WO2015092271A1

WO2015092271A1 - Process for manufacturing a surface or volume article from bundles of fibres and resin

Info

Publication number: WO2015092271A1
Application number: PCT/FR2014/053385
Authority: WO
Inventors: Yves NUNZIATO
Original assignee: Ads Design
Priority date: 2013-12-18
Filing date: 2014-12-17
Publication date: 2015-06-25
Also published as: FR3014732A1; FR3014732B1

Abstract

Process for manufacturing a surface or volume article from bundles (2) of fibres and resin, said process comprising steps consisting in: • - forming at least two fibre strands (1a, 1b) • - coating these fibre strands (1a, 1b) with resin by passing each of them into a separate immersion bath (4a, 4b), these baths (4a, 4b) containing resin of different colours and decorative pigments, • - wiping the strands (1a, 1b) coated with resin and joining them together into a single bundle (2) of fibres, • - winding this bundle (2) of fibres onto a tensioning device (3) so as to create a surface or volume shape according to a predefined structure corresponding to that of the article to be manufactured, being characterized in that it consists, beforehand, in selecting porous fibres, and in that it consists in simultaneously carrying out a coating and an impregnation of the fibre in order to form, ultimately, a bundle (2) of reinforced fibres, and more specifically a bundle (2) of resin reinforced by fibres which are themselves reinforced with resin.

Description

METHOD FOR MANUFACTURING SURFACE OBJECT OR

VOLUMIC FROM FIBER AND RESIN BEAMS

Technical field of the _invention. . The subject of the invention is a method making it possible to manufacture a surface or volume object from coated fiber cords and amalgamated with resin,

It concerns the technical field of the shaping of objects in two dimensions (2D) or in 3 dimensions (3D).

State of the art. Indoor or garden furniture, made of natural basketry materials, such as willow, rattan or similar natural materials, are known. Such products are also manufactured with cords or strips of flexible PVC or polyethylene dyed in the mass. It is also known from patent document DE 10.2005.060.554

(ASSON WAWER), a manufacturing technique using resin-coated fiber strands for the manufacture of furniture, utensils, space separators, accessories, wall decorations, pavilions and similar objects in volumetric or surface form, intended for to indoor or outdoor spaces. Several strands of roving (fiberglass) are united in at least two bundles of strands, coated in separate immersion baths containing resin of different colors and decorative pigments. After coating and wiping with a scraper, the strands are united under a low pressure into a single bundle which is in the form of a resin bead which is reinforced by fiberglass. The transformation of these beams into an ornamental structure of surface or volume form is as follows: the beam is wound under tension on a tensioning device, starting from a defined point of attachment and alternating on diametrically opposed points of reference , until the planned drawing and the voluminal object with its maiilage or ornamental structure is completed. Once the finished product, the final hardening of the resin is done in the open air using a hot air stream or using the heat radiation of a light source, infrared or UV .

This manufacturing process is not completely satisfactory for several reasons. Firstly, the glass fibers have a high irritating power likely to annoy the user, especially when the manufactured object is intended to be in contact with the latter, such as a chair or a garden chair, for example. In addition, fiberglass bundles that are simply coated with resin are generally not sufficient to provide a chair or chair with sufficient mechanical strength. Indeed, it is necessary to use stiffened reinforcing bandages and / or bundles of glass fibers of different thicknesses.

The invention aims to remedy this state of affairs. In particular, an object of the invention is to provide more resistant objects, that is to say having a better intrinsic resistance.

Another object of the invention is to propose a method of manufacture of the type described in the aforementioned DE 10.2005.060.554, but making it possible to obtain more stable objects. Disclosure of the invention.

The solution proposed by the invention is a method of manufacturing surface or volume objects from fiber strands and resin, said method comprising the steps of:

- form at least two strands of fibers,

resinously coat these fiber strands by passing each of them in a separate immersion bath, these baths containing resin of different colors and decorative pigments,

- wipe the resin-coated strands and join them into a single bundle of fibers,

winding this bundle of fibers on a tensioning device so as to create a surface or volume shape according to a predefined structure corresponding to that of the object to be manufactured,

This method is remarkable in that it comprises, beforehand, a step of selecting porous fibers, and at the same time performing a coating and an impregnation of the fiber to form, in fine, a bundle of reinforced fibers, and more specifically a beam of resin armed with fibers that are themselves armed with resin.

Unlike the case of glass fibers, the presence of pores in the fibers allows an increase in the amount of resin they contain. After the hardening step, this characteristic makes it possible to obtain elements having greater rigidity and thus being much more resistant. The fibers become armored fibers that are stiffened by the resin that hardens in the pores.

Other advantageous features of the invention are listed below. Each of these characteristics can be considered alone or in combination with Its remarkable characteristics defined above, which Outstanding characteristics are not essential as tiles to solve technical problems that the following features propose to solve:

a version of the process consists in choosing fibers having a porosity greater than 20%,

a version of the process consists in choosing porous fibers having a density of less than 2 g / cm ³ and having a linear density of between 400 g / km and 2400 g / km,

another version of the process consists in choosing fibers having a linear density of between 400 g / km and 600 g / km,

a version of the process may consist in choosing fibers having a linear density of between 600 g / km and 2400 g / km,

another version of the process may be such that the fibers are fibers of plant origin chosen from the following family: flax fibers, hemp fibers, cotton fibers, seagrass fibers, coconut fibers, palm tree, rattan fiber, banana fiber,

another version of the process may be such that the fibers are fibers of inorganic origin chosen from the following family: crystal fibers, silica fibers, basalt fibers, carbon fibers,

another version of the process may be such that the fibers are fibers of animal origin chosen from the following family: wool fibers, silk fibers,

another version of the process consists in keeping the resin bath at a temperature greater than 35 ° C. during the immersion phase,

another version of the process consists in leaving the fiber strands in the resin baths between 1 second and 20 seconds during the immersion phase,

- Yet another version of the process has a wiping step which consists in passing the strands through a scraper so as to force the penetration of the resin to the heart of the fibers. The invention also relates to products or objects which consist of fiber bundles embedded in resin, which fibers comprise resin-filled pores which impart a character of reinforced fiber and, therefore, a high intrinsic strength.

Description of the figures.

Other advantages and features of the invention will appear better on reading the description of a preferred embodiment which will follow, with reference to the accompanying drawings, carried out as indicative and non-limiting examples and in which;

FIG. 1 is a schematic view of the manufacturing method which is the subject of the invention,

- Figure 2 is a representation of a tensioning device according to the invention.

The method according to the invention is intended for the manufacture of surface or volume objects, and more particularly objects composed of natural fibers. It makes it possible to create more resistant elements while using materials with a low ecological impact and a more pleasant use for the user.

Firstly, several strands (1a, 1b) of fibers are used in order to produce a bundle (2). In Fig. 1, two strands (1a, 1b) are used, but an identical method may be used to gather a larger number of strands. The beams (2) formed are subsequently wound around a tensioning device (3). The fibers are chosen from a multitude of natural fibers, for example fibers of plant origin, fibers of inorganic origin or fibers of animal origin. For example, fibers of plant origin may be weigh the fiber using a microbalance to determine its starting weight (Pi),

to have its fiber undergo a prolonged stay in total immersion in water,

- remove the fiber from the water,

- weigh the fiber again to determine its final weight (Pf),

The difference between the final weight (Pf) and the initial weight (Pi) makes it possible to determine the weight of water inside the pores. The pore volume is determined knowing that 1 g of water is equivalent to a volume of 1 cm ³ . The value of the porosity (p) follows from formula (1) below:

P = (Vpores / Vtoial) x 1Q0 (1) where Vpores is the total volume of all the pores and Vtotai is the volume of the fiber. When fibers having the desired porosity have been chosen, they must be immersed in resin baths (4a, 4b). The strands (1a, 1b) of these fibers can be impregnated and resin-coated using a single bath ( 4a, 4b) if only one color is desired. Next Desired decorations, they can however be impregnated with resin of different colors. In Figure 1, two strands (1a, 1b) are shown. A strand (1a) can go for example in a bath of resin (4a) brown while the second strand (1b) is bathed in a bath of resin (4b) white. In this case, the combination of brown and white colors makes it possible to create decorations with the appearance of wood. This characteristic is particularly interesting for the manufacture of furniture or garden decorations.

In Figure 1, before the immersion phase, the strands (1a, 1b) are wound to prevent their entanglement. They can be wound simply, using a roller (7a, 7b) or any other delivery system. This system may be equipped with a device for adjusting the feed speed of the strands (1a, 1b) and therefore the time they will spend at the immersion station (10a, 10b). - 6 - fibers of flax, hemp, cotton, sea rush, coconut, paimier, rattan or banana. The fibers of inorganic origin may, for example, be selected from the fibers of crystal, silica, basalt or carbon. Finally, the fibers of animal origin may for example be woolen or silk fibers.

The chosen fibers can be of variable size thus making it possible to adapt to the type of element that one wants to create. They have a length that can vary between 1 m and 5 kms. Once the choice of the type of fibers to be used has been made, the desired values concerning their density as well as their linear density should be chosen. The density of the fibers being directly correlated to their porosity, it is a question of choosing fibers having preferentially a density of less than 2 g / cm 3 and a linear density of between 400 g / km and 2400 g / km.

A preferred step of the process consists in selecting fibers of a given porosity. The Applicant has surprisingly found that better results were obtained by choosing a porosity greater than 20%. The fibers then have a larger amount of pores that allow better absorption of the resin. There are many methods to measure porosity. S! There are direct methods of determination such as:

- tomography,

- radiography,

- or the micrograph on cut pieces,

but also indirect methods, for example:

- density measurement,

- or weighing.

Among these indirect methods, the so-called conventional immersion technique has been preferred, it is easily applicable and is known to those skilled in the art. It consists of different stages consisting of: The immersion baths (4a, 4b) may be simple trays made of aluminum, plastic or other rigid material. They may however be in the form of more complex devices (10a, 10b) comprising means such as pulleys (8a, 8b) or winches for advancing the strand (1a, 1b) at a given speed. (10a, 10b) makes it possible to obtain strands (1a, 1b) impregnated and coated with resin in a uniform and constant manner.

The step of immersing the fibers with the resin does not require a specific duration but preferably has a duration of less than 5 minutes and between 1 and 20 seconds.

The resin baths (4a, 4b) can also be equipped with temperature regulators to maintain the constant temperature. This feature makes it possible to keep its viscosity of the resin constant and thus to allow a more uniform impregnation and coating. They may, for example, be maintained at a temperature above 35 ° C. This makes it possible to reduce the viscosity of the resins and thus to promote their absorption by the fibers (1a, 1b) during their passage through the immersion station.

Two distinct phenomena occur during the transition to the immersion station: impregnation and coating. While the impregnation phase consists in filling the pores present in the fibers with resin, the coating phase is similar to the state of the art in that it consists only in obtaining a layer of resin that is more or less fine. on the outer part of the fiber.

The next step consists in wiping each strand (1a, 1b) after passing through the resin bath (4a, 4b). It consists in removing the excess resin present on the strands (1a, 1b) at their outlet from the bath (4a, 4b). The means (5a, 5b) used during this step can be in various forms. It can be a scraper that grips the strand (1a, 1b) and thus remove the surplus of resin or any other different technique, such as a cylinder type wiper in which there is a flexible material for wiping the excess resin when the strand (1 a, 1 b) is passed in the hollow part said cylinder, said hollow portion having a diameter similar to that of the strand. In the same way, the scraper may also consist of a plate having a conical hole in which is inserted the strand to be wiped.

In addition to avoiding excess resin and thus serving as a calibration measure for coating the strands (1 a, 1 b), the wiping step also makes it possible to optimize the quantities of resin used by redeposing the excess in the bath so that it can be reused. The resin can directly fall back into the immersion station (10a, 10b), or it can have a different tank corresponding to the recovery station (1 1 a, 1 1 b). In this case, a filter for removing impurities from the resin may exist between the recovery station (11a, 11b) and the immersion station (10a, 10b).

In addition, the passage through the wiping station (5a, 5b) improves the efficiency of the impregnation phase by forcing the penetration of the resin to the core of the fibers.

The next step is to join the strands (1a, 1b) into a single beam (2). Once they are out of the resin baths (4a, 4b) and wiped, as explained above, they are grouped into bundles (2) thanks to a low pressure operated by a grouping station (9). This grouping station (9) can be an operator manually exerting pressure but also an automatic device (9) for exerting a constant pressure at the outlet of the resin baths (4a, 4b). This device (9) may for example be in the form of two parallel plates (51, 52) exerting opposing vertical movements of bringing them closer to each other. In the same manner as for the cylinder described above, the distance (53) between the two piaces (51, 52) must be similar or smaller than the diameter of the strand (1 a, 1 b) so that pressure can be exerted. During this step, the presence of resin will allow the strands (1a, 1b) to remain glued to each other and thus give the desired decorative effect. In the preceding example, the mixture of the two colors, white and brown, in one and the same beam (2) makes it possible to accentuate His resemblance of the volume or surface element with a wooden element.

The following step is the formation of the desired surface or volume element by means of a tensioning device (3) such as that described in FIG. 2. During this step, the bundle (2) of fibers created in the preceding steps is wrapped around this device (3). Its shape may vary according to the element to be formed. It can be two-dimensional (2D), such as a circle, a square or a diamond, or three-dimensional (3D), such as a sphere, a cylinder or a cube. The device (3) has return points (6) for winding the bundles (2) of fibers and can be in the form of removable or fixed plugs.

The bundle (2) of fibers is first wound on one of the return points (6) of the device (3). It is then returned to another point (8) while applying a regular and constant tensile tension. This step is repeated successively on several points of reference (6) opposite, The order of succession of the return points (6) depends on the chosen decoration and the desired effect. To form a sphere, two tensioning devices (3) such as that shown in Figure 2 are used. The first device (3) is first used by winding the beam (2) on one of its return points (8) and then the second return point (6) is selected on the second tensioning device (3). The step of winding and returning the beam (2) to a succession of return points (6) is repeated until the desired pattern is obtained on the sphere. These devices (3) can be of variable sizes. For example, in the case of the device (3) shown in FIG. 2, the diameter of its sphere may vary from 20 cm to 3 m. Depending on the type of element formed and the desired effect, the method may comprise an additional step of forming a peripheral bead to improve its finish of the element after the winding of the bundle (2) around the tensioning device ( 3). This solid and closed peripheral bead is placed at the edges or edges of the surface and geometric elements, by bringing the bundle (2) of fibers several times helically around successive return points (6) aligned on the same line,

Finally, and preferably immediately after the structure has been completed, a step of curing the resin is performed. This can be done in the open, using a hot air stream or under heat radiation from a light source, infrared or ultraviolet. After this step, the hardened resin makes it possible to obtain very strong and ready-to-use elements.

The arrangement of the various elements and / or means and / or steps of the invention, in the embodiments described above, should not be understood as requiring such an arrangement in all implementations. In any case, it will be understood that various modifications may be made to these elements and / or means and / or steps, without departing from the spirit and scope of the invention. In particular :

the length of the fibers used,

- the duration of passage to the immersion station (10),

the number of strands (1a, 1b) included in a bundle (2),

the color of the resin baths (4a, 4b),

the shape of the tensioning devices (3),

- the type of device used in the fitting room (5a, 5b),

- the presence or absence of a recovery station (1 a, 11 b).

Claims

A method of manufacturing a surface or optical object from bundles of fibers and resin, said method comprising steps of:

- form at least two strands of fibers,

resin coating these fiber strands by passing each of them in a separate immersion bath, these baths containing resin of different colors and decorative pigments,

- wipe the resin-coated strands and join them into a single bundle of fibers,

characterized in that it consists, beforehand, in selecting porous fibers, and in that it consists in simultaneously making a coating and an impregnation of the fiber to form, in fine, a bundle of reinforced fibers, and more precisely a bundle of resin reinforced by fibers which are themselves armed with resin.

2. Method according to claim 1, of choosing fibers whose porosity is greater than 20%.

3. Method according to one of claims 1 or 2, of choosing fibers having a density of less than 2 g / cm ³ and having a linear density of between 400 g / km and 2400 g / km.

4. Method according to claim 3, of choosing fibers having a linear density of between 400 g / km and 800 g / km. 5, Process according to claim 3, of choosing fibers having a linear density of between 600 g / km and 2400 g / km. 6. Method according to one of claims 1 to 5, wherein the fibers are fibers of plant origin selected from the following family: flax fibers, hemp fibers, cotton fibers, sea bean fibers, coconut fibers , palm fiber, rattan fiber, banana fiber. 7. A method according to one of claims 1 to 5, wherein the fibers are fibers of inorganic origin selected from the following family: crystal fibers, silica fibers, basalt fibers, carbon fibers.

8. A method according to one of claims 1 to 5, wherein the fibers are animal fibers selected from the following family: wool fibers, silk fibers.

9. Method according to one of the preceding claims, wherein during the impregnation phase, the resin baths are maintained at a temperature above 35 ° C.

10. Method according to one of the preceding claims, wherein during the impregnation phase, the fiber strands are left in the resin baths between 1 second and 20 seconds.

1 1. Method according to one of the preceding claims, wherein the wiping step is to pass the strands through a scraper so as to force the penetration of the resin to the heart of the fibers. 12. A product or article of furniture and / or decoration comprising at least one surface constituted by a network of bundles of resin fibers, characterized in that it comprises fibers having a porosity of at least 20%, which fibers are reinforced by the resin which fills the pores.