Mat and mat-base assembly

Carpet base combination

This invention relates to a carpet base assembly. More specifically, the invention is directed to a carpet substrate assembly in which the attachment and detachment of a dust-removing mat to its substrate is greatly facilitated and this property is maintained for a long time. The state of the art for such a combination is defined in the characterizing part of claim 1.

A dust-removing mat is widely used as a means of preventing dust stuck to the soles of shoes from entering rooms. This dust-removing mat is placed and held in a predetermined place such as the entrance. The rug must have the property that even if it is rubbed heavily on the sole of the shoe or if many people walk in and out on it, it will not easily move out of place. In addition, the end or corner of the mat must not be easily detached or twisted on the roll.

As a means of meeting these requirements, a combination of such a dust removal mat and a mat supporting base is preferably used. Such a combination is proposed in Japanese Laid-Open Publication No. 1606/74, which comprises a sheet of a thermoplastic resin such as vinyl chloride resin having an elongate, oval or other optional shape and a mat attached to the inside of a frame-like adhesive projection formed on a removable sheet circumference.

However, if the mat is attached only to such a gripping projection formed on the periphery of the base, the mat cannot be satisfactorily prevented from moving and the corner portion of the mat cannot be prevented from twisting up. In the case of dust-removing carpets, a system is used in which the carpet is rented to the user for a specified period of time, the used carpet is washed and refurbished with an oil impregnation treatment or the like, and the refurbished carpet is re-rented to the user. When this use-repair cycle is repeated, the mat shrinks and the perimeter of the mat is difficult to fit the size of the substrate grip protrusion. In view of the above, it is preferable to provide a temporary fastening mechanism between the mat and the support base.

As such a temporary fastening mechanism, so-called magic tape, that is, a combination of a fastening element and a fiber loop element having gripping pieces attached to the base fabric. With such magic tape, satisfactory results can be achieved when soft materials such as nonwovens are combined. However, if this tape is used in the above-mentioned carpet base combination, the durability of this fastening mechanism is unsatisfactory and the suitability for repeated fastening and removal of the carpet deteriorates in a short time.

The development of a carpet base combination in which the above-mentioned drawbacks have been eliminated has now been studied, and the present invention has resulted in the main features of which appear from the characterizing part of claim 1.

The mat substrate combination according to the invention thus comprises a substrate comprising a plate formed of an elastomeric polymer, a frame-like protrusion formed on the periphery of the plate and a mat-containing portion formed on the inside of said peripheral protrusion , a dust removing mat located in the mat-containing portion and a temporary fastening mechanism for detachable carpet attachment. A fastening element comprising gripping members attached to the base fabric is attached to the substrate, a fiber loop element adhering to the gripping members is sewn to the mat, and the peripheral portion of the fastening element is fused to the plate, while the remaining portion of the fastening element is left on.

In the accompanying drawings, Fig. 1 is a sectional view showing a mat supporting a mat, Fig. 2 is a sectional view showing a dust removing mat, and Fig. 3 is a partial perspective view showing a mat substrate assembly in a state with one end of the mat removed.

The invention will now be explained in detail.

Figure 1 shows a mat-supporting substrate used in the present invention. This base 1 comprises an elongate or oval plate 2 and a frame-like projection 3 formed on the circumference of the plate 2. The plate 2 and the protrusion 3 are made in one piece from an elastomeric polymer. A concave empty part 4 is formed on the inner side of the protrusion 3, in which a dust-removing mat is placed.

As the elastomeric polymer, for example, a soft vinyl chloride resin mixture, chlorinated polyethylene, chlorinated polypropylene, ethylene-propylene rubber, ethylene-propylene-diene rubber, polyisobutylene, butyl rubber, polybutadiene, styrene-butadiene rubber, nitrile rubber, nitrile can be mentioned. The sheet of elastomeric polymer should be heat sealable. From this point of view, it is preferable to use a soft vinyl chloride resin as an elastomeric polymer.

Figure 2 shows a dust removal mat in a mat substrate connection of the present invention. This mat 5 comprises a base fabric 6, fluff yarns 7 formed by tying fibers to the base fabric 6 and flattening the upper ends of the fluff yarns 7, and a filling layer for attaching the fluff yarns to the base fabric 6. The pile yarns 7 may be spun yarns or multifilament yarns consisting of at least one of the following: cotton fibers, rayon fibers, polyvinyl alcohol fibers, acrylic fibers and nylon fibers. The base fabric 6 may be a knitted or woven fabric, a nonwoven fabric or a mesh consisting of the above-mentioned fibers, or a nylon mesh or the like. The filling layer 8 is formed by coating the reverse side of the camouflaged base fabric with an artificial rubber latex such as nitrile-butadiene rubber latex and drying the latex.

The fluff yarns 7 of the dust-removing mat adsorb the dust adhering to the soles of the shoes by sliding contact with the soles of the shoes and keep this dust on the fluff yarns 7. In order to improve the dust adsorbing and retaining effect of the fluff yarns 7, the fluff yarns 7 can be coated with a dust adsorbing liquid or the fluff yarns 7 can be impregnated with such a liquid. As the dust-adsorbing liquid, mention may be made, for example, of mineral oils, synthetic oils and vegetable oils such as liquid paraffin, spindle oil, alkylbenzene oil, diester oil and castor oil, and the water disclosed in Japanese Patent Publication Nos. 10194/78 and 37471/78.

In the present invention, instead of the above-mentioned lint-free mat, a mat formed by electrostatically attaching fibrous flocs to a base fabric can be used.

The

According to the present invention, a temporary fastening mechanism is arranged to releasably fasten the base 1 and the base 5 to each other at several points on the circumferential edge of the mat.

As shown in Figures 1 and 3, this temporary fastening mechanism comprises a fastening element 11 comprising hook-like or sponge-like gripping pieces 10 fastened to the base fabric 9 and a fiber loop element 12 which can engage the gripping pieces 10. The fastening element 11 and the fiber loop element 12 marketed, for example, under the trade name Belclo

Fastener. The gripping pieces 10 of the fastening element 11 are formed of nylon or polypropylene, and are attached to a base fabric composed of nylon fibers or other thermoplastic fibers. The opposite side of the base fabric is coated with a resin such as polyurethane to prevent the adhesive pieces from falling off. The fiber loop element 12 is formed by attaching the fiber yarns in loop formations to a similar base fabric.

In the present invention, this loop element 12 is fastened to the reverse side of the mat 5 by stitches 13, and the fastening element 11 is fastened to the plate part 2 of the base 1.

As shown in Fig. 1, the peripheral part 14 of the fastening element 11 is fastened by melting to the base plate 2, while the gripping pieces 10 are left in the central part of the fastening element 11 as they are.

According to the invention, the fusion of the circumferential part of the fastening element 11 to the base plate 2 results in a very good bonding strength (peeling strength). A bonded structure can be formed that is sufficiently resistant to prolonged repeated attachment and detachment, outdoor storage, and irrigation in water or hot water.

Since the fastening element is fused to the base plate 2, the gripping pieces 10 in the peripheral part 14 of the fastening element 11 are crushed or sealed towards the base plate. However, in the remaining part 15 of the fastening element, the gripping pieces 10 are left there, and the necessary fastening effect can be achieved between these fastening pieces 10 and the fiber loop element 12.

In fact, one of the reasons why a bond structure with excellent durability is formed between the carpet base 1 and the fastening element 11 is that the polymer forming the base plate is melt-bonded to the base fabric or to the fastening elements or filling of the fastening element. However, another reason is believed that the elastomeric polymer forming the base plate penetrates the base fabric of the fastening element 11 and the gripping members 10 of the fastening element 11 penetrate the base plate 2 through the base fabric of the fastening element 11, thus improving mechanical adhesion or

The melting of the fastening element 11 to the carpet base 1 can simply be achieved by placing the fastening element and the base on top of each other and pressing the overlapping assembly under heat with two heat sealing bars. The heating temperature may vary from the melting point of the polymer forming the base plate 2 to the melting or softening point of the base fabric of the fastening element. A pressure sufficient to crush or seal the grips 2 of the fastening element 11, which is e.g. 0.1-20 kg / cm, can be

II

Ί use. The heating is preferably performed by a high frequency heating device.

When a polyurethane adhesive is placed between the fastening element and the base to be fused, the adhesive strength of the interface can be further improved. If the filling of the fastening element consists of polyurethane resin, this resin improves the adhesive strength.

As the polyurethane resin, a polyurethane resin having end groups protected by an alcohol, phenol or amine, i.e. a heat-sensitive polyurethane resin, is preferably used.

In a preferred embodiment of the invention, the protected isocyanate and a polyol such as a polyether polyol and a polyester polyol are mixed in a stoichiometric ratio. The mixture, all components of which are preferably solid and also preferably solid at room temperature, is applied as a solution or melt at a temperature of up to 95 ° C to the back surface of the fastener, the fastener being placed in a predetermined position on the base plate so that the surface of the mixture contacts the base plate surface, and the combination of the fastening element and the base plate is heated at a temperature of 17O-19O ° C at a pressure of 0.1-20 kg / cm²by means of high-frequency heating. In this case, the dissociation of the protected isocyanate into the free isocyanate and the reaction between the reactivated isocyanate group and the polyol cause the formation of a polyurethane resin in situ, whereby the adhesive strength is improved.

For example, Collonate '⁰'AP (Nippon Polyurethane Industries Co.) obtained by reacting toluene diisocyanate with trimethylolpropane and then adding phenol to protect the remaining isocyanate groups is mixed with Placcel'⁰To 22O (Daicel Chem. Industries Co.), which consists of a polyester polyol formed by ring-opening polymerization of caprolactone in a weight blending ratio of 1: 2. To this mixture is mixed 0.33% by weight of cobalt octenoate, and the mixture is then melted at about 95 ° C. This molten mixture is applied to the back surface of the fastening element with a coating thickness of 0.1-0.8 mm. This coated fastener is placed in a predetermined position on the base so that the coated surface contacts the base and is heated by a high frequency heater for 5 seconds at about 185 ° C at a pressure of 2 kg / cm². With this method, the fastening element is completely bound to the bottom surface and cannot be removed with a release of 20 kg / cm 2.

The protected isocyanate and polyol can be applied to the back surface of the fastening element as a solution of tetrahydrofuran or methyl ethyl ketone, whereby the solvent can be evaporated after application.

Other protected isocyanates include xylenol-protected diisocyanate-diphenylmethane or 2,4-dichlorophenol-protected methyl ethyl ketone oxime and a trimethylolpropane-tolylene diisocyanate adduct.

As the second polyol, Desmophen 65O (Bayer GmbH) and Nippola 4009 or 4010 (Nippon Polyurethane Industries Co.) can be used as the polyester polyol, and Pluronic Polyol (Wyandotte Chem. Corp.) can be used as the polyether polyol. These polyols must be solid at room temperature to be preserved in all seasons.

In the carpet base assembly according to the invention, the circumferential part of the fastening element, which is important for mechanical strength or for preventing rotation on the roll, is fused to the base plate and embedded therein, while the gripping piece of the middle part of the fastening element is left there. Thus, the carpet base combination according to the invention is advantageous because the fastening effect is maintained for a long time, even if the fastening and removal step is repeated several times.