DE2739189A1 - Lightweight floor tile - using wood shavings bonded with magnesite and covered with thin layer of anhydrite - Google Patents

Abstract

The parent patent describes a multilayer floor covering panel or tile with a low wt. and pref. using two layers (a, b) where layer (a) consists of pressed wood-, wool or - shavings bonded via magnesite or cement. Layer (b) consists of anhydrite and water. The improvement is that layer (b) also contains tributyl phosphate (TBP) as an antifoamant. Layer (b) pref. contains 5 wt % TBP w.r.t. the wt. of anhydrite. Layer (b) is pref. made of synthetic anhydrite contg. by wt. 1-2% CaF2, 0.7-1.4% CaO, 0.1-8% BaSO4, 0.2-0.5% Fe- and Al- oxides, 0.8-1.5% water, remainder CaSO4. Layer (b) pref. also contains 1-3% liquefier w.r.t. the wt. of anhydrite, and also fly ash or synthetic stone as a filler. As compared with the parent patent, a further redn. in mfg. cost is obtd. and the prodn. of the tiles is simplified.

Description

Screed

The invention relates to a screed serving as a floor covering, according to patent application P 24 21 170.9-25.

Screeds are known to be seamless floor coverings made of binders and Supplements, the individual screed floors in particular according to the type of binder can be differentiated, e.g. as cement screed, anhydrite screed. Screeds will be applied to concrete substrates, which should be tight, rough and free of cracks.

They are particularly suitable as industrial floors.

After the main registration, in order to reduce the high labor costs, it has been proposed to use lightweight panels for the screed, at least on one of their surfaces with a relatively thin layer of anhydrite compared to the thickness of the panel, preferably up to 1 cm thick, and that the anhydrite layer is a mixture from pure anhydrite binder and water, or this layer from pure gnhydrite mortar and a mixed component of the anhydrite stimulators, e.g., calcium oxide. It is Likewise suggested by the applicant that the proportion of this Mixed component is relatively smaller compared to an anhydrite binder for others Soils, is, especially with a part of anhydrite, the proportion of the mixed component, e.g. sand or the like.

is much smaller than 2.5 parts. The diameter should be the lightweight board is about 2.5 cm and its coefficient of thermal conductivity t (Kcal / h x degrees) is 0.08, with an additional layer known per se from under the slab floor Foam sheets or bulk goods, in individual cases, should be available. Under the technical building material anhydrite, synthetic anhydride is used almost exclusively, which is obtained from residues that are used in a large-scale production process of hydrofluoric acid, and the naturally occurring fluorspar is heated. Solid calcium sulphate is obtained here. The one obtained synthetically from residues Anhydride is a whitish-gray, non-flammable powder with the following composition: Calcium sulfate (0aS04) 90 - 95% calcium fluoride (CaF2) 1 - 2 o, o calcium oxide (Ca) 0.7 - 1.4% water (H20) 0.8 - 1.5% barium sulfate (3aS04) 0.1 - 0.8% iron and aluminum oxide 0.2 - 0.5 ° h The invention is based on the object of producing lightweight building boards to accelerate and cheaper with an anhydrite layer.

According to the invention, it is surprisingly proposed for this purpose, an anhydride for the production of the anhydrite layer on the lightweight board use, in which the anhydrite serving as a defoamer is added tributyl phosphate will.

It has proven to be particularly advantageous according to a further embodiment of the invention to add anhydrite to 5 * tributyl phosphate to 100 percent by weight.

The invention is not restricted to this. The anhydrite layer a defoamer equivalent to tributyl phosphate can also be used for the lightweight construction panel or an addition of such a defoamer.

The defoamer is added in particular to the artificial, anhydrite obtained as residue.

Another embodiment of the invention provides an improvement and Cheaper the anhydride for lightweight panels by the fact that the anhydride a chemical additive serving as a liquefier or as a relaxation agent is added will.

Preferably, the liquefier is in the ratio of 1 to 3 percent by weight added to 100 96 anhydride. The liquefier has the composition that of the commercially available additives Anhyplan A or Anhydur Sb from BASF-AG. or under the trade name Melment known. By adding the condenser working hours can also be shortened.

It is also proposed that the same amount of fly ash be used instead of sand or artificial or natural stone-like fillers, powders or milled products to use.

Claims (5)

Claims lis Floor covering used as a screed in which by magnesite, cement or the like. wood wool bound and compressed as a binding agent, Wood chips or the like. is used as a plate body and the plate consists of several layers, preferably two layers (according to patent application P 24 21 170.9-25), thereby characterized in that the anhydrite layer of the lightweight panel contains tributyl phosphate, which serves as a defoamer. 2. Covering according to claim 1, characterized in that for the gnhydrite layer up to 5 weight percent tributyl phosphate per 100 weight percent anhydride is present is. 3. Covering according to claim 1 or 2, characterized in that the Anhydrite layer is made of synthetic anhydrite, which, in percent by weight, contains: calcium fluoride 1 - 2, calcium oxide 0.7 - 1.4, water 0.8 - 1.5, barium sulfate 0.1-0.8, iron and aluminum oxide 0.2-0.5, the remainder calcium sulfate. 4. Covering according to one of the preceding claims, characterized in that that the anhydrite layer with an individually known per se as a liquefying agent Serving chemical additive is set, preferably in a ratio of 1 to 3 percent by weight Liquefier to 100 percent by weight anhydrite. 5. Covering according to one of the preceding claims, characterized in that that the mixed component of the anhydrite layer is fly ash or an artificial, stone-like one Filler is.