RU2084420C1 - Method of manufacturing facing and ornamental parts from artificial stone - Google Patents

Abstract

FIELD: manufacture of building materials. SUBSTANCE: molding blend composed of magnesia cement, magnesium chloride, sand, dyeing pigment, and water is supplemented with plasticizer, alumina- chromium-phosphate additive, and ground quartz sand. Magnesium chloride solution with density 1.2-1.25 g/cu. cm is first prepared and then mixed with plasticizer, alumina-chromium-phosphate, and cement paste. Resultant mix is stirred in concrete mixer with dry mixture caustic magnesite, sand, and ground sand to yield sand blend which is put into molds and hardened. EFFECT: improved ornamental and physico-mechanical properties.

Description

 The invention relates to the building materials industry based on magnesian binder and can be used in the production of material for external and internal wall cladding, elements of buildings and structures, or for flooring inside residential, public and domestic premises, as well as for stoves, fireplaces and other decorative goals.

A known method of manufacturing molded finishing products having a cloud-like pattern, comprising mixing 15-45 parts by weight white cement or Portland cement with 15-45 parts by weight more than one inorganic material such as limestone, marble, dolomite, calcite, quartz sand, having a white or gray color and 10-70 parts by weight inorganic materials of white or gray color with a particle diameter of 1-7 mm. 15-40 g of water are added to such a mixture per 100 g of cement and fine-grained and coarse-grained materials and mixed. The resulting mixture is divided into groups, to which, in addition to the white group, the required amount of pigment of the desired shade or a mixture of pigments is added and each group is thoroughly mixed. Then the mixture is prepared from the above groups without fully mixing, then the mixture is placed in the mold and subjected to vibration, cured and separated from the mold [1]
There is also a known method of manufacturing a facing or based on mixtures containing caustic magnesite, mineral aggregate, a mixture of quartz and basalt sand and gravel fractions of 0.10-10 mm or marble-granite gravel and sand mixture of fractions of 0.14-2.5 mm, an aqueous solution magnesium chloride, a pigment and a plasticizer, which is used as a drying oil, which includes mixing dry caustic magnesite and mineral aggregate in a mixer, then without stopping mixing, an aqueous solution of chlorine is sequentially introduced into the mixer magnesium and carbamide, plasticizer and pigment [2]
Products obtained by these methods have insufficiently high strength and a vague fuzzy pattern resembling weathered rocks.

 Closest to the invention is a method of manufacturing artificial finishing products, according to which it involves the preparation of at least two mixtures, with different dyes, each of which contains magnesia cement, magnesium chloride, sand, dye and water, laying the mixtures in smooth forms bottom and curing, with the dry components, magnesia cement, quartz sand, dye initially mixed until complete mass uniformity and then an aqueous bischofite solution is added and mixed again, after entrapment of a mixture with different dyes is discretely placed in a mixing container, partially mixed until a given pattern is obtained on the surface, each mixture containing the indicated components in wt.

magnesia cement 30-60
magnesium chloride 20-40
silica sand 1-24
dye 3-15
water the rest
In addition, laying in the molds of the resulting mixture is made by drawing to the bottom with the translational movement of the mixing tank relative to the mold in an inclined position (US Pat. 1738087, class B 28 B 11/00, 1992).

 The introduction of a hardening accelerator, in this invention, bischofite into colored mixtures of magnesium chloride, allows to obtain higher decorative qualities of products by reducing the spreading of dyes and, as a result, obtaining a clear pattern.

 However, the high content of bischofite in the mixture is not only economically unprofitable, but leads to increased requirements for the speed of laying in the mold and cracking of the mixture in the molds.

 The objective of the invention is the creation of a technologically advanced, economical and environmentally friendly method for the manufacture of facing and decorative products from artificial stone, which has good physical, mechanical and decorative properties.

 The essence of the claimed technical solution lies in the fact that in the method of manufacturing facing and decorative products from artificial stone, comprising preparing a molding mixture containing magnesia cement, magnesium chloride, sand, coloring pigment and water, laying the mixture into molds and curing, according to the invention, the molding mixture is introduced plasticizer C-3, alumochromophosphate additive and ground quartz sand fraction minus 20 microns in the following ratio of components wt.

caustic magnesite powder 25-40
magnesium chloride (bischofite) 10-20
sand, fractions (-1 mm) 30-50
ground silica sand (-20 microns) 6-10
aluminum chromophosphate 0.3-0.6
plasticizer C-3 0.1-0.2
pigment coloring 2-4
water the rest.

Moreover, a solution of magnesium chloride with a density of 1.2-1.25 g / cm ^{3 is} preliminarily prepared, mixed with a plasticizer, aluminum chromophosphate and pigment paste, and then the prepared solution is mixed in a concrete mixer with a dry mixture of caustic magnesite, sand and ground sand, obtained by molding the mixture is laid in molds, the mixture is compacted by vibration and cured by aging in normal climatic conditions.

 The introduction into the molding mixture of fine quartz sand, C-3 plasticizer and aluminochromophosphate in a solution of magnesium chloride in the indicated amounts allows achieving physical and mechanical properties of a material similar to marble.

 The introduction of the pigment in the molding mixture, which consists in first transferring the pigment to an aqueous paste, then it to a solution of magnesium chloride with a plasticizer aluminum chromophosphate, then mixing this solution with a dry mass, allows you to get the surface of products with high decorative properties at a lower consumption of expensive pigment.

 The method does not require the use of expensive equipment, does not require large energy costs, is technologically simple and environmentally friendly.

 The method is as follows.

First, an aqueous solution of magnesium chloride with a density of 1.22 g / cm ³ is prepared, C-3 additives and aluminum chromophosphate are added to the solution in the indicated amounts. Part of the solution is left colorless. A pigment paste prepared as follows is introduced into another part of the solution with additives: a pigment pre-soaked with water (paste moisture 30-40%) is passed through a paint grater; The resulting pigment paste can be stored in a sealed, sealed container.

 The preparation of the molding mixture is carried out in batch mixers. A solution of magnesium chloride with colorless additives, sand, ground sand and magnesite is fed into one mixer. Mix thoroughly. In another mixer serves a solution of magnesium chloride with pigment and all components of the dry mass, mix thoroughly. They randomly mix 20% of the color mixture with colorless in the intermediate tank and place the mixture in plastic molds mounted on a vibrating table, where the mixture is compacted for 10-15 seconds.

 Forms with mass are moved to horizontally installed racks and left to harden for 1 day under normal climatic conditions. Then they take out, the products from the mold and stack on racks for final ripening and a set of tempering strength for 15 days.

 An example of manufacturing a marble slab measuring 500x250x15 mm.

For the manufacture of 1 m ² plate requires 25 kg molding sand, of which 5 kg are colored. Prepares 7.5 liters of a solution of magnesium chloride, for which: weigh 5 kg of magnesium chloride, bring the volume of the solution with warm water to 7.5 liters by stirring. After dissolving and cooling the solution, measure the density and bring the density to 1.22 g / cm ^{3 by} gradual dilution. The resulting solution is filtered. To the filtered solution we add 112 ml of alumochromophosphate and 37 ml of platifier C-3. Mix thoroughly, pour 1.5 liters from the resulting solution to prepare a color solution. To prepare a pigment paste, we take 70 g of natural shungite and grind with the required amount of water until a thick sour cream is obtained. The resulting paste is added to 1.5 l of a solution of magnesium chloride with additives and mix thoroughly.

 Weigh 10 kg of magnesite, 2.5 kg of ground sand and 12.5 sand (-1 mm), mix thoroughly 20 kg of dry weight by mixing with a colorless solution of magnesium chloride, and 5 kg with color.

 With a few movements we mix the colorless and colored mass and spread it with the drawing down into the plastic molds mounted on the vibrating table. We vibrate for 10-15 seconds, then we place the forms with the mass on horizontally installed racks for a day. Next, remove the plate from the mold and leave for final ripening for 14 days.

After a set of tempering strength, the slab has a marble-like shiny surface and the following physical and mechanical parameters:
compressive strength, not less than (MPa) 50
bending strength, not less than (MPa) 15
water absorption, no more (%) 5,0
frost resistance, not less than (cycles) 50
abrasion, not more (g / cm ² ) 0.7 s

Claims (1)

 A method of manufacturing a facing and decorative products from artificial stone, including the preparation of 2 different color mixtures containing caustic magnesite powder, an aqueous solution of magnesium chloride, pigment and water, their incomplete mixing, laying the resulting molding sand mixture in a mold and curing under normal conditions, characterized the fact that mixtures of different colors are prepared by pre-mixing an aqueous solution of magnesium chloride with an aluminum chromophosphate binder and superplasticizer C-3 based on sodium salts product and condensation of naphthalenesulfonic acid and formaldehyde, separation of the resulting solution for 2 hours, followed by the introduction of pigment mixed with water into one of them and caustic magnesite, finely divided sand fraction less than 1 mm and finely ground sand fraction less than 20 microns and after laying in the form carry out vibration, while the ratio of the components of the molding mixture is, wt. Caustic Magnesite Powder 25 40
An aqueous solution of magnesium chloride 10 20
Pigment 2 4
Alumochromophosphate bond 0.3 0.6
Specified superplasticizer 0.1 0.2
Fine-grained sand fractions less than 1 mm 30 50
Fine sand fractions of less than 20 microns 6 10
Water Rest