JP2974743B2 - Asphalt coloring material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an asphalt coloring material,
Specifically, the particle size suitable for color pavement is 200-3000
The present invention relates to an asphalt colorant excellent in dispersibility and color development, comprising granules having a thickness of 0.1 μm and an apparent density / true density ratio in the range of 0.14 to 0.30.

[Conventional technology]

With the development of industry and economy in Japan, the sophistication of the industrial structure and the improvement of people's lives have led to diversification and sophistication of road needs. It has been demanded.

In response to this, there has been a demand for a color pavement having a color suitable for the surrounding environment from a black asphalt pavement.

Conventionally, as for the color pavement, 5% by weight or less of asphalt coloring material (color pigment powder) is mixed with crushed stone, sand, stone powder, asphalt, etc. Paved with asphalt mixture for color pavement manufactured by mixing,
Parks, mainly for consistency with the natural environment and for aesthetic purposes,
It has been widely applied to sports facilities such as shopping malls, grounds, tennis courts, sidewalks, and housing complexes.

In general, as a method for producing asphalt mixture for color pavement, crushed stone, sand, stone powder, asphalt, etc. are directly mixed into a mixer containing an asphalt mixture obtained by previously kneading, and kneading, A method of coloring asphalt mixture has been adopted.

The asphalt coloring material used in the above-mentioned production method is in the form of fine particles, and therefore, when the kraft paper bag containing the asphalt coloring material is unpacked, or when the pigment is sharply scattered when put into a mixer, In addition, since the asphalt coloring material itself is poor in fluidity and rich in adhesion, when the asphalt coloring material is put into a mixer with a bucket (elevator, belt conveyor) or the like, the asphalt coloring material easily adheres to the inside of the bucket or other equipment. These inconveniences in handling have caused many troubles in the production of asphalt mixture for color paving.

In addition, when the asphalt coloring material is put into the mixer at one time, the asphalt coloring material becomes “mamako” or “floats” on the surface of the asphalt mixture, thereby dispersing and coloring the asphalt mixture. And the kneading time is inevitably lengthened.

(If the asphalt mixture is mixed and colored with the asphalt coloring material, a state in which an asphalt mixture having a color close to the color of the asphalt coloring material used is obtained is referred to as having excellent coloring properties.) In addition, when the asphalt coloring material is charged into the mixer in the above-described production method, usually, the kraft paper bag containing 5 kg to 25 kg is unpacked and the asphalt coloring material is manually input, or into a vinyl bag. A so-called batch method is adopted in which the filled asphalt coloring material is put into a mixer together with the bag by hand.

As a prior art for solving the problems such as dispersibility of the color pigment, prevention of scattering and prevention of adhesion to other equipment, it is a technique in a technical field different from that of the present invention, but is a technique in a welding type road display material field. In addition, a technique has been proposed in which a color pigment and a natural or synthetic resin are uniformly melt-mixed, and then a granular pigment obtained by quenching and solidifying is used (for example,
JP-A-54-37136, JP-A-54-161644).

[Problems to be solved by the invention]

As mentioned above, when manufacturing asphalt mixture for color pavement, asphalt coloring materials require special attention in handling compared to crushed stone, sand, stone powder, asphalt, etc., and asphalt coloring materials are easier to handle. At the same time, it has been the greatest technical problem in the asphalt mixture for color pavement industry to have excellent dispersibility and color development in asphalt mixture.

[Means for solving the problem]

The present inventors have developed an asphalt coloring material (color pigment powder) used for producing an asphalt mixture for color pavement, which is excellent in dispersibility and color development in an asphalt mixture, and is easy to handle. As a result of various studies to solve the above technical problems, the present invention has been completed.

That is, the present invention is an inorganic color pigment powder or a mixture of the inorganic color pigment powder and the extender or the inorganic color pigment powder, after consolidating any one of the mixture obtained by adding a surfactant to the mixture. It is an asphalt coloring material composed of granules having a particle size of 200 to 3000 μm and a ratio of apparent density / true density in a range of 0.14 to 0.30.

Next, conditions for implementing the present invention will be described.

As the inorganic color pigment powder in the present invention, α-Fe ₂ O
₃ , inorganic pigment powders such as γ-Fe ₂ O ₃ , Fe ₃ O ₄ , yellow iron oxide (α-FeOOH), titanium oxide, graphite, chromium oxide, cadmium yellow and chrome yellow can be used.

The asphalt coloring material in the present invention has a particle size of 200 to 300.
0 μm, and the value of the ratio of apparent density / true density is 0.14 to 0.30
Of the granules within the range of

When the particle size is less than 200 μm, a problem of scattering of the asphalt coloring material occurs, and the working environment is deteriorated. If it exceeds 3000 μm, it takes time to disperse the asphalt coloring material into the asphalt mixture, which is not economically preferable.

When the value of the ratio of apparent density / true density is less than 0.14, it becomes an asphalt coloring material composed of a granulated substance having low strength, easily returns to the original powder state, and cannot prevent the scattering property. On the other hand, when the value of the ratio of apparent density / true density exceeds 0.30, since it has been subjected to strong consolidation treatment, it becomes an asphalt coloring material composed of a strong granulated material, and can prevent scattering. It takes a long time to uniformly disperse the asphalt coloring material in the asphalt mixture, and the color developability is unfavorable.

In order to further improve the dispersibility of the asphalt coloring material of the present invention, the coloring property, an inorganic pigment pigment powder before compaction treatment is added with an extender pigment or a surfactant or an extender pigment and any one of a surfactant and mixed. Is also good.

As extenders in the present invention, SiO ₂ , Al ₂ O ₃ and C
An extender pigment containing at least one of aCO ₃ can be used. For example, there are clay, silica powder, talc, diatomaceous earth, lime and the like. The extender pigment is preferably added in such a range that the extender pigment accounts for 3 to 50% by weight based on the total amount of the inorganic coloring pigment powder and the extender pigment.

If the amount exceeds 50% by weight, the coloring power to the asphalt mixture is undesirably reduced.

As the surfactant, a cationic, anionic, nonionic or amphoteric surfactant can be used.

For example, metal soaps mainly containing fatty acid alkali metal salts such as calcium stearate, magnesium stearate, etc., rosin soaps, naphthenic acid soaps, poly (ethylene oxide) alkyl ether phosphates, polyoxyethylene alkyl phenol ether phosphates , Polyoxyethylene alkylamine salts, sodium lauryl sulfate and stearyl dimethyl betaine.
The addition amount is preferably in the range of 0.01 to 5% by weight based on the inorganic color pigment powder or the mixture of the inorganic color pigment powder and the extender pigment.

If it exceeds 5% by weight, it is difficult to granulate the granules having an appropriate strength, and the obtained granules are fragile, so that the scattering of the asphalt colorant cannot be prevented.

In order to obtain an asphalt coloring material comprising granules having a particle diameter of 200 to 3000 μm and an apparent density / true density ratio of 0.14 to 0.30 in the present invention, an inorganic coloring pigment powder or It is necessary to consolidate either the mixture of the inorganic color pigment powder and the extender pigment or the inorganic color pigment powder or the mixture obtained by adding a surfactant to the mixture.

Pressing press, roll press,
Tableting machine, briquetter, sand mill, simpson mill,
A mix muller and a raikai machine can be used.

If the asphalt coloring material obtained by the consolidation treatment is in a flake state, then it is appropriately crushed and sized to form a granulated material having an arbitrary particle size according to the application, whereby the fluidity is improved, and An asphalt coloring material which is very easy to handle and has excellent dusting properties.

[Action]

First, the most important point in the present invention is that any one of the inorganic color pigment powder or the mixture of the inorganic color powder and the extender or the inorganic color pigment, and any one of the mixture obtained by adding and mixing the surfactant is mixed. If the particle size is 200-300
0 μm, and the value of the ratio of apparent density / true density is 0.14 to 0.30
Excellent dispersibility and color development of granules within the range of
Moreover, it is a fact that an asphalt coloring material which does not cause troubles such as scattering of the coloring pigment powder and adhesion to other equipment is obtained.

In addition, the asphalt coloring material made of the granulated material has excellent fluidity and is easy to handle, so that the process of manufacturing the asphalt mixture for color pavement can be continuous and automated.

In the present invention, the reason why an asphalt colorant excellent in dispersibility and color developability is obtained is not yet clear, but the present inventor thinks as follows.

That is, by consolidating the inorganic color pigment powder,
As the air between the colored pigment powders is degassed, and at the same time, the bonding state caused by the sintering of the pigment particles due to heat treatment and the interaction between the particles can be decomposed and dissolved, so asphalt mixture for pavement production The wettability of the asphalt sometimes used to the colored pigment powder is improved, and an asphalt coloring material excellent in dispersibility and coloring is obtained.

If necessary, an extender pigment or a surfactant or any of an extender pigment and a surfactant may be added to and mixed with the inorganic color pigment powder in the present invention.

By adding and mixing the extender or the surfactant, or any of the extender and the surfactant, the dispersibility and coloring of the asphalt coloring material obtained can be further improved.

In particular, when the extender pigment and the surfactant were added and mixed, at the time of mixing with the inorganic color pigment powder before the consolidation treatment, the extender disintegrated the aggregates in the color pigment powder, and then was loosened It is believed that the effective attachment of the surfactant to the particle surface results in better asphalt wetting of the color pigment powder, and further improved dispersibility and color development. I have.

〔Example〕

 Next, the present invention will be described with reference to Examples and Comparative Examples.

In the following Examples and Comparative Examples, as for the color developing properties, the asphalt coloring material was dissolved in the asphalt mixture, the resulting asphalt mixture was observed, and the color closer to the color of the used asphalt coloring material was observed. Present.
○ ‥‥ The color is close to the color of the asphalt coloring material used. △ ‥‥ Shows the same color as the conventional product. × ‥‥
Granules remain in the asphalt mixture. Was evaluated.

Example 1 First, 500 g of iron oxide powder (Fe ₂ O ₃ : average particle size 0.15 μm) was used as an inorganic color pigment powder, and the iron oxide powder was subjected to a consolidation treatment using a roll press. The processing passage time is
90 seconds. Subsequently, by crushing and classifying, the particle size is 500 to 710 μm, and the value of the ratio of apparent density / true density is 0.
Asphalt coloring material consisting of 20 granules was obtained.

50 g of the asphalt coloring material obtained was mixed with an asphalt mixed material (stone crushed 24) in which the surface of the aggregate was covered with asphalt.
% By weight, sand 68% by weight, stone powder 2% by weight, asphalt 6% by weight) and kneading operation at a kneading temperature of 160 ° C. to obtain a reddish brown asphalt mixture for color paving. In this case, the time required for dissolving the asphalt coloring material in the asphalt mixture and completing the uniform dispersion of the iron oxide powder was measured, and the result was 77 seconds.

The color of the asphalt mixture obtained was a color close to the color of the asphalt coloring material (iron oxide) used, and the color development was excellent.

The asphalt coloring material did not scatter or adhere to other equipment.

Examples 2 to 10 Exactly the same as Example 1 except that the amount of the inorganic color pigment powder, the type and amount of the extender, the type and amount of the surfactant, the type of the consolidation device and the processing passage time were variously changed The particle size is 200 to 3000 µm, and the value of the apparent density / true density ratio is
An asphalt colorant consisting of granules in the range of 0.14 to 0.30 was obtained.

Then, a reddish brown asphalt mixture for color paving was obtained in exactly the same manner as in Example 1 using the obtained asphalt coloring material. In this case, the asphalt coloring material was dissolved in the asphalt mixture, and the time required for the iron oxide powder to be uniformly dispersed was completed.
It was shown to. Also in these cases, the asphalt coloring material did not scatter or adhere to other facilities.

The consolidation time in Examples 2 and 3 was 14
8 seconds, 58 seconds. In Example 10, a sand mill was used as a consolidation treatment device. The consolidation time at that time is
60 minutes.

Comparative Example 1 An asphalt mixture for color pavement shown in Example 1 using an inorganic colored pigment powder (Fe ₂ O ₃ : average particle size 0.15 μm) instead of the asphalt colorant composed of the granulated product of Example 1 A red-brown asphalt mixture for color pavement was obtained according to the production method described above. Table 1 shows the results of measuring the time required for uniformly dispersing the iron oxide powder in the asphalt mixture in this case and the coloring properties.

In the production of the asphalt mixture for color pavement, since the inorganic color pigment was used in a powder state, the color pigment was scattered and adhered to equipment of other facilities.

Comparative Example 2 The iron oxide powder (Fe ₂ O ₃ : average particle diameter used in Example 1)
An asphalt coloring material consisting of a granulated product was obtained in the same manner as in Example 1 except that 500 g of (0.15 μm) was used and the iron oxide powder was subjected to consolidation treatment by a roll press machine with a treatment passage time of 250 seconds.

Using the obtained asphalt coloring material, a reddish brown asphalt mixture for color paving was obtained in exactly the same manner as in Example 1. Table 1 shows the results of measuring the time required for uniformly dispersing the iron oxide powder in the asphalt mixture in this case and the coloring properties.

[Effects of the Invention] The asphalt coloring material according to the present invention can improve the dispersibility at the time of producing an asphalt mixture for color pavement, and at the same time, can enhance the color developability, as shown in the above-described examples. . In addition, the asphalt coloring material of the present invention is made of a granulated material, has excellent fluidity, and is easy to handle. Therefore, it is expected that the process of manufacturing the asphalt mixture for color pavement will be continuous and automated.

Continuation of front page (72) Inventor Yasuhiko Fujii 4-1-2, Funariminami, Naka-ku, Hiroshima-shi, Hiroshima Examiner, Toda Kogyo Co., Ltd. Creative Center Yumiko Isshiki (56) References JP-A-53-16028 (JP, A) JP-A-1-165666 (JP, A) JP-B-49-10811 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08L 95/00 C08K 3/00-13 / 08

Claims (3)

(57) [Claims] The particle diameter of the inorganic color pigment powder after compaction treatment is 200 to 3000 μm, and the ratio of apparent density / true density is
Asphalt coloring material comprising granules in the range of 0.14 to 0.30. 2. The method according to claim 1, wherein the extender pigment is added to and mixed with the inorganic color pigment powder so that the extender pigment accounts for 3 to 50% by weight based on the total amount of the inorganic color pigment powder and the extender pigment. The asphalt coloring material according to 1. 3. The asphalt colorant according to claim 1, wherein 0.01 to 5% by weight of a surfactant is added to and mixed with the inorganic color pigment powder or a mixture of the inorganic color pigment powder and the extender pigment.