CA2594439C

CA2594439C - Floor covering

Info

Publication number: CA2594439C
Application number: CA2594439A
Authority: CA
Inventors: Gerhard Graab; Gregor Grun; Jochen Schmitt
Original assignee: Nora Systems GmbH
Current assignee: Nora Systems GmbH
Priority date: 2006-07-24
Filing date: 2007-07-23
Publication date: 2011-09-27
Anticipated expiration: 2027-07-23
Also published as: CA2594439A1; EP1884607A2; US20080020179A1; CN101113638A; KR20080009640A; KR100914809B1; CN101113638B; EP1884607A3; DE102006034646A1; DK1884607T3; EP1884607B1; PL1884607T3; ATE524626T1

Abstract

A floor covering with improved slip resistance is disclosed, including an essentially web or sheet shaped base material of an elastomeric material with an anti-slip surface including granular particles. In order to guarantee a simple manufacture and further processing of the floor covering, the granular particles consist in accordance with the invention of a polymeric material which has a hardness significantly higher than that of the elastomeric material.

Description

FLOOR COVERING
Field of the Invention The invention relates to a floor covering with high slip resistance, which essentially includes a web or sheet shaped base material of an elastomeric material with an anti-slip surface including granular particles.

Background Art A floor covering of the generic type is known from WO 03/100162. This floor covering includes a carrier made of plastic, preferably a thermoplastic polymer or a thermoplastic elastomer. To increase the slip resistance, the surface of the carrier is roughened by way of granular particles. These granular particles include preferably hard particles of quartz, silicon carbide, aluminum oxide and/or sand paper.
It is a disadvantage of this known floor covering that it is hard to cut because of the very hard particle material (corundum problem). This creates problems in the confectioning and/or further processing of the floor covering.

Summary of the Invention It is an object of the invention to provide a floor covering which is distinguished by a high slip resistance and in addition is easily and economically manufactured and processed.
This object is achieved with a floor covering in accordance with the invention with high slip resistance. The inventive floor covering includes an essentially web or sheet shaped base material of an elastomeric material. The surface of the floor covering is roughened by way of granular particles and provides an anti-slip effect. In accordance with the invention, the granular particles are made of a polymeric material, the hardness of which is higher than that of the elastomeric material.
It has been surprisingly found that these materials, although they are significantly softer than mineral particles, for example corundum, and additionally have a tendency for rounded rather than sharp corners, nevertheless result in a high slip resistance. However, in contrast to the floor coverings with mineral particles, they have the advantage of ease of manufacture and further processing. In particular, a floor covering in accordance with the invention can be cut very well.

I

It has been found that good results with respect to the anti-skid effect are achieved already when the hardness of the polymeric material is by 10 shore D higher than that of the elastomeric material.
Thermoplastics and duroplastics can principally be used as the polymeric material.
Both materials can be mixed into the base material, for example in the form of particles.
Duroplastics are less suitable for a spreading-on application, since they, just like the corundum particles known in the art, can sink into the base material during its vulcanization and resulting liquefaction.
Suitable thermoplastic polyrners for mixing with the base material are generally those, which have a melting point higher than the high temperatures occurring during later processing steps. Thermoplastic polymers with lower melting points can also be used if shear forces which could lead to a mixing of the materials are prevented during later processing steps. The melting itself of the particle material is not a problem as long as the particle droplets as such remain intact. As long as no shear forces occur, this is generally already guaranteed because of the highly different viscosities of the materials.
Preferably, semi-crystalline thermoplastic polymers are used.
In the case of spread-on particles of semi-crystalline thermoplastic material, it is even desirable that the particle material melt during the vulcanization of the base material, in order to float up to the surface of the latter. The particle droplets thereby remain intact at the surface during the vulcanization and do not sink into the liquefied base material.
After cooling, the particle droplets re-crystallize into grainy particles.
This property can be described by the location of an exothermic melting peak maximum of the thermoplastic polymeric material in a thermogram measured with a Differential Scanning Calorimetry (DSC) process. It has been found that for the elastomers and processes commonly used for the floor coverings, those thermoplastic, preferably semi-crystalline, polymers are especially suited, which in a test in the Differential Scanning Calorimetry (DSC) according to DIN 53765 have an exothermic melting peak maximum in the thermogram in a temperature range of 100 C to 250 C. If the melting point is in the temperature range given, the thermoplastic polymer during the vulcanization of the base material melts to a drop, which in the case of the spread-on particles does not sink into the base material, but floats at the surface. Subsequent to the vulcanization process, the drop at the surface re-crystallizes into a granular particle. The anti-slip properties remain intact.

2 The person skilled in the art will be able to select a respectively suitable thermoplastic polymer for a given elastomeric base material and manufacturing process without any further detailed description.
Generally, the thermoplastic polymers can be, for example, pure homopolymers, or copolymers or grafted homo or copolymers. They preferably include thermoplastic polymers selected from the group of polyofefins, modified polyolefins, semi-crystalline polyamides and/or polyesters. The polymers used can also be grafted, for example, with conventional grafting compounds such as maleic acid anhydride and/or acrylic acid, in order to improve the binding of the particles into the matrix.
A floor covering in accordance with the invention can be manufactured in different ways. For example, the granular particles can be simply spread, as mentioned above, onto the un-vulcanized blank of the elastomeric web and subsequently subjected together with the blank to a heat treatment for the vulcanization, whereby the particles are preferably melted as well.
It is also possible, as also mentioned above, to mix the granular particles into the base material of elastomeric raw material. In this variant, granular particles can be spread in addition onto the surface, whereby the process is then continued as described above.
In a further variant, the blank of the base material web made of elastomeric raw material to which the granular particles were admixed is split and subsequently subjected, optionally after spreading-on of additional particles, to a vulcanization process. In this process variant, it is also preferable to use a thermoplastic, preferably semi-crystalline polymer for the admixed particles, which after splitting of the base web also come to lie at the surface of the split web to a certain degree, which polymer in the range of the vulcanization temperature of the elastomeric base material melts, in order to also prevent a sinking of these particles into the base material during the vulcanization.
The admixing of the granular particles has the advantage compared to the spreading-on that a floor covering produced in this manner has a higher wear resistance and therefore a longer service life. Furthermore, it allows for the manufacture of a floor covering by splitting of a base web.
In the case of the admixing of the granular particles one must bear in mind that these mixing processes are generally carried out at temperatures between 100 C and 130 C. The melting temperature of the thermoplastic polymer used for the granular particles, which is defined, as described above, by the location of the exothermic melt peak

3 maximum of the material, should therefore preferably be > 130 C. Further processing steps can also be carried out at temperatures higher than the melting temperature of the thermoplastic polymer, as long as it is assured that no shear forces act on the materials at these temperatures, which could lead to a mixing of the particle material with the base material.
The requirements for the grain sizes and amount of the particle material differ depending on the type of manufacture of the floor covering in accordance with the invention. It has been found that, in the case of a spreading on of the granular particles, the best anti-slip properties are achieved when the mean grain size of the particles, measured by sieve analysis according to DIN 66165, is between 100 m and 800 m, preferably about 300 m. The anti-slip properties degrade too much at grain sizes of <100 m, while for the flooring thicknesses of 2-5mm common for elastic floor coverings, the mechanical and fire safety properties degrade too much at grain sizes >800 m.
The amount of spread on particles per surface area of the base material should be between 30cm3/m2 and 360cm3/mZ, preferably between 100cm3/m2 and 250 cm3/mZ.
The anti-slip properties decrease too much at amounts below 30 cm3/m2, while the danger exists that the mechanical and fire safety properties of the floor covering deteriorate too much at amounts above 360 cm3/m2.
In the case of an admixing of the granular particles, the mean grain size of the particles, measured by sieve analysis according to DIN 66165, should be between 100 m and 2000 m, preferably at about 500 m. At grain sizes below 100 .m the anti-slip properties again degrade too much, while the mechanical and fire safety properties degrade, as in the above cases at grain sizes above 2000 m.
The portion of the admixed particles is thereby preferably between 10% and 40%
of the volume of the base material, preferably between 14% and 25%. At a portion of less than 10%, the anti-slip properties decrease too much and the mechanical and fire safety properties degrade at a portion of more than 40%.
Potential elastomers for the base material are those which are suited for use as a floor covering. The base material preferably includes one or more of the elastomers SBR
(poly-styrol-butadiene-caoutchouc), NBR (nitrile-butadiene-caoutchouc), EPM
(ethylene-propylene-caoutchouc), EPDM (ethylene-propylene-diene-caoutchouc), EVA
(ethylene-vinylacetate), CSM (chlorosulfonyl-polyethylene-caoutchouc), VSi (silicone-caoutchouc)

4 and/or AEM (ethylene-acrylate-caoutchouc), whether sulfur cross-linked, peroxide cross-linked and/or addition cross-linked.
In a floor covering in accordance with the invention, the base material may further include generally known mineral type fillers, for example, clay, chalk, silicic acid and/or silicic chalk. These fillers are used for the purpose of adjusting the physical properties, for example the hardness and the wear of the rubber compound. Furthermore, fillers are also used for improvement of the fire safety properties. Normally, they are added in amounts of 10-70%/wt with grain sizes of <100 m.
A floor covering in accordance with the invention can be used in web or sheet form.
The invention will now be further described in the following with reference to exemplary embodiments.

Exemplary Embodiment I
275cm3 of a polypropylene powder with a mean grain size of 300 m was spread per m2 onto a web shaped base material of a sulfur cross-linkable SBR mixture.
The maximum of the melting peak of the polypropylene powder determined by DSC
according to DIN 53765 was 163 C. The web with the spread-on powder was subsequently subjected for a period of 5 min and at 180 C to a vulcanization process in a continuous vulcanization installation with a band press. The result was an elastomeric floor covering, which in a slip test with a British Pendulum Tester (BPT) achieved a slip safety value of 40 scale units upon testing with water as the glide medium.

Exemplary Embodiment II
40%/volume of the above powder was mixed at an expulsion temperature of 120 C with a sulfur cross-linkable SBR mixture. A blank of this material was calendared and split in the centre and the resulting blank was subjected for a period of 7 min and at 180 C
to a vulcanization process in a non-continuous vulcanization installation. The resulting elastomeric floor covering, achieved in the above described test a slip safety value of 36 scale units upon testing with water as the glide medium.

5 Exemplary Embodiment III
In a third variant, a web was calendared from the mixture with polypropylene powder as described in exemplary embodiment 2 and another 275cm3 of the same polypropylene powder was spread per m2 onto this web. The web was then subjected for a period of 5 min and at 180 C to a vulcanization process in a continuous vulcanization installation with a band press. The result was an elastomeric floor covering, which in the above described test method achieved a slip safety value of 40 scale units upon testing with water as the glide medium.

Comparative Example I
A web shaped base material of a sulfur cross-linkable SBR mixture analogous to Example 1, but without applied powder, was subjected for a period of 5 min and at 180 C
to a vulcanization process in a continuous vulcanization installation with a band press. The resulting elastomeric floor covering achieved a slip safety value of only 12 scale units according to the above described testing method upon testing with water as the glide medium.

Comparative Example II
In a further comparative experiment, 800g/m2 of corundum particles were spread onto a web shaped base material of a sulfur cross-linkable SBR mixture analogous to Example 1, and subjected for a period of 5 min and at 180 C to a vulcanization process in a continuous vulcanization installation with a band press. After vulcanization, the majority of the corundum particles were sunken into and enclosed by the base material.
The resulting elastomeric floor covering achieved a slip safety value of only 14 scale units according to the above described testing method upon testing with water.
The above exemplary embodiments show that a floor covering in accordance with the invention has a significantly improved slip safety value compared to a covering without anti-slip surface and a covering with spread-on corundum particles.
In addition, the floor coverings made according to exemplary embodiments 2 and with admixed granular particles of polypropylene were distinguished by a more than 20%
increased wear resistance, when compared to the base material used in exemplary embodiment 1 without corresponding admixture, according to a test carried out under ISO
9352 (Taber-Scoring) on the floor coverings of the exemplary embodiment.

6

Claims

CLAIMS:

1. A floor covering with high slip resistance, comprising an essentially web or sheet shaped base of an elastomeric material with an anti-slip surface including granular particles made of a polymeric material having a hardness at least 10 shore D
higher than that of the elastomeric material.

2. The floor covering as defined in claim 1, wherein the polymeric material includes a thermoplastic and/or duroplastic material spread onto the surface of the base material or admixed into the base material.

3. The floor covering as defined in claim 2, wherein the thermoplastic material is a semi-crystalline thermoplastic material.

4. The floor covering as defined in claim 3, wherein the semi-crystalline thermoplastic material includes those thermoplastic polymers having a melting point below or in the range of a vulcanization temperature of the elastomeric base material.

5. The floor covering as defined in claim 4, wherein the semi-crystalline thermoplastic polymeric material includes those polymers which in a temperature range of 100 C to 250 C have an exothermic melting peak in the thermogram according to the Differential Scanning Calorimetry (DSC) test according to DIN 53765.

6. The floor covering as defined in any one of claims 2 to 5, wherein the thermoplastic polymers are selected from the group consisting of polyolefins, modified polyolefins, semi-crystalline polyamides and/or polyesters.

7. The floor covering as defined in any one of claims 1 to 6, wherein the particles as spread onto the surface of the base material have a mean grain size between 100 µm and 800 µm determined by a sieve analysis according to DIN 66165.

8. The floor covering as defined in claim 7, wherein the grain size is 300 µm.

9. The floor covering as defined in any one of claims 1 to 8, wherein the particles are spread onto the surface of the base material in an amount between 30 cm3/m2 and 360 cm 3/M2.

10. The floor covering as defined in claim 9, wherein the amount is between 100cm3/m2 and 250cm3/m2.

11. The floor covering as defined in any one of claims 1 to 10, wherein the particles are admixed into the base material and the mean grain size of the particles is between 100 µm and 2000 µm measured by sieve analysis according to DIN 66165.

12. The floor covering as defined in claim 11, wherein the mean grain size is about 500µm.

13. The floor covering as defined in any one of claims 1 to 12, wherein the particles are admixed into the base material and the portion of the admixed particles is between 10 and 40 % of the volume of the base material.

14. The floor covering as defined in claim 13, wherein the portion is between 14 and 25%.

15. The floor covering as defined in any one of claims 1 to 14, wherein the base material is SBR (poly-styrol-butadiene-caoutchouc), NBR (nitrile-butadiene-caoutchouc), EPM (ethylene-propylene-caoutchouc), EPDM (ethylene-propylene-diene-caoutchouc), EVA (ethylenevinylacetate), CSM (chlorosulfonyl-polyethylene-caoutchouc), VSi (silicone-caoutchouc) and/or AEM (ethylene-acrylate-caoutchouc), when crosslinked by sulfur, peroxide and/or addition, or mixtures thereof.

16. The floor covering as defined in any one of claims 1 to 15, wherein the base material includes a mineral filler.

17. The floor covering as defined in claim 16, wherein the filler is clay, chalk, silicic acid or silicic chalk or mixtures thereof.