JPS5888156A - Manufacture of fiber reinforced lightweight cement formed body - 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 The present invention relates to a fiber-reinforced lightweight cement 1 to a method for producing a molded article.

Conventionally, the manufacturing method of fine air-filled cement bodies reinforced with various fibers such as inorganic fibers involves mixing fine air bubbles in cement slurry, and creating a mixing area on a belt conveyor where this air-filled cement slurry and short glass fibers are mixed. Spray and disperse each one on a conveyor belt! - A method of forming continuous pine I and curing and solidifying it (Japanese Patent Application Laid-Open No. 49-13
(see No. 0421), or by adding aluminum powder or a foaming agent to cement slurry to make foamed cement slurry, then adding alkali-resistant glass fiber to this foamed cement slurry to make a foaming premix, and drying the foaming premix. After using the molding raw material as a molding raw material, a molded body is prepared by press molding or []-ru molding, and the molded body is cured and solidified (see JP-A-52-81324). Using a foaming agent mixed with a cationic bamboo W surfactant, a cement slurry mixed with alkali-resistant glass fiber is foamed to produce a molded body.3S! i method (see JP-A-54-1323)
etc. are known.

However, the molded bodies produced by these conventional methods have a low residual rate of air bubbles, and have poor properties when it comes to sawdust and nailing. It also has various drawbacks such as poor air bubble association, poor bubble uniformity (inconsistency in strength of the molded product, and poor surface properties).

The present invention improves the drawbacks of the prior art and makes the cementitious slurry into an aerated slurry, and mixes reinforcing fibers into the aerated slurry to contain reinforcing m1Ii. This foamed slurry containing reinforcing fibers was dehydrated by suction using a filter cloth J. ! This is a method for manufacturing a fiber-reinforced lightweight cement molded body, which is characterized in that the molded body is produced by biosolidification.

That is, in the present invention, short fibers →
By adding air bubbles and reinforcing fibers in this order, it is possible to prevent R1 of fiber balls that are formed when fibers are entangled with each other, to evenly disperse the fibers, and to obtain a molded product with a high air content.

Then, the reinforcing fiber-containing foam slurry uniformly mixed with fine air bubbles is supplied onto the filter cloth, and the excess water is immediately dehydrated by suction to eliminate the fluidity of the reinforcing 11M-containing foam slurry.
By maintaining the desired shape of the molded body, the air bubbles are uniformly fixed in the molded body, and it is possible to prevent the air bubbles from joining together and from becoming coarse. In addition, by mixing short fibers in the slurry in advance, during suction dehydration, the cushioning effect of the short fibers prevents unevenness on the surface of the molded product, and furthermore, during handling such as transportation after demolding the molded product. It can prevent micro-cracks that tend to occur.

In this way, in the present invention, the air bubbles, short fibers, and reinforcing fibers are uniformly dispersed in the molded product, so the molded product has no variation in strength and can be cut cleanly with a saw. It becomes possible to use a nail driving spatula.

In addition, in the present invention, since the uncured molded body is dehydrated, it has good shape retention, and if the molded body is plate-shaped, it is possible to demold and store the uncured molded body separately. This also has the effect that they do not stick to each other even during curing and hardening by stacking.

As the cementitious material used in the present invention, portland cement, alumina cement, silica cement, fly ash cement, slag cement, granulated slag, etc. can be used. Mortar materials containing perlite, shirasu balloons, calcium carbonate, gypsum, etc. can also be used as the cementitious material of the present invention depending on the purpose of the molded product.

As the short fiber material, fibers such as bulb fiber, slag fiber, rock wool, glass fiber, etc. can be used, and the length of the short fiber is 1 to 10 ma+, and the added amount is 1 part by weight per 100 parts by weight of the cementitious material. A preferable range is 10 to 10 parts. If the amount of short fibers added exceeds the above value or the fiber density is increased, the fibers tend to become entangled with each other and form fiber balls during mixing with the cementitious slurry, and the cementitious slurry containing these fiber balls tends to Molding the molded product is undesirable because it adversely affects the physical condition and surface properties of the molded product.

As reinforcing fibers, 1 m of inorganic materials such as alkali-resistant glass fibers, organic synthetic fibers such as polypropylene and polyamide, and vegetable fibers such as hemp can be used, and the tMH length thereof is 10 to 50 Illll11. The preferred range is 1 to 5 parts by weight. If the above-mentioned addition amount and WEAN length of reinforcing fibers are exceeded, there is a tendency to form 7-fiber balls and poor surface formability as in the case of short fibers, and if the addition amount and fiber length are less than the above-mentioned addition amounts, the reinforcing effect will be poor. It doesn't appear.

The reinforcing taN is typically mixed into the air bubble-containing slurry by a spray method, in which both are sprayed with a spray gun to create a mixing area, or by mixing the air bubble-containing slurry with a mixer. An example of this method is to add the reinforcing IIH while sequentially dispersing it from above, but any other method may be used as long as it does not generate fiber balls.

As for the method of mixing air bubbles and the foaming agent used in the present invention, known methods can be adopted.

As a foaming agent, a nonionic surfactant is effective since cement compositions generally have a high pH and a large amount of calcium ions, but in the present invention, pre-manufactured air bubbles are introduced into the cementitious slurry. Therefore, it is possible to use relatively inexpensive anionic surfactants as foaming agents. For example, commercially available anionic surfactants such as notorium dodecyljethoxyethyl sulfate and sodium dodecylbenzsulfonate, which are used when air bubbles are mixed into plasterboard, are used as foaming agents. Any surfactant can be used.

Next, I will explain an example of how to mix air bubbles.
A 1.5 fF (converted)% aqueous solution of a surfactant (product name 11 Tmar 030", manufactured by Kao Atlas Co., Ltd.) and pressurized air were continuously introduced into the inlet tube at the top of the circular solid foamer filled with Raschig ring. and generate fine air bubbles from the take-out tube at the bottom of the foaming lid.

A foamed cementitious slurry can be produced by introducing the air bubbles into the bottom of a mortar mixer equipped with an agitator using a hose and kneading the air bubbles with a cementitious slurry containing short tlAH.

The upper limit of the amount of air bubbles added is 0.4 to 0.5 g per 111 kg of cement material, and above this amount, it is difficult to uniformly disperse the air bubbles into the cement slurry. As a result, the physical properties of the molded article are adversely affected.

In addition, the material of the filter cloth used in the present invention can be woven organic fibers such as polyamide, polyester, polypropylene, hemp, or felt, and paper can also be used if it is disposable only once. It is. The air passing through the filter cloth is 5 to 80CC/Cl12・Se.
C range is preferred, especially 20 to 60 CC/C
11l'-SeO is preferred.

In the present invention, the moisture content of the cement slurry is 50 to 200 parts by weight of water per 1100 parts by weight of the cementitious material F1, but the moisture content of the molded product after suction dehydration is 15 to 200 parts by weight.
30 parts is preferable; if it exceeds this value, the strength of the molded product will be weak, the bubbles will move easily, and the bubbles will often collect and coarsen and escape, and the strength and density of the molded product will be uneven. .

Next, the suction pressure in the present invention is approximately -1 at the start of suction.
Preferably, suction is applied at 0 cmHg and gradually increased to 50 CIIll-10 as excess moisture in the molded body is dehydrated.

The foamed slurry containing reinforcement III is formed by pouring the slurry prepared by the premix method as described above onto a filter cloth of a predetermined shape to a predetermined thickness, and shaping the surface with a roll or trowel to form a filter cloth. Alternatively, instead of the premix method, the slurry containing air bubbles and the reinforcing fibers may be directly sprayed onto the filter cloth F using the above-mentioned spray method to contain the reinforcing fibers to a predetermined thickness. A foamed slurry may be prepared, molded using a roll or the like, and then dehydrated by suction.

Further, the filter cloth is used as an endless belt, and the reinforcing fiber-containing cellular slurry is continuously supplied onto the filter cloth by the two methods described above, and a plurality of forming rollers, forming belts, etc. are placed downstream of the feeding place. A number of suction and dehydration cylinders are placed below the filter cloth, and these equipment continuously performs F.
A band-shaped molded article can also be produced by molding and dewatering the slurry.

Although the embodiments of the present invention are described below in a small scale, the present invention is not limited thereto.

[Example] A cementitious slurry consisting of a cementitious material having the composition shown in Table 1, short fibers, and water was produced using Shishitarumi-1 Sur,
Air bubbles were introduced into this at the bottom of a mortar mixer to produce an aerated cementitious slurry.

Air bubbles are produced using a surfactant (product name: "Tmarl 03").
A 1.5% by weight aqueous solution of 1" (manufactured by Kao Atlas Co., Ltd.) and BN Fr air were continuously introduced into the introduction tube of a cylindrical foamer filled with a Raschig ring (φ), and fine particles were generated from the bottom of the foaming lid. The amount of air bubbles used in the surfactant layer 1 was 0.03 per 100 parts by weight of Portland cement.
Parts by weight.

Next, the cementitious slurry containing air bubbles is sprayed onto the filter fabric soil shown below using a spray gun to make it as smooth as possible, and at the same time, reinforcing IIN shown in Table 1 is sprayed onto the filter fabric soil to make the aerated slurry containing fibers reinforced with the filter fabric soil. was manufactured.

The filter cloth is a nylon fiber woven fabric with ventilation passing through R1!38cc/c
The surface of the suction dewatering device is a perforated iron plate (hole diameter: 4111111, hole spacing: 25n).
+m) is laid on an iron plate.

Reinforcement of Filter Fabric-F After smoothing the surface of the IN-containing foam slurry with a roll, the airflow was dehydrated for 30 seconds at 10c...1 (a), the surface was formed again with a roll, and then the airflow was adjusted to 10c...1 (a). 30cm) (g) and dehydrated for 1 minute to produce a green plate molded body.

Next, the green plate molded body was removed from the filter cloth 1 using a suction dehydrator and cured at room temperature to obtain a sag-containing light cement molded body having a thickness of about 12 g and 1 l.

The physical properties of the obtained lightweight cement molded body were measured and are shown in Table 1. In addition, the air residual rate in Table 1 indicates the amount of air remaining in the cement molded body in the air bubble-containing slurry as a percentage. - Attach a 10 kg weight to
Measurement of the number of seconds required to move the diamond cutter using the force of the smoke and cut the molded object 3001,
The value of nailability was calculated by dropping a weight of 300 g from a height of 30 cra onto a round iron nail placed perpendicular to the surface of the molded body, and then dropping the tip of the round iron nail through the molded body in accordance with JIS 5410 of 1960. The number of falls until it jumps out from 1 ci is measured.

Comparative examples are also listed in the lower row of Table 1-1.

Comparative Example 11, produced under the same conditions as Example except that air bubbles were not mixed into the cementitious slurry; Comparative Example 2
．． Comparative Example 3 is an example in which reinforcing II and short mH are not mixed, respectively, and Comparative Example 4 is an example in which the reinforcing fiber-containing foam slurry of the example is not suction-dehydrated.

As described above, the present invention has a high residual rate of air, has a bending strength that can be used in practical use, can be cut with a saw and nailed well, and can be used for wall boards of various buildings, etc. It can be widely used.

Patent applicant: Central Glass Co., Ltd. Agent Patent Attorney Hidetake Komatsu

Claims (1)

[Claims] Fine air bubbles are mixed into a cementitious slurry mixed with short fibers and stirred to disperse them uniformly, the cementitious slurry is made into an air bubble slurry, and reinforcing fibers are mixed into this slurry containing air bubbles to form reinforcing fibers. A wJ manufacturing method for a II miscellaneous reinforced lightweight cement molded body, which is characterized in that a foamed slurry containing reinforcing fibers is prepared, the foamed slurry containing reinforcing fibers is dehydrated by suction through a filter cloth F, and then cured and solidified to produce a molded body.