Device for holding coral slices and support structure

Abstract

The present invention relates to a device for holding coral slices, the device comprising: a first hollow tubular element extending along a longitudinal axis and having a distal end, a proximal end, an inner surface, and an outer surface; and a second element disposed coaxially with the proximal end of the first element and having a flared portion defining a flat surface constituting a surface extending circumferentially about the longitudinal axis of the first element, wherein the device has a textured surface.

Description

[Technical field]

[0001] The present invention relates to devices for holding fragments or pieces of aquatic animals, particularly corals, for the cultivation and growth of these animals, and to supporting structures for such devices. These devices and structures may be used in aquariums to allow the growth of corals from the fragments, but may also be used in marine environments.

[0002] The invention also relates to methods of making these devices and support structures, and to the use of biodegradable polymers to make these devices and support structures. [Background technology]

[0003] Corals are a diverse group of sea anemone-like animals that live in marine environments. Corals include soft corals, hard corals, sponges, sea fans, etc. Hard corals, which are animals of the phylum Cnidaria, are composed of several individuals, or polyps, that share a common skeleton made essentially of calcium carbonate. These polyps and their skeletons form colonies.

[0004] Many types of coral can be grown asexually by propagation from fragments or sections. For example, a piece of live coral can be broken off into several smaller pieces or fragments. The fragments are then attached to a substrate or support. After cutting off a fragment of the colony, the living tissue of this fragment, or section, consisting of the polyps, recovers and resumes its growth, producing a skeleton and new polyps, thereby creating a new colony. Harvesting coral fragments allows, among other things, transplanting the fragments onto reefs to aid their natural regeneration, avoiding the removal of corals from their natural environment for sale to aquatic life enthusiasts, growing corals in laboratories for scientific study and public display, and collecting endangered species.

[0005] It is important to attach the coral fragments to a substrate or support early in propagation so that the coral can grow properly. If the coral is not properly attached to the substrate, the fragments may tilt or move and the natural attachment of the coral to the substrate may be delayed or not occur, resulting in stunted growth.

[0006] Currently, the most common method for harvesting sections from coral colonies after cutting the fragments is to adhesively bond the sections to a plastic or concrete device using a permanent fixation product. Depending on the location of the section, the device can itself be attached using the same adhesive to a support placed in the destination environment, i.e. an aquarium or a submarine reef.

[0007] The calcareous nature of the coral skeleton requires the use of adhesives such as epoxy resins (polyepoxides), cyanoacrylates, or adhesive mortars, which have the disadvantage of being somewhat toxic to the corals and aquatic fauna in general.

[0008] Epoxy resins in paste form are often used to glue coral sections because they are water resistant and can be handled in a marine environment. However, these adhesives are highly sensitizing and are recognized as the cause of most allergic eczema occurring in the context of occupational activities. Furthermore, the base components before polymerization can release esters derived from phthalic acid and various alcohols that are toxic and harmful to coral growth.

[0009] Cyanoacrylates allow various materials to be rapidly bonded together, however, in addition to their toxicity issues, they also have the disadvantages of having a short shelf life and curing upon contact with water or even ambient moisture, the latter making them difficult, if not impossible, adhesives to use in the field.

[0010] Adhesive mortars generally consist of a mixture of air lime and cement. They are widely used in construction work. These adhesives are very sensitive to changes in storage conditions and are therefore difficult to store for long periods of time. These products carry the risk of lung damage after prolonged inhalation. In addition, they produce an alkaline reaction in the presence of water, which can cause severe irritation in case of contact with the eyes or skin. This alkaline reaction can also lead to a weakening of the structures in which these agents are used, thus affecting the durability of bonds in contact with seawater.

[0011] In some cases, the sections adhesively bonded to the holding device are then attached to the reef using metal nails and / or plastic tie straps. Again, these methods are potentially damaging and / or toxic to the coral.

[0012] As an alternative to methods involving adhesively bonding the segments to a holding device, there are devices that allow the segments to be held without adhesive bonding by fastening them to a ring or bulb, such as the "Frag Gripper by Reef Stew - the No Glue Frag Mounting System" sold by Vivid Creative Aquatics (vividcreativeaquatics.com / shop / frag-gripper-by-reef-stew / ). However, this holding device must be adhesively bonded to the support or to the rod that is intended to be inserted into the support. Such devices are suitable for branching corals, but not for blocky corals.

[0013] The supports to which the sections are usually adhesively bonded or attached, made for example of plastic or concrete, may also pose toxicity risks, exacerbate damage factors for coral reefs, or even have negative environmental impacts due to the way they are made.

[0014] For example, plastic materials, such as polyethylene terephthalate or polyvinyl chloride, can release endocrine disrupting substances, such as antimony trioxide or phthalates. It has been observed that in areas polluted by plastic, corals are more susceptible to disease. Contact between plastic particles and corals can cause damage to the coral tissue, thereby promoting infection by bacteria. Furthermore, certain additives present in plastics attract coral polyps and promote their ingestion of plastic, increasing the risk of transmitting toxic elements to the coral polyps while keeping them away from real food necessary for their growth and survival.

[0015] Concrete, composed primarily of water, cement, and sand, is used in construction projects all over the world. Sand often comes from the seabed or shorelines, and its removal causes mechanical damage to reefs. Cement production produces some of the highest levels of CO2 emissions in the world. 2 and CO 2 is a major contributor to global warming, resulting in the destruction or even disappearance of coral reefs. Summary of the Invention [Problem to be solved by the invention]

[0016] It may be advantageous to have a device for holding coral slices or fragments that does not require an adhesive bonding step, either to attach the slice or fragment to the holding device or to attach the device to a support structure.

[0017] There is also a need to have a device for holding coral slices or fragments, or a support structure for such a device, that can be readily made from materials that are biodegradable, biocompatible with coral, and non-toxic to the environment.

[0018] There is also a need to have a device for holding coral slices or fragments, or a support structure for such a device, whose biomimicry encourages coral growth and proliferation.

[0019] There is also a need to have a device for holding coral slices or fragments, or a support structure for such a device, whose surface texture is rough in a manner that encourages coral growth and proliferation.

[0020] There is a need to have a device for holding coral slices or fragments, or a support structure for such a device, whose surfaces are textured to exhibit roughness that can create a frictional effect when the surfaces contact and aid in holding the device within the support structure, without the use of adhesive bonds.

[0021] There is also a need to have a device for holding coral slices or fragments that may be suitable for holding any type of coral slice or fragment, whether branched or chunked, of various sizes.

[0022] There is also a need to have a device for holding coral slices or fragments, or a support structure for such a device, that can be produced in a simple manner by 3D printing or molding, especially by 3D printing.

[0023] There is also a need to have a device for holding coral slices or fragments, or a support structure for such a device, that allows for replicating as closely as possible the natural growth of coral in situ.

[0024] There is also a need to have a device for holding coral slices or fragments, or a support structure for such a device, that does not have, or whose use does not produce or require, agents that are potentially toxic to the environment or to corals.

[0025] There is also a need to have a device for holding coral slices or fragments, or a support structure for such a device, that requires minimal handling to ensure that the slices are held within the device and that the device is attached to the support structure.

[0026] There is also a need to have a device for holding coral slices or fragments, or a support structure for such a device, that can be used in an aquarium or on the seabed.

[0027] There is also a need to have a device for holding coral slices or fragments that can be attached to natural reefs without the use of adhesive bonds.

[0028] There is also a need to have a support structure that allows the internal structure to be filled and ballasted with water.

[0029] The present invention aims to meet these various needs, either completely or in part. [Means for solving the problem]

[0030] According to one of these first subjects, the invention relates to a device for holding coral pieces, the device comprising: a first hollow tubular element extending along a longitudinal axis and having a distal end, a proximal end, an inner surface, and an outer surface; and a second element disposed coaxially with the proximal end of the first element and including a flared portion defining a surface that extends circumferentially about the longitudinal axis of the first element; Equipped with wherein the device has a textured surface. Regarding the above device.

[0031] According to one embodiment, the device has a textured surface on the inner side.

[0032] According to one embodiment, the flared portion may comprise an edge which together with the flat surface defines a flange about the longitudinal axis, the flange being advantageously deformable in a direction substantially parallel to the longitudinal axis of the tubular member.

[0033] According to one embodiment, the surface constituting the surface extending in the circumferential direction about the longitudinal axis may comprise at least four elongate projections, each projection having a distal end, which projections are arranged in the plane of the surface of the flared portion and extend in a circular arc in the direction of the longitudinal axis of the hollow tubular element together with the flared portion in such a way as to form a retaining member together with all the distal ends located around the longitudinal axis. In particular, the surface constituting the surface extending in the circumferential direction about the longitudinal axis may comprise at least 5 to at least 15, in particular at least 7 to at least 12, in particular at least 10, elongate members.

[0034] The inventors have surprisingly discovered that it is possible to create a device for holding coral slices or fragments that is configured such that the coral fragments can be held within the device without the use of adhesive bonds, and such that the device can be placed and attached to a support in an aquarium or on the sea floor without the use of adhesive bonds.

[0035] The inventors have also discovered that biodegradable polymers, such as lactic acid polymers, containing calcium salts, such as calcium carbonate, can be used to create devices for holding coral slices or fragments, or support structures for such devices.

[0036] The inventors have also discovered that devices for holding coral slices or fragments, or support structures for such devices, can be fabricated by three dimensional printing techniques to allow for the provision of a textured surface on the device or support structure.

[0037] The textured surface on the holding device or support structure advantageously allows for biomimicry to be created to encourage growth and proliferation of the coral. The textured surfaces also advantageously have a roughness that allows for a frictional effect when in contact with one another in a manner that promotes retention and attachment of the device within the support structure without adhesive bonds.

[0038] The biodegradability of the materials used advantageously allows the retention device and the support structure to be well integrated into the natural environment while minimizing possible negative effects.

[0039] The inventors have unexpectedly discovered that it is possible to create a device for holding coral slices or fragments by providing the device with a shape that allows for both attaching and holding the coral slice, and for inserting and attaching it to a supporting structure or natural reef, all without the use of adhesive bonds. In particular, the design of the holding device allows for the coral slice to be held within the device by being compressed by one or more portions of the device in contact with the slice.

[0040] Fabrication of the devices and support structures of the present invention by 3D printing advantageously allows for a manufacturing method that is simple, low cost, and easily adaptable to the various dimensions of the coral slices.

[0041] The inventors have surprisingly discovered that the biodegradable materials used and the method of manufacture by 3D printing make it possible to ensure the flexibility of the holding device, endowing it with the property of holding the coral slice within the device by compression of the slice by one or more parts of the body of the device that are in contact with the slice.

[0042] The inventors have surprisingly discovered that the biodegradable materials used and the method of manufacture by 3D printing make it possible to impart texture, or roughness, to the surfaces of the devices and support structures described herein in a simple and low-cost manner.

[0043] One of the advantages of the present invention is that it provides a device for holding coral sections, and a support structure for such a device, that allows for holding coral fragments without the use of adhesive bonds.

[0044] Another of the advantages of the present invention is to provide a device for holding coral slices, and a support structure for such a device, that has biomimetic properties that encourage growth of the coral.

[0045] The devices described herein can advantageously be placed and attached to any suitable support within the aquarium or natural hole in the undersea reef, in particular the support structures described herein, without the need for the use of a binder.

[0046] In accordance with another of the advantages of the present invention, the devices and support structures described herein may be implemented using biodegradable materials that do not contain any elements that are toxic to the coral or its environment.

[0047] According to another of its advantages, the devices and support structures of the present invention may be manufactured by 3D printing, which may make it easy to adapt their dimensions to the various dimensions of the coral fragments.

[0048] According to one embodiment, the first element may include at least one spike extending from the inner surface towards the inside of the element.

[0049] According to one embodiment, the textured surface of the device may have a surface roughness that allows it to generate friction with the surface of the coral slice and / or with the contact points of a support structure. In particular, the textured surface may have an average surface roughness of at least 0.5 μm, in particular an average surface roughness in the range of 0.5 μm to 320 μm.

[0050] According to one embodiment, the device according to the invention may be formed from a material comprising at least one biodegradable polymer and at least one calcium salt.

[0051] The biodegradable polymer may be selected from polylactic acid polymers, glycolic acid polymers, polyhydroxyalkanoates, poly(alkylene succinic acids), polycaprolactones, polytrimethylene terephthalates (PTT), and combinations thereof. In particular, the biodegradable polymer may be a lactic acid polymer.

[0052] The calcium salt may be an organic calcium salt. The organic calcium salt may be selected from calcium carbonate, calcium citrate, hydroxyapatite, calcium lysinate, calcium alginate, and combinations thereof. In particular, the calcium salt may be calcium carbonate.

[0053] According to one embodiment, the device according to the invention may comprise a coral piece.

[0054] According to another of its subjects, the present invention relates to a support structure for at least one device according to the invention, said support structure comprising a continuous surface with at least one hole configured to receive a hollow tubular element of a device according to the invention, wherein said surface is a textured surface.

[0055] According to one embodiment, the structure may have an interior comprised of a plurality of cells, the plurality of cells communicating with each other and with the aperture, directly or indirectly.

[0056] According to one embodiment, the structure according to the invention may be formed from a material comprising at least one biodegradable polymer and at least one calcium salt.

[0057] According to one embodiment, the textured surface of the structure may have a surface roughness that allows it to generate friction with the device of the invention. In particular, the textured surface may have an average surface roughness of at least 0.5 μm, in particular an average surface roughness in the range of 0.5 μm to 770 μm.

[0058] According to one embodiment, the support structure may comprise at least one device according to the invention.

[0059] According to one embodiment, the support structure may comprise at least one device according to the invention inserted into a hole, the device comprising a flange, wherein the flange is fixed to the surface of the structure.

[0060] According to another of its subjects, the present invention relates to a method for manufacturing a device for holding coral slices according to the invention or a support structure according to the invention, comprising at least one step consisting of 3D printing said device or said structure.

[0061] According to one embodiment, the printing material used in the method of the present invention may be a biodegradable polymer that includes a calcium salt.

[0062] According to another of its subjects, the present invention relates to the use of a biodegradable polymer comprising at least one calcium salt for manufacturing a device for holding coral slices according to the invention or a support structure according to the invention. [Brief description of the drawings]

[0063] [Figure 1]FIG. 1 shows a device for holding coral fragments or pieces having a flared top defining a flange. [Diagram 2] FIG. 2 shows a cross section through the device according to FIG. [Diagram 3] FIG. 3 shows a device for holding coral fragments or sections that includes a flared top having elongated projections that define holding members. [Figure 4] FIG. 4 shows a cross section through the device according to FIG. [Diagram 5] FIG. 5 shows a device according to FIG. 3 with fragments of massive coral. [Figure 6] FIG. 6 shows a device according to FIG. 1 with a fragment of branching coral. [Figure 7] FIG. 7 shows a device according to FIG. 1 installed in a hole in a support structure with the flange raised. [Figure 8] FIG. 8 shows a device according to FIG. 1 installed in a hole in a support structure with the flange fixed to a surface of the support structure. [Figure 9] FIG. 9 shows a holding device according to FIG. 3 installed in a holding device according to FIG. [Figure 10] FIG. 10 shows a modification of FIG. [Figure 11] FIG. 11 shows a cross section through a device according to FIG. 1 with spikes arranged on the inner surface of the hollow tubular element and on the upper surface of the second element. [Figure 12] FIG. 12 shows a suitable support structure for the device of the present invention. [Figure 13] FIG. 13 shows a cross section of FIG. 12 revealing the honeycomb interior. [Figure 14] FIG. 14 shows a cross section through a support structure according to FIG. 12, with devices according to FIGS. 1 and 3 each equipped with coral fragments provided in some of its holes. [Figure 15]FIG. 15 illustrates a possible use of the retention device according to the invention, either placed on a support structure installed in an aquarium or placed on a natural reef present on the ocean floor. [Figure 16] FIG. 16 shows the principle of 3D printing by superposition of layers of polymer extruded from a printing nozzle. [Figure 17] FIG. 17 illustrates the variability of the average surface roughness as a function of the thickness of the layer of the polymer extruded from a printing nozzle. [Figure 18] FIG. 18 illustrates 3D printing of the device according to FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0064] definition It should be noted that as used in this specification and the appended claims, the singular forms "a" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a device" includes reference to a plurality of devices, reference to "a structure" includes reference to a plurality of structures, etc.

[0065] The phrase "comprising a" should be understood to be synonymous with "comprising at least one."

[0066] The words "around" or "approximately" as used herein in connection with a numerical value or parameter refer to the normal error interval known to one of ordinary skill in the art for the measurement of that value or parameter. Reference to a "value or parameter" "around" encompasses and describes embodiments that use that value or parameter. In some embodiments, the word "around" refers to ±10% of a given value. However, when the value in question refers to an indivisible object that loses its essence when further divided, "around" refers to ±1 of that indivisible object.

[0067] The aspects and embodiments of the invention described herein include variations of those aspects and embodiments "having," "comprising," "consisting of," and "consisting essentially of." The words "have" and "comprise," as well as variations such as "has," "having," "comprises," or "comprising," used in connection with an element, are understood to imply the inclusion of one or more of the elements referenced without the exclusion of other elements. The word "consisting of" implies the inclusion of the elements set forth to the exclusion of additional elements. The word "consisting essentially of" implies the inclusion of the elements stated and possibly other elements, where those other elements do not materially affect one or more basic characteristics of the disclosure. Various embodiments of the present disclosure using the word "comprising" or equivalent words are understood to include embodiments in which the word is replaced with "consisting of" or "consisting essentially of."

[0068] In the description, the term "essentially" or "substantially" used in connection with a feature is intended to define a set of variants of the feature that are roughly similar, but not completely similar to the feature. The difference between a given feature and a set of variants is such that the properties and functions of the feature are not substantially affected in all embodiments corresponding to the set of variants of the given feature. For example, the term "substantially" referring to a position, such as "substantially parallel", is used to describe a set of positions that are close to, but not exactly the same as, a parallel position.

[0069] It will be appreciated that certain features of the invention that are, for clarity, described in the context of separate embodiments, can also be combined in a single embodiment. Conversely, different features of the invention that are, for clarity, described in the context of a single embodiment, can also be implemented separately or in any suitable subcombination.

[0070] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art of the present invention. All methods and materials similar or equivalent to those described herein may also be used in the practice of the present invention. All documents mentioned herein are incorporated by reference to describe the methods and / or materials in connection with which such documents are cited.

[0071] The lists of sources, ingredients, and components set forth below are intended to include in any combination or mixture thereof, and are recited herein for inclusion in any given list. Such lists may be read and interpreted to mean "selected from the group consisting of" and "combinations thereof" of the given list of compounds or items.

[0072] Each maximum numerical limitation given in the description includes every lower numerical limitation, as if such lower numerical limitations were expressly written herein. Each minimum numerical limitation given in the description includes every higher numerical limitation, as if such higher numerical limitations were expressly written herein. Each numerical range given in the description includes each narrower numerical range subsumed within the given numerical range, as if those numerical ranges were expressly written herein.

[0073] In the detailed description of the invention, reference is made to certain materials, compounds, or devices having specific trade names, and the invention is not limited to the use of those specific materials, compounds, or devices, but includes any equivalents known in the art.

[0074] Holding Device The holding device (1, 21) according to the invention for holding coral pieces comprises: a first hollow tubular element (2) extending along a longitudinal axis and having a distal end (3), a proximal end (4), an inner surface (13), and an outer surface (5); a second element (6) disposed coaxially with the proximal end of the first element and including a flared portion (7) defining a flat surface (10) that constitutes a surface extending circumferentially about the longitudinal axis of the first element (2); may comprise at least Here, the device has a textured surface (8).

[0075] The first element has a body (9) between its distal end (3) and proximal end (4) defined by the inner surface (13) and the outer surface (5) of the first element.

[0076] The second element (6) of the device of the invention may comprise a flared portion with an edge (11) that together with the flat surface (10) of the flared portion (7) defines a flange (12) about the longitudinal axis. The flange (12) may be an integral piece and may form a continuous surface constituting a surface extending circumferentially about the longitudinal axis of the first element. Alternatively, according to one embodiment not shown, the flange (12) may have a break disposed substantially perpendicular to its edge. The break may take the form of a cut or notch extending from the edge of the flange to the proximal end of the first element.

[0077] The flange (12) may be deformable in a direction substantially parallel to the longitudinal axis of the first element (2). Advantageously, the flange (12) may be deformable in the direction of the distal end (3) of the first element (2). Thus, when placed on a support, for example a support structure as defined below or a natural reef on the seabed, the deformable flange (12) may be folded downwards towards the distal end (3) of the first element and become fixed to the surface of the support. By becoming fixed to the surface of the support, the flange promotes attachment and retention of the device to the support through frictional forces generated by its textured surface.

[0078] According to one embodiment shown in Fig. 1, a holding device (1) for holding coral slices according to the present invention may comprise at least a first hollow tubular element (2) extending along a longitudinal axis and having a distal end (3), a proximal end (4), an inner side (not visible) and an outer side (5), and a second element (6) arranged coaxially with the proximal end (4) of the first element (2) and comprising a flared portion (7) defining a flat surface (10) constituting a surface extending circumferentially about the longitudinal axis of the first element, the flared portion (7) further comprising an edge (11) which together with the flat surface (10) defines a flange (12) around the longitudinal axis, where the device may have textured surfaces (8a, 8b). Advantageously, the flange (12) is deformable in a direction substantially parallel to the longitudinal axis of the tubular member (2).

[0079] Such a device having a flange may be referred to as a "valve" device in the following description.

[0080] FIG. 2 shows a cross section through a holding device (1) for holding coral slices, the holding device (1) comprising at least a first hollow tubular element (2) extending along a longitudinal axis and having a distal end (3), a proximal end (4), an inner side (13) and an outer side (5), and a second element (6) arranged coaxially with the proximal end (4) of the first element (2) and comprising a flared portion (7) defining a flat surface (10) constituting a surface extending circumferentially about the longitudinal axis of the first element (2), wherein the flared portion (7) further comprises an edge (11) which together with the flat surface (10) defines a flange (12) around the longitudinal axis, and the device may have a textured surface.

[0081] The first element has a body (9) between its distal end (3) and proximal end (4) defined by the inner surface (13) and the outer surface (5) of the first element.

[0082] Considered as a whole, the device according to the invention comprises a wall consisting, on the one hand, of the inner surface (13) of the first hollow tubular element (2) extended by the upper surface (14) of the second element (6) and, on the other hand, of the outer surface (5) of the first element (2) extended by the lower surface (15) of the second element (6).

[0083] The wall of the device comprises an inner surface and an outer surface. The inner surface of the wall is formed by the inner surface (13) of the first hollow tubular element (2) and the upper surface (14) of the second element (6). The outer surface of the wall is formed by the outer surface (5) of the first hollow tubular element (2) and the lower surface (15) of the second element (6). The outer and inner surfaces together represent the surfaces of the device of the invention.

[0084] The walls of the device have the necessary flexibility and rigidity to allow coral fragments to be inserted into the device and ensure that they are subsequently retained, and to allow the device to be inserted into and retained within holes in a supporting structure or reef on the seabed.

[0085] 3 shows an embodiment of a variant of the device (21) of the invention. The device (21) of the invention may comprise a second element (6) whose flared portion (7) comprises at least four elongated projections (16) (the fourth end is not visible in the figure because it is hidden), each projection having a distal end (17). The projections are arranged in the plane of the surface of the flared portion (7) and extend in the form of a circular arc in the direction of the longitudinal axis of the hollow tubular element (2) together with the flared portion (7) in such a way as to form a retaining member together with all the distal ends (17a, 17b, 17c; the fourth end is not visible in the figure because it is hidden by the projection that ends at end 17b) located around the longitudinal axis.

[0086] The first element has a body (9) between its distal end (3) and proximal end (4) defined by the inner surface (13) and the outer surface (5) of the first element.

[0087] The surface of the device (21) according to the invention is textured (8).

[0088] In particular, the flared portion (7) may comprise at least 5 to at least 15, in particular at least 7 to at least 12, in particular at least 10, elongate projections (16).

[0089] The projection has a distal end (17) and a base (18) that resides in the flared portion of the second element.

[0090] The elongate projections may be substantially flat. Alternatively, they may be substantially tubular, hollow or solid. Advantageously, they are of solid tubular form. Even more advantageously, they are substantially flat.

[0091] The elongate projections may have a constant cross-section between the flared portion of the second element and their respective distal ends, or alternatively, the cross-section may decrease substantially toward the distal ends of the projections in a manner that gives the distal ends a pointed shape.

[0092] Advantageously, the elongate projection (16) is substantially flattened and has a cross-section that decreases between the base (18) located at the flared portion (7) of the second element (6) in such a manner as to impart a pointed, or substantially pointed, shape to the distal end (17).

[0093] The elongated projection (16) may extend linearly substantially within the plane of the surface of the flared portion (7) of the second element (6) such that the distal end (17) of the projection (16) is substantially aligned with the base (18).

[0094] Alternatively, according to an alternative embodiment, the elongate projection may extend in an S-shaped or twisted configuration substantially within the plane of the surface of the flared portion of the second element such that the distal end of the projection is laterally offset relative to the position of the base.

[0095] FIG. 4 shows a cross section through the device (21) according to the invention shown in FIG.

[0096] According to a variant embodiment, the device (21) for holding coral pieces according to the invention comprises: a first hollow tubular element (2) extending along a longitudinal axis and having a distal end (3), a proximal end (4), an inner surface (13), and an outer surface (5); a second element (6) disposed coaxially with the proximal end (4) of the first element (2) and including a flared portion (7) defining a flat surface (10) that constitutes a surface extending circumferentially about the longitudinal axis of the first element (2); wherein the flared portion (7) comprises at least four elongated projections (16), each projection having a distal end (17), the projections being disposed in the plane of the surface of the flared portion (7) and extending in an arc of a circle in the direction of the longitudinal axis of the hollow tubular element (2) together with the flared portion (7) in such a manner as to form a retaining member together with all the distal ends (17a, 17b, 17c) located around the longitudinal axis; The device has a textured surface (8).

[0097] The above described devices having protrusions may be referred to as "ring" devices in the remainder of the description.

[0098] The dimensions of the "bulb" or "ring" type devices are variable and depend on the dimensions of the coral slices to be implanted. Using the 3D printing manufacturing method described below, it is easy to obtain a holding device of the present invention adapted to the dimensions of the coral fragments. There are no constraints on the dimensions of the holding device of the present invention, although in practice it is not useful to cut coral fragments with dimensions larger than 50 cm at their largest length.

[0099] The device of the present invention may have dimensions at its greatest length ranging from about 1 cm to about 25 cm, particularly from about 2 cm to about 20 cm, from about 5 cm to about 15 cm, or from about 8 cm to about 10 cm.

[0100] The device of the present invention may have dimensions at its widest width ranging from about 0.5 cm to about 20 cm, particularly from about 1 cm to about 15 cm, from about 4 cm to about 12 cm, or from about 8 cm to about 10 cm.

[0101] According to one variant embodiment, the first hollow tubular element may be closed at its distal end. Alternatively, it may be open at its distal end. The opening may have a diameter substantially equal to the width of the body of the first element. Alternatively, the opening may have a diameter smaller than the width of the body of the first element. According to yet another variant, the distal end may comprise at least one or more, at least two, holes of variable size and shape, for example circular.

[0102] The first hollow tubular element may have a cross-section of variable shape. It may be substantially circular, square, rectangular, trapezoidal, triangular or even elliptical. Advantageously, it is substantially circular. The cross-section of the first tubular member may be constant along the entire length of the member or may vary in shape along this length, for example having a substantially circular cross-section in a first section of the length of the tubular element and then a substantially square cross-section in a subsequent section.

[0103] Advantageously, the cross-section of the first hollow tubular element is substantially circular and constant along the entire length of the element.

[0104] The surface of the body of the hollow tubular element may be continuous between its proximal and distal ends or may have openings of various dimensions and sizes, in particular circular. In particular, the surface of the body of the hollow tubular element is continuous.

[0105] The presence of an opening at the distal end and / or at least one hole at the distal end and / or at least one hole in the body of the first element advantageously allows seawater or aquarium water to circulate within the holding device to more easily supply the coral slices with nutrients necessary for their growth and proliferation.

[0106] The devices of the invention described herein, such as (1) or (21), may be made as a unitary piece. In such a configuration, the second element (6) may constitute an extension of the proximal portion (4) of the first element (2).

[0107] Alternatively, the device of the invention described herein, e.g., (1) or (21), may be constructed from at least two parts, respectively represented by the first element (2) and the second element (6). In such a configuration, the first element (2) and the second element (6) may be assembled by any method known to those skilled in the art, e.g., by welding.

[0108] Advantageously, the holding device according to the invention is made as a one-piece unit.

[0109] The device of the invention described herein, e.g. (1) or (21), is advantageously intended to hold coral fragments or sections. The device is then placed in an environment that allows the fragments to multiply and develop into new colonies of coral. The expressions "coral fragments" or "coral fragments" are used interchangeably herein to mean coral fragments taken from an individual for the purpose of propagation via the fragments. Taking a fragment is a method of vegetative propagation consisting of giving birth to a new individual from a separated part or fragment of a part. The device is also intended to be placed by inserting it into a hole in a support structure or a natural reef present on the seabed, thereby providing the coral fragments with the environment necessary for their growth and their propagation.

[0110] The function of inserting a device according to the invention, e.g. (1) or (21), into a mounting hole is performed by the first hollow tubular element (2). The function of holding a coral piece by the device (1) is performed by the second element (6) arranged coaxially with the proximal end (4) of the first element (2) and provided with a flared portion (7) and the lumen or interior of the first hollow tubular element (2). The function of holding a coral piece by the device (21) is performed by the second element (6) arranged coaxially with the proximal end (4) of the first element (2) and provided with a flared portion (7) and the elongated projection (16) whose distal end (17) centered about the longitudinal axis forms a holding member.

[0111] The "ring" device described above may be advantageously suitable for holding fragments of branched or massive coral. In such implementations, the coral fragments may be inserted between the distal ends of the elongated prongs. The coral fragments are inserted such that at least one, and preferably both, ends of the fragments are held between the two prongs and extend outwardly from the device. In particular, the device (21) of the present invention having elongated prongs (16) may be suitable for massive coral. Figure 5 shows a device (21) according to the present invention with a fragment of massive coral (22) fastened to the elongated prongs (16).

[0112] A "ring" type device may have rigid walls, for example, with a Shore A hardness of around 95 to around 98, in particular around 96 to around 97. In particular, such a device may have rigid walls with a Shore A hardness of around 98.

[0113] The "valve" device described therein may be advantageously suitable for holding branched coral fragments. In such implementations, the coral fragments may be inserted along the entire length of the first element. Retention of the coral may be facilitated by the presence of spikes, as described below. The coral fragments are inserted in a manner that keeps a portion of the fragment above the flared portion of the second element.

[0114] The device of the invention with flanges may be particularly suitable for branching coral. Figure 6 shows a device (1) according to the invention with a branching coral fragment (23).

[0115] A "valve" type device may have walls with a hardness in the range of, for example, around 85 to around 98 Shore A, particularly around 90 to around 95 Shore A, and especially around 92 Shore A. In particular, such a device may have rigid walls with a Shore A hardness of around 92.

[0116] Once the coral fragments are inserted into the "bulb" type retention device, the device may be placed on a support structure, e.g., a support structure defined below or a natural reef on the sea floor, and the deformable flange may be folded downwards towards the distal end of the hollow tubular element to become fixed to the surface of the support, whereby the flange promotes attachment and retention of the device to the support through frictional forces generated by its textured surface.

[0117] Figures 7 and 8 show a device (1) according to the invention, comprising a branched coral fragment (23) inserted into a hole (25) in a support (24). Figure 7 shows the device with the flange (12) raised to an initial position. Figure 8 shows the device with the flange (12) deformed and fixed to the surface of the support (24).

[0118] Alternatively, the "bulb" device may be suitable for holding the "ring" device itself with a segment of branching or clumping coral.

[0119] Figures 9 and 10 show a "ring" type device (21) of the present invention with a chunk of coral (22) inserted into a "bulb" type retention device (1).

[0120] The above described "valve" or "ring" devices may also comprise at least one, in particular a plurality of, spikes arranged at least on the inner surface of the wall of the device.

[0121] According to one embodiment, the one or more spikes may be located on the inner surface of the first element. The one or more spikes may be located at the proximal end. Alternatively, or in addition, they may be located on the entire inner surface of the body of the first element, or also at the distal end.

[0122] According to one variant embodiment, one or more of said spikes may be arranged on the upper surface of said second element.

[0123] The spikes may be arranged around the circumference of the first hollow tubular element, or longitudinally along the longitudinal axis of the first element, or around the circumference and along the longitudinal axis so as to be regularly arranged on the inner surface of the first element. The density of the spikes is adjusted to increase retention on the coral fragments (or any other element inserted into the device of the present invention) without preventing or impeding the insertion of the coral fragments.

[0124] The presence of the spikes advantageously makes it possible to facilitate retention of the coral fragments inserted in the hollow tubular element, or, if applicable, retention of a second device for holding the coral fragments inserted in the first device.

[0125] FIG. 11 shows a cross section through a device (1) according to the present invention with a plurality of spikes (26) disposed on the inner surface (13) of the first element (2) and on the top surface (14) of the second element (6).

[0126] The device according to the invention has a textured surface (8). The textured surface may have an average surface roughness capable of generating friction with the surface of the coral slice and / or with the contact points of the support structure. For the purposes of the present invention, the term "textured" means that the surface of the wall is rough. The texturing or roughness of the surface of the wall is present on the outer surface of the wall or on its inner surface. Advantageously, the texturing or roughness is present on the inner surface and on the outer surface.

[0127] The surface texturing of the inner face of the device allows the coral slice to be immobilized and held within the device through the phenomenon of friction that occurs between the texture of the surface and the surface of the coral slice.

[0128] The texturing of the surface of the outer face of the device makes it possible to immobilize and retain the device within the support through the phenomenon of friction that occurs between the textured surface and the surface of the support into which the device is inserted.

[0129] The term "textured" does not imply the use of a particular material or manufacturing method (e.g., a finish or coating applied thereto). The term "textured" is used to refer to a high friction surface profile, as opposed to a smooth or polished surface profile. A textured face, or surface, may be composed of a number of individual components, which are in proximity to one another and together define a number of concave and convex elements. The convex and concave elements are not limited to any particular shape. Concave elements suitable for the present invention are not limited to any particular shape and may have, for example, the shape of a cavity, valley, gap, recess, groove, streak, or indentation. Convex elements suitable for the present invention are not limited to any particular shape and may have, for example, the shape of a bulge, bump, protrusion, corner, ridge, bulge, rise, or protrusion.

[0130] The texturing is not limited to any particular shape. Texturing suitable for the present invention may have the shape of, for example, grooves, streaks, grooves, indentations, meshwork, geometric networks, or interlocking.

[0131] According to one embodiment, the texturing of the surface of the device of the invention and the texturing of the surface of a support, such as a support structure of the invention, may have the same or similar configuration, such that the convex elements of the surface of the device can fit into the concave elements of the surface of the support, and the convex elements of the surface of the support can fit into the concave elements of the surface of the device. The same or similar configuration of the texturing generally allows a greater surface friction to be generated, since the opposing components are easily put into interfering / interlocking contact with each other.

[0132] According to an advantageous embodiment, the surface of the device and the surface of the support structure have a texturing formed by sets of grooves, striations or grooves arranged substantially parallel to one another.

[0133] The texturing of the surface of the device according to the invention may be defined by the surface roughness, in particular the average surface roughness. The surface roughness corresponds to the irregularities present on the surface and caused by height differences. The surface roughness may be established by measuring the surface contour using a roughness measuring device. Various roughness measuring methods may be applied. As examples of methods for measuring the surface roughness, in particular the average surface roughness, contact methods, such as stylus methods, or optical methods, for example using optical profilometers, may be mentioned.

[0134] In what is called the stylus method, a sensor tip is used at a constant speed across the surface of a device. The tip scans the surface point by point. A contact measurement of the average surface roughness can be obtained, for example, using an instrument such as the Surftest SJ-210 or Surftest SJ-410 sold by Mitutoyo Corporation.

[0135] Optical measurements of the average surface roughness can be obtained using an optical profilometer type instrument, such as a NewView™ 9000 Optical Profilometer manufactured by Zygo Corporation, or using a Rainbow white light chromatic confocal sensor sold by OGP.

[0136] According to DIN EN ISO 4288 (as of the filing date), roughness characteristics are measured in five separate measurement sections. Most roughness characteristics, such as the arithmetic mean roughness value (Ra), the mean roughness depth (Rz) or the maximum roughness depth (Rmax), are calculated in the separate measurement sections (the length of the separate measurement sections is numerically equal to the upper wavelength). Characteristic values, such as the material ratio (Rmr) or the total height of the roughness characteristic (Rt), are taken into account over the entire roughness characteristic. Roughness characteristics or roughness parameters are based on the international standard DIN EN ISO 4287 (as of the filing date).

[0137] The average roughness Ra is defined as the arithmetic mean of the absolute values ​​of the characteristic deviations within a reference section.

[0138] The average surface roughness of a device of the present invention may be measured parallel to the longitudinal axis of the element.

[0139] The average surface roughness of a device of the present invention may be measured perpendicular to the scratches present on the surface.

[0140] The textured surface of a device according to the invention may have an average surface roughness of at least 0.5 μm, in particular a surface roughness in the range of around 0.5 μm to around 320 μm. In particular, a device according to the invention may have an average surface roughness in the range of around 1 μm to around 300 μm, around 2 μm to around 250 μm, around 4 μm to around 200 μm, around 8 μm to around 150 μm, around 10 μm to around 120 μm, around 15 μm to around 100 μm, around 20 μm to around 80 μm, or around 30 μm to around 50 μm.

[0141] Devices according to the invention may have an average surface roughness of around 0.5 μm, around 1 μm, around 2 μm, around 5 μm, around 8 μm, around 10 μm, around 15 μm, around 20 μm, around 30 μm, around 40 μm, around 50 μm, around 80 μm, around 100 μm, around 120 μm, around 150 μm, around 180 μm, around 200 μm, around 250 μm, around 280 μm, around 300 μm, or around 320 μm.

[0142] As will be explained in detail below, the surface roughness, or texturing, of the devices of the invention is determined inter alia by the parameters of the method for manufacturing the device, and thus each manufacturing method corresponds to one expected surface roughness.

[0143] The walls of the device of the invention have a flexibility or hardness suitable for inserting and holding coral fragments in the device and for inserting and holding the device in a natural or manufactured support. The flexibility or hardness of the device of the invention can be measured using the Shore hardness scale. Hardness can be measured using a Shore durometer. Such a device determines the penetration depth of a standardized indenter, a frustum-shaped tip, when applied to a sample, which, when penetrating the sample, causes a reaction against a calibrated metal spring. The scale for measuring the hardness of the walls of the device according to the invention is the Shore A scale. The measurement of the hardness according to the Shore A scale can be performed using a frustum with a cone angle of 35°, a spring force of 8.065 N, and a pressure force of 12.5 N.

[0144] The retention device may be colored to promote biomimicry with the coral fragments. Coloration of the device according to the invention is obtained by coloring the materials used to manufacture it, as described in detail below.

[0145] As shown in FIG. 15, the device of the present invention may be inserted into a support, which may be either man-made, such as a support structure as described below, or natural, such as a reef on the ocean floor.

[0146] support structure One of the subject matters of the present invention relates to a support structure for at least one device of the present invention. Such a structure comprises a continuous surface with at least one hole configured to receive the distal end of a device described herein. The surface of the structure is textured.

[0147] The support structure may have any possible shape. In particular, it may have ridges and cavities intended to mimic the natural relief of a coral reef. Alternatively, it may have a geometric shape, such as a cube, a parallelepiped, or a polygon with at least one face of sufficient dimensions to allow the structure to be stably placed on the bottom of the aquarium or on the seabed.

[0148] FIG. 12 shows an arbitrarily shaped support structure (27) having a continuous surface (38) with ridges (28) and recesses (29) and, where applicable, a plurality of holes (30) configured to receive hollow tubular elements (2) of the device (1, 21), where the surface is textured (31).

[0149] The surface texturing of the support structure according to the present invention may have the same characteristics as the surface texturing of the device of the present invention, in particular as described above, where the average surface roughness may also be measured as described above for the device.

[0150] The textured surface of the support structure according to the invention may have an average surface roughness of at least 0.5 μm, in particular an average surface roughness in the range of around 10 μm to around 770 μm. In particular, the device of the invention may have an average surface roughness in the range of around 15 μm to around 700 μm, around 20 μm to around 600 μm, around 40 μm to around 500 μm, around 50 μm to around 400 μm, around 80 μm to around 300 μm, around 100 μm to around 250 μm, around 120 μm to around 200 μm, or around 150 μm to around 180 μm.

[0151] Support structures according to the present invention may have an average surface roughness of around 0.5 μm, around 10 μm, around 15 μm, around 20 μm, around 40 μm, around 50 μm, around 80 μm, around 100 μm, around 120 μm, around 150 μm, around 180 μm, around 200 μm, around 250 μm, around 300 μm, around 400 μm, around 500 μm, around 600 μm, around 700 μm, or around 770 μm.

[0152] According to an advantageous embodiment, said surface (38) of the support structure (27) has a texturing (31) consisting of sets of grooves, striations or grooves arranged substantially parallel to one another.

[0153] Said surface of the support structure (27) according to the invention is provided with at least one hole (30) adapted to receive said hollow tubular element (2) of the device (1, 21) according to the invention.

[0154] In particular, the support structure has a plurality of holes 30. The holes are arranged in a random or chaotic arrangement on the surface of the structure. Alternatively, the holes can be arranged in an orderly manner.

[0155] The holes are spaced apart from each other to allow each coral slice placed in each of the holes and present in the holding device of the present invention to grow without disturbing the growth and proliferation of the adjacent slices. For example, the holes can be spaced apart from each other at a distance of at least 5 cm, particularly at least 8 cm, particularly at least 10 cm, particularly at least 12 cm, or at least 15 cm. The distance between two adjacent holes can be in the range of about 5 cm to about 15 cm, particularly about 8 cm to about 12 cm, or can be about 10 cm.

[0156] According to one variant embodiment, the support structure may be solid. In this variant, the holes are hollowed or drilled in the mass.

[0157] According to another variant embodiment, the support structure may be hollow and include a wall. In this variant, the holes may be drilled or perforated in the wall of the hollow structure. Alternatively, the hollow structure may be molded by injection molding or extrusion blow molding, for example with a mold that is provided with spikes to form the holes.

[0158] According to yet another variant embodiment, the support structure may comprise a wall and an interior consisting of a number of cells, which are advantageously in communication with one another. Such a structure may be obtained by 3D printing with an infill of honeycomb (or hexagonal) type. In 3D printing, the infill reflects the degree of filling of the printed product. The denser the infill pattern, the more the interior of the printed product will be filled. The support structure according to the invention may comprise an infill density in the range of 1-50%.

[0159] FIG. 13 shows a cross section through an arbitrarily shaped support structure (27) having ridges (28) and recesses (29), with a wall (32) and an interior made up of a number of cells (33).

[0160] Figure 14 shows a cross section through a support structure (27) of any shape, with walls (32) having ridges (28) and recesses (29), and an interior made up of a number of cells (33), comprising a number of holes (30) into which the devices (1) or (21) for holding the coral fragments (22) or (23) are inserted.

[0161] In the case of hollow structures or structures with a honeycomb-like interior, the holes may advantageously open into the interior of the structure to allow communication between the exterior and the interior of the structure. This may allow the structure, submerged in a water tank or placed on the seabed, to be filled with water. The structure thus filled may be ballasted and rest stably on the bottom of the water tank or on the seabed.

[0162] According to one variant embodiment, the support structure according to the invention may have an interior made up of a plurality of cells communicating with each other and, directly or indirectly, with said holes, each cell defining a cavity having a wall shared with at least one neighbouring cell and at least one opening allowing communication between said cavity of said cell and the cavity of at least one neighbouring cell.

[0163] The number of cells inside the support structure of the invention obtained by 3D printing and their size depend in particular on the type of infill chosen and its density, which is adjusted to obtain the best compromise in terms of solidity, weight and cost of the part produced, and to ensure that the support structure is filled with water when submerged.

[0164] The dimensions of the support structure for the "bulb" or "ring" type devices may vary widely and may depend, among other things, on the final installation of the support structure, i.e. the aquarium or seabed, and on the number of holding devices to be installed, etc. In practice, the support structure may have dimensions ranging from a few centimetres in height, width and length to tens of centimetres. For structures with particularly large dimensions, these may be expressed in metres.

[0165] A support structure according to the present invention may comprise at least one device according to the present invention. Preferably, the structure is submerged and then the coral slice holding device according to the present invention is placed in the hole. In case of a hollow structure or a structure with a honeycomb-like interior, this advantageously allows the structure to be filled with water and ballasted.

[0166] According to one embodiment, when using either a "bulb" type device as a device for directly holding a coral slice or an indirect holding device comprising a "ring" type device containing the slice, the flange can be secured to the surface of the structure by deformation. The friction generated by contacting the textured surface of the flange with the textured surface of the support structure advantageously allows for stable placement of the holding device within the structure.

[0167] The device for holding coral slices according to the present invention is textured over its entire surface. Contact between the textured surface of the device of the present invention and the edge of the hole into which it is inserted makes it possible to generate friction, which advantageously allows for stable placement of the holding device within the structure.

[0168] As with the retention device, the support structure according to the invention may be colored to facilitate biomimicry with the coral fragments. Preferably, the support structure according to the invention may mimic the appearance of a common hardy coral, such as Porites furcata, in both its shape and color, to signal to neighboring corals that it is an environment conducive to coral growth. Coloration of the support structure according to the invention may be obtained by coloring the materials used to manufacture it, as described in detail below.

[0169] Biodegradable Polymers The retention device and / or support structure according to the present invention may be made from a biodegradable polymer that includes at least one calcium salt.

[0170] Thus, according to one of its subjects, the present invention relates to the use of a biodegradable polymer comprising at least one calcium salt for manufacturing a device for holding coral slices according to the invention or a support structure according to the invention.

[0171] A polymer is a macromolecule made up of chains of repeating units. Biodegradable polymers are polymers that degrade rapidly over time into biocompatible (or environmentally friendly) by-products.

[0172] Biodegradable polymers suitable for the present invention may be adapted for use in methods of manufacturing devices or support structures according to the present invention by molding, for example by injection molding or extrusion blow molding, or by 3D printing.

[0173] Advantageously, biodegradable polymers comprising at least one calcium salt may be suitable for the method of manufacturing the devices and structures of the invention by 3D printing.

[0174] Polymers that can be used in 3D printing are supplied in the form of filaments.

[0175] Polymers suitable for the present invention may have an extrusion temperature of from 150°C to 220°C, especially from 180°C to 190°C.

[0176] Biodegradable polymers suitable for the present invention may be selected from polylactic acid polymers, glycolic acid polymers, polyhydroxyalkanoates, poly(alkylene succinic acids), polycaprolactones, polytrimethylene terephthalates (PTT), and combinations thereof.

[0177] The polyhydroxyalkanoate may be selected from polyhydroxybutyrate (PHB), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx), and combinations thereof.

[0178] The poly(alkylene succinic acid) may be selected from poly(ethylene succinic acid) (PESu), poly(propylene succinic acid) (PPSu), poly(butylene succinic acid) (PBSu), and combinations thereof.

[0179] In particular, the biodegradable polymer can be a polylactic acid (PLA) polymer.

[0180] The calcium salt suitable for the present invention may be an organic calcium salt. The organic salt may be selected from calcium carbonate, calcium citrate, hydroxyapatite, calcium lysinate, and combinations thereof. In particular, the calcium salt is calcium carbonate. Calcium carbonate is one of the components that make up the coral skeleton.

[0181] The calcium carbonate may be introduced into the polymer in any form suitable for the present invention. In particular, the calcium carbonate may be introduced into the polymer in the form of crushed oyster shells, e.g. crushed oyster shells.

[0182] The particles of calcium salt, especially calcium carbonate, have a particle size that does not interfere with the diameter of the extrusion nozzle of the 3D printer. For example, the particle size of the calcium salt, especially calcium carbonate, can be less than 250 μm.

[0183] The calcium salt-containing polymer may contain other compounds intended to improve the biocompatibility, biomimicry, printability, roughness, and / or hardness of a device or support structure according to the invention.

[0184] For example, biomimicry is enhanced by adding calcium salts and dyes to the printing polymer that mimic the colors of coral.

[0185] The roughness and / or hardness of a device or support structure according to the invention may be increased by adding wood or stone particles to the printing polymer.

[0186] As additional compounds making it possible to adjust the hardness of a device or structure according to the invention, mention may be made, for example, of chitosan, chitin, starch or alginates.

[0187] As additives that may be used with the polymers used in the present invention, mention may also be made of dyes, which may be advantageously used to obtain biomimetic effects.

[0188] Many kinds of dyes can be used. Preferably, biocompatible or biologically derived dyes are used. As examples of dyes that can be used in the present invention, mention can be made of curcumin, bixin, anthocyanin, chlorophyll, astaxanthin, naphthoquinone, carotenoids, or dyes extracted from grapes, strawberries, apples, cherries, or red cabbage.

[0189] Coloration of the polymers that may be used in the methods of the present invention may be achieved by incorporating a parent compound into the biopolymer during its production prior to extrusion as a filament for 3D printing.

[0190] A suitable polymer for the present invention may be a lactic acid polymer including chitosan and hydroxyapatite, as described in Nazeer et al. (Materials Today Communications, Vol. 25, 2020, 101515: 3D printed poly(lactic acid) scaffolds modified with chitosan and hydroxyapatite for bone repair applications, doi.org / 10.1016 / j.mtcomm.2020.101515).

[0191] A suitable polymer for the present invention may be a lactic acid polymer containing hydroxyapatite, as described in Dubinenko et al. (Journal of Applied Polymer Science (2021; 138:e49662): Highly filled poly(l-lactic acid) / hydroxyapatite composite for 3D printing of personalized bone tissue engineering scaffolds. doi.org / 10.1002 / app.49662).

[0192] A suitable polymer for the present invention may be a lactic acid polymer containing calcium carbonate as described in Gayer et al. (Materials Science and Engineering: C, Vol. 101, 2019, pages 660-673: Development of a solvent-free polylactide / calcium carbonate composite for selective laser sintering of bone tissue engineering scaffolds; doi.org / 10.1016 / j.msec.2019.03.101.) or as described in Nunes et al. (International Journal of Innovative Science, Engineering & Technology, Vol. 4, Issue 6, June 2017: Evaluation of the Poly(Lactic Acid) and Calcium Carbonate Effects on the Mechanical and Morphological Properties in PBAT Blends and Composites).

[0193] A biodegradable polymer comprising at least one calcium salt suitable for the present invention may be a lactic acid polymer comprising calcium carbonate, advantageously introduced into said polymer in the form of ground oyster shells, for example ground oyster shells.

[0194] As an example of a lactic acid polymer containing calcium carbonate suitable for the present invention, mention may also be made of the filament polymer Francofil 1.75 mm PLA filament, an oyster by-product sold by the company Francofil under the item number FRF341674.

[0195] Manufacturing method Devices or support structures according to the present invention may be manufactured by any method known in the art, particularly those methods that can be used in conjunction with polymers that contain calcium salts as described above.

[0196] The manufacturing method suitable for the present invention allows for texturing of the surface of the device or the support structure.

[0197] The method for manufacturing a device or structure of the invention may be a three-dimensional printing (or 3D printing) method, which advantageously makes it possible to obtain a texturing of the surface of said device or structure during the printing process.

[0198] Depending on the product being manufactured, ie a device or a support structure, the printing method may involve different parameters and printing modes.

[0199] 3D printing methods are well known.

[0200] Prior to printing, the device or structure according to the invention is modeled. Such a model can be developed using various software, for example Catia, Fusion360, Solidworks, or Creo, and the final format is generated in a machine-readable format, for example STEP, STL, or OBJ. The resulting model is then sliced ​​into layers by a slicing software. The dimensions of the layers (length, diameter) are adapted to the printing equipment used, in particular the extrusion nozzle, the dimensions of the polymer filament, and also the extrusion rate / second. The layers must be thick and close enough to each other to ensure the solidity of the printed object, but at the same time far enough and / or thin enough to give the printed object the required flexibility. The software converts the model into coordinates understood by the 3D printer, and the polymer is deposited layer-by-layer on top of each other according to those coordinates during the printing process. At output, the model is in the form of a text file with a file extension of ".gcode".

[0201] The device or structure according to the invention can be printed using various 3D printing techniques. 3D printing is an additive manufacturing technique in which 3D objects are created by depositing layers of material to create a physical object. Printers working by extrusion and fused deposition modeling (FDM) use polymer filaments, e.g. PLA (lactic acid polymer), ABS (acrylonitrile butadiene styrene), PC (polycarbonate), PET-G (glycolized polyethylene terephthalate), printers for 3D printing by stereolithography (SLA) or DLP (digital light processing) use resins, and SLS (selective laser sintering) techniques use powdered materials, e.g. nylon.

[0202] In particular, methods for manufacturing devices or support structures according to the present invention may use extrusion and fused deposition modeling techniques ("fused filament modeling" (FFM), "melted and extruded modeling" (MEM), "fused filament fabrication" (FFF), or "fused deposition method" (FDM)).

[0203] FIG. 16 illustrates a schematic of fused deposition modeling, in which a 3D printer nozzle (34) deposits successive layers (36) of molten polymer onto a work surface (35).

[0204] As shown in Figure 17, the layer of molten polymer (36) extruded and deposited by the 3D printer nozzle leads to the formation of scratches (37) on the surface of the manufactured product. The thicker the layer of molten polymer deposited by the 3D printer nozzle, the deeper the scratches will be and the higher the average surface roughness value. The thinner the layer of molten polymer deposited by the 3D printer nozzle, the less deep the scratches will be and the lower the average surface roughness value.

[0205] The method for 3D printing a device according to the invention can be carried out in "vase" mode. This 3D printing mode means that the walls are printed as a single layer, without any discontinuity of the extruder (or printing nozzle). The z-axis is raised incrementally, instead of being produced layer by layer, as in standard printing. Such printing is advantageously carried out without infill. The layer is deposited incrementally on itself, by rotating the printing nozzle about the longitudinal axis of the device. The stacking of the layers leads to the formation of striations that form the texturing of the surface.

[0206] 18 shows 3D printing of a "valve" shaped holding device of the present invention using a method by deposition of layers of molten polymer. The 3D printing nozzle (34) advances along the Z-axis, depositing successive stacked layers (36) of molten polymer to form the outline of the "valve" shaped device (1) without infill (vase mode).

[0207] The device according to the present invention can be printed by 3D printing using fused deposition modeling technology with an extrusion nozzle having a diameter of around 0.4 mm. The printing speed, layer thickness and extrusion temperature depend on the polymer used and the nozzle used. Usually, the layer thickness should not exceed 80% of the nozzle diameter.

[0208] For example, in the case of a lactic acid polymer containing calcium carbonate, such as that sold by Francofil under the part number FRF341674, the nozzle temperature may be around 200°C (185°C to 230°C), the printing surface temperature may be around 30°C (20°C to 30°C), the printing speed may be around 60 mm / s (40 to 100 mm / s) and the layer height may be around 0.5 μm to around 320 μm.

[0209] The support structure according to the invention can be printed by 3D printing using fused deposition modeling technology with an extrusion nozzle having a diameter of around 1.2 mm. The printing speed, layer thickness and extrusion temperature depend on the polymer used, the nozzle used, and the density and model of the infill chosen.

[0210] The support structure according to the invention may be printed in 3D using a lactic acid polymer containing calcium carbonate, such as that sold by the company Francofil under the part number FRF341674, the specific characteristics of which are described above. The layer height may range from around 0.5 μm to around 770 μm.

[0211] Printing can be carried out, for example, with a maximum layer thickness of around 3 mm. Such a layer thickness makes it possible to give the object good solidity and good water resistance, while maintaining a striated appearance with the necessary roughness for the attachment of the coral.

[0212] The number of cells inside the support structure of the invention obtained by 3D printing and their size depend in particular on the type of infill chosen and its density. The density and model of the infill are adjusted to obtain the best compromise in terms of solidity, weight and cost of the part produced and to ensure that the support structure is filled with water when submerged. Various infills are available, namely with cell shapes of hexagonal, triangular, linear, grid, wave, etc.

[0213] The method for 3D printing a support structure according to the present invention can be performed with a honeycomb shaped infill (or infill), which can have a density of 1-50%.

[0214] The holes in the support structure according to the invention may be obtained by drilling or punching, for example using a drill or a heated pin, either during or after printing.

[0215] According to one variant embodiment, the method for manufacturing the device or structure of the invention can be a method for extrusion blow molding a polymer into a mold that represents in hollow form the device or structure of the invention to be reproduced. Alternatively, the manufacturing method can be an injection molding method. In such a method, the walls of the mold can have as recesses the texturing pattern to be printed on the surface of the device or structure.

[0216] In the case of a structure according to the invention, the method may include the step of drilling holes by any suitable method, for example by means of a drill or a heated pin, for later receiving the holding device according to the invention.

[0217] According to yet another alternative embodiment, the mold used to manufacture a device according to the invention may not have a texturing pattern printed on its surface, where the texturing can be added later by an engraving process.

[0218] The invention is not limited to the examples just described, in particular the features of the examples described can be combined with one another in variants not described, whereby other variants and improvements are conceivable without departing from the scope of the invention.

[0219] Cited literature JPEG2024517168000002.jpg152170

Claims

1. A device (1, 21) for holding coral pieces, the device comprising: a first hollow tubular element (2) extending along a longitudinal axis and having a distal end (3), a proximal end (4), an inner surface (13), and an outer surface (5); a second element (6) disposed coaxially with the proximal end (4) of the first element (2) and including a flared portion (7) defining a flat surface (10) constituting a surface extending circumferentially about the longitudinal axis of the first element; Equipped with wherein the device has a textured surface (8) on the inner side (13), The device.

2. 2. The device (1) according to claim 1, wherein the flared portion (7) has an edge (11) which, together with the flat surface (10), defines a flange (12) around the longitudinal axis, in particular the flange (12) being advantageously deformable in a direction substantially parallel to the longitudinal axis of the tubular element (2).

3. 2. The device (21) of claim 1, wherein the flared portion (7) of the second element (6) comprises at least four elongated projections (16), each projection having a distal end (17), the projections being arranged on the plane of the surface of the flared portion (7) and extending, together with the flared portion (7), in an arc of a circle in the direction of the longitudinal axis of the hollow tubular element (2) in such a manner as to form a retaining member together with all the distal ends (17a, 17b, 17c) located around the longitudinal axis.

4. A device according to any one of claims 1 to 3, wherein the first element (2) is provided with at least one spike (26) extending from the inner surface (13) towards the inside of the element.

5. 3. The device of claim 1 or 2, wherein the device is formed from a material comprising at least one biodegradable polymer and at least one calcium salt.

6. A support structure (27) for at least one device as described in claim 1, the support structure (27) having a continuous surface (38) with at least one hole (30) configured to receive a hollow tubular element (2) of the device (1, 21) as described in claim 1, wherein the surface is textured (31).

7. 7. The support structure (27) of claim 6, wherein the support structure (27) has an interior comprised of a plurality of cells (33), the plurality of cells communicating with each other and with the holes (30), directly or indirectly.

8. A support structure (27) according to claim 6, comprising at least one device (1, 21) according to claim 1 or 2.

9. The support structure (27) comprises at least one device (1) as described in claim 2 arranged in a hole (30) in the support structure, wherein the device (1) comprises a flange (12) and the flange (12) is fixed to the surface (38) of the structure (27).

10. A method for manufacturing a device (1, 21) for holding coral slices according to claim 1 or a support structure (27) according to claim 6, comprising at least one step consisting of 3D printing the device (1, 21) or the support structure (27).

11. A method of using a biodegradable polymer containing at least one calcium salt for manufacturing a device (1, 21) for holding coral slices as described in claim 1 or a support structure (27) as described in claim 6.

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