JP2011001500A - Asbestos fiber scattering preventive agent and method of preventing scattering of asbestos fiber using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an asbestos fiber scattering preventive agent, which effectively attains prevention of scattering of asbestos fibers for a long time.SOLUTION: Prevention of scattering of asbestos fibers is attained by the asbestos fiber scattering preventive agent which includes a colloid dispersion having a silica sol dispersed in water, and has such a fiber bundling ability that the agent adheres to asbestos fibers and reacts with an alkaline earth metal ion to mutually bond the asbestos fibers.

Description

  The present invention relates to an asbestos fiber scattering prevention treatment agent applicable to an asbestos-containing layer on an asbestos construction surface, and an asbestos fiber scattering prevention method using the same.

  Asbestos (asbestos) fibers, durability, heat resistance, insulation resistance, chemical resistance, and excellent in various physical properties such as electrical insulation, building materials, electric appliances, have been used in a wide range of fields such as automobiles. Specifically, asbestos fiber was constructed as a functional material in the building, and an asbestos-containing layer was formed in the existing building. In such an existing building or the like, when any external force is applied to the asbestos-containing layer, asbestos fibers are detached from the asbestos-containing layer and scattered in the air. Further, even when the asbestos fibers lumps was peeled dropped during removal operation of the asbestos-containing layer from asbestos construction surface, as in the case where external force is exerted, fine asbestos fibers from scattering in the air. As a result of such scattering, workers who remove the asbestos-containing layer are exposed to asbestos, and the surrounding environment is contaminated with asbestos. Asbestos fiber is said to be harmful because it increases the probability of inducing mesothelioma and lung cancer after a long incubation period when inhaled into the lungs. According to the definition of the World Health Organization (WHO), such harmful asbestos fibers are fine minerals having a length of 5 μm or more, a width of less than 3 μm, and an aspect ratio of 3 or more.

  In order to prevent the occurrence of health problems such as mesothelioma due to harmful asbestos, preventive measures against asbestos constructed in existing buildings have been established by law.

  As a method of constructing asbestos-containing materials as building materials, asbestos-containing layers are formed by spraying and applying a slurry obtained by kneading asbestos-containing materials wet to the wall surface, asbestos-containing boards (asbestos-containing boards) Construction methods such as a method of attaching to a wall are popular. Thus, it is important as an asbestos fiber scattering prevention measure to perform the asbestos fiber scattering prevention process with respect to the existing asbestos about the existing building etc. in which the asbestos containing material was constructed. For such asbestos fiber scattering prevention measures, the asbestos construction surface is impregnated with an asbestos fiber scattering prevention treatment agent (sometimes referred to as a treatment agent), or a coating film is formed on the asbestos construction surface surface, so that the asbestos-containing layer is coated with asbestos. There are a treatment for preventing the fibers from scattering, a so-called containment treatment, and a removal treatment for peeling and removing the asbestos-containing layer and the asbestos-containing board from the construction surface.

  The removal treatment is usually carried out by spraying water or a treatment liquid on the asbestos construction surface to wet the asbestos to remove the asbestos-containing layer. However, asbestos has a specific vast surface area but is poor in water retention. Therefore, once the asbestos is wet, the drying speed is fast, and it is difficult to reliably prevent the asbestos fibers from being scattered by a normal removal process.

  In addition, the asbestos construction surface shows the hydrophobic properties peculiar to asbestos, so the penetration of the treatment liquid into the asbestos-containing layer is often slow, and it is difficult to uniformly infiltrate the treatment liquid throughout the asbestos-containing layer. There are cases. There is a problem in that the asbestos fibers are scattered at a site where the penetration of the treatment liquid to the asbestos construction surface is not achieved due to the hydrophobic property.

  In addition, since the asbestos-containing layer forms a characteristic filter structure, formation of a coating film on the treated surface can be achieved with a high-viscosity treatment liquid or a complex treatment liquid containing a micron-order inorganic substance. However, there is a problem that the treatment liquid cannot be penetrated or impregnated into the asbestos-containing layer.

  In order to deal with these various problems, as a measure to prevent asbestos fiber scattering from the existing asbestos-containing layer, a water-soluble treatment agent containing a thickener in a natural polymer such as gum arabic is sprayed onto the asbestos-containing layer. A method of supplying, wetting and fixing has been proposed (Patent Document 1).

  As measures for preventing asbestos fiber scattering similar to the above, a composition for preventing asbestos scattering by a fine polymer such as an acrylic emulsion characterized by a high viscosity with a synthetic polymer and a treatment method for impregnating the inside of the asbestos-containing layer have been proposed. (Patent Document 2).

  In addition, as a measure to prevent asbestos fibers from scattering, the primary treatment agent impregnates and solidifies a hardener with a silicon-based resin on the surface of the asbestos-containing material, the secondary treatment impregnates a synthetic polymer-based penetrant, and the tertiary treatment impregnates the upper part. In addition, a method for preventing asbestos scattering by forming a laminated structure coated with an organic-inorganic composite material has been proposed (Patent Document 3).

  Furthermore, as a measure for preventing asbestos fiber scattering, in addition to the above-described method, a method for spraying a water-soluble inorganic binder into the space to be treated and attaching it to the surface of the asbestos fibers to bond the asbestos fibers to each other to achieve the prevention of scattering. Has been proposed. In this method, the asbestos-containing layer is then coated with a fireproof spraying material (Patent Document 4).

JP 2008-12471 A JP 2007-92017 A JP 2006-63299 A JP 2007-247240 A

  The asbestos-containing layer that is the target of the asbestos fiber scattering prevention treatment is a combination of microscopically fine and long-fiber asbestos that are intertwined in a three-dimensional complex with relatively coarse cement, and the addition of water. In many cases, the mixed slurry is formed as a sprayed layer by spray coating using a dedicated machine. The formed spray layer forms a structure with a very high porosity due to the tensile strength specific to asbestos fibers. In addition, examples of the target of the asbestos fiber scattering prevention treatment include boards made by paper-making the above mixed slurry, and these molded bodies also form the same structure as the asbestos-containing layer. . Since the asbestos-containing layer and the formed body are composed of the composition as described above, there is no aggregate that is the axis of expression of mechanical strength, the bulk specific gravity is remarkably low, and the mechanical strength is Very low. For this reason, the asbestos-containing layer and the formed body are very weak in bonding strength between the asbestos fibers, and the asbestos fibers easily become free single fibers due to weak external forces and stimuli and are easily scattered.

  The asbestos-containing layer formed using asbestos fibers as the main material has a microscopically characteristic fine structure and a large specific surface area, and thus exhibits a hydrophobic tendency. Moreover, in the existing building in which the asbestos-containing layer is formed, there is a portion that exhibits strong hydrophobicity depending on various use situations of the building or various processes after the asbestos-containing layer is formed. For this reason, many asbestos-containing layers have poor penetration or wettability with respect to the treatment liquid, and many treatment agents used for asbestos fiber scattering prevention treatment are difficult to penetrate into the asbestos-fiber scattering layer, and have the effect of preventing asbestos fiber scattering. There is a problem that it is difficult to achieve sufficiently.

  High-viscosity natural or synthetic resin-based polymer processing agents used in the methods of Patent Documents 1 and 2, and ceramic particles such as titanium oxide and alumina hydroxide used in the method of Patent Document 3 Inorganic-organic composite processing agents containing inorganic substances of the order are difficult to penetrate into the asbestos-containing layer due to the filter action at the surface layer of the asbestos-containing layer, and are applied during the asbestos fiber scattering prevention treatment. These treatment agents will only form a coating on the surface of the asbestos-containing layer. As described above, the asbestos-containing layer has a very fragile structure. For this reason, the coating film on the surface of the asbestos-containing layer is easy to peel off, and there is a problem that it is difficult to achieve asbestos fiber scattering prevention over a long period of time.

  In addition, the water-soluble inorganic binder sprayed into the treatment space by the method disclosed in Patent Document 4 has a higher viscosity than that of fresh water, and the surface tension is not adjusted. There is a defect that there is an asbestos fiber part which is not easily penetrated and is not bonded by a binder in the scatterable asbestos fiber or the asbestos-containing layer, and asbestos fiber scatter prevention cannot be sufficiently achieved.

  By the way, the asbestos-containing layer is often provided in a building as a member having some function. For example, the asbestos-containing layer may be formed as a layer having a heat retaining function in a building constructed in a cold region where the temperature is below freezing. When asbestos fiber scattering prevention treatment is to be performed on asbestos provided in such an existing building, the temperature is below freezing point (0 ° C or below) during storage and construction of the asbestos fiber scattering prevention treatment agent. Can happen. In such a case, the processing liquid may freeze. When the processing liquid is frozen, the liquidity of the processing liquid may change. Therefore, in order to be able to carry out the asbestos fiber scattering prevention treatment under any low temperature atmosphere, development of a cotton fiber scattering prevention treatment agent that can be used even in cold regions is required.

  In addition, asbestos-containing layers are often difficult to carry out asbestos fiber scattering prevention processing, such as narrow spaces such as the back of the ceiling or elevator shafts, special closed spaces, or high places such as factories and warehouses. In addition, in the conventional asbestos fiber scattering prevention treatment method, a portable measuring instrument such as a moisture content measuring instrument is used as a method for confirming the progress of the treatment in the processing target part or confirming the completion (completion) of the treatment. The contact method used is employed. Therefore, it is very difficult to confirm the details of the processing target part, and this is accompanied by the danger of the confirmation of the processing target part, and the work efficiency of the conventional asbestos fiber scattering prevention processing method is reduced. Low and high cost.

  The present invention has been made in view of the above problems, an asbestos fiber scattering prevention treatment agent capable of effectively achieving asbestos fiber scattering prevention over a long period of time, a treatment agent applicable even in cold regions, and An object of the present invention is to provide a treatment agent that enables easy confirmation of the processing target part. Furthermore, this invention also aims at provision of the asbestos fiber scattering prevention method using those processing agents.

The asbestos fiber scattering prevention treatment agent of the present invention comprises a colloidal dispersion of silica sol, and adheres to asbestos fibers, reacts with alkaline earth metal ions, and has a fiber binding ability to join asbestos fibers to each other. The treatment agent is supplied to the asbestos-containing layer by spraying to penetrate into the details in the layer, and reacts with the alkaline earth metal ions (Ca ²⁺ , Mg ²⁺ ) contained in the asbestos-containing layer, thereby producing a viscous material. It turns into a gel. This phenomenon indicates that an adhesive layer is formed on and around the surface of the asbestos fibers contained in the asbestos-containing layer, from the state where the asbestos fibers float individually to the state where the asbestos fibers are adhesively bonded to each other. It shows that the reforming of (primary reforming) was achieved.

  The gel in the asbestos-containing layer is present on and around the surface of the asbestos fiber, and a dry gel is formed through a dehydration reaction at a portion where the alkaline earth metal ion concentration is low in the object on which the asbestos-containing layer is formed. Further, in the object in which the asbestos-containing layer is formed, a compound having a binding ability (C—S—H: calcium silicate hydrate) is generated by a pozzolanic reaction at a portion where the alkaline earth metal ion concentration is high. In the reaction system that generates this dehydration reaction or pozzolanic reaction, an insoluble coating layer is formed on the asbestos fibers by the progress of these reactions or drying, and the asbestos fibers are bound together by bonding of the coating layers. The modification (secondary modification) from the state in which the asbestos fibers are adhesively bonded to each other to the state in which the asbestos fibers are bound together through a mutually insoluble coating is achieved. Thus, the asbestos fiber scattering prevention treatment agent of the present invention achieves the primary modification and the secondary modification and has fiber binding ability.

  The product produced by the pozzolanic reaction is excellent in heat insulation, heat resistance, water resistance, and weather resistance, and the coating layer made of dried gel has excellent heat resistance, water resistance, chemical resistance, and weather resistance. Have

  Moreover, the asbestos fiber scattering prevention treatment agent of the present invention is made of a colloidal dispersion of silica sol belonging to the finest substance in the industry, and the particle diameter of silica sol is preferably 5 nm to 100 nm.

  Moreover, it is preferable that content of the silica sol in the colloid dispersion liquid which makes the asbestos fiber scattering prevention processing agent of this invention is 1.0 weight%-20.0 weight%.

  The treatment agent for preventing asbestos fiber scattering of the present invention preferably has a viscosity such that the flow time in a 3 mm cup by the flow cup method of JIS K 5600-2-2 is 30 seconds or less.

  Furthermore, it is preferable to add a surfactant to the asbestos fiber scattering prevention treatment agent. Examples of the surfactant added to the asbestos fiber scattering prevention treatment agent include nonionic surfactants and anionic surfactants.

  It is preferable that ethanol is added to the asbestos fiber scattering prevention treatment agent of the present invention.

  It is preferable that a fluorescent pigment is added to the asbestos fiber scattering prevention treatment agent of the present invention.

  Further, the present invention is an asbestos fiber scattering prevention method, wherein an asbestos fiber scattering prevention treatment agent is sprayed on an asbestos construction surface to wet the asbestos fibers by the treatment agent, and the treatment agent is permeated into the asbestos-containing layer. Asbestos fibers are bonded together.

  In the asbestos fiber scattering prevention method, when the asbestos fiber scattering prevention treatment agent is sprayed on the asbestos construction surface, the treatment agent is sprayed in a thick mist in advance in the work space, and the scattered asbestos fibers are moistened to remove the asbestos fibers. It is preferable to make it a scattered state.

  The asbestos-containing layer with asbestos construction surface to Hallam the risk of scattering of asbestos fibers, the reformed into asbestos-containing layer with a safe and beneficial functional for a long time, on the occasion asbestos fiber scattering prevention treatment, spray It is required that the asbestos fiber scattering prevention treatment liquid supplied by the method has excellent permeability and a function of changing to a stable substance at the permeated site. In this regard, according to the asbestos fiber scattering prevention treatment agent of the present invention, the treatment agent penetrates into the details in the asbestos-containing layer by spraying the treatment agent to the asbestos-containing layer, and in the asbestos-containing layer Due to the reaction between the alkaline earth metal ions contained in the asbestos-containing layer and the treatment agent, a gelation reaction occurs on the surface of the asbestos fiber and its surroundings, and a reaction product (C—S—H; Asbestos fibers can be joined to each other by the formation of calcium silicate hydrate). Thereby, according to this invention, it becomes possible to achieve effectively the prevention of asbestos fiber scattering over a long period of time. Thus, according to the treatment agent of the present invention, the treatment agent penetrates to the details of the asbestos-containing layer, and the above reactions occur in the entire area of the asbestos-containing layer, so that the binding group of asbestos fibers becomes the entire area of the asbestos-containing layer. As a result, the prevention of scattering of asbestos fibers can be achieved stably and effectively, and the exposure of workers engaged in the processing of the asbestos-containing layer and the contamination of the surrounding environment can be prevented.

  Moreover, the asbestos fiber scattering prevention processing agent of this invention can achieve the penetration | infiltration of a processing agent to the surface of the asbestos fiber contained in an asbestos content layer effectively because the particle diameter of a silica sol is 5-100 nm. .

  In addition, the asbestos fiber scattering prevention treatment agent of the present invention has a silica sol content of 1.0 wt% to 20.0 wt%, so that the low viscosity and penetrating functionality of the colloidal dispersion can be maintained. Asbestos fiber mutual binding force can be achieved.

  The asbestos fiber scattering prevention treatment agent of the present invention has the viscosity that the flow-down time by the flow cup method is 30 seconds or less, so that it has liquidity equivalent to fresh water, and contains asbestos compared to the conventional treatment agent. Excellent permeability to the layer.

  Further, by adding a surfactant to the asbestos fiber scattering prevention treatment agent, the permeability is improved by adjusting the surface tension and improving the wettability to the asbestos fibers. At this time, when the surfactant is a nonionic surfactant or an anionic surfactant, the stability of the colloidal dispersion of silica sol can be maintained well.

  When ethanol is added to the asbestos fiber scattering prevention treatment agent of the present invention, the added ethanol exhibits a function as a freezing adjuster in the asbestos fiber scattering prevention treatment agent, and the liquidity of the asbestos fiber scattering prevention treatment agent The risk of change can be suppressed. Therefore, it is possible to suppress the possibility of a decrease in liquid properties and performance of the treatment agent due to freezing of the colloidal dispersion during storage or construction in a cold region.

  Ethanol, which gives antifreeze function to asbestos fiber anti-scattering treatment for the purpose of environmental protection, is not applicable to organic solvent poisoning prevention regulations and PRTR law. The solvent is also excluded from the fourth class, and the diluted solution ensures high safety regardless of where it is used.

  Specifically, in the case of 30% aqueous solution, ethanol added to the treatment agent (freezing-resistant treatment agent) so that it can be suitably used for cold districts has a freezing temperature of 21.0 ° C. below zero, 50 In the case of a% aqueous solution, it is 38.0 ° C. below zero, indicating a very low freezing temperature. Therefore, the risk of freezing can be effectively suppressed by mixing the asbestos treatment agent for cold regions with ethanol having the characteristics of a low freezing temperature as described above.

  By confirming the progress or achievement (completion) of the spraying treatment of the treating agent, the asbestos fiber scattering preventing treating agent of the present invention is a fluorescent pigment added (sometimes referred to as a luminescent treating agent). Can be easily implemented. For the fluorescent pigment, a light-emitting treatment agent having a light-emitting function is used by irradiating the region of the construction part, which is a part where the treatment agent is applied to the asbestos-containing layer, with a black light (light having a wavelength of 300 nm to 450 nm).

  That is, the luminescent treatment agent of the present invention can be used by irradiating the area where the spraying work is performed and its surroundings with black light during the spraying process on the asbestos-containing layer using various sprays or the like. , By observing the light emission luminance due to the fluorescent pigment contained in the luminescent treatment agent, the boundary between the area where spraying has been performed and the area where it has not been performed is clarified, and the progress of the asbestos fiber scattering prevention process can be confirmed or Confirmation of achievement can be easily realized. In addition, the above-mentioned progress confirmation or achievement confirmation can be achieved with higher accuracy by combining the irradiation method with the luminescent treatment agent and the black light and the management equipment such as the conventional moisture content measuring device. .

  In addition, comparing asbestos fiber confinement treatment (asbestos fiber scattering prevention treatment) before and after the asbestos construction surface to be treated with the treatment agent of the present invention is compared with physical properties after treatment, asbestos scattering prevention. The surface to be processed that realizes the above in a more stable manner is formed. Before and after carrying out the spraying treatment of the treatment liquid on the surface to be treated in performing the removal treatment (asbestos-containing layer removal treatment) of the asbestos fiber layer having the asbestos construction surface to be treated by the treatment agent of the present invention. Even in the case of comparison, a surface to be processed that realizes stabilization in terms of physical properties is formed after implementation.

  Furthermore, since the asbestos fiber scattering prevention method and the asbestos-containing layer removal method of the present invention use a treatment agent that is excellent in permeability and processing ability, there is an effect that the processing construction cost can be reduced.

  In asbestos fiber scattering prevention method and asbestos-containing layer removing method, when the processing of asbestos fibers scattered state, ceiling and walls or space of the room in which asbestos fibers are scattered or sprayed asbestos treatment agent around the time The asbestos fibers that are scattered are absorbed by the water droplets by contacting the droplets with high wettability, and the asbestos fibers are settled by the action accompanying the drop of the droplets. Dust generation is achieved. This is derived from the first modification described above.

  Furthermore, in the asbestos fiber scattering prevention method and the asbestos-containing layer removal method, the asbestos-containing layer is obtained by the asbestos wetting by the droplets of the sprayed treatment liquid adhering to the asbestos-containing layer, and further by the fiber binding ability by drying. By modifying the surface layer of the asbestos fiber, the asbestos fiber is stably brought into a non-scattered state. This shows that effective exposure prevention measures are realized. This is due to the secondary reforming described above.

  And in carrying out the asbestos fiber scattering prevention method and the asbestos-containing layer removal method, the safety of the work space can be maintained for a long time by dedusting the asbestos fibers as described above and making the asbestos fibers non-scattered. Secured.

  In the implementation of the asbestos fiber scattering prevention method and the asbestos-containing layer removal method, if an asbestos fiber scattering prevention treatment agent added with ethanol is used as the treatment liquid, the treatment agent will freeze during storage or construction in cold regions. The possibility that the processing performance of the asbestos-spattering prevention treatment of the processing liquid may be reduced is suppressed. Specifically, the asbestos fiber scatter prevention treatment using the asbestos fiber scatter preventive agent added with ethanol ensures the same asbestos fiber scatter prevention effect even under a room temperature of 10.0 ° C. .

  In the implementation of the asbestos fiber scattering prevention method and asbestos-containing layer removal method, if a fluorescent treatment agent is used as the treatment liquid, after the light emission treatment agent is sprayed on the asbestos-containing layer, black is applied to the sprayed site. When the light is irradiated, the portion emits a fluorescent color, so that the concentration and distribution of the light-emitting treatment agent can be confirmed. In this way, by confirming the progress of spraying construction by irradiation of black light, the site where the asbestos fiber scattering prevention method and the asbestos-containing layer removal method are to be applied can be used to check the construction progress status such as narrow places and high places. Even if it is a case where it is difficult to confirm, it is possible to efficiently check the progress of the asbestos fiber scattering prevention treatment work or the like or the achievement of such treatment work. Moreover, since the progress of the spraying construction can be visually confirmed by the irradiation of the black light, it can be transmitted / received or stored as digital data by an image such as a video as necessary. Therefore, the use of a fluorescent treatment agent as a treatment liquid provides a highly safe confirmation method as a confirmation method of progress of asbestos fiber scattering prevention treatment work, etc., and also improves the reliability of the work. In addition, there is an effect that the cost of comprehensive processing construction can be reduced.

(A) is a schematic diagram showing asbestos fibers, (B) is a schematic diagram showing a state where the treatment agent of the present invention adheres to the asbestos fibers to wet the fibers, and joins and binds the fibers together. (C) is a schematic view showing a state in which the treatment agent of the present invention binding asbestos fibers is dried to form a hard coating, and the asbestos fibers are bound by this hard coating. . (A) is a phase-contrast micrograph showing asbestos fibers before being subjected to asbestos fiber scattering prevention treatment with the treatment agent of the present invention, and (B) is subjected to asbestos fiber scattering prevention treatment with the treatment agent of the present invention. It is a phase-contrast micrograph which shows the asbestos fiber after. (A) is a scanning photomicrograph showing an asbestos-containing layer before the asbestos fiber scattering prevention treatment with the treatment agent of the present invention, and (B) is an asbestos fiber scattering prevention treatment with the treatment agent of the present invention. It is a scanning microscope picture which shows the asbestos content layer after having performed. It is a graph which shows the change of surface tension by addition of surfactant to fresh water and dispersion B. The numerical values in the table indicate the amount of surfactant added. The amount added is 1/100 of the numerical value. It is a graph which shows the drying behavior of the wet asbestos content layer.

  The asbestos fiber scattering prevention treatment agent of the present invention comprises a colloidal dispersion of silica sol. The silica sol is made of silicon dioxide, or contains silicon dioxide as a main component and contains oxides of alkali metals (lithium, sodium, potassium).

  The outline | summary of reaction in the asbestos containing layer of the asbestos fiber scattering prevention processing agent of this invention is shown below. By supplying the treatment agent of the present invention, whose viscosity and surface tension are adjusted, to the asbestos-containing layer by spraying, the treatment agent quickly penetrates into the details in the asbestos-containing layer. The infiltrated treatment agent quickly changes to a viscous gel on and around the surface of the asbestos fiber by the action of the alkaline earth metal ions derived from the asbestos and cement contained in the asbestos-containing layer. A non-scattered state in which the fibers are joined together is formed, and the state of the asbestos-containing layer is modified (primary modification).

  In addition, the silica sol is fine and highly active, and when the treatment agent of the present invention is sprayed and applied to the portion containing the alkaline earth metal ions at a high concentration in the asbestos-containing layer (high concentration portion), the high concentration In this part, alkaline earth metal ions and highly active silica sol cause a pozzolanic reaction to produce a precursor of a compound having a bonding ability (C—S—H: calcium silicate hydrate). As the pozzolanic reaction proceeds, crystallization of the pozzolanic reaction compound proceeds, and a bonding layer is formed in the high concentration portion. On the other hand, the polycondensation reaction proceeds due to the progress of dehydration in the viscous gel, and a coating layer that binds asbestos fibers is formed in the portion of the asbestos-containing layer where the dehydration of the gel has progressed. By forming at least one of these two layers (bonding layer and covering layer), the state of the asbestos-containing layer is further modified (secondary modification).

  The particle size of the silica sol used in the treatment agent of the present invention is preferably 5 nm to 100 nm. In the treatment agent, when the particle size of the silica sol is 100 nm or less, a function of uniformly penetrating the fine structure of the asbestos fibers of the asbestos-containing layer can be achieved. If the particle size of the silica sol exceeds 100 nm, the penetration of the asbestos fibers in the asbestos-containing layer to the fine portions of the asbestos fibers may not be achieved, and the fiber binding ability to join the asbestos fibers may not be obtained. Moreover, since the silica sol whose particle diameter is less than 5 nm is expensive, there is a possibility that it lacks practicality as a silica sol added to the treatment agent in consideration of the cost and the amount used. Thus, in the present invention, in order to obtain a fiber binding ability that penetrates into the asbestos-containing layer and joins the asbestos fibers, it is preferable to use a silica sol having a particle diameter of 5 nm to 100 nm.

  The silica sol is dispersed in the solvent so that the content of the silica sol contained in the colloidal dispersion forming the treatment agent is 1% by weight to 20% by weight. If the content of the silica sol is less than 1% by weight, there is a possibility that the treating agent has insufficient fiber binding ability. If the silica sol content exceeds 20% by weight, the viscosity may increase. And as the content of silica sol increases, the viscosity gradually increases, and the decrease in permeability to the asbestos fiber layer, in which the content of silica sol exceeds 25% by weight, becomes remarkable. Thus, in order to optimize the permeability of the treatment agent to the asbestos fiber layer, the content of the silica sol is preferably in the range of 3% by weight to 20% by weight, and the permeability of the treatment agent is improved. In consideration of maintaining and allowing the treating agent to exhibit sufficient fiber binding ability, the content of the silica sol is more preferably 4% by weight to 15% by weight.

  The fiber binding ability in the present invention refers to the ability of the treatment agent attached to the asbestos fibers to join and bind the asbestos fibers to such an extent that the asbestos fibers can be prevented from scattering.

  The viscosity of the treatment agent of the present invention is such that the flow time by a 3 mm cup by the flow cup method is 30 seconds or less. Here, the flow cup method is a viscosity measuring method defined in JIS K 5600-2-2. In this viscosity measurement method, the temperature of the test solution is set to 23 ° C., a receiving container is placed under the flow cup, the orifice of the flow cup is pressed with a finger, the test solution is poured into the flow cup, and the finger is separated from the orifice. The test liquid is allowed to flow down, and the time from the moment when the test liquid starts to flow down from the orifice to the moment when the flow first breaks is measured as the flow down time.

  The treatment agent of the present invention belongs to a viscosity in which the flow time by the flow cup method is 10 seconds to 30 seconds, or a viscosity that is a numerical value lower than that. The viscosity at which the flow-down time is 10 seconds to 30 seconds is equivalent to that of fresh water.

  A surfactant may be added to the treatment agent of the present invention. By adding a surfactant to the treatment agent, the surface tension, that is, the wettability can be adjusted together with the adjustment of the viscosity of the treatment agent of the present invention.

  Examples of the surfactant added to the treatment agent include nonionic surfactants and anionic surfactants.

  Nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene-polyoxypropylene glycol, fatty acid sorbitan ester, alkyl polyglucoside, fatty acid diethanolamide, alkyl monoglyceryl ether, and the like. .

  Anionic surfactants include monoalkyl sulfate, alkyl polyoxyethylene sulfate, polyoxyethylene alkyl ether sulfate, alkylbenzene sulfonate, alkyl naphthalene sulfonate, alkyl sulfonate, α-olefin sulfonate And monoalkyl phosphates.

  The addition amount of the surfactant added to the treatment agent is such that the addition amount of the surfactant is 0.01 wt% to 0.10 wt%, and 0.01 wt% to 0.05 wt%. Is preferable, and it is more preferable that it is 0.01 to 0.03 weight%. If the amount exceeds 0.10% by weight, the foaming phenomenon becomes significant as it hinders spraying construction.

  When 0.01% by weight to 0.10% by weight of a surfactant is added to the treatment agent of the present invention, the treatment agent exhibits a viscosity of 8 seconds to 22 seconds when the flow-down method is 8 seconds. This viscosity shows a low viscosity of about half or less from a range substantially equivalent to the viscosity of fresh water (flowing time by the flow cup method at 23 ° C. is 20.4 seconds). In order to make use of the characteristics of the treatment agent of the present invention, a solution having a viscosity of 5 to 30 seconds for the flow time by the flow cup method is preferred.

  The method for preventing asbestos fiber scattering of the present invention is a containment process of an asbestos-containing layer using the treatment agent of the present invention. That, asbestos fiber scattering prevention method, the treating agent of the present invention is sprayed on asbestos construction surface, causes wet the asbestos fibers by the treatment agent, and impregnated with the treatment agent to the asbestos-containing layer bonded asbestos fibers mutual It is what you do.

  In carrying out the method for preventing asbestos fiber scattering of the present invention, the work space is cured with a sheet except for the asbestos construction surface in order to prevent asbestos from scattering from the work site to the outside. A clean room is installed at the entrance and exit of the work site, and the work site enters and exits through the clean room. Curing such a work space with a sheet and installing a clean room are similarly performed in the case of the asbestos-containing layer removal process described later.

  When spraying the treatment agent on the asbestos construction surface during the construction of the asbestos-containing layer using the treatment agent, the treatment agent is sprayed in the form of a thick mist in the work space in advance to wet the scattered asbestos fibers. It is preferable to make the asbestos fibers non-scattered.

  In the construction of the containment or removal treatment of the asbestos-containing layer using the treatment agent of the present invention, the conditions of the viscosity and surface tension of the treatment agent sprayed on the work space, as the spray condition, the condition of the asbestos-containing layer or the work space Conditions suitable for the above are selected widely.

  As for the spraying conditions, when an operation for spraying and retaining the processing liquid in the form of concentrated mist droplets is performed, a spray gun and a compressor are preferably used for realizing the operation. In that case, the nozzle diameter of the spray gun is preferably 0.7 mmφ to 1.2 mmφ, and the pressure of the compressor is preferably carried out at a low pressure of 0.1 Mpa to 1.0 Mpa.

  When the treatment liquid is sprayed on the work space under the above-described conditions, a dense mist-like droplet having a particle diameter of 10 to 100 μm is formed by the spray, and the droplet floats in the work space and settles soon. The droplets in the floating or sinking state come into contact with the floating asbestos fibers. At this time, the asbestos fibers are absorbed by the droplets having improved wettability, and the dust is formed by the natural sedimentation of the droplets. When the asbestos fibers are absorbed by the droplets, the mass of the droplets becomes heavier at the same time, so that dusting can be reliably achieved. The asbestos fibers contained in the dust droplets form a fiber bundle after drying, and are stably modified to a non-scattering state. In addition, when the sprayed droplet adheres to the asbestos-containing layer, the asbestos of the adhering portion is wetted, and the surface of the asbestos-containing layer is also stably modified to a non-scattering state.

  In the asbestos fiber scattering prevention method of the present invention, an operation of spraying the treatment agent on the asbestos construction surface by high-pressure injection is performed. For realizing this work, a spray gun and a compressor are preferably used. In that case, the nozzle diameter of the spray gun is preferably 1.2 mmφ to 2 mmφ, and the pressure of the compressor is preferably 0.4 Mpa to 4.0 Mpa. The discharge amount of the nozzle is preferably 0.4 L / min to 4.0 L / min. In order to perform this operation, an airless spray for general painting may be used.

  According to the asbestos fiber scattering prevention method of the present invention, the asbestos-containing layer is fixed and the asbestos fiber is reliably prevented from scattering because the treatment agent penetrates into the asbestos-containing layer to join the asbestos fibers to each other. Can do. Therefore, by this asbestos fiber scattering prevention method, exposure of asbestos fibers can be prevented, a safe environment can be established, and health problems caused by asbestos can be solved.

  The asbestos fiber scattering inhibitor of the present invention can be used for carrying out the asbestos-containing layer removing method. Here, the asbestos-containing layer removal method is a removal process of the asbestos-containing layer using this treating agent. That is, the treating agent of the present invention by blowing the high-pressure injection asbestos construction surface, wet the asbestos fibers by the treatment agent, asbestos-containing by which infiltrated the treatment agent to asbestos-containing layer bonded asbestos fibers mutual The layer is peeled off from the asbestos construction surface.

  When the treatment agent is sprayed onto the asbestos construction surface during the asbestos-containing layer removal treatment using the treatment agent, the treatment agent is sprayed in the form of a thick mist in the work space in advance to wet the scattered asbestos fibers. It is preferable to make the asbestos fibers non-scattered. The nozzle diameter of the spray gun used for the spraying operation and the pressure of the compressor are the same as in the case of the spraying process described in the explanation of the asbestos fiber scattering prevention method.

  According to the above asbestos-containing layer removal method, the asbestos-containing layer is peeled off in a wet state and in a fiber-bound state, so that the asbestos fiber does not scatter during peeling, and there is no danger that the worker is exposed to asbestos fibers. Absent. Similarly, when the separated asbestos fiber lump falls to the floor surface, the asbestos fiber does not scatter and is safe in operation. And since the asbestos fiber lump which peeled off from the asbestos construction surface and deposited on the floor is removed in a wet state, the asbestos fibers do not scatter during the removal operation, and it is safe. After the treatment agent is dried, the asbestos is three-dimensionally coated and fixed with a hard coating, so that the disposal process can be performed safely.

  In carrying out the asbestos fiber scattering prevention method and the asbestos-containing layer removal method, the treatment agent of the present invention is adjusted to pH 9-11.

  In the asbestos fiber scattering prevention method and the asbestos-containing layer removal method, the asbestos construction surface is the surface of the asbestos-containing layer formed on the predetermined object or the boards containing asbestos attached to the predetermined object. A face can be mentioned. Here, examples of the predetermined object include an architectural frame and an object that may be formed into a layer structure including asbestos, such as an electric product and an automobile. In the case where the object is an architectural enclosure, the asbestos-containing layer is formed by spraying and painting a material composition containing asbestos on a predetermined part (ceiling, wall surface, etc.) of the building enclosure. Moreover, boards containing asbestos are obtained by molding a material composition containing asbestos.

  Next, a mechanism (fiber binding mechanism) in which asbestos fibers contained in the asbestos-containing layer are bound by the treatment agent of the present invention will be described.

  FIG. 1A to FIG. 1C are schematic views illustrating a fiber bundling mechanism of an asbestos-containing layer. The schematic diagram is an example in which the asbestos-containing layer is a layer containing asbestos fibers in cement.

  In FIG. 1 (A), 1a and 1b show asbestos fibers. The length of the asbestos fibers 1a and 1b is generally 5 μm to 20 μm. When the treatment agent 2 of the present invention is supplied to the asbestos fibers 1a and 1b, as shown in FIG. 1B, the surface of the asbestos fibers 1a and 1b and the periphery thereof have a colloid dispersion liquid forming the treatment agent 2. Since it has excellent osmotic power, it is easily wetted. At the same time, a sticky gel is generated by reaction with the alkaline earth metal ions derived from cement contained in the asbestos fibers 1a and 1b, and the asbestos fibers 1a and 1b are covered. Thus, the mass is increased and the primary reforming is achieved.

  After the treatment agent 2 reacts with the alkaline earth metal ions and changes to a gel, the gel changes to a dry gel by air drying. And as shown in FIG.1 (C), the coating layer 3 by a vitreous thin film or a pozzolanic reaction product is formed with the change which goes to a dry gel. In this way, secondary reforming is achieved. At this time, asbestos fibers are bound in the coating layer 3.

  Thus, the asbestos fibers 1a and 1b are joined to each other by the treatment agent 2, so that the asbestos fibers cannot be released alone, and the asbestos fibers are prevented from being scattered around.

  2 (A) and 2 (B) show phase contrast micrographs (5000 times magnification) showing the state of asbestos fibers before and after treatment with the treating agent, and FIG. 2 (A) shows asbestos fibers before treatment. FIG. 2 (B) shows the state of asbestos fibers after treatment. According to FIG. 2 (B), a state in which a plurality of asbestos fibers are bound by the treatment agent and a uniform coating layer is formed on the surface thereof is observed.

  As can be understood from the description using the schematic diagrams of FIGS. 1 (A) to 1 (C), the asbestos-containing layer has a layer structure composed of asbestos fibers, and is formed on the surface of the asbestos fibers. Asbestos fibers are joined together by a treatment agent that has penetrated up to the gap between the asbestos fibers (penetrated to the gap between the asbestos fibers) to form a fiber bundle formed into a three-dimensional filter.

  The appearance of this fiber bundle is shown in FIG. 3 (A) and 3 (B) show scanning electron micrographs (500 times magnification) showing the state of the asbestos fiber layer before and after treatment with the treatment agent. FIG. 3 (A) shows the state before treatment. The state is shown, and FIG. 3B shows the state after processing. According to FIG. 3 (B), the treatment agent that has permeated the surface of the asbestos fiber covers the asbestos fiber, and the asbestos fiber forming the asbestos-containing layer is bound by the coating formed by drying the treatment agent. Show.

  As described above, the asbestos-containing layer is wetted or coated with the treatment agent of the present invention over the entire surface and inside, and a coating is formed on the entire asbestos fibers by binding of the treatment agent to form a bundle. Moreover, the treatment agent of the present invention has a low viscosity (approximately the same as or lower than the viscosity of fresh water) and is excellent in permeability.

  Specifically, for example, when an asbestos-containing layer is formed on the surface of a building frame formed using cement, the asbestos fiber scattering prevention treatment method and the asbestos-containing layer removal treatment method of the present invention are implemented. order to, when performing spray application of processing agent to asbestos construction surface is the surface of the asbestos-containing layer, the treatment agent of the present invention is reached building structures in asbestos construction surface (permeate), whereby the asbestos-containing Strengthening of the connection between the strata and the building frame. Therefore, the treatment agent of the present invention achieves the binding of asbestos fibers and the strengthening of the bonding between the asbestos-containing layer and the building frame.

  As described above, the asbestos-containing layer is bound by spraying the asbestos-containing layer using the treatment agent of the present invention, so that the asbestos fibers can be reliably prevented from scattering. Therefore, it becomes possible to prevent the worker from being exposed to the scattered asbestos fibers during the containment treatment and the removal treatment using the treatment agent of the present invention, and to provide a safe working environment. It becomes possible to solve the problem of health damage caused by

  Ethanol may be added to the treatment agent of the present invention. Moreover, the treatment agent to which ethanol is added may be used for the asbestos fiber scattering prevention method and the asbestos-containing layer removal method.

  Such a treatment agent can be obtained as an ethanol dilution of a colloidal dispersion obtained by further adding ethanol to a colloidal dispersion obtained by dispersing silica sol in water.

  In the treatment agent, ethanol has a function as a freezing temperature adjusting agent, and in particular, functions as a freezing inhibitor. When the treatment agent is a dispersion (30% diluted solution) prepared by adding ethanol to a colloidal dispersion to contain 30% by weight of ethanol, the freezing temperature of the treatment agent is 21.0 ° C. below zero. . When the treatment agent is a dispersion (50% diluted solution) prepared by adding ethanol to the colloidal dispersion to contain 50% by weight of ethanol, the freezing temperature of the treatment agent is 38.0 ° C. below zero. . In either case, the treatment agent to which ethanol has been added exhibits a very low freezing temperature. The amount of ethanol added is appropriately selected according to the required low freezing temperature, but the amount of ethanol added should be 50% by weight or less from the viewpoint of safety, cost and practical use. Preferably, it is 10 to 20% by weight. In addition, the ethanol dilution liquid is a highly safe liquid for the human body, can be mixed with the treatment agent of the present invention in a free range, and the treatment agent's function to prevent the asbestos fibers from scattering is also hindered. Even from the viewpoint of the low possibility of exertion, ethanol is suitable as the freezing temperature adjusting agent of the treatment agent of the present invention.

  The treatment agent of the present invention may be one to which a fluorescent pigment is added (luminescent treatment agent).

  The luminescent treatment agent is formed by adding and mixing a fluorescent pigment to the colloidal dispersion forming the treatment agent. There are two types of fluorescent pigments: inorganic fluorescent pigments and organic fluorescent pigments. Furthermore, it can classify | categorize into an aqueous pigment and a solvent-type pigment in each kind. Both inorganic pigments and organic pigments can be applied to the light emission treating agent of the present invention. As the light-emitting treatment agent, a pigment-dispersed fluorescent pigment is preferably used. The addition amount of the fluorescent pigment in the light-emitting treatment agent is in the range of 0.01% by weight to 1.00% by weight with respect to the weight of the treatment agent other than the fluorescent pigment, from the viewpoint of sufficiently obtaining the light emission luminance by irradiation with black light. Yes, 0.20 wt% to 1.00 wt% is preferable, and 0.30 wt% to 0.80 wt% is more preferable.

  After carrying out spraying using the light-emitting treatment agent of the present invention on the asbestos-containing layer, the specific fluorescent color derived from the fluorescent pigment of the light-emitting treatment agent by irradiating the site where the work was carried out with black light Is emitted. Even if it is irradiated with black light, a fluorescent color derived from the fluorescent pigment of the light-emitting treatment agent does not occur in the unexecuted site around the site where the application was performed. Thereby, it is possible to visually confirm in which range the spraying construction was carried out, the progress of the work of the asbestos fiber scattering prevention process and the asbestos-containing layer removal process, or the achievement rate of those work, This can be easily confirmed by observation of the emission luminance.

  As the black light, high-intensity portable UV 14 LED black lights using 14 UV-LED lamps are preferably used in that light emission can be confirmed clearly even from a relatively remote place.

Example 1
A colloidal dispersion (hereinafter referred to as “silica sol”) having a silica sol content adjusted to 30 wt% by dispersing silica sol (average particle size of 10 to 20 nm) (manufactured by Nissan Chemical Industries, Ltd., Snowtex-30) in a solvent (water). , Dispersion A).

  The viscosity of the colloidal dispersion (dispersion A) was measured. The viscosity was measured as the value of the flow-down time using a flow cup having an orifice diameter of 3 mm with the temperature of the test solution set to 23 ° C. by the flow cup method defined in JIS K 5600-2-2. The results are shown in Table 1.

Example 2
A colloidal dispersion (hereinafter referred to as dispersion B) was prepared in the same manner as in Example 1 except that the content of silica sol was 15% by weight. The viscosity of the colloidal dispersion (dispersion B) was measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1
The viscosity was measured in the same manner as in Example 1 except that fresh water was used instead of the colloidal dispersion. The results are shown in Table 1.

  As a result of the viscosity measurement in Examples 1 and 2 and Comparative Example 1, the flowing times of Dispersion A, Dispersion B, and fresh water were 35.2 seconds, 20.8 seconds, and 20.4 seconds, respectively. According to the results of these viscosity measurements, Dispersion A exhibits a higher viscosity than that of clear water, but Dispersion B exhibits a viscosity equivalent to that of clear water, and Example 2 is a treatment liquid having an extremely low viscosity. More preferable as a treating agent.

Examples 3 and 4
In Examples 3 and 4, colloidal dispersions (hereinafter referred to as Liquid B-01 and Liquid B-05, respectively) were obtained in the same manner as in Example 1 except that the content of silica sol was 1 wt% and 5 wt%, respectively. ) Was prepared.

  The viscosity of each colloidal dispersion (Liquid B-01 (Example 3), Liquid B-05 (Example 4)) was measured in the same manner as in Example 1. The results are shown in Table 1.

Example 5
(Adjustment of specimen)
Based on the Ministry of Land, Infrastructure, Transport and Tourism Notification No. 1168, a construction material (hereinafter referred to as a pseudo asbestos layer forming material) having a layer that simulates an asbestos-containing layer (hereinafter referred to as a pseudo asbestos layer forming material) was created, and this pseudo asbestos layer forming material was used as a test specimen. .

  The composition of the pseudo asbestos layer is composed of 35% by weight of rock wool, 15% by weight of Portland cement and 50% by weight of water.

(Penetration experiment)
The treatment agent of the present invention (dispersion B) prepared in Example 2 was sprayed onto the pseudo asbestos layer of the test specimen to conduct a penetration experiment. In the penetration experiment, spraying of the treatment agent on the test specimen was performed in two steps. Airless spray was used for spraying the treatment agent.

(Spraying treatment agent)
The first spraying and the second spraying were performed at 15 minute intervals. The amount of the treatment agent sprayed in the first spraying was 1.0 kg / m ^2, and the treatment agent equivalent to 2.8 kg / m ² was sprayed in two times. In the experiment of penetration of the treatment agent into the pseudo asbestos layer, the surface treatment of the treatment agent was slightly the same as the first spray treatment and the second spray treatment at the same time as the finish of the spray treatment. In the extent to which the gray became darker, the rapid permeability of the treatment agent was confirmed.

Examples 6-8
Example 5 except that Dispersion A (Example 6), Liquid B-01 (Example 7), and Liquid B-05 (Example 8) were used instead of Dispersion B of the treatment agent of the present invention. Similarly, penetration experiments were performed.

  The permeation experiment in Example 6 using the dispersion A as the processing liquid, is first spray treatment observation short gloss by the liquid reservoir to the spray surface at, at the second spraying process shiny by liquid pool About 3 minutes were observed. Compared to the dispersion B, a slow permeability was observed.

  In the penetration experiments in Examples 7 and 8 using the liquid B-01 and the liquid B-05 as the treatment liquid, both the liquid B-01 and the liquid B-05 were sprayed for the first time as in the case of the dispersion B. The treatment liquid was quickly absorbed into the pseudo asbestos layer together with the second spraying treatment, and suitable permeability was confirmed.

Examples 9-12
In Examples 9 to 12, the dispersion A (Example 9), the dispersion B (Example 10), the liquid B-01 (Example 11), and the liquid B-05 (implementation) in ascending order of the example numbers, respectively. Using Example 12) as a treating agent, each specimen was sprayed with a treating agent. Adjustment of the test body and spraying of the treatment agent were carried out in the same manner as in Example 5.

  Using spray after application of the test bodies obtained in each of Examples 9-12, the measurement of the adhesion strength and the breaking depth of the test body in compliance with the measurement method of building materials of Land, Infrastructure and Transport Notification No. 1168 No. went. The results are shown in Table 2.

Bond strength test (according to Ministry of Land, Infrastructure, Transport and Tourism Notification No. 1168):
A 10 cm square steel plate is adhered to the vicinity of the center of the test body with a solvent-free two-component epoxy adhesive, and a weight of 1 kg is placed thereon and left to stand for 24 hours. After that, the steel sheet was cut up to 20 mm along the periphery of the steel plate, and the tensile stress was applied at a rate of 1 mm per minute in the vertical direction of the test surface to measure the breaking stress when the pseudo asbestos layer of the test specimen was broken. The adhesion strength (N / cm ² ) was determined. Moreover, as the rupture depth, the rupture depth when the pseudo asbestos layer was ruptured during the measurement of the adhesion strength was measured.

Comparative Example 2
Measure the adhesion strength and fracture depth of the test specimens in the same manner as in Examples 9 to 12 except that the specimens that were not sprayed were used instead of the specimens after spraying. It was. The results are shown in Table 2.

  From the results shown in Table 2, the adhesion strength of the pseudo asbestos layer was improved in the test body using the dispersion B as a treatment agent. In addition, the fracture depth of the test specimens using the liquid B-05 and the dispersion B as the treatment agent was improved, and it was confirmed that the fracture depth was improved as the concentration of the silica sol of the treatment agent was increased. In the present invention, it has been confirmed that when the treatment agent has a composition forming the dispersion B, the solidification treatment of the pseudo asbestos layer is more suitably achieved.

Example 13
Changes in the surface tension of the treatment agent were measured. The measurement method uses a method (pendant drop method) in which a sample solution is injected into an automatic burette, a fixed amount of sample solution is dropped from the tip of the sample into a watch glass, and the weight is precisely weighed with an analytical balance. It was. As the sample solution, the treatment agent (dispersion B) prepared in Example 2 was used. As a result of the measurement, the weight of the droplet when the dispersion liquid B was used as the sample liquid was 6.0 g.

Comparative Example 3
The change in the surface tension of the sample solution was measured in the same manner as in Example 13 except that clear water was used as the sample solution instead of the dispersion B. As a result of the measurement, the droplet weight was 5.80 g.

  Thus, as a result of the measurement in Example 13 and Comparative Example 3, the droplet weights of fresh water and dispersion B were 5.80 g and 6.0 g, respectively, and dispersion B was about 3% compared to fresh water. High drop weight was shown. This indicates that the dispersion B has a slightly higher surface tension than that of fresh water.

Example 14
When the treatment agent was constituted by adding a surfactant to the colloidal dispersion, the change in the surface tension of the treatment agent was measured. As the colloidal dispersion, the dispersion B prepared in Example 2 was used.

  A treatment agent in which 0.01% by weight, 0.02, 0.03, 0.04, 0.05, 0.06% by weight of a surfactant (manufactured by Kao Corporation, Emulgen 707) is added to dispersion B. (The liquid B14-1, the liquid B14-2, the liquid B14-3, the liquid B14-4, the liquid B14-5, and the liquid B14-6 are prepared in order from the smallest addition amount of the surfactant.) Using the treatment agent as the sample solution, the change in surface tension was measured by the same pendant drop method as in Example 13, and the effect of adding the surfactant was evaluated by the weight of the droplet. The measurement results are shown in FIG. For convenience, the numerical value of the addition amount shown in the graph of FIG. 4 is a positive number obtained by multiplying the actual addition amount by 100 times. Moreover, the data shown by the plot of the position of N% in the graph of FIG. 4 respond | corresponds to the data in case a processing agent is the liquid B14-N (N is an integer of 1-6).

  When 0.01% by weight of surfactant was added to Dispersion B (Liquid B14-1), the droplet weight was 4.6 g, which was slightly lower than that of fresh water. Further, as the amount of the surfactant added increases, the droplet weight gradually decreases. When 0.03 wt% of the surfactant is added to the dispersion B (liquid B14-3), the droplet weight is It was 3.2 g, which was about 44% less than the droplet weight of fresh water. This means that when 0.03% by weight of the surfactant is added to the dispersion B, the surface tension is reduced by about 50% compared to that of fresh water. This indicates that the adjustment range of the liquid property of the treatment agent is wide. In addition, when the addition amount of the surfactant is 0.03% by weight or more (Liquid B14-3, Liquid B14-4, Liquid B14-5, Liquid B14-6), foaming occurs as the addition amount of the surfactant increases. It became remarkable at 0.05 weight% or more. In consideration of the above results, a more preferable range of addition of the surfactant is about 0.01 to 0.03% by weight.

Example 15
Dispersion B was used as a treating agent, and the spraying of the treating agent was performed on each test specimen. Adjustment of the test body and spraying of the treatment agent were carried out in the same manner as in Example 5. However, three test specimens were prepared, and each was sprayed with a treatment agent.

  The air erosion test was done using the test body after spray construction. The air erosion test was conducted by a method for measuring building materials based on Ministry of Land, Infrastructure, Transport and Tourism Notification No. 1168. The results are shown in Table 3.

Air erosion test (conforms to MLIT Notification No. 1168):
(Wet and dry repeated treatment)
The process of leaving the test specimen in an environment of 60 ° C. ± 3 ° C. and relative humidity 95% ± 5% for 16 hours and immediately drying in an environment of 60 ° C. ± 3 ° C. for 8 hours was repeated 10 times. An air erosion test was carried out for those subjected to such wet and dry repeated treatments and those not subjected to such treatments.

(Air erosion test)
The air erosion test was performed by the following method. That is, a test body is installed in an air ejection device equipped with a nozzle having a diffusion angle of 90 degrees, air with a pressure difference of 98 Kpa is blown from the nozzle, and air is uniformly blown to the test body from a position 15 cm away from the nozzle. Air was collected with a membrane filter having a diameter of 25 mm at a rate of 1.5 liters per minute for 60 minutes, and the number of fibers in the collected air was measured by a measuring method of JIS K 3850-1 using a phase contrast microscope. . The results are shown in Table 3.

  In the result of the air erosion test, if the number of collected fibers is 10 or less, it is determined that the processing liquid has been confirmed to have a function of preventing asbestos fibers from being contained. According to the results shown in Table 3, each of the test bodies 1, 2, and 3 sprayed with the dispersion B forming the treatment agent of the present invention has a number of collected fibers of 10 or less. It is judged that it functions as an asbestos fiber scattering prevention treatment agent.

  Moreover, as shown in Table 2, the test body sprayed with the dispersion B as the treatment agent of the present invention has high adhesion strength. This means that the fibers of the test specimen are joined and bound by the dispersion B. Moreover, the test body sprayed with the dispersion B also has a large numerical value of the breaking depth. The fact that the numerical value of the breaking depth is large confirms that the fibers are bound from the surface layer portion of the fiber layer to the depth. Such an air erosion test and an adhesion strength test prove that the dispersion B has a quality performance suitable for the asbestos scattering inhibitor of the present invention.

Example 16
A mixed solution obtained by stirring 10 g of Portland cement powder in 50 mL of fresh water was allowed to stand for 10 minutes to obtain 5 mL of supernatant water of the mixed solution, and this supernatant water was added to 100 mL of dispersion B and stirred to obtain a stirring solution.

  As the stirring liquid became more homogenized by stirring, the entire stirring liquid became thick and cloudy, and at the same time the viscosity increased rapidly. After the stirring of the stirring liquid was stopped, the stirring liquid was observed from the side of the beaker. In the stirring liquid, generation of countless translucent granular materials was observed, and it was confirmed that the components contained in the supernatant water and the components of the dispersion B reacted to generate a reactive organism. Although the said liquid was made into the sample liquid and implementation of the viscosity measurement based on the flow cup method of Example 1 was tried, the sample liquid did not flow down from an orifice. Moreover, although the said liquid was tried for the measurement of surface tension by implementation of the pendant drop method of Example 3 as a sample liquid, it did not flow down also from an automatic burette. From the results of these experiments, it was confirmed that the supernatant water and the dispersion B reacted by mixing to form a highly viscous hydrated product as a reaction product.

  However, Portland cement powder The mixture was stirred in a 10g Shimizu 50 mL, typically, the alkaline earth metal ions derived from the material composition constituting the cement to form a Boards containing asbestos-containing layer and asbestos, And alkaline earth metal ions derived from asbestos. The supernatant of the mixed solution also contains alkaline earth metal ions. Therefore, the result of this Example shows that the dispersion B reacts with the cement and asbestos-derived alkaline earth metal ions contained in the asbestos-containing layer to form a highly viscous hydrated product as a reaction product. .

Example 17
Twenty specimens (small asbestos) were collected (sorted) from the asbestos-containing layer of the existing concrete structure formed by spraying the asbestos-containing layer, and these were used as samples. A treatment agent was attached to these samples to form test pieces, and a moisture retention function test (asbestos-containing layer wetting maintenance test) was performed using the test pieces. Dispersion B obtained in Example 2 was used as the treatment agent.

(Moisturizing function test)
Of the 20 sampled samples, 10 were selected as sample 1 and the remaining 10 as sample 2. Each of Sample 1 and Sample 2 was left in the room for 10 days and air-dried, and then the weight of each was measured to determine the average weight. The results are as follows.

Average weight of sample 1 (average weight of 10 asbestos bunches): 5.3 g
Average weight of sample 2 (average weight of 10 asbestos lumps): 6.2 g

  Dispersion B was allowed to stand overnight the sample 1 was put into a beaker poured (1000 ml) (solution temperature 23 ° C.), thoroughly After confirming that the water-saturated, the sample was taken out 1, is dropped in a stationary state waterdrop Then, the excess water was removed by leaving it on the filter paper for 5 hours, and individual weights were measured with an analytical balance to obtain an average weight.

  Using the average weight at this time as a reference value, the time-dependent change in weight due to air drying was measured. That is, when the average weight at this time was set to “100 wt%”, it was measured what kind of weight reduction was exhibited by subsequent drying over time. As a measuring method, the sample was left in the room, and the weight of the sample was measured every day at 10 o'clock to determine the average weight, and the degree of weight decrease over time was specified. The degree of weight loss was calculated as “weight loss%”. Weight loss% is in the case where the average weight of the sample at the start of measurement is 100% by weight values (W1) obtained by subtracting the mean weight at air drying, minus the mean weight at air drying from the average weight of each weight measurement point It is obtained as a relative value (Wt / W1 × 100) of the value (Wt). The results are shown in FIG.

  For comparison, using fresh water (1000 ml) adjusted to 23 ° C. instead of dispersion B, immersing sample 2 in the fresh water, causing water saturation as in the case of using sample 1, and further drying. Thereafter, the weight of each sample constituting Sample 2 was measured, and the average weight was obtained. And the average weight at this time was set to "100 weight%", and the weight reduction by subsequent drying over time was measured by the method similar to the case of the said sample 1. Weight loss was expressed in% weight loss. The results are shown in FIG.

  As shown in FIG. 5, Sample 2 wet-treated with fresh water had a large weight reduction rate due to drying, and reached the air dry weight 4 days after the start of measurement. On the other hand, Sample 1 wet-treated with Dispersion B had a slow weight reduction rate due to drying, and 14 days or more were required until the weight reduction tendency was stabilized, resulting in an increase in weight of 5.5%. This confirms that the sample 1 wet-treated with the dispersion B maintains a wet state for a long time and has a function of preventing asbestos fiber scattering. In sample 1, it is presumed that the product resulting from the reaction between dispersion B and alkaline earth metal ions adheres to the surface layer of asbestos fibers, and a film covering asbestos fibers is formed.

Example 18
A confirmation test was carried out to prevent the exposure of scattering asbestos by spraying treatment agents.

  Confirmation test is performed as a pretreatment in the practice of containment construction asbestos-containing layer which is applied to the refractory coating material, which is installed on the ceiling portion of the existing buildings, are scattered around the asbestos-containing layer This was done by measuring whether exposure by asbestos fibers was prevented.

  In spraying the treatment agent, AKImist “D” manufactured by Ikeuchi Co., Ltd. was used as a sprayer. Dispersion B was used as the treating agent. The spraying was performed by spraying 2.5 L of the dispersion B toward the ceiling by an operation for 30 minutes. In addition, the room which has the ceiling part made into spray object is a space whose floor area is 7.2 m x 5.4 m and height is 2.7 m. According to the official working environment measurement method, before spraying the treatment agent, the indoor asbestos dust concentration was measured and found to be 15 in 1 L of space. After the treatment agent was sprayed for 2 hours, the indoor asbestos dust concentration was measured. As a result, less than 0.3 measurement results were obtained in 1 L of space. Indoor asbestos dust concentrations were measured during and after the containment work. Even in the measurement of the asbestos dust concentration in the room during and after the containment work, the measurement result was less than 0.3 in 1 L of space. This indicates that dust dispersion by spraying of the dispersion liquid B has been achieved, and results have been obtained in which safety is ensured against exposure damage to workers or environmental pollution.

Examples 19-20
(Adjustment of antifreeze treatment)
Ethanol was added as a freezing temperature adjusting agent to the dispersion B prepared in Example 2 to prepare a treating agent (freezing resistant treating agent).

  The antifreezing treatment agents of Examples 19 to 20 were adjusted so that the ethanol concentration in the antifreezing treatment agent was 10% by weight (Example 19) and 20% by weight (Example 20). .

  Using each of the obtained antifreezing treatment agents, a freezing test was performed.

(Freezing test)
Using a freeze-resistant treatment agent as a test solution, a beaker containing 100 mL of the test solution was placed in a freezing and thawing tester, cooled to a predetermined temperature, and held in that state for 5 hours. Thereafter, the test solution is taken out of the freeze-thaw tester and the test solution immediately after removal (test solution in state 1) and the test solution taken out to room temperature (23 ° C.) (test solution in state 2). Further, the viscosity of the test solutions in states 1 and 2 was measured. Viscosity measurement using a flow cup described in Example 1 was used for viscosity measurement.

  The cooling temperature of the test solution was set to a temperature within this range by setting the internal temperature of the freeze-thaw tester in a range from 4.0 ° C. below zero to 20.0 ° C. below zero.

(Test liquid state observation)
It was confirmed that the antifreezing treatment agent of Example 19 (ethanol addition amount 10.0% by weight) was adjusted to be in an unfrozen state at 4.0 ° C. or higher below zero. The test solution added with 10.0% by weight of ethanol was frozen when the internal temperature was 10.0 ° C. below zero, and a slight suspended matter was confirmed in the solution after thawing in the room. Therefore, it was confirmed that the freeze-resistant treatment agent of Example 19 (ethanol addition amount 10.0% by weight) is an effective freeze-resistant treatment agent at a temperature higher than 10.0 ° C. under zero.

  It was confirmed that the antifreeze treatment agent of Example 20 (ethanol addition amount 20.0% by weight) was adjusted to be in an unfrozen state at 10.0 ° C. or higher below zero. Therefore, it was confirmed that the freezing-resistant treatment agent of Example 20 (ethanol addition amount 10.0% by weight) is an effective freezing-resistant treatment agent even at 10.0 ° C. below zero.

  Viscosity was measured using the freezing treatment agents of Example 19 and Example 20. The viscosity was measured as the value of the flow time using the flow cup method in the same manner as in Example 1.

  In Example 19, the flow-down time was 20.6 seconds, and in Example 20, the flow-down time was 20.3 seconds. As the amount of ethanol added to the antifreeze treatment agent increased, the viscosity of the treatment agent decreased. Indicated. This supports that ethanol is suitable as a substance added to the treatment agent.

Example 21
(Adjustment of luminescent treatment agent)
A fluorescent pigment was added to the dispersion B prepared in Example 2 to prepare a treatment agent (luminescent treatment agent). Among fluorescent pigments having a light emitting property, a dispersion type fluorescent pigment (Shinloi Color SW-10, manufactured by Shinroihi Co., Ltd.) out of two types of pigments, powder and dispersion, was prepared. Luminescent treatment agents (luminescent treatment agents 1 to 5) were prepared by adding the prepared fluorescent pigment to dispersion B. For each of the luminescent treatment agents 1 to 5, the addition amount of the fluorescent pigment is 0.01% by weight (the luminescent treatment agent 1) and 0.05% by weight (the luminescent treatment agent 2) with respect to the total weight of the luminescent treatment agent. ), 0.2 wt% (light emitting treatment agent 3), 0.5 wt% (light emitting treatment agent 4), and 1.00 wt% (light emitting treatment agent 5).

  Using the luminescent treatment agents 1 to 5, a light emission function confirmation test was conducted.

(Light emission function confirmation test)
A test body having a pseudo asbestos layer was prepared in the same manner as in Example 5, and each of the luminescent treatment agents 1 to 5 was sprayed toward the pseudo asbestos layer (spraying process), and the object to be processed for each. (To-be-processed objects 1-5) were adjusted. And the area | region (spraying area | region) to which the spraying process in the to-be-processed object was performed was irradiated with black light, and the light emission luminance of the spraying area was compared about each to-be-processed object. Thereby, the existence and superiority of the light emitting function of the light-emitting treatment agent were confirmed.

An airless spray was used for spraying the treatment agent. Moreover, in the spraying process, when the spraying amount of the luminescent treatment agent on the surface of the test body is 0.05 kg / m ² (first pattern), the spraying amount of the luminescent processing agent on the surface of the test body is 2.0 kg. This was carried out for two patterns in the case of / m ² (second pattern). In addition, the amount of spraying in the first pattern is asbestos when “treatment performed assuming anti-exposure by floating asbestos fibers” is assumed as “pre-treatment of construction processing such as asbestos fiber scattering prevention processing”. The amount of the processing agent sprayed toward the content layer is assumed. The amount of spraying in the second pattern assumes the amount of spraying of the treating agent sprayed onto the asbestos-containing layer in order to wet the asbestos-containing layer when assuming the containment process of asbestos fibers.

  As a result of the light emission function confirmation test, all of the light-emitting treatment agents 1 to 5 show emission luminance, but the effect treatment agent 1 has a slightly unclear luminance, and the light emission treatment agents 2 to 5 are accompanied by the addition amount. The luminance was high and the luminance was clear (particularly, the luminescent treatment agents 3 to 5).

  Existence of luminescence brightness due to the luminescent treatment agents 1 to 5 was recognized for both the first pattern and the second pattern. Moreover, when the same light emission processing agents 1-5 were used and the brightness | luminance measured by the 1st pattern and the brightness | luminance measured by the 2nd pattern were compared, the brightness | luminance difference was not recognized visually.

Example 26
Colloidal dispersion (dispersion C) (dispersion C) in the same manner as dispersion B in Example 2 except that the silica sol has an average particle size of 80 to 120 nm (Snowtex-PS-M, manufactured by Nissan Chemical Industries, Ltd.) 15.0% by weight) was adjusted. The silica sol contained in the dispersion B has an average particle diameter of 10 to 20 nm (primary particles).

  Using the prepared dispersion C, a penetration test was performed. The penetration test was performed in the same manner as in Example 5. In the dispersion C, the surface of the pseudo asbestos layer sprayed from the first time, and the gloss of the dispersion C was confirmed on the surface of the pseudo asbestos layer, and it took about 5 minutes until the luster disappeared. In the second spraying, a liquid pool was observed on the surface of the pseudo asbestos layer, and when compared with the dispersion B, the permeability was slow.

Examples 27 and 28
Colloidal dispersion (dispersion D) (dispersion D) in the same manner as dispersion B of Example 2 except that the silica sol has an average particle size of 40 to 60 nm (silica sol-snowtex XL manufactured by Nissan Chemical Industries, Ltd.) 15.0% by weight) was adjusted (Example 27). Further, the colloidal dispersion (dispersion) was performed in the same manner as the dispersion B of Example 2 except that the silica sol had an average particle diameter of 100 nm (large particle diameter silica sol-Snowtex PS-S manufactured by Nissan Chemical Industries, Ltd.). Liquid E) (15.0% by weight) was prepared (Example 28). Using the dispersion D of Example 27 and the dispersion E of Example 28, a penetration test was performed to observe the permeability, and the viscosity was measured. The penetration test was carried out in the same manner as in Example 5, and the viscosity was measured by the flow cup method in the same manner as in Example 1. The results for Examples 27 and 28 are shown in Table 4. From the measurement results, the dispersion B of Example 2 has a lower viscosity than the dispersion D of Example 27 and the dispersion E of Example 28, and the dispersion B is a more preferred colloidal dispersion. It is confirmed.

  In the dispersion D of Example 27, gloss was generated in a part of the coated surface in the first application, and a gel coat was confirmed in a part of the asbestos layer in the second application. In the dispersion E of Example 28, gloss was generated on a part of the coated surface in both the first and second coatings, and a slow permeation effect was observed. Therefore, Dispersion B was more permeable than Dispersion DE. It was confirmed that the particle size of the silica sol is about the silica sol of the dispersion B of Example 2 from the viewpoint of the penetration property.

Examples 29-30
In Examples 29 to 30, spraying of the treatment agent was performed on the test specimen in the same manner as in Example 5, except that Dispersion D and Dispersion E were used as treatment agents in ascending order of Example numbers. The construction was performed, and the adhesion strength and fracture depth of the test specimen were measured in the same manner as in Example 9. The results are shown in Table 5.

Comparative Example 4
As a treating agent, instead of the dispersion B, a water-soluble alkali silicate-based anti-scattering treating agent (WG) distributed in the market is used, and the spraying amount for the test piece is 11 in total. The adhesion strength (N / cm ² ) (X1) and the breaking depth (mm) (Y1) were measured in the same manner as in Example 10 except that the pressure was 0.0 Kg / m ² . In accordance with this, the adhesion strength (X0) and the fracture depth (Y0) were also measured for the specimens to which WG was not applied. And the improvement degree of the adhesion strength and fracture | rupture depth by application | coating of WG (X1 / X0, Y1 / Y0, respectively) was calculated. The results are shown in Table 6. In Table 6, based on the results of Example 10 and Comparative Example 2, the improvement in adhesion strength and fracture depth for Dispersion B calculated in the same manner as in Comparative Example 4 are shown.

  In comparison between dispersion B and WG, although there was a difference of about 4 times in the set value of the lower limit of coating, an increase in strength equivalent to 120% was confirmed in both dispersion B and WG in the adhesion strength test. In terms of the breaking depth, the dispersion B shows “not applied” and “applied” shows a little over 200%, while the WG shows about 110%. This difference proves that the dispersion B penetrates deeper into the pseudo asbestos layer during application, and further has a favorable function of forming a homogeneous fiber bundling or solidified layer.

  The above description is merely an example of the embodiment of the present invention, and various modifications can be made within the scope of the claims.

The present invention is an asbestos treatment agent composed of silicon dioxide as a main ingredient and a composition that is safe for the human body and the environment, such as facilities where there are concerns about health problems of the surroundings and users due to floating asbestos. It is a new technology that can be modified into a safe facility and can be used promptly after treatment.
The treatment agent of the present invention is excellent in permeability to the asbestos-containing layer because the liquidity such as viscosity is adjusted, and further, since the spraying and spraying conditions can be adjusted in various ways, the degree of freedom in construction is expanded. The construction cost can be significantly reduced. In addition, by using the fluorescent treatment agent of the present invention, the progress and achievement of construction can be confirmed by a non-contact method, and reliable construction management becomes possible.
INDUSTRIAL APPLICABILITY According to the present invention, the present invention is useful for providing a new technology for modifying a building material dangerous for a society advocating a healthy, safe and secure society into a safe functional material.

1a Asbestos fiber 1b Asbestos fiber 2 Treatment agent 3 of the present invention Coating layer

Claims (8)

  Asbestos fiber scattering prevention treatment characterized in that it consists of a colloidal dispersion in which silica sol is dispersed in water and has the ability to bind asbestos fibers by adhering to asbestos fibers and reacting with alkaline earth metal ions. Agent.   The asbestos fiber scattering prevention treatment agent according to claim 1, wherein the particle diameter of the silica sol is 5 nm to 100 nm, and the content of the silica sol is 1.0 wt% to 20.0 wt%.   The colloidal dispersion liquid is an asbestos fiber scattering prevention treatment agent according to claim 1 or 2, wherein the flow-down method has a viscosity of 30 seconds or less.   The asbestos fiber scattering prevention processing agent in any one of Claim 1 to 3 formed by adding a nonionic surfactant or an anionic surfactant.   The treatment agent for preventing asbestos fiber scattering according to any one of claims 1 to 4, wherein ethanol is added.   The asbestos fiber scattering prevention treatment agent according to any one of claims 1 to 5, wherein a fluorescent pigment is added. The asbestos fiber scattering prevention treatment agent according to any one of claims 1 to 6 is sprayed on an asbestos construction surface, the asbestos fiber is wetted by the treatment agent, and the treatment agent is infiltrated into the asbestos-containing layer. A method for preventing asbestos fiber scattering, characterized in that they are joined together.
  When the asbestos fiber scattering prevention treatment agent according to any one of claims 1 to 6 is sprayed on the asbestos construction surface, the treatment agent is sprayed in a thick mist in the work space in advance to wet the scattered asbestos fibers. The method for preventing asbestos fiber scattering according to claim 7, wherein the asbestos fiber is in a non-scattered state.