EP3650613A1 - Method for producing a joint between two strips of a resilient floor covering - Google Patents

Abstract

The invention relates to a method for producing an assembly joint 40 between two strips of plastic material 10a, 10 intended for producing a floor covering, comprising: • an upper surface 11a, 11b; and • a lower surface; and • said upper surfaces 11a, 11bet lower being connected by at least one side, at least a portion of the length of which is intended to receive said assembly joint40, said portion being called assembly edge; and • said two bands 10a, 10bétant positioned so that each of their assembly edges are located opposite one with the other, with a distance separating these two assembly edges defining a clearanceJ. invention, the method successively comprises: - a step of injecting a photoactivatable material between said two strips 10a, 10b; and a step of activating said photoactivatable material carried out by exposing it to radiation comprising at least one ultraviolet ray30.

Description

FIELD OF THE INVENTION

The present invention relates to a method of producing an assembly joint between two strips of plastic material intended for producing a floor covering.

More specifically, the present invention relates to a method for joining two bands of resilient plastic material, preferably composed of PVC but also of linoleum, polyolefin, or rubber.

PRIOR ART

• une surface supérieure formant la surface fonctionnelle dudit revêtement de sol, et
• une surface inférieure destinée à être en contact avec le sol à recouvrir,
• lesdites surfaces supérieure et inférieure étant reliées par au moins un côté, dont au moins une portion de la longueur dudit côté est destinée à recevoir ledit joint d'assemblage, ladite portion étant appelée bord d'assemblage.

A method is known for producing an assembly joint between two strips of plastic material intended for producing a floor covering, each of the two strips having a shape of strip, strip or slab and comprising:

• an upper surface forming the functional surface of said floor covering, and
• a lower surface intended to be in contact with the ground to be covered,
• said upper and lower surfaces being connected by at least one side, at least a portion of the length of said side is intended to receive said assembly joint, said portion being called assembly edge.

When making the assembly joint, the two strips are placed on the floor to be covered and positioned so that each of their assembly edges are located opposite one another, with a distance separating these two assembly edges defining a clearance J, and so that the upper surfaces of the two strips at the right of the assembly edge are located in the same plane.

One of the most used methods of producing an assembly joint between two strips of plastic intended for producing a floor covering is cold welding, also called cold treatment or chemical welding.

This process consists in injecting a liquid resin composed of PVC and a solvent of PVC, such as for example tetrahydrofuran (THF), between the two strips to be joined then to simply leave to dry to form the joint, all the steps of this type of process taking place at room temperature.

Cold welding processes are usually used to join two strips of floor covering intended for light traffic use because the resulting mechanical strength is limited. Preferably, cold welding is intended for flooring of residential buildings, and is prohibited for the production of sports floors, as well as in areas in a humid atmosphere or with a frequent presence of water on the ground.

• La résine contient des solvants organiques tels que le THF, qui sont des produits irritables, voire dangereux pour la santé des utilisateurs en raison de leur caractère cancérigène ou mutagène ;
• En raison de la faible viscosité des résines liquides utilisables, cette méthode permet uniquement de réaliser des soudures à plat, et n'autorise donc pas la remontée de la soudure sur une plinthe par exemple ;
• Le délai de séchage est long et compris entre 2h et 4h.

This type of welding has many drawbacks:

• The resin contains organic solvents such as THF, which are irritable products, even dangerous for the health of the users because of their carcinogenic or mutagenic character;
• Due to the low viscosity of the liquid resins which can be used, this method only allows flat welds to be made, and therefore does not allow the solder to rise up on a plinth for example;
• The drying time is long and between 2h and 4h.

Another known method for producing an assembly joint between two strips of plastic material intended for producing a floor covering is hot welding.

It is particularly recommended to join strips of a floor covering intended for a use with strong request, for example by a heavy traffic, or also for floors of sports grounds. This process is suitable for producing floor coverings for rooms in a humid atmosphere or with frequent presence of water on the floor, since the joint produced between two strips is completely waterproof and prevents any infiltration of water under the floor covering.

Regardless of the destination of said floor, this method is also used when said joint is positioned transversely to the direction of travel on the floor.

The hot welding method has three stages of production.

Initially, the edges connecting the outer surface and the assembly edge of the plastic strips are chamfered in order to open the space between the strips in order to increase the contact surface of the assembly edge, to improve the mechanical strength of the joint, and to facilitate penetration of the joint between the two strips.

Then, in a second step, a plastic bead is unwound through a nozzle which heats it continuously, then is introduced into the space intended to receive the seal. Thus, the material of the bead fuses with the material of the strips and therefore makes it possible to form the joint.

Thirdly, once the joint is formed, a leveling step makes it possible to flatten the joint by mechanically removing its overhanging upper part, so that the surface of the joint is located in the same plane as the surface of the flooring.

Hot welding is a long process and requires a great deal of expertise from the installer. It must indeed perfectly control the speed of unwinding of the cord, the heat emitted by the device and the pressure exerted, in addition to the steps for producing the chamfers and leveling. This technique has the disadvantage of requiring the training of installers to obtain a satisfactory result.

Also, this type of weld forms a fairly wide joint, of the order of 4 or 5 mm, which marks a visual break in the decorative pattern of the exterior surface of said floor covering, which has a drawback. In addition, this widely visible joint has the characteristic of clogging during its service life, because its external surface is composed entirely of raw plastic material, unlike the floor covering which is very often covered, in the factory, with a protective varnish.

Additionally, hot welding poses risks to the health of the installer. Heating the cord causes smoke to be released into the atmosphere and implies the presence of a strong heat source, around 180 ° C at the nozzle outlet.

Finally, hot welding is very complex to implement for the production of non-rectilinear joints, or to join two strips of small thickness or whose material comprises deep grains.

STATEMENT OF THE INVENTION

The technical problem which the invention proposes to solve is therefore to propose a method for producing a joint between two strips of plastic material for producing a floor covering, making it possible to avoid water infiltration between the two strips by total sealing, ensuring continuity of the decorative appearance of said coating, while improving its implementation by installers compared to the prior art, and increasing its care and maintenance properties.

• une surface supérieure formant la surface fonctionnelle dudit revêtement de sol, et
• une surface inférieure destinée à être en contact avec le sol à recouvrir,
• lesdites surfaces supérieure et inférieure étant reliées par au moins un côté, dont au moins une portion de la longueur dudit côté est destinée à recevoir ledit joint d'assemblage, ladite portion étant appelée bord d'assemblage,
• lesdites deux bandes étant disposées sur le sol à recouvrir et positionnées de telle sorte que chacun de leurs bords d'assemblage soient situés en regard l'un par rapport à l'autre, avec une distance séparant ces deux bords d'assemblage définissant un jeu J.

The present invention proposes to solve this technical problem by a method of producing an assembly joint between two strips of plastic material intended for producing a floor covering, each of said two strips having the shape of a strip, of strip. or slab and comprising:

• an upper surface forming the functional surface of said floor covering, and
• a lower surface intended to be in contact with the ground to be covered,
• said upper and lower surfaces being connected by at least one side, at least a portion of the length of which side is intended to receive said assembly joint, said portion being called assembly edge,
• said two strips being arranged on the ground to be covered and positioned so that each of their assembly edges are located opposite one another, with a distance separating these two assembly edges defining a clearance J.

• une étape d'injection d'une matière photoactivable entre les deux bords d'assemblage, de sorte à remplir l'espace formé par le jeu J entre lesdites deux bandes,
• une étape d'activation de ladite matière photoactivable effectuée en l'exposant à un rayonnement comprenant au moins un rayon ultraviolet.

This process is characterized in that it successively comprises:

• a step of injecting a photoactivatable material between the two assembly edges, so as to fill the space formed by the clearance J between said two strips,
• a step of activating said photoactivatable material carried out by exposing it to radiation comprising at least one ultraviolet ray.

From the above, ultraviolet radiation makes it possible to activate the binding power of the photoactivable material and to assemble the two bands together.

In a preferred embodiment, the clearance J has a value of less than 2 mm, advantageously less than 1 mm.

According to a preferred embodiment, the photoactivatable material contains an acrylate. For example, the photoactivatable material contains a urethane acrylate, a cyanoacrylate or an isobornyl acrylate.

According to a preferred embodiment, the photoactivatable material is based on silicone or epoxy.

In a particular embodiment, a step of leveling the joint follows the activation step, during which any surplus of photoactivatable material is eliminated, so as to obtain continuity between the upper surfaces of said two strips.

In another particular embodiment, a step of cutting the assembly edges is carried out before the injection step, so as to improve the straightness of said assembly edges.

• déroulé puis collé en chevauchement sur les surfaces supérieures desdites deux bandes, avec la direction de déroulement du ruban de protection qui suit les bords d'assemblage, et
• fendu dans sa longueur entre les deux bords d'assemblage pour permettre l'injection de la matière photoactivable.

According to a particular embodiment, a protection step immediately precedes the injection step, during which a protective tape is successively:

• unrolled then glued overlapped on the upper surfaces of said two strips, with the direction of unwinding of the protective tape which follows the assembly edges, and
• split lengthwise between the two assembly edges to allow injection of the photoactivatable material.

In an additional embodiment, a covering step is carried out between the injection step and the photoactivation step, comprising the laying of a film transparent to ultraviolet rays at the interface between the photoactivatable material and the air. ambient, thereby isolating the photoactivatable material from the ambient air.

According to different embodiments, the step of activating the photoactivatable material consists of a polymerization or a crosslinking.

In another embodiment, the photoactivatable material is also exposed to a humid atmosphere to complete crosslinking or polymerization. This can advantageously be the case when the photoactivatable material also activates on contact with a humid atmosphere, in particular in the case of cyanoacrylates or silicones.

In another additional embodiment, the radiation to which the photoactivatable material is exposed also includes at least one ray having a wavelength visible to the human eye. This can advantageously be the case when the photoactivatable material also activates under this visible wavelength.

Advantageously, the photoactivatable material is an adhesive, a resin or a varnish, preferably mono-component, and preferably without solvent.

The invention and the advantages which ensue from it emerge clearly from the above description. We note in particular the tightness of the joint thus produced, making it possible to join the two assembly edges. The low value of clearance J compared to the prior art also makes it possible to obtain the visual continuity sought in the aesthetic appearance of said floor covering. The surface properties of the joint once crosslinked are similar to those of said coating.

SUMMARY DESCRIPTION OF FIGURES

• la figure 1 est une vue en coupe du revêtement de sol avant l'étape d'injection ;
• la figure 2 est une vue en coupe du revêtement de sol de la figure 1 après l'étape d'injection ;
• la figure 3 est une vue en coupe du revêtement de sol de la figure 1 lors de l'étape d'activation ;
• la figure 4 est une vue en coupe du revêtement de sol de la figure 1 après l'étape de protection.

The manner of carrying out the invention as well as the advantages which result therefrom will emerge clearly from the description of the embodiment which follows, given by way of indication but not limitation, in support of the appended figures in which:

• the figure 1 is a sectional view of the floor covering before the injection step;
• the figure 2 is a sectional view of the floor covering of the figure 1 after the injection step;
• the figure 3 is a sectional view of the floor covering of the figure 1 during the activation step;
• the figure 4 is a sectional view of the floor covering of the figure 1 after the protection step.

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to a method of producing an assembly joint 40 between two strips of plastic material 10a, 10b intended for producing a floor covering.

The material making up said strips 10a, 10b is preferably a polyvinyl chloride (PVC), but may also be a linoleum, a polyolefin or else a rubber.

The figure 1 illustrates the arrangement of said two bands 10a, 10b, for the implementation of the method which is the subject of the invention.

Each of said strips 10a, 10b has the form of a panel, a strip or a slab, for example presented in a roll, and comprises an upper surface 11a, 11b forming the functional surface of said floor covering, and a lower surface 12a, 12b intended for be in contact with the support S to be covered.

Advantageously, each of the strips 10a, 10b has a thickness between 1 and 15 millimeters, preferably between 2 and 10 millimeters.

The upper surfaces 11a, 11b and lower 12a, 12b are connected by at least one side 13a, 13b, at least a portion of the length of said side is intended to receive said assembly joint 40. This portion of said side is called edge assembly 14a, 14b. The intersection of the upper surface 11a and the assembly edge 14a defines an assembly edge 15a. Similarly, the intersection of the upper surface 11b and the assembly edge 14b defines an assembly edge 15b.

The two strips 10a, 10b are arranged on the support S to be covered, and positioned so that each of their assembly edges 14a, 14b are located opposite one with respect to to the other. A preferentially regular distance between these two assembly edges 13a, 13b is arranged, thus defining a clearance J. Preferably, the clearance J has a value less than 2mm, advantageously less than 1mm.

The low value of the clearance J makes it possible to improve the visual rendering of said floor covering, by eliminating the break effect in the pattern of said floor covering.

According to a preferred embodiment of the invention, a first injection step is carried out. As the figure 2 , it consists in injecting a photoactivatable material 20 so as to fill the space defined by the clearance J and the support S to be covered.

The photoactivatable material 20 has the capacity to activate its binding power under the effect of radiation comprising at least one ultraviolet ray 30. The radiation can be composed of 100% ultraviolet rays, or can comprise ultraviolet rays and rays with wavelengths visible to the human eye. The photoactivatable material can also be activated by a humid atmosphere. Preferably, this photoactivatable material 20 belongs to the family of acrylates, advantageously being based on urethane acrylate, cyanoacrylate or isobornyl acrylate, but can also be based on silicone or epoxy.

According to different embodiments, said activation step consists in a polymerization or in a crosslinking of said photoactivatable material 20. The photoactivatable material 20 is for example an adhesive, a resin or a varnish, preferably mono-component, and preferably solvent-free.

An activation step shown on the figure 3 follows the injection step. It consists in exposing the photoactivatable material 20 to at least ultraviolet radiation 30 coming from an ultraviolet source 31. Under the effect of this ultraviolet radiation 30, the molecules composing the photoactivable material 20 solidify and form the joint of assembly 40.

Advantageously, the source of ultraviolet 31 moves relative to the two strips 10a, 10b in the direction of the assembly edges 14a, 14b at a speed preferably understood. between 0.1 to 20 m / min, and preferably from 1 to 10 m / min. The ultraviolet source 31 delivers ultraviolet rays having a wavelength ranging from 200 to 500 nanometers, preferably between 300 and 450 nanometers, at a power advantageously between 10mW / cm ² and 10W / cm ² , preferably between 50mW / cm ² and 4W / cm ² . In addition, the distance between the ultraviolet source 31 and the assembly joint 40 is preferably less than 1 meter, preferably at 50 centimeters or even in contact with the assembly joint 40.

The activation step therefore avoids, on the one hand the emission into the atmosphere of toxic compounds, and on the other hand the use of strong sources of heat.

Thus, as the space between said two assembly edges 14a, 14b has been filled by the injection of said photoactivatable material 20 during the injection step, said assembly joint 40 makes it possible to ensure the waterproofing of said floor covering.

Advantageously, a step of leveling the seal 40 follows the activation step. This leveling step is intended to remove any excess material from the joint 40 which protrudes from the surface of said floor covering. It consists in obtaining a smooth surface 41 of said joint 40 using a cutting tool, said smooth surface 41 being plane between said two assembly edges 15a, 15b.

This leveling step of said seal 40 therefore makes it possible, if necessary, to remove any roughness and defects which could have appeared during the previous injection and activation steps, by obtaining a smooth surface 41 which is easy to maintain throughout the lifetime of said floor covering.

Advantageously, a step of cutting said assembly edges 14a, 14b can take place before the injection step. It consists in improving the surface condition and the flatness of said assembly edges 14a, 14b using a cutting tool. This recutting step is preferably implemented to facilitate the following steps of said method, more particularly the injection step.

Advantageously, as illustrated on the figure 4 , a protection step immediately precedes the injection step, during which a protective tape 50 is successively unrolled and then stuck overlapped on said upper surfaces 11a, 11b, the direction of unwinding of the protective adhesive 50 follows said assembly edges 15a, 15b.

Finally, said protective tape 50 is split in its length between said two assembly edges 15a, 15b thus creating an injection slot 51. This injection slot 51 is necessary in order to be able to inject said photoactivatable material 20 through the tape protection 50 during the injection step.

Advantageously, a recovery step is interposed between the injection and activation steps. This step allows the installation of a film transparent to ultraviolet rays, and possibly to useful visible rays which would compose the radiation, at the interface between the photoactivatable material 20 and the ambient air, thus making it possible to isolate the photoactivable material 20 from Ambiant air.

This recovery step finds a particularly advantageous application when it is necessary to perform the activation step in the absence of oxygen, due to the nature of said photoactivatable 20 material used.

The method which is the subject of the invention therefore makes it possible to produce an assembly joint 40 between two strips of plastic material 10a, 10b intended for producing a floor covering. This process is simple to implement, and does not release toxic products into the atmosphere. In addition, it avoids the use of an important source of heat.

Also, the seal 40 thus obtained ensures a seal between said strips of plastic material 10a, 10b, and its fineness makes it possible to obtain a satisfactory visual result.

The assembly joint 40 therefore makes it possible to mechanically link the two strips 10a, 10b so as to make them integral with one another by forming said floor covering. This mechanical connection meets the European standards for the coatings considered. For example, the mechanical bond obtained on compact heterogeneous PVC floors conforming to European standard EN 10582 and also for PVC floors on foam for European standard EN 651 in terms of mechanical strength, and in particular withstands a higher tensile force. at 240N / 50mm according to a test carried out in accordance with the test standard EN 684 of February 1996.

By way of example, such a floor covering assembly joint produced with the process which is the subject of the invention using, on the one hand, two strips of plastic material sold by the Applicant under the reference “Taralay premium compact 43 Neopolis ”, namely a heterogeneous compact PVC floor according to European standard EN 10582 with a thickness of 2 mm, and using, on the other hand, a photopolymerizable adhesive based on acrylate, has a mechanical strength of 665N / 50mm. Thus, the process which is the subject of the invention makes it possible to obtain a joint having mechanical strength meeting the requirements of European standards EN 10582 governing the mechanical resistance of floor coverings.

As a further example, such a floor covering assembly joint produced with the process which is the subject of the invention using, on the one hand, two strips of plastic material sold by the Applicant under the reference "MIPOLAM ACCORD" , namely a homogeneous PVC floor according to European standard EN10581, 2 mm thick, and using, on the other hand, a photopolymerizable adhesive based on acrylate, has a mechanical strength of 440N / 50mm. Thus, the process which is the subject of the invention makes it possible to obtain a joint having mechanical strength meeting the requirements of European standards EN10581 governing the mechanical resistance of floor coverings.

Claims (10)

Process for producing an assembly joint 40 between two strips of plastic material 10a, 10b intended for producing a floor covering, each of said two strips 10a, 10b having a shape of a strip or slab and comprising: • an upper surface 11a, 11b forming the functional surface of said floor covering; and • a lower surface 12a, 12b intended to be in contact with the support to be covered; and • said upper surfaces 11a, 11b and lower 12a, 12b being connected by at least one side 13a, 13b, at least a portion of the length of which side is intended to receive said assembly joint, said portion being called edge of assembly 14a, 14b ; and • said two strips 10a, 10b being arranged on the surface S to be covered and positioned so that each of their assembly edges 14a, 14b are located opposite one another, with a distance separating these two assembly edges 14a, 14b defining a clearance J ; the method being characterized in that it successively comprises: a step of injecting a photoactivatable material 20 between the two assembly edges 14a, 14b, so as to fill the space formed by the clearance J between said two strips 10a, 10b; and a step of activating said photoactivatable material 20 carried out by exposing it to radiation comprising at least one ultraviolet ray 30. A method according to claim 1 characterized in that the photoactivatable material 20 contains an acrylate, an epoxy or a silicone. Method according to one of claims 1 to 2 characterized in that a leveling step of the joint 40 follows the activation step, during which any surplus of photoactivatable material 20 is eliminated, so as to obtain continuity between the upper surfaces 11a, 11b of said two strips 10a , 10b . A method according to claim 1 to 3 characterized in that a step of cutting the joining edges 14a, 14b is carried out before the injection step, so as to improve the straightness of said joining edges 14a, 14b. Method according to one of Claims 1 to 4, characterized in that a protection step immediately precedes the injection step, during which a protective tape 50 is successively unwound and then stuck overlapped on the upper surfaces 11a, 11b of said two strips 10a, 10b, the direction of unwinding of the protective tape 50 along the assembly edges 14a, 14b, and finally split in its length between the two assembly edges 14a, 14b so as to create a slot 51 allowing the injection of the photoactivatable material 20. Method according to one of Claims 1 to 5, characterized in that a covering step is carried out between the injection step and the activation step, comprising the laying of a film transparent to ultraviolet rays 30 to 1 interface between the photoactivatable material 20 and the ambient air, thus making it possible to isolate the photoactivatable material 20 from the ambient air. Method according to one of claims 1 to 6 characterized in that the step of activating said photoactivatable material 20 is a polymerization, or a crosslinking. A method according to claim 7 characterized in that the photoactivatable material also polymerizes or crosslinks in contact with a humid atmosphere. Method according to one of Claims 1 to 8, characterized in that the radiation to which the photoactivatable material is exposed also comprises at least one ray having a wavelength visible to the human eye. Method according to one of claims 1 to 9 characterized in that the photoactivatable material 20 is an adhesive, a resin, or a varnish, without solvent.

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