DE2540954B2 - PROCESS FOR THE PRODUCTION OF EASILY TOUCHABLE SOLID GYPSUM MIXTURES - Google Patents

Description

For the production of the granulate one goes from han-

The usual plaster of paris, largely of the formula

CaSO4 · V2 H2O. It is also possible to use ei-45 a part of this plaster up to about 50% by anhy-

It is known to replace dry mixes of plaster of paris and thirds. Preferred gypsum masses consist in

other auxiliaries, such as water-soluble cellulose percentages by weight, based on the sum of gypsum

fithern and fillers made in water and fillers

can be stirred in and as a spatula and 80.00 to 98.00 plaster,

Filling compounds for cracks in masonry u. The like. Suitable _050Ws 50 3 _{00 wa} s i _{Ser ös} union cellulose ethers,

are. Such dry _{messes tend to accumulate 2QQ bjs lg 00 fillersi)}

Practicing and baking often together so that they _{retard the binding when 0 01 to QSQ A}

Mixing can only be dosed poorly, _{as well as any} other auxiliaries.

It is known that by granulating dust-form

gen materials these into an easily applicable non-55 The water-soluble celluloseather are for dusting Convict form. These measures position of gypsum masses known per se. It will come for example, in the case of pharmaceuticals, fertilizers, methyl cellulose and / or metels are considered here and the like are often used. The here used ethylhydroxypropyl cellulose with a viscosity of 200 Liehe procedure is the compaction between to 5000 cP in 2% aqueous solution. After a see reels. This first creates flädienför- 60 expedient embodiment one uses nemige Scabs, which are then crushed into granules ben the aforementioned cellulose ethers up to 30% will. It was therefore also obvious, this measure- carboxymethyl cellulose.

took on powdered plaster of paris mixtures according to a further preferred embodiment wear. However, it has been found that although they are used as fillers for the dry midas Dusting is prevented and also a light layer of asbestos fibers, with a through dosage is possible, but on the other hand with the average fiber length of 0.05 to 0.2 mm. the Ren the gypsum mixture, which is made by adding to asbestos fibers in an amount of about 1 to Water happens, but agglomerations up to 8%, based on the dry mixture, are used.

Finally, one uses for the production of the invention Gypsum masses commercially available setting retarders such as tartaric acid, citric acid, condensed Phosphates or protein compounds of animal or vegetable origin. The above mentioned carboxymethyl cellulose also shows a retarding effect.

Of course, it is also possible to use the dry mixes for the production of gypsum-containing mixes Adding known auxiliaries to fillers and fillers, such as asbestos-like loosening agents, z. B. wood pulp, or kieselguhr, silica, magnesium carbonate or acceleration c the delay agent.

To produce the gypsum mixes according to the invention, the components are dry together mixed and granulated by means of a roller compacting system. The scabs are prepared in such a way that that all proportions below 0.1 mm and above 0.7 mm can be cut off. These can then be used again for granulation. As Already mentioned earlier, particularly favorable gypsum masses are obtained if the grain diameter is between 0.2 and 0.5 mm.

The application of the granulated plaster of paris is very easy. To make an approach about 100 parts by weight are poured into 50 to 70 parts by weight of water and stirred. Is the Mixture too pasty, can be diluted with water, while on the other hand it is possible to add more granules with low viscosity. Immediately after stirring the Mass smooth and workable. Depending on the composition, it hardens between about 20 minutes and 2 to 3 h.

example

95 kg of gypsum were mixed in a dry mixer with the following ingredients:

2.5 kg of asbestos fibers, fiber length less than 0.2 cm,
«00 g methyl cellulose, viscosity 200OcP

(in 2% solution according to Höppler),
200 g carboxymethyl cellulose (as sodium salt),

(Viscosity 25OcP in 2% solution according to Höppler),

500 g silica,
20 g of tartaric acid.

The mixture was then granulated on a dry granulating machine customary in Hanao (Wakenkompaktierung to form scabs with subsequent comminution) and all components above 0.5 rim and below 0.2 mm grain size separated.

ICO parts by weight of the mixture were in 60 wt [steep water was added and a homogeneous mixture was observed immediately after stirring. The compound was used to fill cracks in masonry and smooth uneven surfaces House walls used. It worked well with a spatula and trowel. The processing time was 1 h.

Claims (6)

step. In addition, in the presence of coarser patent claims: grains, it is practically not possible after the first entry for the purpose of thickening the mass. 1. Adding a process for the production of slightly different granules. This subsequently zugerührbaren, solid plaster mixes by granulation ₅ sat granules then breaks no longer completely. Darlieren, which should be used as a hardening spatula and filling compound, suffers from the uniformity and strength of the sen, thereby hardened gypsum mixture under certain circumstances completely indicates that one is essentially. It is already known for granulation to 80 tem gypsum existing gypsum mass by rolling _1O to 90 ° C heated raw gypsum a limited amount compact into a granulate with a grain of water to be sprayed on. One part of the size from 0.1 to 0.7 mm transferred. Hemihydrate converted into the dihydrate. This pre- 2. The method of claim 1, characterized overall gear must indicates that the plaster slurry in a granulate and therefore requires a high technimit a grain diameter of 0.2 to 0.5 mm ₁₅ with intensive mixing accurately controlled see control effort. It is true immediately after being brought over. setting of the gypsum granulate, the setting time can only be 3. The method according to claim 1 and 2, characterized in that the amount present is characterized by the fact that the gypsum masses to the following of dihydrate serves as an accelerator for the further composition in percent by weight, based on hardening, the granulate is against Feuchligauf the sum of gypsum and fillers, in a _ao ness very sensitive and tends to be transferred to lumps or granules: for hardening. Furthermore, it was known by snnnw osnn r- precipitation obtained particularly fine-grained gypsum me- 80.00 to 98.00 gypsum, dianisA to be compacted to such an extent that it ? 'nnS ^S ie nS *. ^{a, s, SERL} _f ^o _f ^sllche Celluloseather, _{yon properties of natuer lidl} degraded material overall rt'm E- n «n Auu ^StO i ··» 5 received stucco plaster. 0.01 to 0.50 setting retarder « _{task of the preliminary} {; _{It was the most important invention} , such and, if necessary, other auxiliaries. create dust-free, easy-to-dose plaster mixes 4. The method according to claim 3, characterized in that, on the one hand, it easily indicates without agglomeration, that as water-soluble cellulose are stirrable and that allow it to be mixed with additional ether a methyl cellulose and / or methyl 30 would add the gypsum mixture to the water-containing paste hydroxypropyl cilulose with a viscosity of 200 to produce a desired consistency. up to 5000 cP in 2% solution is used. The inventive method for production 5. The method according to claim 3, characterized by easy-to-mix, solid gypsum masses indicates that as water-soluble cellulose granulating, the ais hardening spatula and filling ether In addition to methyl cellulose and methylhydroxyl compounds, this means that propyl cellulose is used 30% carboxymethyl cellulose distinguishes that one is essentially used with water will. this hardenable plaster of paris existing plaster of paris 6. The method according to claim 3, characterized by roller .icompacting into a granulate with a indicates that asbestos fibers have a grain size of 0.1 to 0.7 mm as filler. Preferential will. 40 wise, the plaster of paris should be converted into granules with a grain diameter of 0.2 to 0.5 mm.