JPH0769691A - Material for coloring cement and production thereof - Google Patents

Abstract

PURPOSE:To provide the material for coloring cement which is made easy in handling and is improved in dispersibility into a cement mixture and the fluidily and color developability of cement paste and the process for production by which the material for coloring cement is industrially obtd. CONSTITUTION:This material for coloring cement consisting of granules having 300 to 1500mum average particle diameters and having the porosity obtd. by the equation within a 0.1 to 0.3 range is obtd. by adding and mixing a surfactant to and with magnetic iron oxide pigment powder at 0.01 to 10wt.% by the weight of the magnetic iron oxide pigment powder to prepare powder to be treated, then subjecting the powder to be treated to a compression deaeration treatment under conditions under which a line pressure of a 10 to 100000g/cm range is applied to the entire powder to be treated housed in the state of restraining the powder in a specified space.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cement coloring material used for a structure made of color concrete or color mortar, which facilitates its handling and
Disclosed is a cement coloring material having improved dispersibility in a cement mixture, improved fluidity of cement paste, ease of construction, and color development, and a method for producing the same.

[0002]

2. Description of the Related Art In recent years, as environmental problems have been widely taken up, the appearance and color tone in consideration of the natural environment are also required for artificial structures made of concrete or mortar.

Correspondingly, a white or gray single color in a concrete or mortar structure is so artificial and highly saturated that it does not match the surrounding landscape.
There is a demand for a structure made of color concrete or color mortar which is colored with a black or brown pigment to reduce the saturation.

Conventionally, a structure made of color concrete or color mortar has a cement coloring material (coloring pigment powder) usually added to a cement mixture containing various additives such as crushed stone, sand, water, cement, and AE water reducing agent. It is constructed and constructed using color cement manufactured by mixing less than 5% by weight. It is mainly used on the slopes of buildings, promenades in parks, roads, etc. or the sea or river for the purpose of compatibility with the natural environment and aesthetic purposes. It has been widely applied to various structures such as seawalls.

Generally, as a method for producing color cement, a cement coloring material is directly put in a mixer containing a cement mixture obtained by previously kneading crushed stone, sand, water, an AE water reducing agent and cement as described above. And knead,
The method of coloring the cement mixture is adopted.

The cement coloring material used in the above manufacturing method is in the form of fine particles in consideration of dispersibility in the cement mixture, and therefore, the kraft paper bag containing the cement coloring material is used. When the bag is unpacked or put into a mixer, the pigment is severely scattered, which significantly deteriorates the working environment. Further, the cement coloring material itself has poor fluidity and is highly adherent, and these inconveniences of handling cause many troubles in the mechanization (automation) of the charging process.

Moreover, when the cement coloring material is put into the mixer at one time, the cement coloring material becomes agglomerate or floats on the surface of the cement mixing material, so that the dispersibility in the cement mixing material and the coloring property. However, there is a problem in that the kneading time becomes worse and the kneading time is inevitably lengthened.

In addition, when the cement coloring material is charged into the mixer in the above manufacturing method, it is usually 5
A so-called batch system is employed in which a kraft paper bag containing 25 kg to 25 kg is unpacked and manually loaded.

As a prior art for solving the problems of dispersibility of cement coloring material in cement mixture, prevention of scattering, etc., there is a cement coloring material in the form of granules obtained by spray drying a slurry containing a pigment. Known (Table 1
In the present situation, the results of JP-A-500586 and JP-A No. 2-307847 are not sufficiently satisfactory as a material for cement coloring.

Recently, there has been proposed a package in which a cement coloring material as a cement admixture is packaged in an alkali-soluble sheet and can be added to the cement mixture as it is (JP-A-5-9900). Although it is possible to prevent pigment scattering at the time of inputting the material, it is clear that the dispersion in the cement mixing material becomes worse as in the case where the material for cement coloring is added at one time, and the kneading time becomes long, No measures have been taken to improve dispersibility.

On the other hand, the color obtained by cement coloring depends on the type of the colored pigment powder used. Colored pigment powders include inorganic and organic types, but inorganic types are mainly used.For example, white is titanium white, red is hematite, yellow is goethite, and black is magnetite or carbon. Maghemite is used for black and brown.

[0012]

In producing a color cement, cement coloring materials are crushed stone, sand, water,
Special care must be taken in the handling of cement and AE water reducing agents. In addition, in order to obtain black or dark brown,
There are various pigment powders used to increase blackness by mixing with other colors, but for example, carbon black has a safety problem such as carcinogenicity and is hydrophobic. Therefore, it cannot be said that it is suitable for dispersion in a cement mixture which is a water dispersion system. Furthermore, “When carbon black is mixed at 5% or less, the strength is reduced by 30% or more.” “Cement Colorant Kazuo Omata” Pigment No. 1
Volume 6 p1292 Lower left 11th to 12th lines (1972) As described in the description, the problem of strength reduction of cement when carbon black is used is pointed out, and carbon black is suitable as a black pigment for cement coloring. I can't say. After all, magnetite and maghemite are suitable as the black and brown pigment powder for cement coloring in view of safety and economy. However, when using magnetic iron oxide pigment powder such as magnetite or maghemite,
It is known that magnetic agglomeration is likely to occur and dispersibility deteriorates because it has magnetic properties different from conventional non-magnetic inorganic coloring pigment powders, and it requires a long time of kneading. Has been used under conditions. Therefore, the cement coloring material using these magnetic iron oxide pigment powders is easy to handle, and the cement coloring material has improved dispersibility in the cement mixture and fluidity and color development of the cement paste. It is said to be the biggest technical issue in the color cement industry.

[0013]

The present inventors have found that among the cement coloring materials (coloring pigment powders) used for producing color cement, magnetite, maghemite, etc., which are used particularly for obtaining black or dark brown color. The cement coloring material using the above magnetic iron oxide pigment powder is easy to handle and has excellent dispersibility in the cement mixture, and the fluidity of the cement paste, ease of construction and color development As a result of various studies to solve the above-mentioned technical problems by making it excellent, the magnetic iron oxide pigment powder is 0.01 to 10 with respect to the magnetic iron oxide pigment powder.
A powder to be treated was prepared by adding and mixing wt% of a surfactant, and the powder to be treated was granulated by compression deaeration to have an average particle diameter of 300 to 1500 μm, and the porosity determined by Equation 1 was 0. The inventors have found that a cement coloring material composed of a granulated product within the range of 1 to 0.3 is suitable as a coloring material for color cement, and have completed the present invention.

That is, the present invention relates to a magnetic iron oxide pigment powder and 0.01 to 10% by weight based on the weight of the magnetic iron oxide pigment powder.
The average particle size obtained by granulating the mixture with the surface active agent by compression degassing is in the range of 300 to 1500 μm, and the porosity determined by the equation 1 is in the range of 0.1 to 0.3. A cement coloring material consisting of a certain granulated material, and a powder to be treated by adding 0.01 to 10% by weight of a surfactant to the magnetic iron oxide pigment powder and mixing it with the magnetic iron oxide pigment powder. 10 to 10 of all the powders to be treated stored in a fixed space in a bound state.
The method for producing a cement coloring material is characterized in that granulation is carried out by compression deaeration under the condition that a linear pressure in the range of 0000 g / cm is applied.

[0015]

[Equation 1]

Next, various conditions for carrying out the present invention will be described. The cement coloring material according to the present invention is obtained by granulating a mixture of a magnetic iron oxide pigment powder and a surfactant of 0.01 to 10% by weight based on the weight of the magnetic iron oxide pigment powder by compression deaeration treatment. The average particle size is 300-1500μ
It is comprised of a granulated material having a porosity in the range of m and a porosity of 0.1 to 0.3.

The magnetic iron oxide pigment powder used in the present invention is magnetite ( FeO x .Fe ₂ O) which is a black pigment powder.
₃ (0 <x ≦ 1)), magnetic iron oxide pigment powder such as maghemite (γ-Fe ₂ O ₃ ) which is a brown pigment powder can be used.

The particle shape of the magnetic iron oxide pigment is granular, spherical,
Cubic, octahedral, needle-shaped, spindle-shaped, etc., all of which are obtained by a conventional method can be used. The shape is preferably octahedral or spherical. Further, those having a particle size of 0.05 to 20 μm can be used. It is preferably used in the range of 0.1 to 10 μm.

As the surfactant, a cationic, anionic, nonionic or amphoteric surfactant can be used.
For example, as the cationic surfactant, an alkylamine salt type or a quaternary ammonium salt type can be used.
Examples of the anionic surfactant include an alkyl sulfate ester type, an alkylbenzene sulfonate type, a naphthalene sulfonate formalin condensate type, an aromatic sulfonate formalin condensate, and a carboxylic acid type polymer surfactant. Examples of the nonionic surfactant include polyoxyethylene alkyl ether and polyoxyethylene alkylphenyl ether. Examples of the amphoteric surfactant include lauryl betaine type and lauryl dimethylamine oxide type. An anionic surfactant is preferably used.

The amount of the surfactant added is 0.01 to 10% by weight based on the magnetic iron oxide pigment powder.
When it is less than 0.01% by weight, it becomes difficult to granulate a granulated product having an appropriate strength, and the obtained granulated product becomes fragile, and the scattering property of the cement coloring material cannot be prevented. . On the other hand, when the content exceeds 10% by weight, the fluidity of the cement paste apparently increases, but actually the dispersion in the cement admixture is rather insufficient and the original color of the pigment cannot be obtained. In the case of powder, the lightness index L ^{* of the} colorimetric index defined in JIS Z8729 is high in the colorimetric result, and sufficient blackness cannot be obtained.

When the average particle diameter is less than 300 μm, the problem of scattering of the cement coloring material occurs, which deteriorates the working environment. When it exceeds 1500 μm, it takes time to disperse the cement coloring material in the cement mixture, which is not economically preferable.

When the porosity determined by the equation 1 is less than 0.1, although the micro air contained in the aggregate of the magnetic iron oxide pigment powder is sufficiently degassed, magnetic aggregation occurs. The resulting granules have high strength and can prevent scattering, but it is not preferable because it takes a long time to uniformly disperse them in the cement mixture and the color develops poorly. On the other hand, when the porosity calculated by the equation 1 exceeds 0.3, the micro air contained in the aggregate of the magnetic iron oxide pigment powder is not sufficiently deaerated, so that the present invention Can not exert the effect of.

The cement coloring material according to the present invention is a powder to be treated by adding 0.01 to 10% by weight of a surfactant to the magnetic iron oxide pigment powder and mixing it with the magnetic iron oxide pigment powder. This powder to be treated is used as a body and 10 to 10 to all the powder to be treated stored in a state of being bound in a fixed space.
Under the condition that the linear pressure in the range of 0000 g / cm is applied,
It can be obtained by granulation by compression degassing.

The compression deaeration process according to the present invention must be carried out under the condition that a compressive force is applied to all the powders to be treated contained in a fixed space in a state where the powders to be treated are bound. The bound state is a state in which the powder to be processed is restrained from freely moving and escaping from the stress field with respect to the compressive force applied thereto, and a forced compressive force is applied to the powder layer. Therefore, the effect of the present invention cannot be exhibited by the compression degassing treatment in an unconstrained state.

A sand mill, a pressure press, a roll press, a gear continuous compressor, or the like can be used as the compression deaerating apparatus that can satisfy the above conditions. Furthermore,
Simpson mills, edge runners, smelting machines and the like can also be used as the compression deaerating apparatus in the present invention by appropriately selecting the amount of powder to be treated, the layer thickness of the powder layer at the time of treatment and the like. It is preferable to use a roll press.

In carrying out the compression degassing treatment in the present invention, the linear pressure for compression is 10 to 100,000 g / c.
The range is m. Within this range, it can be appropriately selected and set according to the type of powder to be treated, the specific surface area, the type of compression degassing apparatus, and the like. Preferably 100-5
It is in the range of 0000 g / cm.

When the linear pressure is less than 10 g / cm, the effect of the present invention cannot be obtained because it does not contribute to the improvement of dispersibility due to microscopic deaeration. When the linear pressure exceeds 100,000 g / cm, deaeration of the micro air contained in the aggregate of magnetic iron oxide pigment powder is sufficient, but on the other hand, strong magnetic agglomeration occurs and the cement mixture Unfavorably because the dispersibility in the

The granules obtained by compression degassing are 2
Although it may form flakes in the form of flakes that are slightly larger in appearance as a secondary structure, the fluidity is improved by appropriately crushing and sizing to obtain a granulated product having an arbitrary average particle size according to the application, It is possible to obtain a cement coloring material which is excellent in adhesiveness and dust generation and is easy to handle.

By packaging the cement coloring material according to the present invention obtained by compression deaeration with alkali-soluble paper, the cement coloring material can be directly added to the cement mixture, and is easy to handle without pigment scattering. In addition, a cement coloring package having improved dispersibility can be obtained. As the alkali-soluble paper, known ones such as those made of carboxymethyl cellulose (CMC) or carboxyethyl cellulose (CEC) fibers which are insoluble or sparingly soluble in water can be used.

When using the cement coloring material according to the present invention, when it is necessary to adjust the color,
Nonmagnetic iron oxides such as goethite which is a yellow pigment powder and hematite which is a red pigment powder, and titanium white which is a white pigment powder may be mixed in appropriate amounts.

When the cement coloring material according to the present invention is added to the cement mixture, the cement coloring material is previously made into a high-concentration water suspension,
It can be added to the cement admixture.

[0032]

First, the most important point in the present invention is that the magnetic iron oxide pigment powder has a weight ratio of 0.
A powder to be treated was prepared by adding and mixing 01 to 10% by weight of a surfactant, and the powder to be treated was granulated by compression deaeration, and the average particle size was in the range of 300 to 1500 μm. By using a cement coloring material composed of granules having a required porosity within the range of 0.1 to 0.3, dispersibility in cement mixture, fluidity of cement paste, ease of construction, and color development It is a fact that a cement mixture having excellent properties and easy to handle can be obtained without causing troubles such as scattering of color pigment powder.

In the present invention, the reason why the cement coloring material having the above-mentioned various properties can be obtained is not yet clear, but the present inventor thinks as follows. The compression deaeration process deaerates the microscopic air contained in the aggregate of magnetic iron oxide pigment powder, and the interparticle distance becomes smaller, which causes magnetic interaction to cause partial magnetic aggregation. . That is, as the compression deaeration process is strengthened, microscopic deaeration that has a good effect on the wettability with water and the dispersibility progresses, while magnetic coagulation, which has a bad effect on the dispersibility, also occurs one after another. become. Therefore, it can be said that the compression deaeration treatment should be performed under the condition that the effect of improving the dispersibility is much larger than that of the magnetic agglomeration that adversely affects the dispersibility. In fact, according to the experimental results of the present inventor, the range of the linear pressure at which the optimum dispersibility is obtained is 10 to 100,000 g / cm, and as described above, the dispersibility deteriorates when the linear pressure exceeds 100,000 g / cm.

When the cement coloring material obtained by compressing and degassing with a linear pressure within the above-mentioned optimum range is put into a mixing mixer, the shearing force due to the interaction with crushed stone, sand, cement, etc. and the stirring The cement coloring material is easily disentangled, and the water is replaced with air without magnetic agglomeration, so that the pigment powder is sufficiently wetted with water, dispersibility in the cement mixture and fluidity of the cement paste.・ A cement coloring material with excellent workability and color development and easy to handle can be obtained.

[0035]

EXAMPLES The present invention will be described with reference to Examples and Comparative Examples. In the following Examples and Comparative Examples, the value of "particle density" required for calculating the porosity obtained by the equation 1 was obtained by the equation 2 using a pycnometer by the liquid immersion method.

[0036]

[Equation 2]

The bulk density is obtained as follows. The inner volume of the bottom placed on a horizontal surface is 5.0 cm, and the internal capacity is 5
The funnel is set on a 00 ml cylindrical measuring cup, and the sample powder is gently dropped from the funnel into the measuring cup. When the sample powder is piled up in the fixed quantity cup, stop the sample powder from falling and scrape it with a spatula so that it is completely filled. The weight of the sample powder in the measuring cup, which is just 500 ml, is weighed with a balance, and the bulk density is calculated by Equation 3.

[0038]

[Equation 3]

The mortar flow value, which is an index of cement fluidity, is obtained as follows. As specified in JIS R 5201, white cement 520g, Toyoura standard sand 10
15.6 g of pigment powder and 338 ml of water were added to 40 g,
After kneading at low speed for 3 minutes with a mortar mixer, the mortar is packed in a flow cone placed in the center of the flow table.
After packing, the cone was taken out and immediately subjected to vertical vibrations 15 times for 15 seconds, the spread of the mortar and the diameter in the direction perpendicular to the maximum diameter were measured in mm, and the average value is represented by an unnamed number. The measurement was performed twice with the same mortar, and the average value of the two times was taken as the mortar flow value.

The color developability is evaluated as follows. The remaining paste after mortar flow measurement was fixed on a smooth glass plate and the size of the piece was 4 cm.
It was poured into an acrylic mold frame of 10 × 4 cm × 0.5 cm, molded with a sufficient stick, and left in a room at 20 ° C. for 1 day. The next day, the test piece removed from the mold was cured in water at 20 ° C. for 1 day. A smooth surface measurement of the dried test piece after curing is measured with a color difference meter (manufactured by Suga Test Instruments Co., Ltd.), and the color of the cement test piece colored with pigment powder is defined by JIS Z8729. Indexes L ^* , a ^* , b ^* , and c ^* =
The saturation index c ^* defined by (a ^* × a ^* + b ^* × b ^* ) ^1/2 was measured and evaluated.

Example 1 First, 500 g of regular octahedral magnetite (average particle size 0.30 μm, porosity 0.520, bulk density 0.49 g / ml) as magnetic iron oxide pigment powder was suspended in 5 l of water, and the water temperature was adjusted. To the suspension at 50 ° C., 5 g of a sodium salt of an aromatic sulfonic acid formalin condensate (trade name: Demol SC Kao Co., Ltd.) was added as an anionic surfactant, and the mixture was stirred for 10 minutes. It was Then, the suspension was filtered, washed with water and dried by a conventional method to obtain a black pigment powder treated with an anionic surfactant. Next, the black pigment powder was charged in a sand mill and the linear pressure was 5 g at a linear pressure of 10 g / cm.
A compression deaeration process was performed for a minute. The black pigment powder that had been subjected to the compression deaeration treatment was in the form of flakes and had a thickness of 1.20 mm. Subsequently, the compressed and degassed black pigment powder is crushed and classified by a conventional method to form a granulated product having an average particle size of 630 μm, a porosity of 0.126 and a bulk density of 0.84 g / ml. A black pigment powder for coloring cement was obtained. The obtained black pigment powder for cement coloring was easy to handle without causing scattering. The mortar flow value of the obtained black pigment powder for cement coloring was 250, and L ^* was 53.5, a as a colorimetric measurement result of the cement test piece with a color difference meter.
^* Was -0.47, b ^* was -2.72, and c ^* was 2.76. The results of these measurements are shown in Table 1.

In Example 1, as compared with Comparative Examples 1 and 2 described later, the lightness index L ^* is lower, so that the blackness is higher, and since the saturation index c ^* is lower, the degree of achromatic color is higher. Admitted. Further, in Example 1, it was confirmed that the mortar flow value representing the fluidity of the cement paste was large and the dispersibility of the pigment powder in the cement mixture was improved as compared with Comparative Example 1 described later.

Example 2 As a surfactant, 12.5 g of a naphthalene sulfonate formalin condensate system (trade name: Demol N Kao Co., Ltd.), which is an anionic surfactant, was used, and compression degassing treatment was performed. A cement made of a granulated product having an average particle size of 630 μm, a porosity of 0.112 and a bulk density of 0.88 g / ml in the same manner as in Example 1 except that the press was performed at a linear pressure of 5000 g / cm. A black pigment powder for coloring was obtained. Table 1 shows the mortar flow value of the obtained pigment powder for cement coloring, and the color measurement result of the cement test piece by the color difference meter.

Example 3 Spherical magnetite (average particle size 0.35 μm, porosity 0.58, bulk density 0.52 g / as magnetic iron oxide pigment powder)
ml), 7.5 g of a carboxylic acid type polymer system (trade name: Poise 521, manufactured by Kao Corporation), which is an anionic surfactant as a surfactant, and compression deaeration treatment is performed using a roll press. Black pigment powder for cement coloring consisting of granules having an average particle size of 640 μm, a porosity of 0.102 and a bulk density of 0.92 g / ml, in the same manner as in Example 1 except that the linear pressure was 45,000 g / cm. Got the body Table 1 shows the mortar flow value of the obtained pigment powder for cement coloring, and the color measurement result of the cement test piece by the color difference meter.

Example 4 The same spherical magnetite as in Example 3 was used as the magnetic iron oxide pigment powder, and a quaternary ammonium salt system (trade name: Kotacin 24P, which is a cationic surfactant as a surfactant).
Example 1 except that 10 g of Kao Co., Ltd.) was used and the compression degassing treatment was performed using a sand mill at a linear pressure of 10 g / cm.
Similarly, the average particle size is 530 μm and the porosity is 0.24.
7. A black pigment powder for cement coloring was obtained, which was a granulated product having a bulk density of 0.76 g / ml. Table 1 shows the mortar flow value of the obtained pigment powder for cement coloring, and the color measurement result of the cement test piece by the color difference meter.

Example 5 As magnetic iron oxide pigment powder, 500 g of needle-shaped maghemite (average major axis diameter 0.30 μm, axial ratio 12, porosity 0.76, bulk density 0.35) was suspended in 5 liters of water, and the water temperature was suspended. 50 ℃
7.5 g of polyoxyethylene alkylphenyl ether type (brand name: Emulgen 911), which is a nonionic surfactant, was added to the suspension prepared as
Stir for 0 minutes. Subsequently, the suspension was filtered, washed with water, and dried by a conventional method to obtain a brown pigment powder treated with a nonionic surfactant. Next, the brown pigment powder was subjected to compression deaeration treatment by a roll press at a linear pressure of 100 g / cm for 5 minutes. The compression-deaeration-treated brown pigment powder is flaky, so it is crushed and classified by a conventional method, and is composed of granules having an average particle diameter of 450 μm, a porosity of 0.231 and a bulk density of 0.77 g / ml. A brown pigment powder for coloring cement was obtained. The obtained brown pigment powder for coloring cement was easy to handle without causing scattering. Table 1 shows the mortar flow value of the obtained pigment powder for cement coloring, and the color measurement result of the cement test piece by the color difference meter.

In Example 5, the lightness index L ^* was lower than in Comparative Example 5 described later, the color was closer to the brown color originally shown by maghemite, and the mortar flow value representing the fluidity of the cement paste was large and the cement of pigment powder was used. It was confirmed that the dispersibility in the mixed material was improved.

Example 6 In the same manner as in Example 5 except that 7.5 g of Demol SC was used as a surfactant, an average particle diameter of 420 μm, a porosity of 0.211, and a bulk density of 0.77 g / ml were prepared. A dark brown pigment powder for coloring cement which was composed of granules was obtained. Table 1 shows the mortar flow value of the obtained pigment powder for cement coloring, and the color measurement result of the cement test piece by the color difference meter.

Comparative Example 1 Instead of the cement coloring material composed of the granulated product of Example 1, regular octahedral magnetite (average particle size 0.30 μm, porosity 0.520, bulk density 0.49 g / ml) was used as it was. A black pigment powder for coloring cement was used. Table 1 shows the mortar flow value of the black pigment powder for coloring cement and the color measurement result of the cement test piece by the color difference meter. In addition, since the color pigment was used in a powder state during the production of the color cement, the color pigment was scattered and it was difficult to handle.

Comparative Example 2 In Example 1, the linear pressure of the compression degassing treatment was 100,000.
A black pigment powder for cement coloring consisting of granules having an average particle size of 650 μm, a porosity of 0.089 and a bulk density of 1.02 g / ml, except that the same operation was performed except that the operation was performed at 0 g / cm. Got the body Table 1 shows the mortar flow value of the obtained pigment powder for cement coloring, and the color measurement result of the cement test piece by the color difference meter.

In Comparative Example 2, since the compression deaeration treatment was performed by applying a very large linear pressure, the mortar flow value, which apparently shows the fluidity of the cement paste, was large. As described above, the sufficient blackness is not obtained, and in reality, the pigment powder is not sufficiently dispersed due to the occurrence of strong magnetic agglomeration, and it seems that the color developability is remarkably reduced.

Comparative Example 3 A granulated product having an average particle size of 0.30 μm, a porosity of 0.582 and a bulk density of 0.45 g / ml was prepared in the same manner as in Example 1 except that the compression deaeration treatment was not carried out. To obtain a black pigment powder for cement coloring. Table 1 shows the mortar flow value of the obtained pigment powder for cement coloring, and the color measurement result of the cement test piece by the color difference meter.

Comparative Example 4 A granulated product having an average particle size of 580 μm, a porosity of 0.130 and a bulk density of 0.82 g / ml was prepared in the same manner as in Example 1 except that 60 g of Demol SC was used as the surfactant. To obtain a black pigment powder for cement coloring. Table 1 shows the mortar flow value of the obtained pigment powder for cement coloring, and the color measurement result of the cement test piece by the color difference meter.

In Comparative Example 4, the mortar flow value, which represents the fluidity of the cement paste, increased due to the use of a large amount of surfactant, but on the other hand, the lightness index L ^* was reduced due to insufficient dispersion in practice. Remarkably high, and sufficient blackness is not obtained.

Comparative Example 5 Instead of the cement coloring material consisting of the granulated product of Example 5, needle-shaped maghemite (average major axis diameter 0.30 μm, axial ratio 1)
2, porosity of 0.64, and bulk density of 0.35 g / ml) were directly used as a brown pigment powder for coloring cement. Table 1 shows the mortar flow value of the obtained pigment powder for cement coloring, and the color measurement result of the cement test piece by the color difference meter. During the production of the color cement, the color pigment was used in a powder state, so that the color pigment was scattered and it was difficult to handle.

[0056]

[Table 1]

[0057]

As described above, the cement coloring material according to the present invention as described above can improve the dispersibility at the time of producing color cement and can improve the fluidity of the cement paste. It is possible to improve the ease of construction and the color developability. Moreover, the material for cement coloring in the present invention is composed of a granulated product, has excellent fluidity, is very excellent in dust generation, and is easy to handle, so that the process of manufacturing a color cement is continuous, Automation can be expected.

Claims (2)

[Claims] 1. An average particle size obtained by granulating a mixture of a magnetic iron oxide pigment powder and a surfactant in an amount of 0.01 to 10% by weight based on the weight of the magnetic iron oxide pigment powder by compression deaeration treatment. Three
A cement coloring material comprising a granulated product having a porosity in the range of 0 to 1500 μm and a porosity of 0.1 to 0.3. [Equation 1] 2. A powder to be treated by adding 0.01 to 10% by weight of a surfactant to the powder of the magnetic iron oxide pigment, and mixing the surface-active agent with the powder. Is granulated by compression deaeration treatment under the condition that a linear pressure in the range of 10 to 100,000 g / cm is applied to all the powders to be treated which are stored in a fixed space in a bound state. The method for producing a cement coloring material according to claim 1.