JPS58966B2 - Manufacturing method of glass fiber reinforced cement board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing glass fiber-reinforced cement boards, and more specifically, to a method for producing glass fiber-reinforced cement boards with excellent delamination strength. .

Conventionally, as shown in Fig. 1, a glass fiber-reinforced cement board made by paper-making is produced by cutting a glass fiber-containing cement thin film (not shown) onto a paper-making cylinder 2 from a glass fiber-containing cement slurry 1. The glass fiber-mixed cement thin film is transferred onto the papermaking blanket 3 that moves in contact with the papermaking cylinder, and wound onto the making roll 4, and the wound glass fiber-mixed cement laminated thin film is cut from the making roll 4 and flattened. It is manufactured by stretching, pressure forming, and curing.

However, when making the glass fiber-containing cement slurry 1 using the conventional paper-making method described above, unless a considerable amount of asbestos is mixed with the glass fibers in the cement slurry 1, that is, no asbestos or a small amount of asbestos (total solid content) is required. As is well known, when glass fiber-containing cement slurry is mixed (within 7 wt% or less), when it is made into the paper-making cylinder 2, the glass fibers make it extremely difficult to remove water, resulting in excessive water removal. A paper-made cement board obtained by cutting a laminated layer of thin films from the making roll 4, pressure forming it, and curing it has the disadvantage that each laminated thin film lacks moisture, so the adhesion between the layers is low and delamination easily occurs. was there.

The present invention aims to provide a novel method for manufacturing a glass fiber-containing cement board that can solve the problem of delamination described above, in which a water box ( water
box) After replenishing water with the hydration machine,
This method is characterized in that the surface of the cement thin film is roughened with a comb or brush to increase the adhesion between the thin film layers that are laminated.

The water box type hydration machine used in the present invention is as shown in FIGS. 2A and B. Water is supplied to a water tank 6 by a water supply device 5 whose water supply amount can be adjusted, and a predetermined amount of water is supplied from the water tank 6. is allowed to overflow 7, and the overflowed water is absorbed by a cloth-like material 8 or a brush-like material 8 attached to the side surface or the lower end of the side surface of the water tank 6, and then the lower end of the cloth-like material 8 or brush-like material 8, that is, a cement thin film. This device supplies a predetermined amount of water absorbed from the edge 10 that contacts the surface of the cement thin film 9 to the surface of the cement thin film 9.

In the present invention, the comb-like object 11 or brush-like object 12 used to roughen the surface of the cement thin film is as shown in FIGS. 3A and 3B, respectively, and these objects are The surface of the cement thin film can be roughened by reciprocating it in a direction perpendicular to the direction of rotation of the rotating or making roll.

Hereinafter, the present invention will be described in detail based on the drawings.

FIG. 4, FIG. 5, and FIG. 6 are explanatory diagrams for explaining one embodiment of the method of the present invention, respectively, and the method shown in FIG. A glass fiber-mixed cement thin film (not shown) is removed from the glass fiber-mixed cement slurry 1 dispersed in the slurry onto a paper-making cylinder 2, and the removed cement thin film is moved in contact with the paper-making cylinder 2. After being transferred onto the papermaking blanket 3 and supplying moisture to the surface of the transferred thin film using the water box 6, the making roll 4
Although not shown below, the rolled cement laminated thin film is cut off from the making roll, rolled out flat, pressure-formed, and then aged to harden.

The method shown in FIG. 5 is almost the same as the method shown in FIG. 4, but the difference is that in the method shown in FIG. On the other hand, in the method shown in FIG. 5, water is supplied to the thin cement surface rolled up on the making roller 4 by means of a water box 6.

The method shown in FIG. 6 is almost the same as the method shown in FIGS. 4 and 5, but the water supply by the water box 6 is performed by winding the water onto the making roll 4 as in the case of FIG. This is a thin film surface, and after hydration, the hydration surface is roughened by reciprocating the comb 11 in a direction perpendicular to the winding direction.

In this method, since the laminated thickness of the thin film wound on the making roll 4 changes, the comb 1
It is necessary to keep the brush-like material 1 or the brush-like material 12 away from the making roll 4 so that there is no difference in the degree of surface roughening in each thin film layer.

The present invention is as explained in detail above, and is a method of laminating and molding thin films made from cement paper containing glass fibers. However, due to the presence of glass fibers, water is removed excessively and adhesive strength is reduced on the surface of the thin film. The adhesion between each thin film layer is extremely good because the water is replenished or the surface is further roughened after water replenishment.

Therefore, the glass fiber-reinforced cement board produced by the method of the present invention has the excellent advantage of being less prone to delamination, and therefore has excellent bending strength and freeze-thaw resistance.

After 28 days of natural curing, a product produced by the method of the present invention (a product with water replenishment) and a product produced by the conventional method, in which a glass fiber reinforced cement board was manufactured by paper-making a cement slurry containing a solid content having the following composition: The results of the bending strength and delamination strength comparison tests are shown in the table below.

Solid composition: Cement 89wt Wastepaper pulp Swt Stonewall Cotton 5wt% Alkali-resistant glass fiber (6mm) 0.5wt% Alkali-resistant glass fiber (1.3mm) 0.5wt% Comparative test results: First invention of the present invention Method Conventional method (hydration) (no hydration) Bending strength (kg/cm2) 290 24
Separation strength between 5 layers (kg/cm2) 42
25

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram illustrating the conventional manufacturing method of a glass fiber reinforced cement paper board, FIGS. 2A and 2B are explanatory diagrams of a water box type hydration machine used in the present invention, and Figures A and 3B are side views of a comb and a brush used in the present invention, respectively;
FIG. 4, FIG. 5, and FIG. 6 are explanatory diagrams each illustrating an embodiment of the present invention. In the figure, 1 is glass fiber mixed cement slurry, 2
3 is a papermaking cylinder, 3 is a papermaking blanket, 4 is a making roll, 6 is a water box, 8 is cloth, 9 is a glass fiber-mixed cement papermaking thin film, 11 is a comb-like object, and 12 is a brush-like object.

Claims (1)

[Claims] 1. A thin glass fiber-mixed cement film is extracted from the glass fiber-mixed cement slurry onto a papermaking cylinder, and the glass fiber-mixed cement thin film is transferred onto a papermaking blanket that moves in contact with the papermaking cylinder, and then wound around a making roll. In the paper manufacturing process for glass fiber-containing cement boards, which are cut out from a making roll, rolled out flat, pressure-formed, and cured, a water box is placed on the surface of the glass fiber-contained cement thin film wound on the making roll. A method for manufacturing a glass fiber-reinforced cement board, which comprises replenishing water using a type water replenishing machine, and then roughening the water replenishing surface with a comb-like object or a brush-like object.