PT105790B - METHOD OF COLORING NATURAL AND / OR ARTIFICIAL ORNAMENTAL AND AGGLOMERATED ROCKS - Google Patents

Abstract

The present invention relates to a method of coloring two-color natural and / or artificial ornamental and / or agglomerated natural or artificial clays in which colorants are used, such as potassium ferricyanide, ferric nitrate, nitric acid and a heat treatment for color fastening . THIS METHOD ALLOWS TO COLOR GRANITE OF CLEAR TONALITIES, CONFIRMING A HOMOGENEOUS COLORING, RESISTANT TO SOLAR RADIATION AND WASHING BY WATER.

Description

ORNAMENTAL AND AGGLOMERATED ROCK COLORING METHOD

NATURAL AND / OR ARTIFICIAL

TECHNICAL FIELD OF THE INVENTION

The present invention relates to the coloring of building materials, namely ornamental rocks and natural and / or artificial agglomerates.

BACKGROUND OF THE INVENTION

Granitic rocks are made up of two major groups of minerals, feldspars and quartz, which contain other minerals, such as mica and amphibole, to a lesser extent. The color of these rocks depends on the relative percentage between light and dark minerals and also on the presence and oxidation state of their main natural chromograph, iron.

Gray / bluish rocks, typical of unchanged rocks without natural impregnation with iron, are the most common and the least valued when compared to the rocks of more vivid tones.

For this reason, some granite staining methods referred to in patent applications are known from the prior art.

US4695487A, KR20020016606A so as to live. The methods set forth in the above patent application colors involve impregnating the rock or surface painting by a dye solution under normal pressure and temperature conditions or under vacuum and subsequently drying at ambient temperature or under ambient conditions. controlled.

The invention now described allows to color two-color granitic rocks simultaneously, giving them different aesthetic characteristics and very appealing. The method presented here can be applied to any rock, but is most effective on light-hued granitic rocks because some of the possible solvents are reactive with carbonated rocks.

SUMMARY OF THE INVENTION

The present invention relates to a method of coloring ornamental rocks and natural and / or artificial clusters comprising the following steps:

a) clean the pieces of stone to color;

b) dry the pieces;

c) preparing a potassium ferrocyanide dye solution;

d) heating the dye solution to a temperature of up to 70 ° C;

(e) submerge the stone referred to in (a) in the heated solution in (d);

f) remove the stone pieces from the solution;

g) wash the parts under running water for up to 5 seconds;

h) drying the pieces at a temperature of up to 70 ° C for a period of 0 to 24 hours;

(i) prepare a dye solution of ferrous nitrate and nitric acid;

j) heating the dye solution prepared in the previous step to a temperature of up to 70 ° C;

k) submerge the stone pieces referred to in h) in the coloring solution of the previous step;

l) remove the stone pieces from the coloring solution;

m) wash parts under running water to eliminate excess solution for up to 5 seconds;

(n) heat the parts to between 200 ° C and 300 ° C for 6 to 24 hours under aerobic conditions;

o) Remove parts from oven after cooling to room temperature.

In a preferred embodiment a water repellent is applied in the final phase.

In another preferred embodiment, the heating steps in points d) and j) take place in a water bath with temperature increments of 2 ° C / min.

In yet another preferred embodiment, the submersion steps in points e) and k) occur for a period of time from 6 to 48 hours.

In an even more preferred embodiment, the rock pieces referred to in step a) are dried in an artificial environment at temperatures below 70 ° C.

In another preferred embodiment, the dye solution used in step c) is comprised of from 70% to 90% by weight of water and from 10% to 30% by weight of potassium ferrocyanide.

In another preferred embodiment the dye solution used in step i) is comprised of from 65% to 85% by weight of water, from 15% to 35% by weight of ferrous nitrate and from 0% to 30% by weight of nitric acid.

Another object of the present invention are ornamental rocks and natural and / or artificial clusters which are colored by the method described above.

GENERAL DESCRIPTION OF THE INVENTION

The present invention relates to a method of coloring ornamental rocks and two-color agglomerates simultaneously, such as granite, which is based on the use of dye solutions to impregnate the rocks and subsequent heating to temperatures in the range of 200 to 200 ° C. 300 ° C for color fixation.

After being washed to remove impurities from the surface, the rock pieces are dried in a controlled environment at a temperature of up to 70 ° C, or at room temperature. After drying, the rock pieces are dipped in a solution containing water and potassium ferrocyanide. After this impregnation the parts are placed in another solution consisting of deionized water, nitric acid and ferrous nitrate. The concentration of the solutions used varies according to the dissolution capacity of the metallic elements and also according to the desired coloring intensity. Both impregnations can range from 6 to 24 hours depending on the porosity of the rock and the desired color intensity.

Once impregnated with both solutions, the rock pieces are placed in a heated environment at temperatures between 200 and 300 ° C for color fixation for 6 to 24 hours. After this step the parts cool to room temperature progressively with a cooling rate of 2 ° C / min.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a method of staining ornamental rocks and natural and / or artificial clusters to obtain rocks of two colors of different shades. The method is applied to pieces of rock with their final form.

The method is essentially based on submerging the coloring material into two dye solutions (solution 1 and solution 2) consisting of a dye and a solvent followed by a heating step for color fixation.

Said method for coloring these ornamental rocks and natural and / or artificial clusters is essentially characterized by the following generic operations:

(a) clean and / or dry the pieces of stone to be colored until all moisture is removed; If drying in an artificial environment is required, the temperature should not be

be greater than 70 ° C; O time drying should be the enough for to eliminate all the water present in the pores open and in the cracks of rock and will depend on thickness gives ask and gives temperature drying

used;

b) preparing the dye solution 1 in a container large enough to hold the pieces to be colored; conjugation of solute and solvent should allow complete dissolution without formation of residues;

c) heating the dye solution 1 to a temperature of up to

70 ° C; heating in a water bath should be carried out gradually in increments of 2 ° C / min;

d) submerging the stone pieces referred to in a) in the preheated dye solution 1 for a period of time ranging from 6 to 48 hours; Care should be taken to leave the faces to be colored in direct contact with the solution, i.e. without any overlapping or juxtaposed parts;

e) remove the stone pieces from the dye solution 1; during this operation the parts must be cleaned of any precipitates deposited on them;

f) wash the parts with running water to eliminate excess solution; This should be done quickly, with a duration of water contact of up to 5 seconds and if necessary the parts should be rubbed to remove any precipitates deposited on them.

(g) allow the parts to dry outdoors or at a temperature of up to 70 ° C for a period of time ranging from 0 to 24 hours; drying does not have to be complete and is intended to remove only the hygroscopic water film from the surface of parts;

h) preparing the dye solution 2 in a container large enough to hold the pieces to be colored; conjugation of solute and solvent should allow complete dissolution without formation of residues;

(i) heat dye solution 2 to a temperature of up to

70 ° C; heating in a water bath should be carried out gradually in increments of 2 ° C / min;

j) submerging the stone pieces referred to in a) in the preheated dye solution 2 for a period of time ranging from 6 to 48 hours; Care should be taken to leave the faces to be colored in direct contact with the solution, i.e. without any overlapping or juxtaposed parts;

k) remove the stone pieces from dye solution 2; during this operation the parts must be cleaned of any precipitates deposited on them;

l) wash parts under running water to eliminate excess solution; This should be done quickly, with a duration of water contact of up to 5 seconds and if necessary the parts should be rubbed to remove any precipitates deposited on them.

(m) place the parts in an oven and heat them between 200 ° C and 300 ° C for 6 to 24 hours under aerobic conditions; heating and cooling steps should be slow (2 ° C / min); the pieces must be placed so that all faces are free, without any overlapping or juxtaposed piece;

n) remove parts from the oven after they have reached room temperature;

o) apply a water repellent to the pieces, if the rock has high porosity.

Dye solution 1 and dye solution 2 have the following formulations.

Solution 1 formulation:

The composition and proportion are as follows: water (between 70% to 90% by weight) and potassium ferrocyanide (between 10% to 30% by weight).

Solution 2 formulation:

The composition and ratio are as follows: water (65 to 85 wt%), ferrous nitrate (15 to 35 wt%) and nitric acid (0 to 30 wt%).

APPLICATION EXAMPLE

As an example of application the following formulations were used for dye solutions 1 and 2:

• Dye solution 1: 1000 g of water and 150 g of potassium ferrocyanide.

• Dye solution 2: 1000 g of water and 400 g of ferrous nitrate.

The remaining conditions of this application example were as follows:

• Sample drying time before immersion in dye solution 1: 24 h at 60 ° C • Solution temperature: 20 ° C • Dipping time in dye solutions: 24 h in each dye solution • Drying conditions after dye solution 1 : 0.1 h at 20 ° C • Burning conditions after immersion in dye solution 2: 24 h at 250 ° C

The remaining test conditions and the precautions to be taken throughout the procedure were as mentioned above.

The following claims further represent preferred embodiments of the present invention.

Claims (5)

1 . Staining method for ornamental rocks and clusters natural and / or artificial characteristics comprising the following steps: The) clear the pieces of stone to color; B) dry the pieces; W) prepare a ferrocyanide dye solution of potassium; d) heating the dye solution to a temperature of up to 70 ° C; and) submerge the stone pieces referred to in a) in the heated solution in d); f) remove the stone pieces from the solution; g) wash parts under running water for up to 5 seconds; H) dry the pieces at a temperature of up to 70 ° C during the time from 0 to 24 hours; i) prepare a ferrous nitrate and acid dye solution nitric; j) heat the dye solution prepared in the previous step to a temperature of up to 70 ° C; k) submerging the stone pieces referred to in h in the dye solution of the previous step; D remove the stone pieces from the dye solution; m) wash parts under running water to remove excess solution for up to 5 seconds; n) heat the parts to a temperature between 200 ° C and 300 ° C for 6 to 24 hours under aerobic conditions; O) remove parts from oven after cooling to room temperature. 2. Method coloring in a deal with the claim previous, featured per apply in the final phase one water repellent on the parts. 3. Method coloring in a deal with Any of them of The preceding claims characterized in that the heating steps in (d) and (j) take place in a water bath at 2 ° C / min. Staining method according to any one of the preceding claims, characterized in that the submersion steps in (e) and (k) occur for a period of time from 6 to 48 hours. Staining method according to claim 1, characterized in that the drying of the rock pieces referred to in step a) is carried out under artificial conditions at temperatures below 70 ° C. Staining method according to claim 1, characterized in that the coloring solution used in step c) comprises from 70% to 90% by weight of water and from 10% to 30% by weight of potassium ferrocyanide. Staining method for ornamental rocks and natural and / or artificial agglomerates according to claim 1, characterized in that the coloring solution used in step i) comprises between 65% and 85% by weight of water, between 15% to 35% by weight of ferrous nitrate and between 0% to 30% by weight of nitric acid.