JP2007254817A - Rust preventive material for lightweight aerated concrete panel reinforcing steel and rust prevention method for lightweight aerated concrete panel reinforcing steel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rust preventive material for an ALC panel reinforcing steel which is excellent in rust preventiveness, the adhesiveness to the reinforcing steel and an ALC panel base metal, film formability, quality stability and supply stability, and can yield the ALC panel of a high commodity value, and an efficient rust prevention method using the rust preventive material. <P>SOLUTION: The rust preventive material for the ALC panel reinforcing steel is composed of a solution mixture containing principal components consisting of inorganic raw materials, water, and a resin emulsion, and a resin powder of 165 to 190°C in softening point and other additives. The rust prevention method for the ALC panel reinforcing steel using the material is also provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a rust prevention material for reinforcing steel bars embedded in a lightweight cellular concrete panel (hereinafter referred to as an ALC panel) and a rust prevention method using this rust prevention material. More specifically, for ALC panel reinforced reinforcing bars that have excellent rust prevention, adhesion to reinforcing bars and panel base material, film formation, quality stability, and are easy to obtain and can provide high-commercial ALC panels. The present invention relates to a rust prevention material and an efficient rust prevention method using the rust prevention material.

  ALC panels with high utility value as building materials are prepared by mixing water into a mixture of calcareous materials such as cement and lime and siliceous materials such as silica sand and silica stone, and then aluminum metal powder and bubble stabilizer Etc., and the mixture is poured into a mold with a reinforced anti-corrosion reinforcing bar, foamed and cured, and the resulting semi-cured product is cut into a desired dimension with a piano wire. It is manufactured by steam curing at a high temperature and high pressure in a crepe and curing.

  However, since this ALC panel has a large porosity of around 70%, when various gases and liquids permeate, the embedded reinforcing steel bars are easily corroded. In order to eliminate the problem, it has been conventionally performed to rust-proof the surface of the reinforcing reinforcing bar with a rust-proof coating.

  That is, first, a hook-shaped reinforcing bar is made from a reinforcing bar material, and a plurality of hook-shaped reinforcing bars are hung by a plurality of hanging rods coated with a release agent and conveyed to a rust prevention process. Next, after immersing the hook-shaped reinforcing bars in a rust-proof tank filled with a rust-preventing material, the work of drying at a temperature of 50 to 100 ° C. is repeated once or several times to prevent the reinforcing reinforcing bars from being surfaced. A rust coating is formed.

  The reinforcing reinforcing bar with the anticorrosive coating film formed on the surface is placed in the mold while being suspended from the suspension rod, and then the raw material slurry for the ALC panel is injected into the mold. Then, after the foaming and curing of the raw slurry progresses and a semi-cured body is formed, the suspension rod is pulled out from the semi-cured body and cut to a predetermined size with a piano wire. As the mold release agent, an oil-based one is usually used in consideration of mold release properties with respect to the rust preventive material and the semi-cured material, ease of application of the mold release agent, and the like.

  Thereafter, the fully cured ALC panel has been manufactured by steam curing the semi-cured body at a high temperature and high pressure of about 183 ° C. and 1 MPa.

  Examples of the rust preventive material for ALC panel reinforcing steel bars include a cement type mainly composed of a cement solution (see, for example, Patent Documents 1 and 2), and an inorganic / rubber type mainly composed of an inorganic filler and rubber latex ( For example, various types such as Patent Documents 3 and 4) and a combination type using these in combination (for example, refer to Patent Document 5) are conventionally known.

  However, the cement-type rust preventive is heated at a high temperature of 80 to 100 ° C. in order to dry it in a short time. In this case, the moisture in the rust preventive is evaporated and solidified into a fine coating. As a result of the micropores being formed, moisture penetrates from the micropores during the subsequent high-temperature and high-pressure steam curing, and moisture that has penetrated into the panel after production penetrates from the micropores. As a result, the reinforcing steel bars rust. As a result, there is a problem that the rust prevention performance is lowered. In order to solve this problem, when using a cement type rust preventive material, the film thickness of the rust preventive material must be increased to about several millimeters, which not only increases the drying time, There was an adverse effect of increasing costs.

  In addition, according to the inorganic / rubber type rust preventive material, the use of rubber improves the denseness of the rust preventive material itself, but not only the adhesion to the panel base material, particularly the semi-cured material, is poor, but the aqueous solution Since it was used in a state, it included the problem that micropores were easily formed in the coating film during drying, as in the case of the cement-type rust preventive material.

  Furthermore, when using the above resin-type rust preventives as a resin-based aqueous emulsion by immersion, a certain degree of high viscosity is required to ensure film thickness, and the rust preventive is uniformly attached to the surface of the reinforcing steel bars. There is a problem that it is difficult to ensure a certain film thickness. Further, in order to solve this problem, when an organic solvent is mixed with an aqueous emulsion to lower the viscosity, there is a problem that special consideration is required for ensuring safety against volatilization of the organic solvent.

Furthermore, in the case of the above-mentioned combined type rust preventive material, since the problems included in each type are brought in, further improvement has been continually desired.

  In addition, in each of the conventional rust preventive materials described above, it is often performed to add a bituminous substance such as natural asphalt in order to improve rust prevention and film-forming properties (for example, see Patent Documents 1 and 5). ). In this case, although the corresponding effect can be obtained, this bitumen substance dissolves in the oil-based mold release agent applied to the hanging rod that suspends the reinforcing reinforcing bars during the rust prevention treatment, and therefore is extracted when the semi-cured product is produced. It remained on the hanger bar traces, and further wetted during curing of the main cured body and flowed out of the holes of the hanger bar traces, resulting in black stains around the hanger bar traces, and the appearance was impaired. As a result, there is a problem of lowering the commercial value of ALC panels, and moreover, since bituminous substances as natural materials are being depleted in recent years, anxiety about stable supply and the appearance of alternatives are desired. Is the actual situation.

Japanese Patent Publication No. 36-23879 Japanese Examined Patent Publication No. 45-15062 Japanese Patent Publication No. 60-7972 JP 50-97617 A JP 58-110456 A

  The present invention has been achieved as a result of studying the solution of the problems in the prior art described above as an issue.

  Accordingly, an object of the present invention is to provide ALC panel reinforcement that provides an ALC panel that is excellent in rust prevention, adhesion to reinforcing reinforcing bars and ALC panel base material, film-forming properties, quality stability and supply stability, and has a high commercial value. An object of the present invention is to provide a rust prevention material for reinforcing bars and an efficient rust prevention method using this rust prevention material.

  In order to achieve the above object, according to the present invention, there is provided a rust preventive material for reinforcing steel bars embedded in an ALC panel, which is an inorganic raw material, water, a resin emulsion, and a resin powder having a softening point of 165 ° C to 190 ° C. There is provided a rust preventive material for ALC panel reinforced reinforcing bars comprising a mixed solution containing a main component consisting of the above and other additives.

In addition, in the rust preventive material for ALC panel reinforcing steel bars of the present invention,
The inorganic raw material contains at least one selected from Portland cement, calcium carbonate, slaked lime, talc, silica stone powder, cryolite, clay, mica, diatomaceous earth, white clay, titanium oxide and bengara;
The other additive contains at least one selected from a cement hardening inhibitor, an adhesive, a dispersant, a water retention agent, an antifoaming agent, an alkalinity imparting agent, and a colorant;
The inorganic raw material has a particle size of 150 μm or less,
The resin emulsion is at least one selected from an acrylic resin, a polystyrene resin, a styrene / acrylic resin and an emulsion of a styrene / butadiene resin;
The resin powder is a resin powder having a particle size of 200 μm or less, and the resin powder is a polyamide-based resin powder,
It consists of a mixed solution in which 30 to 55 parts by weight of water, 3 to 30 parts by weight of resin emulsion, 1 to 15 parts by weight of resin powder, and 0 to 8 parts by weight of other additives are added to 100 parts by weight of the inorganic raw material. ,
Are mentioned as preferable conditions.

Moreover, the rust prevention method of the ALC panel reinforcement reinforcing bar of this invention is a rust prevention method of the reinforcement reinforcement embed | buried in an ALC panel, Comprising: The said reinforcement reinforcement is immersed in the said rust prevention material for said ALC panel reinforcement reinforcement. Then, the process of drying at a temperature of 80 to 130 ° C. is repeated at least once, and the film thickness of the rust preventive material applied to the reinforcing reinforcing bar surface after the immersion / drying process is 100 to 600 μm. Apply to be in the range of
Are preferable conditions.

  According to the present invention, as described below, an ALC panel having excellent rust prevention, adhesion to reinforcing reinforcing bars and panel base material, film-forming property, quality stability and supply stability, and high commercial value is provided. A rust preventive material for ALC panel reinforcing steel bars can be obtained.

Moreover, according to the rust prevention method of the present invention, it is possible to efficiently produce a reinforcing steel bar having a high rust prevention performance, in which the rust prevention material is uniformly and firmly applied. By using a reinforced anti-corrosion reinforcing bar, it is possible to obtain an ALC panel that is excellent in rust prevention, has a good surface appearance, and has a high commercial value.

  The present invention will be specifically described below.

  The rust preventive material for reinforcing reinforcing bars of the present invention (hereinafter simply referred to as rust preventive material) is composed of an inorganic raw material, water, a resin emulsion, and a main component and other additives composed of a resin powder having a softening point of 165 ° C to 190 ° C. And has a performance (film-forming property) for forming a rust-preventive coating on the surface of the reinforcing reinforcing bar by being applied to the reinforcing reinforcing bar by a dipping method and then dried. Is.

  The inorganic raw material constituting the main component of the rust preventive material of the present invention is at least one selected from Portland cement, calcium carbonate, slaked lime, talc, silica stone powder, cryolite, clay, mica, diatomaceous earth, white clay, titanium oxide and bengara. Usually, it is desirable to use a mixture of two or more of these. These inorganic raw materials are preferably in the form of a powder having a particle size of 150 μm or less, particularly 100 microns or less. In particular, since inorganic raw materials such as Portland cement can be easily combined with cement in the raw material slurry of the ALC panel, the rust preventive material and the ALC panel base material can be bonded more firmly, and the rust prevention property is improved. It is also a relatively inexpensive material and is recommended.

The resin emulsion that the rust preventive material of the present invention contains as an essential component is an acrylic resin, a styrene / acrylic resin, a styrene / butadiene resin, an acrylonitrile / butadiene resin, a polybutadiene resin, a polystyrene resin, or a polyurethane resin. An emulsion in which a resin such as a polyester resin is dispersed, and is a component that functions to impart film-forming properties and adhesiveness at about 100 ° C. to 130 ° C. with respect to the inorganic raw material. Since this resin emulsion is required to have a certain degree of water solubility and excellent heat resistance and alkali resistance, among these emulsions, acrylic resin emulsion, polystyrene resin emulsion, styrene / acrylic resin emulsion and styrene / butadiene are particularly preferred. The use of at least one selected from a resin emulsion is recommended. As these emulsions, those having a resin concentration of 30 to 70% by weight and generally marketed for cement mixing can be used as they are.

The resin powder having a softening point of 165 ° C. to 190 ° C. contained as an essential component in the rust preventive material of the present invention is preferably a resin powder having a particle size of 200 μm or less. The particle size of the resin powder is preferably 200 μm or less, particularly 160 μm or less because dispersibility in the rust preventive slurry is excellent. The resin powder is not particularly limited as long as it has a softening point in the above range and does not inhibit the hydration reaction of cement. Among them, nylon 6, nylon 66, nylon 6/66, nylon 11, nylon 12 are not particularly limited. Polyamide resins such as nylon 6/66 and nylon 11 are preferably used.

This resin powder is a component that functions to further enhance rust prevention, film-forming properties, and adhesion to the ALC panel base material. That is, in the drying process of the rust preventive material, even if fine micropores are formed in the coating as the moisture evaporates, the resin powder is softened during the subsequent high-temperature / high-pressure steam curing to form a resin film. In addition, since the resin film fills the micropores, the micropores in the rust preventive material are eliminated, a stable coating is formed, and excellent antirust properties that are not available in the past can be obtained. At the same time, bonding with the ALC panel base material is performed, which contributes to an improvement in the bending strength of the ALC panel.

  The rust preventive material of the present invention can contain additives as desired in addition to the above four components. These additive components include cement hardening inhibitors such as casein, adhesives such as Metroise, dispersants, water retention agents, antifoaming agents such as silicone compounds, hydration inhibitors (retarding agents) such as sodium boron hydride, Examples include alkalinity imparting agents such as caustic soda, colorants such as pigments and dyes, heat resistance agents, antioxidants, stabilizers and binders, among which cement hardening inhibitors, adhesives, antifoaming agents, and hydration inhibitors. In addition, the addition of an alkalinity imparting agent is recommended because it can further improve rust prevention.

  The mixing ratio of each component in the rust preventive material of the present invention is 30 to 55 parts by weight of water, 3 to 30 parts by weight of resin emulsion, 1 to 15 parts by weight of resin powder, and other additives with respect to 100 parts by weight of the inorganic raw material. It is selected from the range of 0 to 8 parts by weight.

  If the blended amount of the resin emulsion is less than 3 parts by weight, micropores tend to be generated during drying, and if it exceeds 30 parts by weight, the adhesion to the ALC cured body tends to decrease and the rust prevention performance tends to deteriorate. In particular, the range of 5 to 20 parts by weight is preferable.

  If the amount of water is less than 30 parts by weight, the film-forming property is hindered to make it difficult to form a film having a uniform thickness. Since generation | occurrence | production of a hole becomes remarkable, the range of 30-50 weight part is especially preferable.

  The blending amount of the resin powder is preferably in the range of 1 to 15 parts by weight, particularly 2 to 12 parts by weight with respect to 100 parts by weight of the inorganic raw material. Even if it exceeds the range, there is no difference in the adhesion and rust prevention performance with the ALC base material, and the cost increases.

  Moreover, since the effect of this invention may be inhibited when there are too many compounding quantities of another additive, it may be 8 weight part or less with respect to 100 weight part of inorganic raw materials, and especially 5 weight part or less. desirable.

  The rust preventive material of the present invention can be prepared by a conventionally known method, and as a specific preparation method, a slurry formed from an inorganic raw material and water, a resin emulsion and a resin powder having a softening point of 165 ° C. to 190 ° C. A method in which other additives are added and stirred, and a method in which a resin emulsion and an inorganic raw material are mixed and stirred in a slurry obtained by kneading a poorly soluble additive such as casein with water and a resin powder having a softening point of 165 ° C. to 190 ° C. Etc.

The rust preventive material of the present invention obtained by blending in this way is in the form of a slurry, and is used for rust prevention treatment by immersing a hook-shaped reinforcing steel in this slurry. Thus, the viscosity and concentration can be adjusted as appropriate by adding water and each additive component.

  Moreover, if the slurry after mixing is preserve | saved in the sealing state, the rust preventive material of this invention will be stable as long as there is no evaporation of a water | moisture content. Further, when sealing is difficult, if a curing inhibitor or hydration inhibitor is appropriately added, it does not solidify and does not deteriorate in performance, so that it can be used for a long time. Further, when the reinforcing steel bars are continuously immersed, even if the shortage is newly prepared and supplemented, the properties are not changed or the performance is not deteriorated.

  Next, a method for performing a rust prevention treatment of the reinforcing reinforcing bars using the above rust prevention material will be described.

  In carrying out the rust prevention method of the present invention, first, a hook-shaped reinforcing bar (diameter is 2.0) assembled in a hook shape of a desired shape according to the size of the ALC panel to be obtained and the size of the rust prevention tank. Prepare a plurality of reinforcing bars (about 9.0 mm).

  Then, a desired amount of the above-mentioned rust preventive material is supplied to the rust preventive tank, and the hook-shaped reinforcing bars are immersed in the rust preventive material to apply the rust preventive material to the reinforcing bar surface, and then 80 to 130 ° C. It is preferably dried at a temperature of 90 to 120 ° C. This dipping treatment is the conventional method described above, that is, suspending a plurality of hook-shaped reinforcing bars with a plurality of hanging rods coated with a release agent and transporting them to a rust-proofing process, and filling the rust-proofing material. What is necessary is just to carry out similarly to the method of immersing a hook-shaped reinforcement bar in a tank and pulling it up.

  Drying of the rust-preventing material after it has been lifted from the rust-proof tank can be performed using a normal hot-air heating furnace or hot-air drying furnace, but in this case, it does not cause the phenomenon of peeling or pulling of the coating film. For this purpose, it is necessary to avoid the use of rapid drying conditions and to set appropriate drying conditions in accordance with the production line speed.

  Here, if the drying temperature is less than 80 ° C., not only the drying time is lengthened but also the thickness of the coating becomes non-uniform. Conversely, if the drying temperature exceeds 130 ° C., the generation of micropores due to rapid water evaporation becomes remarkable, which is not preferable. .

  In addition, it is preferable to repeat the same immersing / coating / drying treatment at least once after the dipping / coating / drying treatment in this rust-proofing treatment, thereby obtaining further excellent rust-proofing performance. it can.

  In the rust prevention treatment, the treatment conditions are controlled so that the film thickness of the rust prevention material applied to the surface of the reinforcing steel by immersion, coating, and drying treatment is in the range of 100 to 600 μm, particularly 150 to 500 μm. It is desirable to do. Here, if the thickness of the rust preventive coating obtained by dipping / coating / drying treatment is less than 100 μm, the desired rust preventive effect may not be obtained. There is no big effect and it is economically disadvantageous. In addition, in order to make the film thickness of a rust preventive material into 100-600 micrometers, after immersing this reinforcement bar in the rust prevention liquid whose viscosity of the solution was adjusted to 500-20,000 mPa * S, it is 5-20 cm per second. It is good to raise.

  Thus, after the rust-proof reinforcing bar subjected to the rust prevention treatment is placed in the mold while being suspended from the suspension rod, the raw slurry of the ALC panel is injected into the mold, Curing proceeds and a semi-cured product is formed. Next, after the suspension bar is pulled out from the semi-cured body, it is cut into a predetermined dimension with a piano wire. Then, the fully cured ALC panel is manufactured by steam curing at a high temperature and high pressure of about 183 ° C. and 1 MPa.

And even if micropores are generated in the coating film in the drying process, the resin powder having a softening point of 165 ° C. to 190 ° C. contained in the rust preventive material is softened in this high temperature / high pressure steam curing process. Since a resin film is formed and this resin film fills the micropores, the micropores are blocked and a more stable film is formed, and an excellent antirust property that has not been obtained conventionally can be obtained. Further, in the steam curing process at high temperature and high pressure, the ALC panel base material and the rust preventive material of the reinforcing steel bars are more firmly bonded, so the performance as the ALC panel is improved.

Therefore, according to the present invention, the following excellent effects can be obtained.

  (1) An excellent antirust effect can be maintained over a long period of time. That is, since the micropores, which are film defects generated in the drying process, are blocked in the steam curing process, the surface of the reinforcing reinforcing bars is not touched by air or moisture, and the rust prevention performance is significantly improved.

  (2) Since the adhesion between the rust-proofing material and the reinforcing steel bar, and between the rust-proofing material and the ALC panel base material is excellent, the bonding strength between the ALC panel and the reinforcing steel bar is high, so that bending, impact, or deformation occurs during transportation of the ALC panel. Even if such a load is applied, defects such as cracks are not generated in the rust preventive coating, and the durability of the rust preventive effect is high.

  (3) Since it does not contain organic solvents, it does not require special considerations for ensuring safety in consideration of environmental sanitation in the work environment, and is excellent in terms of economy and safety.

  (4) Since it is excellent in quality stability, it is stable by suppressing the evaporation of moisture even if stored for a long period of time. In addition, when a hardening inhibitor, a hydration inhibitor, or the like for Portland cement is appropriately added, problems such as solidification do not occur over a long period of time.

  (5) Since rare materials such as bituminous materials are not required, not only the supply stability is excellent, but also the appearance merchandise deterioration caused by the bituminous materials is eliminated, and an ALC panel with high commercial value can be obtained. it can.

  (6) It is possible to efficiently manufacture an ALC panel in which a reinforced reinforcing bar having a high rust prevention performance, in which a rust preventive material is uniformly and firmly applied around the reinforcing reinforcing bar.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

  In addition, the characteristic evaluation in an Example and a comparative example was performed by the method described below.

[Rust prevention]
Reinforced reinforcing bars (rebar diameter: 5 mm) coated with a rust preventive material are taken out from the ALC panel after steam curing, and rusting rate is measured and evaluated after 500% spraying of 5% salt water according to JIS K5400. did. Rust generation rate of 1.0% or less was accepted.

[Adhesiveness]
About the ALC panel after the steam curing, the bonding strength between the ALC panel material and the reinforcing reinforcing bar coated with the rust preventive material was measured according to RIREM AAC 9.1 “Reinforcing bar pull-out test” to evaluate the adhesion. A bonding strength of 1.5 N / mm ² or more was accepted.

[Film-forming properties]
The reinforcing steel bars after the rust preventive material was applied and dried were evaluated by the water absorption after being immersed in water for 2 hours. That is, an increase in weight due to moisture permeation from the micropores formed in the rust-preventing material coating of the reinforcing reinforcing bars was determined, and the film forming property was evaluated based on the result. ◎ and ○ were accepted, and Δ and x were rejected.
◎ Water absorption is less than 1% (sufficiently strong film is formed)
○ Water absorption is 1% to less than 2% (a certain degree of strong film is formed)
Δ: Water absorption is less than 2 to 3% (water penetration into the film is somewhat severe)
× Water absorption is 3% or more (water penetration into the film is severe)

[Product appearance]
About the ALC panel after steam curing, the external appearance was evaluated visually and it determined by the following 2 levels.
○ There is no dirt due to the rust preventive material, and the appearance is very good and no problem. (Pass)
× The area around the hanging rod mark is black and dirty, and the product value is reduced. (failure)

[Examples 1-6 and Comparative Examples 1-7]
The vertical streaks (diameter: 5 mm) embedded in the length direction of the ALC panel and the horizontal streaks (diameter: 4 mm) embedded in the width direction are connected in a lattice shape to form a flat mat, and two flat mats are used. By connecting and forming a hook shape, a plurality of hook-shaped reinforcing bars having a thickness x width x height = 70 x 480 x 2960 mm were prepared.

  On the other hand, slurry-like rust preventive materials for Examples and Comparative Examples were prepared by mixing the following components in proportions (weight ratios) shown in Table 1.

(Main component)
Inorganic raw materials: “Ordinary Portland cement” manufactured by Taiheiyo Cement Co., Ltd. “Heavy calcium carbonate (special powder)” manufactured by Kawai Lime Industry Co., Ltd. “Slaked lime (special powder)” manufactured by Kawai Lime Industry Co., Ltd./ Tokai Industry An inorganic material was prepared by mixing “silica stone (special powder)” manufactured by Co., Ltd. at a ratio (weight ratio) of 75/10/10/5.
Water: Tap water Resin emulsion: “Rikabond” (acrylic resin emulsion) manufactured by Chuo Rika Kogyo Co., Ltd.
Resin powder: “Best Ginto 1111” (Nylon 11, softening point 176 ° C.) manufactured by Daicel Tegusa Corporation
“CM40F” manufactured by Toray Industries, Inc. (nylon 6/66, softening point 179 to 184 ° C.)
(Additive)
Casein: “New Zealand casein” manufactured by Nissei Kyoyoku Co., Ltd.
Metroise: "SM 1500" (adhesiveness, dispersibility, water retention) manufactured by Shin-Etsu Chemical Co., Ltd.
Caustic soda: Central Chemical Co., Ltd. (alkaline)
Defoamer: “Adecanate” manufactured by Asahi Denka Kogyo Co., Ltd.
Retardant: “B90B” manufactured by Croda Japan Co., Ltd.
(Comparative resin powder)
Petroleum-based resin powder: “Arcon P140” (softening point 140 ° C.) manufactured by Arakawa Chemical Industries, Ltd.
Rosin resin powder: “Pencel D160” (softening point 158 ° C.) manufactured by Arakawa Chemical Industries, Ltd.
Polypropylene resin powder: “Biscol 660P” (softening point 145 ° C.) manufactured by Sanyo Chemical Industries
Bituminous and natural asphalt powder: "Gilsonite" manufactured by American Gilsonite (softening point 160 ° C)

  And after immersing the hook-shaped reinforcement reinforcing bar of the state hung with the hanging rod in the rust prevention tank filled with each rust prevention material slurry so that the whole is immersed in the rust prevention material, each in Table 2 Dry with warm air at the indicated temperature for 10 minutes.

  Further, in Examples 1, 2, 4, 5 and Comparative Examples 2 to 5, the reinforced reinforcing bars after drying were dipped once more in a rust prevention tank and then dried with warm air at 120 ° C. for 10 minutes. In Comparative Examples 6 and 7, the drying conditions were changed as shown in Table 2. Table 2 shows the results of evaluating the film-forming property at this point.

  Next, 30 saddle-shaped reinforcing bars with rust-preventive coatings formed on the surface were placed in the mold in a state of being suspended from the suspension rod, and the raw material slurry for the ALC panel was injected into the mold Then, after the foaming and curing of this raw material slurry were advanced to make a semi-cured body, the suspension rod was pulled out from the semi-cured body. In addition, as raw material slurry, 60 parts by weight of water was added to 44 parts by weight of silica powder, 16 parts by weight of quicklime powder, 11 parts by weight of Portland cement, and 29 parts by weight of recycled powder of ALC panel, and the mixture was stirred and mixed with a mixer. Thereafter, a slurry in which 0.065 parts by weight of aluminum powder was added to 100 parts by weight of the powder raw material was used.

  Thereafter, the semi-cured material is removed from the mold, and after being cut into a predetermined dimension (thickness × width × length = 100 × 600 × 2990 mm) with a piano wire, steam curing is performed at a high temperature and high pressure of 183 ° C. and 1 MPa. A fully cured ALC panel was produced.

  Table 1 shows the blending ratio of each rust preventive. Table 2 shows the results of evaluating the rust prevention, adhesion, and product appearance of the ALC panel with the drying conditions, each film thickness, and the obtained ALC panel.

  As is clear from the results of Tables 1 and 2, according to the rust preventive material of the present invention, an ALC panel having excellent balance of rust preventive property, adhesive property, film forming property and product appearance can be obtained (implementation). Examples 1-6). On the other hand, when the film thickness is less than 100 μm (Comparative Example 1), the rust preventive material not containing the resin powder of the present invention (Comparative Examples 2 to 5) can obtain the rust preventive effect that is particularly targeted by the present invention. Of these, the anticorrosive material containing the bituminous substance (Comparative Example 5) was able to achieve only the ALC panel, although the anticorrosive property was cleared, but the anticorrosive material eluted from the trace of the hanging rod and the product appearance was inferior. There wasn't. Further, when the drying temperature is too low (Comparative Example 6), the rust prevention property, adhesion and film forming property are inferior. On the contrary, when the drying temperature is too high (Comparative Example 7), the rust prevention property and film forming property are inferior. .

As described above, according to the present invention, an ALC panel having excellent rust resistance, adhesion to reinforcing reinforcing bars and ALC panel base material, film-forming property, quality stability, easy to obtain, and high commercial value is provided. Since a rust preventive material for ALC panel reinforced reinforcing bars can be obtained, and a reinforced reinforcing bar having a high rust prevention performance can be efficiently produced by applying the rust preventive material uniformly and firmly. By using reinforced reinforcing bars rust-prevented by this method, it is possible to obtain an ALC panel having a good surface appearance and excellent rust-preventing property and high commercial value as a building material.

Claims (10)

Rust preventive material for reinforcing steel bars embedded in lightweight cellular concrete panel, comprising inorganic raw material, water, resin emulsion, main component consisting of resin powder having softening point of 165 ° C to 190 ° C, and other additives A rust preventive material for lightweight cellular concrete panel reinforced steel, comprising a mixed solution. The light weight according to claim 1, wherein the inorganic raw material contains at least one selected from Portland cement, calcium carbonate, slaked lime, talc, silica stone powder, cryolite, clay, mica, diatomaceous earth, white clay, titanium oxide, and bengara. Rust-proofing material for cellular concrete panel reinforcement. The lightweight cellular concrete panel reinforcing steel bar according to claim 1 or 2, wherein the other additive comprises at least one selected from a cement hardening inhibitor, an adhesive, a dispersant, a water retention agent, an antifoaming agent, and a colorant. Rust preventive material. The particle size of the said inorganic raw material is 150 micrometers or less, The rust preventive material for lightweight cellular concrete panel reinforcement steel bars of any one of Claims 1-3. The lightweight foam according to any one of claims 1 to 4, wherein the resin emulsion is at least one selected from emulsions of acrylic resins, polystyrene resins, styrene / acrylic resins, and styrene / butadiene resins. Rust prevention material for concrete panel reinforcement. The said resin powder is a resin powder with a particle size of 200 micrometers or less, The rust preventive material for lightweight cellular concrete panel reinforcement steel bars of any one of Claims 1-5. The said resin powder is a polyamide-type resin powder, The rust preventive material for lightweight cellular concrete panel reinforcement steel bars of any one of Claims 1-6. 30 to 55 parts by weight of water, 3 to 30 parts by weight of a resin emulsion, 1 to 15 parts by weight of a resin powder having a softening point of 165 to 190 ° C., and 0 to 8 parts of other additives with respect to 100 parts by weight of the inorganic raw material The rust preventive material for lightweight cellular concrete panel reinforced steel bars according to any one of claims 1 to 7, comprising a mixed solution to which a part is added. It is a rust prevention method of the reinforcement reinforcement embed | buried in a lightweight cellular concrete panel, Comprising: The said reinforcement reinforcement is immersed in the rust prevention material for lightweight cellular concrete panel reinforcement reinforcement of any one of Claims 1-8. And the process of drying at a temperature of 80 to 130 ° C. is then repeated at least once or more, and the method for rust prevention of a lightweight cellular concrete panel reinforced steel bar is characterized. The rust preventive method for lightweight cellular concrete panel reinforced reinforcing bars according to claim 9, wherein the rust preventive material coated on the reinforcing reinforcing bar surface by the dipping / drying treatment is processed such that the film thickness is in a range of 100 to 600 µm.