JP6973220B2 - Deodorant for asphalt - Google Patents

Description

The present invention relates to an asphalt deodorant that effectively masks the unpleasant odor generated when heating asphalt.

In manufacturing plants for asphalt, processed oils and fats, processed rubber products, etc., various odors are generated due to the heating process. Especially in an asphalt plant, asphalt and aggregate are heated and mixed at 150 ° C to 170 ° C to produce an asphalt mixture. When asphalt is heated at a high temperature, sulfur-based components and hydrocarbon compounds contained in the asphalt are oxidized. Deterioration produces offensive odor components such as carboxylic acids and aldehydes. Especially in the case of modified asphalt, the offensive odor becomes stronger due to the deterioration of rubber and plastic in the asphalt.
As described above, since the asphalt plant involves a heating process, odors are likely to be generated, which has a great influence on the adjacent area. In addition, odor problems may occur during transportation of asphalt mixture by dump truck and at construction sites such as road pavement using asphalt.

As a countermeasure against such odors, a method is adopted in which a liquid fragrance additive containing a fragrance or the like is mixed with asphalt to mask (shield) bad odors and offensive odors and sensuously suppress those odors. (Patent Document 1). This technology introduces fragrance additives from the hatch of an asphalt tank truck and mixes them with asphalt during transportation, or directly adds fragrance additives to asphalt in an asphalt storage tank or mixer in an asphalt plant and mixes them together. It is a commonly used technique because it is possible and easy to carry out.
Further, there has been an attempt to maintain the deodorizing effect even at a high temperature by using an asphalt deodorant composition in which an inorganic substance such as silica gel is mixed with the fragrance as a holding base material for the fragrance (Patent Document 2).

Japanese Unexamined Patent Publication No. 2003-342908 Japanese Unexamined Patent Publication No. 2007-137922

However, the liquid fragrance additive described in Patent Document 1 is highly volatile, and when added to asphalt under heating, the fragrance component may volatilize in a short time and the deodorizing effect may not be maintained. Further, the deodorant composition described in Patent Document 2 is difficult to sufficiently eliminate the unpleasant odor peculiar to asphalt despite the high content of fragrance.
Therefore, an object of the present invention is to provide a deodorant for asphalt that can mask the unpleasant odor generated when heating asphalt.

As a result of diligent studies to solve the above-mentioned conventional problems, the present inventors have effectively eliminated the unpleasant odor generated when heating asphalt by using a deodorant for asphalt containing a specific fragrance component. We have found that it can be suppressed, and have completed the present invention.
That is, the present invention provides the following [1] to [3].
[1] A deodorant for asphalt, which contains at least one specific fragrance component selected from dihydromyrcenol and allyl amyl glycolate.
[2] The asphalt deodorant according to the above [1], which further contains an oil agent.
[3] The asphalt deodorant according to the above [1] or [2], which further contains a floral fragrance.

The deodorant for asphalt of the present invention can effectively mask the unpleasant odor generated when asphalt is heated even in a small amount, and can improve the working environment such as when producing an asphalt mixture and when paving a road.

Hereinafter, the present invention will be described in more detail.
In the present specification, when a preferable numerical range (for example, a range such as content) is described stepwise, each lower limit value and upper limit value can be combined independently. For example, in the description "preferably 10 or more, more preferably 20 or more, and preferably 100 or less, more preferably 90 or less", "preferable lower limit value: 10" and "more preferable upper limit value: 90" are combined. Therefore, it can be set to "10 or more and 90 or less". Further, for example, even in the description of "preferably 10 to 100, more preferably 20 to 90", it can be similarly set to "10 to 90".

[Specific fragrance ingredient]
The deodorant for asphalt of the present invention contains at least one specific fragrance component selected from dihydromyrcenol and allyl-amyl glycolate. By containing such a specific fragrance component, it is possible to effectively mask the unpleasant odor when heating asphalt.
As the specific fragrance component, either dihydromyrcenol or allyl-amyl glycolate may be used alone, or both may be used in combination. From the viewpoint of more effectively masking the unpleasant odor during heating of asphalt, it is preferable to use both dihydromyrcenol and allyl-amyl glycolate in combination.

When dihydromyrcenol and allyl amyl glycolate are used in combination, the mass ratio of dihydromyrcenol to allyl amyl glycolate (dihydromyrcenol / allyl amyl glycolate) is not particularly limited, but is preferably 20. It is / 1-1 / 2, more preferably 15/1 to 1/1, and even more preferably 10 / 1-3 / 1. By setting such a mass ratio, it is possible to more effectively mask the unpleasant odor during heating of asphalt.

The content of the specific fragrance component is not particularly limited, but is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and further preferably 0.1 based on the total amount of the deodorant for asphalt. It is 5% by mass or more, preferably 5% by mass or less, more preferably 1% by mass or less, and 0.5% by mass or less.

[Other fragrance ingredients]
The deodorant for asphalt of the present invention may contain a fragrance component other than the specific fragrance component. The other fragrance components are not particularly limited, and are, for example, fruit odor components such as ethyl acetate (pineapple odor), limonene (orange odor), and pentyl pentanate (apple odor), floral fragrances, and musk fragrances. Examples include citrus fragrances. When other fragrance components are used, 0.1 to 10% by mass is preferable, 0.5 to 5% by mass is more preferable, and 1 to 3% by mass is further preferable with respect to the total amount of deodorant.

Among the above-mentioned other fragrance components, floral fragrances are preferable. By combining the specific fragrance component of the present invention and the floral fragrance, the unpleasant odor at the time of heating asphalt can be masked more effectively.
Further, when the specific fragrance component of the present invention is combined with a floral fragrance, a combination of dihydromyrcenol and a floral fragrance is preferable from the viewpoint of suppressing an unpleasant odor during heating of asphalt for a longer period of time. It is more preferable to use a combination of the three components of allyl amyl glycolate and a floral fragrance.
The amount of the floral fragrance (floral fragrance / specific fragrance component) with respect to the specific fragrance component is preferably 1 to 30, preferably 3 to 20.

[Oil]
The asphalt deodorant of the present invention preferably contains an oil agent. By containing the oil agent, the dispersibility of the specific fragrance component and other fragrance components to be blended as needed is improved, and it becomes easy to prevent volatilization.

The type of the oil agent is not particularly limited, and examples thereof include fatty acid monoesters, fatty acid diesters, fatty acid triesters, fatty acid tetraesters, and polyalkylene glycols, and fatty acid diesters, fatty acid triesters, and fatty acid tetraesters are preferable. Among them, an oil agent having a structure in which a polyhydric alcohol having a divalent value or higher and a fatty acid are ester-bonded is preferable.

The dihydric or higher polyhydric alcohol in the oil having a structure in which a dihydric or higher polyhydric alcohol and a fatty acid are ester-bonded is, for example, 1,4-cyclohexanedimethanol, ethylene glycol, diethylene glycol, propylene glycol, or dipropylene glycol. , Divalent alcohols such as tripropylene glycol, and trihydric or higher alcohols such as trimethylolethane, trimethylolpropane, pentaerythritol, and sorbitol.

The fatty acid in the oil agent having a structure in which a divalent or higher polyhydric alcohol and a fatty acid are ester-bonded may be a saturated fatty acid or an unsaturated fatty acid, or may be a linear fatty acid or a branched fatty acid. The number of carbon atoms of the fatty acid is not particularly limited, but is preferably 6 to 30, and more preferably 9 to 24. Specific examples of fatty acids include hexanoic acid, heptanic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecanoic acid, nonadecanic acid and icosan. Saturated fatty acids such as acid, henicosanoic acid, docosanoic acid, tricosanoic acid, tetracosanoic acid, pentacosanoic acid, hexacosanoic acid, heptacosanoic acid, octacosanoic acid, nonacosanoic acid, triacanthanoic acid, hexenoic acid, heptenoic acid, octenoic acid, nonenic acid, decene Acids, undecenoic acid, dodecenoic acid, tridecenoic acid, tetradecenoic acid, pentadecenoic acid, hexadecenoic acid, heptadecenoic acid, octadecenoic acid (including oleic acid), nonadecenoic acid, icosenoic acid, henicosenoic acid, docosenoic acid, tricosenoic acid, tetracosenoic acid, Examples thereof include unsaturated fatty acids such as pentacosenoic acid, hexacosenoic acid, heptacosenoic acid, octacosenoic acid, nonacosenic acid and triacocene acid.

Among these, an oil agent having a structure in which a trihydric or higher polyhydric alcohol and a fatty acid are ester-bonded is preferable. Among such oil agents, trimethylolpropane triolate and pentaerythritol tetraolate are more preferable, and pentaerythritol tetraolate is even more preferable.

The content of the oil agent is not particularly limited, but is preferably 90% by mass or more, more preferably 94% by mass or more, still more preferably 98% by mass or more, and more preferably 98% by mass or more, based on the total amount of deodorant for asphalt. It is preferably 99.98% by mass or less, more preferably 99.95% by mass or less, and further preferably 99.9% by mass or less.

The deodorant for asphalt of the present invention can be added to asphalt to effectively mask the unpleasant odor generated when the asphalt is heated. The type of asphalt is not particularly limited, and examples thereof include straight asphalt and asphalt mixtures. The asphalt mixture generally contains straight asphalt and an aggregate composed of crushed stone, gravel, stone powder and the like, and further contains a modifier such as rubber and a thermoplastic elastomer and other additives as necessary. ..
The amount of the deodorant for asphalt of the present invention used for asphalt is not particularly limited, but is preferably 10 to 10000 ppm, more preferably 50 to 1000 ppm, still more preferably 100 to 500 ppm with respect to asphalt. It is particularly preferably 100 to 300 ppm.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited thereto.
(Preparation of deodorant)
Table 1 shows the combinations of perfume components (specific perfume components, other perfume components) and oils used in the asphalt deodorant. A deodorant was prepared by mixing the fragrance component and the oil agent and stirring them sufficiently. Using each of the prepared deodorants, a sensory test of the deodorant was carried out according to the following Examples and Comparative Examples.

<Example 1>
(1) Sensory test on straight asphalt Transfer 500 g of heated straight asphalt 60/80 (manufactured by Showa Shell Sekiyu Co., Ltd.) to a glass container and keep the temperature at 170 ° C while adding 125 mg (A-1) of deodorant for asphalt (A-1). 250 ppm) was added to straight asphalt. After stirring quickly to disperse the deodorant, the asphalt odor immediately after the addition, 1 minute after the addition and 30 minutes after the addition was sniffed, and masking evaluation (sensory test) was performed. The results are shown in Table 2.
(2) Sensory test on asphalt mixture Transfer 2 kg of heated asphalt mixture (containing 5% asphalt) to a heat-resistant bat and keep the temperature at 170 ° C while adding 25 mg (asphalt content) of deodorant for asphalt (A-1). 250 ppm) was added. After the deodorant was sufficiently blended with a scoop, the asphalt mixture immediately after the addition and 1 minute after the addition was smelled, and masking was evaluated (sensory test). The results are shown in Table 2.
[Sensory test]
In the sensory test, a total of eight panelists were asked to smell the target asphalt, and the evaluation was performed in four stages according to the following evaluation criteria.
(Evaluation criteria)
◎: Almost no asphalt odor ○: Stronger fragrance scent than asphalt odor △: Stronger asphalt odor than fragrance scent ×: Only asphalt odor

<Examples 2 to 6 and Comparative Examples 1 to 3>
A sensory test was conducted in the same manner as in Example 1 except that the type of deodorant for asphalt was changed as shown in Table 2. The results are shown in Table 2.

<Comparative Example 4>
A sensory test was carried out in the same manner as in Example 1 except that the asphalt deodorant was not used. The results are shown in Table 2.

Table 2 shows the results of the sensory test. From Examples 1 and 2, when a deodorant containing dihydromyrcenol or allyl amylglycolate, which is a specific fragrance component, was added, even a small amount could satisfactorily mask the unpleasant odor.
In Examples 3 to 4, the masking immediately after the addition was excellent by further containing floral as a fragrance component.
Further, in Example 5, when dihydromyrcenol and allyl amyl glycolate were used in combination, masking was possible even if the number of individual specific fragrance components was smaller than in Examples 1 and 2, and masking immediately after addition was excellent. Was. In Example 6, the deodorant composition of Example 5 further contained floral, which was most excellent in masking.
In Comparative Examples 1 to 3, since the deodorant composed of the fruity odor was used, the asphalt odor could not be sufficiently masked with a small amount.
In Comparative Example 4, since no additive containing a fragrance was added, the odor of asphalt was strongly felt.

Claims (2)

A asphalt deodorizing agent characterized by containing at least one particular perfume ingredient 0.1% by mass or more and oil 98 to 99.9 wt% selected from dihydromyrcenol and allyl amyl glycolate ,
The oil agent is an oil agent having a structure in which a divalent or higher polyhydric alcohol and a fatty acid are ester-bonded, the divalent or higher polyhydric alcohol is pentaerythritol, and the fatty acid is a fatty acid having 9 to 24 carbon atoms. Deodorant for asphalt . The asphalt deodorant according to claim 1, further containing a floral fragrance.