Classifications

• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21J—FIBREBOARD; MANUFACTURE OF ARTICLES FROM CELLULOSIC FIBROUS SUSPENSIONS OR FROM PAPIER-MACHE
  • D21J3/00—Manufacture of articles by pressing wet fibre pulp, or papier-mâché, between moulds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65B—MACHINES, APPARATUS OR DEVICES FOR, OR METHODS OF, PACKAGING ARTICLES OR MATERIALS; UNPACKING
  • B65B47/00—Apparatus or devices for forming pockets or receptacles in or from sheets, blanks, or webs, comprising essentially a die into which the material is pressed or a folding die through which the material is moved
  • B65B47/04—Apparatus or devices for forming pockets or receptacles in or from sheets, blanks, or webs, comprising essentially a die into which the material is pressed or a folding die through which the material is moved by application of mechanical pressure
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65B—MACHINES, APPARATUS OR DEVICES FOR, OR METHODS OF, PACKAGING ARTICLES OR MATERIALS; UNPACKING
  • B65B5/00—Packaging individual articles in containers or receptacles, e.g. bags, sacks, boxes, cartons, cans, jars
  • B65B5/02—Machines characterised by incorporation of means for making the containers or receptacles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65B—MACHINES, APPARATUS OR DEVICES FOR, OR METHODS OF, PACKAGING ARTICLES OR MATERIALS; UNPACKING
  • B65B7/00—Closing containers or receptacles after filling
  • B65B7/16—Closing semi-rigid or rigid containers or receptacles not deformed by, or not taking-up shape of, contents, e.g. boxes or cartons
  • B65B7/28—Closing semi-rigid or rigid containers or receptacles not deformed by, or not taking-up shape of, contents, e.g. boxes or cartons by applying separate preformed closures, e.g. lids, covers
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H11/00—Pulp or paper, comprising cellulose or lignocellulose fibres of natural origin only
  • D21H11/16—Pulp or paper, comprising cellulose or lignocellulose fibres of natural origin only modified by a particular after-treatment
  • D21H11/18—Highly hydrated, swollen or fibrillatable fibres

Definitions

• the present disclosure generally relates to a novel processing method of molding cellulose nanofibril (CNF) and carboxymethyl cellulose (CMC) onto a molded pulp and specifically to a process of co-molding or overmolding CNF/CMC onto a molded pulp.
• CNF cellulose nanofibril
• CMC carboxymethyl cellulose
• CNM such as CNF were first isolated through homogenization of bleached cellulose pulp in the early 1980s.
• a method of overmolding an object of interest with a protective coating includes receiving a mold having a top half and a bottom half dimensioned for an object of interest, placing the object of interest into the bottom half of the mold, spreading a layer or laying a sheet of a mixture cellulose nanofibril (CNF) and carboxymethyl cellulose (CMC) on to the object of interest, placing the top half of the mold onto the CNF/CMC layer, applying a predetermined pressure between the top and bottom halves of the mold, applying a predetermined amount of heat to the mold, to thereby molding the CNF/CMC mixture onto the object of interest, and removing the object of interest with the layer of CNF/CMC formed thereon from the mold a predetermined amount of time.
• CNF cellulose nanofibril
• CMC carboxymethyl cellulose
• the object of interest is a molded pulp.
• the molded pulp is a food carton.
• the molded pulp is a pharmaceutical carton.
• the mixture of CNF/CMC has a CMC to CNF weight ratio range of between about 0.03:1 to about 0.3:1.
• the weight ratio range is between about 0.03:1 to about 0.2:1. [0014] In the above method, the weight ratio range is between about 0.03:1 to about 0.1:1. [0015] In the above method, the weight ratio range is between about 0.05:1 to about 0.2:1.
• the weight ratio range is between about 0.05:1 to about 0.15:1.
• the weight ratio range is between about 0.1:1 to about 0.2:1.
• the weight ratio range is between about 0.1:1 to about 0.15:1.
• the CNF/CMC coated object of interest can withstand about 3X higher stress as compared to an uncoated object of interest prior to onset of plastic deformation.
• the CNF/CMC coated object of interest can withstand about 1.6X higher load as compared to an uncoated object of interest prior to being crushed.
• the CNF/CMC coated object of interest has a kit grease resistance value of 6 to 8 as compared to an uncoated object of interest with a kit value of 1.
• the CNF/CMC coated object of interest has 20% or more higher resistance to moisture as compared to an uncoated object of interest as measured by WVTR.
• the top half of the mold includes a plurality of through -holes.
• the bottom half of the mold includes a plurality of through- holes.
• the predetermined pressure is about 1.5 KPa.
• the predetermined amount of heat causes the mold to reach between about 70 °C and about 110 °C.
• the primer or bonding agent comprises chitosan, cationic starch, and starch.
• the above method further includes placing an item of interest in the object of interest with the layer of CNF/CMC formed thereon, and lidding the item of interest with a pliable wrap.
• the pliable wrap is selected from the group consisting of polyethylene terephthalate (PET), polypropylene, polylactic acid (PLA), and a combination thereof.
• the pliable wrap is made from low-density polyethylene (LDPE).
• LDPE low-density polyethylene
• LDPE includes linear low-density polyethylene as an additive.
• the pliable wrap is made from a bio-degradable material.
• the mixture of CNF/CMC further includes additives selected from the group consisting of polyvinylalcohol, starch, polyacrylamides, polyaziridine, polyamidoamine-epichlorohydrins, polycarbodiimides, ammonium zirconium carbonate, alkyl ketene dimers, silanes, anhydrides, and a combination thereof.
• Another method of co-molding an object of interest with a protective coating includes receiving a mold having a top half and a bottom half dimensioned for an object of interest, placing a moldable material constituting raw material for the object of interest into the bottom half of the mold, spreading a layer or laying a sheet of a mixture of cellulose nanofibril (CNF) and carboxymethyl cellulose (CMC) on to the moldable material, placing the top half of the mold onto the CNF/CMC layer, applying a predetermined pressure between the top and bottom halves of the mold, applying a predetermined amount of heat to the mold, to thereby simultaneously molding both the object of interest and the CNF/CMC layer thereon, and removing the molded object of interest with the CNF/CMC layer formed thereon from the mold after a predetermined amount of time.
• CNF cellulose nanofibril
• CMC carboxymethyl cellulose
• the moldable material for the object of interest is a slurry of a fibrous pulp.
• the mixture of CNF/CMC further includes additives selected from the group consisting of polyvinylalcohol, starch, polyacrylamides, polyaziridine, polyamidoamine-epichlorohydrins, polycarbodiimides, ammonium zirconium carbonate, alkyl ketene dimers, silanes, anhydrides, and a combination thereof.
• the object of interest is a molded pulp.
• the molded pulp is a food carton.
• the molded pulp is a pharmaceutical carton.
• the mixture of CNF/CMC has a CMC to CNF weight ratio range of between about 0.03:1 to about 0.3:1.
• the weight ratio range is between about 0.03:1 to about 0.2:1.
• the weight ratio range is between about 0.03:1 to about 0.1:1.
• the weight ratio range is between about 0.05:1 to about 0.2:1.
• the weight ratio range is between about 0.05:1 to about 0.15:1.
• the weight ratio range is between about 0.1:1 to about 0.2:1.
• the weight ratio range is between about 0.1:1 to about 0.15:1.
• the CNF/CMC coated object of interest can withstand about 3X higher stress as compared to an uncoated object of interest prior to onset of plastic deformation. [0049] In the above method, the CNF/CMC coated object of interest can withstand about 1.6X higher load as compared to an uncoated object of interest prior to being crushed.
• the CNF/CMC coated object of interest has a kit grease resistance value of 6 to 8 as compared to an uncoated object of interest with a kit value of 1.
• the CNF/CMC coated object of interest has 20% or more higher resistance to moisture as compared to an uncoated object of interest as measured by WVTR.
• the top half of the mold includes a plurality of through -holes.
• the predetermined pressure is between about 10 KPa to about 10 MPa.
• the predetermined amount of heat causes the mold to reach between 50 °C and 400 °C.
• the primer or bonding agent comprises chitosan, cationic starch, and starch.
• the above method further includes placing an item of interest in the object of interest with the layer of CNF/CMC formed thereon, and lidding the item of interest with a pliable wrap.
• the pliable wrap is selected from the group consisting of polyethylene terephthalate (PET), polypropylene, polylactic acid (PLA), and a combination thereof.
• PET polyethylene terephthalate
• PLA polylactic acid
• the pliable wrap is made from low-density polyethylene (LDPE).
• LDPE low-density polyethylene
• the pliable wrap is made from a bio-degradable material.
• FIG. 1 is a cross-sectional view of one embodiment of a mold apparatus used in the present disclosure.
• FIG. 2 provides photographs of a flow of steps disclosed in the present disclosure.
• FIG. 3 is a photograph of an example of mold halves of an example of FIG. 1 with holes provided in both halves for improved breathability of the molding process.
• FIG. 4 is a bar graph of Water Vapor Transport Rate (WVTR) in g/cm 2 -d vs. time in days showing results from coated molded pulp (MP) in dry form vs. coated MP in wet form vs. uncoated MP in dry form vs. uncoated MP in wet form.
• WVTR Water Vapor Transport Rate
• FIG. 5 is a graph of stress (MPa) vs strain (%) curves for coated and uncoated MP samples in uniaxial tensile testing.
• FIG. 6A is a graph of load in N vs. strain in % for five pulp samples in an uncoated state showing stress capabilities of the pulp without coating.
• FIG. 6B is a graph of load in N vs. strain in % for five pulp samples in a coated state showing stress capabilities of the molded pulp with coating.
• the term “about” can allow for a degree of variability in a value or range, for example, within 10%, within 5%, or within 1% of a stated value or of a stated limit of a range.
• the term “substantially” can allow for a degree of variability in a value or range, for example, within 90%, within 95%, or within 99% of a stated value or of a stated limit of a range.
• CNF cellulose nanofibril
• CMC carboxymethyl cellulose
• the protective layer provides numerous benefits to the object of interest, including i) protection against oxygen and oxygen radical transference from outside to interior compartments (thereby allowing the protected object to be used for preserving foods or pharmaceuticals in the associated protected package); ii) providing a moisture barrier from outside to inside or from inside to outside; iii) providing a grease barrier from outside to inside or from inside to outside; and iv) further stiffening the object.
• CNF/CMC The composition of CNF/CMC is of particular importance.
• a CMC to CNF weight ratio range of 0.03:1 to 0.3:1 is utilized.
• the range is 0.03:1 to 0.2:1, 0.03:1 to 0.1:1, 0.05:1 to 0.2:1, 0.05:1 to 0.15:1, 0.1:1 to 0.2:1, or 0.1:1 to 0.15 : 1.
• a preferred ratio is about 0.1:1.
• the present disclosure provides a molding apparatus and method to prepare an over-molded material comprising CNF and CMC, wherein the method comprises: providing a homogenous mixture comprising CNF and CMC, wherein the homogenous mixture has a solid content of 10-30 wt. %, and the homogenous mixture has a CMC/CNF weight ratio range of 0.03:1 to 0.3:1.
• the range is 0.03:1 to 0.2:1, 0.03:1 to 0.1:1, 0.05:1 to 0.2:1, 0.05:1 to 0.15:1, 0.1:1 to 0.2:1, or 0.1:1 to 0.15:1.
• a preferred ratio is about 0.1:1.
• the method also includes generating a mold for the object; loading the object onto the generated mold, loading the homogenous mixture comprising CNF and CMC onto the object which is loaded onto the mold; and molding the homogenous mixture comprising CNF and CMC to provide a material with the desired shape of the object.
• the present methodology deals with overmolding moldable CNF/CMC onto molded pulp to generate a package suitable for food that is fully compostable and degradable made of sustainable cellulose which benefits from the above-enumerated advances.
• Cellulose is abundant in nature and can be extracted from many sources. Additionally, cellulose also has an inherent requisite thermal barrier and mechanical properties necessary for packaging in many industries. Advantageously, nanocellulose has been already extracted at industrial scale.
• the overmolding apparatus 100 includes a manufactured bottom mold 102 configured to form-fit outside shape of an object of interest 112, e.g., a molded pulp, e.g., an egg carton.
• the overmolding apparatus 100 further includes an optional layer of a primer or bonding agent 110 (e.g., Chitosan/ AcOH).
• a primer or bonding agent 110 e.g., Chitosan/ AcOH.
• the optional layer of primer or bonding agent 110 can be avoided.
• the optional layer of primer or bonding agent 110 may be necessary.
• the overmolding apparatus 100 further includes a layer of CNF/CMC 108 that is placed on top of either the object of interest 112 or the layer of primer or bonding agent 112.
• the layer of CNF/CMC 108 is placed down in the form of a sheet over the aforementioned structure (i.e., just the object of interest 112 or the combination of the object of interest 112 and the layer of primer or bonding agent 110).
• the overmolding apparatus 100 includes a manufactured top mold 104 configured to form-fit the above-described structure (i.e., the combination of the object of interest 112 and the layer of CNF/CMC 108 or the combination of the object of interest 112, the layer of primer or bonding agent 110, and the layer of CNF/CMC 108).
• the top mold 104 and the bottom mold 102 provide a sandwich-like configuration for the overmolding apparatus 100 as shown in FIG. 1, thereby providing a predetermined molding pressure and temperature to the structure shown in the overmolding apparatus 100 of FIG. 1.
• the top mold 104 is manufactured with holes 106 provided therein to allow escaping of water molecules during the molding operation.
• the bottom mold 102 can optionally be provided with holes 106 for improved drying.
• a BRAB ENDER mixer is used to make a CNF/CMC paste (with a solid concentration of about 18 wt.% in a solution, e.g., water or other solutions as known to a person having ordinary skill in the art, however a range of about 10% to about 30% is also within the scope of the present disclosure).
• CMC Carboxymethyl cellulose sodium salt powder
• PDC mechanically fibrillated CNFs produced at the PROCESS DEVELOPMENT CENTER
• CNF/CMC pastes with a solid concentration of about 18 wt.% were prepared using a high shear torque mixer (Plasti-Corder PL 2100 Electronic Torque Rheometer, C. W. BRABENDER, South Hackensack NJ) equipped with Banbury-type mixing blades.
• the CNF/CMC pastes were prepared by first adding 52 g of CNF with a solid concentration of about 23.5 wt % into the mixer. The added CNF was mixed at 120 rpm and a temperature of 60 °C until the output torque curve reached a plateau.
• the required amount of processing aid was gradually added until a ratio of 0.1 : 1 was reached (CMC/CNF, both dry weight), however, above-mentioned ratios are within the ambit of the present disclosure.
• Water was also added as needed into the paste to control the final solids concentration and replace the lost water during mixing (-1 wt.% solids increase for a mixing time of 40 min).
• the rotor speed was held at 120 rpm.
• the paste was mixed until the CMC was fully incorporated into the paste which was signaled by a constant rise in torque followed by a plateau region. Utilizing this example method, an average -66 grams of CNF/CMC paste could be processed in less than an hour.
• the above description of making the CNF/CMC paste is only one example, and no limitation is intended thereby.
• the paste of CNF/CMC is made, using a rolling pin or slip roller, the paste is pressed into a CNF/CMC film with a predetermined thickness (about 1 mm).
• the inner wall of the object of interest e.g., a molded pulp, e.g., an egg carton
• a primer or bonding agent is processed with a primer or bonding agent.
• the inner wall is smeared with chitosan/10% acetic acid (aq)/water solution, weight ratio 2:8:90, however, other primers or bonding agents known to a person having ordinary skill in the art are also within the scope of the present disclosure.
• the thin film of CNF/CMC as described above is placed on the top of the inner side of the tray, use fingers to flatten the folded part, remove any leftover materials with a blade. Care must be taken to properly squeeze out the air between the wet sheet and the inner wall of the tray. Additionally, some water can be sprayed on the top of the wet sheet and smeared evenly.
• the processed object is placed inside the mold halves. The mold halves are then secured with a securement providing a predetermined mold pressure to the structure. Next the secured mold haves are placed in an oven heated to about 90 °C for about 6 hrs, depending on the object of interest 112 (e.g., a molded pulp).
• FIG. 3 a photograph of an example of the mold halves is shown with holes provided in both halves for improved breathability of the molding process.
• starch glue can be smeared on the edge of object.
• FIG. 5 is a graph of stress (MPa) vs strain (%) curves for coated and uncoated MP samples in uniaxial tensile testing. In all coated sample cases, it is observed from the figure a much higher stress (about 16-17 MPa) before plastic deformation occurs in the form of breakage as compared to uncoated sample which can only withstand about 5-6 Mpa prior to plastic deformation. Thus, the difference between the two scenarios is about 3X.
• FIG. 6A is a graph of load (N) vs. strain for five uncoated samples; while FIG. 6B is the same graph for the same samples but coated.
• the crushing force for the coated samples is about 400 N whereas the crushing force for uncoated samples is about 250 N.
• the difference between the two scenarios is about 3X.
• the composition and thickness of the coating and MP is provided in Table 1.
• a 3-dimensional digital map including depth information from an object of interest is needed.
• This digital pattern can be generated via a 3-dimensional laser scanning process, known to a person having ordinary skill in the art, an example of which is provided in U.S. Pat. No. 10,353,055 to Moon et al, incorporated by reference in its entirety into the present disclosure.
• the present disclosure is mainly related to an overmolding process of an object of interest that has already been molded (e.g., an egg carton), i.e., an already molded object of interest is placed in the overmolding apparatus shown in FIG. 1, in order to improve the durability, strength, and general quality of the object of interest
• the teachings of the present disclosure can also be applied to co-molding an object of interest with CNF/CMC at the same time, instead of a post-processing approach.
• a co-molding apparatus similar to the one shown in FIG. 1 is provided having a top half and a bottom half that is dimensioned for the object of interest.
• a moldable material constituting raw material for the object of interest is then placed into the bottom half of the mold.
• a layer or laying a sheet of a mixture of CNF/CMC is placed on to the moldable material, e.g., by spreading said CNF/CMC onto the moldable material.
• the top half of the mold is placed onto the CNF/CMC layer.
• a predetermined pressure is applied between the top and bottom halves of the mold while applying a predetermined amount of heat to the mold, to thereby simultaneously mold both the object of interest and the CNF/CMC layer thereon.
• the molded object of interest with the CNF/CMC layer formed thereon is then removed from the mold.
• the mixture of CNF/CMC according to the present disclosure may further include additives selected from the group consisting of polyvinylalcohol, starch, polyacrylamides, polyaziridine, polyamidoamine-epichlorohydrins, polycarbodiimides, ammonium zirconium carbonate, alkyl ketene dimers, silanes, anhydrides, and a combination thereof.
• an item of interest may be placed in the object of interest with the layer of CNF/CMC formed thereon via the overmolding process or the co-molding process, and further lidding the item of interest with a pliable wrap.
• the pliable wrap is selected from the group consisting of polyethylene terephthalate (PET), polypropylene, polylactic acid (PLA), and a combination thereof.
• PET polyethylene terephthalate
• PDA polylactic acid
• the pliable wrap may also be made from low-density polyethylene (LDPE), wherein LDPE includes linear low-density polyethylene as an additive.
• LDPE low-density polyethylene
• the pliable wrap is made further be alternatively be made from only bio-degradable material.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Manufacturing & Machinery (AREA)
• Laminated Bodies (AREA)
• Moulding By Coating Moulds (AREA)
• Wrappers (AREA)
• Casting Or Compression Moulding Of Plastics Or The Like (AREA)

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• 2023
  • 2023-02-15 EP EP23760540.7A patent/EP4483012A4/de active Pending
  • 2023-02-15 CA CA3243511A patent/CA3243511A1/en active Pending
  • 2023-02-15 AU AU2023224020A patent/AU2023224020A1/en active Pending
  • 2023-02-15 WO PCT/US2023/013169 patent/WO2023163888A2/en not_active Ceased
  • 2023-02-15 MX MX2024009683A patent/MX2024009683A/es unknown
  • 2023-02-15 US US18/835,723 patent/US20250145322A1/en active Pending

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