Material forming method and formed article

Abstract

The present invention relates to a method for forming a material having a plurality of gaps (such as a network of pores) and to a formed article formed by this method. In a preferred embodiment, the material is a foam, such as a polyurethane foam. The forming method enables such a material to be formed using a contour forming machining method including computer numerical control (CNC) milling, provided only as an example. In contrast to a method for producing a formed material (e.g. by polymerization of a monomer solution or emulsion), in various aspects, the present invention considers the forming of an existing (pre-formed) material having a plurality of gaps, such as a network of pores.

Description

Technology Field

[0001] The present invention relates to a method for shaping a material having multiple interstices (such as a network of voids) and shaped products formed by this method. In preferred embodiments, the material is a polyurethane foam and a foam. The shaping method enables such a material to be shaped using contour-shaping machining methods, including computer numerical control (CNC) milling, provided only as an example. In contrast to methods for producing shaped materials (e.g., by polymerization of a solution or emulsion of monomers), in various embodiments, the present invention is intended to shape an existing (pre-formed) material having multiple interstices, such as a network of voids. Background Technology

[0002] The production of flexible foam is a means of shaping a foam for a desired final product by shaping foam stock or casting a resin system (excluding casting for mass-produced foam stock intended for production). Shaping methods include: hand shaping; computer numerical control shaping (e.g., CNC mill, lathe, turn-mill, and multi-axis mechanical arm forming).

[0003] Materials such as polyurethane foam are notoriously difficult to mold precisely. While it is relatively easy to cut such foams using blades, saws, etc., attempting to shape the contours of such foams using conventional machining methods (e.g., Computer Numerical Control (CNC) methods) results in inaccurate contours and typically undesirable machining finishes. In particular, the inventors are convinced that deformation of the foam by machining tools during the molding process causes poor finishes, which consequently leads to the material being cut or even ruptured at inaccurate locations. Such machining does not produce a smooth surface, but rather a rough surface.

[0004] Despite these challenges, molded polyurethane foams are widely used for padding in seats, packaging, and the like. Users often require precision-molded polyurethane products for applications such as wheelchair seats, which necessitate bespoke shaped products.

[0005] There have been few attempts to overcome the problems described here. Roughly speaking, previously used methods can be classified as follows:

[0006] ㆍ Cryogenic processes. This machining method is relatively fast, accurate, and achieves the desired results, but in return, it entails high equipment costs (which must withstand extreme temperatures), the handling, storage, and excessive use of liquefied gas coolants, and exposure to the dangers of fine foam dust and liquefied gas;

[0007] • Liquid freezing. This method involves the step of saturating the foam with water in situ prior to freezing. Freezing is a simplified version of the cryogenic process that enables low costs comparable to cryogenic and dry machining by allowing the use of frozen water to maintain a sufficiently low temperature. However, for optimal results, this process requires that the water remain frozen throughout all stages of the forming process (which can be aided by the cooling of the foam and water). As the water expands while solidifying, the foam is finely fragmented. Furthermore, freezing of water actually leads to suboptimal machining quality and precision because machining tolerances can be unpredictably disturbed by the expansion of water within the foam due to reduced temperatures, and combined with the loss of melting ice around the forming surface when high-speed / friction machining tools come into contact with the surface. Another problem with this method is that it requires the inclusion of water, and accordingly, the machine parts must be water-compatible to prevent corrosion, electrical failure, and leakage; and

[0008] ㆍ Dry machining. This method refers to techniques other than the cryogenic and liquid freezing described above, requires extended machining times, advanced equipment and tools, exposes technicians to hazardous dust, and provides only limited geometric shapes.

[0009] Due to the limitations of these methods, particularly the health risks associated with the generation of fine particles, conventional manual molding methods are widely used in the production of foams.

[0010] In addition to molding flexible foams, it is often desirable to mold porous metal materials that are typically inflexible. Such materials suffer from different problems compared to flexible foams. For example, machining porous metal materials produces burrs that change in size and shape, depending in part on the temperature and material used. At high temperatures, the contact point between the cutting tool and the metal softens, causing the metal to plastically displace and tend to form smears or burrs. Such temperatures also accelerate the dulling of the machining tool. To overcome these problems, a coolant can be applied to lower the temperature of the material, hardening the metal to produce a cleaner cut and prevent burrs, smears, and associated damage. As has become clear from further teachings in the field of porous metal machining, such problems are the result of ductile shear, and the solution to staining relies primarily on achieving "brittle shear" using cryogenic methods.

[0011] As with all machining methods, and in the methods mentioned above, it is necessary to ensure that the material to be formed is firmly secured during the forming process. Traditionally, the material is clamped or otherwise secured, for example, by the use of adhesives (e.g., cyanoacrylates or similar "super-glue" adhesives). Such techniques typically damage the material due to the direct mechanical action of the clamp or as a result of the excessive force required to break the bond with the adhesive.

[0012] The object of the present invention is to solve one or more of the aforementioned problems, or at least to provide a useful option to a person skilled in the art.

[0013] In a first embodiment, the present invention provides a method for shaping an elastic or viscoelastic material having a plurality of interstices, wherein the method comprises:

[0014] i. A step of providing an elastic or viscoelastic material having a plurality of gaps;

[0015] ii. A step of bringing the material into contact with an additive so that at least a portion of the additive is incorporated into at least a portion of a plurality of gaps of the material;

[0016] iii. A step of applying conditions to the material such that at least a portion of the incorporated additive solidifies, hardens, and / or stiffens;

[0017] iv. A step of molding the material incorporating the additive, which has been solidified, hardened, and / or rigidified, to form a molded material incorporating the additive; and

[0018] v. A step of removing at least one portion of the incorporated additive from the molded material in which the above additive is incorporated; comprising,

[0019] The additive solidifies, hardens, and / or hardens at temperatures above 0°C.

[0020] In some embodiments, the elastic or viscoelastic material having a plurality of voids is an elastic or viscoelastic material having a network of voids.

[0021] Accordingly, in a second aspect, the present invention provides a method for forming an elastic or viscoelastic material having a network of pores, and the method comprises:

[0022] i. A step of providing an elastic or viscoelastic material having a network of pores;

[0023] ii. A step of bringing the material into contact with an additive so that at least a portion of the additive is incorporated into at least a portion of the network of pores of the material;

[0024] iii. A step of applying conditions to the material such that at least a portion of the incorporated additive solidifies, hardens, and / or stiffens;

[0025] iv. A step of molding a material incorporating a solid, hard, and / or stiff additive to form a molded material incorporating the additive; and

[0026] v. A step of removing at least a portion of the incorporated additive from the molded material in which the additive is incorporated; comprising,

[0027] The additive solidifies, hardens, and / or hardens at temperatures above 0°C.

[0028] The method of the present invention enables the production of a molded elastic or viscoelastic material having a desired surface finish. The method uses an additive that solidifies, hardens, and / or stiffens at a temperature above the freezing point of water (0 °C, 101.325 kPa at standard atmospheric pressure). The additive is incorporated into the material, and accordingly, the material can be molded while the additive is solidifying, hardening, and / or stiffening, in such a way that undesirable deformation of the material is prevented as the material is molded.

[0029] As merely an example, in some embodiments, the additive is a wax, and the elastic or viscoelastic material having a plurality of voids (e.g., a network of voids) is a polyurethane foam. In such embodiments, the method may include the step of incorporating molten wax into a material that solidifies upon cooling to room temperature, and then the foam may be formed by CNC milling. Then at least a portion of the wax is removed from the formed foam.

[0030] Unbound by theory, as is estimated, these methods allow the material to be formed without substantially altering the elastic modulus of the material itself. Furthermore, the additive can be selected such that the temperature difference between the liquid and solid additives is limited, thereby severely limiting any shrinkage of the material. Additionally, by carefully controlling the amount of additive incorporated into the material, it is possible to better control potential expansion or shrinkage by preventing material saturation.

[0031] Additionally, as is estimated, previously disclosed cryogenic approaches weaken and damage the structure of foam materials at the molecular level to achieve machining, whereas the present invention adds a mechanical advantage to the advantages of a machining tool by concentrating shear force between a rotating cutting edge of a tool with high momentum and a fixation additive (particularly wax) with high inertia.

[0032] As such, the present invention represents a significant advancement over previously disclosed methods because it allows the molding of elastic or viscoelastic materials at room temperature and other temperature ranges above the freezing point of water. The advantage of the present invention is formed by the self-healing properties of the additives used in some embodiments, for example, any additive (e.g., wax) that is temporarily melted by a machining tool subsequently hardens after the tool has moved, thereby contributing once again to the stiffness of the material. The use of wax-based additives can also lubricate the machine and cutting tool to extend their lifespan, and can also lubricate in this way while reducing the risk of electrical failure that would otherwise be possible when water is used in previously disclosed liquid freezing methods.

[0033] In a third embodiment, the present invention provides a molded elastic or viscoelastic material having a plurality of gaps (e.g., a network of gaps) produced by the method of the first or second embodiment.

[0034] In a fourth embodiment, the present invention provides the use of a solid, hard and / or rigid additive at a temperature above 0°C for forming an elastic or viscoelastic material having a plurality of gaps (e.g., a network of gaps) incorporating the additive.

[0035] In a fifth embodiment, the present invention provides a contoured elastic or viscoelastic material having a plurality of gaps (e.g., a network of gaps), at least one part of the material has an additive incorporated into the material, and the additive is a solid, hard and / or rigid additive at temperatures above 0°C.

[0036] The term “contoured” as used in this specification refers to the form of an article to which the techniques of contouring, contour machining, 3D machining, or 3D contour machining are applied.

[0037] In a sixth aspect, the present invention provides a method for forming an elastic or viscoelastic material having a plurality of gaps, and the method comprises:

[0038] i. A step of providing an elastic or viscoelastic material having a plurality of gaps;

[0039] ii. A step of bringing the material into contact with an additive so that at least a portion of the additive is incorporated into at least a portion of a plurality of gaps of the material;

[0040] iii. A step of applying conditions to the material such that at least a portion of the incorporated additive solidifies, hardens, and / or stiffens;

[0041] iv. A step of molding a material incorporating a solid, hard, and / or rigid additive to form a molded material incorporating the additive; and

[0042] v. A step of removing at least a portion of the incorporated additive from the molded material in which the additive is incorporated; comprising,

[0043] The additive is not water, and the additive solidifies, hardens, and / or hardens when a change in conditions selected from heat, magnetism, electricity, chemistry, and / or electromagnetics is applied.

[0044] In a seventh aspect, the present invention provides a method for forming an elastic or viscoelastic material having a network of pores, wherein the method comprises:

[0045] i. A step of providing an elastic or viscoelastic material having a network of pores;

[0046] ii. A step of bringing the material into contact with an additive so that at least a portion of the additive is incorporated into at least a portion of the network of pores of the material;

[0047] iii. A step of applying conditions to the material such that at least a portion of the incorporated additive solidifies, hardens, and / or stiffens;

[0048] iv. A step of molding a material incorporating a solid, hard, and / or rigid additive to form a molded material incorporating the additive; and

[0049] v. A step of removing at least a portion of the incorporated additive from the molded material in which the additive is incorporated; comprising,

[0050] The additive is not water, and the additive solidifies, hardens, and / or hardens when a change in conditions selected from heat, magnetism, electricity, chemistry, and / or electromagnetics is applied.

[0051] In some embodiments, the elastic or viscoelastic material having a plurality of gaps is an elastic or viscoelastic material having a network of gaps.

[0052] In an eighth aspect, the present invention provides a method for forming an elastic or viscoelastic material having a network of voids, wherein the method comprises:

[0053] i. A step of providing an elastic or viscoelastic material having a network of pores;

[0054] ii. A step of bringing the material into contact with an additive so that at least a portion of the additive is incorporated into at least a portion of the network of pores of the material;

[0055] iii. A step of applying conditions to the material such that at least a portion of the incorporated additive solidifies, hardens, and / or stiffens;

[0056] iv. A step of molding a material incorporating a solid, hard, and / or rigid additive to form a molded material incorporating the additive; and

[0057] v. A step of removing at least a portion of the incorporated additive from the molded material in which the additive is incorporated; comprising,

[0058] The additive solidifies, hardens, and / or hardens when a change in selected conditions from heat, magnetism, electricity, chemistry, and / or electromagnetics is applied.

[0059] In a ninth embodiment, the present invention provides a molded elastic or viscoelastic material having a plurality of gaps (e.g., a network of gaps) produced by the method of the fifth embodiment or the method of the sixth embodiment.

[0060] In a tenth embodiment, the present invention provides for the use of an additive to form an elastic or viscoelastic material having a plurality of gaps (e.g., a network of gaps) into which the additive is incorporated, wherein the additive solidifies, hardens, and / or stiffens when a change in conditions selected from magnetic, electrical, chemical, and / or electromagnetic is applied.

[0061] In the eleventh embodiment, the present invention provides a contoured elastic or viscoelastic material having a plurality of gaps (e.g., a network of gaps), at least a portion of the material has an additive incorporated into the material, the additive solidifies, hardens, and / or stiffens when a change in conditions selected from magnetic, electrical, chemical, and / or electromagnetic is applied.

[0062] In a 12th embodiment, the present invention provides a method for forming a molded elastic or viscoelastic material having a plurality of gaps, and the method comprises:

[0063] i. A step of contacting an additive with a resin that can be cured to form an elastic or viscoelastic material in a container to form a mixture;

[0064] ii. A step of degassing the mixture, for example, by vacuum, and / or mixing the mixture to form a homogeneous blend;

[0065] iii. A step of curing the resin to form an elastic or viscoelastic material in which at least a portion of the additive is incorporated;

[0066] iv. A step of molding a material mixed with an additive to form a molded material mixed with an additive; and

[0067] v. optionally, a step of removing at least a portion of the incorporated additive from the molded material in which the additive is incorporated; comprising,

[0068] The additive is not water, and the additive solidifies, hardens, and / or hardens when a change in conditions selected from heat, magnetism, electricity, chemistry, and / or electromagnetics is applied.

[0069] In a 13th embodiment, the present invention provides a method for forming a molded elastic or viscoelastic material having a network of pores, and the method comprises:

[0070] i. A step of contacting an additive with a resin that can be cured to form an elastic or viscoelastic material in a container to form a mixture;

[0071] ii. A step of degassing the mixture, for example, by vacuum, and / or mixing the mixture to form a homogeneous blend;

[0072] iii. A step of curing the resin to form an elastic or viscoelastic material in which at least a portion of the additive is incorporated;

[0073] iv. A step of molding a material mixed with an additive to form a molded material mixed with an additive; and

[0074] v. optionally, a step of removing at least a portion of the incorporated additive from the molded material in which the additive is incorporated; comprising,

[0075] The additive is not water, and the additive solidifies, hardens, and / or hardens when a change in conditions selected from heat, magnetism, electricity, chemistry, and / or electromagnetics is applied.

[0076] Additional aspects of the invention that should be considered in all novel aspects of the invention will become apparent to a person skilled in the art by reading the following description, which provides at least one example of the actual application of the invention. Brief explanation of the drawing

[0077] One or more embodiments of the present invention will be described below merely as examples, with reference to the following drawings, without intent to limit, where: Figure 1 shows a schematic flowchart of a process for incorporating a wax additive into a foam material and fixing the material to a processing surface. Figure 2 shows a schematic flowchart of the process for processing a single-sided or double-sided foam material mixed with wax. Figure 3 shows a schematic flowchart of a process for removing at least a portion of a wax additive incorporated from a foam material. FIG. 4 shows a schematic flowchart of the methods of the present invention applied to a number of molded raw materials. FIG. 5 shows a schematic flowchart of the method of the present invention for producing a molded article using a solid additive. FIG. 6 shows a schematic flowchart of a number of embodiments of the method of the present invention, including the step of contacting a foam with an additive. Figure 7 shows a schematic flowchart of the use of a container as a mold. FIG. 8 shows a schematic flowchart of a process using solid granules, powders, and other additives. Optionally, these can be manipulated by an external stimulus (which may be solid or otherwise). Figure 9 shows a schematic flowchart of a process in which the addition or removal of heat can be used to change the properties of the additives. Figure 10 shows a schematic flowchart of a continuous process for the process illustrated in Figure 9. Figure 11 shows a schematic flowchart of the additive removal process. Figures 12 and 13 show a schematic flowchart of a process using a mold to create an impression within the foam before CNC machining. The drawings do not necessarily indicate any association or sequence of operations between the steps on the page. Foam is used as an example for exemplary purposes only. The vacuum bag is for illustrative purposes only. The vacuum bag may be arranged in other suitable arrangements, such as sealing a suitable sheet onto a solid plate, or may be arranged as a flexible gusset attached between two solid plates so that the sheets can be gathered together under vacuum. The plates may have one or more inlets / outlets in the form of separate openings or valves; or in the form of multiple openings or valves that can be converged by a manifold. The press may be mechanical or manual; or operated by hand; or a combination of bag arrangements as described above that are compressed mechanically or by hand. Specific details for implementing the invention

[0078] The term "elastic or viscoelastic" materials as used in this specification refers to:

[0079] i. Deformation elasticity (elasticity); or

[0080] ii. Refers to a class of materials that are substantially deformable and elastic so that some energy is dissipated through a process of deforming from a first position to a second position and substantially returning to the first position (viscoelastic).

[0081] The material of the present invention comprises a matrix of a solid material having a plurality of interstitial spaces within it, such as a network of pores. Examples of interstitial spaces include: cells having incomplete wall regions; tunnels; channels; holes; void platelets; interstitial spaces; etc. The interstitial spaces are fluidly connected so that an additive can penetrate into the material, for example, through the network of pores. The interstitial spaces may be arranged in an array of interstitial spaces such as in a honeycomb material. Such interstitial spaces may or may not be fluidly connected to one or more other interstitial spaces. Nevertheless, these interstitial spaces may allow the additive to be added to the interstitial spaces and / or removed from the interstitial spaces. Preferably, these interstitial spaces will allow the additive to be added to the interstitial spaces and removed from the interstitial spaces.

[0082] Therefore, the materials of the present invention must be distinguished from the following materials:

[0083] Materials to which additives cannot be added and / or

[0084] Materials from which additives cannot be removed and / or

[0085] A material that does not contain a network of fluid-communicating pores and typically contains a significant number of distinct gas cells.

[0086] Just as an example, an open-cell foam is an elastic or viscoelastic material having a network of pores and can be used in the methods of the present invention, whereas a closed-cell foam is not an elastic or viscoelastic material having a network of pores that can be used in the methods of the present invention.

[0087] As used herein, “gaps” refers to spaces within a material that may be filled with, for example, a gas, liquid, or some other material other than an elastic or viscoelastic material. Gaps are typically small spaces, but nevertheless, they may be filled with, for example, a gas, liquid, or some other material other than an elastic or viscoelastic material. Gaps may be of a regular shape or an irregular shape. Gaps may be of the same size or different sizes. For example, in foams, gaps typically consist of spaces of varying sizes. The size of any given gap may be measured in various ways, including minimum, maximum, or average linear dimensions. It may be convenient to measure the size of the gap(s) as an average linear dimension across two or more axes, such as two orthogonal axes. The minimum limit of the size will typically be limited only by the ability of the gas, liquid, or some other material other than the elastic or viscoelastic material to penetrate at least part of the gap(s). While the maximum size limit will typically be unlimited, gaps having average linear dimensions of up to about 1000 mm, e.g., up to about 500 mm, e.g., up to about 300 mm, e.g., up to about 100 mm, e.g., up to about 50 mm, e.g., up to about 25 mm, e.g., up to about 10 mm, e.g., up to about 5 mm, e.g., up to about 2 mm, e.g., up to about 1 mm will be preferred. In some embodiments, the gaps will have a size of at least about 0.001 mm, e.g., at least 0.01 mm, e.g., at least 0.1 mm. As can be understood, a number of techniques can be used to form materials having multiple gaps, such as the emulsion polymerization of polyurethane. These techniques will typically produce materials having gaps with a size distribution.As such, in some embodiments, the dimensional limitations described herein will apply to at least 60% of the gaps, e.g., at least 70% of the gaps, e.g., at least 80% of the gaps, e.g., at least 90% of the gaps, e.g., at least 95% of the gaps. In some embodiments, the dimensional limitations described herein will apply to 100% of the gaps.

[0088] As used in this specification, plural means two or more. Typically, an elastic or viscoelastic material may have at least a number (3) of gaps, such as a plurality of gaps as well as a plurality of gaps. An elastic or viscoelastic material may have at least 5, for example, at least 10, for example, at least 20, for example, at least 50, for example, at least 100, for example, at least 500, for example, at least 1000 gaps.

[0089] As used herein, "void" refers to a space within a material that may be filled with, for example, a gas, liquid, or some other material other than an elastic or viscoelastic material. The voids are typically small spaces, but nevertheless, they may be filled with, for example, a gas, liquid, or other material other than an elastic or viscoelastic material. The voids may be regular or irregular in shape. The voids may be of the same or different sizes. For example, in a foam, the voids typically consist of spaces of varying sizes. The size of any given void can be measured in various ways, including minimum, maximum, or average linear dimensions. It may be convenient to measure the size of the void(s) as an average linear dimension across two or more axes, such as two orthogonal axes. The minimum limit of the size will typically be limited only by the ability of the gas, liquid, or some other material other than the elastic or viscoelastic material to penetrate at least part of the void(s). While the maximum size limit will typically be unlimited, pores having average linear dimensions of up to about 1000 mm, e.g., up to about 500 mm, e.g., up to about 300 mm, e.g., up to about 100 mm, e.g., up to about 50 mm, e.g., up to about 25 mm, e.g., up to about 10 mm, e.g., up to about 5 mm, e.g., up to about 2 mm, e.g., up to about 1 mm will be preferred. In some embodiments, the pores will have a size of at least about 0.001 mm, e.g., at least 0.01 mm, e.g., at least 0.1 mm. As can be understood, a number of techniques can be used to form materials having a network of pores, such as the emulsion polymerization of polyurethane. These techniques will typically produce materials having pores with a size distribution.As such, in some embodiments, the dimensional limitations described herein will apply to at least 60% of the voids, e.g., at least 70% of the voids, e.g., at least 80% of the voids, e.g., at least 90% of the voids, e.g., at least 95% of the voids. In some embodiments, the dimensional limitations described herein will apply to 100% of the voids.

[0090] As can be understood, not all pores within the material of the present invention necessarily need to be in fluid communication with one another. It is sufficient for the present invention if a significant number (e.g., at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%) are in fluid communication with one another. As such, the term “network of pores” as used herein refers to a significant number (e.g., at least 10%) of pores that are in fluid communication with one another. Typically, at least 50% of the pores (e.g., at least 60%, at least 70%, at least 80%, at least 90%) are in fluid communication with one another.

[0091] Although each gap is not necessarily an interconnected cell, one example of a material having multiple gaps that is functionally identical in a different way to the more extensively networked gap-filled materials described above is a flexible elongated honeycomb material having open cells in which additives are not easily (or at all) transferred from cell to cell. This is a conventional material and can be used as a substitute for general soft polyurethane foams. Another example is gill-like or similar to a soft, flexible heatsink, comprising a number of long members (e.g., plates, wings, or rods). In this example, the material may have gaps (between the long members), but there is no substantial interconnection between the gaps.

[0092] Other such materials of the present invention having multiple gaps may be described as having a brush-like appearance in which the material has parallel or linear filaments (and can be fixed at one or both ends). For example, a material having the appearance of a dense silicone brush may be molded using the disclosed invention. The purpose of this may be for the prototype or small-batch production of contoured brushes or various vibration damping and cushioning systems.

[0093] As can be understood, the present invention is based, in part, on the ability of an additive to penetrate into a material through gaps such as voids. Thus, the dimensions and other properties (including chemical and / or physical properties of the surrounding matrix of the material) of the gaps (such as voids) are limited only by the requirement that the additive can penetrate into the material through the gaps such as voids to a sufficient extent for the method of the present invention to be carried out.

[0094] Materials having multiple pores (e.g., a network of pores) can be formed in various ways, including in some embodiments incorporating an expanding agent, such as sodium carbonate, into the material so that the agent releases gas when certain conditions, such as heating, are applied to the material. Examples of such materials having multiple pores (e.g., a network of pores) include foams, felts, lattices, scaffolds, coiled materials, meshes, and webs. Preferably, the material of the present invention is a foam, and as can be understood, the conventional principles described herein may apply to all elastic or viscoelastic materials having multiple pores (e.g., a network of pores), but it is convenient to describe the invention with respect to foams (for illustrative purposes only). Foams may be formed from natural or synthetic polymers, at least partially, but not entirely.

[0095] As can be understood, there are many known materials having multiple voids (e.g., a network of voids) that are neither elastic nor viscoelastic. These materials include: metal foams; rigid foams (e.g., expanded polystyrene (EPS) and extruded polystyrene (XPS)); and rigid grade foams (e.g., rigid polyurethane (PU), rigid melamine foam). These materials are not considered by the present invention for the reasons discussed below, including the fact that the elastic or viscoelastic properties of the material can be advantageously utilized to incorporate additives. Without these properties, the incorporation and subsequent removal of additives are more difficult to achieve.

[0096] As can be understood, the material should preferably be selected to be substantially resistant to the physical and / or chemical conditions applied in the method of the present invention.

[0097] As used herein, the term “additive” refers to a component that is distinguished from elastic or viscoelastic materials and can be incorporated into at least a portion of a plurality of voids (e.g., a network of voids) of the material. Examples of additives are as follows:

[0098] ㆍ Waxes or wax-like compounds and mixtures thereof. The wax may preferably be water-insoluble. The wax-like compounds may be water-soluble, such as PEG, panthenol, wax-like emulsifiers, and mixtures thereof;

[0099] ㆍ Crystalline solids / supersaturated liquids (e.g., supersaturated solutions stable at room temperature (e.g., sodium acetate trihydrate or similar); supersaturated solutions that are not stable at room temperature but require less heat than pure molten sucrose to remain liquid, e.g., molten crystalline materials that crystallize upon cooling (e.g., sucrose) (this example may also include one or more modifiers to lower the melting point)). Salts and sugar alcohols may be used. Eutectic compounds of sugar alcohols and other mixtures may also be useful;

[0100] ㆍ Liquid crystallizing compounds (e.g., electroactive liquids that self-assemble to form a harder material and provide some resistance (e.g., electroactive materials consisting of a solution containing an amphiphilic mesogen, which can gel or harden in response to electrical stimulation and may be reversible even if not water-soluble for removal));

[0101] ㆍ Non-Newtonian compounds that solidify, including those that solidify upon machining (e.g., corn starch and water that harden in response to applied cutting forces—these examples may also benefit from applied acoustic vibrations; corn starch and oil as electrorheological liquids that harden upon the application of electrical stimulation). Advantages of the control of airborne particles and the apparent self-healing properties of some such materials that can flow into previously cut gaps (e.g., voids);

[0102] ㆍ Granules / powders / other solids (e.g., iron powder or granules (e.g., iron powder) that can form a quasi-solid when flowed into some materials having multiple voids (e.g., a network of voids) and then a magnetic stimulus (where friction between the granules and the foam will essentially hold them in place) is applied. Such powders / granules can be removed via gravity and / or sonic stirring, optionally in combination with magnetic force and / or a liquid to enhance it). Typically, the advantage of using magnets for powders or granules is that the powder or granules can be easily separated from the waste;

[0103] • Granules / powders / other solids capable of flowing into some materials having multiple voids (e.g., a network of voids) without any magnetic influence or other changes in conditions. For example, before a molded foam is stirred (e.g., after removal from a container) to remove the powder additive, the foam may be fixed within a container having walls (wherein the additive powder is stirred into the multiple voids (e.g., a network of voids) of the foam as well as into any space between the foam and the container walls; thus, the foam containing the powder additive is placed in a filled and supported state so that the foam and the additive can be molded). The nominal advantages of using granules / powders / other solids capable of flowing into some materials having multiple voids (e.g., a network of voids) are as follows: a reduction in energy requirements is possible because significant heating is not required, as the powder can be vibrated in and out or melted if necessary; faster processing times because the additive does not require cooling; and because there is no thermal expansion, there is little to no change in the size of the filled foam and the empty foam;

[0104] • Granules / powders / other solids capable of undergoing a change of state, such as being meltable. In such examples, granules / powders / other solids may flow into some material having multiple voids (a network of voids). For example, a foam may be fixed in a container with walls; additive powder is stirred into multiple voids (e.g., a network of voids) of the foam as well as into any space between the foam and the container walls; thus, the foam containing the powder additive is placed in a filled and supported state so that the foam and the additive can be molded; and if heat is applied to the filled and supported foam to remove the powder additive before stirring the molded foam (e.g., after removing it from the container), the granules / powders / other solids will be allowed to melt the granules / powders / other solids and the foam composite on the outer surface of the composite material, creating a partial or complete seal. Likewise, the bottom surface may be melted to adhere to a working surface, for example. The nominal advantages of using granules / powders / other solids that can flow into some materials having multiple voids (e.g., a network of voids) are as follows: reduced energy requirements are possible because significant heating is not required since the powder can vibrate in and out or melt if necessary; faster processing times because the additive does not require cooling; and little to no change in the size of filled and empty foams because there is no thermal expansion;

[0105] Liquids that can be hardened or arranged and oriented to have greater rigidity by other means (e.g., magnetic fluids, liquids that harden in response to stimulation and return to liquid without stimulation; starch solutions dried or hardened using heat; proteins such as gelatin / collagen existing in solution form that subsequently undergo intermolecular gelation).

[0106] Preferably, the additive will be a wax or a wax-like compound.

[0107] As used herein, the expression “wax or wax-like compound” means a compound that is sufficiently solid, hard, and / or rigid at temperatures above the freezing point of water (0 °C at standard atmospheric pressure, 101.325 kPa), but melts or softens without decomposing at temperatures above about 60 °C (e.g., above about 50 °C, above about 40 °C), in order to facilitate the performance of the method of the present invention that enables the production of a desired molded material. More typically, “wax or wax-like compound” is typically solid, hard, and / or rigid at temperatures above 15 °C (e.g., above 20 °C), but melts without decomposing at temperatures above about 60 °C (or above about 50 °C, or above about 40 °C) or softening It refers to compounds that become. For instance, these waxes or wax-like compounds are oily additives that flow above 25°C, become nearly gel-like just below 25°C, and can be considered machinable at any temperature (even if low quality), but cooling below 0°C will improve processing results. An example of such oily additives is partially hydrogenated oil, which is a paste or gel-like at 25°C but becomes fluid above 25°C and can permeate the foam. These additives remain stable in the foam at 25°C and can provide increasingly processable results as the temperature decreases. Below 0°C, they can be as rigid as paraffin wax at 25°C. In contrast to water, these oily additives will be sufficiently confined within the pores of the foam at temperatures above the freezing point of the additive, including processing temperatures of 25°C.

[0108] Wax is typically an organic substance (typically an aliphatic hydrocarbon) and is insoluble in water at room temperature. Wax can be wetted in water and can form creams, gels, and / or pastes in some solvents, such as non-polar organic solvents. Wax can dissolve in some non-polar organic solvents, typically when heated. Wax can spontaneously emulsify in the presence of some liquid to form a microemulsion, and / or form an emulsion with some liquids in the presence of surfactant(s).

[0109] Wax may have a melting point in the range of about 40°C to about 150°C. In this sense, melting may also occur sufficiently at less than 40°C to facilitate incorporation within a number of gaps (e.g., a network of pores) of the material. As can be understood, incorporation may be achieved, for example, while only a portion of the wax is substantially liquid and the remainder is microcrystalline.

[0110] Wax can also be defined by its viscosity. Viscosity measures the internal resistance of a material to flow, where materials with higher viscosity are considered "thicker" and less fluid than materials with lower viscosity. The melt viscosity of wax can vary from low to high and typically depends on the wax's molecular weight, crystallinity, and whether the wax is oxidized or copolymerized. As the molecular weight and density of the wax increase, the melt viscosity increases, while as the crystallinity of the wax increases, the melt viscosity decreases. The fracture properties of the wax—that is, its affinity for particle size reduction by mechanical force—increase with higher crystallinity and decrease as the density and molecular weight of the wax increase. Above the melting point, the melt viscosity of the wax is typically low.

[0111] Suitable waxes include both natural and synthetic waxes. Suitable waxes may include the following:

[0112] ㆍ Animal waxes (e.g., beeswax, Chinese wax, shellac wax, spermaceti, and wool wax (lanolin));

[0113] ㆍ Vegetable waxes and hardened vegetable oils (e.g., bayberry wax, carnauba wax, castor wax, esparto wax, Japanese wax, jojoba oil wax, ouricury wax, rice bran wax, soy wax, and hardened vegetable waxes - especially if they are paste / grease at room temperature);

[0114] ㆍ Mineral waxes (e.g., ceresin waxes, montan wax, ozocerite wax, and peat wax);

[0115] ㆍ Petroleum waxes (e.g., paraffin wax and microcrystalline wax); and

[0116] ㆍ Synthetic waxes (e.g., polyolefin waxes including polyethylene and polypropylene waxes, wax-grade polytetrafluoroethylene wax (PTFE wax-like grade), Fischer-Tropsch wax, stearamide waxes (including ethylene bis-stearamide wax), polymerized α-olefin waxes, substituted amide waxes (e.g., esterified or saponified substituted amide waxes), polyethers (e.g., polyethylene glycol, e.g., PEG2000), and other chemically modified waxes (e.g., PTFE-modified polyethylene wax))

[0117] In addition to the combinations mentioned above. Among these, preferred waxes include hydrogenated vegetable waxes (e.g., palm wax and soy wax) and polyethers (e.g., polyethylene glycol). Solid fractions of hydrogenated vegetable oils and lanolin are particularly preferred due to the environmental and sustainable benefits they provide to the method and product of the present invention. Furthermore, paraffin, microcrystalline, and various synthetic waxes are preferred.

[0118] In addition, as can be understood, many other additives such as sugars, sugar alcohols, salts, and iron powder are also desirable from an environmental / sustainability / resource recycling perspective.

[0119] Other examples of additives include dry ferrous powder or compositions containing iron particles (e.g., colloids), the properties of which can be controlled by magnetic stimulation to orient the foam in a manner that hardens it once incorporated. Additional examples of additives include: non-Newtonian materials that harden in response to stimulation such as high-frequency mechanical waves; or liquid crystals that align to a hardened state upon electrical stimulation. These examples allow for the control of additive properties and can increase the ease of additive removal.

[0120] Specific examples of additives tested in the processes described herein include the following, which are listed along with their perceived benefits:

[0121] ㆍ PEG1000-3000 - Hardness, processability, reduction of suspended particles, melting point, water solubility

[0122] ㆍ PEG3000-20000 - Hardness, processability, reduction of suspended particles, melting point, water solubility

[0123] ㆍ Paraffin wax - Hardness, processability, reduction of suspended particles, melting point

[0124] ㆍ Additives possessing additional qualities related to sustainability, renewableity, and environmental impact include the following:

[0125] - Xylitol, erythritol, sorbitol; erythritol / xylitol, erythritol / sorbitol, sorbitol / xylitol of eutectic - Hardness, melting point, processability, water solubility

[0126] - Behentrimonium Methosulphate 25, Glyceryl Monostearate, Stearic Acid - Hardness, Melting Point, Processability, Reduction of Suspended Particles

[0127] - Sodium acetate trihydrate - Hardness, melting point, processability, water solubility

[0128] - Soybean, palm, castor wax, and mixtures - Hardness, melting point, machinability, reduction of suspended particles

[0129] - Isosorbide and 1,6-hexanediol - Hardness, melting point, processability, reduction of suspended particles

[0130] - Starch / water mixtures - water solubility, machinability, reduction of suspended particles

[0131] - Iron powder - Hardness, machinability

[0132] ㆍ When the intention is to expand a material having multiple voids (e.g., a network of voids), such as a foam (e.g., polyurethane), the following approximate list of additives is preferred for machining:

[0133] - Trimethyl citrate, pantolactone (racemic), diacetone acrylamide, methyl nicotinate - Hardness, melting point, processability, water solubility

[0134] - Crotonic acid - Hardness, melting point, machinability, water solubility, and precipitation from cold solution

[0135] As used in this specification, in the expression “contacting the material with the additive so that at least a portion of the additive is incorporated within at least a portion of the material’s multiple gaps (e.g., a network of gaps),” the term “contacting” refers to any process of bringing the material and the additive into close contact so that at least a portion of the additive is incorporated in this manner. In this context, the term "portion" may refer to at least 5%, e.g., at least 10%, e.g., at least 15%, e.g., at least 20%, e.g., at least 25%, e.g., at least 30%, e.g., at least 35%, e.g., at least 40%, e.g., at least 45%, e.g., at least 50%, e.g., at least 55%, e.g., at least 60%, e.g., at least 65%, e.g., at least 70%, e.g., at least 75%, e.g., at least 80%, e.g., at least 85%, e.g., at least 90%, e.g., at least 95%. The material may be completely saturated with the additive (100% incorporation of the additive into the gaps) or may not be completely saturated. This process may include the use of any one or more of the following: pouring; soaking; agitation; vibration; use of reduced pressure (e.g., by applying a vacuum); Use of increased pressure. These methods may involve the use of a combination of these techniques.

[0136] The use of reduced pressure may involve placing the material and additives within a vacuum chamber of a fixed volume or a vacuum chamber of a variable volume (e.g., a bag), after which the pressure in the chamber is reduced, causing the gas incorporated into the material to expand and escape from the material, which is then replaced by the additive. In one embodiment, the foam material is placed within a bag, the gaseous contents of the bag are removed by vacuum, the foam is compressed, and then the foam is allowed to expand so that the additive is introduced into the vacuum chamber, and / or the foam is made to expand to incorporate the additive. The additive may be introduced into the vacuum chamber through the same or a separate port in such a manner as the vacuum in the chamber is reduced and the material expands (e.g., by using a peristaltic pump). This vacuum method may be particularly useful when incorporating molten wax into the foam, but typically, in such an embodiment, it is desirable to ensure incomplete saturation. In some embodiments, a material having multiple voids (e.g., a network of voids), e.g., a foam, and a solid additive are placed in a vacuum bag; a vacuum is applied to the bag through an opening that compresses the material and extracts all or part of the air; subsequently, the outlet is sealed, and the vacuum bag is heated (e.g., by being placed in a heated liquid) to melt the additive, thereby causing the molten additive to be drawn into the material as it melts, and as a result, when the contents of the bag are returned to atmospheric pressure, a fully expanded material containing the additive throughout is produced. Some nominal advantages of this method are as follows: simple equipment construction requiring less space and reduced exposure to spills and hazards; improved repeatability and consistency by weighing the required additive; and improved reliability due to a reduction in the number of pipes requiring heating to prevent premature curing and clogging.

[0137] In some embodiments, the molded vacuum bag may be used to act as a mold so that a material having gaps (e.g., voids, e.g., foam) can be cooled and cured without being removed from the bag. The vacuum bag itself may be molded, or it may consist of one or more solid members having a shape (e.g., two solid plates connected by a silicone gusset or skirting; or one plate having a vacuum sheet with a sealed perimeter). When a vacuum is applied, it provides flat pressure over the material, and when the vacuum is released, it provides a flat surface on which the material can cool. In some cases, a bottom plate may serve as the intended working surface and be placed on a machine bed for molding. Alternatively, one or more plates may be molded (e.g., a mold). The nominal advantages are as follows: simple equipment construction requiring less space and reduced spill and risk exposure; Materials that remain consistently flat and square when cured (e.g., foams); reduced deformation when using two-plate setups on thinner sheets, as they can be smoothly fitted or / limited from warping; and / or possible reduction in process time and energy requirements for specific needs (when only smaller pieces are required or when large slab stock cannot be prepared).

[0138] In some embodiments, an additive may be used to expand a material having multiple voids (e.g., a network of voids). For example: a material (e.g., a foam) may be contacted with an additive that expands the material; the additive is cured so that the material is now in an expanded state; the material is molded; the additive is removed and the material returns to its original size. This method offers the nominal advantage of improving the penetration of very fine foams by increasing the overall size of the material and increasing the flow of the additive into the material; and improves processing resolution by molding to an enlarged size.

[0139] Another variation of the use of reduced pressure is to apply force to an elastic or viscoelastic material having multiple voids (e.g., a network of voids) so that the material compresses and expels at least a portion of the contents of the voids from the material. When the force is relieved, and in the presence of an additive, the material expands, and consequently, at least a portion of the additive is incorporated into the material. For example, the foam may be submerged in a bath or bag of liquid wax, and the foam may be compressed to expel any incorporated gas, and then the foam may be expanded to allow a portion of the liquid wax from the bath to be incorporated. In some embodiments, it is desirable to saturate the material with the additive, but in other embodiments, it is desirable to partially saturate the material with the additive. In this example, the amount of gas expelled may vary depending on the degree of compression of the material. The amount of gas present in the material may be controlled by various techniques, including removing the partially compressed material from the bath before the material is fully expanded. Another technique involves partially compressing the material so that a portion of the additive and a portion of the gas are incorporated into the product material. In a further technique, the material is soaked preferentially and unevenly, for example, from one side of the material, to ensure that the additive is incorporated into the material to a greater extent than in other parts of the material. It has been found that such methods can enable the user to produce a material incorporating a desired ratio of gas to wax. Similar method(s) may be applied to other materials and / or additives. As can be understood, the ability to compress elastic or viscoelastic materials having multiple voids (e.g., a network of voids) deviates significantly from the previous methods used for inelastic or non-viscoelastic materials.

[0140] Advantageously, the method of the present invention enables the adjustment of the amount of additive to be incorporated, and also the adjustment of the location where the additive is incorporated within the material. For example, the additive may be concentrated in specific areas to improve the method and / or article. For example, an amount of wax may be incorporated into the foam in an amount sufficient to simply coat the surfaces of the pores and fix most of the foam. As another example, an amount of wax may be incorporated only into the upper machined layer of the foam, thereby substantially rigidifying the material and providing a higher quality surface finish. By adjusting the amount of additive incorporated into the material, it is possible to reduce the amount of additive required, and consequently, facilitate easier removal of the additive.

[0141] Although the process of bringing materials into contact with additives has been described mainly for foams and waxes, the use of non-liquid additives is also considered. For example, additives that are granules, powders, or mixtures thereof, particularly when the additive is airborne, can be incorporated into the material by pouring or even by using reduced pressure.

[0142] As used herein, the expression “applying to the material a condition such that at least a portion of the incorporated additive solidifies, hardens, and / or hardens” means providing one or more external stimuli to change the conditions undergone by the material and the additive. Examples of such stimuli include magnetic, electrical, thermal, chemical, mechanical, and electromagnetic.

[0143] Typically, the stimulus will be a thermal stimulus, for example, a stimulus that causes a decrease in the temperature of the additive. For example, the stimulus may simply be a decrease in the temperature of the environment containing the additive (and the material incorporating the additive), which causes the temperature of the additive to decrease, thereby causing the additive to solidify, harden, and / or harden, as expected when wax changes from a liquid state to a substantially solid state.

[0144] As mentioned above, other examples of stimulation include: magnetic stimulation; the application of force (including shear), such as the application of high-frequency mechanical waves; or the application of electrical stimulation.

[0145] In some embodiments, it may be desirable to further manipulate the material prior to molding. Examples of manipulation may include: pressing, embossing, molding, folding, joining, splicing, and / or inserting the material pieces before the additive is cured or introduced. The purpose of these may include pre-forming a shape (e.g., a mold), smoothing a number of joined / joined material pieces, or pressing / compressing the material to reduce the amount of additive required. For example, pre-forming or compressing the material with the additive may be used to simplify and accelerate some operations. In such embodiments, for example, compression can typically occur in a positive mold (and mirror image) when replicating the shape—for example, to create a foam hemisphere, the mold will be a positive hemisphere, and when compressed into the foam, the highest point of the hemisphere will be the lowest or most compressed part of the foam, and will emboss an indentation into the foam. Accordingly, the process comprises the following steps: contacting the foam with an additive and then placing the foam in a mold that compresses and embosses the hemisphere at the center; curing the foam and the additive in the mold; the hemispherical embossing is substantially lower than the rest of the foam and, accordingly, excludes it from the cutting operation; In this case, when the foam is merely face-milled or planed to an embossing depth, the resulting foam will have a hemispherical shape that protrudes higher than the rest of the foam.In other embodiments, the process comprises the following steps: stamping a foam sheet with a liquid additive into a positive mold; curing the additive and maintaining a compressed state or embossment; cutting the material to remove uncompressed portions; heating the additive and removing the additive to reveal a positive replication of the mold. Such processes may be advantageous for rapidly creating a standard or approximate shape of an article before proceeding to further molding, or for easily creating textures that might otherwise take a long time to form. This can be used as an alternative to foam convoluting machines, provided that the shape is maintained until the additive is removed. As is estimated, additional advantages are as follows: more complex shapes can be formed; further machining of the compressed foam is possible; compression is not limited to rollers; Foam slab stock can be maintained at room temperature in a state having a compressed shape or texture prepared for further molding; this makes it possible to mass-produce items using the original method. A possible additional advantage of this is that pre-compressed foam blanks can contain, for example, the impression of a standard wheelchair seat. Thus, a basic shape can be provided by a single cutting pass, and then a shape for a specific customer can be customized by a calculated pass. This effectively reduces the required cutting depth, increases speed, and reduces the volume of additives. Furthermore, the compressed foam is not permanently formed until the foam material is removed by machining.For example, if a foam sheet having a convoluted embossing is heated, the foam can be restored to a conventional square foam sheet. If it is cut flat across, a convoluted sheet will be produced. Knowing the compressed shape and dimensions, it is possible to mold the foam beyond the impressed shape by compensation so that selected peaks of the convolution can be removed by machining the compressed portions; or convolution troughs can be removed by not machining the uncompressed portions. Overall, through these processes, the key methods of the present invention can be scaled from custom manufacturing to larger-scale mass production, with added flexibility and customization. In such embodiments, the compression process is, for example: compressing before cooling; partially saturating and cooling the foam, and then compressing and bonding the compressed cells; This can be done in a manner such as using a cold press to rapidly cure parts of the foam. Alternatively, this can be carried out using variations of the additives described above, each with its own advantages (powder, wax, dry powdering additive, etc.). As can be seen, these processes can be paired with the core methods of the present invention by using compression / embossing on one side and performing more complex machining on the opposite side.

[0146] Before and / or during the process of forming the material, the material is typically held firmly in place, and accordingly, for example, a movable forming device moves around the fixed material. Advantageously, certain embodiments of the present invention enable the material to be held firmly on the surface in such a manner that the material can be removed from the surface relatively easily upon completion of the forming process. In particular, a heated / cooled working surface may be used, such as one provided by hydronic heat transfer. If an additive, such as a wax, solidifies, hardens, and / or hardens upon a decrease in its temperature, the foam incorporating the additive may be placed on the surface at a given elevated temperature (typically exceeding the melting point of the wax) and may be held on the surface by reducing the surface temperature, for example, to below the melting point of the wax. As it appears, the material subjected to these conditions remains sufficiently held on the surface so that the forming process can take place. Upon completion of the forming process, the surface temperature may be increased, and the material may be loosened and removed and / or repositioned. Such technologies offer significant advantages over previously disclosed processes that require the use of clamps or strong adhesives (e.g., super glue), which are understood to damage the material and limit possible machining geometries.

[0147] As used herein, the expression “shaping the material” refers to any process in which a material is deformed from one shape to another. Typically, the present invention is best suited for subtractive shaping processes, including manual shaping and machining. Examples of machining processes include computer numerical control (CNC) machining, such as contour machining. Such machining includes the use of lathes, mills, turn-mills, multi-axis mechanical arms, multi-axis water jets, lasers, hot wires, sonic knives, reciprocating blades / saws, knives, and ablation tooling.

[0148] Preferably, the machining process will use CNC machining, which is an example of cutting machining having a definable tool depth or end. Such processes having a definable tool depth or end typically include spindles (mill and turn-mill) or a combination of a spindle and a feed non-rotating tool (lathe and turn-mill), ultrasonic tools (non-rotating cutters), reciprocating tools (reciprocating and concentric cutters), concentric rotary tools, and grinding / sanding / rasping / burr tools.

[0149] Such processes having a definable tool depth or end typically exclude processes such as lasers, water jets, plasma cutters and air jets, and band saws, chain saws and wire cutters that do not cut at a point on the guide or at its radius.

[0150] As used herein, the expression “removing at least a portion” of the incorporated additive refers to the following processes:

[0151] ㆍ Stirring the material containing the additive (e.g., shaking, vibration, compression (which may be slow or fast; which may be repeated several times in a compression / expansion cycle), or using centrifugal force) so that at least a portion of the additive is fragmented and becomes unmixed, allowing the unmixed additive to be separated at this stage;

[0152] ㆍ Submitting the material containing the additive into a liquid bath and then performing optional stirring (e.g., shaking, vibration, compression, or using centrifugal force). The liquid bath may be at a different temperature (e.g., warmer) than the material before being placed in the bath. The liquid may be a liquid that is immiscible with the additive. In one embodiment, the additive (e.g., wax) is melted and becomes immiscible, separating it from the material. For example:

[0153] - The wax-mixed material is placed in a bath of warm water and stirred so that the wax melts, separates from the material, separates from the warm water, and accumulates on the surface of the warm water;

[0154] - The wax-incorporated material may also optionally incorporate a surfactant mixed with the wax. When placed in a (optional warm) water bath and stirred, the wax melts and the surfactant is solvated to form an emulsion of wax and surfactant.

[0155] - The wax-incorporated material may be placed in a bath of (optionally warm) water containing a surfactant, and the material may be stirred, thereby separating the wax (optionally melted) from the material and emulsifying it in the water.

[0156] - The wax-incorporated material may be placed in a bath of a solvent (which can solvate the wax) (optionally warm), and the material may be stirred, and accordingly, the wax (optionally melted) is separated from the material and dissolved in the solvent.

[0157] ㆍ Stirring the material while it is exposed to heat (e.g., shaking, vibration, compression (which may be slow or fast; may be repeated multiple times in a compression / expansion cycle), or the use of centrifugal force) so that at least a portion of the incorporated additive is melted and discharged from the material. For example:

[0158] - In such an embodiment, this process may be performed by applying heat to a material containing an additive so that at least a portion of the additive is melted before the material is compressed to discharge most of the additive from the material;

[0159] - In another such embodiment, both heat and compression may be applied continuously until the desired level of additive is removed;

[0160] - In another such embodiment, the material may be placed in a bag, and the contents may be subjected to reduced pressure through a vacuum, and then heat may be applied to the bag to melt the additive, and the molten additive may be removed from the bag under vacuum.

[0161] As can be understood, additives can be partially or completely removed from a material using any one of the methods mentioned above. Typically, such methods partially remove additives from a material. In such embodiments, it may be desirable to remove residual additives using a secondary removal process. Such a secondary process includes any one or more of the above removal techniques. For example:

[0162] ㆍ Optionally, a solvent is applied to a material containing residual additives in combination with stirring (e.g., shaking, vibration, compression, or the use of centrifugal force).

[0163] After the step of removing at least a portion of the incorporated additives, an additional step of recovering the surfactant, wax, and water for reuse may be performed.

[0164] In the twelfth and thirteenth embodiments, the present invention provides a method for forming a molded elastic or viscoelastic material having a plurality of gaps (such as a network of voids), and the method comprises:

[0165] i. A step of forming a mixture by contacting an additive in a container with a resin capable of curing to form an elastic or viscoelastic material;

[0166] ii. A step of forming a homogeneous blend by, for example, degassing the mixture by vacuum and / or mixing the mixture;

[0167] iii. A step of curing the resin to form an elastic or viscoelastic material mixed with at least a portion of the additive;

[0168] iv. A step of molding a material mixed with an additive to form a molded material mixed with an additive; and

[0169] v. optionally, a step of removing at least a portion of the incorporated additive from the molded material in which the additive is incorporated; comprising,

[0170] Here, the additive is not water, and the additive solidifies, hardens, and / or hardens when a change in conditions selected from heat, magnetism, electricity, chemistry, and / or electromagnetics is applied.

[0171] This embodiment differs slightly from other embodiments in that the elastic or viscoelastic material is formed from a resin that is already in contact with an additive. However, it shares some similarities. In particular, the formed elastic or viscoelastic material formed by the above method may not be distinguishable from the elastic or viscoelastic materials formed by other methods disclosed herein. The resin method may provide specific advantages / disadvantages compared to the method of contacting the additive with the elastic or viscoelastic material.

[0172] Resins can shrink (due to heat, electromagnetic radiation, electricity, etc.), and thus, the foam shrinks after being molded to a larger size. The nominal advantages of this method include enabling the molding of microstructures that are too small to be machined by other means, and / or improving the accuracy of mechanical equipment (e.g., if molded to twice the size, the machining tolerance can be effectively doubled when the material finally shrinks). This resin technology can be applied in the following fields: development of implantable materials; soft robotics; reproduction of very small biological structures. In the case of soft robotics, the resin can be reversibly controllable and accordingly provide novel types of multicellular pumps or muscle analogs. This technology can also be paired with 3D printing, wherein: an additive is 3D printed to form desired gaps (e.g., a network of pores) and coated with resin; and the additive and resin are 3D printed. As can be seen, this tenth embodiment is fundamentally different from 3D printing of the shrinkable resin itself, because the method does not involve the use of additives and subsequent machining steps as defined in this specification.

[0173] In some embodiments, the additive may be aerated before bead formation, may have a sufficiently low vapor pressure, or may contain a mixture capable of releasing gas. In such cases, the process may include the following steps: combining a resin and an additive (e.g., beads); curing the resin; placing the additive-containing cured resin, having a skin sealed around its outside, into a vacuum chamber to produce a cured resin having the additive in the form of a foam in which the additive is incorporated as space holders; raising the temperature of the vacuum chamber so that the additive melts and the pressure is lowered (in this case, for an aerated additive, the trapped air expands to expand the cells within the foam); cooling and curing the additive to maintain the expanded state of the foam at normal atmospheric pressure; molding the expanded foam to break the sealed outer skin; and heating the material so that the additive can be removed and the foam can return to its original size.

[0174] Many of the aforementioned processes for removing additives advantageously prevent the use of hazardous solvents (compared to previously disclosed methods), and accordingly, reduce the risks, storage, and costs associated with solvents in previously disclosed methods.

[0175] Where solvents can be avoided, the present invention increases the diversity of materials suitable for the method, because while additives and removal methods do not damage the materials, solvent compatibility is not consistent across all materials (particularly foams).

[0176] An additional advantage is the ease of emulsification, particularly when the additive is incorporated into a mixture with a surfactant; thereby, the use of stirring combined with the proximity of the surfactant to the additive can eliminate the problem of solvent penetration when removing deeply embedded additives, such as those found in much larger articles.

[0177] The present invention offers many advantages over previously disclosed methods. Previously disclosed methods do not address their environmental impacts and do not disclose any advanced solutions. In contrast, the present invention enables the recovery of additives and, accordingly, provides an advanced environmental and sustainable method. For example, the ease of extracting and recovering additives enables the reuse of additives, materials, and solvents (including water) in a closed-loop system. It has been found that the use of additives derived from sustainable renewable resources can provide improvements regarding environmental and sustainability issues. An additional advantage is that the present invention can be adapted in a manner that improves adoptability, quality, time, and cost related to storage and facilities by contracting one or more process steps to a third party. One such method is to license a third party to perform the step of incorporating additives into materials in order to reduce costs, increase quality, and improve consistency. The manufactured materials can be delivered as needed to a party intending to perform the molding of the materials and the removal of the additives. Then, a third party can collect the additives, manufacture new materials, and efficiently recycle the foam waste materials. If necessary, the third party can perform further processing of the additives or, if required, reformulating. This enables small businesses to adopt this method and also allows the handling of additives to be entrusted to larger companies or emerging parties specializing in the handling and formulation of additives and the handling of any waste materials.

[0178] Another adaptation to the reduction of material waste promoted by the present invention may be the manufacture of shaped foam blanks for machining, such as foam seating orthoses blanks, which can be machined according to specific requirements instead of machining in bulk from square foam blocks to achieve the same shape as an orthosis blank.

[0179] Another advantage of the present invention is the control of particulate materials (e.g., dust) during machining, which eliminates the need for extraction equipment, because additives bind to waste materials during machining and, accordingly, effectively encapsulate the particulate materials to remove most of the airborne particles.

[0180] An advantage over other methods of producing molded materials (e.g., foam articles) is the reduction in storage space required for storing large storage areas or molds that require remanufacturing from CAD files.

[0181] An additional advantage is the ability to manufacture materials incorporating additives and to store the manufactured materials for extended periods without the need for specific storage conditions (e.g., low-temperature storage required in some previously disclosed methods). In this way, the stockpiling of manufactured materials (e.g., foams) can be carried out in large slabs or in predetermined sizes and shapes. Since pieces can be taken from the slabs only when necessary, the economics of cutting to reduce waste is improved. Furthermore, by enabling a third party to manufacture the materials and supply them to companies that intend to mold the manufactured materials, the cost of necessary equipment and space can be further reduced.

[0182] The present invention may also utilize 3D modeling. In methods departing from traditional mold-making methods, the use of minimal or non-contact 3D measurement, mapping, and / or tracking may be utilized to generate data that can be manipulated using CAD / CAM methods and subsequently output into a form for machining. 3D measurement, mapping, and tracking may consist of typical medical imaging such as: MRI, CT, X-ray, or ultrasound, or 3D scanning, motion tracking and mapping techniques, or pressure mapping and impression mapping.

[0183] <Example>

[0184] The following embodiments of the present invention are not exhaustive and are provided merely for illustrative purposes.

[0185] An open-cell soft foam block (2) (an example of an elastic or viscoelastic material having a network of pores) is provided to be formed by machining. In one embodiment, the block (2) may be saturated in a mold (4) for complete incorporation of an additive. The mold may have an open bottom (10) that allows the block to be fixed to a machine bed, or the mold may have a closed bottom (12) that allows the block to move around after the additive has been incorporated, separately from the machine bed. In either case, the block may optionally perform partial addition / removal of any additive through the use of a plunger (16). The mold may then be fixed to a machine bed (20) or separated from the machine bed (22) and removed from the molded article. When the additive-mixed material (22) is separated from the machining bed, the additive-mixed material (22) may subsequently be fixed to the machining bed through a separate heating step to remelt a portion of the wax (26) and fix it to the machining bed. In another embodiment, the block (2) may be in contact with hot molten wax in a bath (6), for example, at 50 to 80°C, and optionally may be stirred by compression (14) using a plunger. Then, the foam material may be removed from the bath and, if intended to allow partial saturation, may be allowed to discharge excess additive (18). An optional secondary saturation step of one aspect (face) of the foam material (24) may be provided. In any case, the foam material can be fixed to the machined surface through a separate heating step to remelt a portion of the wax (26) and fix it to the machined bed.In another embodiment, the block (2) may be placed in a vacuum-applied bag (8) to reduce the air within the foam before hot wax is pumped in to fill the air space and uniformly saturate the foam. When the foam material is removed from the bag, the foam material may be fixed to the machining surface through a separate heating step to remelt a portion of the wax (26) and fix it to the machining bed.

[0186] The fixed material (28) can be machined using various processes. In one embodiment, the material can be machined by single-sided machining (30), and the resulting article can be removed from the machining bed by applying heat (34). In another embodiment, the material can be machined by double-sided machining (32), which is achieved by leaving a boundary to create a trough. The trough (36) can be filled with wax or even a wax / waste (44) slurry before the upper surface is machined to a flat level. Then, the piece (38) can be heated to remove the piece from the bed (40), and then rotated and re-annealed (42) to become a machined surface. Next, the rotated piece can be machined (46) to become a double-sided machined article (48) and removed from the machined bed (50).

[0187] In any embodiment, the material may be placed in a high-temperature wax bath (52) to remelt the additive. To remove most of the wax, removal and stirring (compression) may be applied (54). Alternatively, the material may be placed in a vacuum and heat-applied bag to remove the melted wax from the foam material. The finished piece (58) may be volumetrically removed, or the wax residue may remain to impart some water-repellent, condition-regulating, and / or antibacterial properties. Cleaning may be performed using: a warm detergent (surfactant) solution in a bath; an ultrasonic bath using detergent and heat; with a continuous flow of hot water or detergent; or a warm detergent bath with a stirrer or compression. Alternatively, residual wax may be recovered using a solvent through any of the aforementioned related methods.

[0188] As shown in FIG. 4, the methods of the present invention may be applied to a plurality of formed raw materials (60) as shown in step 1A; or to a formed blank (62) to be customized or machined to a tolerance; or to a previously formed material to be reprocessed as shown in step 1B.

[0189] FIG. 5 illustrates an example of the method of the present invention. In particular, step 1C illustrates an alternative process in which a solid additive (64) is used to form voids in the material produced when the additive is removed. Step 1 includes placing the solid additive (64) into a container (66). Step 2 includes adding a bulk elastic / viscoelastic material (68). Step 3 includes, if preferred, degassing or mixing of the additive and the aforementioned bulk material, and curing, hardening, and setting of the bulk material after maintaining it in the original container or transferring it to another container. Step 4 includes molding the cured bulk material / additive mixture. Step 5 includes completing molding or additional molding operations to achieve a desired shape. Step 6 includes heating (70) of the additive, which can be performed in various ways, with or without a vacuum bag. Step 7 includes removing additives by vacuum (72) and / or compression (74) means. Step 8 provides a finished article. If desired, additional cleaning or treatment may be performed.

[0190] As a specific example of this method, molten paraffin wax is dropped dropwise into a cold water bath at a constant rate to rapidly cool and form approximately spherical beads. The paraffin is dropped from a height sufficient to form individual droplets but not high enough to produce irregularly shaped fragments (e.g., flat splatter shapes). A bath with a constant circulation flow moves the paraffin beads away from the release point, minimizing fusion and aggregation of the beads. The paraffin beads are removed from the bath and dried. The beads are placed in a rectangular container, and a two-component addition-curing silicone is prepared and added to the container. The container containing the uncured silicone and beads is placed in a vacuum chamber, and depressurization is applied to remove undesirable pockets of trapped air. The container is removed from the vacuum chamber, and the silicone is left to cure. Once cured, the silicone containing the paraffin beads is removed from the container to create a rectangular silicone block incorporating the paraffin beads. The rectangular block is attached to the workbench of a CNC router and machined into the desired shape. The machining process breaks down the outer skin of the silicone, enabling the removal of paraffin additives. The molded piece is heated and compressed to melt and remove the paraffin. Unwanted residues can be removed using detergent washing. The final product is a formed open-cell elastic silicone foam.

[0191] In some embodiments, the additive beads may be selected from a variety of suitable materials including waxes, wax-like polymers, salts, sugars, sugar alcohols, etc. The described silicone 'resin' may be replaced with various polymers characterized by properties such as elasticity / viscoelasticity, resilience, softness, flexibility, etc. In an illustrative sense, 'curing' may describe various known methods depending on the base material, for example, the following: drying, crosslinking by electromagnetic radiation, heat, or synthesis.

[0192] Additionally, the additive may have secondary properties or be manipulated in a manner that alters the final article. For example, the additive may be whipped to incorporate air into the mixture before producing the molded beads, so that the solid molded beads may contain a portion of air throughout. Next, the silicone around the beads is cured, and subsequently, the cured silicone is heated to melt the paraffin bead(s). Then, the heated silicone is placed in a vacuum chamber. A vacuum is applied, and the bubbles dispersed throughout the additive expand. The skin formed around the outside of the silicone prevents air from escaping the silicone material block, thereby causing the silicone material block to expand in size. The silicone piece is then cooled in an expanded state to maintain its shape. Next, the silicone piece is machined, and the additive is heated and removed once again, allowing the silicone piece to return to its original size. This process preferably includes the following events:

[0193] ㆍ The formulation or melting of additives in a manner that prevents bubbles from clumping and maintains an expanded state;

[0194] ㆍ The expansion of silicone uniformly or predictably without damaging the outer skin;

[0195] The strength of the additive during expansion is sufficient to maintain the expanded state of the silicon for machining.

[0196] FIG. 6 illustrates various embodiments of the method of the present invention, comprising the step of contacting a foam with an additive:

[0197] Step 2A includes the following multiple substeps:

[0198] ㆍ Substep 1 includes placing the foam (76) from FIG. 4 (step 1A or 1B) into a vacuum bag (78);

[0199] ㆍ Substep 2 includes removing air partially or wholly to compress the foam;

[0200] ㆍ Substep 3 includes introducing an additive (80) to come into contact with the foam. This may be due to the negative pressure of the foam being expanded or injected by other means, such as a pump, syringe, or other suitable means;

[0201] ㆍ Substep 4 provides an additive to the generated foam.

[0202] Step 2B includes the following multiple substeps:

[0203] ㆍ Substep 1 comprises a foam (82) placed in a container containing an additive (84, e.g., the additive is heated to a liquid state), and a suitable press (86);

[0204] ㆍ Substep 2 includes compressing the foam to expel all or part of the internal air;

[0205] ㆍ Substep 3 includes releasing the press so that the additive can flow into the cell.

[0206] Step 2C includes a number of substeps:

[0207] ㆍ Substep 1 includes placing the foam (88) in a suitable vacuum bag (90) or similar container while the additive (92) is in a solid state;

[0208] ㆍ Substep 2 includes applying a vacuum to remove air and compressing the foam to produce a solid additive and a compressed foam;

[0209] ㆍ Substep 3 comprises heating the additive and the foam by suitable means while still in an airless or partially airless state;

[0210] ㆍ Substep 4 includes drawing the additive into the compressed foam (when it becomes a liquid) to produce an uncompressed foam in which the additive is incorporated.

[0211] Figure 7 shows a process similar to that shown in step 2B, where the container acts as a mold:

[0212] Step 2D includes the following multiple substeps:

[0213] ㆍ Substep 1 includes placing the foam (94) in a container (96) comprising an additive (98; e.g., the additive is heated to a liquid state) and a suitable press (100);

[0214] ㆍ Substep 2 includes compressing the foam to expel all or part of the internal air;

[0215] ㆍ Substep 3 includes cooling the foam / additive in the container after releasing the press to allow the additive to flow into the cell;

[0216] ㆍ Substep 4A shows that the container or the bottom of the container is an intended workbed or bed to which it is attached to a machine bed. The side (102) of the container can be optionally removed;

[0217] ㆍ Substep 4B includes removing the hardened foam (104) from the container.

[0218] FIG. 8 shows a process in which solid granules, powders, etc. are additives and can be manipulated by external stimuli (solid or other methods) optionally or if necessary.

[0219] Step 2E includes multiple substeps:

[0220] ㆍ Substep 1 includes applying the additive (106) as a solid granule to a foam (108) placed in a container that is stirred to promote the movement of the additive into the foam.

[0221] ㆍ Substep 2 shows the additives in the foam.

[0222] ㆍ Substep 3A includes molding the foam and additives in a container into a significantly harder composite material.

[0223] ㆍ Substep 3B shows an additive that undergoes a magnetorheological change, in which individual granules are held significantly more rigidly or their movement is restricted by a magnetic field applied near the container.

[0224] ㆍ Substep 3C shows an additive that undergoes magnetorheological changes, in which individual granules are held significantly more rigidly from movement on a workbench or machine bed by a magnetic field.

[0225] ㆍ Substep 4 shows a molded foam being stirred to remove additives, which can be further enhanced by applying a magnetic field to help attract and collect additives while further separating waste from the additives. This can be performed in a bath or dried elsewhere.

[0226] Figure 9 shows a method of changing the properties of an additive by adding or removing heat.

[0227] Step 3A includes a number of substeps:

[0228] ㆍ Substep 1 comprises concentrating the additive (110) in a desired area of ​​the foam by: cooling the additive and the foam (112) by orientation; cooling with significantly more additive in the area of ​​interest; or reapplying to a desired area of ​​the already cured foam;

[0229] ㆍ In sub-step 2 (in the case of reduced additive requirements), the additive can be concentrated in the area to be machined to improve molding.

[0230] In step 3B, excess additive (114) can be drained or compressed to a desired amount.

[0231] In step 4A, the foam can be left to harden and be fixed to the work surface.

[0232] In step 4B, the foam can be cured in a vacuum bag or other suitable container (including the container from step 3A), and this container can be molded to become a mold.

[0233] In step 4C, the foam can be cured by other means before being attached to the work surface.

[0234] Step 5 includes the following substeps:

[0235] Substep 1 includes attaching a cured foam to a work surface by heating the work surface, or by applying a molten additive to the work surface with or without a heated surface to adhere the foam.

[0236] ㆍ Substep 2 includes cooling the work surface to attach the foam or allowing it to cool without further cooling. Alternatively, the foam may be attached by any other means, such as standard work holding, such as a chuck, vise, clamp, or vacuum holding.

[0237] FIG. 10 illustrates, as an example, a method by which the process of FIG. 9 can be continued.

[0238] Step 6A (1) includes molding a foam (116).

[0239] Step 6B illustrates a method for machining multiple faces, comprising the following substeps:

[0240] ㆍ Substep 1 includes applying an additive (118) to previously created surfaces or molded troughs and then curing them.

[0241] ㆍ Substep 2 includes orienting it upward so that it becomes flat or shaped (e.g., for other mounting methods such as pegs, vises, or interlocking members).

[0242] ㆍ In sub-step 3 (in the case of a foam attached by an additive), the bed is heated and the workpiece (120) is repositioned.

[0243] ㆍ In sub-step 4 (in the case of adhesion by additive), the workpiece is placed and the workbench is cooled.

[0244] ㆍ Substep 5 includes forming the repositioned workpiece.

[0245] ㆍ Substep 7 includes removing the molded foam from the work surface by applying heat.

[0246] Figure 11 illustrates the removal of additives.

[0247] Step 8A includes the following substeps:

[0248] ㆍ Substep 1 comprises heating the molded foam (122) by suitable means, for example, by conduction in a container of water or liquid additive or by radiant heat;

[0249] ㆍ Substeps 2, 3, and 4 show that the heated molded foam is compressed by suitable means.

[0250] Step 8B includes the following substeps:

[0251] • Substep 1 shows that the molded foam (124) is placed in a suitable vacuum bag or array, as described in the introduction to this description. The molded foam is heated by suitable means as described in step 8A. To improve this step, a vacuum may be applied before and during heating.

[0252] • Substeps 2 and 3 show applying a vacuum to remove additives and then releasing the vacuum to allow the foam to expand. Optionally, the bag may be compressed by other means.

[0253] An additional step of washing or removing residue may be desirable.

[0254] Figures 12 and 13 show how the addition or removal of heat can be used to change the properties of an additive.

[0255] Step 2F includes the following multiple substeps:

[0256] ㆍ Substep 1 comprises placing a foam (126) in a container (128) comprising an additive (130; for example, the additive is heated to a liquid state) and a suitable press (132);

[0257] ㆍ Substep 2 includes compressing the foam to release all or part of the air inside it;

[0258] ㆍ Substep 3 includes releasing the press to allow the additive to be drawn into the cell;

[0259] ㆍ Substep 4 includes compressing the foam with a mold (134);

[0260] ㆍ Substep 5 includes cooling the foam / additive while being compressed by a mold inside a container;

[0261] ㆍ Substep 6 shows a cured foam having a mold impression;

[0262] ㆍ Substeps 7 and 8 include removing the foam material using a surface machining operation (molding);

[0263] ㆍ Substep 9 comprises heating the molded foam by suitable means, for example, by conduction within a container of water or liquid additive, or by radiant heat;

[0264] ㆍ Substep 10 includes compressing the heated foam / additive;

[0265] ㆍ Substep 11 shows the resulting foam that displays the shape of the mold.

[0266] Unless the context clearly requires otherwise, throughout the description of the invention and the claims, words such as "include," "including," etc., should be interpreted in a comprehensive sense, not in an exclusive or conclusive sense—that is, in the sense of "including but not limited thereto."

[0267] If any, the full disclosures of all applications, patents, and publications cited above and below are incorporated herein by reference.

[0268] Any reference to any prior art in this specification is not, and should not be construed as, an acknowledgment or any form of implied that the prior art forms part of the ordinary general knowledge in the field of endeavor of any country in the world.

[0269] The present invention may also be roughly described as being composed of parts, elements, and features mentioned or indicated in the specification of this application, individually or collectively, any or all combination of two or more of said parts, elements, or features.

[0270] Where references to components having integers or known equivalents thereof are made in the preceding description, such integers are incorporated into this specification as if they were described individually.

[0271] As should be noted, various changes and modifications to the preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the invention and without diminishing the accompanying advantages. Accordingly, such changes and modifications are intended to be included in the invention.

Claims

Claim 1 A method for shaping an elastic or viscoelastic material having a plurality of interstices, the method comprising: i. providing an elastic or viscoelastic material having a plurality of interstices; ii. bringing the material into contact with an additive such that at least a portion of the additive is incorporated into at least a portion of the plurality of interstices of the material; iii. applying a condition to the material such that at least a portion of the incorporated additive is solidified, hardened, and / or stiffened; iv. forming the material in which the solidified, hardened, and / or stiffened additive is incorporated using a subtractive shaping process to form a formed material in which the additive is incorporated, wherein the subtractive shaping process is performed using computer numerical control (CNC) machining; and v. A method comprising the step of removing at least a portion of the incorporated additive from the molded material into which the said additive is incorporated; wherein the additive is solidified, hardened, and / or hardened at a temperature greater than 0°C. Claim 2 The method of claim 1, wherein the elastic or viscoelastic material is selected from foams and / or sponges, felts, lattices, scaffolds, coiled materials, meshes, and / or webs. Claim 3 In claim 1, the elastic or viscoelastic material is a foam, method. Claim 4 A method according to any one of claims 1 to 3, wherein the additive is selected from: waxes or wax-like compounds and mixtures thereof; crystalline solids / supersaturated liquids; liquid crystal compounds; solidifying non-Newtonian compounds; granules / powders / other solids that can flow into the elastic or viscoelastic material; and liquids and / or solids that can be hardened or arranged and oriented to be further rigidified by other means. Claim 5 A method according to any one of claims 1 to 3, wherein the additive is a wax or a wax-like compound. Claim 6 A method for forming an elastic or viscoelastic material having a plurality of gaps in which the additive is incorporated, using a solid, hard and / or rigid additive at a temperature greater than 0 ℃, wherein the elastic or viscoelastic material is formed by a subtractive shaping process before at least a portion of the additive is removed from the elastic or viscoelastic material, and the subtractive shaping process includes CNC machining. Claim 7 A contoured elastic or viscoelastic material having a plurality of gaps, wherein at least a portion of the material has an additive incorporated into the material, said additive is solid, hard, and / or rigid at a temperature greater than 0°C, and said material is manufactured according to the method of any one of claims 1 to 3. Claim 8 In claim 1, the method wherein the plurality of gaps are a network of voids. Claim 9 delete Claim 10 delete Claim 11 delete Claim 12 delete Claim 13 delete Claim 14 delete Claim 15 delete Claim 16 delete Claim 17 delete Claim 18 delete Claim 19 delete Claim 20 delete

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