JPH0752135A - Production of roof tile - Google Patents

Abstract

PURPOSE:To produce a roof tile with good productivity by a method wherein broken stone or sand is scattered over the surface of a receiving mold and an uncured cementitious press molded object is placed thereon to be aged and cured as it is. CONSTITUTION:Broken stone or sand 6 is scattered over the molding surface 5 of a receiving mold 5 and an uncured cementitious press molded object 3 is placed thereon. At this time, a part of broken stone or sand 6 is relatively bitten into the surface layer of the cementitious press molded object by the gravity of the cementitious press molded object and the remainder thereof becomes an exposed state. The surface of the cementitious press molded object is floated from the molding surface 51 of the receiving mold 5 by the exposed part of the broken stone or sand 6. Next, the cementitious press molded object is fed into an ageing oven along with the receiving mold in this state to be aged and cured. By this constitution, a roof tile having broken stone or sand on its surface can be produced with good productivity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a roof tile having crushed stone or sand on its surface.

[0002]

2. Description of the Related Art Conventionally, as a method for producing an inorganic product having crushed stone or sand on its surface, for example, Japanese Patent Publication No. 61.5
As described in Japanese Patent No. 1966, before the substrate is cured and cured, the width and thickness of the substrate are adjusted by a forming roll and a forming die, colored sand is scattered on the surface of the substrate, and the substrate is transferred according to the movement of the substrate to be transferred. By pressurizing while running,
A method has been proposed in which colored sand is embedded in a substrate, an emulsion resin solution is applied to the surface of the substrate in which the colored sand is embedded, and then the substrate is cured.

[0003]

However, in this method, the width and thickness of the substrate are adjusted by the forming roll and the forming die, and the pressure is applied during the running while the transfer is performed according to the movement of the transferred substrate. However, since it is necessary to embed the colored sand in the substrate, there is a problem that the process of applying the emulsion resin solution is complicated. In addition, in the above-mentioned conventional method, it is almost impossible to mold a product having a three-dimensional shape, and in the press molding method which is a manufacturing method capable of molding a roof tile having a three-dimensional shape, the press molding is usually performed. The uncured cement-based press-molded product that has been press-molded by the mold so that the product surface is the lower surface is placed on a receiving mold that has a mold surface that matches the product shape as it is and transferred to the curing cabinet. Then cure and cure. Therefore, in the case of the press molding method, there is usually no step in which the surface of the product faces the upper surface, and therefore the above method cannot be adopted.

The present invention solves the above-mentioned conventional problems, and the product surface adopted as a manufacturing method capable of forming a roof tile having a three-dimensional shape of the roof tile without going through complicated steps. The object of the present invention is to provide a method capable of producing a roof tile having crushed stones or sand on the surface with high productivity even in the press molding method in which the step of facing the upper surface is not required.

[0005]

DISCLOSURE OF THE INVENTION According to the present invention, crushed stone or sand is sprinkled on the surface of a receiving mold, and the uncured cement-based press-molded article is placed with the upper surface facing downward, and then, as it is. This is a method for manufacturing roof tiles that can be cured and cured.

The receiving mold used in the present invention receives an uncured cement-based press molded product and conveys it as it is.
It refers to the mold used for manufacturing roof tiles by curing and curing. On the surface of the receiving mold, a mold surface that matches the surface shape of the uncured cement-based press molded product, that is, the outer surface shape of the roof tile to be manufactured is formed.

As the crushed stone or sand used in the present invention, those having an acute angle portion are preferably used. When crushed stone or sand with sharp corners is used, crushed stone or sand is sprayed on the mold surface of the receiving mold, and when the uncured cement-based press molded body is placed on it, the cement-based press molded body Part of the crushed stone or sand is likely to bite into the surface layer of.

In the present invention, as a raw material for molding the cement-based press-molded product, one comprising cement, water, reinforcing fibers optionally added, an inorganic filler, a thickener and the like is used. As the cement, for example, ordinary Portland cement, alumina cement, acid-resistant cement,
Examples include refractory cement.

The amount of water added to the cement is preferably 15 to 100 parts by weight, more preferably 20 to 60 parts by weight, based on 100 parts by weight of cement. Addition amount is 1
If it is less than 5 parts by weight, it becomes difficult to cure the uncured cement-based press molded article, and it becomes difficult for crushed stones or sand to penetrate into the surface layer of the cement-based press molded article in the uncured state. When it exceeds 100 parts by weight, the mechanical strength of the obtained roof tile becomes low and crushed stone or sand tends to be completely embedded in the surface layer of the uncured cement-based press-molded product.

Reinforcing fibers are added to the resulting cement-based pressed roof tile to improve the strength and prevent cracks.
Examples thereof include vinylon fiber, polypropylene fiber, aramid fiber, acrylic fiber, rayon, carbon fiber, glass fiber, potassium titanate fiber, alumina fiber, steel fiber and slag wool.

The fiber length of the reinforcing fiber is preferably 1 to 15 mm. If the fiber length is shorter than 1 mm, it will re-aggregate during mixing,
The strength of the roof tile obtained by forming fiber balls is not improved, and conversely, when it is longer than 15 mm, the dispersibility in the raw material for molding tends to decrease. Fiber diameter of reinforcing fiber is 1
˜500 μm is preferred. If the fiber diameter is smaller than 1 μm or larger than 500 μm, the reinforcing effect of the obtained roof tile tends to be small.

The amount of reinforcing fiber added is preferably 10 parts by weight or less with respect to 100 parts by weight of cement. Addition amount is 10
If the amount is more than the amount by weight, the dispersibility in the raw material for molding tends to decrease.

The inorganic filler is added to reduce shrinkage at the time of curing, improve the fluidity of the slurry, densify the cell, etc.
Examples thereof include silica sand, silica stone powder, fly ash, slag, silica fume, mica, talc, wollastonite, calcium carbonate, and aerosil.

The average particle size of the inorganic filler is 0.0
1-1 mm is preferable. If the average particle size is smaller than 0.01 mm, the viscosity will increase due to an increase in the amount of adsorbed water and the workability will be reduced, while if it is larger than 1 mm, the strength of the roof tile obtained will tend to be reduced.

The amount of the inorganic filler added is 100
It is preferably 100 parts by weight or less with respect to parts by weight. If the addition amount exceeds 100 parts by weight, the strength of the obtained roof tile tends to be lowered.

Examples of the thickener include methyl cellulose, polyacrylamide, polyvinyl alcohol, methyl cellulose and the like.

The steps of the method for manufacturing a roof tile according to the present invention will be described below with reference to the drawings. In the method for manufacturing a roof tile of the present invention, a dewatering press mold 1 as shown in FIGS. 1 (a) to 1 (c) is used. The dewatering press mold 1 includes a lower mold 11 and an upper mold 12, and a cavity 13 corresponding to the outer surface shape of the roof tile to be molded is formed between the mold surfaces of the lower mold 11 and the upper mold 12.
The upper mold 12 is provided with a large number of vacuum suction holes so as to open on the mold surface forming the cavity 13. That is, this vacuum suction hole performs water squeezing and deaeration in the molding raw material during the dehydration press molding, and after the formation, when the molded uncured cement-based press molded body is conveyed to the next step. ,
It also has a role of adsorbing and holding on the die surface of the upper die 12.

First, as shown in FIG. 1A, the forming raw material 2 is supplied onto the mold surface of the lower mold 11 in the open mold state. Next, as shown in FIG. 1B, the dewatering press mold 1 is closed,
Press molding is performed while dehydrating the molding raw material 2 to mold a cement-based press molded body. At this time, water is sucked from the vacuum suction hole to squeeze and deaerate the molding raw material 2. Next, as shown in FIG. 1C, the molding die 1 is opened while continuing the suction from the vacuum suction hole. At this time, the uncured cement-based press-molded body 3 molded into the shape of the cavity 13 of the press-molding die 1 is in a state of being adsorbed and held on the mold surface of the upper mold 12.

As shown in FIG. 1D, a conveyor belt 4 which continuously advances is provided on the side of the dewatering press mold 1. On the conveyor belt 4, a large number of receiving molds 5 are placed at regular intervals and are continuously fed. The receiving mold 5 is provided with a mold surface 51 corresponding to the outer surface shape of the roof tile to be molded.

The mold surface 51 of the receiving mold 5 may be provided with an uneven surface to evenly disperse the crushed stones or the sand 6 so that the crushed stones or the sand 6 are located on the convex portions on the upper surface of the roof tile product.

Crushed stones or sand 6 are sprinkled on the mold surface 51 of the receiving mold 5 until the conveyor belt 4 reaches the side of the dewatering press molding mold 1. Then, the uncured cement-based press-molded body 3 that is adsorbed and held by the upper die 12 and conveyed is placed on the die surface 51 of the receiving die 5 by releasing the adsorbed state from the vacuum suction hole. Placed.

At this time, the crushed stone or sand 6 was partly digged into the surface layer of the cement-based press-molded body 3 due to the gravity of the uncured cement-based press-molded body 3, and the rest was exposed. It becomes a state. The surface of the cement-based press molded body 3 is in a state of being lifted from the mold surface 51 of the receiving mold 5 by the exposed amount of crushed stone or sand 6.

Next, as shown in FIG. 1 (e), in this state, it is conveyed from the conveyor belt 4 to the curing cabinet together with the receiving mold 5, and the curing curing is performed in the curing cabinet under appropriate curing conditions. . When the cement-based press-molded body 3 is completely hardened, it is taken out from the curing cabinet and demolded, and as shown in FIG. 1 (f), crushed stone or part of sand 6 bites into the surface layer and the remaining portion is exposed. The cured body 7 thus obtained is obtained.

Finally, as shown in FIG. 1 (g), a cured body 7
By coating the surface of the roof tile, a roof tile fixed so that crushed stone or sand partially intrudes into the surface layer and the rest is exposed though not shown.

[0025]

The roof tile manufacturing method of the present invention is
Crushed stone or sand is sprinkled, the uncured cement-based press-molded product is placed with the upper surface facing downward, and it is allowed to cure and cure as it is. It is possible to manufacture roof tiles with high productivity by the press molding method, which is a simple molding method, and the roof tiles obtained are relatively weighted when the cement-based press molded body is placed on the mold. Crushed stone or sand partially penetrates into the surface layer of the cement-based press-molded product and the rest is exposed, and the crushed stone or sand is fixed in that state, so the surface has excellent slip resistance, and the crushed stone Alternatively, the exposed surface of the cement-based press-molded product floats up without contacting the mold surface of the mold, so that the cement slag adhering to the mold surface does not transfer and the appearance is improved. It is also excellent.

[0026]

EXAMPLES Examples of the present invention will be described below. Example Roof tiles were manufactured according to the process described with reference to FIG. As the molding raw material 2 for cement-based press molding, 100 parts by weight of ordinary Portland cement and 40 parts of sand were used.
A mixture of 50 parts by weight of water and 50 parts by weight of water was used. As the crushed stone or sand 6, sharp-angled sand (No. 3 manufactured by Tokai Kogyo Co., Ltd.) having a diameter of 0.5 to 1 mm is used, and it is 0.3 on the mold receiving surface 51.
Sprayed at a rate of ˜0.6 g / cm ² . Curing is 6
It was carried out by holding in a curing cabinet in an atmosphere of 0 ° C. and 90% RH for 6 hours.

The surface of the cured product after demolding was inspected. The purpose of this surface inspection is that if the cement slag adhering to the receiving mold is transferred to the surface of the cured product, it is not possible to obtain a roof tile with an excellent appearance no matter how much coating is performed on it. As a result, almost no adherence of cement slag was observed on the surface of the cured product, and the defective rate was only 0.1%. This is because the surface of the hardened body is slightly raised without directly contacting the mold receiving surface due to the exposed sharp sand, so that the cement residue remaining on the mold receiving surface is not transferred. This is because. On the surface of the cured body after demolding,
Acrylic emulsion was applied at a rate of 0.03 g / cm ² and dried to obtain a roof tile.

With respect to the obtained roof tiles, various objects shown in Table 1 which are expected to come into contact with the surface after laying the roof are placed on the surface, and the angle at which sliding starts when tilted is measured. The sex was evaluated. The results are shown in Table 1.

The obtained roof tiles are
It was laid so as to have a slope of 5 inches, and when observed for one winter period, it snowed up to a maximum of 80 cm, but almost no snowfall occurred. It was the same as when there was no snowfall.

Comparative Example A cured product was obtained in the same manner as in Example except that crushed stone or sand 6 was not used. About the obtained cured body 7,
Surface inspection was performed. As a result, a large amount of cement dregs and the like adhered to the surface of the cured product, and the defective rate reached 0.5%. The surface roof slipperiness of the obtained roof tile was evaluated in the same manner as in the examples. The results are also shown in Table 1.

[0031]

[Table 1]

As is clear from Table 1, the surfaces of the examples of the present invention are less slippery than those of the comparative examples.

[0033]

EFFECTS OF THE INVENTION Since the method for producing a roof tile according to the present invention is constructed as described above, it is possible to produce a roof tile having excellent surface slip resistance and excellent surface appearance without stains with high productivity. It can be manufactured.

[0034]

[Brief description of drawings]

FIG. 1 is an explanatory view illustrating steps of a method for manufacturing a roof tile of the present invention.

[Explanation of symbols]

 1 Dewatering Press Mold 2 Raw Material for Cement 3 Cement Press Mold 5 Receiving Mold 6 Crushed Stone or Sand 7 Hardened Body 11 Lower Mold 12 Upper Mold 13 Cavity 51 Mold Surface

Claims (1)

[Claims] 1. A crushed stone or sand is sprinkled on the surface of the receiving mold, and the cement-based press-molded product in an uncured state is placed on the surface of the receiving mold with the upper surface facing downward, and is allowed to cure and cure as it is. Roof tile manufacturing method.