JPH05147012A - Molding sheet for concrete product - Google Patents

Abstract

PURPOSE:To obtain a concrete product which has an uneven pattern on the surface and is superior in surface hardness, by a method wherein a molding sheet is constituted of a moisture impermeable film having irregular surface and a plurality of internal fine through holes and a water absorbing layer formed on the back. CONSTITUTION:A molding sheet 11 is constituted of a moisture impermeable film 12 comprised of a biaxially oriented high-density polyethylene film where a plurality of fine through holes 13 and an uneven form on the surface are formed respectively and a water absorbing layer 14 comprised of nonwoven fabric formed on the back. A transfer ink layer 15 is arranged on the surface of the moisture impermeable film 12. Then at the time of use of the same, the water absorbing layer 14 is caused to abut against a concrete shuttering 20 and concrete 30 is brought into contact with the top of the transfer ink layer 15. Then in accordance with solidification of the concrete 30, surplus water and bubbles are sucked and removed through the fine through hole 13. Furthermore, a form corresponding to the uneven form of the moisture impermeable film 12 is formed on the surface of the concrete 30 and the transfer ink layer 15 is transferred.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete product forming sheet, and more particularly to a concrete product forming sheet for producing a concrete product having a surface having a predetermined uneven pattern and having a sufficient surface hardness.

[0002]

2. Description of the Related Art Conventionally, in the production of concrete products using formwork, concrete is poured into a wooden formwork,
It was done by removing the formwork after curing for a predetermined period. Further, in the case of forming a predetermined rugged pattern on the surface of a concrete product to give an aesthetic appearance, a mold having an uneven shape formed in advance on the inner surface of the mold has been used.

However, a small residue of concrete adheres to the inner surface of the removed formwork, and when this formwork residue is removed and the formwork is reused, the removed residue traces the surface of the next concrete product. Since it appeared in the shape, it was not possible to reuse the mold used once. This is contrary to the protection and effective use of forest resources that have been screaming in recent years.

In order to solve such a problem, a mold made of styrofoam or urethane foam has been used.

[0005]

However, as with a wooden mold, a mold formed using styrofoam or urethane foam, when used by directly pouring concrete into it, causes bubbles and bubbles in the hardening stage of the concrete. Due to insufficient removal of excess water, there have been problems that the surface of the concrete product is rough and the surface hardness is insufficient.
In addition, when painting on the surface of a concrete product, it is necessary to perform a separate process after removing the form, and there is a problem that the process becomes complicated.

The present invention has been made in view of the above circumstances, and provides a concrete product forming sheet for producing a concrete product having a predetermined uneven pattern on the surface and having a sufficient surface hardness. The purpose is to do.

[0007]

In order to achieve such an object, the present invention provides a moisture-impermeable film having at least a desired uneven shape on the surface and having a plurality of fine through holes, and the moisture-impermeable film. The water absorbing layer is formed on the back surface of the wet film.

[0008]

The concrete poured into the mold in which the water absorbent layer side of the concrete product forming sheet having the above-mentioned structure is placed with the water absorbing layer side as the mold side, the concrete does not have excessive moisture or bubbles during a predetermined curing period. It becomes a concrete product with high surface hardness by being absorbed and removed by the water absorption layer after passing through the fine through holes of the moisture permeable film, and the concrete product has a surface shape corresponding to the uneven shape provided on the surface of the moisture impermeable film. Will be given to.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of the concrete product molding sheet of the present invention. In FIG. 1, a concrete product forming sheet 1 includes a moisture impermeable film 2 having a plurality of fine through holes 3 and an uneven surface, and a water absorbing layer 4 formed on the back surface of the moisture impermeable film 2. And a laminated structure consisting of

As the moisture-impermeable film 2, a polyethylene film, a polypropylene film, vinyl chloride, or any other moldable film can be used. The moisture impermeable film 2 preferably has a thickness of about 50 to 300 μm.
Further, the fine through holes 3 formed in the moisture impermeable film 2
The opening width is preferably about 0.1 to 1 mm, and the opening shape may be any shape such as a circle, an ellipse, and a rectangle.
Such fine through holes 3 can be formed into a predetermined shape by hot needle opening, mechanical opening, laser opening, electric opening, or the like.

Further, the uneven shape formed on the surface of the moisture impermeable film 2 can be usually formed by press molding, vacuum forming, vacuum pressure forming, or the like. Further, the uneven shape can be appropriately selected according to the handle, and usually the depth is 0.
It is 5 to 30 mm.

The water absorbing layer 4 is made of non-woven fabric composed of polyethylene terephthalate (PET), polypropylene, polyethylene, rayon, and other chemical fibers such as heat-sealing fibers, cotton, paper, wood, and other materials capable of absorbing water. To be done. The water absorbing layer 4 preferably has a thickness of about 0.5 to 5 mm. The water absorbing layer 4 can be formed on the back surface of the moisture impermeable film 2 by heat fusion or the like.

As shown in FIG. 2, the concrete product molding sheet of the present invention has a transfer ink layer 5 provided on the surface of the moisture impermeable film 2 of the concrete product molding sheet 1 of FIG. Good. The transfer ink layer 5 can be formed using a usual offset ink, gravure ink, silk ink, paint, and the like. In the illustrated example, the transfer ink layer 5 is formed on the entire surface of the moisture impermeable film 2, but the transfer ink layer 5 may be formed only on a predetermined portion of the surface of the moisture impermeable film 2.

FIG. 3 is a schematic sectional view showing another example of the concrete product forming sheet of the present invention. In FIG.
The concrete product forming sheet 11 is a laminate composed of a moisture impermeable film 12 having a plurality of fine through holes 13 formed on both sides thereof and having an uneven shape, and a water absorbing layer 14 formed on the back surface of the moisture impermeable film 12. Have a structure.

The moisture impermeable film 12 can be formed of the same material as the moisture impermeable film 2 described above. The uneven shape can be formed on both the front and back surfaces of the moisture-impermeable film 12 by press molding, vacuum forming, vacuum air pressure, or the like, and the uneven shape can be appropriately selected according to the handle and is usually deep. Is 0.5 to 30 mm. Also,
The thickness of the moisture impermeable film 12 is preferably about 50 to 300 μm. The opening width and the opening shape of the fine through holes 13 formed in the moisture impermeable film 12 are the same as those of the fine through holes 3 described above.
According to.

The water absorbing layer 14 can be formed of the same material as that of the water absorbing layer 4 described above. Further, the concrete product forming sheet of the present invention is, as shown in FIG. 4, a moisture impermeable film 1 of the concrete product forming sheet 11 of FIG.
The transfer ink layer 15 may be provided on the second surface.

Next, the production of concrete products using the concrete product forming sheet of the present invention will be described with reference to FIG. FIG. 5 shows the inside of the mold 20 as shown in FIG.
It is a figure which shows the state in which the concrete product forming sheet 11 as shown in FIG. At the bottom portion of the mold 20 shown in FIG. 5, the water absorbing layer 14 contacts the mold 20 as shown in FIG. 6, and the poured concrete 30 contacts the transfer ink layer 15. It is in a state. In this state, the concrete 30 is cured by curing for a predetermined period of time. During this period, excess water and air bubbles pass through the fine through holes 13 of the impermeable film 12 and are absorbed and removed by the water absorbing layer 14. Then, as shown in FIG. 7, by removing the formwork 20 from the concrete 30 that has hardened after a predetermined period of time, it has a surface shape corresponding to the uneven shape provided on the surface of the moisture-impermeable film 12, A concrete product on which the ink layer 15 is transferred is obtained. Further, since excess water and air bubbles are effectively removed as described above, the surface of the concrete product does not have defective shapes such as pockmarks, and the surface hardness becomes extremely high. Then, by removing the concrete product forming sheet 11 (the transfer ink layer 15 is transferred to the concrete side and does not exist) from the form 20, the form 20 can be used again for concrete production.

Next, the present invention will be described in more detail with reference to specific examples. First, as a moisture-impermeable film, a polyethylene film having a thickness of 22 μm was formed with corrugated irregularities (depth 5 mm, width 3 mm) as shown in FIG. 4 by hot pressing. Further, a through hole having a diameter of about 800 μm was formed in this polyethylene film. This through hole is formed by pressing a hot needle, and the formation density is about 5 pieces /
It was cm ² .

Next, a transfer ink layer was formed on the surface of the polyethylene film by silk printing. Also,
A non-woven fabric having a thickness of 1 mm was adhered to the back surface of the polyethylene film by heat fusion to prepare a concrete product molding sheet of the present invention.

Next, the above concrete product molding sheet was placed inside a wooden mold so that the non-woven fabric side abuts against the mold. Then, concrete having the following mixing ratio was poured into the mold, and cured at room temperature for 1 day to cure the concrete. (Mixing ratio of concrete) -Cement ... 50 parts by weight-Sand ... 100 parts by weight-Water ... 28 parts by weight After hardening, the form was removed to obtain a concrete product. The surface shape of this concrete product was a polyethylene film surface. The shape corresponds to the provided uneven shape, and no defective shape such as pockmark was observed. Further, the formwork from which the concrete product forming sheet was removed was in a state in which it could be used for the same concrete production.

As a comparison, a concrete product was manufactured under the same conditions as above, except that the above polyethylene film was provided with the same corrugated surface and was not provided with through holes and non-woven fabric as a concrete product molding sheet. In this case, the surface hardness of the obtained concrete product was weak, and the surface condition was unfavorable because fluttering was observed.

[0022]

As described in detail above, according to the present invention, excess water and air bubbles are absorbed and removed by the water-absorbing layer through the fine through-holes of the impermeable film in the hardening stage of concrete. A concrete product that has a predetermined uneven pattern on the surface and has a sufficient surface hardness can be easily manufactured, the formwork can be reused, and it can be transferred to the surface of the impermeable film. By providing the ink layer, the surface of the concrete product can be painted at the same time when the concrete product is molded.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a concrete product molding sheet of the present invention.

FIG. 2 is a schematic cross-sectional view showing an example in which a transfer ink layer is provided on the concrete product molding sheet shown in FIG.

FIG. 3 is a schematic cross-sectional view showing another example of the concrete product molding sheet of the present invention.

FIG. 4 is a schematic cross-sectional view showing an example in which a transfer ink layer is provided on the concrete product molding sheet shown in FIG.

FIG. 5 is a view showing a state in which the concrete product molding sheet of the present invention is placed inside a mold.

FIG. 6 is a partially enlarged view of a bottom portion of the mold shown in FIG.

FIG. 7 is a view showing a state in which the form and the concrete product are separated from each other in FIG.

[Explanation of symbols]

 1, 11 ... Sheet for molding concrete products 2, 12 ... Impermeable film 3, 13 ... Micro through holes 4, 14 ... Water absorbing layer 5, 15 ... Transfer ink layer 20 ... Formwork 30 ... Concrete

Claims (4)

[Claims] 1. A moisture-impermeable film having a desired uneven shape on at least the surface thereof and having a plurality of fine through holes, and a water-absorbing layer formed on the back surface of the moisture-impermeable film. A sheet for forming concrete products. 2. The moisture impermeable film is a biaxially stretched high density polyethylene film.
A sheet for forming a concrete product as described above. 3. The concrete product molding sheet according to claim 1, wherein the water absorbing layer is made of a non-woven fabric. 4. The concrete product molding sheet according to claim 1, further comprising a transfer ink layer on at least a part of a front surface of the moisture-impermeable film.