DE2533407A1 - Automobile carpet fabric mfg. - has molten thermoplastic resin layer to bond upper fibre layer to bottom polyurethane foam layer - Google Patents

Abstract

A process is claimed for the manufacture of carpetings, where the fabric is developed from a fibre upper layer with a thermoplastic resin inter layer and a flexible polyurethane foam bottom layer, with a layer of molten thermoplastic resin applied to the reverse surface of the fibre upper layer to be further spread with a flexible polyurethane foam or a fluid foaming mixture. The thermoplastic resin intermediate layer is cooled and the bottom layer is foamed. Designed particularly for automobile floor coverings, the process provides a simple and continuous manufacturing process without requiring adhesives, giving a material which will mould itself to the contours of the car floor.

Description

"Method of Making Carpets" The invention relates to to carpets and in particular to a process for the manufacture of the same.

In vehicles, especially cars, carpets are usually fitted, to increase comfort by reducing the noise level, by increasing the thermal To improve isolation and by increasing the elasticity of the underfoot and around a to achieve a certain decor. A well-known one Procedure for fitting of carpets on a vehicle floor consists in putting the carpet on one layer a bituminized felt that adheres to the inner metal floor. A such a procedure is generally satisfactory when the ground is straight, however, difficulties can arise if the floor is shaped or has undulations contains. In this case, it is difficult to adapt the carpet to the desired shape.

One method of overcoming this difficulty is to the back of the carpet with a thermoplastic resin such as polyethylene or polypropylene. The resin gives the carpet a certain stiffness and the ability to be brought into a shape that corresponds to the shape of the ground, by keeping the coated carpet at a temperature above the softening point of the But below the temperature at which the carpet is damaged by the heat is deformed. The quality of the carpet and its sound and heat insulation properties Can be further improved if you put a layer of felt or foam in front adding to deforming by using an adhesive.

However, this method suffers from the disadvantage that many separate Stages are required to make the finished carpet.

The invention now relates to a method of production a carpet with a fiber top layer, a thermoplastic resin intermediate layer and a flexible polyurethane foam underlayer, which is carried out by that you have a layer of molten thermoplastic resin on the back the fiber top layer, flexible polyurethane foam or a liquid foamable Mixture on the melted thermoplastic Resin interlayer applies and foaming a foamable mixture if necessary.

The inventive method reduces the number of steps that required for the production of the floor coverings, and avoids their use an adhesive, because namely the foam layer on the carpet due to the beginning melted thermoplastic resin adheres. The procedure can essentially be carried out continuously and has the additional advantage that the Melting the resin allows the resin to be prepared and used as a hot melt adhesive to use.

According to a preferred method, a mixture is used to form a liquid polyurethane foam is applied to the melted layer of the resin. The foam is allowed to form before or after the resin has cooled, however preferably at least partially during the cooling step. With this preferred one Process can improve the quality and property of the polyurethane foam continuously can be tracked and the spreading can be modified as desired. The preferred one The method is therefore more versatile and adjustable than the one with which a pre-formed polyurethane foam is used. It also avoids storage of foam and difficulties in alignment, wrinkling and even adhesion.

The fiber topsheet can be of any form of fiber construction exist, for example it can be tufted, woven, knitted or non-woven. You can, for example, made of wool, jute, burlap, cotton viscose or Acetatrayon, Nylon, polyethylene terephthalate, or any other material with a fiber nature manufactured will.

The thermoplastic resin can be any resin that has a softening point or melting point below that of the fiber top layer and below temperature in which the fiber top layer undergoes considerable decomposition during the period method according to the invention would suffer.

Similar considerations apply to the polyurethane foam layer also for the volatility of the components of the mixture. Preferred resins are polyethylene low density and polypropylene, which are unfilled, lightly filled or heavily filled could be. The resin can be applied to the back of the fiber top layer for example be applied as a hot melt or as a powder, in the latter case the Powder is then melted and made to flow, so that a cohesive Layer arises. This can be done, for example, by means of radiant heaters. Of the the latter powder route is preferred for polyethylene. The heating should be so controlled that a satisfactory resin layer without breakouts is formed. The fat the resin layer can be tailored to the end use of the carpet, but lies suitably between 700 and 7000 g / m2 for low density polyethylene and can go up to 10kg / m2 for heavily filled polypropylene.

The flexible polyurethane foam can be produced by the usual method using an organic polyisocyanate such as tolylene diisocyanate in a or more stages with a polyhydroxy compound, e.g.

a polyester, polyesteramide or polyether containing hydroxyl groups, implemented in the presence of a gas generating agent wid. Examples of gas generants are water and inert liquids with a low boiling point.

The usual surfactants such as oxyethylated phenols and organosiloxane polymers, and the usual catalysts such as tertiary amines and organic metal compounds can be used.

The flexible polyurethane foam can also contain up to 250 parts by weight of filler Contains 100 parts by weight of polyol each.

Suitable fillers are calcium carbonate, ground or precipitated Chalk, barium sulfate, washed clay, and silica powder.

The polyurethane foam can preferably have a thickness between 2 mm and 50 mm. are made, the weight preferably between 0.5 and 2.0 kg / m2 and the density between 15 kg / m3 and 500 kg / m3, preferably between 15 kg / m3 and 200 kg / m3. However, the foam is preferably produced in situ, namely by spreading the liquid foaming mixture, for example by Spraying onto the molten thermoplastic resin. It can be a doctor knife used to make the spreading more even if needed. A preformed foam can be embossed onto the molten resin prior to spreading or after spreading the foam, for example with a roller, be embossed.

The thermoplastic resin can be left to cool naturally, or cooling can be accelerated by blowing cooling air onto the carpet though the resin through the fiber top layer and the polyurethane bottom layer is partially isolated.

After cooling, the carpet can be rolled up and stored or in Pieces of desired size cut and then be shaped. But it can also be shaped immediately after cooling. If alternatively the foam is made before or when the resin is significantly cooled If a pre-formed foam is used, the carpet can then be left to cool before cooling cut and deformed, then of course cooling and reheating is avoided. The molding can be carried out at a temperature at which prevent substantial damage to the fiber top layer and the foam bottom layer will.

The invention is explained in more detail by the following example, where Reference is made to the accompanying drawings.

In the drawings: FIG. 1 shows a section through a through the carpet produced by the process of the invention; and FIG. 2 is a schematic Representation of a device for carrying out the method according to the invention.

The carpet produced by the process of the invention from Fig. 1 has a fiber top layer 1, which has tuftings 2, an intermediate layer 3, which is made of a thermoplastic resin, and a flexible polyurethane foam base layer 4th

In the device of Fig. 2, a conveyor 6 is provided, which is shown in Arrow direction promotes. There is a hopper near the front end of the conveyor and a distribution unit 7 arranged for resin powder, whereupon a group of radiant heaters X and a spray gun 9 for the polyurethane foaming mixture connects. The spray gun has a head for mixing the components of the Foaming mixture. Another group of radiant heaters 17 is provided, to aid foaming. The device is provided with a cooling chamber 10 and a cutting device, in a suitable manner a guillotine 11 equipped. The distribution unit, spray gun and guillotine extend transversely across the width of the device or can be traversed across the width of the device will. The radiant heaters are expediently fixed and extend across the width of the device.

A drum topsheet 12, which during the illustrated process is the lowest layer, is passed through the device on the conveyor 6, with the back 13 facing up. Low density polyethylene powder is sprinkled on the back of the funnel and of the distribution unit 7 and the powder is melted under the influence of the radiant heaters'8 and for Brought a layer of melted thermoplastic Resin 15 is produced. A polyurethane foaming mixture is applied through the spray gun 9 applied to the molten resin, its foaming by radiant heaters 17 is supported while the molten resin is already partially cooling. Further cooling and solidification takes place in the cooling chamber 10.

The cooled carpet can then be cut using the cutter X after Wish to be cut into pieces.

A typical carpet that is under Made using the above device was a tufted carpet. The tuftings were made of nylon-6,6 and had a synthetic fiber back. Low density polyethylene was melted at 1100C so that it had a polyethylene content with a density of 1300 g / m2 was obtained. The polyurethane foaming materials were fed in two streams to the mixing head of the spray gun (parts by weight): Stream A consisted of tolylene diisocyanate (50 parts, for example "Suprasec't EN; Isocyanate index 105).

Stream B consisted of polyols (50 parts), water (0.5-6.0 parts, typically 3.0 parts), triethylenediamine (0.1-1.0, typically 0.1 part), Silicone L-520 (0.5-2.0 parts, typically 1.5 parts), stannous octoate (0.1-1.0 Parts, typically 0.5 parts). Each stream was given equal weight to the mix head fed to the spray gun.

A similar carpet could be made using polypropylene that was applied as a melt, the radiant heater 8 omitted and the funnel 7 was replaced by a melt extruder head.

The polyurethane foam-forming mixture was applied to the polypropylene while it was still warm upset.

Similar carpets were also made using the following mixes In each stream (weight) produced: CURRENT A 1 2 3 "Suprasec" EN 24.0 50.0 10.0 CURRENT B "Daltocel" T56-60 - - 100 "Daltocel" T48-35 100 100 water 1.8 3.9 0.1 "Daltogen" DEA - - 1.5 "Dabco" - 0.15 "Silcocell" 380 1.0 1.0 2.0 barium sulfate 50 100 tin (II) octoate 1.0 1.5 0.25 china clay - - 50 foam density (kg / m3) 245 150 221 "Suprasec", "Daltocel", "Daltogen", "Silcocell" are trademarks of Imperial Chemical Industries Limited.

"Dabco" is a trademark of Houdry Process Corporation.

Claims (12)

PATENT CLAIMS Process for the production of carpets with a fiber top layer, a thermoplastic resin intermediate layer and a flexible polyurethane foam base layer, characterized in that there is a layer of molten thermoplastic Applying resin to the back of the fiber layer, flexible polyurethane foam or spreads a liquid foaming mixture on the molten thermoplastic resin, the thermoplastic resin intermediate layer cools and optionally a foamable one Foam mixture. 2. The method according to claim 1, characterized in that the layer from the molten thermoplastic resin on the back of the fiber layer Wlrd formed by applying the resin as a powder on the back and then the powder to produce a cohesive molten resin slide melts. 3. The method according to claim 2, characterized in that as a powder Polyethylene is used. 4. The method according to claim 1 or 2s, characterized in that the Resin is made on the back of the fiber layer by having a hot Spreads melt of the resin. 5. The method according to any one of claims 1 to 4, characterized in that ,. that a resin is used with a filler 6. Procedure according to one of claims 1 to 5, characterized in that the polyurethane foam is preformed will. 7. The method according to claim 6, characterized in that the foam has an embossing. 8. The method according to any one of claims 1 to 5, characterized in, that a liquid polyurethane foaming mixture is applied to the molten resin layer is spread. 9. The method according to any one of claims 1 to 8, characterized in that that the polyurethane foam is embossed. 10. The method according to any one of claims 1 to 9, characterized in, that the polyurethane foam contains a filler. 11. Apparatus for producing a carpet with a fiber top layer, a thermoplastic resin intermediate layer and a flexible polyurethane foam underlayer, characterized in that it comprises the following parts: a device for manufacturing a molten thermoplastic resin on the back of the fiber layer, means for spreading a flexible polyurethane foam on the molten one Resin and means for cooling the resin intermediate layer. 12. The device according to claim 11, characterized in that it n; at least has a spray head that contains a chemical mixture to form a applies flexible polyurethane foam to the resin. L e r s e i t e