EP3784861A1

EP3784861A1 - Arthropod protector screen and production method thereof

Info

Publication number: EP3784861A1
Application number: EP19726064.9A
Authority: EP
Inventors: François CAPITAINE; Nathalie GAUDUCHOU CAPITAINE
Original assignee: Gocap
Current assignee: Gocap
Priority date: 2018-04-24
Filing date: 2019-04-24
Publication date: 2021-03-03
Also published as: MA52358A; WO2019207250A1; FR3080405B1; FR3080405A1; US20220003040A1

Abstract

The present invention relates to a protector screen for use against arthropods, comprising a sheet (11) having a core made from glass or a plastic material, which is at least partially transparent, and comprising a plurality of ventilation holes (12), each of said ventilation holes being designed to prevent arthropods from passing therethrough. At least a portion of each ventilation hole is closed by a lateral wall or by contiguous lateral walls forming a single piece that is open at the ends thereof. The ventilation holes (12) are designed such that a gaseous fluid, such as air, can pass through the screen (10), while optimising light transmission and optionally cooling the fluid passing through the screen.

Description

Screen for protection against arthropods and its method of manufacture

BACKGROUND OF THE INVENTION

Field of the invention

The present invention relates to a shield for preventing the passage of arthropods, including insects and spiders, to isolate a building such as a dwelling or a building, a greenhouse to protect a crop, or a vehicle for transporting at least one human and / or animal, while allowing sufficient ventilation.

It also relates to a method of manufacturing such a protective screen.

Technological background

The use of mosquito nets has long been known to control the intrusion of insects, including mosquitoes and / or flies, into a dwelling.

These mosquito nets are used to seal the openings and form a barrier to insects while allowing a good air exchange.

The mosquito nets available today are typically made by weaving with a simple cross warp and perpendicular weft warp threads, which is perpendicular.

Meshes of these mosquito nets define openings typically having dimensions of between 1 and 2 mm, to prevent the passage of insects while providing good ventilation. However, it is observed that these mosquito nets have a poor behavior over time with a more or less rapid alteration of at least some of their openings, for example following a slip of the son, a hitch, repeated friction, stretching, or to a fraying related to a cut of the mosquito net, ...

This structural degradation of the mosquito net reduces its effectiveness and can give free rein to insects.

Moreover, it can be seen that the weaving methods generally used can not guarantee a regular base mesh so that even new mosquito nets can have openings having variable dimensions.

However, a slight variation in the dimensions of an opening may allow the passage of an insect, including the aedes albopictus, also called tiger mosquito, which has small dimensions.

However, the latter is well known to be the main vector of various viral diseases, such as dengue, chikungunya, zika or yellow fever.

Another type of mosquito, the anopheles, may be a major carrier of the malaria parasite, particularly dangerous for a newborn, a child or a pregnant woman with a weakened immune system. This disease, which mainly affects Asia, South America and Africa, weighs heavily on the resources of the affected countries and on the populations concerned.

To increase the effectiveness of mosquito nets, it was proposed in the 1980s to pre-impregnate them with insecticide.

The World Health Organization (WHO) recommends widespread access to these pre-impregnated mosquito nets in endemic areas, particularly malaria.

Long-lasting insecticidal nets (LLINs) currently recommended are treated with pyrethroids. However, their massive use in recent years has resulted in an increase in the selection of mosquito resistance to these insecticides.

Be that as it may, it is found that mosquito nets with or without chemical additives have a low resistance to tearing, which in fact decreases their lifespan. The WHO estimates that about half of the nets in place are holed, or more generally ineffective after a few days of use.

In addition, the pre-impregnation of mosquito nets does not answer all the problems observed:

- the use of chemicals is likely to cause irritation to some users, and there are problems of waste at the end of life of the products to be treated,

- the life expectancy of the insecticide is estimated on average to a few months because it is not resistant to repeated washing (WHO 2008 report),

- Resistance to insecticides used have developed in recent years ("Mosquito nets impregnated and mosquito resistance to insecticides", Frédéric Darriet, IRD editions, Collection: didactics, 2007, and Mark Roland 2007), which can have health consequences seriously affected populations.

In addition, and more generally, it is observed that mosquito nets, currently on the market, have low transparency and therefore reduce the field of vision, or, at best, cause visual disturbances.

This is particularly the case of metal screens, which have good mechanical strength, but offer very poor transparency.

There is therefore a pressing need for a shield against arthropods, whose original design overcomes the disadvantages of the prior art described above.

Object of the invention

The present invention aims to overcome the drawbacks of the prior art by providing a shield against arthropods, simple in its design and its operating mode, forming a real mechanical barrier to the passage of these arthropods, without insecticide, having excellent durability, while ensuring adequate air exchange through it.

An object of the present invention is such a shield providing a high transparency and, for example, likely to replace a clear glass in a glazing. Another object of the present invention is such a shield, the original shape of its ventilation openings ensures a maximized air exchange through this screen while preventing the passage of arthropods.

Yet another object of the present invention is such a shield having increased light transmission to ensure good visualization therethrough.

The present invention also relates to a method of manufacturing such a shield against arthropods.

BRIEF DESCRIPTION OF THE INVENTION

For this purpose, the invention relates to a shield against arthropods, such as insects, cockroaches and spiders, comprising

a sheet comprising a core of glass or of plastics material, said sheet being at least partly transparent and comprising a plurality of ventilation holes,

each of said aeration holes being configured to prevent the passage of arthropods therethrough,

said aeration holes being intended to ensure the passage of a gaseous fluid through this screen, said sheet having two faces. According to the invention, at least one of the portions opening on said faces of at least some of said ventilation holes has an elongate cross section, said section comprising a longitudinal axis and a transverse axis, the dimension of each said portions along the longitudinal axis being greater than the largest dimension of the arthropods against which this shield provides protection, the dimension of each portion along the transverse axis being less than or equal to the largest dimension of the main body of these arthropods against which this screen provides protection, this main body excluding the head and appendages of the corresponding arthropods.

Thus, this sheet forming the protection screen typically has two faces and a peripheral edge, ventilation holes passing through the thickness of this sheet so that their free ends open on these two faces, an air passage is assured through this sheet.

For at least some of the ventilation holes of this sheet, at least one free end of these ventilation holes thus has a section transverse line, for example in the plane formed by the corresponding face, of elongated shape such as oblong, elliptical or oval. This elongate cross section thus comprises a longitudinal axis and a transverse axis, its dimension along the longitudinal axis being greater than the largest dimension of arthropods against which this screen provides protection, the dimension along the axis transversal being less than or equal to the largest dimension of the main body of these arthropods against which this screen provides protection, this main body excluding the head and appendages of the corresponding arthropods.

The term "appendix", for example a locomotor appendix such as a paw arthropod.

It is thus observed that the shield of the invention ensures maximization of air exchange through the sheet while preventing the passage of arthropods, or by forming an impassable mechanical barrier for arthropods against which it is intended to provide protection.

Advantageously, the two free ends of at least some of the ventilation holes of this sheet have such a right cross section without necessarily being identical. The screen does not have any particular editing direction.

In general, the portion of these ventilation holes located between these two free ends, and therefore in the thickness of the sheet, can be any, for example of constant section or on the contrary, of flared shape such as conical and / or present a narrowing.

Each ventilation hole of this protective screen is at least partly delimited laterally by a lateral wall or by a belt of side walls, closed, open at its ends and in one piece, or in one piece, which belongs to said sheet. Advantageously, this side wall, or this belt of side walls, closed laterally delimiting at least a portion of the corresponding hole, not resulting from an assembly, or binding, son as obtained by weaving or knitting with the mosquito nets of the state of the art, it has excellent mechanical strength over time. Each opening is thus not susceptible to deformation, or variation in its dimensions, over time, except to achieve a deliberate degradation of the corresponding opening. By way of example, since the sheet consists solely of said glass or plastic core, the lateral wall or the lateral wall belt laterally delimiting each of the ventilation holes forms with the remainder of this sheet a monolithic structure.

In other words, and more generally, for each of said ventilation holes, the lateral wall or the lateral wall belt laterally delimiting at least the part of the corresponding ventilation hole, at the level of said core, forms with the latter a single unit, or monolithic structure.

These ventilation holes may be identical or at least some of them have different dimensions and / or shapes while being configured to prevent the passage of arthropods.

The variations in the dimensions of the ventilation holes from one protective screen to another may, for example, be a function of the geographical area for which this protection screen is intended, taking into account the arthropod species living there and for unless some of which it will be designed to form a mechanical barrier preventing the passage through it.

In a more general way, according to the needs and the destination of a given protection screen, one can seek a compromise in its definition, between the extent of its effectiveness against arthropod species, its transparency, its mechanical resistance for example shocks and exchanges of gas flows that it ensures through it.

This sheet may comprise one or more functional layers covering the core of glass or plastic on at least one of its faces. This protective screen is then constituted by a multilayer sheet, at least partially transparent, which is perforated.

Of course, this shield may also have one or more mounting holes, which are then separate ventilation holes and not intended to ensure the passage of a gaseous fluid through the screen.

Preferably, outside of its holes, the sheet is solid and substantially continuous in its mechanical and chemical properties, within manufacturing tolerances.

When the core of this sheet is made of polymer, it is advantageously an extruded sheet, a molded sheet or a sheet obtained by casting or made by three-dimensional printing (3D).

Advantageously, such a protective screen forms a purely mechanical barrier, which eliminates all the problems currently encountered with the massive use of mosquito nets pre-impregnated or covered with insecticide.

In various particular embodiments of this shield, each having its particular advantages and likely many possible technical combinations:

at least a majority of these ventilation holes have a constant section or comprise at least one section restriction in a direction extending between the two faces of said sheet.

Advantageously, each ventilation hole has a flared shape such as conical.

Alternatively, each air hole has a constriction. For example, this constriction may be placed at a portion of the vent hole opening on one side of this sheet or in the thickness of the sheet, for example by being positioned in a central portion, or substantially central, of the corresponding ventilation hole. In the latter case, the ventilation hole may have a longitudinal section, that is to say in a direction extending between the two faces of the sheet, having a shape reminiscent of the general shape of a diabolo.

Remember that such an aeration hole has a first portion of flared shape, followed by a constriction, followed by a third portion of flared shape. Very advantageously, such an embodiment makes it possible to reduce the visual impact of the presence in the corresponding ventilation hole of one or more layers in order to increase the light transmission coefficient of the sheet, irrespective of the angle of view. Indeed, the projected surface, or imprint, of this vent hole for a given opening diameter is minimized regardless of the angle of view.

In addition, such a configuration of ventilation holes can significantly lower the temperature of the air flowing through the shield, and thus to obtain a cooling of the air when the outside temperatures are hot. It was found that this refreshment was all the more marked as the air temperatures were high. this sheet is configured to ensure a cooling of the air passing through it, or passing through its ventilation holes.

This sheet then has a thickness and a configuration of longitudinal section of at least a majority of its ventilation holes, preferably all of its ventilation holes, ensuring a cooling of the air passing through the sheet.

For example, the longitudinal section of each vent is flared as conical or still has a constriction such as a constriction.

Such a cooling of the air passing through the screen is all the more marked as the air flow through the sheet is important, whether the air is hot or that the sectional narrowing of each ventilation hole is important. .

the lateral displacement of a ventilation hole during an elastic deformation of the sheet being Dc, 2 Dc is less than or equal to the largest dimension, and still the smallest dimension, of the main body of these arthropods against which this screen provides protection, this main body excluding the head and appendages of the corresponding arthropods.

This ensures advantageously that even in case of elastic deformation of the sheet, for example under the effect of wind, arthropods against which this shield provides protection remains effective in forming an impenetrable barrier to them.

This value of Dc is dependent on the constituent material (s) of the sheet, its thickness, its dimensions and the applied stress. The value 2 Dc is the maximum opening obtained during the opposite displacement of the upper and lower parts of a ventilation hole, without plastic deformation, when an external force is applied to the screen in a perpendicular direction or substantially perpendicular to it, while this screen is held in position for example by its peripheral edge.

- The surface of each ventilation hole is greater than 2000 pm ² and even better at 3500 pm ² to ensure sufficient gaseous fluid exchange through the shield.

This surface is the minimum surface that must present each vent hole to ensure a satisfactory ventilation. said screen has a light transmission coefficient which is greater than or equal to 70%, and even more preferably greater than 80%,

said air holes have a cross section that is oval, elliptical or oblong,

the section of each hole has a Ga value of between 0.1 and 8 mm in its largest dimension and a value Pa of between 500 μm and 1.2 mm in its other dimension, the Ga value being greater than the largest dimensions of the arthropods against which this screen provides protection, while its value Pa is less than or equal to the largest dimension of the main body of these arthropods against which this screen provides protection, the main body excluding the head and appendages of corresponding arthropods.

Such an embodiment is particularly advantageous, for illustrative purposes only, to form a screen for protection against mosquitoes and in particular the tiger mosquito.

Surprisingly, it has been observed in tests that, although the oval, oblong or elliptical aeration holes have one of their dimensions which is large, or even greater than the largest of the arthropods against which this Screen provides protection, to increase the exchange of gas flow through the screen, the latter was an impassable mechanical barrier arthropod against which it was designed.

said sheet has a thickness of between 50 μm and 10 mm, and even better between 50 μm and 6 mm.

Thus, and depending on its thickness, this sheet may be flexible, semi-rigid or rigid.

- The opening rate of said sheet, defined as the ratio of the surface of the ventilation holes to the total surface of said sheet is greater than 1%, preferably between 1% and 50%].

Even more preferably, this opening rate is between [2% and 25%].

said sheet comprises a core made of a material chosen from the group comprising polycarbonate, poly (methyl methacrylate) (PMMA), a polyethylene, a polypropylene, an ethylene / propylene copolymer, polyurethane, polystyrene, acrylonitrile butadiene styrene (ABS), polyethylene terephthalate (PET) or an association of several thicknesses of the same material of these plastics or of several plastics.

More generally, any polymer known for its optical transparency properties can be implemented.

- This shield is flat or essentially flat, or not flat.

In the latter case, it may for example be at least partially curved or curved.

the outer face of the core of said sheet comprises one or more anti-scratch layers, and / or at least one anti-reflection layer covering at least a part thereof and / or a masking layer such that coloring layer, preferably placed under at least one anti-scratch layer,

- The sheet can also be treated anti-UV.

By way of example, it then comprises in its mass a UV absorber or at least one anti-UV film, which covers at least one face of said core.

said ventilation holes are arranged on said sheet to represent a drawing, a pattern, a sign such as a number, a letter or a pictogram or a combination of these elements.

Alternatively, these ventilation holes can also be regularly spaced between them while being aligned.

- each vent hole having a side wall, or a belt side walls, in one piece; for at least some of said ventilation holes, the portion of at least one face of said sheet delimiting the edge of each of these ventilation holes and / or the side wall, or the side wall belt, delimiting each of the holes corresponding comprises at least one layer configured to increase the light transmission coefficient of said sheet relative to the light transmission coefficient of a single sheet whose ventilation holes are devoid of said layer or layers. The portion of the face of the sheet delimiting the edge of a ventilation hole is therefore the portion of this face immediately adjacent to the ventilation hole and not the whole of this face.

Preferably, said at least one layer configured to increase the light transmittance comprises a layer of colored charges, preferably dark colored charges, for example black, gray, brown or yellow pigments. Here, the term "colored charges" is understood to mean solid, colored particles which are intended to improve the light transmission properties of the support on which they are placed by adsorbing the light rays passing through them, which notably makes it possible to eliminate light interference. These particles may be added to a composition for deposition on a surface or formed by the interaction of a heat source with the material constituting the support.

Preferably, this side wall or side wall belt radially delimiting the corresponding ventilation hole comprises a plurality of layers configured to increase the light transmission coefficient of said sheet.

Advantageously, said layer or layers are placed on the surface of said wall or said lateral walls and / or in the thickness of said sheet.

For example, the total thickness of said layer or layers is between 0.1 and 250 μm.

The optical treatment of the inner surface of each vent hole by the formation of one or more dark colored layers such as black or gray, absorbs and / or block the light rays (reflected and diffracted) propagating in this or these layers thus formed.

It is surprisingly observed that the formation of this or these layers makes it possible to appreciably improve the light transmission of the sheet relative to a sheet whose aeration holes would have been untreated, because this minimizes the diffraction phenomena and reflection caused by the presence in the sheet of ventilation holes. This results in a significantly improved visual comfort for the user.

Said layer or layers thus formed form absorption layers of parasitic light rays which pass through them.

- Said sheet being made of a plastic material, its peripheral portion has an extra thickness formed by adding an overmolded plastic material.

The present invention also relates to a glazing element consisting of a shield against arthropods, as described above. Advantageously, this glazing element is transparent and has a light transmission coefficient that is greater than or equal to 70%, and more preferably greater than 80%.

Preferably, this glazing element can be treated anti-UV.

The present invention also relates to a construction element comprising a shield against arthropods, as described above.

As a purely illustrative example, this construction element may be a window comprising a fixed frame and a movable frame pivotable relative to the fixed frame, the mobile frame being equipped with at least one protective screen as previously described as glazing. Alternatively, this element of construction may comprise a first transparent glazing unit mounted on the movable frame and such a protection screen received in a housing of the fixed frame, this screen forming a second transparent or opaque glazing which is fixed. In the latter case, it is then possible to move the movable frame of a first so-called closing position, in which it is fully pressed against the fixed frame by sealing the construction element to a second position called opening in which the movable frame no longer ensures tightness with the fixed frame but allows the passage of air.

This building element can still be a slab or a frame intended to close an opening in a building. These can be colored.

Thus, this building element finds particular applications to close an opening in a building such as a building, house or building.

The present invention further relates to a hull for a child moving vehicle, such as a stroller or pram, or for a bed such as a cradle, comprising a shield against arthropods as described above.

Advantageously, this shell which is mounted on or connected to the frame of the vehicle or the bed, allows them to be closed to isolate the child or newborn arthropods for which this screen is intended, while ensuring sufficient ventilation.

The present invention also relates to the use of a shield against arthropods as described above, to isolate a space of mosquitoes, including the tiger mosquito, while by allowing adequate ventilation of this space, the latter being intended to be occupied by humans, animals or food. More generally, the present protection screen has applications in many technical fields, for example in filter screens for mosquito traps, window-screen combinations (when the window is open, the screen replaces the window automatically), the plates or ventilation screens of housing or industrial building, the plates of passage of cables, in particular to prevent that the pests pass while ensuring a good ventilation.

The present invention also relates to a method of manufacturing a shield against arthropods, as described above.

According to the invention, a sheet having a core of glass or plastic material is taken, said sheet being at least partly transparent, at least one removable protective layer covering at least one face of said sheet, and holes are made of aeration in the assembly comprising said sheet and said at least one removable protective layer, arranging the same to ensure passage of air through said sheet, each of said aeration holes being also configured to prevent passage arthropods through it.

According to one embodiment of the method of the present invention, said ventilation holes are arranged on said sheet to represent a drawing, a pattern, a sign such as a number, a letter or a pictogram or a combination of these elements. .

According to another embodiment of the method of the present invention, said aeration holes are made in this assembly by cutting with pure water jet, or by laser, or by milling.

With the existing methods, the vision through the perforated sheet is altered especially as there are holes, which is particularly the case of mosquito nets. Indeed, the holes themselves generate visual discomfort and the surrounding surfaces of the holes have optical properties often altered. This is further accentuated with a greater thickness of the leaf.

The alterations created around the holes (edge effect) are caused by the projections of additives (in a jet of water), by a blade with an inadequate profile (cutting of the core, punching), by a blade geometry unsuitable forest / milling cutter (drilling), excess heating of the material (laser), a bead of material (perforation), a weld line (injection).

Finally, there is currently no method capable of accurately producing small holes, for example of the order of a millimeter in the case of mosquito nets to barrier tiger mosquitoes, while ensuring a very high good ventilation, and retaining much of the optical properties of the leaf material in the areas near the holes.

Consequently, the ventilation holes are preferably made:

- By cutting pure water jet to avoid impacts around the holes caused by the additives added to the water to improve the cutting. Indeed, these impacts alter the optical qualities of the material. By way of example only, a Mecanumeric quickjet II ^® machine can be used to make the cuts.

- Laser cutting with pulses of short duration typically less than a few milliseconds to avoid excessive heating around the holes. For example, a Trotec Speedy 100 ^® C0 ₂ laser machine may be used.

- By milling, for example with a single thread mill for ejecting chips at a speed of the order of 10,000 rev / min. For example, a CharlyRobot 2U ^® machine can be used.

In all these examples, it will be possible to start the cutting path in the form to be cut to avoid irregularities on the finished product.

According to yet another embodiment of the method of the present invention, having produced said ventilation holes, and at least one face of said sheet still being covered with said at least one removable protective layer, it is formed, for at least some said ventilation holes, on the portion of at least one face of said sheet delimiting the edge of each of these ventilation holes and / or the side wall, or the side wall belt, delimiting each of the holes corresponding to the at least one layer configured to increase the light transmittance of said sheet relative to the light transmittance of the same sheet whose ventilation holes are devoid of said layer or layers.

Preferably, said at least one layer configured to increase the light transmission coefficient of this sheet will be formed from least one layer of colored charges, which will be obtained by:

by the implementation of a laser beam to carry out a surface treatment such as, for example, the process known as thermal foaming,

by depositing an appropriate aerosol paint composition,

- by a sol-gel process

or by depositing a solution comprising a solvent and colored fillers.

In the first case, the advantages of using a laser beam for "thermal foaming" are particularly related to obtaining a particularly precise work and foaming tints that can be varied.

By way of illustration only, it will be possible to implement a laser source of wavelength 1.06 μm, with a power of 10 W and having a scanning speed of 35 m / min on a polycarbonate sheet. A dark gray coloration is then obtained which can be located at the immediate approach of the holes and on the walls of the ventilation holes accessible to the laser beam.

For the other two treatment methods identified above, the solvent is chosen as a function of the constituent polymer of the sheet considered in order to be able to dissolve its surface and come to incrust the colored charges.

As a purely illustrative example, this solvent may be an organic solvent such as methanol, cyclohexanone, acetone, pyridine or methylene chloride. This solvent can be used pure or as a mixture, for example with water.

For example, the mixture can then be dispersed by spray with a conventional paint gun with a small diameter mouth, or a screen printing type coating, or a soaking sol-gel type. The masked surfaces, for example with the protective layer, will then be covered and at least the portion of the ventilation holes left visible by the drilling.

The main advantage of using these techniques is the speed of implementation over large areas.

As a purely illustrative example, a mixture associated with PMMA may be composed of 95% by volume of acetone with 5% of carbon black, such as for example Cabot ^® Emperor 1200, or any other carbon having very fine particles, compatible with solvents and good rheological behavior to ensure a good implementation. This mixture is for example projected using a Revell ^® airbrush having a nozzle of 0.1 mm.

In all cases, the solvent can be added, alone or with the colorant, photochromic elements based on silver chloride (such as Sigma Aldrich ^® AgCl having a purity greater than 99%) especially for a glass sheet, or spiro-oxazine (Tokyo Chemical Industries ^® ) especially for the case of polymers.

The advantage of photochromic agents is that they become darker with increasing light rays, that is to say at the moment when light scattering in the leaf, largely caused by the large number of holes , must be limited. Compared to a situation without treatment, it is observed that the small discomfort that could be caused by the presence of the colored charges, is non-existent when the light rays are of low intensity.

Colored fillers can also be incorporated into a polymer (via a masterbatch) to ensure good mixing with the solvent.

According to yet another embodiment of this method, said layer or layers are formed on the surface of said wall or said lateral walls and / or in the thickness of said sheet.

As a purely illustrative example, the total thickness of said layer or layers is between 0.1 and 250 μm.

The present invention further relates to a shield against arthropods comprising

said air holes being intended to ensure the passage of a gaseous fluid through this screen and

said screen has a light transmission coefficient which is greater than or equal to 70%, and even more preferably greater than 80%.

According to one embodiment of this screen, the area of each ventilation hole is greater than 2000 pm ² and even better at 3500 pm ² to ensure sufficient aeration, or exchange of gaseous fluid through this shield.

According to yet another embodiment of this screen, the opening rate of said sheet, defined as the ratio of the surface of the ventilation holes to the total surface of said sheet is greater than 1%, preferably between 1% and 50%].

Even more preferably, this opening rate is between [2% and 25%].

The present invention also relates to a shield against arthropods such as insects, cockroaches and spiders, comprising

said aeration holes being intended to ensure the passage of a gaseous fluid through this screen.

According to the invention, each ventilation hole having a lateral wall, or a sidewall belt, in one piece, for at least some of said ventilation holes, the portion of at least one face of said delimiting sheet the edge of each of these ventilation holes and / or the side wall, or the side wall belt, delimiting each of the corresponding holes comprises at least one layer configured to increase the light transmission coefficient of said sheet with respect to the coefficient of light transmission of the same sheet whose ventilation holes are devoid of said layer or layers.

According to one embodiment of this protection screen, said at least one layer comprises a layer of colored charges, preferably charges of dark color and even better of black or gray color.

According to another embodiment of this screen, the surface of each aeration hole is greater than 2000 pm ² and even better at 3500 pm ^{2 in} order to ensure sufficient aeration, or exchange of gaseous fluid through this screen. protection.

According to yet another embodiment of this screen, the opening rate of said sheet, defined as the ratio of the surface of the vent holes on the entire surface of said sheet is greater than 1%, preferably between [1% and 50%].

Even more preferably, this opening rate is between [2% and 25%].

According to yet another embodiment of this protection screen, the remainder of said sheet being entirely transparent or translucent.

According to yet another embodiment of this protection screen, said lateral wall or said lateral wall belt comprises a plurality of layers configured to increase the light transmission coefficient of said sheet.

According to yet another embodiment of this protection screen, said layer or layers are placed on the surface of said wall or said side walls and / or in the thickness of said sheet.

According to yet another embodiment of this protection screen, the total thickness of said layer or layers is between 0.1 and 250 μm.

According to yet another embodiment of this protection screen, at least a majority of the ventilation holes has a constant section or has a section restriction in a direction extending between the two faces of said sheet.

Preferably, each vent has a flared shape or has a constriction. This constriction can be placed for example in the thickness of the sheet or at a portion of the corresponding vent hole opening on a face of this sheet.

According to another embodiment of this protective screen, said sheet is configured to provide cooling of the air passing through its ventilation holes.

The present invention also relates to a shield against arthropods, such as insects, cockroaches and spiders, comprising

said aeration holes being intended to ensure the passage of a gaseous fluid through this screen. According to the invention, at least a majority of these ventilation holes comprise a section restriction in a direction extending between the two faces of said sheet.

According to one embodiment of this protection screen, each ventilation hole has a flared shape such as frustoconical. Alternatively, each air hole has a constriction.

As a purely illustrative example, this constriction may be placed at a portion of the corresponding ventilation hole opening on one side of this sheet or in the thickness of the sheet, for example by being positioned in a central portion, or substantially central, of the corresponding ventilation hole.

In the latter case, the ventilation hole may have a longitudinal section, that is to say in a direction extending between the two faces of the sheet, having a shape reminiscent of that of a diabolo.

According to yet another embodiment of this protection screen, the lateral displacement of a ventilation hole during an elastic deformation of the sheet being Ax, 2 Ax is less than or equal to the largest dimension, even better the smaller dimension, the main body of these arthropods against which this screen provides protection, this main body excluding the head and appendages of arthropods corresponding.

According to yet another embodiment of this protection screen, each ventilation hole having a lateral wall, or a belt of side walls, in one piece, for at least some of said ventilation holes, the portion of at least one face of said sheet delimiting the edge of each of these ventilation holes and / or the side wall, or the side wall belt radially delimiting each of the corresponding holes comprises at least one layer configured to increase the transmission coefficient light of said sheet with respect to the light transmission coefficient of the same sheet, or identical sheet, whose ventilation holes are devoid of said layer or layers.

According to yet another embodiment of this protection screen, said side wall or said side wall belt has a plurality of layers configured to increase the light transmittance of said sheet.

According to yet another embodiment of this protection screen, said at least one layer is a layer of colored charges, preferably charges of dark color and even better of black or gray color.

According to yet another embodiment of this protection screen, the total thickness of said layer or layers is between 0.1 and

250 pm.BREW DESCRIPTION OF THE DRAWINGS

Other advantages, aims and particular features of the present invention will emerge from the description which follows, made for an explanatory and non-limiting purpose, with reference to the appended drawings, in which:

- Figure 1 is a partial view in perspective of a shield against arthropods according to a first embodiment of the present invention, an edge of this screen being pressed against a wall defining an opening in a construction;

- Figure 2 is a partial top view and enlarged of a shield against arthropods according to a second embodiment of the present invention;

FIG. 3 is a schematic representation of ventilation holes of a protective screen according to a third embodiment, these ventilation holes having an elliptical section;

- Figure 4 is an enlarged and partial view of a protective screen showing an oblong ventilation hole with its transverse and longitudinal axes;

- Figure 5 is an enlarged and partial view of a shield showing an air hole in front of which is placed a tiger mosquito;

DETAILED DESCRIPTION OF EMBODIMENT

THE INVENTION

First, we note that the figures are not scaled. Figure 1 schematically shows a shield against arthropods, including insects and spiders, according to a first embodiment of the present invention.

This screen 10 which forms here a glazing element, comprises a plate 11 of plastic material, here poly (methyl methacrylate) - PMMA, obtained by casting. It has a thickness of two (2) mm.

This plate 11 is perforated with ventilation holes 12 of oblong shape, these ventilation holes 12 being aligned in two directions (x, y) in the plane of the plate being regularly spaced from each other. Of course, the ventilation holes 12 could alternatively be arranged in staggered rows.

The opening rate of this plate 11 is twenty-five (25)%, these aeration holes 12 having been made by cutting by pure water jet.

The section of each of these oblong holes which are identical, has a Ga value of the order of 3 mm in its largest dimension, that is to say in a direction substantially transverse to the plate, and a Pa value of the order of 800 pm in its other dimension, that is to say substantially the height thereof.

Each aeration hole 12 of this plate 11 was treated by means of a composition comprising 95% by volume of acetone and 5% of fillers colored here with black carbon pigments, in order to form a layer of colored fillers ensuring increase of the light transmission of the screen 10.

This plate 11 advantageously has a light transmission coefficient of greater than 80%.

Figure 2 schematically shows a shield against arthropods according to a second embodiment of the present invention.

This protective screen 20 is here formed of a sheet 21 of polycarbonate having a thickness of 250 pm so that the latter is flexible and can be rolled up / unwound in the manner of a blind to release or close an opening.

This sheet 21 is perforated with ventilation holes 22 of oblong shape, the opening rate of this sheet being 2.5%.

These ventilation holes 22 have advantageously been formed by laser cutting of the sheet 21, and more precisely by means of a laser cutting machine C0 ₂ of 100W power, with a speed cutting speed of 0.6 m / min. The spot size of the laser beam at the surface of the sheet is about 70 μm.

Each aeration hole 22 of this sheet was then treated with a composition comprising a solvent, in this case pyridine and fillers stained black carbon pigments to form a layer 23 improving the light transmission of this sheet.

This sheet 21 has also received an anti-UV treatment on the surface.

Figure 3 is a schematic representation of vent holes 30 of a shield according to a third embodiment, these vent holes 30 having an elliptical shaped section.

This protective screen comprises a sheet 31 having a thickness of the order of 300 μm.

The edges of this sheet 31 are not perforated thus allowing better mechanical grip of the frame uprights on the sheet, and thus increasing the mechanical strength, for example impact.

The sheet 31 which is transparent, is made of polycarbonate such as polycarbonate Makrolon ^® .

The substantially elliptical aeration holes of dimensions 1 mm by 4 mm were obtained by cutting with a jet of pure water.

The holes are staggered and nested to obtain a vacuum density of the order of 0.25 in the useful area of the protective screen.

The interior of each vent hole was spray painted with a spray of aerosol paint comprising a carbon / solvent pigment composition, so as to obtain a very thin uniform coating thickness in the order of a few microns.

In order to demonstrate the technical advantage provided by the protective screens of the invention, measurements of the illuminance through a mosquito net of the state of the art, the protective screens described in Figures 1 and 2 before the ventilation holes are made, and after the completion of these ventilation holes but before their treatment to improve the light transmission coefficient of the corresponding screen, and then after such treatment of each ventilation hole, are presented in Table I.

These measurements were carried out at ambient temperature of about 20 ^° C., by means of a tungsten light source having a reflector having a power of 45W, a light detector such as a an ISO-TECH ILM-1 ^® luxmeter and a lens for focusing the luminous flux passing through the object interposed between the source and the light detector on the sensor of the latter.

Table: Results of optical measurements

These measures clearly show that:

the luminous illumination through screens of protection of the invention is much greater than that measured through mosquito nets of the state of the art, and

- By treating the ventilation holes and / or the peripheral zone of each ventilation hole to form at least one layer increasing the light transmission coefficient, higher illuminance is obtained than the same products without treatment.

Traction tests were also performed on undrilled protection screen samples and air holes using an MTS autotrac ^® machine. The test conditions were as follows: - test piece alters 160 mm total length, 80 mm useful length, 10 mm useful width, and

- Traction speed of the order of 50 mm / min.

The following measures were obtained:

- tests of specimens without holes: 1162N of breaking strength for a sheet of polycarbonate (PC) 2 mm thick without holes, and

- test specimens with holes: 1025N breaking force for a polycarbonate (PC) sheet of 2 mm thickness with oval holes and 1027N breaking force for this same sheet but with oblong holes.

These measurements show that the ventilation holes made in the sheets have a slight effect on the tensile performance of the sheets.

Similarly test Charpy impact strength according to isol79 standard, produced with a machine Wolpert Werke Gmbh ^No. PW5K-E mobile 7.5 Joules, test piece 80 mm in length and 10mm in width, have shown that n ' There was no significant influence on the mechanical strength of the leaves resulting from the presence of ventilation holes.

Additional tests have been carried out to demonstrate the advantageous effects provided by a protective screen of the invention in the cooling of a flow of air passing through it.

Wind tunnel tests were thus carried out by positioning various protective screens in turn in the middle of a sealed tunnel 110 cm long and substantially square section having 7.5 cm side. This tunnel was placed in a closed and thermoregulated enclosure of sixty (60) m ³ .

A variable speed blower with the possibility of heating the supply air, reference KH2113 (manufactured by Kompernass GmbH, 44867 Bochum, Germany) was placed at the entrance of this tunnel.

The air temperature was measured at different locations in the tunnel with thermal sensors, including precision digital thermometers.

This tunnel was long enough to have a steady flow, with measurements taken when the temperature was stable.

These tests were carried out with the following protection screens: * Commercial type mesh screen

polyvinyl chloride (PVC) coated weave with a thickness of 0.26 mm, hole density (t) of 38,000 t / m ² .

* Ml screen

PMMA sheet with a thickness of 2 mm,

hole density (t) of 5,000 t / m ² ,

shape of longitudinal section, i.e. in a direction extending between the two faces of the sheet, straight ventilation holes (without clearance) with inlet and outlet diameter of 1.0 mm .

* M2 screen

Polycarbonate sheet (PC) having a thickness of 2 mm,

hole density (t) 5,000 t / m ² ,

shape of the longitudinal section of the diabolo vent holes (hereinafter referred to as D-shape) with inlet and outlet diameter of 1.0 mm, with a throttle approximately centered in the thickness of the sheet of minimum dimension 0 , 6 mm.

* M3 screen

Polycarbonate sheet (PC) having a thickness of 2 mm,

hole density (t) 5,000 t / m ² ,

shape of the longitudinal section of each cone air hole (hereinafter called C shape) with inlet diameter of 1.5mm, output dimensions of 0.5mm.

The air flow is noted arbitrarily Di with i = 1 to 3, this air flow being stronger and stronger when the index i increases.

In conclusion, these thermal tests have demonstrated that:

Commercial mesh nets have no thermal effect whatever the ventilation and / or temperature conditions.

The shields of the invention, whatever the version Ml, M2 or M3, induce a cooling of the air passing through them.

The higher the air flow rate, the better the cooling of the air. The higher the temperature measured downstream of the tunnel, that is to say after the shield, is high, the greater the temperature variation is important.

The presence of a large constriction, that is to say a strangely small section, in each ventilation hole increases the difference in temperature measured between the upstream and downstream of the screen protection.

These tests have also demonstrated that a longitudinal section, that is to say between the two faces of a sheet, having a diabolo shape ensures not only an optimization of the cooling of the air passing through the screen but also provides greater visual comfort for the user, the footprint of the hole, or its projected surface on one side, being smaller than a frustoconical shaped hole for example.

Complementary tests were also conducted to study the variation of the light transmission through various objects.

The operating conditions were as follows: a light source sending a uniform beam on a lens, which converged the luminous flux on a fluxmeter in order to be able to measure the quantity of light transmitted. The object to be studied was introduced at the exit of the light source.

Note:

* method 1 = laser foaming, method 2 = chemical process.

When not specified, process 2 was implemented.

Form C = longitudinal section, that is to say in a direction extending between the two faces of the sheet, the conical shaped air hole

Shape D = longitudinal section of the diabolo-shaped vent hole.

The following points result from these measures:

a) the illuminance through the mosquito net trade is much lower than all screens, objects of the invention regardless of the shape of the ventilation holes tested, the treatment method used, the density of holes or the color of the layers formed in these ventilation holes to improve the light transmission coefficient of the corresponding sheet,

b) higher illuminance is obtained with the formation in each ventilation hole of one or more layers to improve the light transmission coefficient of the corresponding sheet rather than without treatment of the ventilation holes of this sheet, c) - a range of treatment colors appears optimal (dark colors and, in particular, blue gray) to ensure optimum light transmission (% high),

d) - a hole profile (in the thickness) with the shape "diabolo centered" optimizing the aesthetic appearance by reducing the impact of the treatment on the vision regardless of the angle of view, and maximizing the light transmission . Indeed, the projected area of the hole for a given passage diameter is minimized, regardless of the angle of view.

Figure 4 is an enlarged and partial view of a shield 40 showing a single vent 41 of oblong shape. This shield 40 comprises an integral sheet comprising a first face 42 and a second face (not shown). This sheet has a plurality of ventilation holes 41 extending and opening on both faces 42 of this sheet to allow the passage of air therethrough. Only the free end of a vent hole 41 opening on the first face 42 of this sheet and therefore contained in this face, is shown for the sake of simplicity.

The portion, or free end, of the vent hole opening on the first face 42 and has a first dimension along a transverse axis 43 to this hole and a second dimension along a longitudinal axis 44 to this hole.

Advantageously, the dimension of this ventilation hole 41 along its longitudinal axis 44 is greater than the largest dimension of the arthropods against which this screen provides protection while its dimension along the transverse axis 43 is less than or equal to to the largest dimension of the main body of these arthropods against which this screen provides protection, this main body excluding the head and appendages of the corresponding arthropods.

This ensures a greater air flow through the shield 40 while ensuring its role as a mechanical barrier against the arthropods corresponding.

Figure 5 is an example of implementation of the screen of Figure 4 to form a mechanical barrier against tiger mosquitoes.

Claims

1. Screen for protection against arthropods comprising

- a sheet (11, 21, 31) having a core of glass or plastic, said sheet (11, 21, 31) being at least partly transparent and having a plurality of ventilation holes (12, 22, 30 )

each of said vent holes (12, 22, 30) being configured to prevent the passage of arthropods therethrough,

said ventilation holes (12, 22, 30) being intended to ensure the passage of a gaseous fluid through this screen (10), said sheet having two faces,

characterized in that

at least one of the portions opening on said faces of at least some of said ventilation holes has an elongate cross section, said section comprising a longitudinal axis and a transverse axis, the dimension of each of said portions along the longitudinal axis being greater than the largest dimension of arthropods against which this screen (10) provides protection, the dimension of each portion along the transverse axis being less than or equal to the largest dimension of the main body of these arthropods against which this screen (10) provides protection, the main body excluding the head and appendages of the corresponding arthropods.

2. Screen according to claim 1, characterized in that at least a majority of said ventilation holes has a constant section or has a section restriction in a direction extending between the two faces of said sheet.

3. Screen according to claim 2, characterized in that each vent has a flared shape or comprises a constriction.

4. Screen according to any one of claims 1 to 3, characterized in that said sheet is configured to provide cooling of the air passing through its ventilation holes.

5. Screen according to any one of the preceding claims, characterized in that the lateral displacement of a ventilation hole during an elastic deformation of the sheet being Dc, 2 Dc is less than or equal to the largest dimension of the main body of these arthropods against which this screen (10) provides protection, the main body excluding the head and appendages of the corresponding arthropods.

6. Screen according to any one of the preceding claims, characterized in that said screen (10) has a light transmission coefficient which is greater than or equal to 70%.

7. Screen according to any one of the preceding claims, characterized in that said ventilation holes (12, 22, 30) have a right cross section of circular, oval, elliptical or oblong.

8. Screen according to any one of the preceding claims, characterized in that the section of each hole has a Ga value between 0.1 and 8 mm in its largest dimension and a Pa value between 500 pm and 1.2. mm in its other dimension, the value Ga being greater than the largest dimension of the arthropods against which this screen (10) provides protection, while its value Pa is less than or equal to the largest dimension of the main body of these arthropods against which this screen (10) provides protection, the main body excluding the head and appendages of the corresponding arthropods.

9. Screen according to any one of the preceding claims, characterized in that the opening rate of said sheet (11, 21, 31), defined as the ratio of the surface of the ventilation holes (12, 22, 30). ) on the total surface of said sheet (11, 21, 31) is between [1% and 50%].

10. Screen according to any one of the preceding claims, characterized in that each vent hole having a side wall, or a belt side walls, in one piece, for at least some of said ventilation holes (12). , 22, 30), the portion of at least one face of said sheet (11, 21, 31) delimiting the edge of each of these ventilation holes and / or the side wall, or the side wall belt, delimiting each of the corresponding holes comprises at least one layer configured to increase the light transmission coefficient of said sheet relative to the light transmission coefficient of the same sheet whose ventilation holes are devoid of said layer or layers.

11. Screen according to claim 10, characterized in that said side wall or said side wall belt comprises a plurality of layers configured to increase the light transmittance of said sheet.

12. Screen according to claim 10 or 11, characterized in that said layer or layers are placed on the surface of said wall or said side walls and / or in the thickness of said sheet.

13. Screen according to any one of claims 10 to 12, characterized in that said at least one layer is a layer of colored charges, preferably charges of dark color and even better of black or gray color.

14. Screen according to any one of claims 10 to 13, characterized in that the total thickness of said layer or said layers is between 0.1 and 250 pm.

15. A glazing element consisting of a shield against arthropods according to any one of claims 1 to 14.

16. Construction element comprising a shield against arthropods according to any one of claims 1 to 14.

17. Hull for a child or bed moving vehicle comprising a shield against arthropods according to any one of claims 1 to 14.

18. Use of the shield against arthropods according to any one of claims 1 to 14, for isolating a space, mosquitoes, including tiger mosquito, while allowing ventilation of this space, said space being intended to be occupied by humans, animals or food.

19. A method of manufacturing a shield against arthropods according to any one of claims 1 to 14, characterized in that takes a sheet (11, 21, 31) having a core of glass or plastic , said sheet (11, 21, 31) being at least partially transparent, at least one removable protective layer covering at least one face of said sheet (11, 21, 31), and in that aeration (12, 22, 30) in the assembly comprising said sheet (11, 21, 31) and said at least one removable protective layer, arranging the same to ensure passage of air through said sheet (11, 21, 31), each of said vent holes (12, 22, 30) being also configured to prevent the passage of arthropods therethrough.

20. The method of claim 19, characterized in that said ventilation holes (12, 22, 30) is made by pure water jet cutting or by laser or by milling.

21. The method of claim 19 or 20, characterized in that having provided said ventilation holes (12, 22, 30), and at least one face of said sheet (11, 21, 31) is still covered with said at least one removable protective layer is formed, for at least some of said ventilation holes (12, 22, 30), on the portion of at least one face of said sheet (11, 21, 31) delimiting the edge of each of these ventilation holes and / or the side wall, or the side wall belt, delimiting each of the corresponding holes, at least one layer configured to increase the light transmittance of said sheet with respect to the light transmittance of the same sheet whose ventilation holes are devoid of said layer or layers.

22. Method according to claim 21, characterized in that at least one layer of colored charges is formed by the implementation of a laser beam, by deposition of an aerosol paint composition, by a sol-gel process or by again by depositing a solution comprising a solvent and colored fillers.

23. The method of claim 21 or 22, characterized in that said layer or layers are formed on the surface of said wall or said side walls and / or in the thickness of said sheet.