JPS6120708A - Manufacture of building board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field 1] The present invention relates to a method of manufacturing a building board such as a roofing material.

[Background Art] Generally, when building boards A made of asbestos cement are used as roofing material A as shown in FIG. This tends to cause strain when walking. For this reason, this part B
It may be possible to cover the reinforcing plate with a reinforcing plate to prevent cracking, but this not only requires special members but also requires time and effort to construct. Therefore, in the past, asbestos-cement slurry was scooped up using a papermaking cylinder, and this asbestos-cement slurry was transferred to a felt conveyor to form a single-layer wet mat.Then, the entire surface of the single-layer wet mat was covered with polypropylene fibers as reinforcing fibers. , building boards were manufactured by spraying reinforcing fiber cement slurry containing polyacrylonitrile fibers, etc., and these building boards were used as roof boards forming a single layer, but since the entire structure was reinforced, Not only is the reinforcing fiber cement slurry wasted, but the adhesion between the fibers and cement in the reinforcing fiber cement slurry is worse than asbestos and cement, and the layer has a lower specific gravity than asbestos cement slurry, resulting in poor interlayer adhesion. It also had problems such as 1 and 11, in which the reinforcing effect was reduced unless the press pressure was increased and sufficient compression was performed.

[Objective of the Invention 1 The present invention has been made in view of the above-mentioned circumstances, and its purpose is to make it possible to reinforce construction boards, focus on reinforcement of missing parts, suppress warping, etc. The object is to also enable reinforcement of the entire construction board.

[Disclosure of the Invention] The method for manufacturing a construction board according to the present invention includes forming an asbestos-cement slurry 2 using a paper-making cylinder 1 and transferring the asbestos-cement slurry 2 to a felt conveyor 3 to form a single-layer wet mat 4. , Next, a reinforcing fiber cement slurry 6 is sprinkled on the parts corresponding to the reinforced parts on the single-layer wet mat 4, - After that, a green sheet 8 is formed by winding it on a making roll 7, and then the green sheet 8 is pressed to dehydrate it. This structure is characterized by curing and then curing, and with this structure, the above object can be achieved.

The present invention will be explained below based on the accompanying drawings.

Reference numeral 1 denotes a papermaking cylinder, which is partially immersed in asbestos-cement slurry 2 in a slurry tank 9 and rotates to form a green board 10 on the outer periphery, and this green board 10 is transferred to a felt conveyor 3 to form a single layer wet. A mat 4 is formed. Asbestos cement slurry 2 contains 7 to 15 parts by weight of asbestos, 5 to 15 parts by weight of filler such as silica fine particles, and paper-making aid 1 such as a valve.
~2 parts by weight, blast furnace cement, Boltland cement,
It is formed by mixing 2.5 to 3.5 times the amount of mixing water to the solid content of 70 to 85 parts by weight of cement such as No. 7 Liash. 7- Sprinkle the reinforcing fiber cement slurry 2 on the portions of the single-layer wet mat 4 on the Eldronveyor 3 that correspond to the reinforced portions, for example, the shaded portions shown in FIG. Reinforcing fiber cement) Slurry 2 is made of polypropylene fibers, polyacrylonitrile fibers, vinylon fibers, carbon MILIA, etc. with a fiber diameter of 1 to 5 d and a fiber length of 3 to 8 m + n.
1 to 5 parts by weight of reinforcing fibers, 4 to 10 parts by weight of asbestos or 30 to 60 parts by weight of crushed asbestos-cement product waste, and 1.5 to 1.5 to 1.5 to 1.5 parts by weight based on the solid content consisting of 180 to 210 parts by weight of cement as described above. It is obtained by blending and mixing 2.2 times the amount of mixed water and other coloring materials such as pigments and carbon paste as needed. This reinforcement w1. ! J1. The amount of cement slurry 2 to be sprayed is 0.45 to 0.8 kg/m2 in terms of solid content. Thereafter, the required layer (4/GW in the illustrated example) is wound onto the making roll 7, and then cut out to form the green sheet 8. Next, the green sheet 8 is placed on a water-draining metal plate or the like and pressed through a water-draining felt to remove water. In this case, as shown in FIG.
As shown in the figure, the press pressure is sufficiently increased, the specific gravity of the part to be reinforced is increased, and the reinforced i-fiber cement is formed.
The adhesion between the reinforcing i-fiber and the filler in step 3 is improved, resulting in thicker interlayer adhesion and curling strength, which significantly improves the reinforcing effect. It is cured and then left in the air for curing to obtain a building board A. This building board A is cut into a desired size and shape to be used as a roofing material B or the like.

Next, the present invention will be explained in detail based on examples.

Note that the present invention is not limited to the following examples.

In the following, % indicates wt%.

(Example 1) Asbestos (5 and 6 class mix) 13%, B class blast furnace cement 7
6%, No. 8 silica, 10%, and pulp (waste newspaper) 1%, the reinforcing part of the single layer wet mat is made of 1.5% vinylon of wl, a diameter 2d, fiber #I length 6I,
Asbestos (mixture of classes 5 and 6) 7%, class 8 blast furnace cement) 9
A reinforced i, ta cement slurry with a slurry concentration of 32% and a solid content of 0.6 kg/+n2 was applied at 1.5%. Next, this single-layer wet mat was wound up on a making roll and cut out to form a green sheet consisting of four layers. After that, it was pressed at a pressure of 80 kg/cm2 for a holding time of 1.5 seconds, and then cured for 10 minutes at 60°C and 90% RH.
It was cured under moist heat for a period of time and then left in the air for 7 days for secondary curing to obtain a construction board with a thickness of 5.65 mm. The bulk specific gravity of the reinforcing fiber cement layer was 1.70. 500m of this thing
The m-span bending fracture load and warpage were measured. The results are shown in Table 1.

(Example 2) Add 1.5 parts vinylon to reinforcing fiber cement slurry.
A building board with a thickness of 5.65 mm was obtained in the same manner as in Example 1 except that the cement was 92%. The bulk specific gravity of the reinforcing fiber cement layer was 1.72. 500 of this stuff
+am span bending fracture load and warpage tests were conducted.

The results are shown in Table 1.

(Comparative Example) The same procedure as in Example 2 was carried out except that the reinforcing N & fiber cement slurry was spread over the entire surface of the single-layer sea urchin, sea urchin, and tomato.
A construction board of 65m+n was obtained. The bulk specific gravity of the reinforced WLm cement layer was 1.67. 500τn of this [
N-span bending fracture load and warpage tests were conducted. Results first
Shown in the table.

(Comparative Example 2) The same procedure as in Example 2 was carried out except that reinforcing fiber cement free was spread over the entire surface of the single-layer sea urchin, to a thickness of 5.6 mm.
A construction board of 5+n+n was obtained. The bulk specific gravity of the reinforcing fiber cement layer was 1.70. 500111I of this
Span bending fracture load and warpage tests were conducted. The results are shown in Table 1.

Table 1 Measurement method Bending fracture load...5=50011 as shown in Figure 6
Sample 11 was placed between 1111 spans so that the papermaking direction was in the direction of the arrow, and a load was applied from above to measure the load at which it would break.

Warpage: As shown in Figure 7, a 22kg asphalt roofing block was laid on a concrete panel, and nine roofing material samples 11, which were made from construction boards cut to a specified size, were nailed on top of it. After applying an acrylic styrene emulsion paint with a film thickness of 20 to 40 μm, heat it for 3 hours with an infrared lamp 12 from a height of 50 cm + n at a surface temperature of 70° C. to observe warpage and reaction.

From Table 1, it can be seen that the density of the reinforcing fiber cement layer can be made higher in the examples of the present invention than in the comparative examples;
It can be seen that the reduction in specific gravity due to the addition of reinforcing M and navy blue can be prevented, the bending fracture strength is high, and the warpage is also small, so the reinforcing effect is large.

[Effects of the Invention] In the present invention, an asbestos-cement slurry is drawn up using a paper-making cylinder, and this asbestos-cement slurry is transferred to a felt conveyor to form a single-layer wet mat, and then a single-layer wet mat is formed. Since the reinforcement IA cement slurry is sprinkled on the parts corresponding to the reinforced parts,
Not only does it eliminate unnecessary spraying of reinforcing M&fiber cement in unnecessary areas, but it also allows more sufficient pressing pressure to be applied to the reinforcing fiber cement cement layer when pressing and dewatering the green sheet. This improves the adhesion between the reinforcing fibers, cement, and filler, increasing the reinforcing effect, and increasing the strength of the architectural board as a whole, such as reducing warping.

[Brief explanation of drawings]

FIG. 1 is a partially omitted schematic diagram showing an apparatus for carrying out an embodiment of the present invention, FIG. 2 is a plan view showing the state of dispersion of reinforcing i-fiber cement slurry in the above, and FIGS. 3 and 4. are the XX cross-sectional view and the Y-Y cross-sectional view of FIG. 2, FIG. 5 is a cross-sectional view showing the state of the green sheet after pressing in the same as above, and FIG. 6 is a plan view showing the method for measuring bending fracture strength.
7(a) and 7(b) are a plan view and a side view showing a method for measuring warpage, and FIG. 8 is a plan view showing a state in which construction boards are used as roofing material. 3 is an asbestos cement slurry, 3 is a felt conveyor, 4 is a single layer wet mat, 6 is a reinforced fiber cement slurry, 7 is a making roll, and 8 is a green sheet. Agent Patent Attorney Ishi 1) ShichiL Ai Figure 4 Figure 5 Figure 6 Figure 117 Figure 8vA Procedural amendment (spontaneous) August 20, 1981 Patent Application No. '+42903 No. 2, Invention Name: Manufacturing method for construction boards 3, Relationship with the case of the person making the amendment Patent applicant address: 1048 Oaza Kadoma, Kadoma City, Osaka Name (583) Matsushita Electric Works Co., Ltd. Representative Iku Kobayashi 4, Agent Postal code 530 5, "Drain plate" on page 5 of the statement with the date of the amendment order @ lines 8 to 9
has been corrected to "water draining iron plate". Procedural amendment (method) % formula % 1. Indication of the case Patent Application No. 142903 of 1982 2. Name of the invention Method for manufacturing architectural boards 3. Person making the amendment Relationship with the case Patent applicant address Osaka Prefecture 1048 Ou Kadoma, Kadoma City Name (
583) Matsushita Electric Works Co., Ltd. Representative Iku Kobayashi 4, Agent postal code 530 5, Date of amendment order October 9, 1980 6, Specification subject to amendment

Claims (1)

[Claims] (1) Asbestos-cement slurry is drawn up using a papermaking cylinder, this asbestos-cement slurry is transferred to a felt conveyor to form a single-layer wet mat, and then reinforcing fiber cement is applied to the parts corresponding to the reinforced parts on the single-layer wet mat. A method for producing a construction board, which comprises: spreading a slurry, then winding it up on a making roll to form a green sheet, then pressing and dewatering the green sheet, and then curing it.