Elastic composite material

Abstract

The invention relates to an elastic composite material combined with an elastomer woven with elastic fabric that forms a non-porous reinforced material. The composite material of the invention is designed to be used in flexible systems as an imitation of human skin in any type of prosthesis or implant, preferably in functional, non-surgical penile prostheses. The composite material produced a sensory effect similar to human skin in appearance and functionality and is resistant to stress, preventing tearing-related issues.

Description

[0001] DESCRIPTION Elastic composite material. TECHNICAL FIELD The present invention relates to an elastic composite material for use in flexible, cushioning, containment or protection systems in fields such as cinema (special effects) or the plastic arts, science and medicine (as laboratory material), automotive, scuba diving, hydraulics or pneumatics, among others; although its preferred use and for which it has been designed is the imitation of human skin in functional (autonomously erectable) and non-surgical penile prostheses. To this end, the material of the invention is configured from a combination of an elastic fabric combined with an elastomer, preferably silicone. BACKGROUND OF THE INVENTION Non-erectile prostheses that use elastomers (mainly silicone) to manufacture the membrane that emulates the skin are known.However, since these are non-functional prostheses, they only emulate the appearance of the prosthetic, neglecting mechanical performance. Therefore, when using the membranes of these prostheses in functional prostheses, problems of stress fractures or the ease with which the elastomer's fracture limit is reached quickly arise. Furthermore, if, to solve this problem, their thickness or Shore is increased to a value that is safe against fracture, their appearance and feel are far removed from those of real skin. The applicant for this utility model is not aware of any stress-resistant materials in the state of the art that can accurately emulate the behavior and produce a sensory effect similar to human skin in appearance and functionality.For this reason, the object of the present invention proposes an elastic composite material that precisely meets the objective pursued and that, advantageously, allows its preferential use as synthetic skin in all types of prostheses and implants, among other applications. DESCRIPTION OF THE INVENTION The present invention makes it possible to solve the aforementioned problem, offering a composite and elastic material in the form of skin, of variable thickness, which has the dynamic properties necessary for its use in a functional prosthesis. It should be noted that the material of the present invention, during its use in a functional prosthesis, is subjected to pressure, stretching and friction, so the mechanical, elastic and stress resistance performance of the elastic composite material in the form of skin are highly relevant.To meet these requirements without losing the resemblance (in aesthetics and performance) to real leather, the elastic composite material of the invention comprises an elastomer woven with an elastic fabric, the whole defining a non-porous reinforced material. Preferably, the elastomer is a silicone, such as a curing silicone, preferably a platinum-catalyzed silicone. Thus, the properties provided by the weaving are crucial to achieving a durable, resistant, and lifelike leather. The elastic fabric used for the weaving is preferably what is commonly known as Lycra (which in turn can have different components: nylon, polyamide, elastane, polyurethane elastic fibers, etc.).In this way, the elements: the elastomer (preferably silicone) and the elastic fabric (preferably Lycra) that form the elastic composite material give it mechanical characteristics and tolerance to stress and tearing superior to those of a synthetic leather made solely with silicone. Preferably, the silicone in the elastic composite material is a Shore 0010 to 0030 curing silicone encapsulated by a Shore 2 silicone, while the elastic fabric is preferably Lycra with an elongation to break of between 300% and 620%. Lycra should be understood as the elastic material formed by a percentage of elastane, which normally ranges between 5% and 20%, in addition to other components, which are usually polyamide and / or polyester.Thus, the elastic composite material of the present invention offers a low thickness that emulates thin skin, with a preferred thickness between 0.75 and 3 mm depending on the requirements pursued in the area where it is to be implemented. Advantageously, the present elastic composite material changes color saturation and transparency as it changes state during stretching, due to the characteristics of the material it is made of, which contributes to its realism as skin and to that of the prosthesis as a whole. Furthermore, the weaving of the elastomer with elastic fabric is preferably made from lycra with a thread concentration of between 30x15 threads / cm. 2 and 90x45 threads / cm 2, such that the elastic composite material has a thickness between 0.75 mm and 3 mm with a breaking limit of at least 2.65 kg / cm. Finally, it should be noted that, in a preferred application of the invention, the elastic composite material covers and externally envelops the set of elements of a functional prosthesis (for example, its pneumatic erectile system), offering in use a behavior and sensory effect similar to human skin in appearance and functionality throughout the entire erectile process.In short, the elastic composite material developed and object of the present invention offers the user of a functional prosthesis a response that resembles that of real skin in terms of touch and manipulation from the state of rest to that of total erection. PREFERRED EMBODIMENT OF THE INVENTION During the development of the present invention, specifications were established as an objective in terms of appearance and functionality of a material to be developed in order to obtain a synthetic skin made with elastomers and intended to cover the elements that make up a prosthesis. The development of a material made with elastomers that emulates human skin, both in mechanical and sensory behavior, has required the introduction of an element that, added to the elastomer, transforms it, improving its mechanical and sensory response in thicknesses similar to that of real skin. This involves adding an elastic fabric that reinforces the silicone.Among the different elastomers, platinum-curing silicones were ultimately chosen, cutting-edge elastomers that offer almost tailor-made performance. Furthermore, these curing silicones are hypoallergenic and medical-grade. The choice of elastic fabrics to be used was determined by their strength, thickness, lightness, and weave, with Lycra being the optimal choice, which is commercially available in combination with other materials, for example, nylon, elastane, polyamide, etc. During the development of the invention, it was found that materials composed solely of silicone (due to the characteristics of silicones), and choosing thicknesses that could be used to create simulated skin, did not yield satisfactory results in terms of handling. Silicone's poor resistance to stretching and stress leads to breakage and deformation.In terms of sensory response, silicone alone is far from resembling skin, as it stretches excessively (as an elastomer), a phenomenon that does not occur in real skin. Following these observations, tests were conducted to find an element or process that would improve the characteristics of silicone, as well as a way to implement non-elastic fabrics. After successfully weaving (i.e., assembling) the silicone by incorporating elastic fabrics into its production, an elastic composite material was obtained that met the established needs. Thus, the elastic composite material is a woven, non-porous membrane made with two components: silicone + elastic fabric (Lycra). It was found that the developed material improved the performance of silicones, being a material that resists stress at thin thicknesses, while simultaneously improving its mechanical and sensory performance, eliminating excessive elasticity.In the tests, samples were prepared, choosing elastic fabrics based on their composition (cotton, polyester, silk, and blended fabrics), thickness, and weave. Silicone was applied to the samples in two ways: by injection or by manual application (depending on viscosity). The observations drawn from these tests are listed below: - Some of the samples (fabrics with rubber or latex) inhibited certain silicones. We ruled out all elastics with rubber or latex. - With very dense weaves (regardless of thread thickness), the silicone does not blend with the fabric, remaining as an overlying layer. Therefore, the fabrics cannot be too tightly woven to ensure the silicone is integrated into the weave. - In very open weaves, the threads, when separated, become strips and can cut the silicone.The results of these tests determined that Lycra was the appropriate fabric to achieve the established objectives. Once the two materials to choose from were determined, specific tests were conducted with the elastic composite material of the present invention. In this sense, elongation to break, Shore hardness, viscosity, tensile strength, and recovery speed are basic parameters that define the excellent properties of curing silicones, but so is puncture or cut resistance, and in this regard, these silicones show very low values. This deficiency is decisive in thinner thicknesses, where the absolute tensile strength also decreases, making it much easier to reach the breaking point. Thus, in the development of the present invention, the silicone was woven with Lycra to optimize its elastic response.The aim is, on the one hand, to reduce its elongation capacity by increasing its tensile strength, making it more difficult to reach the breaking point; and, on the other, to improve its response to sizing, cutting, and puncture. A Lycra composed of polyamide and elastane, specifically 90% polyamide and 10% elastane, and a Shore 0020 silicone encapsulated by a layer of Shore 2 silicone, were chosen. Different samples were prepared: Lycra alone, silicone alone, and silicone woven with Lycra. Sizing and puncture tests were also performed. The results obtained from these tests were as follows: - The weight / elongation ratio varied, confirming that the silicone samples required less weight than the Lycra samples (and the latter less than the elastic composite material of the present invention) to achieve the same elongation. - Silicone alone showed greater elongation to break.- The elongation to break of the Lycra and the elastic composite material of the present invention were similar, but lower than that of silicone alone, and they also presented much greater resistance to stretching. Another fact worth noting is that although both Lycra and the elastic composite material of the invention have almost the same elongation to break, the force required to reach that point in the material developed by the present invention is approximately 15% to 25% greater. Therefore, more force is required to stretch the material of the present invention than to stretch the Lycra and, of course, than to stretch the silicone alone. In other words, with the developed material, we limit elasticity and increase force; in other words, it is more difficult to reach the breaking point.- It was also found that, when cut and punctured, the elastic composite material of the present invention, because the silicone is reinforced with Lycra, considerably hinders the cut or puncture from enlarging, eventually causing it to tear completely. - The elongation to break and the tensile force of the elastic composite material of the present invention are determined by the Lycra and its tensile moment when the silicone is injected. That is, it is a controllable process that allows for gradation. In addition, it allows for the control of the appearance of wrinkles on the surface, bringing us closer to the natural appearance of skin. - The shore of the silicone used in its composition is maintained in the elastic composite material of the present invention.With these conclusions, it is clear that the elastic composite material of the present invention is ideal for the production of simulated skin that must withstand stretching, bending, and pressure with minimal thicknesses, thereby achieving mechanical behavior more similar to that of skin by establishing a limit to the elongation that silicone alone can undergo. This limit is also difficult to achieve, since the reinforcement with Lycra offers resistance to stretching, providing greater recovery and thus avoiding the elastic sensation typical of elastomers, a sensation that cannot be appreciated in the behavior of real skin. The tests performed are described and shown below, in which the elongation and damage suffered (as a function of the force applied) of three materials were tested: Lycra, silicone, and the elastic composite material of the present invention.The tests were carried out as follows: closed circular strips of each material were made (from strips of identical width and length), and the elongation and damage suffered by the material were observed and measured as a function of the stretch to which they were subjected. The results tables for each of the materials mentioned are shown below.

[0002] Lycra results table: Tension at which damage to material begins to Tension to break (kP) Elongation at break (%) Test 1 3 13 611 Test 2 2.5 12 588 Test 3 2 11 573 Test 4 2 13 604 Test 5 4 11 575 Test 6 2 11 569 Test 7 1.5 12 590 Test 8 3.5 11 581 Test 9 2 13 598 Test 10 2 11 575 Silicone results table (tapes thickness 2.5 mm): Tension at which damage to material begins to Tension to break (kP) Elongation at break (%) Test 1 4 5 853 Test 2 4.5 4.5 848 Test 3 3.5 3.5 840 Test 4 3.5 4 845 Test 5 3 3 838 Test 6 3 4 841 Test 7 4 5.5 858 Test 8 3.5 4 843 Test 9 3.5 4.5 846 Test 10 4 4 841 Table of results of the elastic composite material of the present invention (Lycra with 90% polyamide and 10% elastane, and shore 0020 silicone encapsulated by a layer of shore 2 silicone) (thickness of tapes of 2.5 mm): Stress at which damage to the material begins to be Stress at break Elongation to break (kP) observed (kP) Test 1 9 13 582 Test 2 6 14 590 Test 3 7 12 577 Test 4 7 13 576 Test 5 9 14 583 Test 6 8 14 592 Test 7 8 15 601 Test 8 7 14 589 Test 9 9 15 594 Test 10 10 14 581,

Claims

MODIFIED CLAIMS received by the International Bureau on August 8, 2025 (08.08.2025) 1. Elastic composite material characterized in that it comprises an elastomer woven with an elastic fabric defining a non-porous reinforced material, where the elastomer is 5 is encapsulated by another elastomer of higher shore.

2. Elastic composite material, according to claim 1, characterized in that the elastomer is a silicone. 10 3. Elastic composite material, according to claim 2, characterized in that the silicone is a curing silicone.

4. Elastic composite material, according to claim 3, characterized in that the curing silicone is a platinum curing silicone. 15 5. Elastic composite material, according to claim 1, characterized in that the elastic fabric is lycra.

6. Elastic composite material, according to claim 3, characterized in that the silicone of 20 cured is a shore silicone between 0010 and 0030 encapsulated by a shore 2 silicone.

7. Elastic composite material, according to claim 5, characterized in that the elastic fabric is a lycra with an elongation to break between 300% and 620%. 25 8. Elastic composite material, according to claim 5, characterized in that the elastic fabric is a lycra with a thread concentration between 30x15 threads / cm 2 and 90x45 threads / cm 2 9. Elastic composite material, according to claim 1, characterized in that it has a thickness between 0.75 and 3 mm. 30