JPH0225768B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to the manufacture of concrete plates, concrete walls, etc., in which various decorative patterns such as uneven patterns are applied to the surface of the concrete material that is placed in contact with the surface of the concrete material. The present invention relates to a method for manufacturing a decorative formwork for forming a concrete plate that imparts a pattern.

[Prior art] Conventionally, the above-mentioned decorative formwork for forming concrete plates (hereinafter referred to as decorative formwork) has an integral skin layer on the surface layer made of, for example, foam-curable urethane resin, and the surface is coated with an integral skin layer. BACKGROUND ART It is known that an elastic board with a decorative pattern such as a concave-convex pattern is integrated onto plywood, and is used as a panel together with other framing materials when constructing concrete walls of buildings.

A mold as shown in FIGS. 5 and 6 is used to manufacture such a decorative mold. That is, the mold 1 includes an iron rectangular plate-shaped upper mold 2 provided with a large number of holes 2a in the thickness direction for air release and overflow of the resin composition, and a longitudinal section surrounded by side walls 3a on all sides. It is composed of a lower mold 3 made of aluminum and having a planar shape and whose inner bottom surface is a surface for transferring a decorative pattern such as an uneven pattern.For example, the decorative mold is manufactured as follows.

First, a predetermined amount of uncured liquid resin composition is poured into the inside of the lower mold 3, then a plywood is placed on the surface of the liquid resin composition, and the upper mold 2 is placed on the upper end of the lower mold 3. After the upper mold 2 and lower mold 3 are crimped together to foam and harden the liquid resin composition, the upper and lower molds 2 and 3 are disassembled to form the desired decorative formwork. Take out. Note that the holes 2a provided in the upper die 2 are in the plywood.
A through hole for the same purpose is provided in the thickness direction at a position corresponding to the above.

[Problems to be solved by the invention] However, according to the above conventional manufacturing method,
Not only does it take a lot of effort to provide a large number of holes 2a in the upper mold 2, but also burrs caused by overflow of the resin composition adhere to the many holes 2a, which causes a large problem in disassembling the mold when removing the decorative form after molding. There were problems in that manufacturing efficiency was poor, as it required a lot of force, took time to disassemble, and took time to remove burrs.

The present invention was invented based on the above circumstances, and an object of the present invention is to provide a method for manufacturing a decorative formwork that solves the above-mentioned conventional problems and has excellent manufacturing efficiency.

[Solution]

In order to achieve the above object, the present invention does not provide holes for air venting and resin overflow in the upper mold as in the past, but uses plywood with through holes in the thickness direction and a decorative formwork. While using plywood having a groove that communicates with the through hole and opens at the edge on the surface that will become the back surface, as a lower mold, a plywood that communicates with the groove provided in the plywood on the upper surface of the side wall and inside the side wall. This method is characterized in that the decorative mold is manufactured using a lower mold having a groove that communicates between the decorative mold and the outside.

The upper and lower molds in the present invention are both made of rigid materials such as metal and resin.

Further, the position, number, and size of the through-holes provided in the plywood, and the direction, number, size, cross-sectional shape, etc. of the grooves are appropriately determined by the decorative pattern provided on the surface of the elastic plate that is integrated with the through-holes.

On the other hand, the position, direction, number, size, cross-sectional shape, etc. of the grooves provided on the upper surface of the side wall of the lower mold are appropriately determined in accordance with the grooves provided in the plywood.

Note that the grooves provided in the plywood are formed in a tapered shape so that the groove width becomes smaller toward the open end, and correspondingly, the grooves provided in the lower mold also become narrower toward the inner open end of the side wall. It is preferable to form the burr in a tapered shape as shown in FIG. 1 because the burr can be easily removed by hand.

Furthermore, the bottom surface of the upper mold, the inner surface of the lower mold, and the grooves are coated with a mold release coating, or a mold release agent is applied during molding.

[Effect]

According to the manufacturing method of the present invention configured as above,
Air trapped when the plywood is placed on the surface of the liquid resin composition cast inside the lower mold, gas generated by subsequent foaming of the resin composition, and overflow of the resin composition. is emitted to the outside through the through holes and grooves provided in the plywood, and further through the grooves provided on the upper surface of the side wall of the lower mold. Therefore,
On the plywood surface that is the back surface of the decorative formwork, burrs are formed due to overflow of the resin composition and are integrated with the elastic plate formed on the opposite surface. Therefore, actual burrs are formed only in the grooves provided in the lower mold, and when the mold is disassembled, the upper mold is easily removed because no burrs are stuck to the upper mold, and the burrs are removed. It can also be easily removed by cutting or the like after demolding the decorative form. In particular, the groove provided in the plywood is formed in a tapered shape so that the groove width becomes smaller toward the open end,
In addition, if the groove provided in the lower mold is also tapered so that the groove width becomes smaller toward the inner open end of the side wall so that both grooves are in communication, it is necessary to remove the makeup before disassembling the mold. After removing the formwork, it can be easily removed by pulling it by hand.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to reliably remove the air trapped during molding and the gas generated by foaming of the resin composition, etc., and also to actively remove most of the overflow of the resin composition from the product. The manufacturing efficiency is very high because the burrs that must be integrated as a part of the product and actually removed are as small as possible and can be easily removed.

〔Example〕

Figures 1 and 2 show an example of a mold 10 used in the manufacturing method of the present invention, and have a width of 1120 mm and a length of 1860 mm.
× Width 960 × Length: 50 mm thick rectangular plate-shaped iron upper mold 20, vertical cross-sectional shape surrounded by side walls 32 on all sides, and inner bottom surface with uneven pattern transfer surface.
It consists of an aluminum lower mold 30 with a size of 1860 x 100 mm in height and a side wall thickness of 30 mm. A plurality of grooves 34 having a rectangular cross section and a width of 3 mm are provided at predetermined locations on the upper surface of the side wall 32 of the lower mold 30, and the grooves 34 have a rectangular cross section and communicate between the inside and the outside.

On the other hand, FIGS. 3 to 4 show an example of the plywood 40 used in the manufacturing method of the present invention, and the size is
900 x length 1800 x thickness 12 mm, a plurality of through holes 42 with a diameter of 10 mmφ are provided in the thickness direction, and a groove 44 with a rectangular cross section and a width of 3 mm opens at the edge, connecting these through holes 42. There are multiple articles.

Prepare these molds 10 and plywood 40,
First, a predetermined amount of a liquid urethane resin composition containing a foaming agent and a curing agent was cast inside the lower mold 30 . Next, the plywood 40 is placed on the surface of the liquid so that the grooves 44 are located above, and the upper mold 2 is placed on the surface of the liquid material.
0 was placed on the upper end of the lower mold 30. On the other hand, the urethane resin composition gradually started foaming about 60 to 80 seconds after casting, and curing was completed in 2 to 3 minutes thereafter. During this time, internal foaming pressure is generated, and the plywood 40 and the lower mold 30
The surface layer constituting the elastic plate in contact with the inner surface became an integral skin layer. Furthermore, most of the overflow of the urethane resin composition is filled in the through holes 42 and grooves 44 provided in the plywood 40, and the burrs that must actually be removed are in the grooves 44 provided in the lower mold 30.
Formed into 4 parts. Thereafter, after the resin composition was cured and aged, it was demolded and the decorative mold was taken out. that time,
Since no burrs were attached to the upper mold 20, disassembly of the mold 10 was extremely easy. Finally, the burrs were cut and removed from the decorative formwork taken out using scissors.

[Brief explanation of drawings]

1 and 2 show an embodiment of the mold used in the present invention, in which FIG. 1 is a plan view, FIG. 2 is a sectional view taken along line A-A in FIG. 1, and FIGS. Fig. 4 shows an embodiment of plywood used in the present invention, Fig. 3 is a plan view, Fig. 4 is a sectional view taken along line BB in Fig. 3, and Figs. 5 and 6 are conventional plywood. This shows an example of the mold used in the manufacturing method of
The figure is a plan view, and FIG. 6 is a sectional view taken along line CC in FIG. 5. 10... Molding die, 20... Upper die, 30... Lower die, 32
...Side wall, 34...Groove, 40...Plywood, 42...Through hole,
44...Groove.

Claims (1)

[Scope of Claims] 1. A method for manufacturing a decorative formwork for forming a concrete plate, which is formed by integrating an elastic board with a decorative pattern on the surface onto plywood, the formwork having a vertical cross-sectional shape surrounded by side walls on all four sides. and pouring a predetermined amount of a liquid resin composition into the inside of the lower mold, which has an inner bottom surface as a decorative pattern transfer surface and a groove on the upper surface of the side wall that communicates the inside and outside of the side wall,
Next, a large number of through holes are formed in the thickness direction above the liquid surface of the liquid resin composition, and the through holes are communicated with the back side of the decorative form and are opened at the edges, and the lower A piece of plywood having a groove that can communicate with the groove provided in the mold is placed on the upper end of the lower mold, and the plywood is shaped like a rectangular flat plate and the bottom surface of the edge is flush with the upper surface of the side wall of the lower mold. Place the upper mold to be crowned,
After that, the upper and lower molds are crimped together, the liquid resin composition is cured, and then the upper and lower molds are disassembled to take out the decorative formwork. Method.