WO1999004085A1 - Conductive patterned linoleum floor covering and method for producing the same - Google Patents

Abstract

The invention relates to a linoleum-based electrically conductive floor covering. The linoleum wear layer has an irregular pattern made up of differently coloured areas. Said differently coloured areas are clearly defined in relation to each other and each has a different degree of electrical conductivity. The invention also relates to a method for producing the inventive floor covering.

Description

"Conductive, patterned linoleum flooring and process for its manufacture"

description

The present invention relates to a linoleum-based floor covering which is electrically conductive and in which the linoleum wear layer has an irregular pattern, e.g. a marbling, from different colored areas. The differently colored areas are sharply defined from each other and have different electrical conductivity.

The production of sheet-like floor coverings based on linoleum (hereinafter also referred to as linoleum floor coverings) takes place in the manner. that initially all components, such as binders (so-called Bedford cement or B-

Cement from a partially oxidized linseed oil and at least one resin as a tackifier), at least one filler and at least one colorant in a suitable mixing device, e.g. a kneader, rolling mill or extruder, to form a homogeneous base mixture (mixed mass). Soft wood flour and / or cork flour (with simultaneous

Presence of wood flour and cork flour typically used in a weight ratio of 90: 1 0) and / or chalk, kaolin (china clay) and heavy spar. The mixed mass usually contains at least one colorant, such as a pigment (eg titanium dioxide) and / or other customary colorants based on inorganic and organic dyes. A typical linoleum composition, based on the weight of the wear layer, about 40 wt .-% binder, about 30 wt .-% of organic fillers, about 20 wt .-% of inorganic (minerali ^¬ cal) fillers and ca. 10% by weight of colorant. Further, in the mixing mass ^¬ conventional additives such as processing aids, antioxidants, UV-stabilization catalysts, lubricants and the like may be contained, the dependence of the in

Can be selected. To produce a single-color linoleum floor covering, the mixed mass obtained in this way is fed to a rolling mill (for example a calender) and pressed onto a carrier material under pressure and a temperature of usually 10 to 150 ° C. (depending on the recipe and the process technology). A material based on natural and / or synthetic fabrics or

Knitted fabrics and textile materials are used. Examples include jute fabrics, blended fabrics made of natural fibers, such as cotton and rayon wool, glass fiber fabrics, glass fiber fabrics coated with adhesion promoters, mixed fabrics made of synthetic fibers, fabrics made of core / sheath fibers with e.g. a polyester core and a polyamide sheath. For example, a coating of the glass fibers made of a styrene-butadiene latex can be used as an adhesion promoter for glass fiber fabrics.

When the mixed mass is pressed onto the carrier material, the rolling mill (e.g. the roll spacing of a calender) is adjusted so that the resulting floor covering web is given the desired layer thickness. In the case of linoleum floor coverings, the total thickness is usually about 2 mm to about 6 mm, in particular about 2 mm to about 4 mm.

If a colored patterned floor covering is to be produced, mixed or base materials of different colors are first produced separately, rolled into skins and granulated. Thereafter, different colored granules are mixed together and then fed to the rolling mill (e.g. a calender) and pressed either directly onto the carrier fabric or onto the carrier fabric precoated with a plain-colored mixture and / or a corkment layer.

In special cases, the mixture of differently colored granulates prior to application to the substrate material in rolling mills to striped skins ver ^¬ is stretched to 90 ° C twisted laid on each other and calendered by friction and pressed onto the Trägermateriai, with the known, modeled on the natural marble Sample images result.

Since thus obtained linoleum floor covering web supply no process for the further Ferti ^¬ and comprises the use of sufficient tensile and compressive strength, this is only achieved in a subsequent ripening process by further crosslinking the binder in ripening ovens or ripening chambers at a temperature of about 40 ° C. to 100 ° C. for a period of from a few days to about 7 weeks.

A conventional linoleum floor covering produced in the manner described above has a relatively high electrical resistance (electrical discharge resistance R _A according to DIN 51 953 of approximately> 10 ^{1 1} Ω. Therefore, such a linoleum floor covering cannot be used in rooms whose operating principles include that the floor covering certain electrical

Abieit values must have, such as operating rooms of hospitals, laboratories and computer rooms. For such applications, it is known to reduce the electrical resistance of the linoleum flooring by adding electrically conductive fillers such as e.g. Reduce special blacks or metal powder. Additions of special carbon black, on the one hand, have the disadvantage, however, that the use properties of the linoleum flooring change because of the relatively large amount of carbon black to achieve sufficient electrical conductivity, i.e. deteriorate. On the other hand, when adding carbon black to the linoleum mixture, there are practically no more color options. Even when using metal powders to improve the electrical conductivity, the color design options are considerably limited and, in addition, there are changed properties in the mechanical behavior as well as an increase in weight and a significantly reduced thermal insulation of the floor covering.

An object of the present invention is therefore to provide a suitable as a floor covering linoleum sheet, which has a lower electrical leakage resistance R _A, as a conventional linoleum floor covering, Special into ^¬ an electrical leakage resistance _RA of <10 ⁸ Ω (according to DIN 51,953) and despite the addition of electrically conductive fillers a color Gestal ^¬ tung with sharp contours color areas having.

Another object of the present invention is to provide a method ben with which such a linoleum flooring can be produced.

These tasks are solved with the objects characterized in the claims.

It has been shown in the context of the present invention that a linoleum floor covering with a desired electrical conductivity and an attractive, colored pattern can be obtained in the following way:

As before, mixed masses are produced from the components required for linoleum floor coverings. In addition to the non-conductive mixed masses (so-called "normal" or "N" linoleum), at least one conductive mixed mass (so-called "conductive" or "LG" linoleum) is produced by adding carbon black and / or metal powders. As filler material for "N" linoleum, e.g. Chalk, kaolin, talc, wood flour, cork flour, quartz flour, dolomite, silica, heavy spar and slate flour or any mixture thereof can be used, the proportion of the fillers, based on the total amount of the mixture, being 15 to 80% by weight, preferably 50 to 70% by weight, particularly preferably 60 to 65% by weight.

According to the conventional procedure, the mixes for the production of plain-colored linoleum floor coverings are each fed directly to a rolling mill or for the production of multi-colored floor coverings are first processed into rolled skins, which are then comminuted, for example granulated, and only then is a mixture of differently colored particles or granules fed to the rolling mill ^¬ led. When calendering under friction, this creates an irregular pattern and, as mentioned above, it is possible to achieve a pattern based on natural marble. If the mixture of granulate particles also contains granulate which contains conductive filler material, the result is a linoleum floor covering whose electrical dissipation resistance is reduced.

However, with this conventional procedure, it is not possible to achieve sharp- ^edged patterns in which the colored areas and the areas containing the conductive filler material are sufficiently clearly delimited from one another. Rather, there are paths in which the pattern is "smeared" and practically no or only a few areas with pure colors are present.

This disadvantage can be avoided according to the invention by producing rolled skins from non-conductive ^" mixed compound (" N "linoleum) and conductive mixed compound (" LG "linoleum), then superimposing (duplicating) these skins and bringing them into intimate contact and only then comminuted together to form particles that consist of two different parts that adhere to each other, one part made of a non-conductive compound and the other part made of a conductive compound.

The multilayered composite of the rolled skins can be used to produce the particles e.g. granulated, cut, broken or ground. The composite is preferably processed into granules.

If these particles or the granulate from parts of different mixed mass are then fed to a rolling mill, such as a calender, and rolled onto a support, surprisingly, an irregular pattern results, in which the differently colored, in each case connected, but also separate areas of conductive and non-conductive material are clearly delineated from each other and the colored areas remain practically pure. These colored areas are surrounded by the mixed mass containing the conductive filler material and therefore more or less dark to black in color.

In addition to the improved optical design options, there is also the advantage that the conductive mixed mass can contain a comparatively large amount of conductive filler material, such as carbon black and / or metal powder. This can significantly reduce the electrical leakage resistance of the flooring and still leaves the option of colored design.

Any natural or synthetic dyes and inorganic or organic pigments, alone or in any combination, can be used as colorants. be used.

The colored areas can be both plain and color-patterned. For multi-colored floor coverings, e.g. differently colored granules are calendered to form a fur or differently colored granules are sprinkled onto a single-colored or multi-colored rolled skin which has already been produced and are again calendered or pressed. It is also possible to produce several rolled skins from a single-colored but different color and to double or triple them with the fur made from conductive material and then to granulate them. The number of skins and their color and electrical properties are not specified. One or more fur (s) made of non-conductive mixed mass of the same or different color or color pattern can be combined with one or more fur (s) made of conductive mixed mass in any order and comminuted, preferably granulated. It is also possible to produce a plurality of rolled skins with conductive fillers, only one type of conductive filler being contained in each rolled skin.

The size, shape, color and pattern of the non-conductive can be varied by varying the thickness of the fur, the number of layers, the size of the granules, the arrangement of the fur, etc.

Segments or areas as well as the layer thickness of the conductive areas or borders are influenced within wide limits, which results in a variety of optical design options.

It is preferred that the concentration is as high as possible of conductive filler material in the relevant mixed mass, since in this case the film thickness of the coat can be extremely made small of conductive mixed mass, and thus very thin borders or contiguous regions of routing ^¬ enabled material finished flooring result.

In general, the amount of conductive filler depends on the desired conductivity of the floor covering and the desired pattern and must be set accordingly. When carbon black is used as the conductive material, the concentration, depending on the type of carbon black, is about 3-30% by weight, preferably about 4-1 8% by weight, based on the weight of the conductive mixed mass. As soot, for. B. Printex ^® XE 2 (Degussa AG) or Vulkanruß ^® XC 72 (Cabot GmbH) or one or more other commercially available carbon blacks.

When using metal powder as the conductive material, the concentration is about 1.5-40% by weight, based on the weight of the conductive mixed mass. The amount used depends on the density and particle size of the metal powder. As a metal powder z. B. magnetite powder, aluminum, bronze and

VA powder can be used. Any mixture of carbon black and one or more metal powders and a single metal powder or a mixture of several metal powders can also be used. The quantity ratios for mixtures of carbon black and metal powder should be chosen so that the resistance to drainage R _{A of} the floor covering, which contains conductive and non-conductive mixed linoleum, is less than 10 ⁸ Ω (DIN 51 953).

The invention is explained in more detail with the aid of the examples below, these examples only serving to illustrate, but are in no way restrictive.

example 1

First, a non-conductive, plain-colored linoleum mixture is made by mixing all components homogeneously in an internal mixer. As

Filler, wood flour, is used in an amount of 30 wt .-%, based on the entire ge ^¬ mixed mass. Titanium dioxide is added as a pigment in an amount of 10% by weight, based on the weight of the mixed mass. A rolled skin with a layer thickness of approx. 3 mm is produced from this mixed mass using a calender.

In the same way, a rolled skin is made of conductive material, in which 10% by weight wood flour through 5% by weight carbon black with the trade name Printex ^® XE 2 of Degussa AG is replaced.

The two skins are relined and then granulated. The granulate particles have a length of approx. 1 cm, a width of approx. 6 mm and a thickness of approx. 6 mm. The two parts made of conductive and non-conductive mixed mass that adhere to one another can be clearly distinguished.

With the help of a calender, the granulate is rolled into a web which is applied to a jute fabric as a carrier. The web is then matured in a ripening chamber to the finished floor covering in the usual way.

The floor covering has a non-uniform pattern of differently colored areas, the black, contiguous areas containing the soot being delineated by the bright areas made of non-conductive mixed mass. The flooring has an electrical

Leakage resistance R _A of <10 ⁸ Ω (according to DIN 51 953).

Example 2

Example 1 is repeated, with the difference that the plain-colored rolled skin made of non-conductive mixed mass is replaced by a two-colored rolled skin which is doubled with the rolled skin made of conductive mixed mass and then granulated. The electrical properties of the floor covering obtained correspond to that of Example 1, the areas made of non-conductive material being irregularly patterned in color.

Example 3

Example 1 is repeated, with the difference that the layer thickness of the non-conductive rolled file is 4 mm and the layer thickness of the conductive rolled file is 2 mm. Further, as carbon black Vulkanruß ^® XC 72 of Cabot GmbH in a ration of 1 Kon ^¬ center 8 wt .-%, based on the weight of the mixed mass, is introduced ^¬. The floor covering obtained has an electrical leakage resistance R _A of <10 ⁸ Ω (according to DIN 51 953). The areas made of conductive material are thinner than in the floor covering of example 1, as a result of which the floor covering appears lighter overall.

Example 4

Example 1 is repeated, a composite being produced from three rolled skins. A skin made of non-conductive mixed material with a layer thickness of 2 mm is used as the upper and lower rolled skin, the upper skin

Contains 1 0 wt .-% titanium dioxide as a pigment and the lower skin 1 wt .-% phthalocyanine blue (BASF AG) as a pigment.

As the middle coat, a coat made of conductive mixed material with a layer thickness of 2 mm is used, as described in Example 1. The electrical leakage resistance R _{A of} the floor covering obtained is <10 ⁸ Ω (according to DIN 51 953). The colored areas have sharply contoured areas of different colors and areas are present which essentially only show one of the two colors. All colored areas are also sharply defined from the dark, conductive areas.

Example 5

A 4-layer composite of rolled skins is produced, in the following order from top to bottom:

Non-conductive rolled skin with 10% by weight titanium dioxide as pigment; Layer thickness 2 mm.

Conductive rolled skin according to Example 1; Layer thickness 2 mm. Non-conductive rolled skin with 10 wt .-% Ti0 ₂ as a pigment; Layer thickness 2 mm.

Conductive rolled skin with magnetite powder in a concentration of 35% by weight, based on the weight of the mixed mass; Layer thickness 2 mm. The floor covering obtained has an electrical leakage resistance R _A of <1 0 ⁸ Ω (according to DIN 51 953) and the different areas made of conductive and non-conductive material are sharply demarcated. Furthermore, differently colored areas of conductive material containing carbon black and aluminum powder can be distinguished.

Claims

Expectations 1 . Linoleum-based flooring which (in accordance with DIN 51 953) is electrically conductive and in which the linoleum wear layer has an irregular pattern of differently colored areas, the differently colored areas being sharply delineated from each other and each having a different electrical conductivity . 2. Floor covering according to claim 1, wherein one of the differently colored areas is electrically conductive and the other is essentially electrically non-conductive. 3. Floor covering according to claim 1 or 2, wherein the floor covering has an electrical discharge resistance R _A of <1 0 ⁸ Ω (DIN 51 953). 4. Floor covering according to one or more of claims 1 to 3, wherein the electrical conductivity is brought about by electrically conductive filler. 5. Floor covering according to one or more of the preceding claims, wherein the electrically conductive filler is carbon black and / or metal powder. 6. Floor covering according to one or more of the preceding claims, the essentially electrically non-conductive Areas are plain or multi-colored patterned. 7. Linoleum-based granules, the granulate particles each having at least two parts adhering to one another, at least one part consisting of an electrically conductive linoleum mixture with an electrical resistance R _A of <1 0 ⁸ Ω (according to DIN 51 953) and at least one Part made of electrically non-conductive Linoleum mixed mass with an electrical leakage resistance R _A of> 10 ¹⁰ Ω (according to DIN 51 953). 8. A method for producing a linoleum-based floor covering according to one or more of claims 1 to 6, comprising the following steps: -Making a mixed mass containing the Bedford cement, at least one electrically non-conductive filler and at least one colorant; Processing the mixed mass with the help of a rolling mill to a rolled skin; Production of a further mixed mass containing the Bedford cement, at least one electrically conductive filler and possibly one or more colorants; Processing the further mixed mass with the help of a rolling mill to a rolled skin; surface connection of the rolled skins; Crushing the sheet-like composite of the rolled sheets to be particles ^¬ certain size and shape; Feeding the crushed particles to a rolling mill; and applying the rolled mass to a carrier material. 9. The method according to claim 8, wherein two or more rolled skins made of non-conductive linoleum mixed mass are connected to one or more rolled skins (s) made of electrically conductive linoleum mixed mass and then the composite is comminuted. 10. The method according to claim 8 or 9, wherein the rolled skins have the same or different layer thicknesses. 1 1. Method according to one or more of claims 8 to 10, wherein the electrically conductive filler is carbon black and / or metal powder. 1 2. The method according to one or more of claims 8 to 1 1, wherein as an electrically conductive filler at least 1 carbon black in an amount of 3-30 wt .-% or at least 1 metal powder in an amount of 1, 5-40 wt .-% %, based on the weight of the electrically conductive linoleum mixture, or a mixture thereof, is used. 1 3. The method according to one or more of claims 8 to 12, wherein the composite of the rolled skins is crushed into granules. 1 4. The method according to one or more of claims 8 to 1 3, wherein the or the rolled skin (s) made of non-conductive linoleum mixture ^¬ mass is plain-colored and / or patterned in itself.