JP2021084851A - Hardened cement body and method of producing the same - Google Patents

Abstract

To provide a hardened cement body in which a latent image is formed.SOLUTION: A hardened cement body having a latent image, comprising at least one display surface on the surface of the hardened cement body, at least one inclined plane that is inclined in the range of from 0 to 90 degrees relative to the display surface, and a plurality of information display portions provided on the display surface so that the inclined plane(s) faces (or face) specific direction(s), wherein pieces of information are attached to the inclined surfaces of the information display portions, so that the information display portions display information in specific direction(s).SELECTED DRAWING: Figure 1

Description

The present invention relates to a hardened cement product on which a latent image is formed and a method for producing the same.

Conventionally, latent image processing has been used as an anti-counterfeiting measure for 500-yen coins, game coins, and other anti-counterfeiting measures. For example, Patent Document 1 discloses a technique for directly applying anti-counterfeiting measures to a character of a brand logo formed on a product itself or a figure such as a trademark indicating a brand or a manufacturer. In this technique, a character or figure is formed in a bulk body, and then the character or figure is heated. Further, a mold having any shape of a predetermined grid, slit, protrusion, hole, or latent image is pressed against a character or figure to press the grid, slit, protrusion, hole, or latent image. , Transfer to at least part of a character or figure. After transfer, the cooling and pressing are released to remove the mold from the letter or figure, and the letter or figure is cooled or cast to form at least a portion of the letter or figure with a given lattice, slit, protrusion, hole. , Or any one or more of the latent images. This bulk body is provided for wristwatch exterior parts or movements, jewelery, tags, or fasteners.

Further, as a latent image processing technique, a machining technique by cutting has been proposed. For example, in Non-Patent Document 1, a system for realizing latent image processing is developed using a 5-axis machining center, and equipment, procedures, and problems necessary for latent image processing by cutting are carried out through the production of processing samples. Has been clarified.

Republished Patent WO2015 / 049913 Gazette

"Efforts to realize latent image processing by cutting" Yamamotodori, Bulletin of Oita National College of Technology No. 55, November 2018

The above-mentioned latent image processing technique has never been applied to a hardened cement product. If it becomes possible to process a latent image on a hardened cement body, it can be used for various purposes, and is expected to be used for advertisements and road signs.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a hardened cement product in which a latent image is formed.

(1) In order to achieve the above object, the present invention has taken the following measures. That is, the hardened cement body of the present invention is a hardened cement body on which a latent image is applied, and has at least one display surface provided on the surface of the hardened cement body and 0 to 90 degrees to the display surface. Each information display unit includes a plurality of information display units having at least one inclined surface inclined within a degree range and provided on the display surface so that the inclined surface faces a specific direction. The plurality of information display units display information in a specific direction by attaching information components to the inclined surfaces of the above. As a result, information can be latently imaged in each direction in which the inclined surface is facing.

(2) Further, in the hardened cement product of the present invention, the information display portion is characterized by having a three-dimensional shape of either a cone or a polygonal weight. As a result, information can be latently imaged in each direction in which the inclined surface is facing.

(3) Further, in the hardened cement product of the present invention, the information display unit is characterized in that the cross section is formed in a serrated shape by a plurality of parallel grooves provided on the display surface. As a result, information can be latently imaged in the direction perpendicular to the grooves provided in parallel.

(4) Further, in the hardened cement product of the present invention, the distance between the grooves is 0.1 mm or more. This makes it possible to prevent each groove from collapsing during processing.

(5) Further, in the cement cured product of the present invention, the information display portion is formed by vertically laminating a solidified product solidified by injecting an aqueous curing agent onto a powdery hydraulic composition. It is characterized by that. As a result, even if the shape of the information display unit is complicated, it is possible to easily form a hardened cement body having a latent image.

(6) Further, in the hardened cement product of the present invention, the information display unit fills a mold in which the three-dimensional shape of the information display unit is formed in advance with cement paste or mortar in which an aggregate is mixed with cement. It is characterized in that it is formed by removing the frame after curing. This makes it possible to easily form a hardened cement body having a latent image.

(7) Further, in the hardened cement product of the present invention, the maximum particle size of the aggregate is not more than the minimum width of the information display unit. This makes it possible to fill the formwork with cement paste or mortar without creating space in the details inside the formwork.

(8) Further, in the hardened cement product of the present invention, the information display portion is characterized in that it is formed by cutting a cement obtained by mixing an aggregate with the cement and hardening the cement. This makes it possible to perform latent image processing on a large-sized hardened cement body.

(9) Further, in the hardened cement product of the present invention, the maximum particle size of the aggregate is 5 mm or less. This makes it possible to prevent peeling of the interface between the aggregate and the paste by cutting.

(10) Further, the method for producing a hardened cement product of the present invention is a method for producing a hardened cement product having a latent image, the step of providing at least one display surface on the surface of the hardened cement body, and the above-mentioned. A plurality of concave or convex information display units are provided on the display surface so that at least one inclined surface that is inclined within a range of 0 to 90 degrees with respect to the display surface is provided so that the inclined surface faces a specific direction. It is characterized by including a step of providing the above. As a result, it is possible to manufacture a hardened cement product in which information is latently imaged in each direction in which the inclined surface is facing.

According to the present invention, it is possible to provide a cement cured product having a latent image. As a result, it becomes possible to provide supplementary information on road signs and information using a wall surface made of cement paste or mortar.

It is a schematic diagram of the cement hardened body which performed the latent image processing which is this embodiment. It is a front view of the cement hardened body which performed the latent image processing which is this embodiment. It is the figure which looked at the cement hardened body which performed latent image processing of this embodiment from the diagonally upper right. It is the figure which looked at the cement hardened body which performed latent image processing of this embodiment from the diagonally upper left. It is a partially enlarged view of the cement hardened body which performed the latent image processing which is this embodiment. It is a flow which shows the procedure of making the cement hardened body which gave a latent image. It is a figure which shows the state which converted into 3D data for output. It is a figure which shows the outline of the procedure for manufacturing a cement hardened body by laminating with an additional manufacturing apparatus. It is a figure which shows an example of the shape of the information display part. It is a figure which shows an example of the shape of the information display part.

Focusing on applying the latent image processing technology to the hardened cement body, the present inventors formed a plurality of inclined surfaces on the surface of the hardened cement body and attached information to the inclined surfaces to form the hardened cement body. , Found to form a latent image, and came to the present invention.

That is, the hardened cement body of the present invention is a hardened cement body on which a latent image is applied, and is 0 to 90 degrees with respect to at least one display surface provided on the surface of the hardened cement body and the display surface. Each information display unit includes a plurality of information display units having at least one inclined surface inclined within a degree range and provided on the display surface so that the inclined surface faces a specific direction. The plurality of information display units display information in a specific direction by attaching information components to the inclined surfaces of the above. As a result, the present inventors have made it possible to make the information latent in each direction in which the inclined surface is facing in the hardened cement body. Hereinafter, the present embodiment will be described with reference to the drawings.

FIG. 1 is a schematic view of a hardened cement product according to the present embodiment. FIG. 2A is a view looking down on the cement hardened body according to the present embodiment from a direction parallel to the groove, and FIG. 2B shows the cement hardened body according to the present embodiment on the right with respect to the state shown in FIG. 2A. It is a view seen from diagonally above, and FIG. 2C is a view of the cement hardened body according to this embodiment seen from diagonally above left with respect to the state shown in FIG. 2A. In the present embodiment, as shown in FIG. 1, the cement hardened body 100 to which two latent images (“Pacific” and the mark) are applied will be described, but the present invention is not limited thereto. For example, the latent image may be formed in only one direction, or the latent image may be formed in three or more directions.

The cement hardened body 100 according to the present embodiment has at least one display surface 3 provided on the surface of the cement hardened body body and at least one inclined surface that is inclined within a range of 0 to 90 degrees with respect to the display surface. It is provided with a plurality of information display units 5 provided on the display surface so that the inclined surface faces a specific direction. By attaching information components to the inclined surfaces of each information display unit 5, a plurality of information display units 5 display information in a specific direction. Further, the inclination angle of the inclined surface of each information display unit 5 is preferably 10 degrees to 80 degrees, more preferably 20 degrees to 70 degrees so that a plurality of latent images can be formed. By providing the plurality of inclined surfaces in this way, a plurality of latent images can be formed. As a result, another latent image can be seen when viewed from different directions.

In the cement hardened body 100 according to the present embodiment shown in FIGS. 1 and 2A to 2D, a plurality of information display units 5 are provided on the display surface 3. In the cement hardened body 100 according to the present embodiment, the information display unit 5 is formed by providing a plurality of parallel grooves from the bottom to the top with respect to the front view of FIG. 2A, and each information display unit 5 is formed. Has two inclined surfaces and has a triangular cross section. With respect to the two inclined surfaces of each information display unit 5 formed in this way, for example, an inclined surface is formed so that the inclined surface of the portion where characters and marks are to be formed has an inclined angle different from other inclined surfaces. Thereby, a latent image of characters and marks can be formed. The shape of the cross section is not limited to a triangular shape, and may be another serrated shape, a rectangular shape, or a wavy shape. Further, each information display unit 5 itself may have a three-dimensional shape such as a cone or a polygonal weight instead of a plurality of parallel grooves, and as shown in FIGS. 6A and 6B, the information display unit 5 itself may have a three-dimensional shape with respect to the display surface 3. It may be dented or convex. Further, the inclined surface does not have to be flat and may be spherical.

In the information display unit 5 of the cement hardened body 100, for example, when it is desired to form an image (latent image) so that the characters "Pacific" can be seen when viewed from diagonally above to the right as shown in FIG. 2B, the information display unit of each information display unit By making the inclination angle of the inclination surface of the information display unit of the portion where the latent image of the character is to be formed larger or smaller than the inclination angle of the other information display units on the inclination surface on the right side with respect to the front view of FIG. 2A. A latent image of the letters "Pacific" can be formed.

Further, in the information display unit 5 of the cement hardened body 100, for example, when it is desired to form an image (latent image) so that the mark can be seen when viewed from diagonally above left as shown in FIG. 2C, the figure of each information display unit is shown. By making the inclination angle of the inclination surface of the information display portion of the position where the latent image of the mark is to be formed larger or smaller than the inclination angle of other information display portions on the inclination surface on the left side of the front view of 2A, the mark is made. Can form a latent image of.

In this way, among the plurality of information display units 5, the inclined surface of some of the information display units 5 is provided with an inclination angle different from that of the other information display units, so that a latent image of characters, patterns, etc. Can be formed. Further, it is also possible to add color to the inclined surface of each information display unit forming the latent image.

The hardened cement bodies 100 shown in FIGS. 1 and 2A to 2D are 10 cm × 10 cm × 1.0 cm, but can be formed as long as they are 5 cm × 5 cm × 0.5 cm or more. Further, the size of the pitch of the unevenness formed on the cement hardened body 100 of the present embodiment is 2.0 mm, but it can be formed as long as it is 1.0 mm or more.

(Manufacturing method of hardened cement with latent image processing)
A method for producing a hardened cement product according to the present embodiment will be described. The manufacturing method includes a manufacturing method using a laminated three-dimensional modeling device (additional manufacturing device / 3D printer), a manufacturing method using a mold, and a manufacturing method using cutting. Each will be described below.

(1) Manufacturing Method Using Laminated Three-Dimensional Modeling Equipment (Additional Manufacturing Equipment / 3D Printer) FIG. 3 is a flow showing a procedure for producing a cement cured product having a latent image. First, 3D model data of the hardened cement body processed with a latent image is created (step S1). Next, the created 3D model data is converted into output 3D data (step S2).

4 (a) and 4 (b) are views showing a state in which two types of latent images are converted into 3D data for output of a processed cement cured product. The converted output 3D data is divided into a large number of horizontal planes (step S3). Next, the shapes of the divided horizontal planes are sequentially laminated using an addition manufacturing apparatus (step S4).

The work of step S4 will be described in detail. FIG. 5 is a diagram showing an outline of a procedure for manufacturing a cured product by laminating with an additional manufacturing apparatus. Here, an inorganic powder that can be used in a laminated three-dimensional modeling apparatus is used as the material. The details of the material of the inorganic powder are prepared by mixing the material of the hydraulic composition described later by machine or by hand, or by mixing and crushing with a crusher.

First, the powder feeder 21 flattens the inorganic powder placed on the table (FIG. 5 (a)). Next, based on the data of the shape of the divided horizontal plane, the aqueous curing agent is sprayed from the head 25 to solidify the powder (FIG. 5 (b)). When the work of FIGS. 5 (a) and 5 (b) is completed, the table 27 is further lowered, the powder supply tank 29 is further raised, and the inorganic powder is laid on the table 27 (FIG. 5 (c)). Latent image processing is performed by repeating the operations of FIGS. 5 (a) to 5 (c) and removing excess powder of the modeled object 31 formed by laminating the divided horizontal plane shapes. A hardened cement product can be produced (FIG. 5 (d)). As described above, in the manufacturing method using the laminated three-dimensional modeling apparatus, since the cement hardened body is formed based on the 3D data as described above, it is possible to produce a complicated shape.

The produced cement hardened body may be cured in the air alone, in a method of subsequently curing in water after being cured in the air, or cured with a surface impregnating agent. Among these, aerial curing alone is preferable from the viewpoint of early strength development and suppression of water vapor generated during the production of the hardened cement according to the present embodiment. Although the details of the material will be described later, the temperature of the aerial curing is preferably 10 to 100 ° C. from the viewpoint of increasing the strength by the calcium aluminate, the quick-hardening cement, and the polyvinyl alcohol contained in the hydraulic composition. Further, 30 to 80 ° C. is more preferable. The relative humidity of the air curing is preferably 10 to 90%, more preferably 15 to 80%, and even more preferably 20 to 60% from the viewpoint of sufficient strength development and production efficiency. Further, the aerial curing period is preferably 1 hour to 1 week, more preferably 2 hours to 5 days, and further preferably 3 hours to 4 days from the viewpoint of sufficient strength development and production efficiency.

(Hydraulic composition)
If the hydraulic composition used in the present embodiment is too soft, the modeled product will collapse during processing, so that a certain level of strength is required. A hydraulic composition for subjecting a hardened cement body to a latent image using a laminated three-dimensional modeling apparatus will be described.

The water-curable composition further contains 28 to 45 parts by mass of water and sand with respect to 100 parts by mass of the total mass of the composite binder containing 2 to 12 parts by mass of polyvinyl alcohol with respect to 100 parts of the inorganic binder. ..

The inorganic binder is a binder containing at least one selected from calcium aluminates as an essential component, and further containing gypsum, quick-hardening cement, and the like as optional components. Among the inorganic binders, calcium aluminate is preferable to be used as an inorganic binder because of its high strength-developing property, and it is more preferable to use amorphous calcium aluminate. In particular, amorphous calcium aluminate is produced by quenching after melting the raw material, so that it does not have a substantially crystal structure, and its vitrification rate is usually 80% or more, and the vitrification rate is high. The higher the value, the higher the early strength development, so the vitrification rate is preferably 90% or more.

In order to further improve the early strength development, the inorganic binder may contain gypsum as an optional component. Examples of gypsum include one or more selected from anhydrous gypsum, hemihydrate gypsum, and dihydrate gypsum, but hemihydrate gypsum is preferable because it has a higher early strength development.

Further, in order to further improve the early strength development, the inorganic binder may contain quick-hardening cement (also referred to as ultrafast-hardening cement) as an optional component, and the quick-hardening cement is measured in accordance with JIS R 5210. Fast-hardening cement (ultra-fast-hardening cement) or water-stopping cement, which is hardened within 30 minutes, is preferable.

Cement may be included as another component in the inorganic binder. Cement is preferably within 3 hours and 30 minutes as measured in accordance with JIS R 5210 because it has high early strength development 3 hours after molding, and more preferably within 1 hour. Examples of cement include one or more types from ordinary Portland cement, early-strength Portland cement, moderate heat Portland cement, low heat Portland cement, white Portland cement, eco-cement, blast furnace cement, fly ash cement, and cement clinker powder. The content of calcium silicate in the cement is preferably 25% by mass or more, with 10% by mass of the entire cement. When the content is 25% by mass or more, the strength development after 1 day of age is high, and when long-term strength development is required, the content is preferably 45% by mass or more.

The cement content in the inorganic binder is preferably 0 to 50% by mass, more preferably 0 to 30% by mass, and 0 to 20%, with the entire inorganic binder as 100% by mass, in order to improve the early strength development. Is more preferable.

The composite binder is a binder containing 2 to 12 parts by mass of polyvinyl alcohol with respect to the inorganic binder 100. If the compounding ratio of polyvinyl alcohol is less than 2 parts by mass, the effect of improving the strength is low, and if it exceeds 12 parts by mass, deformation or cracking occurs due to shrinkage of the molded product depending on the shape, and a complicated shape may be manufactured. It may not be possible. The mixing ratio of polyvinyl alcohol is more preferably 2 to 10 parts by mass, still more preferably 3 to 9 parts by mass with respect to 100 parts by mass of the inorganic binder.

The average particle size (median diameter, D50) of polyvinyl alcohol is preferably 150 μm or less, more preferably 90 μm or less, and further preferably 10 to 75 μm or less because high strength can be obtained. The content of polyvinyl alcohol particles larger than 94 μm is preferably 90% by mass or less, more preferably 45% by mass or less, and further preferably 30% by mass or less. The content of polyvinyl alcohol particles larger than 77 μm is preferably 90% by mass or less, more preferably 60% by mass or less, and further preferably 50% by mass or less.

The hydraulic composition is a composition containing 28 to 45 parts by mass of water and sand with respect to a total of 100 parts by mass of the composite binder. When the mixing ratio of water is within the above range, the strength development can be ensured. The mixing ratio of sand is preferably 100 to 600 parts by mass, more preferably 150 to 500 parts by mass, and further preferably 200 to 400 parts by mass with respect to 100 parts by mass of the composite binder. If the blending ratio of sand is within this range, the strength development can be similarly ensured.

In order to prepare for the work (depowder) of removing the uncured powder of the hydraulic composition remaining after molding as another component in the hydraulic composition from the molded product, a total of 100 composite binders are added. With respect to parts by mass, hydrophobic fumed silica can be contained as an arbitrary component in an amount of 0.1 to 2 parts by mass, more preferably 0.5 to 1.5 parts by mass.

(2) Manufacturing method using a mold Next, a manufacturing method using a mold will be described. First, a mold that has been subjected to latent image processing in advance is prepared (step P1). Next, a cement paste prepared by mixing cement with water, or a mortar prepared by mixing cement with aggregate such as sand and water is filled in a mold and cured (step P2). After the mortar has hardened, the frame is removed (step P3). In the case of a mold having a complicated shape such as latent image processing, it is more preferable to use a mold formed by using the above-mentioned laminated three-dimensional modeling apparatus.

When a hardened cement product is manufactured from a mold, if the amount of air in the cement paste or mortar to be filled is large, air bubbles may be generated after the hardening and the surface irregularities may be deformed. Therefore, when kneading the cement paste or mortar, it is preferable to mix an antifoaming agent or the like to reduce the amount of air.

Also, when filling the mold with cement paste or mortar, the maximum grain shape of the aggregate is the uneven portion of the cement hardened body to be formed so that the cement paste or mortar is filled without creating space in the mold. It is preferably below the minimum surface. More preferably, it is preferably two-thirds or less of the minimum width, and further preferably one-half or less of the minimum width.

In addition, materials with similar diameters are used so that bleeding water does not remain on the uneven parts of the cement hardened body to be formed, and the material has appropriate viscosity and material separation resistance, and the amount of bleeding is small. It is preferable to have.

(3) Manufacturing method by cutting First, a hardened mortar is prepared. Based on the created 3D model data, the hardened mortar is cut. The cutting method includes a cutting method using a machine and a water jet method. In the cutting method using a machine, the cured mortar is cut using a cutting machine, so that it is possible to perform latent image processing on a large-sized cured mortar. In the cutting method using the water jet method, it is possible to perform latent image processing by cutting the mortar using the force of high-pressure water that is compressed and injected by a high-pressure pump. When the water jet method is used, it is possible to suppress vibrations on the hardened mortar compared to the cutting method using a machine, so latent image processing can be performed while minimizing the effect on the hardened mortar. It can be carried out.

When processing by cutting, there is a risk of peeling at the interface between the aggregate and the paste, so it is preferable to use one having similar strengths to the aggregate and the paste. Further, since there is a risk of peeling at the interface between the aggregate and the paste, the maximum particle size of the aggregate is preferably as small as 5 mm or less, more preferably 2 mm or less, and further preferably 1 mm or less. Is more preferable. Further, when processing by cutting, it is preferable to use a square aggregate.

As described above, a latent image is formed on the hardened cement body by providing a plurality of inclined surfaces on the surface of the hardened cement body and giving some inclined surfaces different from the other inclined surfaces. can do. As a result, it becomes possible to provide supplementary information on road signs and information using a wall surface made of mortar. For example, in a curve of a roadway, the occurrence of an accident can be suppressed or prevented by forming a latent image such as a curve or a warning mark on the road surface or a wall surface in the direction in which the vehicle is traveling. It is also possible to add color to a plurality of inclined surfaces on the surface of the hardened cement body forming a latent image.

100 Cement hardened body on which a latent image is formed 3 Display surface 5 Information display unit 21 Powder feeder 23 Roller 25 Head 27 Table 29 Powder supply tank 31 Modeled object

Claims (10)

It is a hardened cement with a latent image.
At least one display surface provided on the surface of the cement hardened body,
A plurality of information display units having at least one inclined surface that is inclined within a range of 0 to 90 degrees with respect to the display surface, and provided on the display surface so that the inclined surface faces a specific direction. And with
A cement hardened body, characterized in that the plurality of information display units display information in a specific direction by attaching information components to the inclined surfaces of the respective information display units. The hardened cement product according to claim 1, wherein the information display unit has a three-dimensional shape of either a cone or a polygonal weight. The hardened cement according to claim 1 or 2, wherein the information display unit has a serrated cross section formed by a plurality of parallel grooves provided on the display surface. The hardened cement product according to claim 3, wherein the distance between the grooves is 0.1 mm or more. Claims 1 to 4 are characterized in that the information display unit is formed by vertically laminating a solidified product solidified by injecting an aqueous curing agent onto a powdery hydraulic composition. The cement hardened body according to any one of. The information display unit is formed by filling a mold in which the three-dimensional shape of the information display unit is formed in advance with mortar in which cement is mixed with an aggregate, curing the mortar, and then removing the frame. The hardened cement according to any one of claims 1 to 4. The hardened cement according to claim 6, wherein the maximum particle size of the aggregate is equal to or less than the minimum width of the information display unit. The hardened cement according to any one of claims 1 to 4, wherein the information display unit is formed by cutting a cement obtained by mixing aggregate with cement and hardening the cement. The hardened cement according to claim 8, wherein the maximum particle size of the aggregate is 5 mm or less. It is a method of manufacturing a hardened cement with a latent image.
The process of providing at least one display surface on the surface of the cement hardened body,
At least one inclined surface that is inclined within a range of 0 to 90 degrees with respect to the display surface is provided, and a plurality of concave or convex information displays on the display surface so that the inclined surface faces a specific direction. A method for producing a hardened cement product, which comprises a step of providing a portion and a step of providing a portion.

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