming a vacuum in the vacuum chamber 51 and the space 121 within the dry molded cellulose fiber structure 120. As the dry molded cellulose fiber structure 120 may be porous or have drilled holes, the vacuum within the space 121 pulls the barrier material 110 towards an outer surface of the dry molded cellulose fiber structure 120, conforming and / or adhering the barrier material 110 to the outer surface of the dry molded cellulose fiber structure 120. A gap may be formed between the top wall 58 and the dry molded cellulose fiber structure 120 so that a vacuum may also be formed between the outer surface of the dry molded cellulose fiber structure 120 and an inner surface of the barrier material 110 to help move the barrier material 110 towards the dry molded cellulose fiber structure 120 and conform and / or adhere the barrier material 110 to the dry molded cellulose fiber structure 120. Similarly to the embodiment shown in Fig. 6, the barrier material 110 may then be cooled by a cooling assembly 90 to conform and / or adhere the barrier material 110 to the dry molded cellulose fiber structure 120.

[0074] Alternatively, the dry molded cellulose fiber structure 120 itself may be employed as a plunger and actuated down onto a barrier material 110 that has been heated and stretched over a cavity. A vacuum may be applied to the dry molded cellulose fiber structure 120 on a side opposite the barrier material 110 to conform and / or adhere the barrier material 110 to the dry molded cellulose fiber structure 120. For example, the dry molded cellulose fiber structure 120 may be positioned on a plunger with one or more vacuum air vents to vacuum out the gas between the dry molded cellulose fiber structure 120 and the barrier material 110. The vacuuming may be performed while the dry molded cellulose fiber structure 120 is being inserted into the barrier material 110.

[0075] According to one or more embodiments, primer or adhesive may be applied to the dry molded cellulose fiber structure 120 to help the barrier material 110 adhere to its surface.

[0076] While the barrier forming system 10 and process described above involves forming the barrier material 110 on the dry molded cellulose fiber structure 120 after the dry molded cellulose fiber structure 120 is formed, according to one or more embodiments, the barrier material 110 may be added to a cellulose fiber sheet as the dry molded cellulose fiber structure 120 is formed. This may be done when the dry molded cellulose fiber structure 120 has a shallow draw, such as a plate or shallow cardboard products. The barrier material 110 may be added by extrusion coating or lamination. Such a process may involve a mold cooling system.

[0077] A container such as one formed via a wet forming process has to be removed from a mold. There are structures such as undercuts and diameters that increase towards the bottom of the container that would prevent removal from the mold. In contrast, the barrier material 110 is not removed from the dry molded cellulose fiber structure 120 and, as such, the dry molded cellulose fiber structure 120 with the barrier material 110 may have undercuts and diameters that increase towards the bottom of the container. The undercuts may provide mechanical locking between the barrier material 110 and the dry molded cellulose fiber structure 120 to further conform and / or adhere the barrier material 110 to the dry molded cellulose fiber structure 120.

[0078] The barrier forming system 10 and barrier forming process described above may result in a dry molded cellulose fiber structure 120 with a barrier material 110 formed thereon. The barrier material 110 may provide water-resistant or water-proof characteristics to the dry molded cellulose fiber structure 120. Additionally, the barrier material 110 may improve mechanical properties of the dry molded cellulose fiber structure 120, e.g., the strength thereof. The dry molded cellulose fiber structure 120 with the barrier material 110 formed according to the barrier forming system 10 and process described above may be heat sealable, recyclable, biodegradable and compostable with use of biodegradable plastics, and may be made mostly with renewable resources. According to one or more embodiments, the dry molded cellulose fiber structure 120 serves as a mold for the barrier material 110 such that a separate mold for the barrier material 110 is not required. As the dry molded cellulose fiber structure 120 may be an insulator, the dry molded cellulose fiber structure 120 with the barrier material 110 formed thereon may be microwave friendly.

[0079] The terms “a” and “an” do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. The term “or” means “and / or” unless clearly indicated otherwise by context. Reference throughout the specification to “an aspect”, means that a particular element (e.g., feature, structure, step, or characteristic) described in connection with the aspect is included in at least one aspect described herein, and may or may not be present in other aspects. In addition, it is to be understood that the described elements may be combined in any suitable manner in the various aspects.

[0080] When an element such as a layer, film, region, or substrate is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present.

[0081] Unless defined otherwise, technical, and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art to which this disclosure belongs.

[0082] While the above disclosure has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from its scope. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure without departing from the essential scope thereof. Therefore, it is intended that the present disclosure not be limited to the particular embodiments disclosed, but will include all embodiments falling within the scope thereof.

Claims

CLAIMSWhat is claimed is:

1. A barrier forming system for a dry formed cellulose fiber container, comprising: a support structure configured to support a dry formed cellulose fiber structure; a barrier material disposed proximate the support structure; and a force generating mechanism configured to move at least one of the barrier material and the dry formed cellulose fiber structure into contact with each other.

2. The barrier forming system of claim 1, further comprising a vacuum system configured to vacuum out gas between the barrier material and the dry formed cellulose fiber structure such that the barrier material conforms to the dry formed cellulose fiber structure.

3. The barrier forming system of claim 2, wherein the support structure is a vacuum casing.

4. The barrier forming system of claim 3, wherein the vacuum casing is operable to be connected to a pump or a blower of the vacuum system that vacuums out gas within the vacuum casing to force the gas between the barrier material and the dry formed cellulose fiber structure through the dry formed cellulose fiber structure.

5. The barrier forming system of claim 1, further comprising a heater assembly configured to heat the barrier material prior to vacuuming out the gas between the barrier material and the dry formed cellulose fiber structure.

6. The barrier forming system of claim 5, wherein the heater assembly comprises a heating element configured to radiate infrared wavelengths to heat the barrier material.

7. The barrier forming system of claim 1, wherein the force generating mechanism assembly comprises a plunger assembly configured to push a portion of the barrier material towards the dry formed cellulose fiber structure or the dry formed cellulose fiber structure towards the barrier material.

8. The barrier forming system of claim 7, wherein the plunger assembly comprises a plunger operably connected to an actuator that is configured to actuate the plunger towards the barrier material.

9. The barrier forming system of claim 7, wherein the plunger assembly comprises a plunger having an insulated surface configured to contact the barrier material.

10. The barrier forming system of claim 7, wherein the plunger assembly comprises a plunger having one or more air injection holes formed therein.

11. The barrier forming system of claim 10, wherein the plunger assembly is operably connected to a pump or a blower configured to inject air through the one or more air injection holes towards the barrier material.

12. The barrier forming system of claim 1, wherein the barrier material is a thermoplastic sheet or film.

13. A method for forming a dry formed cellulose fiber container, the method comprising: placing a barrier material proximate a dry formed cellulose fiber structure, and allowing the barrier material to conform to the dry formed cellulose fiber structure.

14. The method of claim 13, further comprising heating the barrier material via a heater assembly.

15. The method of claim 13, further comprising moving the barrier material towards the cellulose fiber structure or moving the cellulose fiber structure towards the barrier material via a plunger assembly.

16. The method of claim 13, further comprising vacuuming out gas between the barrier material and the dry formed cellulose fiber structure through the dry formed cellulose fiber structure.

17. The method of claim 14, wherein the barrier material is heated to a predetermined temperature and held at the predetermined temperature for a predetermined period to reduce residual orientation stresses.

18. The method of claim 14, wherein the heater assembly heats the barrier material via infrared wavelength radiation.

19. The method of claim 15, wherein air is injected towards the barrier material via one or more air injection holes formed in a plunger of the plunger assembly.

20. The method of claim 13, wherein the barrier material is a thermoplastic sheet or film.

21. The method of claim 13, further comprising: heating the barrier material via a heater assembly; moving the barrier material heated by the heater assembly towards the cellulose fiber structure or moving the cellulose fiber structure towards the barrier material heated by the heater assembly; vacuuming out gas between the barrier material and the dry formed cellulose fiber structure through the dry formed cellulose fiber structure; and cooling the barrier material such that the barrier material conforms to the cellulose fiber structure.

22. A dry formed cellulose fiber container formed by a method comprising:placing a barrier material proximate a dry formed cellulose fiber structure, and allowing the barrier material to conform to the dry formed cellulose fiber structure.

23. The barrier forming system of claim 1, wherein the barrier forming system is configured to adhere the barrier material to the dry formed cellulose fiber structure.

24. The barrier forming system of claim 23, wherein the barrier forming system is configured to dispose adhesive onto the dry formed cellulose fiber structure to adhere the barrier material to the dry formed cellulose fiber structure.

25. The barrier forming system of claim 1, further comprising a clamping structure configured to clamp a perimeter of the barrier material to be stationary.

26. The barrier forming system of claim 25, wherein the clamping structure forms a seal at the perimeter of the barrier material.

27. The barrier forming system of claim 2, wherein apertures are formed in the dry formed cellulose fiber structure to transmit vacuum through the dry formed cellulose fiber structure.

28. The barrier forming system of claim 1, wherein the force generating mechanism comprises a pressure generating mechanism that generates a positive pressure on the barrier material to push the barrier material towards the dry formed cellulose fiber structure.

29. The barrier forming system of claim 1, further comprising a cooling assembly configured to cool the barrier material.

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