DE2824739A1 - ANTISTATIC FLOOR COVERING - Google Patents

Abstract

The floor covering, preferably consisting of polyvinyl chloride, consists of an upper layer and of a thin lower layer. The upper layer has a dissipation resistance of 10<6> to 10<8> ohms, while the lower layer has a dissipation resistance of 100 to 500 ohms. As a result of this relatively high conductivity of the lower layer, sudden dissipation of electrostatic charges which are formed in the upper layer is achieved, the lower layer needing to be earthed only at the edges and it being possible to dispense with the normal laying of a copper network under the floor covering.

Description

AntEstatic flooring

Registered all: (A Start of patent term: The present invention relates to a floor covering with an anti-static effect made of rubber or plastic, and has the purpose of preventing electrostatic discharges from occurring in one to derive certain resistance range safely to earth.

For example, it is known rubber or polyvinyl chloride coverings by mixing in certain special soot or other conductive parts electrically to make conductive. The electrical conductivity of these floor coverings lies in the Rule between 104 - 106 Ohm leakage resistance to earth. Such Coverings are used in operating theaters in hospitals, where the most stringent requirements the electrical properties are required to avoid any risk of explosion, e.g. turn off when handling ether.

For areas of application in which such high conductivity is not required is, for example, in rooms for computer systems, where a leakage resistor from 106 to 108 ohms, floor coverings are made with chemical agents, so-called Antistatic agents added, which give the flooring the desired conductivity. For the applications where such coverings are used is greater conductivity from top to bottom not required, so that you get the higher economic No effort is required to further reduce the leakage resistance.

There are different areas of application for rubber and synthetic floor coverings with different strict requirements for the antistatic properties.

The requirements that are made of a good floor covering are partly completely contrary, so that a middle ground is kept in the production that meets both requirements as well as possible. These requirements consist on the one hand in the highest possible conductivity to electrostatic To avoid charging, while on the other hand the highest possible isolation for the purpose Avoidance of fire closures is desired.

EleXctrostnt; ischet charges produced around the derivation, unFt A network of copper wires on the underside is made possible for such coverings appropriate. Naturally, this requires a special effort of manipulation. To get a sufficiently high transverse conductivity and every point To capture the covering immediately, the wire mesh must be arranged accordingly tightly which is also unfavorable on the cost side.

The aim of the invention is to create a floor covering that, although has an extremely high transverse conductivity, but overall a leakage resistance to earth between 109 and 108 ohms.

This is achieved according to the invention in that the floor covering has a lower layer made of a particularly conductive mixture with a leakage resistor from about 100 to about 500n and an upper layer has a leakage resistance of about 10 to about 108 Ω.

The conductivity of the upper layer is according to the invention by a Content of antistatic active chemical substances reached. Such Active ingredients can be alkyl sulfates, alkyl sulfonates, quaternary nitrogen bases, ethoxylated Fatty amines, alkylolamines, phosphoric acid esters, polyglycol esters and the like (see magazine Gtunmi, Asbest, Kunststoffe No. 2, 4, 5 and 6 1973; Gentner Verlag, Stuttgart; items "Antistatics" by Dr. S. Riethmayer). However, it is also possible to use conductive carbon blacks to be used, which is also often done with rubber flooring, since color effects that are possible with plastic coverings, but have to do without it anyway.

The IConstrulction according to the invention has the consequence that in the upper Electrostatic charges generated by the layers over the entire surface particularly conductive layer in contact with the upper layer is derived can be, with a complex manipulation when laying the floor covering is not required, but the floor covering may only be loosely laid and the lower layer can be grounded on one side.

Floor coverings that are used, for example, in the aforementioned IT area, do not require a bleeder resistance of the top layer that would be less than 106 ohms, since this would not bring any additional benefit from a technical point of view. It is therefore used in this area preferably floor coverings made of plastic, in particular polyvinyl chloride, their upper Layer has a leakage resistance of about 106 to about 108 ohms. Achieved thereby you not only have a technically satisfactory solution, you also have the option The color and pattern of the surface of the floor covering are largely to be selected.

The grounding can expediently take place in that the lower Layer over a metal insulation conductor with an earth line in a Vcrbindulig This metallic conductor can be attached along only one edge of the flooring and, if necessary, by means of a conductive adhesive on the underside of the covering be fixed.

A particularly favorable discharge of electrostatic charges can can be achieved when the thickness ratio of the upper layer to the lower is about 10: 1. It is also advantageous if the electrical conductivity of the lower layer is achieved by adding carbon black, so that even with a small thickness a high conductivity can be achieved.

Example 1 A particularly advantageous blend of the above antistatic Layer is made up of the following components: Parts E- PVC K 70 50 E- PVC K 65 50 ketone resin 5 epoxy softener 10 die (2 sthyl-hexyl) phthalate 29 Zn stearate 1.2 Cd-Ba stabilizer solid 1.2 Cd stabilizer liquid 0.7 Chelator 0.8 chalk 50 stearic acid 0.3 antistatic e.g. 5.0 Tebestat JK 12 Cyastat ts example 2 S- PVC K 70 100 ABS powder 11 Di- (2 ethyl-hexyl) phthalate 35 Epoxidized soybean oil 2 Cd-Ba stabilizer solid 1.2 Cd stabilizer liquid 0.7 Chelator 0.8 chalk 50 Stearic acid 0.3 Antistatic e.g. 10 Tebestat JK 22 Example 3 The following composition for the lower layer with a leakage resistance of about 100 to about 500 R, is particularly advantageous for use as the backing of a floor covering: Parts E-PVC 100 Cd stabilizer liquid 1.0 Cd-Ba stabilizer solid 2.0 Zn stearate 0.4 chelator 1.6 Pb stabilizer chalk 50 conductive special carbon black pasted with Di (2-ethyl-hexyl) phthalate in 50% concentration 146 e.g. Corax L The determination the leakage resistance takes place in accordance with Ö -Norm 5209 by using a circular measuring electrode Made of brass with an area of 20 cm2 without a protective ring with a minimum load of 400p is used. Place tap water on the center of the surface of the sample Moistened blotting paper of 50 mm diameter placed and the measuring electrode over the entire surface set on. Between the graphite electrode on the underside and the measuring electrode the electrical resistance is measured on the top.

The floor covering according to the invention can by the following method in are advantageously produced: In a trough mixer are polyvinyl chloride and powdery stabilizers intimately mixed with one another for 5 minutes.

During this, the necessary dyes are stored in a mixing bucket and the necessary amount of antistatic in part of the total plasticizer and the liquid stabilizers with a basket stirrer.

After completion of the mixing process, the dye, stabilizer and antistatic mixed plasticizers as well as the residual plasticizers for the basic mixture added and mixed for 1D min.

Then the filler required according to the recipe is added and mixed for 10 minutes. A powdery mixture is obtained.

The pattern consists of a basic color, a light and a color dark marbling component.

The mixtures are separated according to marbling components on rolling mills at temperatures between 1600C and 1900C, preferably 1800C to homogeneous, approx. 5 mm thick rolled heads processed.

The material running on the rolling mills is used for marbling equal amounts of the basic and marbling components are taken, Rolled up into a so-called doll, sent over another rolling mill and then on the calender at temperatures between 1700C and 1800C to the raw flooring layer calendered.

The one made for the conductive foil for the gap coating Mixing is carried out on a 4-roll calender with a suitable kneader connected upstream or Gelimaten and Walzlser1ten at temperatures from 180oC to 190 ° C, preferably 1800C processed into a 0.20 mm thick, highly conductive film.

For connecting the flooring layer and the conductive backing coating, hereinafter referred to as "doubling", is a continuously operating doubling line used.

For a covering with a total thickness of 2.2 mm, three, 0.70 mm thick floor covering layers and a 0.20 mm thick conductive layer relined.

The conductive layer is applied so that it is after the doubling process represents the back of the covering. The doubling of the layers is done with a Temperature from 1500C to 1800C, preferably 1700C carried out.

The finished covering sheets are slowed down again in a tempering tunnel heated to approx. gOOC, left at this temperature for a certain time and then slowly cooled to room temperature. This system works continuously.

- patent claims -

Claims (5)

P a t e n t a n s p r ü c h e, 1. Floor covering with antistatic Effect, characterized in that it has a lower layer from a special conductive mixture with a leakage resistance of about 100 to 5ooQ and an upper So a layer with a leakage resistance of about 106 to 108 #. 2. Floor covering according to claim 1, characterized in that the upper Layer has a leakage resistance of about 10 6 to about 10 8R. 3. Floor covering according to claim 1 or 2, characterized in that the lower layer is connected to an earth line via a metallic conductor stands. 4. Floor covering according to claims 1, 2 or 3, characterized in that that the thickness ratio of the upper layer to the lower layer is about 10: 1. 5. Floor covering according to one of the preceding claims, characterized in that that the electrical conductivity of the lower layer by a content of soot is achieved.