JP6296284B2 - Concrete member and manufacturing method thereof - Google Patents

Description

  The present invention relates to a concrete member.

  In recent years, the unique colors and textures of wood transferred to concrete bring out natural-looking aesthetics and warmth, so that there are an increasing number of buildings and structures made of wood-like makeup.

  Various methods for enhancing the color and texture of concrete after finishing have been proposed for the natural finish of buildings and structures. For example, in Patent Document 1, a coating agent containing a synthetic resin emulsion and a granular material having an average particle diameter of 0.1 to 1.0 mm on a wall surface or the like and having a granular particle content of 5 to 80% by weight is applied. After adding, it contains one or more kinds of powders selected from synthetic resin emulsion, natural stone having an average particle diameter of 5 μm to 3.0 mm, colored aggregate, and vegetable powder, and the solid content of the synthetic resin emulsion is 100 parts by weight. Distribute and apply a finish coating agent containing 100 to 1000 parts by weight of powder and granule, and give a pattern to the surface of the finish coating agent with a pattern roller before the finish coating agent is completely cured. A coating method is disclosed.

Further, for example, Patent Document 2 discloses a natural-tone cosmetic material produced by applying a coating agent on a pattern with uneven density and unevenness and a smooth portion and a rough surface portion formed on the surface of a mortar base material. It is disclosed.
Furthermore, for example, in Patent Document 3, a mold is formed using a template obtained by laminating a printing base paper on which a pattern is printed using ink having almost no water absorption on a plywood. A method for placing decorative concrete is disclosed in which concrete is poured to form a concrete surface having a density corresponding to the printing of a pattern.

JP 2008-253913 A JP-A-1-127330 JP-A-62-227800

  However, in natural finishes, not only the surface irregularities and patterns, but also the aesthetics and warmth brought out from the concrete members change depending on the color. In conventional concrete finishing methods and coatings, the color of the concrete after finishing is easily affected by the mixing conditions of the concrete and the coating agent and the construction, and the colors such as yellow and green that give a wood-like texture are concrete. There is a problem that the surface does not settle stably and the finish is different from the designer's intention. There is also a problem that there is little academic knowledge about the color after the makeup finish, and the reproducibility of the color depends largely on the experience of the workers.

  This invention is made | formed in view of the said situation, and makes it a subject to provide the concrete member colored in the texture like natural wood.

(1) The following general formula (P1) is applied to the surface of concrete based on one or more cements selected from the group consisting of ordinary Portland cement, moderately hot Portland cement, low heat Portland cement, early strong Portland cement and blast furnace cement. A concrete colorant containing a phenolic compound represented by the formula:

[Wherein, R represents an n-valent organic group, m represents an integer of 1 to 5, and n represents an integer of 1 or more. ]

  The colored surface of the concrete member of the above (1) is colored to a natural wood-like texture (hereinafter sometimes referred to as “wood-like”). You can enhance the aesthetics of the building and express the warmth and warmth of wood.

(2) The concrete member according to (1), wherein the concrete contains lime crushed sand.
According to the concrete member of the above (2), a natural wood having a phenolic compound attached to the concrete surface by reflecting the beautiful color derived from crushed lime sand on the colored surface and adding the color of crushed lime sand. You can further enhance the shades.

(3) The concrete member according to (1) or (2), wherein the phenolic compound is lignin or tannin.
According to the concrete member of the above (3), it is possible to express a more natural wood texture by taking advantage of the color of wood of lignin and tannin attached to the concrete surface.

(4) The concrete member according to (1) or (2), wherein the phenolic compound is gallic acid.
According to the concrete member of the above (4), it is possible to express a more natural wood texture by utilizing the color tone of the wood possessed by the gallic acid attached to the concrete surface.

(6) by dipping the wood in an aqueous solvent, a step of extracting a phenolic compound represented by the following general formula (P1), the concrete colorant comprising a phenolic compound, ordinary Portland cement, moderate heat portland cement, low heat Portland cement, the production of concrete parts you and a step of attaching the early-strength Portland cement and one or more cement selected from the group consisting of blast furnace cement to the surface of the concrete to the base material, the Way .
According to the concrete member manufactured by the manufacturing method of ( 6 ) above, the color of the pigment containing a plurality of kinds of compounds extracted from the actual wood attached to the concrete surface is utilized to make the natural wood more natural. The texture can be expressed.

( 7 ) The method for producing a concrete member according to ( 6 ), wherein the phenolic compound is extracted by immersing the wood in an aqueous solvent having a pH of 4 or more.
According to the concrete member produced by the production method of ( 7 ) above, a pigment comprising a plurality of compounds having excellent color developability, which is attached to the concrete surface and extracted from actual wood using an aqueous solvent having a pH of 4 or higher. By taking advantage of the color tones, it is possible to express a more natural wood texture.

( 8 ) The method for producing a concrete member according to ( 6 ) or ( 7 ), wherein the wood is cedar, lauan, or larch.
According to the concrete member produced by the production method of ( 8 ) above, a texture relatively close to the raw material wood is expressed by utilizing the color of the pigment extracted from cedar, lauan or larch attached to the concrete surface. can do.

( 5 ) The concrete member according to any one of (1) to ( 4 ), wherein unevenness of a wood pattern is formed on a colored surface of the concrete member.
According to the concrete member of ( 5 ) above, the same shade as the surface of natural wood appears due to the unevenness of the wood pattern (wood grain) formed on the colored surface as well as the color of the colored surface. The texture of wood can be expressed.

  Since the colored surface of the concrete member of the present invention is colored like natural wood, it can be used as a member of a building to enhance the aesthetics of the building, and warmth and warmth of wood. Can be expressed.

It is a schematic diagram which shows the concrete member which is 1st embodiment of this invention. It is a figure which shows the method of manufacturing the concrete member which is 1st embodiment of this invention, Comprising: It is a schematic diagram which shows a mode that concrete was laid in the formwork. It is a figure which shows the method of manufacturing the concrete member which is 1st embodiment of this invention, Comprising: It is a schematic diagram which shows a mode that a concrete colorant is apply | coated to the surface of a concrete member. It is a schematic diagram which shows the concrete member which is 2nd embodiment of this invention. It is a figure which shows the method to manufacture the concrete member which is 2nd embodiment of this invention, Comprising: It is a schematic diagram which shows the formwork for placing concrete. It is a figure which shows the method of manufacturing the concrete member which is 2nd embodiment of this invention, Comprising: It is a schematic diagram which shows a mode that a concrete member is formed. 2 is a photograph of a scanning electron microscope showing a cross section of a specimen in Example 1. FIG. It is a figure which shows element distribution of the measurement surface of the test body in Example 1, Comprising: (a) is a figure which shows calcium element distribution, (b) is a figure which shows carbon element distribution. It is a graph which shows the total amount of organic carbon extracted from each of the non-colored part and the colored part of the test body in Example 1 to pH adjusted aqueous solution. 2 is a graph showing the absorbance of an extraction solution obtained from a cedar piece in Example 1. FIG. It is a graph which shows the change of the brightness by drying of the concrete used for each mockup in Example 2. FIG. It is a graph which shows the change of b ^* by drying of the concrete used for each mockup in Example 2. FIG. It is a graph which shows the influence of the kind of wooden board of a formwork on the brightness of the concrete used for each mockup in Example 3. FIG. It is a graph which shows the influence of the kind of wooden board of a formwork on b ^* of the concrete used for each mockup in Example 3. FIG. 6 is a plan view showing a test body in Example 5.

(First embodiment)
Drawing 1 is a mimetic diagram showing decorative concrete 2 (concrete member) of this embodiment.
The decorative concrete 2 has a concrete colorant containing a phenolic compound (compound P1 described later) that emits a natural tone color not shown on the decorative surface 4a (surface) of the concrete member 4 constituting the building or structure. It is.
Here, the phrase “attached” to the concrete colorant is a term including “applied”, “impregnated” and “transferred”.

  The concrete colorant has also penetrated into the concrete member 4 on the inner side of the fixed thickness dimension from the decorative surface 4a. In the concrete member 4, the decorative surface 4 a and a portion impregnated with the compound P <b> 1 having a certain thickness inside from the surface are referred to as a colored layer 4 d. The thickness dimension of the colored layer 4d is about 400 μm.

  The concrete member 4 is made of a concrete based on one or more cements selected from the group consisting of ordinary Portland cement, moderately hot Portland cement, low heat Portland cement, early-strength Portland cement, and blast furnace cement. Of the total weight of the cement constituting the concrete member, the content of the one or more cements used as the base material is preferably 50 to 100% by weight, more preferably 70 to 100% by weight, and further 90 to 100% by weight. preferable.

  The early strength Portland cement does not significantly change the brightness of the decorative surface 4a due to drying. Moreover, in the blast furnace cement, the lightness of the decorative surface 4a accompanying drying increases. Further, in the low heat Portland cement or blast furnace cement, the yellow or brown color peculiar to the compound P1 on the decorative surface 4a becomes darker with drying, and the natural tone is deepened as a whole. The cement used as the base material of the concrete member 4 is appropriately selected from the above group in consideration of the difference in color shade of the decorative surface 4a depending on the type of cement.

  The water cement ratio (water mass / cement mass) of the concrete member 4 is appropriately set in consideration of the type of cement as the base material. Usually, the water cement ratio is preferably 30 to 60%.

  It is preferable that the concrete member 4 contains lime crushed sand as a fine aggregate. By including the crushed lime sand, a natural tone color is deepened immediately after demolding, and the color tone can be stably maintained even when drying progresses.

<Formation of concrete member 4>
As shown in FIG. 2, first, a mold 10 made of wooden plywood, steel, resin or the like that matches the size of the concrete member 4 is assembled. The rectangular mold 10 shown in FIG. 2 is an example, and other shapes may be used. Next, concrete 12 constituting the concrete member 4 is placed in the mold 10 and solidified (cured).

  The age of the concrete 12 is preferably set as appropriate in consideration of the type of the concrete 12 used, the strength required for the concrete member 4, the color of the finished decorative concrete 2 and the like. Thereafter, the concrete member 4 is manufactured by removing the mold 10.

<Coloring of concrete member 4>
Subsequently, as shown in FIG. 3, a concrete colorant 13 described later is attached to the decorative surface 4 a of the concrete member 4. In addition, since a high concentration lignin may suppress solidification of the concrete 12, it is preferable that the amount of lignin contained in the concrete colorant 13 is an amount that does not inhibit the solidification of the concrete 12.
Here, “attaching” a concrete colorant is a term including “applying”, “impregnating”, and “transferring”.

  The method for applying the concrete colorant 13 to the decorative surface 4a of the concrete member 4 is not particularly limited. For example, a method of applying the concrete colorant 13 to the decorative surface 4a of the concrete member 4 using a brush or the like can be employed. In addition, as another method of applying the concrete colorant 13 to the concrete member 4, there is a method of placing the concrete 12 after applying the concrete colorant 13 to the surface of the mold 10 that contacts the decorative surface 4 a. An example of this method will be described later as a second embodiment.

Next, the concrete colorant 13 applied to the decorative surface 4a is dried. In terms of suppressing the color change of the decorative surface 4a of the concrete member 4, it is preferable that within 7 days after the applied concrete colorant 13 is dried, the decorative surface 4a of the concrete member 4 (that is, ) Is preferably coated with clear.
The decorative concrete 2 is completed through the above steps.

  In this embodiment, the concrete colorant 13 is applied to the decorative surface 4a of the concrete member 4, and the decorative surface 4a of the concrete member 4 is easily and stably applied to the concrete surface by adhering or penetrating the compound P1 to the concrete surface. It is possible to enhance the aesthetics and the warmth that are produced from the decorative concrete 2 by coloring in a natural tone color.

  Further, by making the surface layer portion of the concrete member 4 alkaline, preferably by adjusting the pH to 10 or more, the coloring of the compound P1 such as tannin and lignin becomes darker, and the decorative surface 4a of the concrete member 4 is colored with good coloring. It becomes possible to do. Since concrete is essentially alkaline, the surface layer is coated with clear (transparent surface coating material) so that the surface layer is not neutralized by carbon dioxide in the air. Part can be kept alkaline.

(Second embodiment)
FIG. 4 is a schematic diagram showing decorative concrete 3 manufactured using the concrete coloring method of the present embodiment. In addition, the same code | symbol is attached | subjected to the component same as the decorative concrete 2 of 1st embodiment among the components of the decorative concrete 3 shown in FIG. 4, and the description is abbreviate | omitted.

As shown in FIG. 4, in the decorative concrete 3, a concrete colorant is applied to the decorative surface 4a of the concrete member 4, a phenolic compound (compound P1) described later penetrates into the colored layer 4d, and the decorative surface 4a. A concavo-convex pattern of a wood pattern (grain) is formed. Due to the unevenness of the wood pattern, the decorative concrete 3 further brings out the beauty and warmth characteristic of wood.
Hereinafter, the manufacturing method of the decorative concrete 3 of 2nd embodiment is demonstrated.

<Formation of concrete member 4>
First, as shown in FIG. 5, a mold 10 that matches the size of the concrete member 4 is assembled. At this time, as a bottom plate of the mold 10, a wooden mold 14 (wood) having a concavo-convex pattern of wood pattern facing the inside of the mold 10 is installed. As the side plate of the mold 10, a wooden mold 14 similar to the bottom plate may be used, or a mold material made of steel or resin may be used. Note that the bottom plate of the mold 10 is not necessarily made of wood, and may be made of synthetic rubber other than wood, metal, or the like as long as it has a phase shape.

  Here, the “phase shape” means an uneven shape capable of imparting desired unevenness to the decorative surface of the concrete to be placed. For example, when a bottom plate having wood pattern irregularities is used, the surface of the concrete placed in contact with the bottom plate is transferred with irregularities in which the irregularities of the bottom plate are inverted to make up the makeup having the wood pattern irregularities. A surface can be formed.

  Next, as shown in FIG. 6, the concrete 12 constituting the concrete member 4 is placed in the mold 10 and solidified (cured). The kind of concrete used here is not particularly limited. The age of the concrete 12 is preferably set appropriately in consideration of the type of the concrete 12 used, the strength required for the concrete member 4, the color of the finished decorative concrete 3 and the like.

  The concrete member 4 is manufactured by removing the mold 10 after the concrete 12 is solidified. As a result, as shown in FIG. 6, the concavo-convex pattern of the wood pattern is transferred to the surface 12 p of the concrete 12 that has been in contact with the wooden mold (bottom plate) 14 of the mold 10, and the surface is applied to the decorative surface 4 a of the concrete member 4. It can be.

<Coloring of concrete member 4>
Subsequently, the concrete colorant 13 is applied to the decorative surface 4 a of the concrete member 4. The coating method and the drying method can be performed in the same manner as described in the first embodiment.

Further, as a concrete coloring method in the present embodiment, a concrete colorant 13 may be applied in advance to the surface of the mold (bottom plate) 14 in contact with the concrete 12 before the concrete 12 is placed on the mold 14. Good. By this method, the color derived from the compound P1 contained in the concrete colorant is transferred to the surface 12p of the concrete 12 in contact with the mold 14 simultaneously with the uneven pattern of the wood pattern. Therefore, immediately after demolding, the concrete colorant 13 is applied to the decorative surface 4a of the concrete member 4 (attached state), and the coloring process of the concrete member 4 after demolding becomes unnecessary.
The decorative concrete 3 is completed through the above steps.

  In this embodiment, the concrete colorant 13 is applied to the decorative surface 4a of the concrete member 4, and the decorative surface 4a of the concrete member 4 is easily and stably applied to the concrete surface by adhering or penetrating the compound P1 to the concrete surface. It is possible to enhance the aesthetics and the warmth born from concrete by coloring the natural tone of the material. Further, by making the surface layer portion of the concrete member 4 alkaline by using the same method as in the first embodiment, the coloring of the compound P1 such as tannin and lignin becomes dark, and the decorative surface 4a of the concrete member 4 has a good coloring property. It becomes possible to color.

  Further, in the present embodiment, concrete 12 is formed by placing concrete 12 on a mold 10 using a wooden mold 14 having a phase shape, so that the decorative surface 4a of the concrete member 4 has a characteristic of wood. An uneven pattern is formed, and it is possible to further enhance the aesthetics and the warmth brought out from the decorative concrete 3.

<Concrete colorant>
The embodiment of the concrete colorant used in the present invention contains a phenolic compound represented by the following general formula (P1). In general formula (P1), R represents an n-valent organic group, m represents an integer of 1 to 5, and n represents an integer of 1 or more. R is bonded to n phenolic hydroxyl groups.

  The mechanism by which the concrete colorant used in the present invention can be colored to a color close to natural wood by adhering the concrete colorant to the concrete surface is not necessarily clear, but the phenolic compound contained in the concrete colorant and / or its It is presumed that the hydrolyzate binds iron (iron ions) or other metal components present on the concrete surface to form a complex and becomes a pigment close to natural wood. Therefore, the phenolic compound represented by the general formula (P1) (hereinafter sometimes referred to as “compound P1”) only needs to have a phenolic hydroxyl group capable of binding iron or other metal components. . Here, the phenolic hydroxyl group means a group represented by the following general formula (q1). In general formula (q1), m represents an integer of 1 to 5, and a bond separated by a wavy line represents a monovalent bond.

  R in the general formula (P1) may be an n-valent organic group, and the number of carbon atoms of the organic group is not particularly limited, but is preferably 1 to 1000, for example. The organic group is preferably a hydrocarbon group, and more preferably a compound in which a hydrogen atom constituting a linear, branched or cyclic alkane is substituted with a phenolic hydroxyl group. In general formula (P1), n represents the number of phenolic hydroxyl groups. n should just be a natural number, for example, it is preferable that it is an integer of 1-100. When n is 2 or more, m in the plurality of phenolic hydroxyl groups represented by the general formula (q1) each independently represents 1 to 5, and each m is preferably 1 to 3 independently.

  Among the alkanes, a part of the alkylene group constituting the linear alkane may be substituted with a cyclic alkylene group or a phenylene group, and a part of the alkylene group constituting the branched chain alkane is a cyclic alkylene group or phenylene. It may be substituted by a group. Any or all of the hydrogen atoms constituting the cyclic alkylene group and the phenylene group are any of a hydroxyl group (—OH), a carboxyl group (—C═O—OH), an alkoxy group having 1 to 5 carbon atoms, or a halogen atom. One or more may be substituted. In addition, the branched chains of the branched chain alkane are bonded to each other through one or more divalent linking groups selected from a single bond, an oxygen atom (—O—), and an alkylene group having 1 to 5 carbon atoms. A typical ring may be formed. In this case, it is preferable that the terminal hydrogen atom constituting the branched chain is substituted with the divalent linking group.

The methylene group (—CH ₂ —) constituting the alkane is substituted by one or more of an oxygen atom (—O—), a carbonyl group (—C═O—), or a vinylene group (—CH═CH—). May be. Further, the hydrogen atom constituting the alkane, the alkylene group or the phenylene group is any one of a hydroxyl group (—OH), a carboxyl group (—C═O—OH), an alkoxy group having 1 to 5 carbon atoms, or a halogen atom. Or may be substituted by one or more.

  Suitable compounds P1 include, for example, catechins, lignins and tannins that are commonly contained in a variety of woods. By including any one or more of catechin, lignin and tannin in the concrete colorant, the concrete color has a more natural wood texture by utilizing the color of the wood of catechin, lignin and tannin attached to the concrete surface. The surface can be colored.

Here, “tannin” is a term that includes catechin, tannic acid, gallic acid, and the like, and is a general term for water-soluble compounds that are generally derived from plants, and is hardly soluble by reacting with metal ions, alkaloids, proteins, and the like. A salt, complex, or compound that forms a complex. “Catechin” is a known compound represented by a composition formula of C ₁₅ H ₁₄ O ₆ , and here is a term including a polyphenol compound as a derivative thereof. “Lignin” is a known aromatic polymer compound known as a phenolic compound involved in lignification of higher plants.

  Further, tannic acid and gallic acid represented by the following formula can also be exemplified as suitable compounds P1. By including tannic acid and / or gallic acid in the concrete colorant, the concrete surface can be made more natural to the texture of the wood by taking advantage of the color of the timber and / or gallic acid adhering to the concrete surface. Can be colored.

 An ester compound of gallic acid can also be used as compound P1. Examples of such ester compounds include propyl gallate, isoamyl gallate, and epigallocatechin gallate.

 When the tannic acid is contained in the concrete colorant, the concentration thereof is not particularly limited. For example, the content is preferably 0.1 to 40% by weight, more preferably 1 to 20% by weight, based on the total volume of the colorant. 10% by weight is more preferred.

 When gallic acid is contained in the concrete colorant, the concentration is not particularly limited, but is preferably 0.1 to 40% by weight, more preferably 1 to 20% by weight, based on the total volume of the colorant, 10% by weight is more preferred.

 The solvent constituting the concrete colorant is not particularly limited as long as it can dissolve or disperse the compound P1, and may be an aqueous solvent or an organic solvent.

  The aqueous solvent is not particularly limited as long as it is a solution containing water as a main component and containing 50% by weight or more of water with respect to the total volume of the solvent. For example, it may be purified pure water, an aqueous solution containing an acid or alkali, or a known pH buffer solution containing a pH-adjustable buffer. Moreover, organic solvents, such as alcohol miscible with water, may be included.

 The concrete colorant used in the present invention may be prepared by dissolving or dispersing chemically synthesized compound P1 in an appropriate solvent, or using compound P1 extracted from natural wood as an appropriate solvent. It may be prepared by dissolving or dispersing.

 For example, by immersing wood in an aqueous solvent, a plurality of types of compounds including the compound P1 can be extracted into the solvent. Such compounds may include unidentified compounds in addition to phenolic compounds such as tannic acid and gallic acid. By attaching a pigment composed of a compound extracted from wood to the concrete surface, it is possible to color the texture of wood more naturally.

 The pH of the aqueous solvent in which the wood is immersed is preferably 4 or higher, more preferably 7 or higher, and still more preferably 9 or higher. The compound P1 extracted with an aqueous solvent having a pH of 4 or more has excellent color developability and can color the concrete surface as if it were wood. In addition, the wood-derived compound P1 extracted with an alkaline aqueous solvent is particularly excellent in color developability.

  The kind of the wood immersed in the aqueous solvent for extracting the compound P1 is not particularly limited, and a known wood containing lignin or tannin can be used. For example, by using cedar, lawan, larch, etc., a compound capable of coloring the concrete surface in a color having excellent aesthetics can be extracted.

  Further, the wood to be used may be raw wood (undried raw wood) or dry wood. If wood is previously crushed into fine chips, the extraction efficiency of phenolic compounds can be increased.

The time for immersing the wood in the solvent to extract the compound P1 is not particularly limited, and can be extracted in about 1 hour to 10 days, for example.
The temperature of the solvent in which the wood is immersed for extracting the compound P1 is not particularly limited, and can be extracted at, for example, about 10 to 60 ° C.

  The preferred embodiment of the present invention has been described in detail above, but the present invention is not limited to the specific embodiment, and various modifications can be made within the scope of the present invention described in the claims. It can be changed.

  Next, the present invention will be described in detail by the following examples, but the present invention is not limited only to these examples.

Example 1
A cedar plate measuring 300 mm in length and 100 mm in width was used as a bottom plate, and a side plate matched with the bottom plate was prepared to assemble a formwork made of wood. A concrete colorant 13 containing a phenolic compound (compound P1) extracted from a cedar wood piece into an aqueous solvent is applied to the concrete placing surface of the bottom plate, and the water cement ratio is set to 50%. Portland cement (hereinafter referred to as N50) was cast and demolded at a material age of 3 days to prepare a specimen for a concrete member. The used N50 was kneaded until kneading was not observed after kneading. Along with the specimen, a cedar material of the same type as the cedar plate used for the bottom plate of the mold was prepared as a reference sample.

Next, using the surface that was in contact with the bottom plate of the mold as the measurement surface, color measurement was performed on the measurement surface of the specimen immediately after demolding. For the color measurement, a color difference meter (model number: CR-410, manufactured by Konica Minolta) was used. Further, the color change was evaluated by L ^* , a ^* , b ^{* of the} CIE 1976 color space. Table 1 shows the measurement results of the hues of the measurement surfaces of the uncolored N50 and the test body of this example immediately after demolding. Note that, in the test body of the present example, the hue varies depending on the measurement location, so Table 1 shows the average value of the measurement values at 12 locations on the measurement surface.

From the results shown in Table 1, it was confirmed that the lightness L ^* was decreased and b * was significantly increased on the measurement surface of the test body coated with the concrete colorant. As a result, it was confirmed that the measurement surface of the specimen was finished in yellowish gray.

  Next, cross-sectional observation near the measurement surface of the specimen was performed using a scanning electron microscope (SEM). FIG. 7 shows a cross-sectional photograph by SEM, and FIG. 8 shows the results of measurement of calcium element distribution and carbon element distribution in the vicinity of the measurement surface. As can be seen from FIG. 7, there was a difference in image density between the test piece inside the thickness of about 400 μm from the surface layer of the measurement surface and the test piece inside. Regarding the difference in light and shade, the element mapping results shown in FIG. 8 show that a large amount of carbon element is distributed on the surface layer of the measurement surface of the test body, and the amount of calcium element is small compared to the test body inside the surface layer. It can be seen that it is distributed. That is, the difference in light and shade in FIG. 8 is presumed to have been caused by the difference in carbon element concentration and calcium element concentration in the test specimen. Although calcium element is derived from cement, supply of carbon element (compound P1) from the concrete colorant is considered as a factor that causes a change in the carbon element concentration due to the thickness dimension from the surface layer of the measurement surface of the specimen. It is done. From these results, it was confirmed that the discoloration on the measurement surface of the test specimen was caused by a substance containing a large amount of carbon element. Further, in this example, the range from the measurement surface of the specimen to the inside of the thickness dimension of about 400 μm was colored.

  Next, a part was sampled from the colored portion in the vicinity of the measurement surface of the test body and the non-colored portion inside the test body to obtain a colored sample and a non-colored sample, respectively. Then, acid-alkaline aqueous solution extraction experiment was done with reference to the chemical substance test method of slag of JIS K0058-1 with respect to the colored sample and the non-colored sample. Specifically, each sample and an acid-alkali aqueous solution were mixed at a weight volume ratio of 1:10 and shaken for 6 hours. After extraction, the suspension was centrifuged at 2000 rpm for 10 minutes, and the supernatant was filtered through a 0.45 μm filter. Thereafter, the pH of the filtrate, the amount of total organic carbon (TOC) and the absorbance were measured using a commercially available pH electrode and TOC meter, and a spectroscopic analyzer (model number: U-2000, manufactured by Hitachi, Ltd.). It was measured.

  Moreover, acid-alkaline aqueous solution extraction experiment was done also with respect to the cedar board prepared as a reference sample with reference to the chemical substance test method of slag of JISK0058-1. At this time, the cedar plate was molded into a size of 20 mm long × 80 mm wide × 13 mm thick (hereinafter referred to as a cedar piece). As the acid-alkali aqueous solution, an aqueous solution prepared by mixing sulfuric acid and calcium hydroxide solution in pure water so that the pH was 4, 7, 9, 10, 11, 12 was used. Moreover, extraction of organic substances such as compound P1 from cedar pieces was performed by placing cedar pieces and 250 mL of acid-alkali aqueous solution in a polypropylene container with a cap and immersing them for one week. Since the cedar pieces floated in the acid-alkali aqueous solution during the immersion period, the polypropylene container was inverted every other day. After the immersion period, the extract was filtered through a 0.45 μm filter, and then the pH, TOC amount, and absorbance of the filtrate were measured by the same method as the acid-alkali aqueous solution extraction experiment on the colored and non-colored samples.

  In FIG. 9, the measurement result of the amount of TOC for every pH of a colored sample and a non-colored sample is shown. As shown in FIG. 9, it was confirmed that the colored sample contained about 5 times the TOC compared to the non-colored sample. This result is in agreement with the SEM measurement result of FIG. 7, and it can be estimated that the discoloration of the test specimen is due to the organic matter derived from cedar contained in the concrete colorant, that is, the compound P1. Focusing on the effect of the pH of the filtrate on the amount of TOC, although the amount of TOC was high when the pH was 11, there was no significant difference between the case where the pH was 7 and the case where it was 4. .

  After the acid / alkaline aqueous solution extraction experiment, when the pH of the solution obtained by filtering the colored sample and the non-colored sample was measured, it changed from pH 4 to pH 12.6, from pH 7 to pH 12.6, and from pH 12 to pH 12.7. It was found that the pH of the solution was increased by the influence of calcium hydroxide contained in the cement of the test specimen.

  Next, the color of the organic matter extracted from the cedar pieces into the acid-alkali aqueous solution was visually observed. As a result, it was confirmed that the brown color derived from the cedar was darker as it was immersed in the solution having a higher pH. Possible causes of the change in color shade due to pH are both the change in the color of the extracted substance itself and the increase in the concentration of the extracted substance. Therefore, by using a pH 12 extraction solution and adding a strong acid, the concentration of the solution was hardly changed, and only the pH was changed and the color of the solution was visually observed. As a result, the color of the solution lightened as the pH decreased. Since the total amount of the solution is hardly changed, the extracted substance shows a different color depending on each pH. Further, this color reaction was reversible, and when the pH was changed again from a low pH to a high pH, the color of the solution became darker. As a result, the colored portion of the test specimen contains about 5 times as much organic matter as the inside, and the degree of coloration of the solution extracted from the cedar pieces varies depending on the pH and is highly alkaline as in cement. As a result, it was confirmed that the color was darker.

  Then, the measurement result of the wavelength dependence of the light absorbency in the extraction solution of a cedar piece is shown in FIG. As shown in FIG. 10, the absorbance peak at a wavelength of 270 nm was confirmed in the solutions extracted at pH 4 and pH 7, but the absorbance peak at the same wavelength was small in the extracted solution at pH 12. This absorbance peak is unique to tannin, and it was confirmed that tannin was contained in the extracted solution of cedar pieces. Tannin has the property of browning in an alkaline environment, and this property has been confirmed by observation of the color of the extract. From the above, it can be said that tannin is one of the substances that discolor the specimen naturally. On the other hand, lignin contained in a large amount in wood shows a relatively dark brown color at any pH and has a great influence on the color of concrete after coloring. Therefore, it is considered that the surface of concrete can be discolored even with a small amount.

  As shown in Example 1, in addition to the measurement surface of the test body being colored, the unevenness pattern of summer eyes and winter eyes is formed on the measurement surface, so that the natural tone brought out from the test body is obtained. It is thought that aesthetics and warmth are enhanced.

(Example 2)
Using each of the concrete a blended as shown in Table 2 and the concrete b blended as shown in Table 3, two wall-type concrete members (hereinafter referred to as mock-ups a and b) having a length of 1800 mm × width of 1800 mm × thickness of 200 mm are used. Prepared body.

  As a mold used for placing mock-ups a and b, a cedar board similar to that used in Example 1 was used. Also, a concrete colorant containing compound P1 obtained by extraction from cedar into an aqueous solvent was prepared in advance, and this colorant was applied to the bottom plate made of cedar before placing concrete. As a result, the compound P1 was transferred to the measurement surface of each mockup together with the unevenness of the cedar wood pattern (wood grain), and a beautiful texture like wood was expressed. In addition, after demolding, a commercially available clearing agent was applied to the colored surface (measurement surface) to form a transparent film and protect the color of the colored surface.

FIG. 11 and FIG. 12 show the results of measuring changes over time in the lightness L ^* and b ^* of the colored surfaces of mockups a and b. The brightness L ^* and b ^* were measured by the same method as in Example 1. In addition, it measured in three different places in the height direction of each mockup, and plotted the average value.

Mock-up a is made of high-strength concrete having a water cement ratio of 31% using low heat Portland cement, and its lightness L ^* is about 60, which is almost constant during the measurement period.
On the other hand, mock-up b showed lightness L ^{* of} about 52 until the 10th day after demolding, and lightness L ^{* of} about 60 on the 30th day after demolding. As a factor of this brightness change, the water retention effect of the shrinkage reducing agent contained in the concrete member constituting the mock-up b can be mentioned. It is conceivable that rapid drying immediately after demolding was prevented by this water retention effect.

As for the brightness b ^* , as shown in FIG. 12, in mock-up a using concrete with a low water-cement ratio, b ^* increased after demolding and converged to a value of about 4. Further, in mock-up b using medium heat Portland cement, b ^* was a relatively small value.
Since b ^* greatly affects the color and texture of the concrete member, it is important to consider the type of concrete used, the water cement ratio, the sand cement ratio, and the change in b ^* after drying.

(Example 3)
The mockup of Example 2 was added by changing the cedar board used as a mold in the production of the mockup b of Example 2 to a veneer plywood, a larch plywood, and a cedar board whose surface was covered with a resin film. Mock-ups were prepared in the same manner as b. At this time, before placing the concrete, a concrete colorant containing the compound P1 obtained by extracting the same kind of wood as the used plate material into an aqueous solvent was applied in advance. Thereby, compound P1 was transferred to the measurement surface of each mock-up together with the unevenness of the wood pattern (grain) of each plate material, and a beautiful texture like wood was expressed.

The lightness L ^* and b ^* of the colored surface of each mockup coated with the compound P1 derived from each plate material was measured. The results are shown in FIGS. In these figures, the measured value at the time of demolding and the measured value in the state of being exposed outdoors until the dry material age of 22 days are shown.

  13 and 14, “Sugi real” is a case where a cedar board is used as a mold, “Veneer plywood” is a case where a veneer plywood is used as a form, and “Larch plywood” is a larch plywood as a form. "Film" represents the case where a cedar board whose surface is covered with a resin film is used as a mold.

In a mockup ("film" in the figure) produced using a bottom plate whose surface is coated with a resin film, the value of b ^* is lower at the time of demolding than other mockups. As a cause of this, on the other mockup measurement surface, the pigment such as compound P1 transferred from the plate material itself constituting the formwork at the time of placing concrete is reflected in the b ^* value, whereas the mockup It is conceivable that the (film) measurement surface is colored only by a small amount of the concrete colorant applied to the film surface.

On the measurement surface of each mock-up, the lightness L ^* increased and b ^* tended to decrease with outdoor exposure for 22 days. This tendency was observed not only for cedar boards but also for veneer plywood and larch plywood. The reason for this decrease in b ^* is considered to be that the colorant was washed away by wind or rain or the colorant was decomposed because the measurement surface was not covered and protected with a clearing agent during outdoor exposure.

Example 4
Similar results were obtained when ordinary Portland cement, early-strength Portland cement and blast furnace cement were used in place of the medium heat Portland cement and low heat Portland cement used in Examples 2 and 3.

(Example 5)
A form using cedar wood was prepared on the surface where the concrete to be placed touches. Moreover, 1 mass%, 5 mass%, 10 mass% tannic acid aqueous solution and 10 mass%, 50 mass%, and 100 mass% lignin aqueous solution or lignin liquid were prepared as concrete colorants, respectively. The tannic acid and lignin used here are commercially available products that can be purchased as reagents. Subsequently, tannic acid aqueous solution and lignin aqueous solution of each concentration were respectively applied to the surface where the mold and the concrete contacted, and ordinary concrete was cast. Each concrete was demolded at a dry material age of 1 day to obtain test bodies B to G. Further, a test specimen A prepared by placing ordinary concrete without applying any concrete colorant of tannic acid aqueous solution and lignin aqueous solution to the mold and demolding at a dry material age of 1 day was prepared.

In each of the test bodies A to G, the concrete surface layer portion in contact with the bottom surface of the formwork is divided into six sections a to f as shown in FIG. 15, and the center portion of each section (the position of the X mark in FIG. 15). ) L ^* , a ^* , b ^* . Table 4 shows the average values of the measured values at the center of the sections a to f for each of L ^* , a ^* , and b ^* .

As shown in Table 4, it can be seen that the value of b ^* of the test specimens B to G is larger than that of the test specimen A, and the tannin or lignin colored the natural tone.

(Example 6)
As a concrete sample before coloring, a disc-shaped white plate made of ordinary Portland cement and having a diameter of 30 centimeters was prepared by a conventional method. When this white plate was coated with a tannic acid aqueous solution containing tannic acid at a concentration of 5 to 10% by weight and dried, the coated portion could be colored in a wood-like brown color. Moreover, when tannic acid was changed to gallic acid and the same test was conducted, it was possible to color the wood-like brown with a texture different from that of tannic acid.

(Reference experiment)
When iron sulfate was dissolved in the tannic acid aqueous solution, it was confirmed that the color of the tannic acid aqueous solution changed from light brown to dark brown. Similarly, when iron sulfate was dissolved in a gallic acid aqueous solution, it was recognized that the color of the gallic acid aqueous solution changed from light brown to dark brown. This color change is considered to be due to the formation of a complex between each compound and / or its hydrolyzate and iron ions in an aqueous solution.

2 ... decorative concrete, 3 ... decorative concrete, 4 ... concrete member (concrete), 4a ... decorative face, 4d ... colored layer, 10 ... formwork, 12 ... concrete, 12p ... concrete surface, 13 ... concrete colorant, 14 ... Formwork with phase shape (wooden formwork)

Claims (8)

It is represented by the following general formula (P1) on the surface of concrete based on one or more cements selected from the group consisting of ordinary Portland cement, moderately hot Portland cement, low heat Portland cement, early-strength Portland cement and blast furnace cement. A concrete member characterized by having a concrete colorant containing a phenolic compound attached thereto.
[Wherein, R represents an n-valent organic group, m represents an integer of 1 to 5, and n represents an integer of 1 or more. ]   The concrete member according to claim 1, wherein the concrete includes crushed lime sand.   The concrete member according to claim 1 or 2, wherein the phenolic compound is lignin or tannin.   The concrete member according to claim 1, wherein the phenolic compound is gallic acid. The concrete member according to any one of claims 1 to 4 , wherein unevenness of a wood pattern is formed on a colored surface of the concrete member. By dipping the wood in an aqueous solvent, a step of extracting a phenolic compound represented by the following general formula (P1),
The concrete surface containing the phenolic compound as a base material of one or more cements selected from the group consisting of ordinary Portland cement, moderately hot Portland cement, low heat Portland cement, early strength Portland cement and blast furnace cement method for producing a concrete member you characterized by having the steps of attaching to.
[Wherein, R represents an n-valent organic group, m represents an integer of 1 to 5, and n represents an integer of 1 or more. ] The method for producing a concrete member according to claim 6 , wherein the phenolic compound is extracted by immersing the wood in an aqueous solvent having a pH of 4 or more. The method for producing a concrete member according to claim 6 or 7 , wherein the wood is cedar, lauan, or larch.