BE1022341A9 - METHOD AND APPARATUS FOR PRODUCING WATER-RESISTANT CARPET WITH A HIGH WATER ABSORPTION - Google Patents

Abstract

Described is a carpet, a method of making a carpet, and a device therefor, wherein the carpet has a carpet pile and a coated felt backing, e.g., non-woven such as a needle felt backing. The carpet is primarily a fibrous textile product that can absorb and retain water in gaps between fibers that are small enough to retain the water due to surface tension effects but open enough to allow evaporation or removal with a vacuum cleaner. A semi-finished product including carpet pile

made by tufting, weaving, fastening, felting, needling, punching or any other method known in the art for manufacturing textiles is laminated to a felt layer to form the felt back. The felt layer is a coated felt layer. The felt layer can be a needle felt.

Description

Method and device for producing a water-resistant carpet with a high water absorption

The present invention relates to a carpet, a method for producing carpet and a device for producing carpet, which carpet can be used, for example, in situations where a considerable amount of water occurs, such as in hotels in ski resorts, on ships, on jetties or in vehicles such as cars where passengers and drivers can bring snow.

Technical background

Carpet is commonly used as floor covering for large surfaces in offices, hotels and industrial buildings. Carpet designed for use in the winter, when large amounts of snow are brought in through shoes or boots, can be replaced by other carpets in the summer. After contact with large amounts of water, conventional carpet must be professionally removed and dried. In order to be able to install and remove the carpet in a space of a commercial building such as a hotel without disturbing the normal activities in the building, the carpet cannot be glued to the floor. If the carpet is not glued, the back of the carpet is preferably provided with a non-slip layer.

Various types of carpet are known which are made by producing a semi-finished layer with a carpet pile, for example a woven pile which is subsequently fixed in a carrier material or is formed as a needle felt. The semi-finished pile material is attached to a backing material and then coated with a further coating on the backing.

This coating on the back can for instance consist of a gel or a polyurethane foam, latex foam or PVC or even bitumen. Such materials can be applied in the liquid state with a casting or coating technique.

Where foams are used, they can absorb significant amounts of water, but it can be more difficult to get this water out of the foam, e.g. by evaporation. If parts of the carpet remain saturated with water at temperatures inside buildings such as hotels, they can rot, for example due to mold or bacterial growth.

Prior art carpets are difficult to recycle since it is difficult to separate the various materials. In order to be able to work with them easily and to lay them easily, carpets must also be flexible enough to be rolled up and laid in such a way that the laid carpet conforms to the floor on which it is laid. For carpet tiles it is important that the tiles are stiff. Stiffness prevents carpet tiles from curling and the floor covering becoming uneven. This means that it is difficult to make a carpet that can act as both a tile and a carpet.

For example, in WO 2005/08067 it has been proposed to form carpet squares as a multilayer structure with a semi-finished product and a thermally fixed felt backing between which an adhesive is applied.

However, this is an expensive production process. Moreover, the shaped carpet squares are preferably stiff and therefore they are less suitable for large carpets used in industrial and commercial buildings such as hotels. Also, the water resistance is not guaranteed since carpet tiles are not designed to be water resistant.

Summary of the invention

The present invention relates to a carpet, a method of producing carpet and a device for producing carpet which can be used, for example, in situations where a considerable amount of water occurs, such as in hotels in ski resorts, on ships, on jetties or in vehicles such as cars where passengers and drivers can bring snow into the vehicle. It is desirable to make such a carpet using traditional production methods and the associated production machines. It is also preferable to make rugs that are more environmentally friendly and easier to recycle while retaining their flexibility so that the rug can be laid and picked up easily. To prevent the carpet from sticking to the floor or subfloor (the traditional method), it is preferable if the carpet has a non-slip bottom. This anti-slip bottom must also be durable and be resistant to the abrasive effect caused by the movement of the carpet relative to the floor on which it is laid. To be useful in winter areas with a lot of snow such as ski resorts, it is preferable if the carpet can absorb significant amounts of water, which can then evaporate. In such areas, it would be preferable for the carpet to be water resistant so that the underlying floor is not damaged by water running through the carpet. It is preferable if the carpet has a durable top that is not damaged by sturdy boots such as ski boots. The top can be structured, i.e. with fiber bundles that form tops with valleys between them so that snow is removed when skiers walk on the carpet. Alternatively, it is also possible to use a flat product, such as a flat needle felt product.

In one aspect, the present invention provides a carpet, a method of making a carpet, and a device with which a carpet can be made as described below.

The present invention provides a carpet and a method for making a carpet with a carpet pile and on the back a coated non-woven layer such as a felt layer, e.g. a needle felt back. Embodiments of the present invention provide a carpet that is essentially a textile fiber product that can absorb and retain water in spaces between the fibers that are small enough so that the water is retained by surface tension effects, but open enough to allow evaporation or removal with a vacuum cleaner to make. Thus, in one aspect, embodiments of the present invention include making a semi-finished product including carpet pile made by tufting, weaving, fastening, felting, threading, punching or any other method known in the art for fabricating textile, and laminating. of the semi-finished product on a non-woven layer such as a felt layer to form the felt backing. Laminating is the technique for manufacturing material in multiple layers. A laminate is usually permanently assembled by means of heat, pressure, welding or adhesives.

The non-woven layer such as the felt layer is a coated felt layer. The felt layer can be a needle felt. The semi-finished product can for instance be made by structuring machines in which use is made of so-called fork needles. For example, fork needles can guide fiber bars into lamella beams that extend from the entrance to the exit of the needle machine. These bars guide the fiber beard from the input to the output side of the machine. Depending on the orientation of the fork needle, a rib or velor surface is introduced. Alternatively, the surface can also be unstructured.

Needle felt is sometimes described as being produced by needle punching of nonwovens by mechanically orienting and interlocking the fibers of a spunbond or carded web. This mechanical interlocking is achieved with many (e.g. thousands) felt needles with barbs that repeatedly go in and out of the fleece. Needle punching of a non-woven to make a needle felt can take place on a felting machine, a structuring machine (see above), or a random velor loom. For example, felting machines can have a number of needle plates, such as one to four needle plates, and the needle punching can take place from the top, the bottom, or the top and bottom. The primary function of this type of loom is interlocking fibers. The random velor needle loom has a brush bed placement system. Special crown type needles or fork needles can be used in this loom design. The needles push fibers into a moving brush bed plate. In this brush the fibers are transported from the entrance to the exit of the loom with zero drafting.

The non-woven layer such as the felt layer on the back can have a mixture of horizontally and vertically extending fibers. The ratio between horizontal and vertical depends on how the felt is made and how strongly the felt is worked with needles - more needle processing usually results in more fibers running at an angle or vertically. Parallel fibers in the carpet according to embodiments of the present invention create long open gaps for collecting and retaining water.

The semi-finished product including carpet pile can also comprise additional textile layers such as covering membranes, carriers and other felt layers.

In addition, an extruded coating is applied on the back and this coating is a thermoplastic polymer coating. The extrusion takes place with the aid of a screw-type extruder and a mold over the width of the carpet fleece, for example 2, 3 or 4 meters wide. Preferably, no combination of extruder and calendering is used to generate the thermoplastic layer, i.e., the thermoplastic layer is applied directly from a full-width extrusion die without intermediate intermediate calender rolls as is often done in PVC processing. Non-preferred methods for forming the thermoplastic substrate (which comes into contact with the floor or substrate on which the carpet is laid) and which are not considered to be part of the present invention are: a) Submerging in a polymer melt b) Casting with a liquid polymer / organic solvent mixture followed by removal of the solvent; c) Application of a dispersion of polymer and an organic solvent or water followed by removal of the solvent / water wherein the polymer forms a plastisol, an organosol or a latex.

The extruded backing layer is waterproof and preferably has anti-slip properties, which means that the carpet does not have to be glued to the floor. The impermeable extruded layer is preferably wear-resistant, but thin. The thickness can be between 0.025 mm and 0.6 mm, for example 0.2 to 0.25 mm. By coating at extruder melt temperatures, the extruded coating adheres to the bottom of the felt layer without significant penetration and filling of gaps between the fibers of the felt, which would reduce water retention. This is particularly the case when the same polymer or the same polymer family is used for both the extruded layer and the fibers of the felt. Due to the thin, but strong, and wear-resistant extruded thermoplastic underlayer, more felt can be used in the overall construction, meaning that instead of a thick latex layer at the bottom, there is a combination of a thin, wear-resistant impermeable, extruded thermoplastic underlayer and a felt layer. is used. This ensures improved water retention while maintaining or improving flexibility, strength and / or durability.

The invention further relates to a device for producing carpet with a carpet pile and a coated felt backing including a unit for extrusion coating of the backing for coating a semi-finished product including a carpet pile with felt backing for forming a carpet fleece. The semi-finished product including carpet pile can also comprise additional textile layers such as covering membranes, carriers and felt layers. The device may comprise the following: - an applicator unit for coating the felt backing and / or a semi-finished textile with an adhesive; - a fixing unit for fixing the felt backing and / or a textile semi-finished product with the glue; - an extrusion unit for the polymeric bottom layer for extrusion of a coating of the carpet fleece with a thermoplastic polymer layer.

The unit for making the textile semi-finished product may comprise equipment for making the carpet pile by tufting, weaving, fastening, felting or any other method known in the art. The device may comprise a unit for coating the textile semi-finished product with a latex.

The device according to embodiments of the present invention is striking because of the extrusion coating unit of the backside for applying a surface coating to the backside of the needle felt layer. This can be realized in a width of up to 4 meters.

According to embodiments of the present invention, one or more advantages described in more detail below can be achieved with a method that is striking because it comprises an extruded surface coating which is applied by extrusion to the felt back of the carpet fleece, which coating is a thermoplastic polymer. As indicated above, the extrusion takes place directly from the extrusion die on the felt layer.

The extruded coating and fibers is a thermoplastic polymer such as a polyolefin such as polypropylene.

Advantages of an olefin such as polypropylene include any or all of the following: easy to clean colourfast strong fiber soil and water resistant good stain resistance no static charging problems resistant to moths and mildew forms a good low pile carpet.

If desired, a curable extrudable polymer can be extruded and, if desired, a curing unit can be provided for curing the polymer, for example an infrared or circulating oven or a combination of both.

According to embodiments of the present invention, it is possible to use a non-woven layer such as a needle felt layer that can be attached to the semi-finished product in any known manner, e.g. by laminating, gluing, calendering, pressing.

After applying the extruded surface coating and optionally curing, the carpet including the non-woven layer such as the needle felt layer is bendable, has a waterproof bottom layer and preferably has a non-slip bottom. It is possible to roll up the carpet. This makes handling easier when laying the carpet. For recycling reasons, it is preferable not to use coating materials such as bitumen or PVC.

Typical extrusion coating materials can be a thermoplastic polymer material such as a polyolefin, for example polypropylene material or polypropylene with a high impact strength. The coating weight of the polymer can be between 30 and 600 g / m2, such as 200-250 g / m2.

The semi-finished product with carpet pile is preferably laminated or combined with the non-woven layer such as the needle felt using an adhesive such as EVA (ethylene vinyl acetate) or LDPE (low density polyethylene) that can optionally be applied in powder form and then heated in a circulating oven and / or an IR (infrared) oven and the layers are optionally compressed to melt the polymer and fuse the two layers together. The non-woven layer such as the needle felt can be a layer of 80 to 500 g / m2, such as 200-250 g / m2. Laminating is the technique of manufacturing a material in several layers. A laminate is usually permanently assembled by any suitable means such as heat, pressure, welding or adhesives.

An aspect of the present invention is the production of a carpet with an extruded bottom layer that is optionally anti-slip, waterproof, vulcanized or cross-linked, and which is applied to a non-woven layer such as a felt layer attached to a carpet pile semi-finished product. The pole product can be fixed with a latex material to improve the durability. Synthetic latex is preferred. The curing of the latex for the carpet pile can take place by means of chemical crosslinking or by means of heat, e.g. at a temperature between 60 and 160 ° C, and preferably about 130 ° C. The fibers used in the carpet preferably do not absorb water or should be coated with a sealing coating. Preferably, the carpet changes the density of the fibers from top to bottom - more open at the top and more close at the bottom to retain water due to surface tension effects. The water is absorbed into the open structure and then brought down into the carpet body by surface tension or "capillary wick" effects. The gradation in pore size from top to bottom, i.e. the pore size decreasing towards the bottom, helps to pull the water down in the carpet body. The total product can absorb water and allow the water to evaporate as it is generally, with the exception of the extruded backing, an open structure. The carpet according to embodiments of the present invention has a low weight, but has a high capacity to absorb water equivalent to being able to absorb at least twice its own weight. This water can easily evaporate due to the open nature of the non-woven layers such as the felt layers and the carpet pile and the non-water-absorbing nature of the fibers that prevents the fibers from becoming soaked. For this purpose, it is preferable to choose a material for the fibers that does not absorb water such as a polyolefin, for example a polypropylene. The fibers can be coated with a film that blocks water.

The final thickness of the carpet will generally be between 7 and 20 mm, more particularly between 9 and 15 mm in thickness.

An important aspect of embodiments of the present invention is the combination of much higher water absorption capacities than existing structures while the evaporation time of the water in the air (drying time) remains the same.

The manufacture of the textile semi-finished product and the coating steps can be carried out in an off-line or in-line process. The innovative carpet construction of the present invention can be made in a variety of different ways, each of which is an embodiment of the present invention.

The polymeric bottom layer is extruded and attached to the bottom of the non-woven layer such as the needle felt layer without any deep penetration into the non-woven layer such as the needle felt, but enough to be firmly attached to it so that the carpet remains an integral whole when it is laid and then recorded. The layer of extruded polymer is preferably attached to the non-woven layer such as the felt layer without significant penetration into the non-woven layer such as the needle felt. The non-woven layer such as the felt can, for example, have a thickness of between 1 and 10 mm. The low penetration ensures that the maximum amount of free space in the non-woven layer such as the needle felt remains available for water retention. The extrusion can be carried out horizontally or vertically. The extruded polymer can be foamed to reduce the amount used as long as the backing of the carpet is waterproof and durable.

The extruded layer is preferably less than 20%, more preferably less than 10% of the dry weight of the final carpet. The fiber part of the carpet, ie the part that has fibers with water retention gaps between them, is preferably at least 65%, more preferably at least 70% or 75% of the dry weight of the final carpet (maximum optionally about 85% or 90%). The extruded layer is preferably less than 150%, more preferably less than 120% of the dry weight of the felt backing layer to which this layer is applied.

Curing can take place in an oven such as a circulation oven that can be placed after the extrusion unit or perhaps even at a different location. To provide curing, it is preferable to use thermally curing polymers that cure by heating. Alternatively, polymers can be used that cure by means of IR or UV irradiation or chemically.

It is possible to make the carpet with a carpet pile and the non-woven layer such as the needle felt layer as a whole from material comprising the same polymer, e.g. a polyolefin such as polypropylene. This provides an environmentally friendly carpet that is easier to recycle.

The semi-finished product and the final carpet can be produced in widths of up to 5 meters.

Brief description of the drawings

The invention will now be explained with reference to the accompanying drawings, in which:

FIG. 1 shows a schematic section of a semi-finished product that can be used with embodiments of the present invention;

FIG. 2 shows a schematic section of an embodiment of the present invention.

Description of the exemplary embodiments

The present invention will be described with reference to certain embodiments and with reference to certain drawings, but the invention is not limited thereto, but only by the claims. The described drawings are only schematic and are non-limiting. In the drawings, some elements for illustrative purposes may be overly large and not drawn to scale. Where the term "comprising" is used in the present description and claims, other elements or steps are not excluded. Where an indefinite or definite article is used to refer to a singular noun, eg "an", "an" or "an", this reference also applies to the plural of that noun, unless specifically stated otherwise. The term "comprising" used in the claims is not to be interpreted as being limited to the means mentioned thereafter; other elements or steps are not excluded.

Furthermore, the terms first, second, third and the like in the description and in the claims are used to distinguish between comparable elements and not necessarily to describe a sequential or chronological order. The terms used in this manner are interchangeable under the right conditions and the embodiments of the invention described herein may also operate in a different order than described or illustrated herein.

Furthermore, the terms top, bottom, horizontal, vertical and the like in the description and claims are generally used to describe a carpet that has been laid horizontally unless it has been assigned a different meaning.

In the drawings, the same features are indicated by corresponding reference numerals, while a reference numeral occurring in several figures refers to the same element.

FIG. 1 shows a schematic section of a textile semi-finished product 4 that can be used with embodiments of the present invention to make a carpet 1. The textile semi-finished product 4 provides a wear-resistant surface as well as a textile layer that can absorb water while allowing free evaporation through its open pore structure. In one aspect, embodiments of the present invention include making the semi-finished product 4 including carpet pile made by tufting, weaving, fastening, felting, milling, punching or any other method known in the art for manufacturing textiles. The semi-finished product 4 can preferably have a non-woven layer such as a needle felt layer 3 and / or other textile layers such as covering membranes, carriers, felt layers. In another embodiment, the semi-finished product 4 is preferably made of a single material such as a layer made of 100% by tufting, weaving, fastening, felting, milling, punching or any other method known in the art for manufacturing textiles. For example, the semi-finished product 4 can only be made of a needle felt (i.e., layers 2 and 3 can be one integral product). The semi-finished product 4 preferably has fiber loops 2 that are exposed at the top and these loops can be reinforced by coating them with a material that fixes the loops and holds them in place. For example, the fibers of the loop can be coated after manufacture with a latex material, e.g. a transparent latex material, in particular a synthetic latex, while the open pore structure of this layer is maintained for water retention. Alternatively, the fibers or threads used to make the semi-finished product can be threads or fibers consisting of two components, one of the fibers or threads melting during further processing so that the remaining threads or fibers are fixed. Alternatively, the adhesion by latex can be replaced by adhesion by a thermoplastic powder. Bundles of loops can form a pattern of tops and troughs at the top as this can help remove snow from the bottom of shoes and boots. The fibers or threads used to make the semi-finished product can have a dtex value between 8 and 240 dtex, preferably a mixture, e.g. 10% 11 dtex, 20% 17 dtex, 30% 110 dtex and 40% 240 dtex. The threads or fibers can be made from a polyolefin material such as polypropylene. The fibers or threads can be made from staple fibers, monophillaments or multi-filaments, twisted or frizzed.

An embodiment of a carpet 1 according to the present invention is shown schematically in cross-section in FIG. 2 and contains the semi-finished product 4 and a non-woven layer such as a needle felt layer 6 as well as an extruded bottom layer 9.

The non-woven layer such as the needle felt layer 6 provides an additional layer that can absorb a large amount of water in a very short time while free evaporation can take place through the open pore structure. The fibers or threads used to make the non-woven layer such as the needle felt layer 6 can be between 3 and 17 dtex, preferably 9 dtex. The threads or fibers can be made from a polyolefin material such as polypropylene. The fibers can be staple fibers. The material to make the fibers or threads should preferably be synthetic, i.e. not based on coconut, cotton or other natural fibers that absorb water.

The semi-finished product 4 is attached to the non-woven layer such as the needle felt layer 6. The semi-finished product 4 can be laminated on the coated (9) needle felt layer 6, e.g. by means of heat and pressure or an adhesive material 5. The adhesive material 5 can be made from a powder of a suitable polyolefin such as LDPE or from an EVA material. The textile fleece can be processed at a temperature to melt the glue material 5 or to make it soft and sticky.

With the exception of the extruded bottom layer 9, the carpet is primarily a fibrous textile product that can absorb and retain water in internal spaces between fibers that are small enough to retain the water by surface tension effects. The extruded coating 9 is applied to the mg or underside of carpet 1 and this coating 9 is preferably a thermoplastic and anti-slip material. This extruded mg layer 9 is waterproof and has anti-slip properties.

The thermoplastic polymer surface coating 9 is extrusion applied to the bottom of the non-woven layer such as the needle felt layer 6 (i.e., removed from the top of the semi-finished product). Preferably, a thin surface layer 9, which is waterproof, is applied to the needle felt layer 6 which does not increase the stiffness of the carpet so that the end product can be rolled and laid as a normal carpet. A flexible sandwich structure is formed in this way.

A device for producing carpet comprising a carpet fleece with a textile semi-finished product including a carpet pile attached to a non-woven layer such as a needle felt layer, may comprise - an applicator unit for glueing the non-woven layer such as the needle felt lower layer and / or a textile semi-finished product; - a fastening unit for fastening the non-woven layer such as the needle felt lower layer and / or a textile semi-finished product with the glue; - an extrusion unit for the polymeric bottom layer for extrusion of a coating of the carpet fleece with a thermoplastic polymer layer.

The device may comprise a unit for making the textile semi-finished product including the carpet pile by tufting, weaving, fastening, felting or any other method known in the art. The device may further comprise a unit for coating the textile semi-finished product with a latex as well as an oven for curing the latex.

The device can be a special production line or individual components, even at different locations.

EXAMPLE

The starting point is a textile semi-finished product that comprises a non-woven layer such as a needle felt with loops at the top made of polyolefin fibers such as polypropylene fibers. The semi-finished product has a weight of 1750 g / m2 and is 4 m wide. The textile semi-finished product can be coated with a latex in the amount of 150 g / m2 to fix the loops. This semi-finished product was passed through an oven for cross-linking the latex. An EVA powder was used to attach the textile semi-finished product to a 230 g / m2 needle felt layer by powder dispersion and IR heating, optionally under pressure. The non-woven layer such as the needle felt was made of polyolefin fibers such as polypropylene fibers. The carpeting was then coated on the back by extrusion of an impermeable layer in an amount of 250 g / m2. The composition of the extrusion coating was a 100% Adflex XI EYE from Lyondellbasell. Adflex X 100 G is called a TPO (thermoplastic polyolefin) reactor. It has been developed for use in extrusion. Adflex X 100 G shows a high softness and a low modulus, with a relatively high Melt Flow Index. It contains no slip or anti-blocking agents. Further information can be found at www.polymers.lyondellbasell.com. FIRST COMPARISON TEST:

SECOND COMPARISON TEST:

Comparative test according to ISO 9073-6 12000) - liquid absorption capacity

Carpet according to embodiments of the present invention can process rapidly occurring and large volumes of water much more efficiently, such as can occur when persons wearing boots covered by snow enter a building. In addition, if water is poured into the center of a square meter of carpet, 2.05 liters of water can be absorbed within a minute before leakage occurs at the edges while the prior art carpet only takes such a short time. 1.1 liters can absorb before leakage starts to occur at the edges of the carpet.

Water resistance test

Test liquid eg water resistance perpendicular to the surface (EN ISO 11058: 2010) for the carpet embodiment of the invention: no pressure loss (Height) and result 0 m / s water flow, which means 100% impermeable.

Concluding remarks: - The ability to absorb water in the event of sudden large amounts of water is nearly double that of existing designs with a lower weight structure for water-resistant designs - Water retention capacity 10-30% higher for a lower weight structure for embodiments of the present invention compared to existing designs - High fiber content (more than 65%, more than 70%, more than 75%) compared to existing designs - Drying time per liter / m2 is the same as existing types (due to high surface to air ratio, fiber composition) or 10% or up to 20% faster when tested under typical indoor conditions of 22 ° C, 60% RH.

Claims (20)

Conclusions A method for producing a carpet with carpet pile on top and a coated felt backing, which method comprises: making a textile semi-finished product that the carpet pile made by tufting, weaving, fastening, felting or any other method known in the art contains; attaching a felt underlay to the textile semi-finished product to form a carpet fleece; and extruding a thermoplastic polymer onto the felt layer to form an impervious polymeric surface layer on the back of the carpet fleece. Method according to claim 1, wherein the felt underlay is attached to the textile semi-finished product by means of gluing. Method according to claim 1 or 2, wherein the textile semi-finished product or a part thereof and the felt backing layer comprise the same polymeric material. Method according to claim 1, 2 or 3, wherein extruded polymer is cured, cross-linked or vulcanized. A method according to any one of the preceding claims, wherein the felt backing has a gram weight of between 80 and 500 g / m2, preferably 200-250 g / m2. The method of claim 5, wherein the extruded polymer is applied to the felt backing in an amount between 30 and 600 g of dry matter / m2, and preferably 200-250 g of dry matter / m2. The method according to any of the preceding claims, wherein the felt backing is a non-woven layer. The method of claim 7 wherein the felt bottom layer is a needle felt layer. A carpet with carpet pile at the top and a felt underlayer comprising a textile semi-finished product containing the carpet pile made by tufting, weaving, fastening, felting or any other method known in the art; wherein the felt backing is attached to the textile semi-finished product to form a carpet fleece; an extruded polymer layer on the felt backing on the back of the carpeting. The carpet of claim 9, wherein the felt underlay is attached to the textile semi-finished product by gluing. A carpet according to claim 9 or 10, wherein the textile semi-finished product or a part thereof and the felt backing comprise the same polymeric material. The carpet of any one of claims 9 to 11, wherein the polymer is polypropylene. The carpet of any one of claims 9 to 12, wherein the felt backing has a grammage between 80 and 500 g / m2, and preferably 200-250 g / m2. Carpet according to one of claims 9 to 13, wherein the polymer is applied to the felt backing in an amount between 30 and 600 g of dry matter / m2, and preferably 200-250 g of dry matter / m2. The carpet of any one of claims 9 to 14 wherein there is a gradation of the pore size from the top to the bottom with a pore size decreasing towards the bottom. The carpet of any one of claims 9 to 15 wherein the extruded polymer layer has a thickness between 0.025 mm and 0.6 mm, alternatively from 0.2 to 0.25 mm. The carpet according to any of claims 9 to 16, wherein the dry fiber weight based on the total dry weight is greater than 65%, 70% or 75%. The carpet of any one of claims 9 to 17 wherein the felt backing is a non-woven layer. The carpet of claim 18 wherein the felt backing is a needle felt layer. The carpet of any one of claims 9 to 19, wherein the carpet defines a surface and is impermeable to liquid perpendicular to the surface.