Method for molding materials and molded products

Abstract

The present invention relates to methods for molding materials having a plurality of interstices (such as a network of voids) and molded products formed thereby. In a preferred embodiment, the material is a foam, such as polyurethane foam. The molding method allows such materials to be molded using contouring fabrication methods, including computer numerically controlled (CNC) milling, which is provided by way of example only. In contrast to methods that produce molded materials (such as by polymerization of a solution or emulsion of monomers), in some aspects the present invention contemplates molding pre-existing (preformed) materials having a plurality of interstices, such as a network of voids.

Description

Detailed Description of the Invention ,

[0003]

[0001] [Field of the Invention] The present invention relates to a method of forming a material having a plurality of gaps (such as a void network) and a formed product formed by said method. In a preferred embodiment, the material is a foam such as a polyurethane foam. The forming method uses a contour machining method including computer numerical control (CNC) milling provided only as an example, to enable such a material to be formed. To contrast with methods of producing a formed material (such as by polymerization of a monomer solution or emulsion), in some aspects, the present invention contemplates forming an existing (preformed) material having a plurality of gaps such as a void network.

[0002] [Background of the Invention] The assembly of flexible foams is the means by which the foam is formed either by shaping a foam stock or casting a resin system (except for casting of foam stock intended for assembly) for the desired end result. Forming methods include hand forming; and computer numerically controlled forming, examples being CNC mills, lathes, rotary mills and multi-axis robotic arm forming.

[0003] Materials such as polyurethane foams are well known for being difficult to accurately form. It is relatively easy to cut such a foam using a blade, saw, etc., or if one attempts to contour such a foam using conventional machining methods (such as computer numerical control (CNC) methods), it causes inaccurate contours and generally undesirable machining finishes. In particular, the inventor believes that the poor finish is caused by deformation of the foam by the machining tool during the forming process, causing material cutting at incorrect locations or even cracks. Instead of generating a smooth surface, such machining generates a rough surface.

[0004] Despite these challenges, molded polyurethane foam is widely used as padding for seats, mounts, and other applications. Often, users desire precisely molded polyurethane products for applications such as wheelchair seats, when a custom-molded product is required.

[0005] There have been few attempts to overcome the problems described herein. Generally speaking, the methods used so far may be classified as follows: Cryogenic method. This machining method is relatively fast and accurate, achieving the desired results at the expense of higher equipment costs (it must be able to withstand extreme temperatures), handling, storage, and excessive use of liquefied gas coolants, while also being mitigating exposure to fine foam dust and the hazards of liquefied gases. Liquid freezing method. This method involves saturating a foam with water and then freezing the water in situ. Freezing is a simplified version of the cryogenic method, enabling a lower, comparable cost for low-temperature dry machining by maintaining a sufficiently low temperature using frozen water. However, this method requires the water to remain frozen throughout all stages of the molding process for optimal results (which can be aided by cooling of the foam and water). The expansion of water leads to micro-destruction of the foam when it solidifies. Furthermore, the expansion of water within the foam at a lowered temperature can disrupt the tolerance of machining in an unpredictable way, as it can lead to suboptimal machining quality and precision, coupled with the loss of melting ice around the molded surface when high-speed, frictional machining tools come into contact with the surface. Another problem with this method is the need to include water, and the fact that the machined parts must be compatible with water to avoid corrosion, electrical failure, and leakage; and Dry machining method. This method refers to techniques other than the low-temperature method and liquid freezing described above, and requires long machining times, high-end equipment and machine tools, exposes technicians to harmful dust, but only provides limited shapes and dimensions.

[0006] Due to the limitations of these methods, particularly the potential health risks associated with the generation of very fine particles, traditional manual molding methods continue to be widely used in foam assembly.

[0007] Apart from the formation of flexible foams, it is often desired to shape porous metal materials that are normally inflexible. Compared to flexible foams, such materials present various problems. For example, machining porous metal materials sometimes produces burrs whose size and shape vary depending on the temperature and material used. At high temperatures, the contact points between the cutting tool and the metal become softer, causing a tendency for plastic dislocations to occur, resulting in the formation of smear or burrs in the metal. Such temperatures also accelerate the dulling of the machining tool. To overcome these problems, it is possible to apply coolants that lower the material temperature to harden the metal, producing cleaner cuts and preventing burrs, smears, and associated damage. Further teaching in the field of porous metal machining clarifies the problem resulting from ductile shear, and the solution to smearing depends primarily on achieving "brittle shear" using low-temperature methods.

[0008] As with all machining methods, in the methods described so far, it is necessary to ensure that the material to be molded is held securely during the molding process. Traditionally, materials are attached by clamping or otherwise by the use of adhesives such as cyanoacrylate or similar "super glue" adhesives. Such techniques generally damage the material either by the direct mechanical action of the clamp or as a result of the excessive force required to break the bond with the adhesive.

[0009] The object of the present invention is to address one or more of the aforementioned problems, or to provide a useful choice to at least an experienced reader.

[0010] [Overview of the prefecture] In a first embodiment, the present invention relates to a method for forming an elastic or viscoelastic material having a plurality of gaps, i. A step of preparing an elastic or viscoelastic material having multiple gaps; ii. The step of bringing the material into contact with the additive such that at least a portion of the additive is incorporated into at least a portion of the plurality of voids in the material; iii. A step of subjecting the material to conditions such that at least a portion of the incorporated additives solidifies, hardens, and / or stiffens; iv. The step of molding the material incorporating the solidified, hardened and / or rigidified additive to form a molded material incorporating the additive; and v. The step of removing at least a portion of the incorporated additive from the molded material that incorporates the additive. Includes, The additive solidifies, hardens, and / or stiffens at temperatures above 0°C. Provide a method.

[0011] In some embodiments, the elastic or viscoelastic material having multiple gaps is an elastic or viscoelastic material having a network of voids.

[0012] Therefore, in a second embodiment, the present invention relates to a method for forming an elastic or viscoelastic material having a void network, i. A step of preparing an elastic or viscoelastic material having a void network; ii. The step of bringing the material into contact with the additive such that at least a portion of the additive is incorporated into at least a portion of the void network of the material; iii. A step of subjecting the material to conditions such that at least a portion of the incorporated additives solidifies, hardens, and / or stiffens; iv. The step of molding the material incorporating the solidified, hardened and / or rigidified additive to form a molded material incorporating the additive; and v. The step of removing at least a portion of the incorporated additive from the molded material that incorporates the additive. Includes, The additive solidifies, hardens, and / or stiffens at temperatures above 0°C. Provide a method.

[0013] The method of the present invention enables the production of molded elastic or viscoelastic materials having a desirable surface finish. The method utilizes an additive that solidifies, hardens, and / or stiffens at a temperature above the freezing point of water (0°C at standard atmospheric pressure, 101.325 kPa). The additive is incorporated into the material so that it can be molded while the additive solidifies, hardens, and / or stiffens, thereby preventing undesirable deformation of the material.

[0014] For example, in some embodiments, the additive is wax, and the elastic or viscoelastic material having multiple voids (such as a network of voids) is a polyurethane foam. In those embodiments, the method may involve incorporating molten wax in a material that solidifies when cooled to room temperature, and the foam may then be molded by CNC milling. At least a portion of the wax is then removed from the molded foam.

[0015] While we do not wish to be constrained by theory, this method is thought to make it possible to shape materials without substantially altering the elastic modulus of the material itself. Furthermore, additives may be selected such that the temperature difference between the liquid and solid states of the additives is limited, and if any, the shrinkage of the material is very limited. Moreover, by carefully adjusting the amount of additives incorporated into the material, it is possible to avoid material saturation and, as a result, provide greater control over potential expansion or contraction.

[0016] Furthermore, while previously published methods of low-temperature technology weaken and damage the structure of foam materials at the molecular level to achieve machining, the present invention is thought to provide a mechanical advantage over the benefits of machining tools by focusing the shear force between the high momentum of the rotating cutting blade of the tool and the large inertia of the immobilizing additive (especially wax).

[0017] Therefore, the present invention represents a significant improvement over previously published methods, as it enables the molding of elastic or viscoelastic materials at room temperature and other temperature ranges above the freezing point of water. The advantages of the present invention are further enhanced by the self-healing properties of the additives used in some embodiments. For example, any additive (such as wax) that is temporarily melted by a machining tool will then harden after the tool has moved and passed through it, thereby once again contributing to the rigidity of the material. The use of wax-based additives can also lubricate the machine and cutting tools for increased service life, and it can reduce the risk of electrical failures that would otherwise be possible if water were used in previously published liquid freezing methods.

[0018] In a third embodiment, the present invention provides a molded elastic or viscoelastic material having a plurality of gaps (such as a void network) prepared by the method of the first or second embodiment.

[0019] In a fourth embodiment, the present invention provides the use of an additive that solidifies, hardens, and / or stiffens at temperatures above 0°C for forming an elastic or viscoelastic material having a plurality of gaps (such as a network of voids) into which the additive is incorporated.

[0020] In a fifth embodiment, the present invention provides a contoured elastic or viscoelastic material having a plurality of gaps (such as a network of voids), wherein at least a portion of the material has an additive incorporated into the material, the additive solidifies, hardens and / or stiffens at a temperature above 0°C.

[0021] As used herein, the term “contoured” refers to a form of an article that has been subjected to contouring, contour machining, 3D machining, or 3D contour machining techniques.

[0022] In a sixth embodiment, the present invention relates to a method for forming an elastic or viscoelastic material having a plurality of gaps, i. A step of preparing an elastic or viscoelastic material having multiple gaps; ii. contacting the material with the additive such that at least a portion of the additive is incorporated within at least a portion of the plurality of voids of the material; iii. subjecting the material to conditions such that at least a portion of the incorporated additive solidifies, cures and / or rigidifies; iv. shaping the material incorporating the solidified, cured and / or rigidified additive, thereby forming a shaped material incorporating the additive; and v. removing at least a portion of the incorporated additive from the shaped material incorporating the additive comprising, providing a method wherein the additive is not water and the additive solidifies, cures and / or rigidifies when exposed to a change in conditions selected from thermal conditions, magnetic conditions, electrical conditions, chemical conditions and / or electromagnetic conditions.

[0023] In a seventh aspect, the invention is a method of shaping an elastic or viscoelastic material having a network of voids, comprising i. providing an elastic or viscoelastic material having a network of voids; ii. contacting the material with the additive such that at least a portion of the additive is incorporated within at least a portion of the network of voids of the material; iii. subjecting the material to conditions such that at least a portion of the incorporated additive solidifies, cures and / or rigidifies; iv. shaping the material incorporating the solidified, cured and / or rigidified additive, thereby forming a shaped material incorporating the additive; and v. removing at least a portion of the incorporated additive from the shaped material incorporating the additive comprising, providing a method wherein the additive is not water and the additive solidifies, cures and / or rigidifies when exposed to a change in conditions selected from thermal conditions, magnetic conditions, electrical conditions, chemical conditions and / or electromagnetic conditions.

[0024] In some embodiments, the elastic or viscoelastic material having multiple gaps is an elastic or viscoelastic material having a network of voids.

[0025] In an eighth embodiment, the present invention relates to a method for forming an elastic or viscoelastic material having a void network, i. A step of preparing an elastic or viscoelastic material having a void network; ii. The step of bringing the material into contact with the additive such that at least a portion of the additive is incorporated into at least a portion of the void network of the material; iii. A step of subjecting the material to conditions such that at least a portion of the incorporated additives solidifies, hardens, and / or stiffens; iv. The step of molding the material incorporating the solidified, hardened and / or rigidified additive to form a molded material incorporating the additive; and v. The step of removing at least a portion of the incorporated additive from the molded material that incorporates the additive. Includes, The present invention provides a method for causing an additive to solidify, harden, and / or stiffen when exposed to changes in conditions selected from magnetic, electrical, chemical, and / or electromagnetic conditions.

[0026] In a ninth embodiment, the present invention provides a molded elastic or viscoelastic material having a plurality of gaps (such as a void network) prepared by the method of the fifth or sixth embodiment.

[0027] In a tenth embodiment, the present invention provides a use of an additive for forming an elastic or viscoelastic material having a plurality of voids (such as a network of voids) into which the additive is incorporated, wherein the additive solidifies, hardens and / or stiffens when exposed to changes in conditions selected from magnetic, electrical, chemical and / or electromagnetic conditions.

[0028] In an eleventh embodiment, the present invention provides a contoured elastic or viscoelastic material having a plurality of gaps (such as a network of voids), wherein at least a portion of the material has additives incorporated into the material, and when exposed to changes in conditions selected from magnetic, electrical, chemical, and / or electromagnetic conditions, the additives solidify, harden, and / or stiffen.

[0029] In a twelfth aspect, the present invention relates to a method for forming a molded elastic or viscoelastic material having a plurality of gaps, i. A step of bringing an additive into contact with a resin that can be cured to form an elastic or viscoelastic material in a container to form a mixture; ii. The step of degassing the mixture by vacuum or the like, and / or mixing the mixture to form a homogeneous blend; iii. A step of curing the resin to form an elastic or viscoelastic material that incorporates at least a portion of the additive; iv. The step of molding a material incorporating the additive to form the molded material incorporating the additive; and v. Optionally, the step of removing at least a portion of the incorporated additive from the molded material into which the additive is incorporated. Includes, If the additive is exposed to changes in conditions other than water, selected from thermal, magnetic, electrical, chemical, and / or electromagnetic conditions, the additive will solidify, harden, and / or stiffen. Provide a method.

[0030] In a thirteenth aspect, the present invention relates to a method for forming a molded elastic or viscoelastic material having a void network, i. A step of bringing an additive into contact with a resin that can be cured to form an elastic or viscoelastic material in a container to form a mixture; ii. The step of degassing the mixture by vacuum or the like and / or mixing the mixture to form a homogeneous blend; iii. A step of curing the resin to form an elastic or viscoelastic material that incorporates at least a portion of the additive; iv. The step of molding the material incorporating the additive to form a molded material incorporating the additive; and v. Optionally, the step of removing at least a portion of the incorporated additive from the molded material into which the additive is incorporated. Includes, If the additive is exposed to changes in conditions other than water, selected from thermal, magnetic, electrical, chemical, and / or electromagnetic conditions, the additive will solidify, harden, and / or stiffen. Provide a method.

[0031] Further aspects of the present invention should be considered in all its novel forms, and will become apparent to those skilled in the art by reading the following description, which provides at least one example of a practical application of the present invention.

[0032] One or more embodiments of the present invention are described below with reference to the following drawings, without any intention to limit them, and are merely illustrative examples. [Brief explanation of the drawing]

[0033] [Figure 1] This diagram shows a schematic flowchart illustrating the process of incorporating a wax additive into a foam material and fixing that material to a machined surface. [Figure 2] This figure shows a schematic flowchart of the machining process for one or both sides of a foam material incorporating wax. [Figure 3] This figure shows a schematic flowchart of a process for removing at least some of the wax additives incorporated into a foam material. [Figure 4] This figure shows a schematic flowchart illustrating the method of the present invention, which is applied to many molded materials. [Figure 5]This figure shows a schematic flowchart illustrating the method of the present invention, in which a solid additive is used to produce a molded article. [Figure 6] This figure shows schematic flowcharts relating to multiple embodiments of the method of the present invention, which includes the step of contacting a foam with an additive. [Figure 7] This diagram shows a schematic flowchart illustrating the use of a container as a mold. [Figure 8] This figure shows a schematic flowchart relating to a process using solid granules, powders, and other additives. Optionally, these can be manipulated by solids or other external stimuli. [Figure 9] This figure shows a schematic flowchart relating to a process in which the addition or removal of heat can be used to modify the properties of an additive. [Figure 10] Figure 9 shows a schematic flowchart of the ongoing process for achieving this. [Figure 11] This figure shows a schematic flowchart of the additive removal process. [Figure 12] This diagram shows a schematic flowchart of the process in which a mold is used to create indentations in the foam before CNC machining. [Figure 13] This diagram shows a schematic flowchart of the process used to create indentations in a foam before CNC machining. The diagram does not necessarily show the order of operations or any relationships between the steps on the page.

[0034] The foam is used as an example for illustrative purposes only.

[0035] Vacuum bags are intended for demonstration purposes only. Under vacuum, a vacuum bag can be placed in a suitable configuration, such as sealing a suitable sheet to a solid plate so that the sheets can come together, or as a flexible machi held between two solid plates. The plates may have one or more inlets / outlets as separate openings or valves; or as multiple openings or valves that can converge via a manifold.

[0036] The press may be mechanical or manual; or operated by hand; or a combination of the bag configurations described above, compressed mechanically or by hand.

[0037] [Detailed description of the invention] As used herein, the expression “elastic or viscoelastic” means a material. i. Deformable and elastic; or ii. This refers to a class of materials that are substantially deformable and elastic (viscoelastic) in such a way that some energy is dissipated by a process of deformation from a first position to a second position and substantially returning to the first position.

[0038] The material of the present invention comprises a matrix of a solid material having multiple voids, such as a network of voids. Examples of voids include bubbles with incomplete wall regions; tunnels; channels; holes; void plates; and void spaces. The voids may be fluid-communicated so that additives can penetrate the material through the network of voids, etc. The voids may be arranged in a series of voids, such as a honeycomb material. Such voids may or may not be fluid-communicated with one or more other voids. Nevertheless, such voids are capable of having additives added to and / or removed from them. Preferably, such voids are capable of having additives added to and / or removed from them.

[0039] Therefore, the material of the present invention is Materials that lack the ability to have additives added to them, and / or Materials that lack the ability to have additives removed from them, and / or It should be distinguished from materials that do not contain a network of voids that are fluid-connected, and which typically contain a significant number of individual gas bubbles.

[0040] For example, an open-cell foam is an elastic or viscoelastic material having a void network and can be used in the method of the present invention, while a closed-cell foam is not an elastic or viscoelastic material having a void network that can be used in the method of the present invention.

[0041] As used herein, “gap” refers to a space within a material that may be filled with, for example, a gas, liquid, or any other material other than an elastic or viscoelastic material. A gap is generally a small space, but nevertheless it can be filled with, for example, a gas, liquid, or any other material other than an elastic or viscoelastic material. Gaps may be regularly or irregularly formed. Gaps may be of the same or different dimensions. For example, in a foam, gaps generally consist of a series of spaces of different dimensions. The size of a given gap may be measured in several ways, including minimum, maximum, or average linear dimensions. It may be convenient to measure the size of a gap by average linear dimensions across two or more axes, such as two orthogonal axes. The minimum size is generally limited only by the ability of any other material other than a gas, liquid, or elastic or viscoelastic material to penetrate at least a portion of the gap(s). While there is generally no limit to the maximum size, gaps having an average linear dimension of approximately 1000 mm, for example, approximately 500 mm, for example, approximately 300 mm, for example, approximately 100 mm, for example, approximately 50 mm, for example, approximately 25 mm, for example, approximately 10 mm, for example, approximately 5 mm, for example, approximately 2 mm, for example, approximately 1 mm, are preferred. In some embodiments, the gaps are of a size of at least 0.001 mm, for example, at least 0.01 mm, for example, at least 0.1 mm. It will be understood that several techniques, such as polyurethane emulsion polymerization, may be used to form materials having multiple gaps. Such techniques generally produce materials having gaps with a size distribution. Therefore, in some embodiments, the dimensional limits described herein apply to at least 60% of the gaps, for example, at least 70% of the gaps, for example, at least 80% of the gaps, for example, at least 90% of the gaps, for example, at least 95% of the gaps. In some embodiments, the dimensional limits described herein apply to 100% of the gap.

[0042] As used herein, plural means two or more. It generally refers to cases where an elastic or viscoelastic material has at least several (3) gaps, such as many gaps, rather than just a few 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.

[0043] As used herein, “void” refers to a space within a material that may be filled with something other than an elastic or viscoelastic material, such as a gas, liquid, or any other material. Voids are generally small spaces, but nevertheless they can be filled with something other than an elastic or viscoelastic material, such as a gas, liquid, or any other material. Voids may be regularly or irregularly formed. Voids may be the same size or different sizes. For example, in a foam, voids generally consist of a series of spaces of different dimensions. The size of a given void may be measured in several ways, including minimum, maximum, or average linear dimensions. It may be convenient to measure the size of a void(s) across two or more axes, such as two orthogonal axes, by average linear dimensions. The minimum size is generally limited only by the ability of something other than an elastic or viscoelastic material, such as a gas, liquid, or any other material, to penetrate at least a portion of the void(s). While there is generally no limit to the maximum size, voids having an average linear dimension of approximately 1000 mm, e.g.

[0044] It will be understood that not all voids in the material of the present invention are necessarily in fluid communication with one another. For the purposes of the present invention, it is sufficient that 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. Thus, the term “void network,” as used herein, refers to a significant number of voids (e.g., at least 10%) that are in fluid communication with one another. Typically, at least 50% of the voids (e.g., at least 60%, at least 70%, at least 80%, at least 90%) are in fluid communication with one another.

[0045] One example of a material having multiple gaps that is functionally the same in other ways as the more expanded, networked, and voided material described above, although each gap is not necessarily an interconnected bubble, is a flexible, elongated honeycomb material that is open-cell type, but the additive does not easily (or not at all) pass from bubble to bubble. This is a common material and can be used as a substitute for regular flexible polyurethane foam. Another example may be gill-like, or resemble a soft, flexible heat sink, such that it contains many elongated members (such as plates, wings, or rods). In such examples, the material may have voids (between the elongated members), but does not contain substantial interconnections between the voids.

[0046] Other such materials of the present invention having multiple gaps may be described as having a brush-like appearance, and the material may have parallel or linear filaments (and may be retained at one or both ends). For example, a material having the appearance of a high-density silicone brush can be molded using the invention of the present disclosure. The purpose of this may be for the small-scale production of contour-formed brushes, or for prototyping or generating various vibration damping and buffering systems.

[0047] It will be understood that the present invention partially presupposes the ability of additives to penetrate into a material through gaps such as voids. Therefore, the gaps (such as voids) are limited only by the requirement that their dimensions and other properties (including the chemical and / or physical properties of the matrix surrounding the material) allow the additive to penetrate into the material through the gaps such as voids to a sufficient extent that the method of the present invention can be carried out.

[0048] Materials having multiple voids (such as a network of voids) can be formed in many ways, including by incorporating a leavening agent such as sodium bicarbonate into the material in some embodiments, so that the reagent releases gas when the material is exposed to certain conditions such as heating. Examples of such materials having multiple voids (such as a network of voids) include foams, felts, grids, scaffolding, rolled materials, meshes, and webs. Preferably, the material of the present invention is a foam, and it is convenient (for explanatory purposes only) to describe the invention in relation to foams, but it will be understood that the general principles described herein may apply to all elastic or viscoelastic materials having multiple voids (such as a network of voids). The foams may be formed, if not entirely, at least partially, from polymers, whether natural or synthetic.

[0049] It will be understood that there are many known materials that have multiple voids (such as a network of voids) that are neither elastic nor viscoelastic. Such materials include ceramic foams; 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). Such materials are not intended by the present invention for reasons discussed below, including the fact that the method of the present invention can advantageously utilize the elasticity or viscoelasticity of the material for incorporating additives. Without these properties, the incorporation and subsequent removal of additives would be more difficult to achieve.

[0050] It will be recognized that the materials should preferably be selected so as to be substantially resistant to the physical and / or chemical conditions to which they are exposed in the method of the present invention.

[0051] As used herein, the term “additive” refers to a component that is separate from the elastic or viscoelastic material and can be incorporated into at least some of the voids (such as a network of voids) within the material. Examples of additives include: Waxes or waxy compounds and mixtures thereof. The wax may preferably be water-insoluble. The waxy compounds may be water-soluble, such as PEG, panthenol, waxy emulsifiers, and mixtures thereof; 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 heating to remain liquid than, for example, pure molten sucrose; crystalline materials in a molten state that crystallize upon cooling (such as sucrose) (this example may also include one or more modifiers to lower the melting point)). Salts and sugar alcohols may be used. Euclidean mixtures of sugar alcohols with other mixtures can also be used; Electroactive materials comprising a solution containing liquid crystalline compounds (for example, electroactive liquids that self-assemble to form a more rigid material and provide some resistance, such as amphiphilic mesogens that can gel or harden in response to electrical stimulation and can be reversible if not water-soluble for removal); Non-Newtonian compounds that solidify upon machining (e.g., cornstarch and water that harden in response to applied cutting forces – such examples may also benefit from applied sonic vibrations; cornstarch and oil as electrorheological liquids that harden upon application of electrical stimulation). The advantages are the control of airborne particles and the apparent self-healing properties of some such materials that can flow into pre-cut gaps (such as voids); Granules / powder / other solids (e.g., divalent iron powder or granules (e.g., iron powder) that can flow into several materials having multiple voids (such as a network of voids), and then form a quasi-solid upon application of magnetic stimulation) (the friction between the granules and the foam essentially locks them in place). Such powders / granules can be removed in a liquid by gravity and / or sound wave oscillations, optionally combined with and / or enhanced by magnetic force). Generally, the advantage of using magnets for powders or granules is the ease with which the powder or granules can be separated from waste material; Granules / powder / other solids that can flow into several materials having multiple voids (such as a network of voids) without the influence of magnetism or other changes in conditions. For example, a foam may be fixed in a container with walls; the additive powder is agitated into the multiple voids (such as a network of voids) of the foam and any space between the foam and the walls of the container; the foam containing the powder additive is placed in a filled and supported condition so that the foam and additive can be molded in this way, and then the molded foam is agitated to remove the powder additive (after removal from the container, for example). The nominal advantages of using granules / powder / other solids that can flow into several materials having multiple voids (such as a network of voids) are: reduced energy requirements with virtually no heating required as the powder can be taken in by vibration, removed by vibration, or removed by melting if necessary; shorter processing times as the additive does not require cooling; and little to no change in size of the filled and empty foam due to the absence of thermal expansion. Granules / powder / other solids that can be subjected to changes in conditions, such as being meltable. In such examples, granules / powder / other solids can flow into several materials having multiple voids (such as a network of voids). For example, a foam may be fixed in a container with walls; additive powders are agitated into multiple voids (such as a network of voids) in the foam, as well as into any space between the foam and the walls of the container; the foam containing the powder additives is placed in a filled and supported condition so that the foam and additives can be molded in this way; before the molded foam is agitated to remove the powder additives (e.g., after it has been removed from the container), heat can be applied to the filled and supported foam to melt the granules / powder / other solids on the outer surface of the composite, making it possible to create a partial or complete seal of the granules / powder / other solids and foam composite. Similarly, the bottom surface can be melted and bonded, for example, to a work surface. The nominal advantages of using granules / powder / other solids that can flow into several materials with multiple voids (such as a network of voids) are as follows: energy requirements can be reduced by virtually eliminating the need for heating, as the powder can be taken in by vibration, removed by vibration, or, if necessary, removed by melting; processing time is shorter because the additive does not require cooling; and the size of the filled and empty foams changes little to no because there is no thermal expansion. Liquids that can be hardened or arranged and oriented to become more rigid by other means (e.g., magnetic fluids; hardens in response to a stimulus and returns to a liquid when the stimulus is gone; starch solutions that are left to dry or solidify using heat; proteins such as gelatin / collagen that are provided in solution form and then undergo intermolecular gelation).

[0052] Preferably, the additive is a wax or a waxy compound.

[0053] As used herein, the expression “wax or waxy compound” refers to a compound that solidifies, hardens, and / or stiffens sufficiently above the freezing point of water (0°C at standard atmospheric pressure, 101.325 kPa) to facilitate the execution of the methods of the present invention that enable the production of desired molded materials, but melts or softens without decomposing at temperatures above about 60°C (e.g., above about 50°C, e.g., above about 40°C). More typically, “wax or waxy compound” refers to a compound that generally solidifies, hardens, and / or stiffens above 15°C (e.g., above 20°C), but melts or softens without decomposing at temperatures above about 60°C (or above about 50°C, or above about 40°C). For example only, such a wax or waxy compound may be considered a grease-like additive that flows above 25°C, becomes almost gel-like just below 25°C, and is machinable (even if of poor quality) at any temperature below this, but improves the machinability when cooled below 0°C. An example of such a grease-like additive is a partially hydrogenated oil paste, or a substance that is gel-like at 25°C but becomes fluid above this temperature and can penetrate the foam. Such an additive remains stable in the foam at 25°C and can yield increasingly machinable results as the temperature decreases. Below 0°C, it can become as rigid as paraffin wax at 25°C. In contrast to water, such a grease-like additive is well confined in the voids of the foam above its freezing point, including a machinable temperature of 25°C.

[0054] Waxes are generally organic in nature (typically aliphatic hydrocarbons) and insoluble in water at room temperature. Waxes may wet with water and can form creams, gels, and / or pastes in some solvents, such as nonpolar organic solvents. Waxes can usually be dissolved by the addition of heat in some nonpolar organic solvents. Waxes can spontaneously emulsify in the presence of some liquids to form microemulsions and / or form emulsions containing some liquids in the presence of a surfactant(s).

[0055] Wax can have a melting point in the range of approximately 40°C to 150°C. In this sense, melting can also occur to a sufficient extent below 40°C, facilitating the incorporation of material into multiple voids (such as a network of voids). It will be understood that incorporation can be achieved even if only a portion of the wax is substantially liquid and the rest is, for example, microcrystalline.

[0056] 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 "higher viscosity" and less fluid than materials with lower viscosity. The melt viscosity of wax can range from low to high viscosity and usually depends on the molecular weight, crystallinity, and whether the wax is oxidized or copolymerized. Increasing the molecular weight and density of a wax increases its melt viscosity, while increasing its crystallinity decreases it. The fracturing ability of a wax, i.e., its affinity for particle size reduction by mechanical force, increases with increasing crystallinity and decreases with increasing density and molecular weight. The melt viscosity of wax is above its melting point and is usually low.

[0057] Suitable waxes include natural and synthetic waxes. Suitable waxes may include the following: Animal waxes (such as beeswax, Chinese wax, shellac, whale wax, and wool wax (lanolin)); Vegetable waxes and hydrogenated vegetable oils (e.g., white bayberry wax, carnauba wax, castor oil wax, esparto wax, wood wax, jojoba oil wax, aurichalle wax, rice bran wax, soybean wax, and hydrogenated oils from vegetable waxes - especially those that are paste / grease at room temperature); Mineral waxes (e.g., ceresin wax, montan wax, ozocerite wax, and peat wax); Petroleum waxes (e.g., paraffin wax and microcrystalline wax); and Synthetic waxes (e.g., polyolefin waxes including polyethylene wax and polypropylene wax, wax-grade polytetrafluoroethylene wax (wax-grade PTFE), Fischer-Tropsch wax, stearamide wax (including ethylenebis-stearamide wax), polymerized α-olefin wax, 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) and combinations thereof. Of 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 for the environmentally sustainable benefits they provide to the methods and products of the present invention. Otherwise, paraffin, microcrystalline waxes and various synthetic waxes are preferred.

[0058] Furthermore, it will be recognized that many other additives, such as sugars, sugar alcohols, salts, and iron powder, are also desirable from an environmental / sustainable / resource-recyclable standpoint.

[0059] Other examples of additives include compositions (such as colloids) containing dried ferrous iron powder or ferrous iron particles, whose properties can be oriented to stiffen foams when incorporated and modified by magnetic stimulation. Further examples of additives include non-Newtonian materials that stiffen in response to stimuli such as high-frequency mechanical waves; or liquid crystals that are placed in a stiffened state by electrical stimulation. These examples allow for the modification of the additive's properties and increase the ease of additive removal.

[0060] Specific examples of additives tested in the processes described herein include, and are listed together with their observed benefits: PEG1000-3000 - Hardness, machinability, reduction of airborne particles, melting point, water solubility PEG3000-20000 - Hardness, machinability, reduction of airborne particles, melting point, water solubility Paraffin wax - hardness, machinability, reduction of airborne particles, melting point Additives with additional qualities related to sustainability, renewable energy, and environmental impact include: Xylitol, erythritol, sorbitol; eutectic mixtures of erythritol / xylitol and erythritol / sorbitol, sorbitol / xylitol - hardness, melting point, machinability, water solubility Behentrimonium-25 methosulfate, glyceryl monostearate, stearic acid - hardness, melting point, machinability, reduction of airborne particles Sodium acetate trihydrate - hardness, melting point, machinability, water solubility Soybeans, palm oil, castor oil wax, and mixtures - hardness, melting point, machinability, and reduction of airborne particles. Isosorbide and 1,6-Hexanediol - Hardness, melting point, machinability, and reduction of airborne particles. Starch / water mixture - water-soluble, machinable, reduces airborne particles. Iron powder - hardness, machinability If the intention is to swell a material having multiple voids (such as a network of voids), such as a foam (such as polyurethane), then the following non-exclusive list of additives is preferable for machining: Trimethyl citrate, pantolactone (racemic), diacetone acrylamide, methyl nicotinate - hardness, melting point, machinability, water solubility Crotonic acid - hardness, melting point, machinability, water solubility, and precipitation from cold solutions.

[0061] As used herein, the term “contact” in the expression “contacting the material with the additive such that at least a portion of the additive is incorporated into at least a portion of the voids (such as a network of voids) in the material” means any process that brings the material and the additive into close contact such that at least a portion of the additive is incorporated in such a manner. In this context, the term “part” may mean 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 or may not be fully saturated with the additive (100% incorporation of the additive in the voids). This process may involve the use of one or more of the following: injection; immersion; agitation; vibration; use of reduced pressure (such as by applying a vacuum); or use of pressurization. Such methods may utilize a combination of such techniques.

[0062] The use of reduced pressure may involve placing the material and additives in a vacuum chamber of a fixed volume or a vacuum chamber of a variable volume (such as a bag), in which case the pressure in the chamber is subsequently reduced, thereby expanding any gas incorporated into the material, releasing it from the material and replacing it with the additive. In one embodiment, a foam material is placed in a bag, the gaseous contents of the bag are removed by vacuum, the foam is compressed, and then the foam is expanded while introducing the additive into the vacuum chamber, and / or expanding the foam to incorporate the additive. The additive can be introduced into the vacuum chamber through the same or separate ports in a manner such as by reducing the vacuum in the chamber and expanding the material (e.g., by using a peristaltic pump). This vacuum method can be particularly useful when incorporating molten wax within a foam, but generally, it is desirable to ensure incomplete saturation in such embodiments. In some embodiments, a material having multiple voids (such as a void network), e.g., foam and solid additives, is placed in a vacuum bag; vacuum is applied to the bag through an opening that compresses the material and extracts all or some of the air; the opening is then sealed, and the vacuum bag is heated to melt the additive (e.g., by placing it in a heated liquid), thereby drawing the molten additive into the material as it melts, and as the contents of the bag are returned to atmospheric pressure, a material that is fully expanded with the additive throughout is obtained. Some nominal advantages of this method include: simple equipment requiring little space, as well as less exposure to leakage and hazards; improved repeatability and consistency by measuring the weight of the additive required; and improved reliability and prevention of premature curing and sealing due to fewer pipes requiring heating.

[0063] In some embodiments, a 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 may be molded itself or consist of one or more solid components having a certain shape (e.g., two solid plates with a silicone machin or skirt fabric connecting the two; or one plate with a vacuum sheet sealed around the periphery). When a vacuum is applied, it provides planar pressure across the material, and when the vacuum is released, it provides a flat surface for the material to cool. In some cases, the bottom plate exists as an intended working surface and can be placed on a machining bed for molding. Alternatively, one or more plates can be molded (e.g., a mold). The nominal advantages are: simple equipment requiring little space, as well as less exposure to leakage and hazards; and the material (e.g., foam) remains consistently flat and square when curing. When using two plate devices for thinner sheets, warping is reduced because it can be gently sandwiched / strain limited; and / or process time and energy requirements can be reduced for specific requirements (when smaller pieces are needed, or when it is not possible to prepare larger slab material).

[0064] In some embodiments, the additive may be used to expand a material having multiple voids (such as a network of voids). For example: the material (e.g., a foam) may be brought into contact with an additive that swells the material; with the material swollen, the additive hardens; the material is molded; and then the additive is removed, and the material returns to its original size. The method offers nominal advantages. It can improve the infiltration of very fine foams by increasing the overall size of the material, and thus the flow of the additive into the material; and improves machining resolution by molding at the enlarged size.

[0065] Another variation of the use of reduced pressure is the application of force to an elastic or viscoelastic material having multiple voids (such as a network of voids) so that the material is compressed and displaces at least some of the contents of the voids from the material. When the force is released in the presence of an additive, the material expands and incorporates at least some of the additive in the material. For example, a foam can be submerged in a bath or bag of liquid wax, and the foam can be compressed to displace some of the incorporated gas, and then expanded to incorporate some of the liquid wax from the bath. In some embodiments, it is desirable to saturate the material with the additive, while in other embodiments, it is desirable to saturate the material only partially with the additive. In this embodiment, the amount of gas displaced may vary depending on the degree of compression of the material. The amount of gas present in the material can also be controlled by several techniques, including withdrawing the partially compressed material from the bath before the material has fully expanded. Another technique involves partially compressing the material so that the resulting material incorporates some of the additive and some of the gas. In further techniques, for example, the material is preferentially and unevenly immersed, for example, from one side of the material, so that the material incorporates the additive to a greater extent on one side than on other parts of the material. It has been found that by such a method, the user can produce a material that incorporates gas and wax in a desired ratio. Similar methods (maybe more) can be applied to other materials and / or additives. The ability to compress elastic or viscoelastic materials with multiple voids (such as a network of voids) will be seen as a significant departure from previous methods used for inelastic or non-viscoelastic materials.

[0066] Advantageously, the method of the present invention allows for adjustment of the amount of additive incorporated and also where the additive is incorporated within the material. For example, the additive can be concentrated in specific areas to enhance the method and / or the product. For instance, a certain amount of wax can be incorporated into the foam to an extent sufficient to simply coat the surface of the voids and fix the majority of the foam. In another embodiment, a certain amount of wax can be incorporated only into the machined layer on top of the foam, thereby substantially hardening the material and giving a higher quality surface finish. Adjusting the amount of additive incorporated into the material may allow for a reduction in the amount of additive required, thereby facilitating easier removal of the additive.

[0067] While the process of bringing materials into contact with additives has been described mostly for foams and waxes, the use of non-flowing additives is also considered. For example, additives that are granular, powdered, or mixtures thereof, especially those that are flowable, can be incorporated into materials by pouring, or, in particular, by the use of reduced pressure if the additive may be suspended in air.

[0068] As used herein, the expression "exposing the material to conditions such that at least a portion of the incorporated additives solidify, harden, and / or stiffen" means modifying the conditions experienced by the material and additives by applying one or more external stimuli. Examples of such stimuli include magnetic, electrical, thermal, chemical, mechanical, and electromagnetic.

[0069] Typically, the stimulus is a thermal stimulus, such as 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 such that the temperature of the additive (and the material incorporating the additive) decreases, and as expected, the additive solidifies, hardens and / or stiffens when the wax changes from a liquid state to a substantially solid state.

[0070] As shown above, other examples of stimulation include magnetic stimulation; application of force (including shear) by applying high-frequency mechanical waves; or application of electrical stimulation.

[0071] In some embodiments, it may be desirable to further manipulate the material before molding. Examples of manipulation may include pressing, embossing, molding, folding, joining, splicing, and / or inserting material pieces before the additives are cured or introduced. For this purpose, it may include pre-forming a shape (such as a mold), smoothing a number of joined / spliced ​​material pieces, or pressing / compressing the material to reduce the amount of additive required. For example, pre-forming or compressing a material containing additives can be used to simplify and speed up some operations. In such embodiments, for example, when replicating a shape, compression can generally be performed using a positive mold (and mirror image). For example, when producing a foam hemisphere, the mold is a positive hemisphere, and when pressed into the foam, the highest point of the hemisphere is the lowest / most compressed part of the foam, embossing a negative indentation into the foam. Therefore, the method includes the following steps: bringing a foam into contact with an additive, then placing it in a mold to compress and emboss a hemisphere in the center; the foam and additive harden in the mold; the embossing of the hemisphere is substantially lower than the rest of the foam, and therefore excluded from the cutting operation; if the foam in this case is merely a surface ground or flattened to the depths of the embossing, the resulting foam when the additive is removed will have a positive hemispherical shape that protrudes higher than the rest of the foam. In another embodiment, the method includes the following steps: stamping a single foam with a liquid additive using a positive mold; hardening the additive and maintaining the compressed or embossed state; cutting the material to remove the uncompressed portion; heating the additive and removing it to reveal a positive replica of the mold. Such a process may be advantageous for quickly creating a standard or general shape of an article before proceeding to further molding, or to easily create textures that might otherwise be a waste of time to form. This may be used as an alternative to a foam turner, but it includes removing the additive that can maintain the shape.The additional benefits are considered to be: the ability to form more complex shapes; the ability to perform further machining on the compressed foam; the fact that it is not limited to compression by rollers; the ability to maintain compressed foam slab material with a shape or texture ready for further molding at room temperature; and the ability to enable mass production of items using the original method. A further possible advantage of this is that the pre-compressed foam blank can contain, for example, the indentation of a standard wheelchair seat. Thus, one cutting path gives the basic shape, and then paths can be calculated to customize the shape for a specific customer. This effectively reduces the required cutting depth, increases the 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, a foam sheet containing a spiral emboss can be heated, and the foam will revert to a normal rectangular foam sheet. If it is cut flat along it, a spiral sheet is produced. Once the compressed shape and dimensions are known, it is still possible to mold the foam beyond the indentation shape by corrections such that the selected peaks of the spiral can be removed by machining the compressed portion. Alternatively, the rotatory trough can be removed by not machining the uncompressed portion. Overall, these processes make it possible to extend the core method of the present invention from custom fabrication to more advanced mass production, including the addition of flexibility and customization. In such embodiments, the compression process can be, for example, by compressing before cooling; partially saturating the foam, cooling it, then pressing and bonding the compressed bubbles; and using a cold press to rapidly harden portions of the foam. Alternatively, this can be done using variations of the additives described above (e.g., powders, waxes, dried powdered additives), each having its own advantages. As is evident, these processes can be paired with the core method of the present invention by using compression / embossing on one side and performing more complex machining on the other side.

[0072] Before and / or during the material molding process, the material is typically held firmly in place so that the molding device is, for example, mobile and moves around the fixed material. Advantageously, one embodiment of the present invention allows the material to be firmly fixed to a surface in such a way that the material can also be removed from the surface relatively easily upon completion of the molding process. In particular, the heated / cooled work surface can be used so as to be provided by, for example, a circulating water heat transfer. If an additive such as wax solidifies, hardens and / or stiffens as a result of a temperature decrease, the foam incorporating the additive can be fixed to the surface by situating it on a given high temperature surface (generally above the melting temperature of the wax) and then lowering the surface temperature to, for example, below the melting temperature of the wax. It has been found that the material subjected to these conditions remains fixed to the surface sufficiently to allow the molding process to take place. Upon completion of the molding process, the surface temperature can be raised, and the material can be loosened, removed and / or repositioned. Such techniques offer significant advantages over previously published processes that require the use of clamps, strong adhesives (such as super glue), which are understood to damage the material and limit the possible machinable shape dimensions.

[0073] As used herein, the expression “shaping a material” refers to any process by which a material is modified from one shape to a different shape. Generally, the present invention is best suited to subtractive shaping processes, including manual shaping and machining. Examples of machining processes include computer numerical control (CNC) machining (such as contouring machining). Such machining includes the use of lathes, mills, rotary mills, multi-axis machine arms, multi-axis water jets, lasers, thermal wires, ultrasonic knives, reciprocating blades / saws, knives, and ablation tools.

[0074] Preferably, the machining process uses examples of subtractive machining, including CNC machining, and defined tool depths or ends. Such processes having defined tool depths or ends generally include spindles (mills and rotary mills) or combinations of spindles and non-rotary feed tools (turners and rotary mills), ultrasonic tools (non-rotary cutting machines), reciprocating tools (reciprocating concentric cutting machines), concentric rotary tools, and grinding / sanding / filing / burring tools.

[0075] Such processes, which have a defined depth or end of the tool, generally do not cut at the location or radius of the guide, excluding processes such as laser, water jet, plasma cutting machines, and air jet and band saws, chainsaws and wire cutters.

[0076] As used herein, the expression “removing at least a portion” of the incorporated additives refers to the following process: The material into which the additives are incorporated is shaken (e.g., by shaking, vibrating, compressing (slow or fast; any number of compression / expansion cycles may be repeated), or by using centrifugal force) so that at least a portion of the additives are crushed and no longer incorporated, at a stage in which the additives that are not incorporated can be isolated; The material to be incorporated into the additive is placed in a liquid bath, followed by optional agitation (e.g., shaking, vibration, compression, or centrifugal force). The liquid bath may be at a different temperature than the material before being placed in the bath (e.g., a heating device). The liquid may be immiscible with the additive. In one embodiment, the additive (e.g., wax) melts, becomes unincorporated, and separates from the material. For example: The material incorporating the wax can be placed in a bath of hot water and swirled so that the wax melts, separates from the material, separates from the hot water, and accumulates on the surface of the hot water; The material incorporating the wax may also optionally incorporate a surfactant into the mixture with the wax. When placed in a bath of water (optionally warm) and agitated, the wax melts, the surfactant is solvated, and an emulsion of wax and surfactant is formed; The material into which the wax is incorporated can be placed in a bath of water (optionally warm) into which a surfactant is incorporated so that the wax (optionally melted) separates from the material and emulsifies in water; The material into which the wax is incorporated can be placed in a (optionally warm) bath of a solvent (which has the ability to solvate the wax), and the material can be agitated so that the wax (optionally melted) separates from the material and dissolves in the solvent.

[0077] The material is agitated (e.g., shaken, vibrated, compressed (slow or fast; any number of compression / expansion cycles may be repeated), or centrifugal force is used) while the material is being heated so that at least some of the incorporated additives melt and flow out of the material. For example: In one such embodiment, this process can be carried out by applying heat to the material into which the additive is incorporated so that at least a portion of the additive melts, and then compressing the material to displace most of the additive from the material; In another such embodiment, both heating and compression can be applied continuously until a desired level of additive is removed; In another such embodiment, the material may be placed in a bag, the contents of which are depressurized by vacuum, and then the bag is heated so that any additives that can be removed from the bag under vacuum melt.

[0078] It will be understood that any of the methods described above can be used to achieve partial or complete removal of additives from a material. Typically, such methods achieve partial removal of additives from the material. In such embodiments, it may be desirable to use a secondary removal process to remove any remaining additives. Such a secondary process may include one or more of the removal techniques described above. For example: Application of solvent to the material incorporating the remaining additives, optionally combined with oscillation (e.g., use of shaking, vibration, compression, or centrifugal force).

[0079] The step of removing at least some of the incorporated additives may precede a further step of recovering the surfactant, wax, and water for reuse.

[0080] In the twelfth and thirteenth embodiments, the present invention relates to a method for forming a molded elastic or viscoelastic material having a plurality of gaps (such as a network of voids), i. A step of bringing an additive into contact with a resin that can be cured in order to form an elastic or viscoelastic material in a container to form a mixture; ii. The step of degassing the mixture by vacuum or the like and / or mixing the mixture to form a homogeneous blend; iii. A step of curing the resin to form an elastic or viscoelastic material that incorporates at least a portion of the additive; iv. The step of molding the material incorporating the additive to form a molded material incorporating the additive; and v. Optionally, the step of removing at least a portion of the incorporated additive from the molded material into which the additive is incorporated. Includes, If the additive is subjected to a change under conditions selected from thermal, magnetic, electrical, chemical, and / or electromagnetic conditions, rather than water, the additive solidifies, hardens, and / or stiffens. Provide a method.

[0081] This embodiment differs from other embodiments in several respects, in that the elastic or viscoelastic material is formed from a resin that is already in contact with the additive. However, it shares some similarities. In particular, the molded elastic or viscoelastic material formed by the method may be indistinguishable from the molded elastic or viscoelastic material formed by other methods disclosed herein. The resin method may have certain advantages / disadvantages compared to the method of contacting the additive with the elastic or viscoelastic material.

[0082] The resin can be shrinkable (by heating, electromagnetic radiation, electricity, etc.), so that the foam can be molded to a larger size and then shrunk. The nominal advantages of this method include enabling the molding of microstructures that are otherwise too small to machine; and / or improving the precision of machinery – for example, when the material is finally shrunk, molding to twice the size effectively doubles the machining tolerance. This resin technique can be applied to the development of embedded molds; soft robotics; and the reproduction of very small biological structures. In the case of soft robotics, the resin can be reversibly controlled and can provide novel types of multi-cell pumps or muscle analogs. This technique can also be paired with 3D printing, thereby: an additive is 3D printed to form desired gaps (such as a void network) and coated onto the resin; and the additive and resin are 3D printed. As is obvious, this tenth aspect is fundamentally different from 3D printing of the shrinkable resin itself, as its method does not involve the use of the additive and subsequent machining steps specified herein.

[0083] In some embodiments, the additive may include a mixture that can be aerated before bead formation, has a sufficiently low vapor pressure, or can be gas-vented. In such cases, the method may include the following steps: combining the additive (such as beads) with the resin; curing the resin; placing the cured resin containing the additive, which has a sealed skin around its outside, in a vacuum chamber to produce a cured resin containing the additive in the form of a foam incorporating the additive as a space retainer; raising the temperature of the vacuum chamber and lowering the pressure so that the additive melts (in this event, in the case of an aerated additive, the trapped air expands, and therefore the bubbles in the foam expand); 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.

[0084] Many of the aforementioned processes for removing additives advantageously avoid the use of harmful solvents (compared to previously published methods), thereby reducing the solvent-related hazards, storage, and costs associated with those methods.

[0085] If solvents can be avoided, the additives and removal methods do not damage the material, thus increasing the variety of materials to which the method is suitable; however, solvent compatibility is not consistent across all materials (especially foams).

[0086] A further advantage is the ease of emulsification, especially when the additive is incorporated into a mixture with the surfactant, thereby eliminating the problem of solvent penetration when removing deeply embedded additives, which can be found in much larger articles, by using agitation in combination with the proximity of the surfactant to the additive.

[0087] The present invention offers numerous advantages over previously published methods. Previously published methods do not address the environmental impacts of those methods or disclose any progressive solutions. In contrast, the present invention enables the recovery of additives, thereby providing a progressive and environmentally sustainable method. For example, the ease of extraction and additive recovery allows for the reuse of additives, materials, and solvents (including water) in a closed-loop system. The use of additives derived from sustainable renewable resources has been found to provide improvements in environmental sustainability. A further advantage is that the present invention can be adapted in such a way as to improve storage and equipment-related adoptability, quality, time, and cost by contracting with a third party for one or more process steps. One such method may involve granting a third-party license to perform the step of incorporating additives into materials to reduce costs, improve quality, and enhance consistency. The prepared material can be delivered as needed to a third party intending to perform material molding and additive removal. The third party can then collect the additives, prepare new materials, and efficiently recycle the foam waste material. If necessary, and if required, a third party may carry out further processing or recombination of the additive. This allows smaller entities to adopt the method, and allows larger entities or newer groups specializing in the handling and compounding of additives, as well as the handling of any waste materials, to concentrate on the handling of additives.

[0088] Another adaptation that facilitates the reduction of material waste by the present invention may be the preparation of molded foam blanks for machining, such as foam seating orthotic blanks, which can be machined to specific requirements instead of being machined in large quantities from square foam blocks to achieve the same shape as the orthotic blank.

[0089] A further advantage of the present invention is the control of particulate materials (such as dust) during machining, as the additive binds to the waste material during machining, thereby effectively trapping particulate materials and thus removing most of the airborne particles, thus eliminating the need for extraction equipment.

[0090] An advantage over other methods of producing molded materials (such as foam articles) is the reduction in storage space required for mold storage, which is necessary either for large storage areas or for remaking molds from CAD files.

[0091] A further advantage is the ability to prepare materials containing incorporated additives and store the prepared materials for extended periods without requiring specific storage conditions (such as refrigeration required by some previously published methods). Thus, stockpiles of prepared materials (e.g., foams) can be made in large slabs or in predetermined sizes and shapes. Pieces can be obtained from slabs only as needed, reducing waste and increasing the economics of cutting. Furthermore, the cost of the required equipment and space can be further reduced by enabling a third party to prepare the materials and supply them to entities intending to mold the prepared materials.

[0092] The present invention may also utilize 3D model making. In a manner deviating from traditional mold making methods, the use of minimal or non-contact 3D measurement, mapping, and / or tracking can be utilized to generate data that can be manipulated using CAD / CAM methods and the resulting output in the form of machining. 3D measurement, mapping, and tracking can consist of typical medical imaging; MRI, CT, X-ray, or ultrasound, or 3D scanning, motion tracking, and mapping techniques, or pressure mapping and indentation mapping.

[0093] [Examples] The following embodiments of the present invention are not exhaustive and are provided solely for illustrative purposes.

[0094] A continuous-cell flexible foam block (2) (an example of an elastic or viscoelastic material having a void network) is prepared and molded by machining. In one embodiment, the block (2) can be saturated in a mold (4) for complete incorporation of the additive. The mold may have an open bottom (10) to allow the block to be fixed to the machine bed, or the mold may have a closed bottom (12) to allow the block to be moved and separated from the machine bed after the additive has been incorporated. In either case, the block may optionally undergo partial incorporation / removal of any additive by the use of a plunger (16). The molded product may then be removed from the mold and fixed to the machining bed (20) or separated from the machining bed (22). Once the material to which the additive (22) is incorporated has been separated from the machining bed, it may then be fixed to the machining bed by 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) can be brought into contact with wax molten at a high temperature in a bath (6) at, for example, 50-80°C, and optionally subjected to compression (14) oscillation using a plunger. The foam material is then removed from the bath, and if partial saturation is desired, excess additive (18) may be drained out. An optional secondary saturation step may be provided for one aspect (surface) of the foam material (24). In any case, the foam material may be fixed to the machined surface by a separate heating step in which a portion of the wax (26) is remelted and fixed to the machined bed. In another embodiment, the block (2) can be placed in a bag (8) into which a vacuum is applied to reduce the air in the foam, and then the high-temperature wax can be pumped in to fill the air space and uniformly saturate the foam. After the foam material is removed from the bag, the foam material may be fixed to the machined surface by a separate heating step in which a portion of the wax (26) is remelted and fixed to the machined bed.

[0095] Next, the fixed material (28) can be machined using a series of processes. In one embodiment, the material can be machined by one-sided machining (30), and the product can be removed from the machining bed by applying heat (34). In another embodiment, the material can be machined by two-sided machining (32), achieved by leaving a boundary for creating a trough. The trough (36) can be filled with wax or further wax / wax / wax (44) slurry until the top surface is at the machining level. The piece (38) can then be heated and removed from the bed (40), then rotated onto the machining surface and re-annealed (42). The rotated piece can then be machined (46) into a two-sided machining product (48) and removed from the machining bed (50).

[0096] In any embodiment, the material can be placed in a high-temperature bath of wax (52) to remelt the additive. The majority of the wax can be removed by performing removal and agitation (compression) (54). Alternatively, the molten wax may be removed from the foam material by placing the material in a bag to which vacuum and heat are applied. The finished piece (58) may be washed, or wax residue may be left to impart some degree of water repellency, conditioning and / or antimicrobial properties. Washing may be performed using a warm detergent (surfactant) solution in a bath; an ultrasonic bath using detergent and heat; continuous hot water flow or detergent use; or a warm detergent bath with agitation or compression. Alternatively, the remaining wax can be regenerated using a solvent by any of the reasonable aforementioned methods.

[0097] Figure 4 shows that the method of the present invention can be applied to many molded materials (60) as seen in step 1A, or to molded blanks (62) that are customized or machined to an acceptable degree; or to rework pre-formed materials as seen in step 1B.

[0098] Figure 5 shows an embodiment of the method of the present invention. In particular, step 1C describes an alternative process when a solid additive (64) is used to form voids in the resulting material when the additive is removed. Step 1 involves placing the solid additive (64) in a receiver (66). Step 2 involves adding the bulk elastic / viscoelastic material (68). Step 3 involves, if desired, degassing or mixing the additive and the aforementioned bulk material, and holding in the original receiver or moving to another receiver(s), followed by curing, curing, curing the bulk material. Step 4 involves molding the cured bulk material / additive mix. Step 5 involves molding or completing further molding operations to achieve the desired shape. Step 6 involves heating (70) the additive, which can be carried out in many ways with or without using a vacuum bag. Step 7 involves removing the additive by vacuum (72) and / or compression (74) means. Step 8 gives the finished article. If desired, further cleaning or processing may be initiated.

[0099] In a specific embodiment of the method, molten paraffin wax is dropped at a constant rate into a cold water bath to cool rapidly and form roughly spherical beads. The paraffin is dropped from a height sufficient to form individual droplets, but not high enough to produce irregularly shaped pieces (e.g., flat, scattered shapes). A bath with a constant annular flow keeps the paraffin beads away from the release point and minimizes bead fusion and aggregation. The paraffin beads are removed from the bath and dried. The beads are placed in a rectangular container, and a two-component curing silicone is prepared and added to the container. The container containing the uncured silicone and beads is placed in a vacuum chamber and subjected to reduced pressure to remove undesirable depressions of trapped air. The container is removed from the vacuum chamber and allowed to cure. Once cured, the silicone containing the paraffin beads can be removed from the container, resulting in a rectangular silicone block containing the incorporated paraffin beads. The rectangular block is secured to the workbench of a CNC router and machined to the desired shape. The machining process breaks the silicone outer layer, allowing for the removal of the paraffin additive. The molded piece is heated and melted, and then compressed to remove the paraffin. Detergent washing may be used to remove any undesirable residue. The final product is a molded, open-cell elastic silicone foam.

[0100] In some embodiments, the additive beads can be selected from a range of suitable materials including waxes, waxy polymers, salts, sugars, sugar alcohols, and the like. The silicone “resins” described can be substituted from a range of polymers characterized by properties such as elastic / viscoelasticity, resilience, softness, and flexibility. “Curing” in a descriptive sense can describe a range of known methods depending on the base material, such as drying, crosslinking by electromagnetic radiation, heating, or synthesis.

[0101] In addition, the additive may have secondary properties or may be manipulated in a way that alters the final product. For example, before forming the molded beads, the additive may be stirred so that the solid molded beads contain some air throughout, incorporating air into the mixture. The process then involves curing the silicone around the beads, followed by melting the paraffin beads(s) by heating the cured silicone. The heated silicone is then placed in a vacuum chamber. Vacuum is applied, causing the air bubbles dispersed throughout the additive to expand. The skin formed around the outside of the silicone prevents air from escaping from the block of silicone material, thus causing it to expand in size. The silicone piece is then cooled in its expanded state to maintain its shape. The piece is then machined, and the additive is heated and removed again, allowing the silicone piece to return to its original size. This process preferably involves the following events: The additives are blended or melted in a manner that prevents air bubbles from agglomerating and maintains an expanded state; To expand the silicone uniformly or as expected, without interference to the outer layer; The strength of the additive during expansion is sufficient to maintain the expanded state of the silicone for machining.

[0102] Figure 6 shows various embodiments of the method of the present invention, which includes the step of bringing the foam into contact with an additive.

[0103] Step 2A includes the following substeps: Substep 1 involves placing the foam (76) from Figure 4 (step 1A or 1B) into a vacuum bag (78); Substep 2 involves removing some or all of the air in order to compress the foam; Substep 3 involves introducing the additive (80) and bringing it into contact with the foam. This can be done by negative pressure of expansion or injection of the foam by other means, such as a pump, syringe or other suitable means; Substep 4 results in a foam containing the additive.

[0104] Step 2B includes the following substeps: Substep 1 involves a foam (82) located in a container containing an additive (84; for example, the additive is heated to a liquid state) and appropriate pressing (86); Substep 2 involves compressing the foam to expel all or part of the air inside; Substep 3 involves releasing the press to allow the additive to be drawn into the bubbles.

[0105] Step 2C includes the following several substeps: Substep 1 involves placing the foam (88) in a suitable vacuum bag (90) or similar container containing the solid additive (92); Substep 2 involves applying a vacuum to remove air and compressing the foam, resulting in a solid additive and compressed foam; Substep 3 involves heating the additive and foam by appropriate means, while leaving air voids or partially air voids; Substep 4 involves incorporating the additive (as it becomes liquid) into the compressed foam, resulting in an uncompressible foam containing the incorporated additive.

[0106] Figure 7 shows a similar process to that shown in step 2B, where the container acts as a mold: Step 2D includes the following several substeps: Substep 1 involves placing the foam (94) in a container (96) containing an additive (98; for example, the additive is heated to a liquid state) and a suitable press (100); Substep 2 involves compressing the foam to expel all or part of the air inside; Substep 3 involves releasing the press to draw the additive into the bubbles, followed by cooling the foam / additive within the container; Substep 4A indicates that the container or the base of the container is a workbench or floor intended to be attached to a machining bed. The sides (102) of the container may optionally be removed.

[0107] Substep 4B involves removing the cured foam (104) from the container.

[0108] Figure 8 shows a process in which solid granules, powders, etc., are additives and can be manipulated by solids or other external stimuli, either optionally or if necessary.

[0109] Step 2E includes the following substeps: Substep 1 involves applying the additive (106) as solid granules to a foam (108) located in a container that is oscillated to facilitate the movement of the additive to the foam.

[0110] Substep 2 shows the additives in the foam.

[0111] Substep 3A involves molding the foam and additives within the container to form a composite material that is substantially more solidified.

[0112] Substep 3B represents an additive that undergoes a magnetorheological change such that individual granules are held or restricted from movement substantially more firmly by a magnetic field applied near the container.

[0113] Substep 3C represents an additive that undergoes a magnetic rheological change such that individual granules are substantially more firmly held or limited by the magnetic field from movement on the workbed or machining bed.

[0114] Substep 4 shows the molded foam being agitated to remove the additive, and further assistance in attracting and collecting the additive can be enhanced by applying a magnetic field while separating the waste material from the additive. This can be carried out in a bath or elsewhere in a dry place.

[0115] Figure 9 illustrates how heat can be added or removed to modify the properties of an additive.

[0116] Step 3A includes the following substeps: Substep 1 involves cooling the additive and foam (112) by orientation; concentrating the additive (110) in a desired region of the foam by cooling substantially more of the additive in the region of interest; or by reapplying it to a desired region of the already cured foam.

[0117] In substep 2 (when the amount of additive required is reduced), the additive can be concentrated in the area that is machined to improve the molding.

[0118] In step 3B, the excess additive (114) can be drained out or compressed to the desired amount.

[0119] In step 4A, the foam can be hardened and then attached to the work surface.

[0120] In step 4B, the foam may be cured in a vacuum bag or other suitable container (including that in step 3A) and molded to form a shape.

[0121] In step 4C, the foam can be cured by other means and then retained on the work surface.

[0122] Step 5 includes the following substeps: Substep 1 involves fixing the hardened foam to the work surface by heating the work surface with or without using a heating surface for bonding the foam, or by applying a molten additive to the work surface.

[0123] Substep 2 involves cooling the workpiece surface to retain the foam, or allowing it to cool without further cooling. Alternatively, the foam can be retained by other means, such as standard workpiece holders including chucks, vises, clamps, and vacuum holders.

[0124] Figure 10 shows, as an example, how the process in Figure 9 can be continued.

[0125] Step 6A(1) involves molding the foam (116).

[0126] Step 6B describes a method for machining multiple sides, including the following substeps: Substep 1 involves applying the additive (118) to the surface or to a pre-formed and subsequently cured, molded trough.

[0127] Substep 2 involves facing a flat or molded upper surface (e.g., a pile, vise, or other mounting method such as a connecting member).

[0128] In substep 3 (for foam held in place by additives), heat the floor and change the position of the workpiece (120).

[0129] In substep 4 (if using an additive to secure the workpiece), position the workpiece and cool the workbench.

[0130] Substep 5 involves shaping the repositioned workpiece.

[0131] Substep 7 involves removing the foam, which has been molded by the application of heat, from the work surface.

[0132] Figure 11 illustrates the removal of additives.

[0133] Step 8A includes the following substeps: Substep 1 involves heating the formed foam (122) by any suitable means, for example, by conduction in a container of water or a liquid additive, or by radiant heat.

[0134] Substeps 2, 3, and 4 show the pressing of the heated and molded foam by appropriate means.

[0135] Step 8B includes the following substeps: Substep 1 shows a molded foam (124) located in a suitable vacuum bag or configuration as described in the introduction to the 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.

[0136] Substeps 2 and 3 describe the vacuum applied to remove the additive, followed by the release of the vacuum to expand the foam. Optionally, the bag can be compressed by several other means.

[0137] Further steps of washing or residue removal may be desired.

[0138] Figures 12 and 13 illustrate how heat can be added or removed to modify the properties of an additive.

[0139] Step 2F includes the following several substeps: Substep 1 involves placing the foam (126) in a container (128) containing an additive (130; for example, the additive is heated to a liquid state) and a suitable press (132); Substep 2 involves compressing the foam to expel all or part of the air inside; Substep 3 involves releasing the press to draw the additive into the bubbles; Substep 4 involves compressing the foam using mold (134); Substep 5 involves cooling the foam / additive while compressing it by the mold inside the container; Substep 6 shows the cured foam including the mold indentation; Substeps 7 and 8 involve the removal of the foam material using surface machining operations (molding); Substep 9 involves heating the molded foam by any preferred means, for example, by conduction in a container of water or liquid additive, or by radiant heat; substep 10 involves compressing the heated foam / additive; Substep 11 shows the resulting foam that reveals the shape of the mold.

[0140] Unless the context explicitly requires otherwise, throughout the description and claims, words such as “comprise” and “comprising” should be interpreted in a comprehensive sense, as opposed to an exclusive or exhaustive sense, i.e., “includes but not limited to.”

[0141] All disclosures of all applications, patents and publications cited above and below are incorporated herein by reference, if any.

[0142] Any reference to prior art in this specification should not be, and should not be, implied to be, an acknowledgment or suggestion that such prior art forms part of the common general knowledge in any field of effort in any country of the world.

[0143] The present invention can also be broadly said to be in any combination of two or more of the aforementioned parts, elements, or features, either individually or collectively, as referred to or shown in the specification of this application.

[0144] Where any integer or component having a known equivalent is referred to in the foregoing description, those integers are incorporated herein as if they were described individually.

[0145] It should be noted that various changes and modifications to the currently 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 its incidental advantages. Accordingly, such changes and modifications are intended to be included within the invention.

Claims

1. 1. A method of molding an elastic or viscoelastic material having a plurality of voids, comprising the steps of: i. providing an elastic or viscoelastic material having a plurality of voids; ii. contacting the material with an additive such that at least a portion of the additive is incorporated within at least a portion of a plurality of interstices of the material; iii. subjecting the material to conditions such that at least a portion of the incorporated additives solidify, harden and / or stiffen; iv. shaping the solidified, hardened and / or stiffened additive-incorporated material using a contour machining process to form a shaped additive-incorporated material, wherein the contour machining process is performed using CNC machining; and v. removing at least a portion of said incorporated additive from said molded material incorporating said additive. Including, The method, wherein the additive solidifies, hardens and / or stiffens at temperatures above 0°C.

2. The method of claim 1 , wherein the plurality of interstices is a network of voids.

3. The method of claim 1 , wherein the elastic or viscoelastic material is selected from foams and / or sponges, felts, lattices, skeletal structures, coiled materials, meshes and / or webs.

4. The method of claim 1 , wherein the elastic or viscoelastic material is a foam.

5. The method according to any one of claims 1 to 4, wherein the additive is selected from waxes or waxy compounds and mixtures thereof; crystalline solids / supersaturated liquids; liquid crystalline compounds; non-Newtonian compounds that solidify; granules / powders / other solids that can flow into elastic or viscoelastic materials; liquids and / or solids that can be hardened or arranged and oriented to become more rigid by other means.

6. The method according to any one of claims 1 to 5, wherein the additive is a wax or a wax-like compound.

7. 1. Use of an additive that solidifies, hardens and / or stiffens at a temperature above 0°C to mold an elastic or viscoelastic material having a plurality of voids into which the additive is incorporated, wherein the elastic or viscoelastic material is shaped by a contour machining process prior to removing at least a portion of the additive from the elastic or viscoelastic material, and wherein the contour machining process is performed using CNC machining.

8. 7. The method according to any one of claims 1 to 6, wherein the additive is selected from waxes or waxy compounds and mixtures thereof; crystalline solids / supersaturated liquids; liquid crystalline compounds; non-Newtonian compounds that solidify; granules / powders / other solids that can flow into elastic or viscoelastic materials; liquids that can be hardened or arranged and oriented to become more rigid by other means.

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