Patent Application
20230404991
The present disclosure relates generally to a fibrous pellet used for the absorption of fluids or the release of fluids in the oral cavity.
Fibrous pellets can be used in various oral applications such as delivering active ingredients, i.e. as nicotine in the case of nicotine pouches or snus, as well as in the medical field for absorbing fluids in the oral cavity. Traditionally, pellets for oral applications are in a “rolled” or “spun” form. These traditional pellets may easily become unraveled and leave fibers behind in the oral cavity. Another issue with the traditional pellets is the inability to properly manage fluid intake and release. The manufacturing process can result in a drastic size and weight variability amongst pellets. Further, the process is not scalable and provides no opportunity to improve the mechanical properties of the pellet.
Therefore, there is a need for an improved fibrous pellet product for oral applications and an improved method of manufacturing said fibrous pellet product.
In view of the above, it is an object of the present disclosure to provide a fibrous pellet with improved and tunable properties, as well as an improved method of manufacturing said fibrous pellets to tune the mechanical and fluid management properties.
In one aspect, a fibrous pellet is disclosed. The fibrous pellet comprising a plurality of fibers oriented linearly relative to the X axis, Y axis, and Z axis. In some embodiments, the plurality of fibers comprise polyester. Additionally, or alternatively, the plurality of fibers comprise a bi-component fiber. In some embodiments, there are a mixture of fiber types. These fiber types can include cotton, rayon, jute, hemp, flax, polyester, bi-component, polypropylene, and any combination. In some embodiments, combinations of bondable fibers with cellulosic fibers are desired. In further embodiments, fibers of various shape can be used such as circular, tri-lobal, triangular, polygonal, flat, oval, lobular, dog bond, square, I beam, and star.
In some embodiments, the fibrous pellet has a dynamic heterogeneous morphology. Additionally, or alternatively, the fibrous pellet has a dynamic heterogeneous porosity and permeability. In some embodiments, the fibrous pellet is configured for time-delayed release of an active ingredient.
In another aspect, a method of manufacturing a fibrous pellet is disclosed. The method comprising: carding a fiber, cross-lapping the fibers to create a layered substrate, bonding the layered substrate, and die-cutting to form pellets. In some embodiments, the method comprises applying an active ingredient to the fiber, the aligned fiber, the layered substrate, the bonded substrate, or the pellets. In some embodiments, bonding the layered substrate comprises needle-punching, hydro-entangling, thermal bonding, ultrasonic bonding, or combinations thereof. In some embodiments, the method further includes applying an active ingredient to the fiber, the aligned fiber, the layered substrate, the bonded substrate, or the pellets.
In another aspect, a fibrous pellet formed by the process of: carding a fiber to generate aligned fibers, cross-lapping the aligned fibers to create a layered substrate, bonding the layered substrate to create bonded substrate, and die-cutting the bonded substrate into pellets is disclosed. In some embodiments, bonding the layered substrate comprises needle-punching, hydro-entangling, thermal bonding, ultrasonic bonding, or combinations thereof. In some embodiments, the process further includes applying an active ingredient to the fiber, the aligned fiber, the layered substrate, the bonded substrate, or the pellets.
Additional features, aspects, and advantages of the invention will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the invention as described herein.
The drawings described herein are for illustrative purposes for selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
The present invention will now be described more fully hereinafter with reference to the accompanying drawings in which exemplary embodiments of the invention are shown. However, the invention may be embodied in many different forms and should not be construed as limited to the representative embodiments set forth herein.
Measurements, amounts, and other numerical data may be expressed or presented herein in a range format. It is to be understood that such a range format is used merely for convenience and brevity and thus should be interpreted flexibly to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within the ranges as if each numerical value and sub-range is explicitly recited. As an illustration, a numerical range of “about 1 to 5” should be interpreted to include not only the explicitly recited values of about 1 to about 5, but also include individual values and sub-ranges within the indicated range. Thus, included in this numerical range are individual values such as 2, 3, and 4 and sub-ranges such as from 1-3, from 2-4, and from 3-5, etc. as well as 1, 2, 3, 4, and 5, individually. The same principle applies to ranges reciting only one numerical value as a minimum or a maximum. Furthermore, such an interpretation should apply regardless of the breadth of the range or the characteristics being described.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
The improved fibrous pellet, referred to herein as “pellet” and “fibrous pellet,” of the present disclosure is a pellet comprised of a plurality of fibers. The pellet may have a tunable shape such as a sphere, disc, cylinder, triangle, star, diamond, etc. The physical and mechanical properties of the pellet are tunable due to the unique method of manufacturing the pellets. Properties such as fiber orientation, compressive and shear properties, density, porosity, and permeability may be tuned to produce a pellet with desirable functionality and properties. The pellets may exhibit the ability change dynamically regarding porosity and permeability during manipulation by the end user. These new properties are possible through the manipulation of fiber orientation and through localized and discrete bonding. The improved fibrous pellets described herein may be used in various applications, including but not limited to buccal, sublingual, and intra-oral substance delivery. Additionally, or alternatively, the fibrous pellets may be used without an applied active ingredient to absorb oral fluids.
The prior art process for manufacturing fibrous pellets is illustrated in
The improved method, disclosed herein, is illustrated in
In some embodiments, the fiber used to form the fibrous pellet, or pellet, is polyester. The polyester fiber may have a denier of between 1 and 40 denier and more preferably between 1.5 and 20 denier. In some embodiments the polyester fiber may be solely composed of 6 denier fiber, while in other embodiments the polyester used will be a combination of multiple denier fibers as to create heterogeneity. The polyester fiber may comprise about 0.1% to about 1.0% finish. The polyester fiber may have approximately 1 to 20 crimps per inch and more preferably 7.5 crimps per inch to 12.5 crimps per inch. Additionally, the polyester fiber may be approximately to 2.5 inches in length. The polyester fiber may be used to make a polyester substrate that is between approximately 100 to 600 grams per square meter with a more preferred range between 200 to 500 grams per square meter. The polyester substrate may be used to make pellets that are approximately 3 to 15 mm in diameter and approximately 3 to 15 mm in height.
The substrate-making procedure 200a begins with opening a bale of fiber at block 210. The fibers are removed from the bale and gently separated into manageable tuft sizes to minimize fiber damage while separating. In some embodiments, the fiber tufts are added to an apparatus configured to blend the fibers 310. In some embodiments, more than one fiber type is added and blended. A range of fibers may be used to achieve the desired mechanical properties and end-product behavior. These fibers can be combinations of traditional fibers with bi-component fibers that contain a core/sheath design such as PE/PET and/or fibers that contain a bonding agent added during fiber manufacture. In some embodiments, the fibers comprise an additive or inclusion that is added to increase resilience, strength, or other properties of the fiber and thus the substrate and pellet formed thereafter.
In some embodiments, a chute feeder feeds the blended fibers into a carding apparatus 330, where the fiber is carded, block 220. Carding, similarly to the prior art process, is the individualization of fibers for untangling and alignment. After carding, the fiber is a low basis weight material predominantly oriented parallel to the Y axis in the XY plane (parallel to the direction of material flow).
After the fibers are separated and aligned, the process continues to block 230, where the fibers will be cross-lapped in a cross-lapping device 340. Cross-lapping includes layering fibers at a ninety-degree angle. This step is where the weight of the substrate is controlled. The more layers of fiber the higher the weight of the substrate. An exemplary device used for cross-lapping is illustrated in
After cross-lapping to form a substrate, the substrate is bonded at block 240. Substrate bonding is performed to bond the fibrous web layers of the substrate together by entangling the fibers perpendicular relative to the plane of the substrate, as illustrated in
In some embodiments, the process includes needle-punching to bond the substrate, using one or more needle-looms 360 as illustrated in
Additionally, or alternatively, hydro-entanglement may be used to bond the substrate. Hydro-entanglement is illustrated in
In other embodiments, thermal bonding is used to bond the substrate; examples of thermal bonding include through-air bonding wherein high temperature air is used to slightly melt the exterior surfaces of fibers enabling bonding of the fibers upon cooling. In some embodiments, the substrate is bonded using high temperature and/or pressure. Additionally, or alternatively, ultrasonic bonding is used to bond the substrate. Similar to through-air bonding, using heated and pressurized bonding rolls, or ultrasonic bonding, creates bonds between fibers through fiber melting and attachment upon cooling. Both processes allow for discrete and targeted bonding of substrates that allow for mechanical property manipulation.
The substrate bonding method may be tailored to provide a final product with desired properties for a specific application. For example, through-air bonding creates a more permanent bond than needle-punching or hydro-entanglement, and can enable the creation of a more resilient structure to resist creep and deformation. The method of substrate bonding may also be dependent on the type of fibers present in the substrate.
In some embodiments, after bonding the substrate the bonded substrate is subjected to slitting and winding at block 250 using a winder apparatus 370. Wound substrate may then be stored for pellet-forming 200b at a later time and/or a different location. The process of pellet-forming 200b, begins by unwinding the bound substrate. The unwound substrate is then subjected to die-cutting, at block 270 to produce pellets. In some embodiments, the process may include direct coupling of pellet die-cutting 270 after substrate bonding, removing the steps of slitting and winding 250 and unwinding the substrate 260.
The macro shape of the structure is achieved through the die-cutting process. Die-cutting may be done by rotary or linear (stamp) die-cutting. In both cases, a die is machined with the desired shapes. The shapes can be spaced separately across/around the die surface or adjacent to one another. In some cases, the shapes can be completely connected as to reduce the amount of unused substrate post cutting. Shapes can all be the same or any number of different shapes. For example, a die can be machined to contain all circular shapes, or a die can be machined to contain circles, squares, and diamonds.
The improved pellet and the prior art pellet are compared in
Fluid movement through the structure can be defined as both fluid being absorbed into a dry structure and/or fluid being desorbed from a structure. In both cases, pressure is the driving force for fluid movement. By having a XYZ oriented design, movement of fluid throughout the structure will occur according to the weighted fiber orientation. For example, a structure with an equal orientation in the XYZ will have an equal distribution of fluid throughout. If the orientation is dominant in the X axis, fluid will have dominant flow in that direction. This occurs for both fluid entering the structure as well as fluid exiting the structure. In a radially oriented design, as seen in the prior art pellet, fluid will tend to follow paths in the radial direction. This has a negative impact both on the rate of fluid movement as well as full utilization of the total structure for fluid management. Fibers aligned in the Z direction enable fluid movement between layers of the XY plane fibers. This fluid behavior is not possible with the prior art pellet as there is no fiber directionality in the axial plane.
The governance of fluid movement in the pellet can be explained by Jurin's Law, Equation 1. Jurin's law is derived from the Young Laplace equation which governs capillary action of fluid, where h is height, γ is surface tension, θ is contact angle, ρ is fluid density, g is gravity, and r is radius of the capillary.
For the improved pellet, described herein, the height can be any distance across the structure, for example, across the X axis, the Y axis, or the Z axis. Surface tension, contact angle, and fluid density can be considered constants, with only the radius changing as fiber orientation changes. Accordingly, as radius decreases, the distance that fluid can travel (h) increases. In some embodiments, the improved pellets may have a distribution of radii which will therefore have a distribution of fluid travel distances. Additionally, the improved pellets, as described herein, may have zones of pore sizes and directionality of pores which enable fluid movement scenarios not possible with the prior art pellet.
The properties, mechanical and fluid dynamic properties, of the fibrous pellet may be tailored through a variety of processing conditions. One such way to tailor the properties is to change the orientation of the fibers in the XY, YZ, and XZ planes. To promote fiber orientation changes, cross-lapping in combination with hydro-entangling and/or needle-punching are utilized. Cross-lapping can be tailored to adjust substrate basis weight, fiber orientation in the X and Y planes. The density of the fibers may also be used to tailor the properties of the pellet.
In some embodiments, the fibrous pellet may be used as a smoke-less and tobacco-free nicotine pouch as described in U.S. patent application Ser. No. 17/178,108, which is hereby incorporated by reference in its entirety.
In some embodiments, the fibrous pellet may be configured to provide a fibrous pellet with time-delayed release of active ingredients. This may be achieved with a pellet with heterogeneous porosity. In some embodiments, a fibrous pellet with heterogeneous porosity may be prepared by incorporating hollow fibers with solid fibers. Additionally, or alternatively, heterogeneous porosity may be achieved by incorporating differently shaped fibers. In other embodiments, the macro-shape of the pellet may provide a pellet with heterogeneous porosity.
In some embodiments, the fibrous pellet may be configured to have a dynamic heterogeneous morphology. A pellet with dynamic heterogeneous morphology may be obtained by tailoring the mechanical properties of the pellet (by altering fiber direction, density, etc as described previously) or by using a fiber with desired properties, such as glass transition temperature. The pellet shape changes due to forces exerted during application or by the tongue, cheek and gum when in the mouth of a user. A pellet with a dynamic heterogeneous morphology enables a fitted pellet for comfort and/or proper positioning of the pellet.
In some embodiments, the fibrous pellet may be configured to have dynamic heterogeneous porosity and permeability. A pellet with dynamic heterogeneous porosity and permeability may be obtained by tailoring the mechanical properties of the pellet, as previously described. Along with pellet shape change, pellet compression and shear change occurs with pellet adjustment in the oral cavity. This creates a shift in the pore size distribution that is unique to each pellet depending upon the pellet's orientation relative to the forces applied, giving a discontinuous porosity and permeability profile which enables varying active release behavior during use.
In some embodiments, the pellet comprises an active ingredient. Active ingredients include, but are not limited to, nicotine, nitroglycerin, cannabinoid and cannabinoid derivatives, and any other active ingredient capable of absorption by the oral mucosa. In some embodiments, the active ingredient may be applied and absorbed into the pellet after pellet-forming. In some embodiments, the active ingredient is applied and absorbed into the substrate after cross-lapping. Additionally, or alternatively, the active ingredient may be applied and absorbed into the substrate after bonding. In some embodiments, the active ingredient is applied to the fiber after carding. Additionally, or alternatively, the active ingredient is applied to the fiber prior to carding. The active ingredient may be applied in a solution, or carrier liquid, with other additives such as flavorings.
To test the recovery of the pellet after compression, the compression test illustrated in
The fluid retention of the pellet was measured using two different tests: the squeeze out test and the free fluid lost test. The squeeze out test measures the amount of fluid lost by squeezing, or compressing, the pellet. The pellet is put on top of filter paper and squeezed, and the filter paper is measured for the change in weight. The free fluid lost test measures the amount of fluid lost after the pellet sits on a piece of filter paper for one minute by using the same process of weighing the filter paper before and after the test.
The fluid lost measured during a squeeze out test is shown in
The foregoing description provides embodiments by way of example only. It is envisioned that other embodiments may perform similar functions and/or achieve similar results. Any and all such equivalent embodiments and examples are within the scope of the present invention.
| Number | Date | Country | |
|---|---|---|---|
| 63352680 | Jun 2022 | US |
