JPH06263504A - Inorganic forming - Google Patents

Abstract

PURPOSE:To improve the strength of an inorganic forming by blending the inorganic forming with linen fiber. CONSTITUTION:A silicic acid raw material, a calcareous raw material, 2-10wt.% linen fiber having <=500cc freeness (JIS-P-8121, Canada type test method) are dispersed into water of 2-6 times based on total solid content and the dispersion is subjected to dehydration forming by press to afford an inorganic forming. This forming is hardened under saturated steam pressure at 140-220 deg.C and then dried.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inorganic molded product such as a cement molded product or a calcium silicate molded product.

[0002]

2. Description of the Related Art As a technique for producing an inorganic molded body such as a cement molded body, raw materials are mixed in an amount of water suitable for each manufacturing method. For example, in the papermaking method, cement and, if necessary, aggregate, admixture, and wood pulp are added in an amount of 2 to 10% by weight and mixed to adjust the solid content concentration to about 2 to 15%. Take the slurry with
Cement was hardened by steam curing or natural curing of the molded body taken out to obtain a cement molded body. On this occasion,
Wood pulp is beaten to improve paper-making and reinforcing properties, and the freeness is 300c according to Canadian type test method (JIS R8121).
It was less than c. However, the wood pulp has a poor reinforcing effect, and the cement compact containing the wood pulp has a problem of insufficient strength.

In the case of a calcium silicate compact, similarly, a siliceous raw material, a calcareous raw material, and if necessary, an aggregate, an admixture and a wood pulp are added in an amount of 2 to 10% by weight, and a solid content of 2 to 15 is added.
%, And the slurry was taken out with a round-amid type paper making machine, and the formed body was aged at 140 to 220 ° C. under saturated steam by an autoclave to obtain a calcium silicate formed body. However, the calcium silicate compact containing wood pulp has a problem of insufficient strength.

Therefore, an object of the present invention is to provide an inorganic molded body which solves the problems such as insufficient strength associated with the inorganic molded bodies such as cement molded bodies and calcium silicate molded bodies using conventional wood pulp. To do.

[0005]

That is, the inorganic molded body of the present invention is characterized by adding and blending 2 to 10% by weight of hemp fiber in terms of inner ratio.

A feature of the present invention is that hemp fibers that have been subjected to a high degree of beating treatment are blended in an inorganic molded body such as a cement molded body or a calcium silicate molded body. For the beating treatment of hemp fiber, the equipment conventionally used for beating wood pulp such as beater or disc refiner can be used as it is.
Reduce to 500 cc or less with IS R8121). In addition, hemp fiber usually has a fiber length of 200 to 250 mm, but it is 5 mm in advance.
It is suitable for beating if it is cut to some extent.

When a cement molded product containing, for example, hemp fibers as an inorganic molded product is manufactured, the conventional manufacturing method can be applied as it is. The raw materials are mixed in an amount of water suitable for each production method. For example, in the papermaking method, 2 to 10% by weight of hemp fiber having a water content of 500 cc or less is added to a slurry in which cement and an aggregate, an admixture, etc. are added, if necessary, and a solid content concentration is 2 to 15%.
%, And the slurry is drawn out by a round-amid paper making machine according to a conventional method, and the formed molded product can be hardened with cement by steam curing or natural curing to obtain a hemp fiber-containing cement molded product. .

In this case, if the water content of the hemp fibers exceeds 500 cc, poor dispersion will occur and the effect of improving the strength will not be recognized. Further, even if the amount of hemp fiber added is less than 2% by weight, the effect of improving the strength is not recognized. Further, when the amount of hemp fiber added exceeds 10% by weight, poor dispersion is apt to occur and the strength developing effect is impaired.

Also in the case of a calcium silicate molded product containing hemp fibers, it can be molded by a conventional method. For example, in the case of press molding, 2-10 wt% of siliceous raw material and calcareous raw material, and 2-10 wt% of hemp fibers having a water content of 500 cc or less are dispersed in water, and after mixing, press dehydration molding is performed. The amount of water at this time is preferably 2 to 6 times the total solid content. The molded body is aged by an autoclave under saturated steam pressure at 140 to 220 ° C., and then dried. Silica powder, diatomaceous earth, silica fume and the like are used as the siliceous raw material, and quick lime, slaked lime, cement and the like are commonly used as the calcareous raw material.

Inorganic aggregates, admixtures and the like can be added as required. If you need lighter weight,
Amorphous silica such as diatomaceous earth is selected as the silicic acid raw material, and the raw material slurry is heated at 90 ° C. or higher under atmospheric pressure for 1 to 2 hours.

At this time, if the water content of the hemp fiber is 500 cc or more, poor dispersion occurs, and the effect of improving strength cannot be recognized. Further, even if the amount of hemp fiber added is less than 2% by weight, the effect of improving strength is not recognized. Furthermore, the addition amount of hemp fiber is 10
When the content is more than weight%, poor dispersion is likely to occur and the effect of developing strength is impaired.

[0012]

[Function] Hemp fiber is the same cellulose fiber as conventionally used wood pulp, but it has high elasticity and high tensile strength because cellulose has higher crystallinity than wood pulp, and is a promising material as a reinforcing fiber. . However, dispersion in the slurry was difficult. By beating the hemp fibers, the dispersibility is improved, and in the beating process, the hemp fibers are fibrillated and the surface area is increased, so that they exhibit excellent properties as reinforcing fibers.

[0013]

【Example】

Examples 1 to 3 Raw materials were weighed at the blending ratios shown in Table 1, poured into water 5 times the solid content, stirred, mixed to form a slurry, and then poured into a mold, and 140 kg / cm ² Dehydration molding was performed under the pressing pressure of. The obtained molded product was steam-cured at 60 ° C. for 8 hours, then dried in a dryer at 100 ° C. until a constant weight was obtained, and the bending strength was measured. Also, after steam curing, the molded body was immersed in water for 24 hours to reach a saturated state, and then the bending strength was measured. The obtained results are also shown in Table 1.

Comparative Examples 1-3 As reinforcing fibers, 5% by weight of hemp fibers having a freeness of 700 cc, 1.5% by weight of hemp fibers having a freeness of 100 cc, and a freeness of 200 c
5% by weight of wood pulp of c.
A fiber-containing cement molded product was obtained by the same method as described above. Table 1 also shows various characteristics of the obtained molded body.

[0015]

[Table 1]

Examples 4 to 5 The raw materials were weighed at the blending ratios shown in Table 2, 4 times the amount of water relative to the solid content was added, and the mixture was stirred and mixed to form a slurry,
It was poured into a mold and subjected to dehydration molding with a pressing pressure of 15 kg / cm ² . The obtained molded body is autoclaved 1
It was cured for 6 hours under a saturated steam pressure of 80 ° C. Then 10
After being dried in a dryer at 0 ° C. to a constant weight, the bending strength was measured. The obtained results are also shown in Table 2.

Comparative Examples 4 to 5 12% by weight of hemp fibers having a freeness of 200 cc as reinforcing fibers,
5% by weight of wood pulp having a freeness of 200 cc was mixed, and hemp fiber-containing calcium silicate compacts were obtained in the same manner as in Examples 4 to 5.

[0018]

[Table 2]

Examples 6 to 7 The raw materials were mixed in the blending ratio shown in Table 3 to obtain a solid content of 7
%, The slurry was made using a round-amid papermaking machine, dehydrated at a pressing pressure of 100 kg / cm ² , and then formed into a molded product having a thickness of 6 mm. The obtained molded body was naturally cured for 2 weeks, left indoors for 2 more weeks, and the bending strength was measured in an air-dried state. The results obtained are also shown in Table 3.

Comparative Example 6 5% by weight of wood pulp having a freeness of 100 cc as a reinforcing fiber
Then, a cement molded product was obtained in the same manner as in Examples 6 to 7 below. Table 3 also shows various properties of the obtained cement molded product.

[0021]

[Table 3]

[0022]

EFFECTS OF THE INVENTION According to the present invention, since hemp fibers are used in place of conventional wood pulp in an inorganic molded article such as a cement molded article or a calcium silicate molded article, the strength is superior to that of the conventional inorganic molded article. Can be obtained.

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location (C04B 28/18 16:02 Z 2102-4G 20:02) A 2102-4G

Claims (3)

[Claims] 1. In an inorganic molded product, 2 to 10 in terms of inner ratio
An inorganic molded article characterized by adding and blending wt% of hemp fiber. 2. The inorganic molded body according to claim 1, which is a cement molded body or a calcium silicate molded body. 3. The inorganic molded article according to claim 1, wherein the water content of the hemp fiber is 500 cc or less according to JIS P8121 Canadian type test method.